CCNA Todd Lammle Ch 6 - 9
Textbook Notes by Michael Banks 2021-2023
(The jumping around between colors: a memory-hack i was trying for the exam!)
Chapter 6 Exam Essentials Cisco's IOS
1. Describe the responsibilities of the IOS
network protocols and supporting functions
connecting traffic between devices
adding security to control access
providing scalability and reliablity
2. What are the options to connect to a Cisco device for management purposes?
console port
auxillary port
telnet
3. Understand the boot sequence of a router
POST, load IOS from flash memory, find the startup-config in NVRAM.
if no startup-config is present in NVRAM, the device enters setup mode
4. Describe the use of setup mode
starts automatically if no startup-config found in NVRAM.
Can also enter manually by typing setup from privileged mode
5. Differentiate user, privileged, and global configuration modes,
both visually and from a command capabilities perspective
user mode AKA exec mode
routername>
very few available commands by default. Cannot view or change configuration
privilieged mode AKA priviliged exec mode
routername#
allows you to view and change configurations.
global configuration mode
routername(config)#
allows you to view and change GLOBAL configurations. and to reach other prompts (see below)
6. Recognize addiional prompts available in other modes and describe their use
interface mode
routername(config-if)#
change interface settings
subinterface mode
routername(config-subif)#
change subinterface settings (logically divide a single physical interface)
line configuration mode
routername(config-line)#
set passwords and make other changes to various connection methods
line configuration mode
routername(config-router)#
enable and configure routing protocols
7. Access and utilize editing and help features: question mark, command history, caret, hot keys
A question mark at the prompt will show a list of all available commands for that prompt:
Router#
?
Exec commands:
access-enable
create a temporary access-list entry
access-profile
apply user-profile to interface
access-template
create a tempoary access-list entry
archive
manage archive files
auto
execl level automation
bfe
for manual emergency modes setting
calendar
manage the hardware calendar
cd
change current directory
[OUTPUT CUT]
Filter command help by adding letters to the question mark:
Router#
c?
calendar
cd
clear
clock
cns
configure
connect
copy
crypto
ct-isdn
Router#
c
note that the c remains in place; the system assumes you are going to use it
to find the next command in a string, type the first command with a question mark:
Router#
clock ?
read-calendar
read the hardware caleandar into the clock
set
set the date and time
update-calendar
Update the hardware caleander from the clock
Router#
clock set?
hh:mm:ss
Current Time
Router#
clock set 11:15:11 ?
<1-31>
Day of the month
MONTH
Month of the year
Router#
clock set 11:15:11 25 april ?
<1993-2035>
year
Router#
clock set 11:15:11 25 april 2011 ?
<cr>
carriage return is the only remaining option for this command
Notice how the ? is not showing ALL required params; only showing the NEXT required param
ERRORS
Router#
clock set 11:15:11
% incomplete command
not providing all required params
Router#
sh serial 0/0/0
^
Invalid input detected a the '^' marker
not providing all required params
The problem here is that the full command is:
show interface serial 0/0/0
Router#
sh ru
% Ambiguous command: "sh ru"
means there are multiple commands that being with the string youre using.
Use the question mark to find the command you want:
sh ru?
rudpv1
running-conig
there are two commands that start with
show ru
8. Identify the information provided by the show version command
Router>
show version
Cisco IOS Software, C1900 Software (C1900-UNIVERSALK9-M), Version 15.1(4)M4, RELEASE SOFTWARE (fc2)
Technical Support: http://www.cisco.com/techsupport
Copyright (c) 1986-2007 by Cisco Systems, Inc.
Compiled Wed 23-Feb-11 14:19 by pt_team
describes the Cisco IOS running on the router
ROM: System Bootstrap, Version 15.1(4)M4, RELEASE SOFTWARE (fc1)
cisco1941 uptime is 1 minutes, 29 seconds
System returned to ROM by power-on
System image file is "flash0:c1900-universalk9-mz.SPA.151-1.M4.bin"
Last reload type: Normal Reload
describes the ROM used, which is used to boot the router and hold the POST
This product contains cryptographic features and is subject to United
States and local country laws governing import, export, transfer and
use. Delivery of Cisco cryptographic products does not imply
third-party authority to import, export, distribute or use encryption.
Importers, exporters, distributors and users are responsible for
compliance with U.S. and local country laws. By using this product you
agree to comply with applicable laws and regulations. If you are unable
to comply with U.S. and local laws, return this product immediately.
A summary of U.S. laws governing Cisco cryptographic products may be found at:
http://www.cisco.com/wwl/export/crypto/tool/stqrg.html
If you require further assistance please contact us by sending email to
export@cisco.com.
Cisco CISCO1941/K9 (revision 1.0) with 491520K/32768K bytes of memory.
Processor board ID FTX152400KS
2 Gigabit Ethernet interfaces
DRAM configuration is 64 bits wide with parity disabled.
255K bytes of non-volatile configuration memory.
249856K bytes of ATA System CompactFlash 0 (Read/Write)
License Info:
License UDI:
-------------------------------------------------
Device# PID SN
-------------------------------------------------
*0 CISCO1941/K9 FTX15241343-
Technology Package License Information for Module:'c1900'
----------------------------------------------------------------
Technology Technology-package Technology-package
Current Type Next reboot
-----------------------------------------------------------------
ipbase ipbasek9 Permanent ipbasek9
security None None None
data None None None
Configuration register is 0x2102
9. Set the hostname of a router
Router>
Router>enable
Router#configure terminal
Enter configuration commands, one per line. End with CNTL/Z.
Router(config)#hostname Michael
Michael(config)#
Router>
enable
Router#
configure terminal
Enter configuration commands, one per line. End with CNTL/Z.
Router(config)#
hostname Michael
Michael(config)#
10. Differentiate the enable password and enable secret password
Both passwords allow access to privileged exec mode
the enable secret password command is newer and always encrypted by default
if you set enable password and then set enable secret password,
only the secret password will apply
to set a passowrd, provide it as an argument at the end of either commmand
11. Descrbie the configuration and use of banners
Banners provide information to users accessing the device and can be displayed at various login prompts.
They are configured with the banner command and a keyword describing the specific type of banner
Michael(config)#banner ?
login Set login banner
motd Set Message of the Day banner
Michael(config)#
banner motd @
Enter TEXT message. End with the character '@'.
the '@' is the character I chose as delimiter to end the input-- required as third arg in the commmand
hi this is the motd banner 1-16-22 @
Michael(config)#
exit
Michael#
%SYS-5-CONFIG_I: Configured from console by console
exit
Michael con0 is now available
Press RETURN to get started.
hi this is the motd banner 1-16-22
Michael>
12. Set the enable secret on a router
Michael(config)#
enable secret 1234
note the word PASSWORD is not used for the secret command
13. Set the auxillary and console passwords on a router
User mode passwords are assigned by using the line command
There are three lines: aux, console, and vty
aux
set user-mode password for the auxillary port. Usually used for attaching modem to router,
but can also be used as a console
Michael(config)
line aux 0 (0 because there is only one aux port)
Michael(config-line)
password aux1234
Michael(config-line)
login enables login
console
set's a console user-mode password
Michael(config)
line console 0 (0 because there is only one console port)
Michael(config-line)
password console1234
Michael(config-line)
login enables login
14. Set the Telnet password on a router (pg 230)
vty
sets a telnet user-mode password
Michael(config-line)
line vty 0 ?
% Unrecognized command (help fails-- only works from configure terminal mode)
Michael(config-line)
exit
Michael(config)
line vty 0 ? find out the expected param, and as a bonus- how many lines you have (varies by device)
<1-1180> Last Line Number the command expects a FIRST and LAST line number
Michael(config)
line vty 0 1180
Michael(config-line)
password telnet1234 set the password
Michael(config-line)
login enable login
NOTE if the telnet password isnt set, access will be denied:
Michael#
telnet SFRouter
Tying SF Router (10.0.0.1)..Open
Passowrd required, but none set
[Connection to SFRouter closed by foreing host]
Michael#
WORKAROUND- you can tell the router to allow Telnet connections without a password by
using the no login command
Michael(config-line)#
line vty 0 4
Michael(config-line)#
no login
15. Describe the advantages of using Secure Shell and list its requirements
Uses encrypted keys to send data so that usernames and passwords are not sent in the clear.
It requires that a hostname and domain name be configured and that encryption keys be generated.
16. Describe the process of preparing an interface for use
You must configure it with an IP address and subnet mask in the same subnet
of the hosts that will be connecting to the switch that is connected to
that interface.
It must be enabled with the no shutdown command
A serial interface that is connected back to back with another router serial
interface must also be configured with a clock rate on the DCE end of the serial cable
17. Understand how to troubleshoot a serial link problem
show interface serial 0
down, line protocol is down
indicates physical layer problem
show interface serial 0
up, line protocol is down
indicates link layer problem problem
18. Understand how to verify your router with the show interfaces command
shows the statistics for the interfaces on the router, if they are shut down,
and what their ip addresses are.
Michael#show interfaces
GigabitEthernet0/0 is administratively down, line protocol is down (disabled)
Hardware is CN Gigabit Ethernet, address is 00d0.bca2.9601 (bia 00d0.bca2.9601)
MTU 1500 bytes, BW 1000000 Kbit, DLY 10 usec,
reliability 255/255, txload 1/255, rxload 1/255
Encapsulation ARPA, loopback not set
Keepalive set (10 sec)
Full-duplex, 100Mb/s, media type is RJ45
output flow-control is unsupported, input flow-control is unsupported
ARP type: ARPA, ARP Timeout 04:00:00,
Last input 00:00:08, output 00:00:05, output hang never
Last clearing of "show interface" counters never
Input queue: 0/75/0 (size/max/drops); Total output drops: 0
Queueing strategy: fifo
Output queue :0/40 (size/max)
5 minute input rate 0 bits/sec, 0 packets/sec
5 minute output rate 0 bits/sec, 0 packets/sec
0 packets input, 0 bytes, 0 no buffer
Received 0 broadcasts, 0 runts, 0 giants, 0 throttles
0 input errors, 0 CRC, 0 frame, 0 overrun, 0 ignored, 0 abort
0 watchdog, 1017 multicast, 0 pause input
0 input packets with dribble condition detected
0 packets output, 0 bytes, 0 underruns
0 output errors, 0 collisions, 1 interface resets
0 unknown protocol drops
0 babbles, 0 late collision, 0 deferred
0 lost carrier, 0 no carrier
0 output buffer failures, 0 output buffers swapped out
GigabitEthernet0/1 is administratively down, line protocol is down (disabled)
Hardware is CN Gigabit Ethernet, address is 00d0.bca2.9602 (bia 00d0.bca2.9602)
MTU 1500 bytes, BW 1000000 Kbit, DLY 10 usec,
reliability 255/255, txload 1/255, rxload 1/255
Encapsulation ARPA, loopback not set
Keepalive set (10 sec)
Full-duplex, 100Mb/s, media type is RJ45
output flow-control is unsupported, input flow-control is unsupported
ARP type: ARPA, ARP Timeout 04:00:00,
Last input 00:00:08, output 00:00:05, output hang never
Last clearing of "show interface" counters never
Input queue: 0/75/0 (size/max/drops); Total output drops: 0
Queueing strategy: fifo
Output queue :0/40 (size/max)
5 minute input rate 0 bits/sec, 0 packets/sec
5 minute output rate 0 bits/sec, 0 packets/sec
0 packets input, 0 bytes, 0 no buffer
Received 0 broadcasts, 0 runts, 0 giants, 0 throttles
0 input errors, 0 CRC, 0 frame, 0 overrun, 0 ignored, 0 abort
0 watchdog, 1017 multicast, 0 pause input
0 input packets with dribble condition detected
0 packets output, 0 bytes, 0 underruns
0 output errors, 0 collisions, 1 interface resets
0 unknown protocol drops
0 babbles, 0 late collision, 0 deferred
0 lost carrier, 0 no carrier
0 output buffer failures, 0 output buffers swapped out
Vlan1 is administratively down, line protocol is down
Hardware is CPU Interface, address is 00d0.ff77.0c9a (bia 00d0.ff77.0c9a)
MTU 1500 bytes, BW 100000 Kbit, DLY 1000000 usec,
reliability 255/255, txload 1/255, rxload 1/255
Encapsulation ARPA, loopback not set
ARP type: ARPA, ARP Timeout 04:00:00
Last input 21:40:21, output never, output hang never
Last clearing of "show interface" counters never
Input queue: 0/75/0/0 (size/max/drops/flushes); Total output drops: 0
Queueing strategy: fifo
Output queue: 0/40 (size/max)
5 minute input rate 0 bits/sec, 0 packets/sec
5 minute output rate 0 bits/sec, 0 packets/sec
1682 packets input, 530955 bytes, 0 no buffer
Received 0 broadcasts (0 IP multicast)
0 runts, 0 giants, 0 throttles
0 input errors, 0 CRC, 0 frame, 0 overrun, 0 ignored
563859 packets output, 0 bytes, 0 underruns
0 output errors, 23 interface resets
0 output buffer failures, 0 output buffers swapped out
19. Describe how to view, edit, delete, and save a configuration
show running-config
show startup-config
copy running-config startup-config
erase startup-config
Written Lab 6.0
1. What command is used to set a serial interface to provide clocking to another router at 64kb?
router(config)
clock rate 64000
2. If you telnet into a router and get the response connection refused, password not set, what
commands would you execute on the destination router to stop receiving this message and not
be prompted for a password?
router(config)#
line vty ?
<0-15> First Line number
router(config)#
line vty 0 15
router(config-line)#
no login
3. If you type show inter ethernet 0 and notice the port is administratively down,
what commands would you execute to enable the interface?
router#
show interfaces
GigabitEthernet0/0/0 is administratively down, line protocol is down (disabled)
[output cut]
GigabitEthernet0/0/1 is administratively down, line protocol is down (disabled)
[output cut]
GigabitEthernet0/0/2 is administratively down, line protocol is down (disabled)
[output cut]
Vlan1 is administratively down, line protocol is down
[output cut]
router#
show interface gigabitethernet 0/0/0
GigabitEthernet0/0/0 is administratively down, line protocol is down (disabled)
[output cut]
router#
configure terminal
router(conf)#
interface gigabitethernet 0/0/0
router(conf-if)#
no shutdown
%LINK-5-CHANGED: Interface GigabitEthernet0/0/0, changed state to up
router(conf-if)#
do show int g0/0/0
GigabitEthernet0/0/0 is up, line protocol is down (disabled)
[output cut]
4. If you wanted to delete the configuration store in NVRAM, what command to use?
router#
erase ?
startup-config Erase contents of configuration memory
router#
erase startup-config
Erasing the nvram filesystem will remove all configuration files! Continue? [confirm]
[OK]
Erase of nvram: complete
%SYS-7-NV_BLOCK_INIT: Initialized the geometry of nvram
router#
5. If you wanted to set the user-mode password to todd for the console port,
what command to use?
router#
configure terminal
router(conf)#
line console 0 there is only one console port, "0"
router(conf)#
login tells the port to prompt for authentication
note that this will not work properly unless you also apply a password
router(conf)#
password todd
6. If you wanted to set the enable secret password to cisco, what command to use?
router#
configure terminal
router(conf-t)#
enable secret cisco
7. If you want to determine if serial interface 0/2 should provide clocking, what command to use?
router#
show controllers ?
Ethernet IEEE 802.3
FastEthernet FastEthernet IEEE 802.3
GigabitEthernet GigabitEthernet IEEE 802.3z
Serial Serial
<cr>
router#
show controllers serial 0/2
packet tracer 4300 router not giving output
8. What command would you use to see the terminal size history?
router#
show terminal
Line 0, Location: , Type:
Length: 24 lines, Width: 80 columns
Baud rate (TX/RX) is 9600/9600, no parity, 1 stopbits, 8 databits
Status: PSI Enabled, Ready, Active, Automore On
Capabilities: none
Modem state: Ready
Modem hardware state: CTS* noDSR DTR RTS
Special Chars: Escape Hold Stop Start Disconnect Activation
^^x none - - none
Timeouts: Idle EXEC Idle Session Modem Answer Session Dispatch
00:10:00 never none not set
Idle Session Disconnect Warning
never
Login-sequence User Response
00:00:30
Autoselect Initial Wait
not set
Modem type is unknown.
Session limit is not set.
Time since activation: 00:03:04
Editing is enabled.
History is enabled, history size is 10.
DNS resolution in show commands is enabled
Full user help is disabled
Allowed input transports are All.
Allowed output transports are pad telnet rlogin.
Preferred transport is telnet.
No output characters are padded
No special data dispatching characters
9. You want to reinitizalize the router and totally replace the running-config with
the current startup-config. What command to use?
router#
reload
System configuration has been modified. Save? [yes/no]:
Proceed with reload? [confirm]
Initializing Hardware ...
Checking for PCIe device presence...done
System integrity status: 0x610
Rom image verified correctly
System Bootstrap, Version 16.7(3r), RELEASE SOFTWARE
Copyright (c) 1994-2018 by cisco Systems, Inc.
Current image running: Boot ROM0
Last reset cause: LocalSoft
Cisco ISR4331/K9 platform with 4194304 Kbytes of main memory
no valid BOOT image found
Final autoboot attempt from default boot device...
Located isr4300-universalk9.16.06.04.SPA.bin
############################
Package header rev 1 structure detected
IsoSize = 550114467
Calculating SHA-1 hash...Validate package: SHA-1 hash:
calculated 444F4D02:44C58887:D9C8942B:C557D3CF:2A14247E
expected 444F4D02:44C58887:D9C8942B:C557D3CF:2A14247E
RSA Signed RELEASE Image Signature Verification Successful.
Image validated
Restricted Rights Legend
Use, duplication, or disclosure by the Government is
subject to restrictions as set forth in subparagraph
(c) of the Commercial Computer Software - Restricted
Rights clause at FAR sec. 52.227-19 and subparagraph
(c) (1) (ii) of the Rights in Technical Data and Computer
Software clause at DFARS sec. 252.227-7013.
cisco Systems, Inc.
170 West Tasman Drive
San Jose, California 95134-1706
Cisco IOS Software[Everest], ISR Software(X86_64_LINUX_IOSD - UNIVERSALK9 - M), Version 16.6.4, RELEASE SOFTWARE(fc3)
Technical Support : http://www.cisco.com/techsupport
Copyright(c) 1986 - 2018 by Cisco Systems, Inc.
Compiled Sun 08 - Jul - 18 04:33 by mcpre
Cisco IOS - XE software, Copyright(c) 2005 - 2018 by cisco Systems, Inc.
All rights reserved.Certain components of Cisco IOS - XE software are
licensed under the GNU General Public License("GPL") Version 2.0.The
software code licensed under GPL Version 2.0 is free software that comes
with ABSOLUTELY NO WARRANTY.You can redistribute and / or modify such
GPL code under the terms of GPL Version 2.0.For more details, see the
documentation or "License Notice" file accompanying the IOS - XE software,
or the applicable URL provided on the flyer accompanying the IOS - XE
software.
This product contains cryptographic features and is subject to United
States and local country laws governing import, export, transfer and
use. Delivery of Cisco cryptographic products does not imply
third-party authority to import, export, distribute or use encryption.
Importers, exporters, distributors and users are responsible for
compliance with U.S. and local country laws. By using this product you
agree to comply with applicable laws and regulations. If you are unable
to comply with U.S. and local laws, return this product immediately.
A summary of U.S. laws governing Cisco cryptographic products may be found at:
http://www.cisco.com/wwl/export/crypto/tool/stqrg.html
If you require further assistance please contact us by sending email to
export@cisco.com.
cisco ISR4331/K9 (1RU) processor with 1795999K/6147K bytes of memory.
Processor board ID FLM232010G0
3 Gigabit Ethernet interfaces
32768K bytes of non-volatile configuration memory.
4194304K bytes of physical memory.
3207167K bytes of flash memory at bootflash:.
0K bytes of WebUI ODM Files at webui:.
--- System Configuration Dialog ---
Would you like to enter the initial configuration dialog? [yes/no]:
10. How would you set the name of a router to Chicago?
router#
configure terminal
router(config)#
hostname Chicago
Chicago(config)#
Hands-on Lab 6.1 Erasing an Existing Configuration
router>
enable
router#
erase startup-config
Erasing the nvram filesystem will remove all configuration files! Continue? [confirm]
[OK]
Erase of nvram: complete
%SYS-7-NV_BLOCK_INIT: Initialized the geometry of nvram
router#
Hands-on Lab 6.2 Exploring User, Privileged, and Configuration Modes
user mode
router>
?
<1-99> Session number to resume
connect Open a terminal connection
disable Turn off privileged commands
disconnect Disconnect an existing network connection
enable Turn on privileged commands
exit Exit from the EXEC
logout Exit from the EXEC
ping Send echo messages
resume Resume an active network connection
show Show running system information
ssh Open a secure shell client connection
telnet Open a telnet connection
terminal Set terminal line parameters
traceroute Trace route to destination
user mode
router>
enable
privileged exec mode
router#
?
<1-99> Session number to resume
auto Exec level Automation
clear Reset functions
clock Manage the system clock
configure Enter configuration mode
connect Open a terminal connection
copy Copy from one file to another
debug Debugging functions (see also 'undebug')
delete Delete a file
dir List files on a filesystem
disable Turn off privileged commands
disconnect Disconnect an existing network connection
enable Turn on privileged commands
erase Erase a filesystem
exit Exit from the EXEC
logout Exit from the EXEC
mkdir Create new directory
more Display the contents of a file
no Disable debugging informations
ping Send echo messages
reload Halt and perform a cold restart
resume Resume an active network connection
rmdir Remove existing directory
send Send a message to other tty lines
setup Run the SETUP command facility
show Show running system information
ssh Open a secure shell client connection
telnet Open a telnet connection
terminal Set terminal line parameters
traceroute Trace route to destination
undebug Disable debugging functions (see also 'debug')
vlan Configure VLAN parameters
write Write running configuration to memory, network, or terminal
router#
config
Configuring from terminal, memory, or network [terminal]?
terminal is the default, enter to select
router(config)#
?
aaa Authentication, Authorization and Accounting.
access-list Add an access list entry
banner Define a login banner
bba-group Configure BBA Group
boot Modify system boot parameters
cdp Global CDP configuration subcommands
class-map Configure Class Map
clock Configure time-of-day clock
config-register Define the configuration register
crypto Encryption module
default Set a command to its defaults
do To run exec commands in config mode
dot11 IEEE 802.11 config commands
enable Modify enable password parameters
end Exit from configure mode
exit Exit from configure mode
flow Global Flow configuration subcommands
hostname Set system's network name
interface Select an interface to configure
ip Global IP configuration subcommands
ipv6 Global IPv6 configuration commands
key Key management
license Configure license features
line Configure a terminal line
lldp Global LLDP configuration subcommands
logging Modify message logging facilities
login Enable secure login checking
mac-address-table Configure the MAC address table
no Negate a command or set its defaults
ntp Configure NTP
parser Configure parser
policy-map Configure QoS Policy Map
port-channel EtherChannel configuration
priority-list Build a priority list
privilege Command privilege parameters
queue-list Build a custom queue list
radius RADIUS server configuration command
radius-server Modify Radius query parameters
router Enable a routing process
secure Secure image and configuration archival commands
security Infra Security CLIs
service Modify use of network based services
snmp-server Modify SNMP engine parameters
spanning-tree Spanning Tree Subsystem
tacacs-server Modify TACACS query parameters
username Establish User Name Authentication
vpdn Virtual Private Dialup Network
vpdn-group VPDN group configuration
router(conf)#
interface g0/0/0
router(conf-if)#
?
arp Set arp type (arpa, probe, snap) or timeout
bandwidth Set bandwidth informational parameter
cdp CDP interface subcommands
channel-group Add this interface to an Etherchannel group
crypto Encryption/Decryption commands
custom-queue-list Assign a custom queue list to an interface
delay Specify interface throughput delay
description Interface specific description
duplex Configure duplex operation.
exit Exit from interface configuration mode
fair-queue Enable Fair Queuing on an Interface
hold-queue Set hold queue depth
ip Interface Internet Protocol config commands
ipv6 IPv6 interface subcommands
lldp LLDP interface subcommands
mac-address Manually set interface MAC address
media-type Configure media type
mtu Set the interface Maximum Transmission Unit (MTU)
no Negate a command or set its defaults
pppoe pppoe interface subcommands
pppoe-client pppoe client
priority-group Assign a priority group to an interface
service-policy Configure QoS Service Policy
shutdown Shutdown the selected interface
speed Configure speed operation.
standby HSRP interface configuration commands
tx-ring-limit Configure PA level transmit ring limit
router(conf-if)#
exit
back one level
router(conf)#
exit
back one level
router#
disable
back to user mode
router>
Hands-on Lab 6.3 Using the Help and Editing Features
router#
?
router#
cl?
clear clock
router#
clock ?
set Set the date and time
router#
clock set 10:30:30 ?
<1-31> Day of the month
MONTH Month of the year
router#
clock set 10:30:30 17 January 2022
router#
router#
show clock
10:31:33.95 UTC Mon Jan 17 2022
keyboard commands
ctrl + A
beginning of line
ctrl + E
end of line
ctrl + B
back one character
ctrl + F
forward one character
ctrl + P
paste previous command
TAB
complete a partially typed command
router#
terminal no editing
turns off the keyboard shortcuts
router#
terminal editing
turns on the keyboard shortcuts
router#
show history
shows last 10 commands by default
router#
terminal history size 20
sets the history size to 20
Hands-on Lab 6.4 Saving a Router Configuration
router#
show startup-config
"startup config" AKA NVRAM
Using 672 bytes
!
version 16.6.4
no service timestamps log datetime msec
no service timestamps debug datetime msec
no service password-encryption
!
hostname Router
!
!
!
!
!
!
!
!
no ip cef
no ipv6 cef
!
!
!
!
!
!
!
!
!
!
!
!
spanning-tree mode pvst
!
!
!
!
!
!
interface GigabitEthernet0/0/0
no ip address
duplex auto
speed auto
shutdown
!
interface GigabitEthernet0/0/1
no ip address
duplex auto
speed auto
shutdown
!
interface GigabitEthernet0/0/2
no ip address
duplex auto
speed auto
shutdown
!
interface Vlan1
no ip address
shutdown
!
ip classless
!
ip flow-export version 9
!
!
!
!
!
!
!
!
line con 0
!
line aux 0
!
line vty 0 4
login
line vty 5 15
login
!
!
!
end
to copy a running config to NVRAM:
router#
copy running-config startup-config
to erase NVRAM:
router#
erase startup-config
router#
erase startup-config
Erasing the nvram filesystem will remove all configuration files! Continue? [confirm]
[OK]
Erase of nvram: complete
%SYS-7-NV_BLOCK_INIT: Initialized the geometry of nvram
router#
show startup-config
startup-config is not present
router#
reload
Proceed with reload? [confirm]
[output cut]
Would you like to enter the initial configuration dialog? [yes/no]:
Hands-on Lab 6.5 Setting Passwords
add a secret password
router(config)#
enable secret 1234
remove the secret password
router(config)#
no enable secret
Note youre not prompted for the secret, since you already had to provide
it in order to enter conf mode
add a regular password
router(config)#
enable password 4321
Can coexist with the secret password, but the two passwords must be different
----------------------------------------------------------------------
add password for Telnet aka VTY
router(config)#
line vty 0 15
16 virtual telnet lines on this router
We can set the whole range, a portion of the range, or a single line
router(config)#
login activate authentication
router(config)#
password telnet123
----------------------------------------------------------------------
add password for Auxiliary
router(config)#
line aux 0 there's only sone aux line
router(config)#
login activate authentication
router(config)#
password aux123
----------------------------------------------------------------------
add password for Console
router(config)#
line console 0 there's only one console line
router(config)#
login activate authentication
router(config)#
password console123
router(config)#
exec-timeout 0 0 min/sec
stop the console from timing out and logging you out
router(config)#
logging synchronous
dont overwrite input commands with console messages
Hands-on Lab 6.6 Setting the Hostname, Descriptions, IP Address, and Clock Rate
set router name
router(config)#
hostname routerA
------------------------------------------
set motd banner
routerA(config)#
banner ?
login Set login banner
motd Set Message of the Day banner
router(config)#
banner motd #
Enter TEXT message. End with the character '#'.
welcome to the router #
router(config)#
------------------------------------------
remove the banner
router(config)#
no banner motd
------------------------------------------
set login banner
router(config)#
banner login #
Enter TEXT message. End with the character '#'.
please login now #
router(config)#
------------------------------------------
add an IP address to an interface
router(config)#
do show interfaces use "do" to enable this command within config mode
GigabitEthernet0/0/0 is administratively down, line protocol is down (disabled)
---cut---
GigabitEthernet0/0/1 is administratively down, line protocol is down (disabled)
---cut---
GigabitEthernet0/0/2 is administratively down, line protocol is down (disabled)
---cut---
Vlan1 is administratively down, line protocol is down
router(config)#
interface g0/0/0
router(config-if)#
ip address 1.1.1.1 255.255.0.0
router(config-if)#
no shutdown
%LINK-5-CHANGED: Interface GigabitEthernet0/0/0, changed state to up
router(config-if)#
do show interfaces
GigabitEthernet0/0/0 is up, line protocol is down (disabled)
Internet address is 1.1.1.1/16
router(config-if)#
description WAN link to Miami
Chapter 6 Review Questions
1. You type show running-config and get this output:
---cut---
line console 0
Exec-timeout 1 44
Password 7 098C0BQR
Login
---cut---
What do the two numbers following the exec-timeout command mean?
minutes and seconds
2. Which connection method for connecting to a router is considered "out-of-band"?
auxiliary
The aux port can be configured to allow a modem to connect to the router.
It lets you dial up to a remote router in order to connect to the aux port if the router is down.
This method is considered "out of band" since its not connecting via "the network"
3. Which two commands are required when configuring SSH on your router?
ip domain-name name
username name password password
Example: Using SSH instead of Telnet
set your hostname, domain, and username
router(config)#
hostname Dallas
Dallas(config)#
ip domain-name Lammle.com
Dallas(config)#
username Michael password 1234
generate encryption keys
Dallas(config)#
crypto key generate rsa genral-keys modulus 1024
The name for the keys will be Michael.Lammle.com
% The key modulus size is 1024 bits
% Generating 1024 bit RSA keys, keys will be non-exportable...[ok]
*June 24 19:25:30.035: %SSH-5-ENABLED: SSH 1.99 has been enabled
enable SSH version 2
router(config)#
ssh version 2
connect to the vty lines of the router
router(config)#
line vty 0 1180
configure SSH and then Telnet as access protocols
router(config-line)#
transport input ssh telnet
4. Which command will show you wheter a DTE or a DCE cable is plugged into serial 0?
show controllers serial 0
will show whether DTE or DCE cable is connected to the interface
NOTE if it is a DTE connection you must add clocking with the
clock rate command
5. Which is a correct combination of file type and default location on a Cisco router?
IOS- flash memory
startup config- NVRAM
running config- RAM
6. You set the console password, but when you display the configuration, the password doesn't show up;
it looks like this:
[output cut]
line console 0
Exec-timeout 1 44
Password 7 098C0BQR
Login
[output cut]
What command would configure the password to be stored this way?
service password-encryption
7. Which command will configure all the default VTY ports on a router?
from global config mode:
line vty 0 4
will set all 5 default lines
8. Which command set the secret password to Cisco?
enable secret Cisco
9. If you wanted to see a message when logging into the router, which command would you use?
MOTD
10. Which prompt indicate that the router is currently in priviliged mode?
router#
11. What command do you type to save the configuration stored in RAM to NVRAM?
copy running-config startup-config
12. You try to telnet into SSFRouter from router to Corp and receive this message:
Corp#telnet SFRouter
Trying SFRouter (10.0.0.1)...Open
Password required, but none set
[Connection to SFRouter closed by foreing host]
Corp#
Which command sequence will address the problem correctly?
SFRouter(config)#
line vty 0 4
SFRouter(config-line)#
password password1234
SFRouter(config-line)#
login
13. Which command will delete the contents of NVRAM on a router?
erase startup-config
14. What is the problem with an interface if you type
show interface serial 9
and receive the following message?
Serial0 is administratively down, line protocol is down
is set to 'shut' by default, fix with no shut
15. Which command displays the configurable parameters and statistics of all interfaces on a router?
show interfaces
16. If you delete the contents of NVRAM and reboot the router, what mode will you be in?
setup mode
--- System Configuration Dialog ---
Would you like to enter the initial configuration dialog? [yes/no]:
17. You type the following command into the router and receive the following output:
Router#show serial 0/0
^
% Invalid input detected at '^' marker.
show interface serial 0/0
18. You type Router#sh ru and receive a % ambiguous command error.
Why did you receive this error?
not specific enough- there is more than one possible
show
command that starts with
ru
19. Which of the following commands will display the current
IP addressing and the layer 1 and 2 status of an interface?
show interfaces
GigabitEthernet0/0/0 is up, line protocol is down (disabled)
Hardware is ISR4331-3x1GE, address is 000d.bd45.db01 (bia 000d.bd45.db01)
Internet address is 1.1.1.1/16
MTU 1500 bytes, BW 1000000 Kbit, DLY 10 usec,
reliability 255/255, txload 1/255, rxload 1/255
Encapsulation ARPA, loopback not set
Keepalive not supported
Half Duplex, 1000Mbps, link type is auto, media type is Auto Select
output flow-control is on, input flow-control is on
ARP type: ARPA, ARP Timeout 04:00:00,
Last input 00:00:08, output 00:00:05, output hang never
Last clearing of "show interface" counters never
Input queue: 0/375/0 (size/max/drops); Total output drops: 0
Queueing strategy: fifo
Output queue :0/40 (size/max)
5 minute input rate 0 bits/sec, 0 packets/sec
5 minute output rate 0 bits/sec, 0 packets/sec
0 packets input, 0 bytes, 0 no buffer
Received 0 broadcasts (0 IP multicasts)
0 runts, 0 giants, 0 throttles
0 input errors, 0 CRC, 0 frame, 0 overrun, 0 ignored
0 watchdog, 1017 multicast, 0 pause input
0 input packets with dribble condition detected
0 packets output, 0 bytes, 0 underruns
0 output errors, 0 collisions, 1 interface resets
0 unknown protocol drops
0 babbles, 0 late collision, 0 deferred
0 lost carrier, 0 no carrier
0 output buffer failures, 0 output buffers swapped out
GigabitEthernet0/0/1 is administratively down, line protocol is down (disabled)
Hardware is ISR4331-3x1GE, address is 000d.bd45.db02 (bia 000d.bd45.db02)
MTU 1500 bytes, BW 1000000 Kbit, DLY 10 usec,
reliability 255/255, txload 1/255, rxload 1/255
Encapsulation ARPA, loopback not set
Keepalive not supported
output flow-control is on, input flow-control is on
ARP type: ARPA, ARP Timeout 04:00:00,
Last input 00:00:08, output 00:00:05, output hang never
Last clearing of "show interface" counters never
Input queue: 0/375/0 (size/max/drops); Total output drops: 0
Queueing strategy: fifo
Output queue :0/40 (size/max)
5 minute input rate 0 bits/sec, 0 packets/sec
5 minute output rate 0 bits/sec, 0 packets/sec
0 packets input, 0 bytes, 0 no buffer
Received 0 broadcasts (0 IP multicasts)
0 runts, 0 giants, 0 throttles
0 input errors, 0 CRC, 0 frame, 0 overrun, 0 ignored
0 watchdog, 1017 multicast, 0 pause input
0 input packets with dribble condition detected
0 packets output, 0 bytes, 0 underruns
0 output errors, 0 collisions, 1 interface resets
0 unknown protocol drops
0 babbles, 0 late collision, 0 deferred
0 lost carrier, 0 no carrier
0 output buffer failures, 0 output buffers swapped out
GigabitEthernet0/0/2 is administratively down, line protocol is down (disabled)
Hardware is ISR4331-3x1GE, address is 000d.bd45.db03 (bia 000d.bd45.db03)
MTU 1500 bytes, BW 1000000 Kbit, DLY 10 usec,
reliability 255/255, txload 1/255, rxload 1/255
Encapsulation ARPA, loopback not set
Keepalive not supported
Half Duplex, 1000Mbps, link type is auto, media type is unknown media type
output flow-control is on, input flow-control is on
ARP type: ARPA, ARP Timeout 04:00:00,
Last input 00:00:08, output 00:00:05, output hang never
Last clearing of "show interface" counters never
Input queue: 0/375/0 (size/max/drops); Total output drops: 0
Queueing strategy: fifo
Output queue :0/40 (size/max)
5 minute input rate 0 bits/sec, 0 packets/sec
5 minute output rate 0 bits/sec, 0 packets/sec
0 packets input, 0 bytes, 0 no buffer
Received 0 broadcasts (0 IP multicasts)
0 runts, 0 giants, 0 throttles
0 input errors, 0 CRC, 0 frame, 0 overrun, 0 ignored
0 watchdog, 1017 multicast, 0 pause input
0 input packets with dribble condition detected
0 packets output, 0 bytes, 0 underruns
0 output errors, 0 collisions, 1 interface resets
0 unknown protocol drops
0 babbles, 0 late collision, 0 deferred
0 lost carrier, 0 no carrier
0 output buffer failures, 0 output buffers swapped out
Vlan1 is administratively down, line protocol is down
Hardware is CPU Interface, address is 00d0.9715.9967 (bia 00d0.9715.9967)
MTU 1500 bytes, BW 100000 Kbit, DLY 1000000 usec,
reliability 255/255, txload 1/255, rxload 1/255
Encapsulation ARPA, loopback not set
ARP type: ARPA, ARP Timeout 04:00:00
Last input 21:40:21, output never, output hang never
Last clearing of "show interface" counters never
Input queue: 0/75/0/0 (size/max/drops/flushes); Total output drops: 0
Queueing strategy: fifo
Output queue: 0/40 (size/max)
5 minute input rate 0 bits/sec, 0 packets/sec
5 minute output rate 0 bits/sec, 0 packets/sec
1682 packets input, 530955 bytes, 0 no buffer
Received 0 broadcasts (0 IP multicast)
0 runts, 0 giants, 0 throttles
0 input errors, 0 CRC, 0 frame, 0 overrun, 0 ignored
563859 packets output, 0 bytes, 0 underruns
0 output errors, 23 interface resets
0 output buffer failures, 0 output buffers swapped out
show ip interface
GigabitEthernet0/0/0 is up, line protocol is down (disabled)
Internet address is 1.1.1.1/16
Broadcast address is 255.255.255.255
Address determined by setup command
MTU is 1500 bytes
Helper address is not set
Directed broadcast forwarding is disabled
Outgoing access list is not set
Inbound access list is not set
Proxy ARP is enabled
Security level is default
Split horizon is enabled
ICMP redirects are always sent
ICMP unreachables are always sent
ICMP mask replies are never sent
IP fast switching is disabled
IP fast switching on the same interface is disabled
IP Flow switching is disabled
IP Fast switching turbo vector
IP multicast fast switching is disabled
IP multicast distributed fast switching is disabled
Router Discovery is disabled
IP output packet accounting is disabled
IP access violation accounting is disabled
TCP/IP header compression is disabled
RTP/IP header compression is disabled
Probe proxy name replies are disabled
Policy routing is disabled
Network address translation is disabled
BGP Policy Mapping is disabled
Input features: MCI Check
WCCP Redirect outbound is disabled
WCCP Redirect inbound is disabled
WCCP Redirect exclude is disabled
GigabitEthernet0/0/1 is administratively down, line protocol is down (disabled)
Internet protocol processing disabled
GigabitEthernet0/0/2 is administratively down, line protocol is down (disabled)
Internet protocol processing disabled
Vlan1 is administratively down, line protocol is down
Internet protocol processing disabled
20. At which layer of the OSI model would you assume the problem is if you type
show interface serial 1
and receive the following message?
Serial 1 is down, line protocol is down
physical
if you see both interface and protocal down, it's physical
if you see serial1 is up but line protocol down, its data link- data-link keepalives are not being sent from the remote end
END CHAPTER 6
15 hours 1-15 thru 1-19-22
original total hours 63
2.5 hours review 12-21-22
review total hours 13.5
book page 274/822
Chapter 7 Notes - Managing a Cisco Internetwork
notes
Configuration Register
16 bits / 2 bytes... bit values from 15 to 0
uses Hexadecimal nibbles
Chapter 7 Exam Essentials - Managing a Cisco Internetwork
1. Define the Cisco router componenets
ROM
- used to start and maintain the router. Holds bootstrap, POST, mini-IOS
bootstrap
- stored in the microcode of the ROM. Finds where the IOS program is located and loads the file.
POST
- stored in the microcode of the ROM. Used to check the basic funtionality and determine which interfaces are present
ROM monitor
- stored in the microcode of the ROM. Used for manufacturing, testing, and troubleshooting
mini-IOS
- Called the RXBOOT or 'bootloader'. It's a small OS in ROM that can be used to bring up an interface and load a Cisco IOS into flash memory
-----------------------------------------------------------------------------------------------------------------------
flash memory
- EEPROM- default location of the IOS
NVRAM
-holds the router/switch configuration
not erased when the device is reloaded
configuration register
- controls how the router boots up
Tells the router to load the IOS from flash memory as well as to load the configuration from NVRAM
RAM
- used to hold packet buffers, ARP cache, routing tables and the data structures that allow the router to function.
running-config is stored in RAM
routers expand the IOS from flash into RAM at boot
2. Identify the steps in the router boot sequence
POST
bootstrap
load the IOS from flash into RAM
load the configuration file from NVRAM into RAM
running-config and the IOS are both now running in RAM
3. Understand configuration register commands and settings
0x2102 default- find the boot sequence in NVRAM
0x2101 boot from ROM
0x2142 do not load the startup-config in NVRAM. Used for password recovery
4.Perform password recovery
NOTE - this requires physical access to reboot the router
The default configuration register value is 0x2102 which tells the router to load a config stored
in NVRAM(startup-config).
To recover a password, we need to change the config register value to 0x2142 which tells the router to ignore the VRAM contents and load a 'non configured' OS.
"configurations" can be defined as any changes we make to the device: hostname, passwords, interfaces, etc
For this demo, our 4331 router is configured with the hostname 4331 and the password 1234
4331(config)#
enable secret 1234
4331#
copy run start
Destination filename [startup-config]?
Building configuration...
[OK]
Step 1. Bounce the router, then interrupt the boot sequence by performing a break.
Initializing Hardware ...
Checking for PCIe device presence...done
System integrity status: 0x610
Rom image verified correctly
System Bootstrap, Version 16.7(3r), RELEASE SOFTWARE
Copyright (c) 1994-2018 by cisco Systems, Inc.
Current image running: Boot ROM0
Last reset cause: LocalSoft
Cisco ISR4331/K9 platform with 4194304 Kbytes of main memory
no valid BOOT image found
Final autoboot attempt from default boot device...
Located isr4300-universalk9.16.06.04.SPA.bin
###############################################################
CTRL+BREAK
monitor: command "boot" aborted due to user interrupt
rommon 1 >
Step 2. We're given a ROM MONITOR prompt which allows us to change the configuration register (Cisco ISR/2600 Series commands).
rommon 1 >
confreg 0x2142
rommon 1 >
reset must reset or power cycle router to apply the change
system will ask if you want Setup Mode - that is the the generic startup message,
since we are bypassing the startup configuration. Our answer is no.--- System Configuration Dialog ---
Would you like to enter the initial configuration dialog? [yes/no]:
N + Enter
we now have full access to this non-configured OS. We can enter priviliged mode with no password.
Router>
enable
Router#
show version
Cisco IOS Software [Everest], ISR Software (X86_64_LINUX_IOSD-UNIVERSALK9-M), Version 16.6.4,RELEASE SOFTWARE (fc3)
[cut]
Configuration register is 0x2142
this verifies that our configs are not in use (no hostname in the prompt) and our config register has been changed to 2142
HERE IS THE KEY-
we are going to restore the configuration by copying the "startup-config"
into our live environment AKA the "running-config"
Router#
copy startup-config running-config
Destination filename [running-config]? Enter
695 bytes copied in 0.416 secs (1670 bytes/sec)
4331#
%SYS-5-CONFIG_I: Configured from console by console
we get our old prompt back:
4331#
Note that we DO NOT know the password required to enter privliged mode that we are currently inside of!
if you exit this prompt back out to user mode, you will not be able to get back in without the password.
We entered privileged mode from within the generic configuration. Then inserted our saved configuration 'beneath' our prompt.
This action does not kick you out of priv. mode, which will allow us to RESET the password for our saved configuration.
set the new password
4331(config)#
enable secret 0000
set the config register back to default, to point back to NVRAM on the next reboot
(you can do this from global config mode as well as rommon mode)
4331(config)#
config-register 0x2102
4331#
show version
[cut]
Configuration register is 0x2142 (will be 0x2102 at next reload)
now we can save the config with the updated password.
Two ways to do it-
4331#
write
Building configuration...
[OK]
OR
4331#
copy running-config startup-config
Destination filename [startup-config]?
Building configuration...
[OK]
reload the router and your new password will be saved into your config
4331#
reload
this feature is helpful since Cisco equipment tends to run for long stretches of time (years) and the passwords get forgotten.
Thank you to Jeremy Cioara for help on this topic
5. Back up an IOS image
we can copy a router's configuration to a TFTP server with either of these commands:
Router#
copy running-config tftp
Router#
copy startup-config tftp
to verify either of the configs before backup, we can use these commands:
Router#
show running-config
Router#
show startup-config
6. Restore or upgrade an IOS image - note we are talking about the IOS itself, not the 'configuration'
We will download the IOS file from TFTP server to flash memory on the router. Command requires the IP of the TFTP host and the filename
Before we begin we must make sure the IOS file is in the default TFTP directory on the host.
The command will not ask you where the file is on the host....
Router#
copy tftp flash
Address or name of remote host []? 1.1.1.2
Source filename []? c2800nm-advsecurityk9-mz.124.12.bin
Destination filename[c2800nm-advsecurityk9-mz.124.12.bin]? ENTER
%Warning this is a file already existing with this name
Do you want to over write [confirm] ENTER
Accessing tftp://1.1.1.2/c2800nm-advsecurityk9-mz.124-12.bin...
Loading c2800nm-advsecurityk9-mz.124-12.bin from 1.1.1.2 (via FastEthernet0/0): !!!!!!!!!!!!!!!!
!!!!!!!!!!!!!!!!!!!!!!!!!!
[OK - 21710744 bytes]
21710744 bytes copied in 82.880 secs (261954 bytes/sec)
Router#
to restore configuration:
restore from startup-config:
Router#
copy startup-config running-config
or we can restore from a backup on TFTP server
Router#
copy tftp running-config
Address or name of remote host []? 1.1.1.2
Source filename []? todd-confg
Destination filename[running-config?] ENTER
Accessing tftp://1.1.1.2/todd-confg...
Loading todd-confg from 1.1.12 (civa FastEthernet0/0): !
[OK - 776 bytes]
776 bytes copied in 9.212 secs (84 bytes/sec)
Router#
*Jan 23 12:40:00.000: %SYS-5-CONFIG_I: Configured from tftp://1.1.1.2/todd-confg by console
Router#
7. Describe best practices to prepare to back up an IOS image to a network server
Ensure you can acccess the network server, and there is adequate storage space.
Verify the file naming and path requirements
have the source IOS file in the default TFTP directory
8. Save the configuration of a router
Router#
copy running-config startup-config
9. Erase the configuration of a router
Router#
erase startup-config
10. Understand and use the Cisco IFS file system management commands
IFS = IOS File System
UNIX Based
dir
show files in a directory. Requires privliged mode. If not path is given as argument, you'll see the directory of 'flash' root.
NOTE the file paths use a URL format
R1#
dir
Directory of flash:/
3 -rw- 486899872 <no date> isr4300-universalk9.16.06.04.SPA.bin
2 -rw- 28282 <no date> sigdef-category.xml
1 -rw- 227537 <no date> sigdef-default.xml
3249049600 bytes total (2761893909 bytes free)
-------------------------------------------------------------------------------------------------------
copy
often used to backup, restore, or ugprade the IOS
first arg = source
second arg = destination
R1#
copy
source
destination
-------------------------------------------------------------------------------------------------------
more
display a text file
-------------------------------------------------------------------------------------------------------
show file
display a text file
-------------------------------------------------------------------------------------------------------
delete
remote file (may also need to use SQUEEZE to free up the space)
-------------------------------------------------------------------------------------------------------
erase/format
may delete flash drive depending on system
-------------------------------------------------------------------------------------------------------
cd/pwd
change directory / print working directory
-------------------------------------------------------------------------------------------------------
mkdir/rmdir
create / delete directories
11. Describe the value of CDP
Cisco Discovery Protocol - helps to document / troubleshoot the network
See lab 7.4
12. List the information provided by the output of
show cdp neighbors
device ID
local interface
holdtime
capabilility
platform
port ID (remote interface)
13. Understand how to establish a Telnet session with multiple routers simultaneously
Press Ctrl+Shift+6 then x to exit a telnet session without closing it
14. Identify current Telnet sessions
R1#
show sessions
15. Build a static host table on a router
R1#
ip host
host_name
ip_address
manually assigning an IP to a host name. You can apply multiple IP's to one host entry
see lab 7.6
16. Verify the host table on a router
R1#
show hosts
17. Describe the function of the ping command
Packet Internet Groper uses ICMP echo requests and replies to verify an active IP address on a network
18. Ping a vaild host ID from the correct prompt
R1#
ping 1.1.1.1
Note PING works from user or privliged mode but NOT config mode
Chapter 7 Written Lab 7.1 - IOS Management
TFTP Server Setup - network layout is not from book- I created this network to help demo the written lab
TFTP server is already created and switched on by default within the 'Server' object
Router Configuration
R1(config)#
int g0/0/1
R1(config-if)#
ip address 10.1.1.4 255.255.255.0
R1(config-if)#
no shutdown
%LINK-5-CHANGED: Interface GigabitEthernet0/0/1, changed state to up
%LINEPROTO-5-UPDOWN: Line protocol on Interface GigabitEthernet0/0/1, changed state to up
r1(config-if)#
do show ip int brief
Interface IP-Address OK? Method Status Protocol
GigabitEthernet0/0/0 unassigned YES manual administratively down down
GigabitEthernet0/0/1 192.1.1.4 YES NVRAM up up
GigabitEthernet0/0/2 unassigned YES NVRAM administratively down down
Vlan1 unassigned YES NVRAM administratively down down
Switch Configuration
SW1(config)#
int f0/1
SW1(config-if)#
no shutdown
%LINK-5-CHANGED: Interface FastEthernet0/1, changed state to up
%LINEPROTO-5-UPDOWN: Line protocol on Interface FastEthernet0/1, changed state to up
SW1(config-if)#
int f0/2
SW1(config-if)#
no shutdown
%LINK-5-CHANGED: Interface FastEthernet0/2, changed state to up
%LINEPROTO-5-UPDOWN: Line protocol on Interface FastEthernet0/2, changed state to up
Test connectivity to the server
R1#
ping 192.1.1.3
Type escape sequence to abort.
Sending 5, 100-byte ICMP Echos to 192.1.1.3, timeout is 2 seconds:
.!!!!
Success rate is 80 percent (4/5), round-trip min/avg/max = 0/1/6 ms
Find the name of the Router flash file
R1#
show flash
System flash directory:
File Length Name/status
3 486899872isr4300-universalk9.16.06.04.SPA.bin
2 28282 sigdef-category.xml
1 227537 sigdef-default.xml
[487155691 bytes used, 2761893909 available, 3249049600 total]
3.17338e+06K bytes of processor board System flash (Read/Write)
we need to paste that filename into our copy command below
1. command to copy a Cisco IOS to a TFTP server?
R1#
copy flash tftp
Source filename []? isr4300-universalk9.16.06.04.SPA.bin
Address or name of remote host []? 192.1.1.3
Destination filename [isr4300-universalk9.16.06.04.SPA.bin]? ENTER
Writing isr4300-universalk9.16.06.04.SPA.bin...!!!!!!!!!!!!!!!!
!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!
[OK - 486899872 bytes]
486899872 bytes copied in 12.364 secs (126865 bytes/sec)
the file appears on our server
2. command to copy a Cisco startup-config file to a TFTP server?
R1#
copy running-config tftp
Address or name of remote host []? 192.1.1.3
Destination filename [r1-confg]? ENTER
Writing running-config.....!!
[OK - 707 bytes]
707 bytes copied in 3 secs (235 bytes/sec)
the file appears on our server
OR
R1#
copy startup-config tftp
3. command to copy the startup-config file to DRAM?
R1#
copy startup-config running-config
the running configuration exists in DRAM
4. What is an older command that you can use to copy the startup-config file to DRAM?
R1#
config mem
(not supported by packet tracer)
5. What command can you use to see the neighbor router's IP address from your router prompt?
R1#
show cdp neighbor detail
OR
R1#
show cdp entry *
6. What command to see the hostname, local interface, platform, and remote port of a neighbor router?
R1#
show cdp neighbor
7. What keystrokes can you use to telnet into multiple devices simultaneously?
Ctrl + Shift + 6, then X
8. What command will show you your active Telnet connections to neighbor and remote devices?
R1#
show sessions
9. What command can you use to upgrade a Cisco IOS?
R1#
copy tftp flash
10. What command can you use to merge a backup configuration with the configuration in RAM?
R1#
copy tftp run
OR
R1#
copy start run
RAM = running configuration
Chapter 7 Written Lab 7.2 - Router Memory
Identify the location in a router where each of the files is stored by default:
1. Cisco IOS
flash
2. Bootstrap
ROM
3. Startup configuration
NVRAM
4. POST
ROM
5. Running configuration
RAM
6. ARP cache
RAM
7. Mini IOS
ROM
8. ROM Monitor
ROM
9. Routing tables
RAM
10. packet buffers
RAM
****dont make the mistake of thinking arp cache, routing tables, packet buffers, are stored somewhere other than RAM
they are considered part of running-config which exists in RAM
Chapter 7 Hands-on Labs
To complete these labs, we are going to need three routers and one TFTP server.
Here is the topology:
Server Configuration
ipv4 address: 193.1.1.2
subnet mask: 255.255.255.248
default gateway: 193.1.1.1
Switch Configuration
SW1#
interface range f0/1-2
SW1(config-if-range)#
no shut
Router Configurations
R1(config)#
int g0/0/0
R1(config)#
ip addr 193.1.1.9 255.255.255.248
R1(config)#
no shut
R1(config)#
int g0/0/1
R1(config)#
ip addr 193.1.1.1 255.255.255.248
R1(config)#
no shut
the server's default gateway
R2(config)#
int g0/0/0
R2(config)#
ip addr 193.1.1.10 255.255.255.248
R2(config)#
no shut
R2(config)#
int g0/0/1
R2(config)#
ip addr 193.1.1.17 255.255.255.248
R2(config)#
no shut
R3(config)#
int g0/0/0
R3(config)#
ip addr 193.1.1.18 255.255.255.248
R3(config)#
no shut
the segment between R1 and the server
network 193.1.1.0/29
block of 8
hosts .1, .2
the segment between R1 and R2
network 193.1.1.8/29
block of 8
hosts .9 , .10
the segment between the R2 and R3
network 193.1.1.16/29
block of 8
hosts .17 , .18
THIS IS INCORRECT!!!!
I have misunderstood the instructions.
the problem with this topology is that packets cannot pass through the routers. We dont have any ROUTING setup. ROUTING is covered in the next chapter.
For these labs, we dont need routing, but we need multiple routers to demo telnet and CDP. Here are the instructions:
my mistake was not putting all router interfaces in the same subnet. I tried to do this initially, but it wouldnt work because I had the routers linked together rather than connected by a switch.
The instructions say:
"Your PC and the router(s) are connected together with a switch"
this is the part I missed. The pc and all router interfaces should be on the same switch and the same network
Here is the corrected topology
Server Configuration
ipv4 address: 193.1.1.4
subnet mask: 255.255.255.248
default gateway: 193.1.1.1
Switch Configuration
SW1#
interface range f0/1-4
SW1(config-if-range)#
no shut
Router Configurations
R1(config)#
int g0/0/0
R1(config)#
ip addr 193.1.1.1 255.255.255.248
R1(config)#
no shut
the server's default gateway
R2(config)#
int g0/0/0
R2(config)#
ip addr 193.1.1.2 255.255.255.248
R2(config)#
no shut
R3(config)#
int g0/0/0
R3(config)#
ip addr 193.1.1.3 255.255.255.248
R3(config)#
no shut
Chapter 7 Hands-on Lab 7.1 Backing up your router IOS
1. verify connection to the server
R1#
ping 193.1.1.1
Type escape sequence to abort.
Sending 5, 100-byte ICMP Echos to 193.1.1.2, timeout is 2 seconds:
.!!!!
Success rate is 80 percent (4/5), round-trip min/avg/max = 0/1/5 ms
2. show contents of flash memory
R1#
show flash
System flash directory:
File Length Name/status
3 486899872isr4300-universalk9.16.06.04.SPA.bin
2 28282 sigdef-category.xml
1 227537 sigdef-default.xml
[487155691 bytes used, 2761893909 available, 3249049600 total]
3.17338e+06K bytes of processor board System flash (Read/Write)
show flash gives ALL of the files in flash memory
show version gives the current running file
3. show the IOS currently running
R1#
show version
Cisco IOS XE Software, Version 03.16.05.S - Extended Support Release
[cut]
ROM: IOS-XE ROMMON
Router uptime is 9 minutes, 39 seconds
Uptime for this control processor is 9 minutes, 39 seconds
System returned to ROM by power-on
System image file is "bootflash:/isr4300-universalk9.03.16.05.S.155-3.S5-ext.SPA.bin"
Last reload reason: PowerOn
[cut]
note that the file that is currently running is NOT located in the flash storage!!!
4. backup IOS from router to server
R1#
copy flash tftp
Source filename []?isr4300-universalk9.16.06.04.SPA.bin
Address or name of remote host []? 193.1.1.4
Destination filename [isr4300-universalk9.16.06.04.SPA.bin]? ENTER
Writing isr4300-universalk9.16.06.04.SPA.bin...!!!!!!!!!!!!!!!
[OK - 486899872 bytes]
486899872 bytes copied in 12.526 secs (125224 bytes/sec)
Chapter 7 Hands-on Lab 7.2 Upgrading or restoring your router IOS
1. verify connection to the server
R1#
ping 193.1.1.4
Type escape sequence to abort.
Sending 5, 100-byte ICMP Echos to 193.1.1.2, timeout is 2 seconds:
!!!!!
Success rate is 100 percent (5/5), round-trip min/avg/max = 0/0/1 ms
2. copy from tftp sever to flash
R1#
copy tftp flash TFTP comes first in the command since we are pulling from TFTP server.
In this command, remot host address is required before file name
Address or name of remote host []? 193.1.1.4
Source filename []?isr4300-universalk9.16.06.04.SPA.bin
Destination filename [isr4300-universalk9.16.06.04.SPA.bin]? ENTER
%Warning:There is a file already existing with this name
Do you want to over write? [confirm]
Accessing tftp://193.1.1.4/isr4300-universalk9.16.06.04.SPA-12-23-22...
Loading isr4300-universalk9.16.06.04.SPA-12-23-22.bin from 193.1.1.4: !!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!
[OK - 486899872 bytes]
486899872 bytes copied in 12.785 secs (122688 bytes/sec)
Chapter 7 Hands-on Lab 7.3 Backing up the router configuration
1. verify connection to the server
R1#
ping 193.1.1.2
Type escape sequence to abort.
Sending 5, 100-byte ICMP Echos to 193.1.1.4, timeout is 2 seconds:
!!!!!
Success rate is 100 percent (5/5), round-trip min/avg/max = 0/0/1 ms
2. copy running-confing to server
R1#
copy run tftp
Address or name of remote host []? 193.1.1.4
Destination filename [R1-confg]?ENTER "R1-confg" is the default name
Writing running-config...!!
[OK - 668 bytes]
668 bytes copied in 0.004 secs (167000 bytes/sec)
Chapter 7 Hands-on Lab 7.4 Using the Cisco Discovery Protocol (CDP)
R1#
show cdp
Global CDP information:
Sending CDP packets every 60 seconds
Sending a holdtime value of 180 seconds
Sending CDPv2 advertisements is enabled
R1#
show cdp interface
Vlan1 is administratively down, line protocol is down
Sending CDP packets every 60 seconds
Holdtime is 180 seconds
GigabitEthernet0/0/0 is up, line protocol is up
Sending CDP packets every 60 seconds
Holdtime is 180 seconds
GigabitEthernet0/0/1 is administratively down, line protocol is down
Sending CDP packets every 60 seconds
Holdtime is 180 seconds
GigabitEthernet0/0/2 is administratively down, line protocol is down
Sending CDP packets every 60 seconds
Holdtime is 180 seconds
R1#
show cdp entry *
Device ID: SW1
Entry address(es):
Platform: cisco 2960, Capabilities: Switch
Interface: GigabitEthernet0/0/0, Port ID (outgoing port): FastEthernet0/1
NOTE g0/0/0 is the outgoing port on this router, F0/1 is the port on the switch at other end
Holdtime: 157
Version :
Cisco IOS Software, C2960 Software (C2960-LANBASEK9-M), Version 15.0(2)SE4, RELEASE SOFTWARE (fc1)
Technical Support: http://www.cisco.com/techsupport
Copyright (c) 1986-2013 by Cisco Systems, Inc.
Compiled Wed 26-Jun-13 02:49 by mnguyen
advertisement version: 2
Duplex: full
R1#
show cdp entry neighbors
[no output]
R1#
show cdp neighbors detail
Device ID: SW1
Entry address(es):
Platform: cisco 2960, Capabilities: Switch
Interface: GigabitEthernet0/0/0, Port ID (outgoing port): FastEthernet0/1
Holdtime: 178
Version :
Cisco IOS Software, C2960 Software (C2960-LANBASEK9-M), Version 15.0(2)SE4, RELEASE SOFTWARE (fc1)
Technical Support: http://www.cisco.com/techsupport
Copyright (c) 1986-2013 by Cisco Systems, Inc.
Compiled Wed 26-Jun-13 02:49 by mnguyen
advertisement version: 2
Duplex: full
Chapter 7 Hands-on Lab 7.5 Using Telnet
enable telnet on R2 and set password
R2(config)#
line vty 0 15
R2(config-line)#
password telnet
R2(config-line)#
login
enable telnet on R3 and set password
R3(config)#
line vty 0 15
R3(config-line)#
password telnet
R3(config-line)#
login
note that the result of this command on each router, by default,
is to present all 15 lines in TWO SEPERATE chunks: 0-4 and 5-15
R3#
show run
[cut]
!
!
!
line con 0
!
line aux 0
!
line vty 0 4
password telnet
login
line vty 5 15
password telnet
login
!
!
!
end
--------------------------------------------------------------------------------
connect to R2 from R1
R1#
telnet 193.1.1.2
Trying 193.1.1..2 ...Open
User Access Verification
Password: telnet
prompt changes to R2 to indicate we are remoted in
R2>
exit the session
ctrl + shift + 6, x
prompt changes back to R1
R1#
--------------------------------------------------------------------------------
connect to R3 from R1
R1#
193.1.1.3 note that the word 'telnet' is not required bc we are still in telnet mode
Trying 193.1.1..3 ...Open
User Access Verification
Password: telnet
prompt changes to R3 to indicate we are remoted in
R3>
exit the session
ctrl + shift + 6, x
prompt changes back to R1
R1#
--------------------------------------------------------------------------------
We have exited the sessions, but they are still open
R1#
show sessions
Conn Host Address Byte Idle Conn Name
1 193.1.1.2 193.1.1.2 0 0 193.1.1.2
* 2 193.1.1.3 193.1.1.3 0 0 193.1.1.3
two telnet sessions- notice that the 'conn number' doesnt correspond to ip address in any way.
R1#
show users
Line User Host(s) Idle Location
* 0 con 0 193.1.1.2 00:00:03
193.1.1.3 00:00:43
this is saying one user is on this router, with two outbound connections (but it isnt showing that they are vty connections)
... they must both be considered 'console' connections outbound and are not considered 'vty' until they are received inbound
the asterisk means something different here than above... doesnt mean default(most recent)session... what does it mean?
back to R2
R2#
show users
Line User Host(s) Idle Location
* 4 vty 0 idle 00:00:00 193.1.1.1
Interface User Mode Idle Peer Address
this is saying that there is one (unnamed) user remoted in via line vty 4
back to R3
R3#
show users
Line User Host(s) Idle Location
* 4 vty 0 idle 00:00:00 193.1.1.1
Interface User Mode Idle Peer Address
this is saying that there is one (unnamed) user remoted in via line vty 4
-------------------------------------------------------------------------------------
Important Considerations:
-
asterisk indicates default session
-
when telnetting in, you will be in user mode. If there is no password already set for PRIVILEGED MODE, you will be unable to enter
-
be careful with 'exit'. it will exit the telnet session if you exit at priv. mode. Use 'disable' to leave priv mode.
-
after 'suspending' a session with ctrl+shift+6,x and youre back at your original priv. prompt, do not press enter to create line breaks-
rather than break lines as usual, the keystroke will cause this:
[Resuming connection 1 to 193.1.1.2 ... ]
prompt will sit here until you strike enter again, then you'll return to that session. What is actually happening is that
youre connecting to the 'default' telnet connection. The same behavior happens when youre at the 'show sessions' screen.
Even if you are not viewing active sessions, the enter key(twice) will connect you to the default session
-
you can use disconnect or exit to end a session
-
Ex: disconnect 1 at the show sessions screen
Chapter 7 Hands-on Lab 7.6 Resolving Hostnames
We're going to build a host table on R1 so we can connect to the other routers via hostname rather than type in the IP address
the command is ip host name arg ip arg
R1(config)#
ip host R2 193.1.1.2
R1(config)#
ip host R3 193.1.1.3
Now if we enter R2 or telnet R2 we get the telnet prompt
R1# R2
Trying 193.1.1.2 ...Open
User Access Verification
Password:
same for the PING command
R1# ping R2
Type escape sequence to abort.
Sending 5, 100-byte ICMP Echos to 193.1.1.2, timeout is 2 seconds:
!!!!!
Success rate is 100 percent (5/5), round-trip min/avg/max = 0/0/2 ms
R1#
show hosts
Default Domain is not set
Name/address lookup uses domain service
Name servers are 255.255.255.255
Codes: UN - unknown, EX - expired, OK - OK, ?? - revalidate
temp - temporary, perm - permanent
NA - Not Applicable None - Not defined
Host Port Flags Age Type Address(es)
R2 None (perm, OK) 0 IP 193.1.1.2
R3 None (perm, OK) 0 IP 193.1.1.3
R1#
telnet R2
R2>
CTRL + SHIFT + 6, X
R1#
telnet R3
R3>
CTRL + SHIFT + 6, X
R1#
show session
Conn Host Address Byte Idle Conn Name
1 R2 193.1.1.2 0 0 R2
* 2 R3 193.1.1.3 0 0 R3
Chapter 7 Review Questions
1. What does the command
confreg 0x2142
provide?
bypass startup-config, to allow password reset
2. Which command will copy the IOS to a backup host on your network?
copy flash tftp
3. You are troubleshooting a connectivity problem in your corporate network and want to isolate the problem. You suspect that a router on the route to an unreachable
network is at fault. What IOS user exec command should you issue?
traceroute
note this is not a priviliged mode command; it can be run from user mode
4. You copy a configuration from a network host to a router's RAM. The configuration looks correct, yet it is no working at all. What could the problem be?
when you perform a copy from a network host to a router, the interfaces are automatically shut down and have to be manually enabled with no shutdown
5. A network administrator wants to upgrade the IOS of a router without removing the image currently installed. What command will display the amount of memory consumed by the
current IOS image and indicate whether there is enough room available to hold both the current and new images?
show flash
6. The corporate office sends you a new router to connect, but upon connecting the console cable, you see that there is already a configuration on the router.
What should be done before a new configuration is entered in the router?
erase NVRAM and restart the router
erase startup-config
reload
7. Which command loads a new version of the Cisco IOS into a router?
copy tftp flash
8. Which command will show you the IOS version running on your router?
show version
9. What should the configuration register value be after you successfully complete the password recovery procedure and return the router to normal operation?
0x2102
10. You save the configuration on a router with the
copy running-config startup-config
command and reboot the router. The router, however, comes up with a blank configuration. What can the problem be?
wrong config register causing you to bypass startup-confing in NVRAM
11. If you want to have more than one Telnet session open at the same time, what keystroke combination would you use?
CTRL+SHIFT+6, X
12. You are unsuccessful in telnetting into a remote device, but you could telnet to the router earlier, However, you can still ping the remote device.
What can the problem be?
access control list could be filtering telnet
OR
the VTY password may not be set on the target
13. What information is displayed by the
show hosts
command?
gives info on temporary DNS entries and permanent name-to-address mappings created using the ip host command
14. Name three commands that can be used to check LAN connectivity problems on a router?
trace
show interfaces
show ip route
15. You telnet to a router and make your necessary changes; now you want to end the Telnet session. What command do you type in?
exit
16. You telnet into a remote device and type
debug ip rip
but no output from the
debug
command is seen. What could the problem be?
to see console messages through a telnet session, you must enter the command terminal monitor
17. Which command displays the configuration register setting?
show version
18. You need to gather the IP address of a remote switch that is located in Hawaii. What can you do to find the address?
show cdp neighbors detail
19. You have your laptop directly connected into a router's Ethernet port. Which are requirements for the
copy flash tftp
command to be successful?
have a TFTP server running on the laptop
laptop must have an IP on the same subnet as the router interface
give the IP address of the laptop when asked after entering the command
20. The configuration register setting of 0x2102 provides what function to a router?
points to NVRAM for startup-configuration AND boot sequence
END CHAPTER 7
26 hours 1-19 thru 1-26-22
original total hours 89
7 hours review 12-23-22
review total hours 20.5
book page 344/822
avg 15 min/page (reading and exercises/labs)
Chapter 8 Exercises
pg 374
before I begin to configure this network, I want to look closer at the HARDWARE
Todd mentions these routers:
2811 with four serial interfaces and switch module or wireless card
1841
while the book was published in 2011, both routers appear to be available in 2021 packet tracer,
but both are considered legacy as of Feb 2022.
The 2811:
The 1841:
we're going to need to understand the MODULES. What are these?
a few examples:
NM-1E is a 1-port ethernet module
NM-1FE-TX is a fast ethernet module
NM-8A/s is an Eight Port Async/Sync Network Module
HWIC-2T is a 2-port serial WAN interface card
HWIC-AP-AG-B is a wireless card
What is an "NM module"?
A network module is a software module that implements a specific
function in a network stack, such as a data link interface, a transport protocol,
or a network application.
What is a "HWIC module"?
A high-speed WAN interface card
Here is a look inside a real 2811:
Back to the requirements for our lab- Todd says the 2811 'Corp' router needs a switch module
and four serial interfaces. NOTE the book doesnt give specifics on how to create the topology in Packet Tracer.
Our Packet Tracer 2811 offers these modules:
The NM-ESW-16 appears to be the only 'switch module', so I will add that.
And the HWIC-2T is a 2-Port Serial High-Speed WAN Interface Card, providing 2 serial ports.
I will add two of these.
next: R3, which needs to be a 2811 with a wirless card. I will add the HWIC-AP-AG-B:
The HWIC-AP-AG-B module is a High-Speed WAN Interface Card providing integrated Access Point
functionality in the Cisco 1800 (Modular), Cisco 2800,
and Cisco 3800 Integrated Services Routers.
It supports Single Band 802.11b/g or Dual Band 802.11a/b/g radios.
our router hardware is in place:
and here is where we need to end up
Next we need to figure out how to connect the server farm to the switch card on R1:
if I use the auto-select cable, I get a copper crossover cable connecting at fa0/0 on the router.
Per the diagram fa0/0 should
connect to R3. I need to connect the servers to the switch card on R1.
Instead of using the auto-select cable, I'll try a straight-through cable.
Success. While the auto-select cable did not give me an option as to what port it will connect to, I did get the option when
manually applying the straight-through cable. Instead of connecting to F0/0 which would require a crossover-cable(computer to router),
I will connect to the integrated switch at port F1/0, then connect the other two servers to F1/1 and F1/2, respectively.
Also worth noting: the Physical Device diagrams in Packet Tracer do not show cables plugged into the ports.
We are relying on the labels on the logical diagram to see which cables are plugged into which ports...
As far as how we can tell what is connected from within the CLI.. I dont know right now.
Now I will connect the other routers. Here is the chart specifiying what interfaces should be used:
Router
Network Address
Interface
Address
CORP
10.1.1.0
Vlan1 (switch card)
10.1.1.1
10.1.2.0
S0/0/0
10.1.2.1
10.1.3.0
S0/0/1 (DCE)
10.1.3.1
10.1.4.0
S0/1/0
10.1.4.1
10.1.5.0
F0/0
10.1.5.1
R1
10.1.2.0
S0/0/0 (DCE)
10.1.2.2
10.1.3.0
S0/0/1
10.1.3.2
192.168.10.0
F0/0
192.168.10.1
192.168.20.0
F0/1
192.168.20.1
R2
10.1.4.0
S0/0/0 (DCE)
10.1.4.2
192.168.30.0
F0/0
192.168.30.1
192.168.40.0
F0/0
192.168.40.1
R3
10.1.5.0
F0/0
10.1.5.2
172.16.10.0
Dot11Radio0/0/0
172.16.10.1
PROBLEM
The R1 router doesnt appear to have any serial interfaces
I will add an HWIC-2T card to both R1 and R2 since the diagram calls for serial interfaces.
The HWIC-2T is a Cisco 2-Port Serial High-Speed WAN Interface Card, providing 2 serial ports.
PROBLEM
The Corp router is not showing the expected available interfaces. I need to connect R1 to the S0/0/0 interface on Corp and R2 to the S0/0/1 interface on Corp.
My Corp router is not showing those interfaces:
Solution
the placement of the cards on the router determines which interface numbers will be available.
In this case, it seems the interfaces start from the bottom right corner and increase on each slot moving clockwise. I found this out by filling all four slots on my router
which led to all interfaces being available. I then ran a card in each slot individually to isolate which interface numbers correspond to each slot:
Interestingly, while the physical slots seem to follow a 'clockwise' pattern, the list of available slots in the logical diagram does not;
We get an output of interfaces corresponding to slot 2, then 3, 1, and 4. This is a 'bottom to top' then 'left to right' pattern. Tricky.
Having said all that... I will run cards in slots 1 and 2 for this lab since we only need interfaces S0/0/0, S0/0/1, S0/1/0
The Router topology:
I'm not clear on the connections from R1 and R2 to the clients.. I assume there are switches involved.
For now I will follow the next steps in the book which
are to configure the corp router as follows:
Router(config)#
hostname Corp
Corp(config)#
enable secret todd
Corp(config)#
interface vlan 1
Corp(config-if)#
description Switch Card to Core Network
Corp(config-if)#
ip address 10.1.1.1 255.255.255.0
Corp(config-if)#
no shut
----------------------------------------------------------------------------------------------------------------
Corp(config-if)#
int f1/0
Corp(config-if)#
description Switch Port connection to WWW Server
Corp(config-if)#
no shutdown
Corp(config-if)#
int f1/1
Corp(config-if)#
description Switch Port connection to Email Server
Corp(config-if)#
no shutdown
Corp(config-if)#
int f1/2
Corp(config-if)#
description Switch Port connection to DNS Server
Corp(config-if)#
no shutdown
----------------------------------------------------------------------------------------------------------------
Corp(config-if)#
int s0/0/0
Corp(config-if)#
description 1st Connection to R1
Corp(config-if)#
ip address 10.1.2.1 255.255.255.0
Corp(config-if)#
no shut
Corp(config-if)#
int s0/0/1
Corp(config-if)#
description 2nd Connection to R1
Corp(config-if)#
ip address 10.1.3.1 255.255.255.0
Corp(config-if)#
no shut
Corp(config-if)#
int s0/1/0
Corp(config-if)#
description Connection to R2
Corp(config-if)#
ip address 10.1.4.1 255.255.255.0
Corp(config-if)#
no shut
Corp(config-if)#
int fa0/0
Corp(config-if)#
description Connection to R3
Corp(config-if)#
ip address 10.1.5.1 255.255.255.0
Corp(config-if)#
no shut
----------------------------------------------------------------------------------------------------------------
Corp(config-if)#
line con 0
Corp(config-if)#
password console
Corp(config-if)#
login
Corp(config-if)#
logging synchro
Corp(config-if)#
exec-timeout 0 0
----------------------------------------------------------------------------------------------------------------
Corp(config-if)#
line aux 0
Corp(config-if)#
password aux
Corp(config-if)#
login
Corp(config-if)#
exit
----------------------------------------------------------------------------------------------------------------
Corp(config)#
line vty ?
<1-15>Last Line number
Corp(config)#
line vty 0 15
Corp(config-if)#
password telnet
Corp(config-if)#
login
Corp(config-if)#
exit
----------------------------------------------------------------------------------------------------------------
Corp(config)#
no ip domain lookup
Corp(config)#
banner motd # This is my Corp 2811 ISR Router #
Ctrl + Z
%SYS-5-CONFIG_I: Configured from console by console
(Ctrl-Z: When in a config mode, ends the config mode and returns you to privileged EXEC mode.... same as typing exit(?))
Corp#
copy run start
Destination filename [startup-config]?
Building configuration...
[OK]
----------------------------------------------------------------------------------------------------------------
Corp#
show ip int br
Interface IP-Address OK? Method Status Protocol
FastEthernet0/0 10.1.5.1 YES manual up down
FastEthernet0/1 unassigned YES unset administratively down down
Serial0/0/0 10.1.2.1 YES manual down down
Serial0/0/1 10.1.3.1 YES manual down down
Serial0/1/0 10.1.4.1 YES manual down down
Serial0/1/1 unassigned YES unset administratively down down
FastEthernet1/0 unassigned YES unset up up
FastEthernet1/1 unassigned YES unset up up
FastEthernet1/2 unassigned YES unset up up
FastEthernet1/3 unassigned YES unset administratively down down
FastEthernet1/4 unassigned YES unset administratively down down
FastEthernet1/5 unassigned YES unset administratively down down
FastEthernet1/6 unassigned YES unset administratively down down
FastEthernet1/7 unassigned YES unset administratively down down
FastEthernet1/8 unassigned YES unset administratively down down
FastEthernet1/9 unassigned YES unset administratively down down
FastEthernet1/10 unassigned YES unset administratively down down
FastEthernet1/11 unassigned YES unset administratively down down
FastEthernet1/12 unassigned YES unset administratively down down
FastEthernet1/13 unassigned YES unset administratively down down
FastEthernet1/14 unassigned YES unset administratively down down
FastEthernet1/15 unassigned YES unset administratively down down
Vlan1 10.1.1.1 YES manual up up
----------------------------------------------------------------------------------------------------------------
Corp#
show run
Building configuration...
Current configuration : 2073 bytes
!
version 15.1
no service timestamps log datetime msec
no service timestamps debug datetime msec
no service password-encryption
!
hostname Corp
!
!
!
enable secret 5 $1$mERr$V5ujdIM9bTB/I.ipB0gkJ0
!
!
!
!
!
!
no ip cef
no ipv6 cef
!
!
!
!
license udi pid CISCO2811/K9 sn FTX1017U440-
!
!
!
!
!
!
!
!
!
no ip domain-lookup
!
!
spanning-tree mode pvst
!
!
!
!
!
!
interface FastEthernet0/0
description connection to R3
ip address 10.1.5.1 255.255.255.0
duplex auto
speed auto
!
interface FastEthernet0/1
no ip address
duplex auto
speed auto
shutdown
!
interface Serial0/0/0
description 1st connection to R1
ip address 10.1.2.1 255.255.255.0
clock rate 2000000
!
interface Serial0/0/1
description 2nd connection to R1
ip address 10.1.3.1 255.255.255.0
clock rate 2000000
!
interface Serial0/1/0
description connection to R2
ip address 10.1.4.1 255.255.255.0
!
interface Serial0/1/1
no ip address
clock rate 2000000
shutdown
!
interface FastEthernet1/0
description switch port connection to WWW Server
!
interface FastEthernet1/1
description switch port connection to Email Server
!
interface FastEthernet1/2
description switch port connection to DNS Server
!
interface FastEthernet1/3
shutdown
!
interface FastEthernet1/4
shutdown
!
interface FastEthernet1/5
shutdown
!
interface FastEthernet1/6
shutdown
!
interface FastEthernet1/7
shutdown
!
interface FastEthernet1/8
shutdown
!
interface FastEthernet1/9
shutdown
!
interface FastEthernet1/10
shutdown
!
interface FastEthernet1/11
shutdown
!
interface FastEthernet1/12
shutdown
!
interface FastEthernet1/13
shutdown
!
interface FastEthernet1/14
shutdown
!
interface FastEthernet1/15
shutdown
!
interface Vlan1
description Switch Card to Core Network
ip address 10.1.1.1 255.255.255.0
!
ip classless
!
ip flow-export version 9
!
!
!
banner motd ^C This is my Corp 2811 ISR Router ^C
!
!
!
!
!
line con 0
exec-timeout 0 0
password console
logging synchronous
login
!
line aux 0
password aux
login
!
line vty 0 4
password telnet
login
line vty 5 15
password telnet
login
!
!
!
end
-----------------------------------------------------------------------------------------------------------------------
more configurations:
R1
Router(config)#
hostname R1
R1(config)#
enable secret todd
R1(config)#
int s0/0/0
R1(config-if)#
ip address 10.1.2.2 255.255.255.0
R1(config-if)#
Decription 1st connection to corp router
R1(config-if)#
no shut
-----------------------------------------------------------------------------------------------
R1(config-if)#
int s0/0/1
R1(config-if)#
ip address 10.1.3.2 255.255.255.0
R1(config-if)#
Decription 2nd connection to corp router
R1(config-if)#
no shut
-----------------------------------------------------------------------------------------------
R1(config-if)#
int f0/0
R1(config-if)#
ip address 192.168.10.1 255.255.255.0
R1(config-if)#
Decription connection to finance
R1(config-if)#
no shut
-----------------------------------------------------------------------------------------------
R1(config-if)#
int f0/1
R1(config-if)#
ip address 192.168.20.1 255.255.255.0
R1(config-if)#
Decription connection to marketing
R1(config-if)#
no shut
R1(config-if)#
exit
-----------------------------------------------------------------------------------------------
R1(config)#
line con 0
R1(config-line)#
password console
R1(config-line)#
login
R1(config-line)#
logging synchronous
R1(config-line)#
exec-timeout 0 0
-----------------------------------------------------------------------------------------------
R1(config-line)#
line aux 0
R1(config-line)#
password aux
R1(config-line)#
login
R1(config-line)#
exit
-----------------------------------------------------------------------------------------------
R1(config)#
line vty 0 ?
<0-15> Last Line number
R1(config)#
line vty 0 807
R1(config-line)#
password telnet
R1(config-line)#
login
R1(config-line)#
banner motd # This is my R1 Router #
R1(config-line)#
exit
-----------------------------------------------------------------------------------------------
R1(config)#
no ip domain-lookup
R1(config)#
exit
R1#
copy run start
R2
Router(config)#
hostname R2
R2(config)#
enable secret todd
R2(config)#
int s0/0/0
R2(config-if)#
ip address 10.1.4.2 255.255.255.0
R2(config-if)#
description connection to corp router
R2(config-if)#
no shut
-----------------------------------------------------------------------------------------------
R2(config-if)#
int f0/0
R2(config-if)#
ip address 192.168.30.1 255.255.255.0
R2(config-if)#
description connection to sales PC
R2(config-if)#
no shut
-----------------------------------------------------------------------------------------------
R2(config-if)#
int f0/1
R2(config-if)#
ip address 192.168.40.1 255.255.255.0
R2(config-if)#
description connection to HR pc
R2(config-if)#
no shut
-----------------------------------------------------------------------------------------------
R2(config-if)#
line con 0
R2(config-line)#
password console
R2(config-line)#
login
R2(config-line)#
logging synchronous
R2(config-line)#
exec-timeout 0 0
-----------------------------------------------------------------------------------------------
R2(config-line)#
line aux 0
R2(config-line)#
password aux
R2(config-line)#
login
R2(config-line)#
exit
-----------------------------------------------------------------------------------------------
R2(config)#
line vty 0 ?
<0-15> Last Line number
R2(config)#
line vty 0 807
R2(config-line)#
password telnet
R2(config-line)#
login
R2(config-line)#
banner motd # This is my R1 Router #
R2(config-line)#
exit
-----------------------------------------------------------------------------------------------
R2(config)#
no ip domain-lookup
R2(config)#
exit
R2#
copy run start
R3
Router(config)#
hostname R3
R3(config)#
enable secret todd
R3(config)#
int f0/0
R3(config-if)#
ip address 10.1.5.2 255.255.255.0
R3(config-if)#
description connection to corp router
R3(config-if)#
no shut
-----------------------------------------------------------------------------------------------
R3(config-if)#
int dot11radio0/0/0
R3(config-if)#
ip address 172.16.10.1 255.255.255.0
R3(config-if)#
description WLAN for mobile user
R3(config-if)#
no shut
R3(config-if)#
ssid ADMIN
stuck here 2-5-22-- packet tracer isnt taking me into the config-if-ssid prompt
R3(config-if-ssid)#
guest-mode
R3(config-if-ssid)#
authentication open
R3(config-if-ssid)#
ingrastructure-ssid
R3(config-if-ssid)#
exit
-----------------------------------------------------------------------------------------------
R3(config-if)#
line con 0
R3(config-line)#
password console
R3(config-line)#
login
R3(config-line)#
logging synchronous
R3(config-line)#
exec-timeout 0 0
-----------------------------------------------------------------------------------------------
R3(config-line)#
line aux 0
R3(config-line)#
password aux
R3(config-line)#
login
R3(config-line)#
exit
-----------------------------------------------------------------------------------------------
R3(config)#
line vty 0 ?
<0-15> Last Line number
R3(config)#
line vty 0 807
R3(config-line)#
password telnet
R3(config-line)#
login
R3(config-line)#
banner motd # This is my R1 Router #
R3(config-line)#
exit
-----------------------------------------------------------------------------------------------
R3(config)#
no ip domain-lookup
R3(config)#
exit
R3#
copy run start
PROBLEM
i cant get into conf-if-ssid prompt
R3(config-if)#
ssid ADMIN
%LINK-5-CHANGED: Interface Dot11Radio0/0/0, changed state to administratively down
%LINEPROTO-5-UPDOWN: Line protocol on Interface Dot11Radio0/0/0, changed state to down
%LINK-5-CHANGED: Interface Dot11Radio0/0/0, changed state to up
%LINEPROTO-5-UPDOWN: Line protocol on Interface Dot11Radio0/0/0, changed state to up
R3(config-if)#
research led me to this thread, which is a dead end:
further research led me here:
R3(config)# global config mode
R3(config)#
dot11 ssid ADMIN
creates an SSID or lets you config an existing SSID
R3(config-ssid)#
guest-mode
R3(config-ssid)#
%LINK-5-CHANGED: Interface Dot11Radio0/0/0, changed state to administratively down
%LINEPROTO-5-UPDOWN: Line protocol on Interface Dot11Radio0/0/0, changed state to down
%LINK-5-CHANGED: Interface Dot11Radio0/0/0, changed state to up
%LINEPROTO-5-UPDOWN: Line protocol on Interface Dot11Radio0/0/0, changed state to up
R3(config-ssid)#
authentication open
R3(config-ssid)#
%LINK-5-CHANGED: Interface Dot11Radio0/0/0, changed state to administratively down
%LINEPROTO-5-UPDOWN: Line protocol on Interface Dot11Radio0/0/0, changed state to down
%LINK-5-CHANGED: Interface Dot11Radio0/0/0, changed state to up
%LINEPROTO-5-UPDOWN: Line protocol on Interface Dot11Radio0/0/0, changed state to up
R3(config-ssid)#
infrastructure-ssid
R3(config-ssid)#infrastructure-ssid
^
% Invalid input detected at '^' marker.
this command given by the book doesnt appear to be valid
R3(config-ssid)#
?
authentication authentication method
exit Exit from ssid sub mode
guest-mode guest ssid
no Negate a command or set it's defaults
wpa-psk Configure Wi-Fi Protected Access pre-shared key
back into the interface to see what the options are
R3(config-ssid)#
int dot110/0/0
R3(config-if)#
?
arp Set arp type (arpa, probe, snap) or timeout or log options
bandwidth Set bandwidth informational parameter
cdp CDP interface subcommands
crypto Encryption/Decryption commands
delay Specify interface throughput delay
description Interface specific description
encryption Configure dot11 encryption parameters
exit Exit from interface configuration mode
fair-queue Enable Fair Queuing on an Interface
hold-queue Set hold queue depth
ip Interface Internet Protocol config commands
mac-address Manually set interface MAC address
mtu Set the interface Maximum Transmission Unit (MTU)
no Negate a command or set its defaults
priority-group Assign a priority group to an interface
service-policy Configure QoS Service Policy
shutdown Shutdown the selected interface
speed Set allowed radio bit rates
ssid Configure radio service set parameters
tx-ring-limit Configure PA level transmit ring limit
i'll consider the problem *mostly* solved. I was able to assign the SSD.
The infrastructure command may be expendable in this case... to be determined
here is our configuration for R3
R3#
show run
Building configuration...
Current configuration : 1682 bytes
!
version 15.1
no service timestamps log datetime msec
no service timestamps debug datetime msec
no service password-encryption
!
hostname R3
!
!
!
enable secret 5 $1$mERr$V5ujdIM9bTB/I.ipB0gkJ0
!
!
ip dhcp excluded-address 172.16.10.1 172.16.10.10
!
ip dhcp pool Admin
network 172.16.10.0 255.255.255.0
default-router 172.16.10.1
!
dot11 ssid ADMIN
authentication open
guest-mode
!
dot11 ssid ADMIN2
authentication open
guest-mode
!
!
!
ip cef
no ipv6 cef
!
!
!
!
license udi pid CISCO2811/K9 sn FTX1017RE40-
!
!
!
!
!
!
!
!
!
no ip domain-lookup
ip name-server 172.16.10.4
!
!
spanning-tree mode pvst
!
!
!
!
!
!
interface FastEthernet0/0
description connection to corp router
ip address 10.1.5.2 255.255.255.0
duplex auto
speed auto
!
interface FastEthernet0/1
no ip address
duplex auto
speed auto
shutdown
!
interface Dot11Radio0/0/0
description WAN for mobile
ip address 172.16.10.1 255.255.255.0
speed 12.0 18.0 24.0 36.0 48.0 54.0 6.0 9.0 basic-1.0 basic-11.0 basic-2.0 basic-5.5
ssid ADMIN2
!
interface Dot11Radio0/0/1
no ip address
speed 18.0 36.0 48.0 54.0 9.0 basic-12.0 basic-24.0 basic-6.0
!
interface Serial0/1/0
no ip address
clock rate 2000000
!
interface Serial0/1/1
no ip address
clock rate 2000000
!
interface Vlan1
no ip address
shutdown
!
router rip
version 2
network 10.0.0.0
network 172.16.0.0
!
ip classless
ip route 0.0.0.0 0.0.0.0 10.1.5.1
!
ip flow-export version 9
!
!
!
banner motd ^C this is R3 $
this is R3 ^C
!
!
!
!
!
line con 0
exec-timeout 0 0
password console
logging synchronous
login
!
line aux 0
password aux
login
!
line vty 0 4
password telnet
login
line vty 5 15
password telnet
login
!
!
!
end
to summarize...
the book is a little off here.
-----------------------------------------------------------------------------------------------
R3(config-if)#
int dot11radio0/0/0
R3(config-if)#
ip address 172.16.10.1 255.255.255.0
R3(config-if)#
description WLAN for mobile user
R3(config-if)#
no shut
at this point we have created a wireless interface with an IP address but no SSID exists on this router
interface Dot11Radio0/0/0
description test router 2
ip address 172.16.10.1 255.255.255.0
speed 12.0 18.0 24.0 36.0 48.0 54.0 6.0 9.0 basic-1.0 basic-11.0 basic-2.0 basic-5.5
Trying to use the command "ssid ADMIN" doesnt work here. The below commands are invalid here:
R3(config-if)#
ssid ADMIN
R3(config-if-ssid)#
guest-mode
R3(config-if-ssid)#
authentication open
R3(config-if-ssid)#
ingrastructure-ssid
R3(config-if-ssid)#
exit
-----------------------------------------------------------------------------------------------
We need to drop out of config-if, back to config, and enter SSID config mode
-----------------------------------------------------------------------------------------------
R3(config-if)#
exit
R3(config)#
dot11 ssid ADMIN2 creates an ssid named ADMIN2, and puts us into SSID config mode
R3(config-ssid)#
guest-mode
R3(config-ssid)#
authentication open
then out of config-ssid and back to interface config
R3(config-ssid)#
exit
R3(config)
int dot11r0/0/0
R3(config-if)
?
arp Set arp type (arpa, probe, snap) or timeout or log options
bandwidth Set bandwidth informational parameter
cdp CDP interface subcommands
crypto Encryption/Decryption commands
delay Specify interface throughput delay
description Interface specific description
encryption Configure dot11 encryption parameters
exit Exit from interface configuration mode
fair-queue Enable Fair Queuing on an Interface
hold-queue Set hold queue depth
ip Interface Internet Protocol config commands
mac-address Manually set interface MAC address
mtu Set the interface Maximum Transmission Unit (MTU)
no Negate a command or set its defaults
priority-group Assign a priority group to an interface
service-policy Configure QoS Service Policy
shutdown Shutdown the selected interface
speed Set allowed radio bit rates
ssid Configure radio service set parameters
tx-ring-limit Configure PA level transmit ring limit
we have the option for ssid
R3(config-if)
ssid ADMIN2
%LINK-5-CHANGED: Interface Dot11Radio0/0/0, changed state to administratively down
%LINEPROTO-5-UPDOWN: Line protocol on Interface Dot11Radio0/0/0, changed state to down
%LINK-5-CHANGED: Interface Dot11Radio0/0/0, changed state to up
%LINEPROTO-5-UPDOWN: Line protocol on Interface Dot11Radio0/0/0, changed state to up
the router resets the interface..
-----------------------------------------------------------------------------------------------
R3(config-if)
do show run
[cut]
!
!
dot11 ssid ADMIN2
authentication open
guest-mode
!
!
[cut]
!
interface Dot11Radio0/0/0
description test router 2
ip address 172.16.10.1 255.255.255.0
speed 12.0 18.0 24.0 36.0 48.0 54.0 6.0 9.0 basic-1.0 basic-11.0 basic-2.0 basic-5.5
ssid ADMIN2
!
[cut]
the SSID is created and assigned to the interface
To summarize.
Wrong: create the dot11 interface, then create the SSID from CONFIG-IF mode, which puts you into CONFIG-IF-SSID (there is no such mode on this router) mode, then modify the ssid from there...
Correct: create the dot11 interface. Exit CONFIG-IF and go back to GLOBAL CONFIG. Create the SSID which puts you in CONFIG-SSID mode.
Configure the ssid. Then exit CONFIG-SSID. Back into CONFIG-IF, assign the SSID
We have one more task for R3- Configuring the DHCP pool for wireless clients.
R3(config)#
ip dhcp pool Admin creating the pool name as "Admin"
R3(dhcp-config)#
network 172.16.10.0 255.255.255.0
R3(dhcp-config)#
default-router 172.16.10.1 aka default-gateway for clients in the pool
R3(dhcp-config)#
ip name-server 172.16.10.4 dns server
*automatically exits dhcp-config prompt*
R3(config)#
ip dhcp excluded-address 172.16.10.1 172.16.10.10 excludes the range given
172.16.10.1 is the router interface- we need to specifically exclude it from the pool
this setup should allow the wireless client to pick up an IP after connecting to the open SSID.
However, I was having trouble at first-
even though I seemed to have the SSID set correctly, i was hitting a WEP password prompt
i didnt see any obvious issues with the wifi module im using on the laptop:
The Linksys-WPC300N module provides one 2.4GHz wireless interface suitable for connection to wireless networks.
The module supports protocols that use Ethernet for LAN access.
I ended up creating a new SSID, with the same settings as the original:
R3(config)#
dot11 ssid ADMIN2
R3(config-ssid)#
guest-mode
R3(config-ssid)#
authentication open
and then I assigned the ip address to ssid ADMIN2 instead of the orginal ADMIN ssid
R3(config)#
int dot110/0/0
R3(config-if)#
ip address 172.16.10.1 255.255.255.0
R3(config-if)#
description WLAN for mobile user
R3(config-if)#
no shut
R3(config-if)#
ssid ADMIN2
R3#
show run
Building configuration...
Current configuration : 1467 bytes
!
version 15.1
no service timestamps log datetime msec
no service timestamps debug datetime msec
no service password-encryption
!
hostname R3
!
!
!
enable secret 5 $1$mERr$V5ujdIM9bTB/I.ipB0gkJ0
!
!
ip dhcp excluded-address 172.16.10.1 172.16.10.10
!
ip dhcp pool Admin
network 172.16.10.0 255.255.255.0
default-router 172.16.10.1
!
dot11 ssid ADMIN
authentication open
guest-mode
!
dot11 ssid ADMIN2
authentication open
guest-mode
!
!
!
ip cef
no ipv6 cef
!
!
!
!
license udi pid CISCO2811/K9 sn FTX1017RE40-
!
!
!
!
!
!
!
!
!
no ip domain-lookup
ip name-server 172.16.10.4
!
!
spanning-tree mode pvst
!
!
!
!
!
!
interface FastEthernet0/0
description connection to corp router
ip address 10.1.5.2 255.255.255.0
duplex auto
speed auto
!
interface FastEthernet0/1
no ip address
duplex auto
speed auto
shutdown
!
interface Dot11Radio0/0/0
description WAN for mobile
ip address 172.16.10.1 255.255.255.0
speed 12.0 18.0 24.0 36.0 48.0 54.0 6.0 9.0 basic-1.0 basic-11.0 basic-2.0 basic-5.5
ssid ADMIN2
!
interface Dot11Radio0/0/1
no ip address
speed 18.0 36.0 48.0 54.0 9.0 basic-12.0 basic-24.0 basic-6.0
!
interface Vlan1
no ip address
shutdown
!
ip classless
!
ip flow-export version 9
!
!
!
banner motd ^C this is R3 $
this is R3 ^C
!
!
!
!
!
line con 0
exec-timeout 0 0
password console
logging synchronous
login
!
line aux 0
password aux
login
!
line vty 0 4
password telnet
login
line vty 5 15
password telnet
login
!
!
!
end
Recall the DHCP configuration on R3:
R3(config)#
ip dhcp pool Admin creating the pool name as "Admin"
R3(dhcp-config)#
network 172.16.10.0 255.255.255.0
R3(dhcp-config)#
default-router 172.16.10.1 aka default-gateway for clients in the pool
R3(dhcp-config)#
ip name-server 172.16.10.4 dns server
*automatically exits dhcp-config prompt*
R3(config)#
ip dhcp excluded-address 172.16.10.1 172.16.10.10 excludes the range given
172.16.10.1 is the router interface- we need to specifically exclude it from the pool
we can check the configuration:
R3#
show ip dhcp pool
Pool Admin :
Utilization mark (high/low) : 100 / 0
Subnet size (first/next) : 0 / 0
Total addresses : 254
Leased addresses : 1
Excluded addresses : 1
Pending event : none
1 subnet is currently in the pool
Current index IP address range Leased/Excluded/Total
172.16.10.1 172.16.10.1 - 172.16.10.254 1 / 1 / 254
R3#
show ip dhcp binding
IP address Client-ID/ Lease expiration Type
Hardware address
172.16.10.11 00D0.979A.733B -- Automatic
the show command is becoming more familiar
R3#
show ip?
access-lists List access lists
arp IP ARP table
bgp BGP information
cache IP fast-switching route cache
cef Cisco Express Forwarding
dhcp Show items in the DHCP database
eigrp IP-EIGRP show commands
inspect CBAC (Context Based Access Control) information
interface IP interface status and configuration
ips IPS (Intrusion Prevention System) information
nat IP NAT information
nbar Network-Based Application Recognition
ospf OSPF information
protocols IP routing protocol process parameters and statistics
rip IP RIP show commands
route IP routing table
ssh Information on SSH
we'll use show ip route soon on all the routers. For now, here is the output for R3:
R3#
show ip route
Codes: L - local, C - connected, S - static, R - RIP, M - mobile, B - BGP
D - EIGRP, EX - EIGRP external, O - OSPF, IA - OSPF inter area
N1 - OSPF NSSA external type 1, N2 - OSPF NSSA external type 2
E1 - OSPF external type 1, E2 - OSPF external type 2, E - EGP
i - IS-IS, L1 - IS-IS level-1, L2 - IS-IS level-2, ia - IS-IS inter area
* - candidate default, U - per-user static route, o - ODR
P - periodic downloaded static route
Gateway of last resort is not set
10.0.0.0/8 is variably subnetted, 2 subnets, 2 masks
C 10.1.5.0/24 is directly connected, FastEthernet0/0
L 10.1.5.2/32 is directly connected, FastEthernet0/0
172.16.0.0/16 is variably subnetted, 2 subnets, 2 masks
C 172.16.10.0/24 is directly connected, Dot11Radio0/0/0
L 172.16.10.1/32 is directly connected, Dot11Radio0/0/0
Before moving on to the routing configurations, here is a review of the topology
I have switched over to the DrawIO diagram app to lay out the topology.
The Packet Tracer diagram becomes
too crowded to see the labels; it's labeling system forces awkward positioning of the objects; the interface
label's cant be moved, so if objects are too close together their labels cover eachother.. not good.
DrawIO allows a cleaner layout with plenty of room to label interfaces and ip addresses.
As a compromise, I'll use both.
I have the packet tracer objects spread out just enough to see the interfaces
and the label for each router. From here I can jump into the CLI for each device.
The DrawIO diagram allows me to cleary see IP addresses
I want to also review all of the configurations we just performed:
PROBLEM
The book specifies that of the two serial conections between R1 and Corp, there should be a DCE on each end..
Both of my DCE's are on the same end.
First lets be sure we understand what DCE means:
networkengineering.stackexchange.com/
One side of the link (DCE), has to transmit the clock signal, which controls the data rate, and the other side (DTE) receives the clock signal.
That is good enough for now. Note that while the book does specify in the diagram that each side should have a DCE, it was not actually mentioned in the configs.
We did not set a DCE or clock rate when conifguring those interfaces.
To fix this in my Packet Tracer topology, I did some quick research:
While this post wasnt pertaining to Packet Tracer, it got me thinking about the cable itself.
I deleted both of my existing serial connections and looked at the options for creating a new cable.
I noticed one is a DCE and one is a DTE:
Fixed the issue
back to the configuration overview: 4 routers, abbreviated show run output
Corp
interface FastEthernet0/0
description connection to R3
ip address 10.1.5.1 255.255.255.0
duplex auto
speed auto
!
interface FastEthernet0/1
no ip address
duplex auto
speed auto
shutdown
!
interface Serial0/0/0
description 1st connection to R1
ip address 10.1.2.1 255.255.255.0
!
interface Serial0/0/1
description 2nd connection to R1
ip address 10.1.3.1 255.255.255.0
clock rate 2000000
!
interface Serial0/1/0
description connection to R2
ip address 10.1.4.1 255.255.255.0
!
interface Vlan1
description Switch Card to Core Network
ip address 10.1.1.1 255.255.255.0
!
interface FastEthernet1/0
description switch port connection to WWW Server
switchport mode access
switchport nonegotiate
!
interface FastEthernet1/1
description switch port connection to Email Server
switchport mode access
switchport nonegotiate
!
interface FastEthernet1/2
description switch port connection to DNS Server
switchport mode access
switchport nonegotiate
!
R1
interface FastEthernet0/0
description connection to Finance
ip address 192.168.10.1 255.255.255.0
duplex auto
speed auto
!
interface FastEthernet0/1
description connection to Marketing
ip address 192.168.20.1 255.255.255.0
duplex auto
speed auto
!
interface Serial0/0/0
description 1st connection to Corp router
ip address 10.1.2.2 255.255.255.0
clock rate 2000000
!
interface Serial0/0/1
description 2nd connecction to Corp router
ip address 10.1.3.2 255.255.255.0
!
R2
interface FastEthernet0/0
description Connection to Sales PC
ip address 192.168.30.1 255.255.255.0
duplex auto
speed auto
!
interface FastEthernet0/1
description Connection to HR PC
ip address 192.168.40.1 255.255.255.0
duplex auto
speed auto
!
interface Serial0/0/0
description Connection to Corp Router
ip address 10.1.4.2 255.255.255.0
clock rate 2000000
!
interface Serial0/0/1
no ip address
clock rate 2000000
shutdown
!
R3
interface FastEthernet0/0
description connection to corp router
ip address 10.1.5.2 255.255.255.0
duplex auto
speed auto
!
interface FastEthernet0/1
no ip address
duplex auto
speed auto
shutdown
!
interface Dot11Radio0/0/0
description WAN for mobile
ip address 172.16.10.1 255.255.255.0
speed 12.0 18.0 24.0 36.0 48.0 54.0 6.0 9.0 basic-1.0 basic-11.0 basic-2.0 basic-5.5
ssid ADMIN2
and here is the output of show ip route for each router
Codes: C - connected, S - static, I - IGRP, R - RIP, M - mobile, B - BGP
D - EIGRP, EX - EIGRP external, O - OSPF, IA - OSPF inter area
N1 - OSPF NSSA external type 1, N2 - OSPF NSSA external type 2
E1 - OSPF external type 1, E2 - OSPF external type 2, E - EGP
i - IS-IS, L1 - IS-IS level-1, L2 - IS-IS level-2, ia - IS-IS inter area
* - candidate default, U - per-user static route, o - ODR
P - periodic downloaded static route
Gateway of last resort is not set
Corp
10.0.0.0/24 is subnetted, 2 subnets
C 10.1.2.0 is directly connected, Serial0/0/0
C 10.1.3.0 is directly connected, Serial0/0/1
C 192.168.10.0/24 is directly connected, FastEthernet0/0
C 192.168.20.0/24 is directly connected, FastEthernet0/1
R1
10.0.0.0/24 is subnetted, 2 subnets
C 10.1.2.0 is directly connected, Serial0/0/0
C 10.1.3.0 is directly connected, Serial0/0/1
C 192.168.10.0/24 is directly connected, FastEthernet0/0
C 192.168.20.0/24 is directly connected, FastEthernet0/1
R2
10.0.0.0/24 is subnetted, 1 subnets
C 10.1.4.0 is directly connected, Serial0/0/0
C 192.168.30.0/24 is directly connected, FastEthernet0/0
C 192.168.40.0/24 is directly connected, FastEthernet0/1
R3
10.0.0.0/8 is variably subnetted, 2 subnets, 2 masks
C 10.1.5.0/24 is directly connected, FastEthernet0/0
L 10.1.5.2/32 is directly connected, FastEthernet0/0
172.16.0.0/16 is variably subnetted, 2 subnets, 2 masks
C 172.16.10.0/24 is directly connected, Dot11Radio0/0/0
L 172.16.10.1/32 is directly connected, Dot11Radio0/0/0
Note that this is before we have configured any 'routing'. We are seeing configured, directly connected networks.
The output for R3 is particularly interesting
What does 'variably' subnetted mean, and what is the "L" next to these routes. And why do they have a mask of 32?
R3
10.0.0.0/8 is variably subnetted, 2 subnets, 2 masks
C 10.1.5.0/24 is directly connected, FastEthernet0/0
L 10.1.5.2/32 is directly connected, FastEthernet0/0
172.16.0.0/16 is variably subnetted, 2 subnets, 2 masks
C 172.16.10.0/24 is directly connected, Dot11Radio0/0/0
L 172.16.10.1/32 is directly connected, Dot11Radio0/0/0
Cisco forums
That makes sense, but my question is why did the other routing tables not behave the same way? R3 is the only one that shows "L" routes.
The book tells us we're using two different model routers, and indeed they are running different IOS versions:
NOTE that at the time the book was published IOS 15 was not released yet, so the book assumes all routers are running 12.4
But that still doesnt explain why Corp and R3 are behaving differently..
Corp
10.0.0.0/24 is subnetted, 2 subnets
C 10.1.2.0 is directly connected, Serial0/0/0
C 10.1.3.0 is directly connected, Serial0/0/1
C 192.168.10.0/24 is directly connected, FastEthernet0/0
C 192.168.20.0/24 is directly connected, FastEthernet0/1
R1
10.0.0.0/24 is subnetted, 2 subnets
C 10.1.2.0 is directly connected, Serial0/0/0
C 10.1.3.0 is directly connected, Serial0/0/1
C 192.168.10.0/24 is directly connected, FastEthernet0/0
C 192.168.20.0/24 is directly connected, FastEthernet0/1
R2
10.0.0.0/24 is subnetted, 1 subnets
C 10.1.4.0 is directly connected, Serial0/0/0
C 192.168.30.0/24 is directly connected, FastEthernet0/0
C 192.168.40.0/24 is directly connected, FastEthernet0/1
R3
10.0.0.0/8 is variably subnetted, 2 subnets, 2 masks
C 10.1.5.0/24 is directly connected, FastEthernet0/0
L 10.1.5.2/32 is directly connected, FastEthernet0/0
172.16.0.0/16 is variably subnetted, 2 subnets, 2 masks
C 172.16.10.0/24 is directly connected, Dot11Radio0/0/0
L 172.16.10.1/32 is directly connected, Dot11Radio0/0/0
how are Corp and R3 different?
The answer is, they are not...
I have accidentally displayed the R1 output to the Corp windows. Error in translating data from the IOS to this webpage..
here's the corrected output.
Corp
10.0.0.0/8 is variably subnetted, 10 subnets, 2 masks
C 10.1.1.0/24 is directly connected, Vlan1
L 10.1.1.1/32 is directly connected, Vlan1
C 10.1.2.0/24 is directly connected, Serial0/0/0
L 10.1.2.1/32 is directly connected, Serial0/0/0
C 10.1.3.0/24 is directly connected, Serial0/0/1
L 10.1.3.1/32 is directly connected, Serial0/0/1
C 10.1.4.0/24 is directly connected, Serial0/1/0
L 10.1.4.1/32 is directly connected, Serial0/1/0
C 10.1.5.0/24 is directly connected, FastEthernet0/0
L 10.1.5.1/32 is directly connected, FastEthernet0/0
R1
10.0.0.0/24 is subnetted, 2 subnets
C 10.1.2.0 is directly connected, Serial0/0/0
C 10.1.3.0 is directly connected, Serial0/0/1
C 192.168.10.0/24 is directly connected, FastEthernet0/0
C 192.168.20.0/24 is directly connected, FastEthernet0/1
R2
10.0.0.0/24 is subnetted, 1 subnets
C 10.1.4.0 is directly connected, Serial0/0/0
C 192.168.30.0/24 is directly connected, FastEthernet0/0
C 192.168.40.0/24 is directly connected, FastEthernet0/1
R3
10.0.0.0/8 is variably subnetted, 2 subnets, 2 masks
C 10.1.5.0/24 is directly connected, FastEthernet0/0
L 10.1.5.2/32 is directly connected, FastEthernet0/0
172.16.0.0/16 is variably subnetted, 2 subnets, 2 masks
C 172.16.10.0/24 is directly connected, Dot11Radio0/0/0
L 172.16.10.1/32 is directly connected, Dot11Radio0/0/0
We do indeed see consistent behavior differences between IOS versions 12.4 and 15.1
recap Corp and R3 outputs:
update topology with Router versions
That covers the first half of Chapter 8. Now we are ready to configure IP routing on our network.
There are three ways: Static, Default, Dynamic
To set up static routes, we simply need to program the routes using the ip route command
Syntax
ip route
[
destination network
]
[
mask
]
[
next hop
]
[
exitinterface
]
[
administrative distance
]
[
permanent
]
destination network and mask
the network data we're adding to the routing table
next-hop address
the address of the next-hop router that will receive the packet and forward to the remote network.
This is the IP address of a router interface that is directly connected.
It must be pingable.
exit interface
can be used instead of next hop address
administrative distance
by default, static routes have an admin distance of 1 if you use a next hop, or 0 if you use exit interface.
You can change the value by adding an administrative weight at the end of the command. More on this later with dynamic routing.
permanent
if the interface is shut down or the router cant communicate to the next hp router, the route will automatically be discarded from the table by default.
The 'permanent' option keeps the entry in the routing table indefenitely.
-----------------------------------------------------------------------------------------------------
Corp has automatically picked up 5 routes that are directly connected:
10.1.1.0 to corp switch card
10.1.2.0 to R1
10.1.3.0 to R1
10.1.4.0 to R2
10.1.5.0 to R3
We need to program 5 more routes:
192.168.10.0 traverse R1
192.168.20.0 traverse R1
192.168.30.0 traverse R1
192.168.40.0 traverse R2
172.16.10.0 traverse R3
-----------------------------------------------------------------------------------------------------
R1 has automatically picked up 4 routes that are directly connected:
10.1.2.0
10.1.3.0
192.168.10.0
192.168.20.0
We need to program 6 more routes:
10.1.1.0
10.1.4.0
10.1.5.0
192.168.30.0
192.168.40.0
172.16.10.0
-----------------------------------------------------------------------------------------------------
R2 has automatically picked up 3 routes that are directly connected:
10.1.4.0
192.168.30.0
192.168.40.0
We need to program 7 more routes:
10.1.1.0
10.1.2.0
10.1.3.0
10.1.5.0
192.168.10.0
192.168.20.0
172.16.10.0
-----------------------------------------------------------------------------------------------------
R3 has automatically picked up 2 routes that are directly connected:
10.1.5.0
172.16.10.0
We need to program 8 more routes:
10.1.1.0
10.1.2.0
10.1.3.0
10.1.4.0
192.168.10.0
192.168.20.0
192.168.30.0
192.168.40.0
Notice the pattern- each router ends up with 10 routes
There are 10 routes total in this topology. AKA ten broadcast domains
Programming the routes
Corp
Corp(config)#
ip route 192.168.10.0 255.255.255.0 10.1.2.2 150
Corp(config)#
ip route 192.168.20.0 255.255.255.0 10.1.3.2 150
Corp(config)#
ip route 192.168.30.0 255.255.255.0 10.1.4.2 150
Corp(config)#
ip route 192.168.40.0 255.255.255.0 10.1.4.2 150
Corp(config)#
ip route 172.16.10.0 255.255.255.0 10.1.5.2 150
Corp(config)#
do show ip route
In the first line, the router is saying that a
classful A network is being subnetted
There are 5 routes directly connected
We see two lines per route (one for the network and one
for the interface(/32)-
10.0.0.0/8 is variably subnetted, 10 subnets, 2 masks
C 10.1.1.0/24 is directly connected, Vlan1
L 10.1.1.1/32 is directly connected, Vlan1
C 10.1.2.0/24 is directly connected, Serial0/0/0
L 10.1.2.1/32 is directly connected, Serial0/0/0
C 10.1.3.0/24 is directly connected, Serial0/0/1
L 10.1.3.1/32 is directly connected, Serial0/0/1
C 10.1.4.0/24 is directly connected, Serial0/1/0
L 10.1.4.1/32 is directly connected, Serial0/1/0
C 10.1.5.0/24 is directly connected, FastEthernet0/0
L 10.1.5.1/32 is directly connected, FastEthernet0/0
and 5 routes that require traversal of a router to reach
172.16.0.0/24 is subnetted, 1 subnets
S 172.16.10.0/24 [150/0] via 10.1.5.2
S 192.168.10.0/24 [150/0] via 10.1.2.2
S 192.168.20.0/24 [150/0] via 10.1.3.2
S 192.168.30.0/24 [150/0] via 10.1.4.2
S 192.168.40.0/24 [150/0] via 10.1.4.2
R1
R1(config)#
ip route 10.1.1.0 255.255.255.0 10.1.2.1 150
R1(config)#
ip route 10.1.4.0 255.255.255.0 10.1.3.1 150
R1(config)#
ip route 10.1.5.0 255.255.255.0 10.1.2.1 150
R1(config)#
ip route 192.168.30.0 255.255.255.0 10.1.3.1 150
R1(config)#
ip route 192.168.40.0 255.255.255.0 10.1.2.1 150
R1(config)#
ip route 172.16.10.0 255.255.255.0 10.1.3.1 150
the only way to get across the corp router is to go into it via 10.1.2.1 or 10.1.3.1
R1(config)#
do show ip route
10.0.0.0/24 is subnetted, 5 subnets
S 10.1.1.0 [150/0] via 10.1.2.1
C 10.1.2.0 is directly connected, Serial0/0/0
C 10.1.3.0 is directly connected, Serial0/0/1
S 10.1.4.0 [150/0] via 10.1.3.1
S 10.1.5.0 [150/0] via 10.1.2.1
172.16.0.0/24 is subnetted, 1 subnets
S 172.16.10.0 [150/0] via 10.1.3.1
C 192.168.10.0/24 is directly connected, FastEthernet0/0
C 192.168.20.0/24 is directly connected, FastEthernet0/1
S 192.168.30.0/24 [150/0] via 10.1.3.1
S 192.168.40.0/24 [150/0] via 10.1.2.1
R2
R2(config)#
iproute 10.1.1.0 255.255.255.0 10.1.4.1 150
R2(config)#
iproute 10.1.2.0 255.255.255.0 10.1.4.1 150
R2(config)#
iproute 10.1.3.0 255.255.255.0 10.1.4.1 150
R2(config)#
iproute 10.1.5.0 255.255.255.0 10.1.4.1 150
R2(config)#
iproute 192.168.10.0 255.255.255.0 10.1.4.1 150
R2(config)#
iproute 192.168.20.0 255.255.255.0 10.1.4.1 150
the only way to get across Corp is to go into it via 10.1.4.1
R2(config)#
do show ip route
10.0.0.0/24 is subnetted, 5 subnets
S 10.1.1.0 [150/0] via 10.1.4.1
S 10.1.2.0 [150/0] via 10.1.4.1
S 10.1.3.0 [150/0] via 10.1.4.1
C 10.1.4.0 is directly connected, Serial0/0/0
S 10.1.5.0 [150/0] via 10.1.4.1
172.16.0.0/24 is subnetted, 1 subnets
S 172.16.10.0 [150/0] via 10.1.4.1
S 192.168.10.0/24 [150/0] via 10.1.4.1
S 192.168.20.0/24 [150/0] via 10.1.4.1
C 192.168.30.0/24 is directly connected, FastEthernet0/0
C 192.168.40.0/24 is directly connected, FastEthernet0/1
R3
R3(config)#
ip route 10.1.1.0 255.255.255.0 fastethernet 0/0 150
R3(config)#
ip route 10.1.2.0 255.255.255.0 fastethernet 0/0 150
R3(config)#
ip route 10.1.3.0 255.255.255.0 fastethernet 0/0 150
R3(config)#
ip route 10.1.4.0 255.255.255.0 fastethernet 0/0 150
R3(config)#
ip route 192.168.10.0 255.255.255.0 fastethernet 0/0 150
R3(config)#
ip route 192.168.20.0 255.255.255.0 fastethernet 0/0 150
R3(config)#
ip route 192.168.30.0 255.255.255.0 fastethernet 0/0 150
R3(config)#
ip route 192.168.40.0 255.255.255.0 fastethernet 0/0 150
the only way to get across Corp is to EXIT R3 via F0/0
R3(config)#
do show ip route
10.0.0.0/8 is variably subnetted, 6 subnets, 2 masks
S 10.1.1.0/24 is directly connected, FastEthernet0/0
S 10.1.2.0/24 is directly connected, FastEthernet0/0
S 10.1.3.0/24 is directly connected, FastEthernet0/0
S 10.1.4.0/24 is directly connected, FastEthernet0/0
C 10.1.5.0/24 is directly connected, FastEthernet0/0
L 10.1.5.2/32 is directly connected, FastEthernet0/0
172.16.0.0/16 is variably subnetted, 2 subnets, 2 masks
C 172.16.10.0/24 is directly connected, Dot11Radio0/0/0
L 172.16.10.1/32 is directly connected, Dot11Radio0/0/0
S 192.168.10.0/24 is directly connected, FastEthernet0/0
S 192.168.20.0/24 is directly connected, FastEthernet0/0
S 192.168.30.0/24 is directly connected, FastEthernet0/0
S 192.168.40.0/24 is directly connected, FastEthernet0/0
before verifying connectivity across the network, we need to make sure all of our hosts are set. The book is giving us the IP addresses for the servers:
Server Gateway 10.1.1.1
ServerWeb 10.1.1.2
ServerEmail 10.1.1.3
ServerDNS 10.1.1.4
Now we can do some testing across the network:
R3#
ping 10.1.2.2
traverse Corp to R1
R3#
ping 10.1.1.1
traverse Corp to a Corp interface we arent directly connected to
R3#
ping 10.1.1.2
traverse Corp to Web server
R3#
ping 10.1.1.3
traverse Corp to Email server
R3#
ping 10.1.1.4
traverse Corp to DNS server
MobileUser
ping 192.168.10.2
traverse R3, Corp, R1 to Finance client
MobileUser
tracert 192.168.10.2
traverse R3, Corp, R1 to Finance client
Tracing route to 192.168.10.2 over a maximum of 30 hops:
1 19 ms 5 ms 20 ms 172.16.10.1
2 20 ms 6 ms 11 ms 10.1.5.1
3 11 ms 15 ms 10 ms 10.1.3.2
4 9 ms 13 ms 22 ms 192.168.10.2
Trace complete.
notice how the trace doesnt count an egress as a hop, only an ingress
ALSO NOTE that tracert is a Windows command.
the IOS equivalent is traceroute
notice how the output differs from the Windows command
R3
traceroute 192.168.10.2
Type escape sequence to abort.
Tracing the route to 192.168.10.2
1 10.1.5.1 0 msec 0 msec 0 msec
2 10.1.2.2 6 msec 0 msec 5 msec
3 192.168.10.2 1 msec 4 msec 3 msec
Default Routing
we could have done this on R3
R3(config)#
ip route 0.0.0.0 0.0.0.0 10.1.5.1
as an alternative to this configuration on R3
R3(config)#
ip route 10.1.1.0 255.255.255.0 fastethernet 0/0 150
R3(config)#
ip route 10.1.2.0 255.255.255.0 fastethernet 0/0 150
R3(config)#
ip route 10.1.3.0 255.255.255.0 fastethernet 0/0 150
R3(config)#
ip route 10.1.4.0 255.255.255.0 fastethernet 0/0 150
R3(config)#
ip route 192.168.10.0 255.255.255.0 fastethernet 0/0 150
R3(config)#
ip route 192.168.20.0 255.255.255.0 fastethernet 0/0 150
R3(config)#
ip route 192.168.30.0 255.255.255.0 fastethernet 0/0 150
R3(config)#
ip route 192.168.40.0 255.255.255.0 fastethernet 0/0 150
the only way to get across Corp is to EXIT R3 via F0/0
This is called default routing. It should only be used on 'stub routers'- those with only one exit path out of the network.
if you try to put a default route on a non-stub router, you could create loops, since there will be more than one path to other routers...
Think of a default route as a static route that uses a wildcard address and mask. The wildcard is 0.0.0.0
to further analyze this comparison, I'm going to remove the routes from R3...
R3(config)#
no ip route 10.1.1.0 255.255.255.0 fastethernet0/0 150
R3(config)#
no ip route 10.1.2.0 255.255.255.0 fastethernet0/0 150
R3(config)#
no ip route 10.1.3.0 255.255.255.0 fastethernet0/0 150
R3(config)#
no ip route 10.1.4.0 255.255.255.0 fastethernet0/0 150
R3(config)#
no ip route 192.168.10.0 255.255.255.0 fastethernet0/0 150
R3(config)#
no ip route 192.168.20.0 255.255.255.0 fastethernet0/0 150
R3(config)#
no ip route 192.168.30.0 255.255.255.0 fastethernet0/0 150
R3(config)#
no ip route 192.168.40.0 255.255.255.0 fastethernet0/0 150
and then set the default route instead.
R3#
ip route 0.0.0.0 0.0.0.0 10.1.5.1 --- ingress at next hop
OR
R3#
ip route 0.0.0.0 0.0.0.0 Fa0/0 --- egress interface
Then compare the output of show ip route
static routes set
R3#
show ip route
Gateway of last resort is not set
10.0.0.0/8 is variably subnetted, 6 subnets, 2 masks
S 10.1.1.0/24 is directly connected, FastEthernet0/0
S 10.1.2.0/24 is directly connected, FastEthernet0/0
S 10.1.3.0/24 is directly connected, FastEthernet0/0
S 10.1.4.0/24 is directly connected, FastEthernet0/0
C 10.1.5.0/24 is directly connected, FastEthernet0/0
L 10.1.5.2/32 is directly connected, FastEthernet0/0
172.16.0.0/16 is variably subnetted, 2 subnets, 2 masks
C 172.16.10.0/24 is directly connected, Dot11Radio0/0/0
L 172.16.10.1/32 is directly connected, Dot11Radio0/0/0
S 192.168.10.0/24 is directly connected, FastEthernet0/0
S 192.168.20.0/24 is directly connected, FastEthernet0/0
S 192.168.30.0/24 is directly connected, FastEthernet0/0
S 192.168.40.0/24 is directly connected, FastEthernet0/0
default route set
R3#
show ip route
Gateway of last resort is 10.1.5.1 to network 0.0.0.0
10.0.0.0/8 is variably subnetted, 2 subnets, 2 masks
C 10.1.5.0/24 is directly connected, FastEthernet0/0
L 10.1.5.2/32 is directly connected, FastEthernet0/0
172.16.0.0/16 is variably subnetted, 2 subnets, 2 masks
C 172.16.10.0/24 is directly connected, Dot11Radio0/0/0
L 172.16.10.1/32 is directly connected, Dot11Radio0/0/0
S* 0.0.0.0/0 [1/0] via 10.1.5.1
two directly connected networks- 10.1.5.0 and 172.16.10.0
anything not included in those networks goes to ingress of attached neighbor Corp 10.1.5.1
in this toplogy, that includes:
192.168.10.0
192.168.20.0
192.168.30.0
192.168.40.0
and
10.1.1.0
10.1.2.0
10.1.3.0
10.1.4.0
RIP Routing Information Protocol
R1(config)#
router ?
bgp Border Gateway Protocol (BGP)
eigrp Enhanced Interior Gateway Routing Protocol (EIGRP)
ospf Open Shortest Path First (OSPF)
rip Routing Information Protocol (RIP)
set RIP on Corp
Corp(config)#
router rip
Corp(config-router)#
network 10.0.0.0
set RIP on R1
R1(config)#
router rip
R1(config-router)#
network 10.0.0.0
R1 routing table
R1(config)#
do show ip route
10.0.0.0/24 is subnetted, 5 subnets
R 10.1.1.0 [120/1] via 10.1.2.1, 00:00:21, Serial0/0/0
[120/1] via 10.1.3.1, 00:00:21, Serial0/0/1
C 10.1.2.0 is directly connected, Serial0/0/0
C 10.1.3.0 is directly connected, Serial0/0/1
R 10.1.4.0 [120/1] via 10.1.2.1, 00:00:21, Serial0/0/0
[120/1] via 10.1.3.1, 00:00:21, Serial0/0/1
R 10.1.5.0 [120/1] via 10.1.2.1, 00:00:21, Serial0/0/0
[120/1] via 10.1.3.1, 00:00:21, Serial0/0/1
172.16.0.0/24 is subnetted, 1 subnets
S 172.16.10.0 [150/0] via 10.1.3.1
C 192.168.10.0/24 is directly connected, FastEthernet0/0
C 192.168.20.0/24 is directly connected, FastEthernet0/1
S 192.168.30.0/24 [150/0] via 10.1.3.1
S 192.168.40.0/24 [150/0] via 10.1.2.1
here's R1 before RIP, with only static routes set:
R1(config)#
do show ip route
10.0.0.0/24 is subnetted, 5 subnets
S 10.1.1.0 [150/0] via 10.1.2.1
C 10.1.2.0 is directly connected, Serial0/0/0
C 10.1.3.0 is directly connected, Serial0/0/1
S 10.1.4.0 [150/0] via 10.1.3.1
S 10.1.5.0 [150/0] via 10.1.2.1
172.16.0.0/24 is subnetted, 1 subnets
S 172.16.10.0 [150/0] via 10.1.3.1
C 192.168.10.0/24 is directly connected, FastEthernet0/0
C 192.168.20.0/24 is directly connected, FastEthernet0/1
S 192.168.30.0/24 [150/0] via 10.1.3.1
S 192.168.40.0/24 [150/0] via 10.1.2.1
These RIP routes are being advertised as available *to other RIP routers*.
CORP is advertisting THREE routes via RIP to R1 right now
10.1.1.0
10.1.4.0
10.1.5.0
access to those networks can be achieved by R1 by going THROUGH CORP via ingress .2.1 or .3.1
The advantage..... is that we didnt statically program these routes
we engaged RIP, on BOTH routers- R1 and Corp, and handed them BOTH the network "10.0.0.0"
So, why did RIP choose to display these particular routes
Keep in mind that the output above is from R1 only... In the context of the R1 ROUTER ONLY,
there are three relevant routes within the "10.0.0.0" parameter we specified. The three routes involve Corp.
Corp is sending RIP data about these routes to Corp.
Lets look closer at how this is happening:
here's our starting point before any RIP is set
here's our routing tables after i set RIP with 10.0.0.0 on both..
FIRST i set it on Corp, then R1.(per the book's instructions) As a result we are seeing RIP routes in R1 only....
then I went back to a fresh packet tracer file with no RIP set. And I set RIP in the opposite order;
FIRST i set it on R1, then Corp. And again, we are seeing RIP routes in R1 only....
I wanted to prove that it didnt matter which order we enabled RIP on the two routers. What matters here is that
we enable RIP on both of them with the criteria of 10.0.0.0
Recall the topology:
if Corp and R1 are set for RIP and given the criteria 10.0.0.0, meaning that we are trying to reach networks
within that range, then it follows that Corp will advertise 1.1.0, 1.4.0, and 1.5.0 to R1, because Corp stands between those networks
and R1
"Hi R1, I'm Corp I have three networks that fall inside 10.0.0.0, and you can reach them through me via .2.1 or .3.1"
It also follows that Corp's routing table shows no RIP routes- because R1 isnt advertising any. R1 doesnt have any networks
in the 10.0.0.0 range that Corp could reach
To further clarify this, we'll proceed with the book's instructions. We'll now set more RIP routes on R1
R1(config)#
router rip
R1(config-router)#
network 192.168.10.0
R1(config-router)#
network 192.168.20.0
Corp routing table before RIP set on R1:
Corp#
show ip route
10.0.0.0/8 is variably subnetted, 10 subnets, 2 masks
C 10.1.1.0/24 is directly connected, Vlan1
L 10.1.1.1/32 is directly connected, Vlan1
C 10.1.2.0/24 is directly connected, Serial0/0/0
L 10.1.2.1/32 is directly connected, Serial0/0/0
C 10.1.3.0/24 is directly connected, Serial0/0/1
L 10.1.3.1/32 is directly connected, Serial0/0/1
C 10.1.4.0/24 is directly connected, Serial0/1/0
L 10.1.4.1/32 is directly connected, Serial0/1/0
C 10.1.5.0/24 is directly connected, FastEthernet0/0
L 10.1.5.1/32 is directly connected, FastEthernet0/0
172.16.0.0/24 is subnetted, 1 subnets
S 172.16.10.0/24 [150/0] via 10.1.5.2
S 192.168.10.0/24 [150/0] via 10.1.2.2
S 192.168.20.0/24 [150/0] via 10.1.3.2
S 192.168.30.0/24 [150/0] via 10.1.4.2
S 192.168.40.0/24 [150/0] via 10.1.4.2
Corp routing table after RIP set on R1:
Gateway of last resort is not set
10.0.0.0/8 is variably subnetted, 10 subnets, 2 masks
C 10.1.1.0/24 is directly connected, Vlan1
L 10.1.1.1/32 is directly connected, Vlan1
C 10.1.2.0/24 is directly connected, Serial0/0/0
L 10.1.2.1/32 is directly connected, Serial0/0/0
C 10.1.3.0/24 is directly connected, Serial0/0/1
L 10.1.3.1/32 is directly connected, Serial0/0/1
C 10.1.4.0/24 is directly connected, Serial0/1/0
L 10.1.4.1/32 is directly connected, Serial0/1/0
C 10.1.5.0/24 is directly connected, FastEthernet0/0
L 10.1.5.1/32 is directly connected, FastEthernet0/0
nothing changed so far
172.16.0.0/24 is subnetted, 1 subnets
S 172.16.10.0/24 [150/0] via 10.1.5.2
no change
R 192.168.10.0/24 [120/1] via 10.1.2.2, 00:00:08, Serial0/0/0
[120/1] via 10.1.3.2, 00:00:08, Serial0/0/1
RIP overrides static- 2 paths available now
R 192.168.20.0/24 [120/1] via 10.1.2.2, 00:00:08, Serial0/0/0
[120/1] via 10.1.3.2, 00:00:08, Serial0/0/1
RIP overrides static- 2 paths available now
S 192.168.30.0/24 [150/0] via 10.1.4.2
no change
S 192.168.40.0/24 [150/0] via 10.1.4.2
no change
"Hi Corp- I'm R1 and I have zero networks
that fall inside 10.0.0.0, however I do have some networks that fall within
192.168.20.0 and 192.168.10.0
and you can reach them through me(R1) if you ingress at .1.2.2 or .1.3.2"
ok, we have the concept down. Time to proceed and set up RIP on R2............
R2(config)#
router rip
R2(config-router)#
network 10.0.0.0
R2(config-router)#
network 192.168.30.0
R2(config-router)#
network 192.168.40.0
R2 before RIP enabled
R2#
show ip route
10.0.0.0/24 is subnetted, 5 subnets
S 10.1.1.0 [150/0] via 10.1.4.1
S 10.1.2.0 [150/0] via 10.1.4.1
S 10.1.3.0 [150/0] via 10.1.4.1
C 10.1.4.0 is directly connected, Serial0/0/0
S 10.1.5.0 [150/0] via 10.1.4.1
172.16.0.0/24 is subnetted, 1 subnets
S 172.16.10.0 [150/0] via 10.1.4.1
S 192.168.10.0/24 [150/0] via 10.1.4.1
S 192.168.20.0/24 [150/0] via 10.1.4.1
C 192.168.30.0/24 is directly connected, FastEthernet0/0
C 192.168.40.0/24 is directly connected, FastEthernet0/1
R2 after RIP added
R2#
show ip route
10.0.0.0/24 is subnetted, 5 subnets
R 10.1.1.0 [120/1] via 10.1.4.1, 00:00:24, Serial0/0/0
from corp
R 10.1.2.0 [120/1] via 10.1.4.1, 00:00:24, Serial0/0/0
from corp
R 10.1.3.0 [120/1] via 10.1.4.1, 00:00:24, Serial0/0/0
from corp
C 10.1.4.0 is directly connected, Serial0/0/0
R 10.1.5.0 [120/1] via 10.1.4.1, 00:00:24, Serial0/0/0
from corp
172.16.0.0/24 is subnetted, 1 subnets
S 172.16.10.0 [150/0] via 10.1.4.1
R 192.168.10.0/24 [120/2] via 10.1.4.1, 00:00:24, Serial0/0/0
from R1 via corp
R 192.168.20.0/24 [120/2] via 10.1.4.1, 00:00:24, Serial0/0/0
from R1 via corp
C 192.168.30.0/24 is directly connected, FastEthernet0/0
C 192.168.40.0/24 is directly connected, FastEthernet0/1
now lets compare the Corp and R1 routing tables- before RIP was set on R2 and after
Corp before R2 RIP
Corp#
show ip route
10.0.0.0/8 is variably subnetted, 10 subnets, 2 masks
C 10.1.1.0/24 is directly connected, Vlan1
L 10.1.1.1/32 is directly connected, Vlan1
C 10.1.2.0/24 is directly connected, Serial0/0/0
L 10.1.2.1/32 is directly connected, Serial0/0/0
C 10.1.3.0/24 is directly connected, Serial0/0/1
L 10.1.3.1/32 is directly connected, Serial0/0/1
C 10.1.4.0/24 is directly connected, Serial0/1/0
L 10.1.4.1/32 is directly connected, Serial0/1/0
C 10.1.5.0/24 is directly connected, FastEthernet0/0
L 10.1.5.1/32 is directly connected, FastEthernet0/0
172.16.0.0/24 is subnetted, 1 subnets
S 172.16.10.0/24 [150/0] via 10.1.5.2
R 192.168.10.0/24 [120/1] via 10.1.2.2, 00:00:02, Serial0/0/0
[120/1] via 10.1.3.2, 00:00:02, Serial0/0/1
R 192.168.20.0/24 [120/1] via 10.1.2.2, 00:00:02, Serial0/0/0
[120/1] via 10.1.3.2, 00:00:02, Serial0/0/1
from R1
S 192.168.30.0/24 [150/0] via 10.1.4.2
S 192.168.40.0/24 [150/0] via 10.1.4.2
Corp after R2 RIP
Corp#
show ip route
10.0.0.0/8 is variably subnetted, 10 subnets, 2 masks
C 10.1.1.0/24 is directly connected, Vlan1
L 10.1.1.1/32 is directly connected, Vlan1
C 10.1.2.0/24 is directly connected, Serial0/0/0
L 10.1.2.1/32 is directly connected, Serial0/0/0
C 10.1.3.0/24 is directly connected, Serial0/0/1
L 10.1.3.1/32 is directly connected, Serial0/0/1
C 10.1.4.0/24 is directly connected, Serial0/1/0
L 10.1.4.1/32 is directly connected, Serial0/1/0
C 10.1.5.0/24 is directly connected, FastEthernet0/0
L 10.1.5.1/32 is directly connected, FastEthernet0/0
172.16.0.0/24 is subnetted, 1 subnets
S 172.16.10.0/24 [150/0] via 10.1.5.2
R 192.168.10.0/24 [120/1] via 10.1.2.2, 00:00:19, Serial0/0/0
[120/1] via 10.1.3.2, 00:00:19, Serial0/0/1
R 192.168.20.0/24 [120/1] via 10.1.2.2, 00:00:19, Serial0/0/0
[120/1] via 10.1.3.2, 00:00:19, Serial0/0/1
from R1
R 192.168.30.0/24 [120/1] via 10.1.4.2, 00:00:15, Serial0/1/0
R 192.168.40.0/24 [120/1] via 10.1.4.2, 00:00:15, Serial0/1/0
from R2
RIP on R2 is advertising .30.0 and .40.0 to Corp
R1 before R2 RIP
R1#
show ip route
10.0.0.0/24 is subnetted, 5 subnets
R 10.1.1.0 [120/1] via 10.1.2.1, 00:00:05, Serial0/0/0
[120/1] via 10.1.3.1, 00:00:05, Serial0/0/1
from Corp
C 10.1.2.0 is directly connected, Serial0/0/0
C 10.1.3.0 is directly connected, Serial0/0/1
R 10.1.4.0 [120/1] via 10.1.2.1, 00:00:05, Serial0/0/0
[120/1] via 10.1.3.1, 00:00:05, Serial0/0/1
R 10.1.5.0 [120/1] via 10.1.2.1, 00:00:05, Serial0/0/0
[120/1] via 10.1.3.1, 00:00:05, Serial0/0/1
from Corp
172.16.0.0/24 is subnetted, 1 subnets
S 172.16.10.0 [150/0] via 10.1.3.1
C 192.168.10.0/24 is directly connected, FastEthernet0/0
C 192.168.20.0/24 is directly connected, FastEthernet0/1
S 192.168.30.0/24 [150/0] via 10.1.3.1
S 192.168.40.0/24 [150/0] via 10.1.2.1
R1 after R2 RIP
R1#
show ip route
10.0.0.0/24 is subnetted, 5 subnets
R 10.1.1.0 [120/1] via 10.1.2.1, 00:00:06, Serial0/0/0
[120/1] via 10.1.3.1, 00:00:06, Serial0/0/1
from Corp
C 10.1.2.0 is directly connected, Serial0/0/0
C 10.1.3.0 is directly connected, Serial0/0/1
R 10.1.4.0 [120/1] via 10.1.2.1, 00:00:06, Serial0/0/0
[120/1] via 10.1.3.1, 00:00:06, Serial0/0/1
R 10.1.5.0 [120/1] via 10.1.2.1, 00:00:06, Serial0/0/0
[120/1] via 10.1.3.1, 00:00:06, Serial0/0/1
from Corp
172.16.0.0/24 is subnetted, 1 subnets
S 172.16.10.0 [150/0] via 10.1.3.1
C 192.168.10.0/24 is directly connected, FastEthernet0/0
C 192.168.20.0/24 is directly connected, FastEthernet0/1
R 192.168.30.0/24 [120/2] via 10.1.3.1, 00:00:06, Serial0/0/1
[120/2] via 10.1.2.1, 00:00:06, Serial0/0/0
R 192.168.40.0/24 [120/2] via 10.1.2.1, 00:00:06, Serial0/0/0
[120/2] via 10.1.3.1, 00:00:06, Serial0/0/1
from R2 via Corp
Now to set RIP on R3
R3(config)#
router rip
R3(config-router)#
network 10.0.0.0
R3(config-router)#
network 172.16.0.0
note that R3 is our only router with "gateway of last resort" set because we set a default route instead of static routes
As a result, we only see directly connected routes listed, along with a single "S*" for the default gateway
R3 before RIP
R3#
show ip route
Gateway of last resort is 10.1.5.1 to network 0.0.0.0
10.0.0.0/8 is variably subnetted, 2 subnets, 2 masks
C 10.1.5.0/24 is directly connected, FastEthernet0/0
L 10.1.5.2/32 is directly connected, FastEthernet0/0
172.16.0.0/16 is variably subnetted, 2 subnets, 2 masks
C 172.16.10.0/24 is directly connected, Dot11Radio0/0/0
L 172.16.10.1/32 is directly connected, Dot11Radio0/0/0
S* 0.0.0.0/0 [1/0] via 10.1.5.1
R3 after RIP
R3#
show ip route
Gateway of last resort is 10.1.5.1 to network 0.0.0.0
-------------------------------------------------------------
10.0.0.0/8 is variably subnetted, 6 subnets, 2 masks
R 10.1.1.0/24 [120/1] via 10.1.5.1, 00:00:21, FastEthernet0/0
R 10.1.2.0/24 [120/1] via 10.1.5.1, 00:00:21, FastEthernet0/0
R 10.1.3.0/24 [120/1] via 10.1.5.1, 00:00:21, FastEthernet0/0
R 10.1.4.0/24 [120/1] via 10.1.5.1, 00:00:21, FastEthernet0/0
from Corp
C 10.1.5.0/24 is directly connected, FastEthernet0/0
L 10.1.5.2/32 is directly connected, FastEthernet0/0
-------------------------------------------------------------
172.16.0.0/16 is variably subnetted, 2 subnets, 2 masks
C 172.16.10.0/24 is directly connected, Dot11Radio0/0/0
L 172.16.10.1/32 is directly connected, Dot11Radio0/0/0
R 192.168.10.0/24 [120/2] via 10.1.5.1, 00:00:21, FastEthernet0/0
R 192.168.20.0/24 [120/2] via 10.1.5.1, 00:00:21, FastEthernet0/0
From R1 via Corp
R 192.168.30.0/24 [120/2] via 10.1.5.1, 00:00:21, FastEthernet0/0
R 192.168.40.0/24 [120/2] via 10.1.5.1, 00:00:21, FastEthernet0/0
From R2 via Corp
S* 0.0.0.0/0 [1/0] via 10.1.5.1
Corp before R3 RIP
Corp#
show ip route
10.0.0.0/8 is variably subnetted, 10 subnets, 2 masks
C 10.1.1.0/24 is directly connected, Vlan1
L 10.1.1.1/32 is directly connected, Vlan1
C 10.1.2.0/24 is directly connected, Serial0/0/0
L 10.1.2.1/32 is directly connected, Serial0/0/0
C 10.1.3.0/24 is directly connected, Serial0/0/1
L 10.1.3.1/32 is directly connected, Serial0/0/1
C 10.1.4.0/24 is directly connected, Serial0/1/0
L 10.1.4.1/32 is directly connected, Serial0/1/0
C 10.1.5.0/24 is directly connected, FastEthernet0/0
L 10.1.5.1/32 is directly connected, FastEthernet0/0
172.16.0.0/24 is subnetted, 1 subnets
S 172.16.10.0/24 [150/0] via 10.1.5.2
R 192.168.10.0/24 [120/1] via 10.1.2.2, 00:00:26, Serial0/0/0
[120/1] via 10.1.3.2, 00:00:26, Serial0/0/1
R 192.168.20.0/24 [120/1] via 10.1.2.2, 00:00:26, Serial0/0/0
[120/1] via 10.1.3.2, 00:00:26, Serial0/0/1
from R1 via corp
R 192.168.30.0/24 [120/1] via 10.1.4.2, 00:00:21, Serial0/1/0
R 192.168.40.0/24 [120/1] via 10.1.4.2, 00:00:21, Serial0/1/0
from R2 via corp
Corp after R3 RIP
Corp#
show ip route
10.0.0.0/8 is variably subnetted, 10 subnets, 2 masks
C 10.1.1.0/24 is directly connected, Vlan1
L 10.1.1.1/32 is directly connected, Vlan1
C 10.1.2.0/24 is directly connected, Serial0/0/0
L 10.1.2.1/32 is directly connected, Serial0/0/0
C 10.1.3.0/24 is directly connected, Serial0/0/1
L 10.1.3.1/32 is directly connected, Serial0/0/1
C 10.1.4.0/24 is directly connected, Serial0/1/0
L 10.1.4.1/32 is directly connected, Serial0/1/0
C 10.1.5.0/24 is directly connected, FastEthernet0/0
L 10.1.5.1/32 is directly connected, FastEthernet0/0
172.16.0.0/16 is variably subnetted, 2 subnets, 2 masks
R 172.16.0.0/16 [120/1] via 10.1.5.2, 00:00:13, FastEthernet0/0
S 172.16.10.0/24 [150/0] via 10.1.5.2
from R3
R 192.168.10.0/24 [120/1] via 10.1.3.2, 00:00:13, Serial0/0/1
[120/1] via 10.1.2.2, 00:00:13, Serial0/0/0
R 192.168.20.0/24 [120/1] via 10.1.3.2, 00:00:13, Serial0/0/1
[120/1] via 10.1.2.2, 00:00:13, Serial0/0/0
from R1 via corp
R 192.168.30.0/24 [120/1] via 10.1.4.2, 00:00:24, Serial0/1/0
R 192.168.40.0/24 [120/1] via 10.1.4.2, 00:00:24, Serial0/1/0
from R2 via corp
R2 before R3 RIP
R2#
show ip route
10.0.0.0/24 is subnetted, 5 subnets
R 10.1.1.0 [120/1] via 10.1.4.1, 00:00:15, Serial0/0/0
R 10.1.2.0 [120/1] via 10.1.4.1, 00:00:15, Serial0/0/0
R 10.1.3.0 [120/1] via 10.1.4.1, 00:00:15, Serial0/0/0
from Corp
C 10.1.4.0 is directly connected, Serial0/0/0
R 10.1.5.0 [120/1] via 10.1.4.1, 00:00:15, Serial0/0/0
from Corp
172.16.0.0/24 is subnetted, 1 subnets
S 172.16.10.0 [150/0] via 10.1.4.1
R 192.168.10.0/24 [120/2] via 10.1.4.1, 00:00:15, Serial0/0/0
R 192.168.20.0/24 [120/2] via 10.1.4.1, 00:00:15, Serial0/0/0
from R1 via Corp
C 192.168.30.0/24 is directly connected, FastEthernet0/0
C 192.168.40.0/24 is directly connected, FastEthernet0/1
R2 after R3 RIP
R2#
show ip route
10.0.0.0/24 is subnetted, 5 subnets
R 10.1.1.0 [120/1] via 10.1.4.1, 00:00:20, Serial0/0/0
R 10.1.2.0 [120/1] via 10.1.4.1, 00:00:20, Serial0/0/0
R 10.1.3.0 [120/1] via 10.1.4.1, 00:00:20, Serial0/0/0
from Corp
C 10.1.4.0 is directly connected, Serial0/0/0
R 10.1.5.0 [120/1] via 10.1.4.1, 00:00:20, Serial0/0/0
from Corp
172.16.0.0/16 is variably subnetted, 2 subnets, 2 masks
R 172.16.0.0/16 [120/2] via 10.1.4.1, 00:00:20, Serial0/0/0
S 172.16.10.0/24 [150/0] via 10.1.4.1
from R3 via Corp
R 192.168.10.0/24 [120/2] via 10.1.4.1, 00:00:20, Serial0/0/0
R 192.168.20.0/24 [120/2] via 10.1.4.1, 00:00:20, Serial0/0/0
from R1 via Corp
C 192.168.30.0/24 is directly connected, FastEthernet0/0
C 192.168.40.0/24 is directly connected, FastEthernet0/1
R1 before R3 RIP
R1#
show ip route
10.0.0.0/24 is subnetted, 5 subnets
R 10.1.1.0 [120/1] via 10.1.2.1, 00:00:04, Serial0/0/0
[120/1] via 10.1.3.1, 00:00:04, Serial0/0/1
C 10.1.2.0 is directly connected, Serial0/0/0
C 10.1.3.0 is directly connected, Serial0/0/1
R 10.1.4.0 [120/1] via 10.1.2.1, 00:00:04, Serial0/0/0
[120/1] via 10.1.3.1, 00:00:04, Serial0/0/1
R 10.1.5.0 [120/1] via 10.1.2.1, 00:00:04, Serial0/0/0
[120/1] via 10.1.3.1, 00:00:04, Serial0/0/1
from Corp
172.16.0.0/24 is subnetted, 1 subnets
S 172.16.10.0 [150/0] via 10.1.3.1
C 192.168.10.0/24 is directly connected, FastEthernet0/0
C 192.168.20.0/24 is directly connected, FastEthernet0/1
R 192.168.30.0/24 [120/2] via 10.1.2.1, 00:00:04, Serial0/0/0
[120/2] via 10.1.3.1, 00:00:04, Serial0/0/1
R 192.168.40.0/24 [120/2] via 10.1.2.1, 00:00:04, Serial0/0/0
[120/2] via 10.1.3.1, 00:00:04, Serial0/0/1
from R2 via Corp
R1 after R3 RIP
R1#
show ip route
10.0.0.0/24 is subnetted, 5 subnets
R 10.1.1.0 [120/1] via 10.1.3.1, 00:00:03, Serial0/0/1
[120/1] via 10.1.2.1, 00:00:03, Serial0/0/0
C 10.1.2.0 is directly connected, Serial0/0/0
C 10.1.3.0 is directly connected, Serial0/0/1
R 10.1.4.0 [120/1] via 10.1.3.1, 00:00:03, Serial0/0/1
[120/1] via 10.1.2.1, 00:00:03, Serial0/0/0
R 10.1.5.0 [120/1] via 10.1.3.1, 00:00:03, Serial0/0/1
[120/1] via 10.1.2.1, 00:00:03, Serial0/0/0
from Corp
172.16.0.0/16 is variably subnetted, 2 subnets, 2 masks
R 172.16.0.0/16 [120/2] via 10.1.3.1, 00:00:03, Serial0/0/1
[120/2] via 10.1.2.1, 00:00:03, Serial0/0/0
S 172.16.10.0/24 [150/0] via 10.1.3.1
from R3 via Corp
C 192.168.10.0/24 is directly connected, FastEthernet0/0
C 192.168.20.0/24 is directly connected, FastEthernet0/1
R 192.168.30.0/24 [120/2] via 10.1.3.1, 00:00:03, Serial0/0/1
[120/2] via 10.1.2.1, 00:00:03, Serial0/0/0
R 192.168.40.0/24 [120/2] via 10.1.3.1, 00:00:03, Serial0/0/1
[120/2] via 10.1.2.1, 00:00:03, Serial0/0/0
from R2 via Corp
Verifying Configurations
in addition to
show ip route
we can also use
show ip protocols
and
debug rip ip
Corp#
show ip protocols
Routing Protocol is "rip"
Sending updates every 30 seconds, next due in 11 seconds
Invalid after 180 seconds, hold down 180, flushed after 240
Outgoing update filter list for all interfaces is not set
Incoming update filter list for all interfaces is not set
Redistributing: rip
Default version control: send version 1, receive any version
Interface Send Recv Triggered RIP Key-chain
Vlan1 1 2 1
FastEthernet0/0 1 2 1
Serial0/0/1 1 2 1
Serial0/1/0 1 2 1
Serial0/0/0 1 2 1
Automatic network summarization is in effect
Maximum path: 4
Routing for Networks:
10.0.0.0
Passive Interface(s):
Routing Information Sources:
Gateway Distance Last Update
10.1.5.2 120 00:00:00
10.1.3.2 120 00:00:10
10.1.2.2 120 00:00:10
10.1.4.2 120 00:00:20
Distance: (default is 120)
R3#
debug ip rip
R3#RIP: received v1 update from 10.1.5.1 on FastEthernet0/0
10.1.1.0 in 1 hops
10.1.2.0 in 1 hops
10.1.3.0 in 1 hops
10.1.4.0 in 1 hops
192.168.10.0 in 2 hops
192.168.20.0 in 2 hops
192.168.30.0 in 2 hops
192.168.40.0 in 2 hops
R3#RIP: sending v1 update to 255.255.255.255 via Dot11Radio0/0/0 (172.16.10.1)
RIP: build update entries
network 10.0.0.0 metric 1
network 192.168.10.0 metric 3
network 192.168.20.0 metric 3
network 192.168.30.0 metric 3
network 192.168.40.0 metric 3
RIP: sending v1 update to 255.255.255.255 via FastEthernet0/0 (10.1.5.2)
RIP: build update entries
network 172.16.0.0 metric 1
output loops until manually disabled..............
R3#
undebug all
All possible debugging has been turned off
Note that due to the Split Horizon rule, R3 is not sending all of it's known RIP data to Corp.
It is sending all known RIP data out of the wifi interface (even there though there's no router that way),
but it is ONLY sending data about the wifi network back to Corp; data that Corp doesnt already have
Now lets look at some examples with sample routers..
I got hung up on these two examples because I found the
wording to be a bit confusing. Also there was subnetting involved that I was able to figure out, but threw me at first
First source of confusion- we have two seperate examples, and I was mixing them up.
The examples are:
Use the debug ip rip command to both:
discover a problem
and figure out how RIP was configured on a router from a different sample network
The conclusion regarding 'figuring out how RIP is configured' on this router, is that RIP networks are set as 10.0.0.0 and 172.16.0.0.
We determined that we are not the 'first source' of info on the 192.168.1.0 nertwork, since it is a metric of 2. We are sending out RIP data on that network,
but that RIP data is made availbale to us via another router.
I also got tripped up on the fact that RA is sending out S0/0 which corresponds 10.0.8.1,
and then receiving on the same interface S0/0 from an ip address of 10.0.15.0 on the other side of the link
I was able to determine that these two address are actually on the same subnet. My initial assumption was that the network address for the link is 10.0.0.0.
The problem doesn't give the subnet mask- I guessed it as /20 by using a 16 block since we can see that the third octet seems to move in 8's
if the network starts at 10.0.0.0 and we use /20 with 16 block, we would indeed have a last host address of 10.0.15.254, so 10.0.15.2 would be a valid host.
So there was a twist to this problem which needed subnetting to solve. It wasnt particulary releveant to the subject of RIP, but I was curious why the address on
the other side of that link looked so strange.
The problem also points out that we can determine there are 'at least' two routers participating in RIP here since we are sending RIP data out two interfaces but
only receiving RIP data on one interface. I'm unclear on why its worded this way; we know we are a RIP router- the fact that we are receiving data on one interface
would suggest there is 'at least one more' RIP router out there.
that's it for this example. Back to the original statement-
Use the debug ip rip command to both discover a problem and figure out
how RIP was configured on a router from a different sample network
We just 'figured out how RIP was configured on a router'.. The second example is regarding 'discovering a problem', although it is mentioned first.
The second example will use debug ip rip and show ip route to find a problem with the network
it looks like RIP data for 172.16.20.0 was received on S0/0, and then that interface was bumped out of the routing table entry for that network in favor of a static route.
ok, moving on now to RIP V2
RIP V2
enable it on all four routers
Corp(config)
router rip
Corp(config-router)
version 2
R1(config)
router rip
R1(config-router)
version 2
R2(config)
router rip
R2(config-router)
version 2
R3(config)
router rip
R3(config-router)
version 2
We'll use R1 to compare RIPv1 and RIPv2
RIPv1
R1(config)
debug ip rip
R1#RIP: sending v1 update to 255.255.255.255 via FastEthernet0/0 (192.168.10.1)
RIP: build update entries
network 10.0.0.0 metric 1
network 172.16.0.0 metric 3
network 192.168.20.0 metric 1
network 192.168.30.0 metric 3
network 192.168.40.0 metric 3
RIP: sending v1 update to 255.255.255.255 via FastEthernet0/1 (192.168.20.1)
RIP: build update entries
network 10.0.0.0 metric 1
network 172.16.0.0 metric 3
network 192.168.10.0 metric 1
network 192.168.30.0 metric 3
network 192.168.40.0 metric 3
RIP: sending v1 update to 255.255.255.255 via Serial0/0/0 (10.1.2.2)
RIP: build update entries
network 10.1.3.0 metric 1
network 192.168.10.0 metric 1
network 192.168.20.0 metric 1
RIP: sending v1 update to 255.255.255.255 via Serial0/0/1 (10.1.3.2)
RIP: build update entries
network 10.1.2.0 metric 1
network 192.168.10.0 metric 1
network 192.168.20.0 metric 1
RIPv2
R1(config)
debug ip rip
R1#RIP: sending v2 update to 224.0.0.9 via FastEthernet0/0 (192.168.10.1)
RIP: build update entries
10.0.0.0/8 via 0.0.0.0, metric 1, tag 0
172.16.0.0/16 via 0.0.0.0, metric 3, tag 0
192.168.20.0/24 via 0.0.0.0, metric 1, tag 0
192.168.30.0/24 via 0.0.0.0, metric 3, tag 0
192.168.40.0/24 via 0.0.0.0, metric 3, tag 0
RIP: sending v2 update to 224.0.0.9 via FastEthernet0/1 (192.168.20.1)
RIP: build update entries
10.0.0.0/8 via 0.0.0.0, metric 1, tag 0
172.16.0.0/16 via 0.0.0.0, metric 3, tag 0
192.168.10.0/24 via 0.0.0.0, metric 1, tag 0
192.168.30.0/24 via 0.0.0.0, metric 3, tag 0
192.168.40.0/24 via 0.0.0.0, metric 3, tag 0
RIP: sending v2 update to 224.0.0.9 via Serial0/0/0 (10.1.2.2)
RIP: build update entries
10.1.3.0/24 via 0.0.0.0, metric 1, tag 0
192.168.10.0/24 via 0.0.0.0, metric 1, tag 0
192.168.20.0/24 via 0.0.0.0, metric 1, tag 0
RIP: sending v2 update to 224.0.0.9 via Serial0/0/1 (10.1.3.2)
RIP: build update entries
10.1.2.0/24 via 0.0.0.0, metric 1, tag 0
192.168.10.0/24 via 0.0.0.0, metric 1, tag 0
192.168.20.0/24 via 0.0.0.0, metric 1, tag 0
R1(config)
show ip protocols
Routing Protocol is "rip"
Sending updates every 30 seconds, next due in 13 seconds
Invalid after 180 seconds, hold down 180, flushed after 240
Outgoing update filter list for all interfaces is not set
Incoming update filter list for all interfaces is not set
Redistributing: rip
Default version control: send version 2, receive 2
Interface Send Recv Triggered RIP Key-chain
FastEthernet0/0 2 2
FastEthernet0/1 2 2
Serial0/0/0 2 2
Serial0/0/1 2 2
Automatic network summarization is in effect
Maximum path: 4
Routing for Networks:
10.0.0.0
192.168.10.0
192.168.20.0
Passive Interface(s):
Routing Information Sources:
Gateway Distance Last Update
10.1.3.1 120 00:00:21
10.1.2.1 120 00:00:21
Distance: (default is 120)
final task of this chapter
Enable a default route out to the internet , and advertise via RIP
R3(config)#
interface s0/1/0 (this is only for example, so I am not adding a serial card to R3)
R3(config-if)#
ip addr 172.16.10.5 255.255.255.252
R3(config-if)#
exit
R3(config)#
ip route 0.0.0.0 0.0.0.0 s0/0
R3(config)#
ip default-network 172.16.0.0 tells other routers via RIP that default WAN route is through R3
Chapter 8 Exam Essentials IP Routing
1. Describe the Basic IP routing process
frame changes at each hop, but packet doesnt change EXCEPT that the TTL field in the IP header decrements
2. List the information required by a router to successfully route packets
destination IP address, location of other routers, possible routers to all remote networks,
the best route to each network, how to maintain and maintain routing info
3. Describe how MAC addresses are used during the routing process
a MAC will never pass a router interface. MACs will change between router interfaces
4. View and interpret the routing table of a router
use show ip route to see the table
a "C" indicates directly connected, an "R" indicates RIP provided the route info, "S" means static
5. differentiate the three types of routing
static- manually configured
dynamic- routers automatically share info via protocol
default- a special route is configured for all traffic without a more specific destination network found in the table
6. Compare and contrast static and dynamic routing
static routing creates no routing update traffic which means less overhead on the routers and links- but it must be
configured manually and can't react if links are lost.
dynamic routing creates update traffic, but it can react to outages and choose the best route when multiple routes exist to the same network
7. Configure static routes at the CLI
route [dest network] [mask] [next hop address OR exit interface] [admin distance] [permanent]
Ex:
Corp(config)#
ip route 192.168.10.0 255.255.255.0 10.1.2.2 150
8. Create a default route
ip route 0.0.0.0 0.0.0.0 [ip address OR exit interface]
Ex:
R3(config)#
ip route 0.0.0.0 0.0.0.0 10.1.5.1 (ingress at Corp router- use if R3 cant identify route)
9. Understand administrative distance and its role in the selection of the best route
an integer from 0 (most trusted) to 255 (no traffic will pass via this route).
All routing protocols are assigned an AD but it can be changed at the CLI
10. Differentiate distance-vector, link-state, and hybrid routing protocols
distance vector- based on hop count (RIP)
link-state- multiple factors such as bandwidth and delay
hybrid- uses both
11. List mechanisms used to prevent routing loops in the network
max hop count, split horizon, route poisoning, holddown counters
12. Describe the counts used the operation of RIP
route update timer- (30) interval between routing updates
route invalid timer- (180, update x 3) before a route is determined invalid
holddown timer-(180) time info is supressed when a link is lost
route flush timer- (240) seconds before invalid and removal
13. Configure RIP routing
router rip
network x.x.x.x
the network(s) you want to advertise from your router. It only works if the other router has RIP enabled.
By enabling RIP, you are able to RECEIVE RIP data from other RIP routers.
by specifying a network, you are SENDING RIP data on that network
14. Identify commands used to verify RIP routing
show ip route will provide contents of the routing table with codes (R, C, S)
debug ip rip will show RIP updates being sent and received
15. Describe the differences between RIPv1 and RIPv2
RIPv1 sends a broadcast (255.255.255.255) every 30 seconds and has an AD of 120.
RIPv1 is classful only, does not send any mask info. No authentication between routers.
RIPv2 sends multicasts (224.0.0.9) every 30 seconds and sends mask info, which allows it to support classless networking, RIPv2 also supports
autentication between routers.
Chapter 8 Written Lab 8.0
1. At the appropriate prompt, create a static route to network 172.16.10.0/24 with a next-hop
gateway of 172.16.20.1 and an administrative distance of 150.
Router(config)#
ip route 172.16.10.0 255.255.255.0 172.16.20.1 150
2. When a PC sends a packet to another PC in a remote network, what destination IP address and MAC address will
be in the frame that it sends to it's default gateway?
the gateway interface MAC and the remote PC's IP
3. At the appropriate prompt, create a default route to 172.16.40.1
Router(config)#
ip route 0.0.0.0 0.0.0.0 172.16.40.1
"to" is the wrong word.. we are going TO any route VIA 172.16.40.1
4. If you are using default routing in a classless environment, what command must also be used?
Router(config)#
ip classless
5. On which type of network is a default route most beneficial?
stub
6. At the appropriate prompt, display the routing table on your router
Router#
show ip route
7. When creating a static or default route, you dont have to use the next-hop ip address;
you can instead use the ____________
exit interface
8. True/False: To reach a destination host, you must know the MAC address of the remote host
false, you need the MAC of your router
9. True/False: To reach a destination host, you must know the IP address of the remote host
true
10. At the appropriate prompt, execute the command required on a DCE serial interface that is not required
on a DTE serial interface
Router(config-if)#
clock rate X
11. At the appropriate prompt, enable RIP routing on the interface with the IP address 10.0.0.1/24
Router(config)#
router rip
Router(config-router)#
network 10.0.0.0
RIPv1 is CLASSFUL only... use the classful mask based on the first octet given
12. At the appropriate prompt, prevent a router from propagating IP information out serial 1
Router(config)#
router rip
Router(config-router)#
passive-interface S0/1
can receive RIP data but will not send
13. What routing loop prevention mechanism sends out a maximum hop count as soon as a link fails?
route poisoning
14. What routing loop prevention mechanism suppresses the resending of routing information to an interface
through which it was received?
split horizon
15. At the appropriate prompt display RIP routing updates as they are sent and received on the router
to the console session
Router#
debug ip rip
to turn it off:
Router#
undebug all
Chapter 8 Hands-on Labs
For these labs we will need a network with three routers.
Lab 8.1 Creating Static routes
first set the interfaces, then program the static routes
LabA(config)#
int s0/0/0
LabA(config-if)#
ip addr 172.16.20.1
LabA(config-if)#
int f0/0
LabA(config-if)#
ip addr 172.16.10.1
-----------------------------------------------------------------
LabA(config)#
ip route 172.16.30.0 255.255.255.0 172.16.20.2
LabA(config)#
ip route 172.16.40.0 255.255.255.0 172.16.20.2
LabB(config)#
int s0/0/0
LabB(config-if)#
ip addr 172.16.20.2
LabB(config-if)#
int s0/0/1
LabB(config-if)#
ip addr 172.16.30.1
-----------------------------------------------------------------
LabB(config)#
ip route 172.16.10.0 255.255.255.0 172.16.20.1
LabB(config)#
ip route 172.16.40.0 255.255.255.0 172.16.30.2
LabC(config)#
int s0/0/0
LabC(config-if)#
ip addr 172.16.30.2
LabC(config-if)#
int f0/0
LabC(config-if)#
ip addr 172.16.40.1
-----------------------------------------------------------------
LabC(config)#
ip route 172.16.10.0 255.255.255.0 172.16.30.1
LabC(config)#
ip route 172.16.20.0 255.255.255.0 172.16.30.1
Lab 8.2 RIP Configuration
remove the static routes, enable and configure RIP with the classful network id that covers the routes you want to advertise
LabA(config)#
no ip route 172.16.30.0 255.255.255.0 172.16.20.2
LabA(config)#
no ip route 172.16.40.0 255.255.255.0 172.16.20.2
LabA(config)#
router rip
LabA(config-router)#
network 172.16.0.0
LabA(config-router)#
do show ip route
Gateway of last resort is not set
172.16.0.0/16 is variably subnetted, 5 subnets, 2 masks
C 172.16.10.0/24 is directly connected, FastEthernet0/0
L 172.16.10.1/32 is directly connected, FastEthernet0/0
C 172.16.20.0/24 is directly connected, Serial0/0/0
L 172.16.20.1/32 is directly connected, Serial0/0/0
R 172.16.30.0/24 [120/1] via 172.16.20.2, 00:00:07, Serial0/0/0
from Lab B
LabB(config)#
no ip route 172.16.10.0 255.255.255.0 172.16.20.1
LabB(config)#
no ip route 172.16.40.0 255.255.255.0 172.16.30.2
LabB(config)#
router rip
LabB(config-router)#
network 172.16.0.0
LabB(config-router)#
do show ip route
Gateway of last resort is not set
172.16.0.0/16 is variably subnetted, 5 subnets, 2 masks
R 172.16.10.0/24 [120/1] via 172.16.20.1, 00:00:13, Serial0/0/0
from LabA
C 172.16.20.0/24 is directly connected, Serial0/0/0
L 172.16.20.2/32 is directly connected, Serial0/0/0
C 172.16.30.0/24 is directly connected, Serial0/0/1
L 172.16.30.1/32 is directly connected, Serial0/0/1
LabC(config)#
no ip route 172.16.10.0 255.255.255.0 172.16.30.1
LabC(config)#
no ip route 172.16.20.0 255.255.255.0 172.16.30.1
LabC(config)#
router rip
LabC(config-router)#
network 172.16.0.0
LabC(config-router)#
do show ip route
Gateway of last resort is not set
172.16.0.0/16 is variably subnetted, 3 subnets, 2 masks
R 172.16.20.0/24 [120/1] via 172.16.30.1, 00:00:05, Serial0/0/0
from LabB
C 172.16.30.0/24 is directly connected, Serial0/0/0
L 172.16.30.2/32 is directly connected, Serial0/0/0
Chapter 8 Review Questions
1. The Acme company uses a router named Gateway to connect to its ISP. The address of the ISP router is 206.143.5.2.
Which three commands could be configured on the gateway router to allow internet access to the entire network?
Set a default route:
Gateway(config)#
ip route 0.0.0.0 0.0.0.0 206.143.5.2 next hop IP
Gateway(config)#
ip route 0.0.0.0 0.0.0.0 S/0 exit interface instead of next hop IP
Gateway(config)#
ip default-network 206.143.5.0 next hop IP
2. What command will prevent RIP routing updates from exiting an interface but will sill allow the interface to receive RIP updates?
Router(config-if)#
passive-interface
3. Which two statemnts are true about ip route 172.16.4.0 255.255.255.0 192.168.4.2?
the command establishes a static route
the default admin distance is used (since we didnt give an AD argument)
4. What two destination addresses will be used by HostA to send data to the HTTPS server as shown in the following network?
MAC of RouterA f0/0 interface
IP address of the server
5. Which two statements are true about this output?
RIP: received v1 update from 192.168.40.2 on S0/1
192.168.50.0 in 16 hops (inaccessible)
RIP: sending v1 update to 255.255.255.255 via F0/0 (192.168.30.1)
RIP: build update entries
network 192.168.20.0 metric 1
network 192.168.40.0 metric 1
network 192.168.50.0 metric 16
RIP: sending v1 update to 255.255.255.255 via S0/1 (192.168.40.1)
true:
there are at least two routers exchanging information
192.168.40.2 will be successful
FALSE
there are three interfaces on the router participating in this update
false because we only see two interfaces represented in the output: S0/1(twice) and F0/0
a ping to 192.168.50.1 will be successful
false because that route has a metric of 16; it's unreachable
6. Describe split horizon
will not advertise a route back the the same router it was learned from
7. Which would be true if HostA is trying to communicate to HostB and interface F0/0 of RouterC goes down, as shown in the graphic?
RouterC will send an ICMP 'destination unreachable type' message to inform HostA that HostB is unreachable
8. Which two statements are true regarding classless routing protocols?
VLSM is permitted
RIPv2 supports classless
9. Which two are true regarding distance-vector vs link-state?
Distance vector sends the whole routing table out all active interfaces(even if a router isnt on the other end)at periodic time intervals
Link-state sends updates containing the state of its own links to all routers in the inter-network
10. Which command display RIP routing updates?
debug ip rip
11. What does RIPv2 use to prvent routing loops?
split horizon stops an update from being send on the same interface it was received
holdown timers allow time for a network to become stable in the case of a flapping link
12. A network administrator views the output from the show ip route command. A network that is advertised
by both RIP and EIGRP appears in the routing table flagged an EIGRP route. Why is the RIP route to this network not used in this routing table?
EIGRP has a lower AD.
RIP=120
OSPP=110
IGRP=110
EIGRP=90
13. You type debug ip rip on your router console and see that 172.16.10.0 is being advertised to you with a metric of 16. What does this mean?
it is inaccessible. in RIP if you see a route advertised with a metric of 16, it's inaccessible
14. What metric does RIPv2 use to find the best path to the remote network?
distance aka hop count
15. The Corporate router receives an IP packet with a source IP address of 192.168.214.20 and a destination address of 192.168.22.3. Looking at the output from the Corp router,
what will the router do with this packet?
Corp# show ip route
[cut]
R 192.168.215.0 [120/2] via 192.168.20.2, Serail0/0
R 192.168.115.0 [120/1] via 192.168.20.0, Serial0/0
R 192.168.30.0 [120/1] via 192.168.20.2, Serial0/0
C 192.168.20.0 is directly connected, Serial0/0
C 192.168.214.0 is directly connected, FastEthernet0/0
Since there is no route to that network, the router will discard the packet and send an ICMP destination unreachable message out F0/0 back the the source network
16. If your routing table has a static, a RIP and an EIGRP route to the same network, which route will be used by default?
Static routes have an admin distance of 1 by default. Unless you change it, a static route will always be used over any other
dynamically learned route.
17. You have the following routing table. Which network will NOT be placed in the neighbor routing table?
R 192.168.30.0/24 [120/1] via 192.168.40.1, Serial 0
C 192.168.40.0/24 is directly connected, Serial 0
172.16.0.0/2 is subnetted, 1 subnets
C 172.16.30.0 is directly connected, Loopback0
R 192.168.20.0/24 [120/1] via 192.168.40.1, Serial 0
R 10.0.0.0/8 [120/15] via 192.168.40.1, Serial 0
C 192.168.50.0/24 is directly connected, Ethernet 0
10.0.0.0 cant be placed in neighboring routing table because it is at 15 hops. 16 hops is invalid in RIP
18. Two connected routers are configured only with RIP. What will be the result when a router receives a routing update that contains a
higher-cost path to a network already in it's routing table?
The router will ignore the update because it is higher cost. When a routing update is received, the router first checks the AD and always chooses
the route with the lowest AD.
19.Which is true about route poisoning?
The router sets the metric for a downed link to "infinity".
20. Which is true about RIPv2?
it has all the same timers as RIPv1
------------------------------------------------------------------------------
END CHAPTER 8
54 hours 1-28 thru 2-14-22
original total 143 hours
11.5 hours review 12-23,24,26-22
review total hours 32
book page 428/822
avg 20 min/page (reading and exercises/labs)
Chapter 9 EIGRP and OSPF
pages 427-502, start 2-14-22-M
What is EIGRP?
Note it's not officially on CCNA 200-301 but it is still important to learn
Enhanced IGRP is a classless, enchanced distance vector protocol that uses the concept of an autonomous system to describe
the set of contigous routers that run the same routing protocol and share routing information.
Features:
Support for IP and IPv6 via protocol-dependent modules (seperate routing tables)
Considered classless
Support for summaries and discontiguous networks
Eficient neighbor discovery
communication via RTP- Reliable Transport Protocol
best path selection via Diffusing Updae Algorithm DUAL
Cisco considers EIGRP a "distance-vector" routing protocol
or an "advanced distance-vector" protocol
or a "hybrid" protocol
Configuring EIGRP on our network
------------------------------------------------------------------------------------------------------------------------------------
Corp(config)#
router eigrp ?
<1-65535> Autonomous system number
Corp(config)#
router eigrp 10
R2(config-router)#
network 10.0.0.0
after eigrp on R1- links from Corp to R1 are up
%DUAL-5-NBRCHANGE: IP-EIGRP 10: Neighbor 10.1.3.2 (Serial0/0/1) is up: new adjacency
%DUAL-5-NBRCHANGE: IP-EIGRP 10: Neighbor 10.1.2.2 (Serial0/0/0) is up: new adjacency
after eigrp on R2- link from Corp to R2 is up
%DUAL-5-NBRCHANGE: IP-EIGRP 10: Neighbor 10.1.4.2 (Serial0/1/0) is up: new adjacency
after eigrp on R3- link from Corp to R3 is up
%DUAL-5-NBRCHANGE: IP-EIGRP 10: Neighbor 10.1.5.2 (FastEthernet0/0) is up: new adjacency
------------------------------------------------------------------------------------------------------------------------------------
R1(config)#
router eigrp 10
R1(config-router)#
network 10.0.0.0
after eigrp on R1- link from R1 to Corp is up
%DUAL-5-NBRCHANGE: IP-EIGRP 10: Neighbor 10.1.3.1 (Serial0/0/1) is up: new adjacency
%DUAL-5-NBRCHANGE: IP-EIGRP 10: Neighbor 10.1.2.1 (Serial0/0/0) is up: new adjacency
R1(config-router)#
network 192.168.10.0
R1(config-router)#
network 192.168.20.0
------------------------------------------------------------------------------------------------------------------------------------
R2(config)#
router eigrp 10
R2(config-router)#
network 10.0.0.0
after eigrp on R2- link from R2 to Corp is up
%DUAL-5-NBRCHANGE: IP-EIGRP 10: Neighbor 10.1.4.1 (Serial0/0/0) is up: new adjacency
R1(config-router)#
network 192.168.30.0
R1(config-router)#
network 192.168.40.0
------------------------------------------------------------------------------------------------------------------------------------
R3(config)#
router eigrp 10
R3(config-router)#
network 10.0.0.0
after eigrp on R3- link from R3 to Corp is up
%DUAL-5-NBRCHANGE: IP-EIGRP 10: Neighbor 10.1.5.1 (FastEthernet0/0) is up: new adjacency
R1(config-router)#
network 172.16.0.0
------------------------------------------------------------------------------------------------------------------------------------
Corp#
show ip route
Gateway of last resort is not set
Gateway of last resort is not set
10.0.0.0/8 is variably subnetted, 10 subnets, 2 masks
C 10.1.1.0/24 is directly connected, Vlan1
L 10.1.1.1/32 is directly connected, Vlan1
C 10.1.2.0/24 is directly connected, Serial0/0/0
L 10.1.2.1/32 is directly connected, Serial0/0/0
C 10.1.3.0/24 is directly connected, Serial0/0/1
L 10.1.3.1/32 is directly connected, Serial0/0/1
C 10.1.4.0/24 is directly connected, Serial0/1/0
L 10.1.4.1/32 is directly connected, Serial0/1/0
C 10.1.5.0/24 is directly connected, FastEthernet0/0
L 10.1.5.1/32 is directly connected, FastEthernet0/0
172.16.0.0/16 is variably subnetted, 2 subnets, 2 masks
R 172.16.0.0/16 [120/1] via 10.1.5.2, 00:00:17, FastEthernet0/0
D 172.16.10.0/24 [90/28160] via 10.1.5.2, 00:00:16, FastEthernet0/0
via R3
D 192.168.10.0/24 [90/2172416] via 10.1.2.2, 00:19:13, Serial0/0/0
[90/2172416] via 10.1.3.2, 00:19:13, Serial0/0/1
D 192.168.20.0/24 [90/2172416] via 10.1.3.2, 00:19:05, Serial0/0/1
[90/2172416] via 10.1.2.2, 00:19:05, Serial0/0/0
via R1
D 192.168.30.0/24 [90/2172416] via 10.1.4.2, 00:01:31, Serial0/1/0
D 192.168.40.0/24 [90/2172416] via 10.1.4.2, 00:01:08, Serial0/1/0
via R2
The "D" routes are for DUAL- Diffusing Update Algorithm, indicating they are EIGRP routes.
Note that we have RIP and EIGRP set currently
------------------------------------------------------------------------------------------------------------------------------------
R1#
show ip route
Gateway of last resort is not set
10.0.0.0/8 is variably subnetted, 6 subnets, 2 masks
D 10.0.0.0/8 is a summary, 00:25:28, Null0
D 10.1.1.0/24 [90/27769856] via 10.1.2.1, 00:31:33, Serial0/0/0
[90/27769856] via 10.1.3.1, 00:31:30, Serial0/0/1
via Corp
C 10.1.2.0/24 is directly connected, Serial0/0/0
C 10.1.3.0/24 is directly connected, Serial0/0/1
D 10.1.4.0/24 [90/2681856] via 10.1.2.1, 00:31:33, Serial0/0/0
[90/2681856] via 10.1.3.1, 00:31:30, Serial0/0/1
D 10.1.5.0/24 [90/2172416] via 10.1.2.1, 00:31:33, Serial0/0/0
[90/2172416] via 10.1.3.1, 00:31:30, Serial0/0/1
via Corp
172.16.0.0/16 is variably subnetted, 2 subnets, 2 masks
R 172.16.0.0/16 [120/2] via 10.1.2.1, 00:00:07, Serial0/0/0
[120/2] via 10.1.3.1, 00:00:07, Serial0/0/1
D 172.16.10.0/24 [90/2172416] via 10.1.2.1, 00:06:31, Serial0/0/0
[90/2172416] via 10.1.3.1, 00:06:31, Serial0/0/1
via Corp
C 192.168.10.0/24 is directly connected, FastEthernet0/0
C 192.168.20.0/24 is directly connected, FastEthernet0/1
D 192.168.30.0/24 [90/2684416] via 10.1.3.1, 00:07:46, Serial0/0/1
[90/2684416] via 10.1.2.1, 00:07:46, Serial0/0/0
D 192.168.40.0/24 [90/2684416] via 10.1.2.1, 00:07:23, Serial0/0/0
[90/2684416] via 10.1.3.1, 00:07:23, Serial0/0/1
via Corp
------------------------------------------------------------------------------------------------------------------------------------
R2#
show ip route
Gateway of last resort is not set
10.0.0.0/8 is variably subnetted, 6 subnets, 2 masks
D 10.0.0.0/8 is a summary, 00:13:09, Null0
D 10.1.1.0/24 [90/27769856] via 10.1.4.1, 00:36:53, Serial0/0/0
D 10.1.2.0/24 [90/2681856] via 10.1.4.1, 00:36:53, Serial0/0/0
D 10.1.3.0/24 [90/2681856] via 10.1.4.1, 00:36:53, Serial0/0/0
via Corp
C 10.1.4.0/24 is directly connected, Serial0/0/0
D 10.1.5.0/24 [90/2172416] via 10.1.4.1, 00:36:53, Serial0/0/0
via Corp
172.16.0.0/16 is variably subnetted, 2 subnets, 2 masks
R 172.16.0.0/16 [120/2] via 10.1.4.1, 00:00:23, Serial0/0/0
D 172.16.10.0/24 [90/2172416] via 10.1.4.1, 00:11:54, Serial0/0/0
via Corp
D 192.168.10.0/24 [90/2684416] via 10.1.4.1, 00:30:51, Serial0/0/0
D 192.168.20.0/24 [90/2684416] via 10.1.4.1, 00:30:43, Serial0/0/0
via Corp
C 192.168.30.0/24 is directly connected, FastEthernet0/0
C 192.168.40.0/24 is directly connected, FastEthernet0/1
------------------------------------------------------------------------------------------------------------------------------------
R3#
show ip route
Gateway of last resort is 10.1.5.1 to network 0.0.0.0
10.0.0.0/8 is variably subnetted, 6 subnets, 2 masks
D 10.1.1.0/24 [90/25628160] via 10.1.5.1, 00:37:20, FastEthernet0/0
D 10.1.2.0/24 [90/2172416] via 10.1.5.1, 00:37:15, FastEthernet0/0
D 10.1.3.0/24 [90/2172416] via 10.1.5.1, 00:37:20, FastEthernet0/0
D 10.1.4.0/24 [90/2172416] via 10.1.5.1, 00:37:20, FastEthernet0/0
via Corp
C 10.1.5.0/24 is directly connected, FastEthernet0/0
L 10.1.5.2/32 is directly connected, FastEthernet0/0
172.16.0.0/16 is variably subnetted, 2 subnets, 2 masks
C 172.16.10.0/24 is directly connected, Dot11Radio0/0/0
L 172.16.10.1/32 is directly connected, Dot11Radio0/0/0
D 192.168.10.0/24 [90/2174976] via 10.1.5.1, 00:31:10, FastEthernet0/0
D 192.168.20.0/24 [90/2174976] via 10.1.5.1, 00:31:02, FastEthernet0/0
via Corp and R1
D 192.168.30.0/24 [90/2174976] via 10.1.5.1, 00:13:28, FastEthernet0/0
D 192.168.40.0/24 [90/2174976] via 10.1.5.1, 00:13:05, FastEthernet0/0
via Corp and R2
S* 0.0.0.0/0 [1/0] via 10.1.5.1
------------------------------------------------------------------------------------------------------------------------------------
turn off auto summary on each router
------------------------------------------------------------------------------------------------------------------------------------
Corp(config)#
router eigrp 10
Corp(config-router)#
no auto-summary
------------------------------------------------------------------------------------------------------------------------------------
R1(config)#
router eigrp 10
R1(config-router)#
no auto-summary
------------------------------------------------------------------------------------------------------------------------------------
R2(config)#
router eigrp 10
R2(config-router)#
no auto-summary
------------------------------------------------------------------------------------------------------------------------------------
R3(config)#
router eigrp 10
R3(config-router)#
no auto-summary
------------------------------------------------------------------------------------------------------------------------------------
compare Corp before and after auto summary turned off
------------------------------------------------------------------------------------------------------------------------------------
auto summary on
Corp#
show ip route
Gateway of last resort is not set
10.0.0.0/8 is variably subnetted, 10 subnets, 2 masks
C 10.1.1.0/24 is directly connected, Vlan1
L 10.1.1.1/32 is directly connected, Vlan1
C 10.1.2.0/24 is directly connected, Serial0/0/0
L 10.1.2.1/32 is directly connected, Serial0/0/0
C 10.1.3.0/24 is directly connected, Serial0/0/1
L 10.1.3.1/32 is directly connected, Serial0/0/1
C 10.1.4.0/24 is directly connected, Serial0/1/0
L 10.1.4.1/32 is directly connected, Serial0/1/0
C 10.1.5.0/24 is directly connected, FastEthernet0/0
L 10.1.5.1/32 is directly connected, FastEthernet0/0
172.16.0.0/16 is variably subnetted, 2 subnets, 2 masks
R 172.16.0.0/16 [120/1] via 10.1.5.2, 00:00:17, FastEthernet0/0
D 172.16.10.0/24 [90/28160] via 10.1.5.2, 00:00:16, FastEthernet0/0
via R3
D 192.168.10.0/24 [90/2172416] via 10.1.2.2, 00:19:13, Serial0/0/0
[90/2172416] via 10.1.3.2, 00:19:13, Serial0/0/1
D 192.168.20.0/24 [90/2172416] via 10.1.3.2, 00:19:05, Serial0/0/1
[90/2172416] via 10.1.2.2, 00:19:05, Serial0/0/0
via R1
D 192.168.30.0/24 [90/2172416] via 10.1.4.2, 00:01:31, Serial0/1/0
D 192.168.40.0/24 [90/2172416] via 10.1.4.2, 00:01:08, Serial0/1/0
via R2
auto summary off
Corp#
show ip route
Gateway of last resort is not set
10.0.0.0/8 is variably subnetted, 10 subnets, 2 masks
C 10.1.1.0/24 is directly connected, Vlan1
L 10.1.1.1/32 is directly connected, Vlan1
C 10.1.2.0/24 is directly connected, Serial0/0/0
L 10.1.2.1/32 is directly connected, Serial0/0/0
C 10.1.3.0/24 is directly connected, Serial0/0/1
L 10.1.3.1/32 is directly connected, Serial0/0/1
C 10.1.4.0/24 is directly connected, Serial0/1/0
L 10.1.4.1/32 is directly connected, Serial0/1/0
C 10.1.5.0/24 is directly connected, FastEthernet0/0
L 10.1.5.1/32 is directly connected, FastEthernet0/0
172.16.0.0/16 is variably subnetted, 2 subnets, 2 masks
R 172.16.0.0/16 [120/1] via 10.1.5.2, 00:00:12, FastEthernet0/0
D 172.16.10.0/24 [90/28160] via 10.1.5.2, 00:45:29, FastEthernet0/0
via R3
D 192.168.10.0/24 [90/2172416] via 10.1.2.2, 00:01:08, Serial0/0/0
[90/2172416] via 10.1.3.2, 00:01:08, Serial0/0/1
D 192.168.20.0/24 [90/2172416] via 10.1.2.2, 00:01:08, Serial0/0/0
[90/2172416] via 10.1.3.2, 00:01:08, Serial0/0/1
via R1
D 192.168.30.0/24 [90/2172416] via 10.1.4.2, 00:00:46, Serial0/1/0
D 192.168.40.0/24 [90/2172416] via 10.1.4.2, 00:00:46, Serial0/1/0
via R2
We are still seeing an auto summarized route- 172.16.0.0 coming from R3.
The book discusses enabling EIGRP auto summary on all four routers- nothing is said about disabling it within RIP or turning off RIP.
RIP auto summarizes by default. We cant get rid of this auto summary route while RIP is on.
Moving on...
VERIFYING EIGRP
several commands available to verify and troubleshoot
show ip route
show the entire routing table
show ip route eigrp
show only EIGRP entries in the routing table
show ip eigrp neighbors
show all EIGRP neigbors
show ip eigrp topology
show entries in the EIGRP topology table
show ip protocols
shows routing protocols configuration
debug eigrp packet
shows hello packets sent/received between adjacent routers
debug ip eigrp events
shows EIGRP changes and updates as they occur on your network
lets take a look at the state of our 4 routers. RIP and EIGRP are running on each.
Notice how this command is giving different outputs between the two different IOS versions
IOS 15.1
Corp#
show ip protocols
Routing Protocol is "eigrp 10 "
Outgoing update filter list for all interfaces is not set
Incoming update filter list for all interfaces is not set
Default networks flagged in outgoing updates
Default networks accepted from incoming updates
Redistributing: eigrp 10
EIGRP-IPv4 Protocol for AS(10)
Metric weight K1=1, K2=0, K3=1, K4=0, K5=0
NSF-aware route hold timer is 240
Router-ID: 10.1.1.1
Topology : 0 (base)
Active Timer: 3 min
Distance: internal 90 external 170
Maximum path: 4
Maximum hopcount 100
Maximum metric variance 1
Automatic Summarization: disabled
Automatic address summarization:
Maximum path: 4
Routing for Networks:
10.0.0.0
Routing Information Sources:
Gateway Distance Last Update
10.1.5.2 90 0
10.1.3.2 90 6464
10.1.2.2 90 6795
10.1.4.2 90 7955
Distance: internal 90 external 170
Routing Protocol is "rip"
Sending updates every 30 seconds, next due in 10 seconds
Invalid after 180 seconds, hold down 180, flushed after 240
Outgoing update filter list for all interfaces is not set
Incoming update filter list for all interfaces is not set
Redistributing: rip
Default version control: send version 2, receive 2
Interface Send Recv Triggered RIP Key-chain
Vlan1 2 2
FastEthernet0/0 2 2
Serial0/1/0 2 2
Serial0/0/1 2 2
Serial0/0/0 2 2
Automatic network summarization is in effect
Maximum path: 4
Routing for Networks:
10.0.0.0
Passive Interface(s):
Routing Information Sources:
Gateway Distance Last Update
10.1.5.2 120 00:00:12
10.1.3.2 120 00:00:16
10.1.2.2 120 00:00:16
10.1.4.2 120 00:00:13
Distance: (default is 120)
IOS 12.4
R1#
show ip protocols
Routing Protocol is "eigrp 10 "
Outgoing update filter list for all interfaces is not set
Incoming update filter list for all interfaces is not set
Default networks flagged in outgoing updates
Default networks accepted from incoming updates
EIGRP metric weight K1=1, K2=0, K3=1, K4=0, K5=0
EIGRP maximum hopcount 100
EIGRP maximum metric variance 1
Redistributing: eigrp 10
Automatic network summarization is not in effect
Maximum path: 4
Routing for Networks:
10.0.0.0
192.168.10.0
192.168.20.0
Routing Information Sources:
Gateway Distance Last Update
10.1.3.1 90 6465
10.1.2.1 90 6794
Distance: internal 90 external 170
Routing Protocol is "rip"
Sending updates every 30 seconds, next due in 21 seconds
Invalid after 180 seconds, hold down 180, flushed after 240
Outgoing update filter list for all interfaces is not set
Incoming update filter list for all interfaces is not set
Redistributing: rip
Default version control: send version 2, receive 2
Interface Send Recv Triggered RIP Key-chain
FastEthernet0/0 2 2
FastEthernet0/1 2 2
Serial0/0/0 2 2
Serial0/0/1 2 2
Automatic network summarization is not in effect
Maximum path: 4
Routing for Networks:
10.0.0.0
192.168.10.0
192.168.20.0
Passive Interface(s):
Routing Information Sources:
Gateway Distance Last Update
10.1.3.1 120 00:00:06
10.1.2.1 120 00:00:06
Distance: (default is 120)
IOS 12.4
R2#
show ip protocols
Routing Protocol is "eigrp 10 "
Outgoing update filter list for all interfaces is not set
Incoming update filter list for all interfaces is not set
Default networks flagged in outgoing updates
Default networks accepted from incoming updates
EIGRP metric weight K1=1, K2=0, K3=1, K4=0, K5=0
EIGRP maximum hopcount 100
EIGRP maximum metric variance 1
Redistributing: eigrp 10
Automatic network summarization is not in effect
Maximum path: 4
Routing for Networks:
10.0.0.0
192.168.30.0
192.168.40.0
Routing Information Sources:
Gateway Distance Last Update
10.1.4.1 90 7955
Distance: internal 90 external 170
Routing Protocol is "rip"
Sending updates every 30 seconds, next due in 11 seconds
Invalid after 180 seconds, hold down 180, flushed after 240
Outgoing update filter list for all interfaces is not set
Incoming update filter list for all interfaces is not set
Redistributing: rip
Default version control: send version 2, receive 2
Interface Send Recv Triggered RIP Key-chain
FastEthernet0/0 2 2
FastEthernet0/1 2 2
Serial0/0/0 2 2
Automatic network summarization is in effect
Maximum path: 4
Routing for Networks:
10.0.0.0
192.168.30.0
192.168.40.0
Passive Interface(s):
Routing Information Sources:
Gateway Distance Last Update
10.1.4.1 120 00:00:20
Distance: (default is 120)
IOS 15.1
R3#
show ip protocols
Routing Protocol is "eigrp 10 "
Outgoing update filter list for all interfaces is not set
Incoming update filter list for all interfaces is not set
Default networks flagged in outgoing updates
Default networks accepted from incoming updates
Redistributing: eigrp 10
EIGRP-IPv4 Protocol for AS(10)
Metric weight K1=1, K2=0, K3=1, K4=0, K5=0
NSF-aware route hold timer is 240
Router-ID: 10.1.5.2
Topology : 0 (base)
Active Timer: 3 min
Distance: internal 90 external 170
Maximum path: 4
Maximum hopcount 100
Maximum metric variance 1
Automatic Summarization: disabled
Automatic address summarization:
Maximum path: 4
Routing for Networks:
10.0.0.0
172.16.0.0
Routing Information Sources:
Gateway Distance Last Update
10.1.5.1 90 0
Distance: internal 90 external 170
Routing Protocol is "rip"
Sending updates every 30 seconds, next due in 27 seconds
Invalid after 180 seconds, hold down 180, flushed after 240
Outgoing update filter list for all interfaces is not set
Incoming update filter list for all interfaces is not set
Redistributing: rip
Default version control: send version 2, receive 2
Interface Send Recv Triggered RIP Key-chain
Dot11Radio0/0/0 2 2
FastEthernet0/0 2 2
Automatic network summarization is not in effect
Maximum path: 4
Routing for Networks:
10.0.0.0
172.16.0.0
Passive Interface(s):
Routing Information Sources:
Gateway Distance Last Update
10.1.5.1 120 00:00:02
Distance: (default is 120)
I'm also noticing that we have inconsistent auto-summarization settings- I was having trouble with this earlier. The book discusses
getting rid of the 172.16.0.0 summarized route in the EIGRP settings. I was not able to get rid of it, I think because RIP is still on, and RIP forces auto-summary
Part of the challenge here is that the book is strictly dealing with IOS 12.4
I will now make sure to turn auto summary off for both RIP and EIGRP on each of the four routers.
OK the part I am forgetting is that we are running RIP V2 which does not force auto-summary but runs it optionally, and we must turn it off to avoid auto summarization.
Corp(config)#
router rip
Corp(config-router)#
no auto-summary
Corp(config-router)#
router eigrp 10
Corp(config-router)#
no auto-summary
R1(config)#
router rip
R1(config-router)#
no auto-summary
R1(config-router)#
router eigrp 10
R1(config-router)#
no auto-summary
R1(config)#
router rip
R1(config-router)#
no auto-summary
R1(config-router)#
router eigrp 10
R2(config-router)#
no auto-summary
R3(config)#
router rip
R3(config-router)#
no auto-summary
R3(config-router)#
router eigrp 10
R3(config-router)#
no auto-summary
and lets see how the output looks now. This time I'll do show ip protocols and
show ip route side by side for each router
IOS 15.1
Corp#
show ip protocols
Routing Protocol is "eigrp 10 "
Outgoing update filter list for all interfaces is not set
Incoming update filter list for all interfaces is not set
Default networks flagged in outgoing updates
Default networks accepted from incoming updates
Redistributing: eigrp 10
EIGRP-IPv4 Protocol for AS(10)
Metric weight K1=1, K2=0, K3=1, K4=0, K5=0
NSF-aware route hold timer is 240
Router-ID: 10.1.1.1
Topology : 0 (base)
Active Timer: 3 min
Distance: internal 90 external 170
Maximum path: 4
Maximum hopcount 100
Maximum metric variance 1
Automatic Summarization: disabled
Automatic address summarization:
Maximum path: 4
Routing for Networks:
10.0.0.0
Routing Information Sources:
Gateway Distance Last Update
10.1.5.2 90 0
10.1.3.2 90 6464
10.1.2.2 90 6795
10.1.4.2 90 7955
Distance: internal 90 external 170
Routing Protocol is "rip" doesnt necessarily mean RIPv1
Sending updates every 30 seconds, next due in 3 seconds
Invalid after 180 seconds, hold down 180, flushed after 240
Outgoing update filter list for all interfaces is not set
Incoming update filter list for all interfaces is not set
Redistributing: rip
Default version control: send version 2, receive 2 RIPv2 is specified
Interface Send Recv Triggered RIP Key-chain
Vlan1 2 2
FastEthernet0/0 2 2
Serial0/1/0 2 2
Serial0/0/1 2 2
Serial0/0/0 2 2
Automatic network summarization is not in effect
Maximum path: 4
Routing for Networks:
10.0.0.0
Passive Interface(s):
Routing Information Sources:
Gateway Distance Last Update
10.1.5.2 120 00:00:02
10.1.3.2 120 00:00:21
10.1.2.2 120 00:00:21
10.1.4.2 120 00:00:04
Distance: (default is 120)
IOS 15.1
Corp#
show ip route
Gateway of last resort is not set
10.0.0.0/8 is variably subnetted, 10 subnets, 2 masks
C 10.1.1.0/24 is directly connected, Vlan1
L 10.1.1.1/32 is directly connected, Vlan1
C 10.1.2.0/24 is directly connected, Serial0/0/0
L 10.1.2.1/32 is directly connected, Serial0/0/0
C 10.1.3.0/24 is directly connected, Serial0/0/1
L 10.1.3.1/32 is directly connected, Serial0/0/1
C 10.1.4.0/24 is directly connected, Serial0/1/0
L 10.1.4.1/32 is directly connected, Serial0/1/0
C 10.1.5.0/24 is directly connected, FastEthernet0/0
L 10.1.5.1/32 is directly connected, FastEthernet0/0
172.16.0.0/24 is subnetted, 1 subnets
D 172.16.10.0/24 [90/28160] via 10.1.5.2, 00:57:25, FastEthernet0/0
D 192.168.10.0/24 [90/2172416] via 10.1.3.2, 00:57:20, Serial0/0/1
[90/2172416] via 10.1.2.2, 00:57:20, Serial0/0/0
D 192.168.20.0/24 [90/2172416] via 10.1.3.2, 00:57:20, Serial0/0/1
[90/2172416] via 10.1.2.2, 00:57:20, Serial0/0/0
D 192.168.30.0/24 [90/2172416] via 10.1.4.2, 00:57:19, Serial0/1/0
D 192.168.40.0/24 [90/2172416] via 10.1.4.2, 00:57:19, Serial0/1/0
IOS 12.4
R1#
show ip protocols
Routing Protocol is "eigrp 10 "
Outgoing update filter list for all interfaces is not set
Incoming update filter list for all interfaces is not set
Default networks flagged in outgoing updates
Default networks accepted from incoming updates
EIGRP metric weight K1=1, K2=0, K3=1, K4=0, K5=0
EIGRP maximum hopcount 100
EIGRP maximum metric variance 1
Redistributing: eigrp 10
Automatic network summarization is not in effect
Maximum path: 4
Routing for Networks:
10.0.0.0
192.168.10.0
192.168.20.0
Routing Information Sources:
Gateway Distance Last Update
10.1.3.1 90 6465
10.1.2.1 90 6794
Distance: internal 90 external 170
Routing Protocol is "rip"
Sending updates every 30 seconds, next due in 26 seconds
Invalid after 180 seconds, hold down 180, flushed after 240
Outgoing update filter list for all interfaces is not set
Incoming update filter list for all interfaces is not set
Redistributing: rip
Default version control: send version 2, receive 2
Interface Send Recv Triggered RIP Key-chain
FastEthernet0/0 2 2
FastEthernet0/1 2 2
Serial0/0/0 2 2
Serial0/0/1 2 2
Automatic network summarization is not in effect
Maximum path: 4
Routing for Networks:
10.0.0.0
192.168.10.0
192.168.20.0
Passive Interface(s):
Routing Information Sources:
Gateway Distance Last Update
10.1.3.1 120 00:00:03
10.1.2.1 120 00:00:03
Distance: (default is 120)
IOS 12.4
R1#
show ip route
Gateway of last resort is not set
10.0.0.0/24 is subnetted, 5 subnets
D 10.1.1.0 [90/27769856] via 10.1.3.1, 00:54:47, Serial0/0/1
[90/27769856] via 10.1.2.1, 00:54:47, Serial0/0/0
C 10.1.2.0 is directly connected, Serial0/0/0
C 10.1.3.0 is directly connected, Serial0/0/1
D 10.1.4.0 [90/2681856] via 10.1.3.1, 00:54:47, Serial0/0/1
[90/2681856] via 10.1.2.1, 00:54:47, Serial0/0/0
D 10.1.5.0 [90/2172416] via 10.1.3.1, 00:54:47, Serial0/0/1
[90/2172416] via 10.1.2.1, 00:54:47, Serial0/0/0
172.16.0.0/24 is subnetted, 1 subnets
D 172.16.10.0 [90/2172416] via 10.1.3.1, 00:54:47, Serial0/0/1
[90/2172416] via 10.1.2.1, 00:54:47, Serial0/0/0
C 192.168.10.0/24 is directly connected, FastEthernet0/0
C 192.168.20.0/24 is directly connected, FastEthernet0/1
D 192.168.30.0/24 [90/2684416] via 10.1.3.1, 00:54:46, Serial0/0/1
[90/2684416] via 10.1.2.1, 00:54:46, Serial0/0/0
D 192.168.40.0/24 [90/2684416] via 10.1.3.1, 00:54:46, Serial0/0/1
[90/2684416] via 10.1.2.1, 00:54:46, Serial0/0/0
note that the DUAL routes being advertised from the 10.0.0.0 networks are all specific to the third octet.. that's because we are reading those routes
from their source, aka the router which they are directly connected to, Corp.
and on Corp, those networks were added to the interfaces with a /24 mask.
so even though our EIGRP config doesnt specifically include /24 networks.. we told it to include anything with a 10.x.x.x
Corp is advertising to R1 our /24 network interfaces that have a 10 in the first octet, EXCEPT the two which are directly connected to R1
10.1.1.0
10.1.4.0
10.1.5.0
are assumed to be the subnets based on the info we configured, which was 10.1.4.1/24 on corp, and 10.1.4.2/24 on r2 s0/0/0
nowhere in this configuration, have we entered the 10.1.4.0 network.
EIGRP is figuring it out based on the /24 mask we gave when assiging he IPs to the interfaces
IOS 12.4
R2#
show ip protocols
Routing Protocol is "eigrp 10 "
Outgoing update filter list for all interfaces is not set
Incoming update filter list for all interfaces is not set
Default networks flagged in outgoing updates
Default networks accepted from incoming updates
EIGRP metric weight K1=1, K2=0, K3=1, K4=0, K5=0
EIGRP maximum hopcount 100
EIGRP maximum metric variance 1
Redistributing: eigrp 10
Automatic network summarization is not in effect
Maximum path: 4
Routing for Networks:
10.0.0.0
192.168.30.0
192.168.40.0
Routing Information Sources:
Gateway Distance Last Update
10.1.4.1 90 7955
Distance: internal 90 external 170
Routing Protocol is "rip"
Sending updates every 30 seconds, next due in 18 seconds
Invalid after 180 seconds, hold down 180, flushed after 240
Outgoing update filter list for all interfaces is not set
Incoming update filter list for all interfaces is not set
Redistributing: rip
Default version control: send version 2, receive 2
Interface Send Recv Triggered RIP Key-chain
FastEthernet0/0 2 2
FastEthernet0/1 2 2
Serial0/0/0 2 2
Automatic network summarization is not in effect
Maximum path: 4
Routing for Networks:
10.0.0.0
192.168.30.0
192.168.40.0
Passive Interface(s):
Routing Information Sources:
Gateway Distance Last Update
10.1.4.1 120 00:00:07
Distance: (default is 120)
IOS 12.4
R2#
show ip route
Gateway of last resort is not set
10.0.0.0/24 is subnetted, 5 subnets
D 10.1.1.0 [90/27769856] via 10.1.4.1, 00:59:10, Serial0/0/0
D 10.1.2.0 [90/2681856] via 10.1.4.1, 00:59:10, Serial0/0/0
D 10.1.3.0 [90/2681856] via 10.1.4.1, 00:59:10, Serial0/0/0
C 10.1.4.0 is directly connected, Serial0/0/0
D 10.1.5.0 [90/2172416] via 10.1.4.1, 00:59:10, Serial0/0/0
172.16.0.0/24 is subnetted, 1 subnets
D 172.16.10.0 [90/2172416] via 10.1.4.1, 00:59:10, Serial0/0/0
D 192.168.10.0/24 [90/2684416] via 10.1.4.1, 00:59:10, Serial0/0/0
D 192.168.20.0/24 [90/2684416] via 10.1.4.1, 00:59:10, Serial0/0/0
C 192.168.30.0/24 is directly connected, FastEthernet0/0
C 192.168.40.0/24 is directly connected, FastEthernet0/1
IOS 15.1
R3#
show ip protocols
Routing Protocol is "eigrp 10 "
Outgoing update filter list for all interfaces is not set
Incoming update filter list for all interfaces is not set
Default networks flagged in outgoing updates
Default networks accepted from incoming updates
Redistributing: eigrp 10
EIGRP-IPv4 Protocol for AS(10)
Metric weight K1=1, K2=0, K3=1, K4=0, K5=0
NSF-aware route hold timer is 240
Router-ID: 10.1.5.2
Topology : 0 (base)
Active Timer: 3 min
Distance: internal 90 external 170
Maximum path: 4
Maximum hopcount 100
Maximum metric variance 1
Automatic Summarization: disabled
Automatic address summarization:
Maximum path: 4
Routing for Networks:
10.0.0.0
172.16.0.0
Routing Information Sources:
Gateway Distance Last Update
10.1.5.1 90 0
Distance: internal 90 external 170
Routing Protocol is "rip"
Sending updates every 30 seconds, next due in 15 seconds
Invalid after 180 seconds, hold down 180, flushed after 240
Outgoing update filter list for all interfaces is not set
Incoming update filter list for all interfaces is not set
Redistributing: rip
Default version control: send version 2, receive 2
Interface Send Recv Triggered RIP Key-chain
Dot11Radio0/0/0 2 2
FastEthernet0/0 2 2
Automatic network summarization is not in effect
Maximum path: 4
Routing for Networks:
10.0.0.0
172.16.0.0
Passive Interface(s):
Routing Information Sources:
Gateway Distance Last Update
10.1.5.1 120 00:00:14
Distance: (default is 120)
IOS 15.1
R3#
show ip route
Gateway of last resort is 10.1.5.1 to network 0.0.0.0
10.0.0.0/8 is variably subnetted, 6 subnets, 2 masks
D 10.1.1.0/24 [90/25628160] via 10.1.5.1, 00:59:52, FastEthernet0/0
D 10.1.2.0/24 [90/2172416] via 10.1.5.1, 00:59:47, FastEthernet0/0
D 10.1.3.0/24 [90/2172416] via 10.1.5.1, 00:59:52, FastEthernet0/0
D 10.1.4.0/24 [90/2172416] via 10.1.5.1, 00:59:52, FastEthernet0/0
C 10.1.5.0/24 is directly connected, FastEthernet0/0
L 10.1.5.2/32 is directly connected, FastEthernet0/0
172.16.0.0/16 is variably subnetted, 2 subnets, 2 masks
C 172.16.10.0/24 is directly connected, Dot11Radio0/0/0
L 172.16.10.1/32 is directly connected, Dot11Radio0/0/0
D 192.168.10.0/24 [90/2174976] via 10.1.5.1, 00:59:47, FastEthernet0/0
D 192.168.20.0/24 [90/2174976] via 10.1.5.1, 00:59:47, FastEthernet0/0
D 192.168.30.0/24 [90/2174976] via 10.1.5.1, 00:59:46, FastEthernet0/0
D 192.168.40.0/24 [90/2174976] via 10.1.5.1, 00:59:46, FastEthernet0/0
S* 0.0.0.0/0 [1/0] via 10.1.5.1
Observations:
Since this is a 15.1 router, we always get a "L" local route when
we have a "C" connected route. In R3's case, the 172.16.10.0 network
is directly connected. The interface which connects it, 172.16.10.1,
counts as a "local" route. This is NOT the case on the 12.4 routers.
looking to the left, our protocol output tells us two key facts for both EIGRP and RIP:
Routing for networks:
10.0.0.0
172.16.0.0
R3 is responsible for *sending* data about these two networks to our other EIGRP routers...
"I'm R3 and I can connect you to networks on the R3
router or networks on the Corp router"
Notice how the 192 networks arent listed. R3 isnt connected to a 192 network directly, nor is it connected to a neighbor who is directly connected.
If I, as a client, am sending data to a 192 network from the 172 network, I will start
at R3. Since R3 is receiving routes for the 192 networks via Corp, I will be able to reach a 192 network via Corp.
My connection to corp will happen VIA a "10.0.0.0" route.
R3 is technically only routing for 172 and 10 networks. Beyond that, it could potentially connect to many other different networks. But in terms of the R3 routing table,
all it can offer is a path out to the 172 network or the 10 network
Routing information sources:
10.1.5.1
In this case I can see that R3 is receiving routing data from one interface only,
and that is it's link to Corp. Some of the data we are receiving from Corp actually originates
at other routers, but we cant see that here; the data comes to us from Corp, and that is all we know
EIGRP TERMINOLOGY
FEASIBLE DISTANCE (FD)
the best metric among all paths, including to the next hop neighbor. You will only see the route with the lowest FD appear in the routing table
The FD is calculated by adding the reported distance from the neighbor (AD) plus the metric to that neighbor
ADVERTISED DISTANCE (AD)
the metric of a remote network as reported by a neighbor, listed second in parenthesis in toplogy table
P 192.168.20.0/24, 2 successors, FD is 2172416
via 10.1.3.2 (2172416/28160), Serial0/0/1
feasible / advertised
Neighbor Table
each router keeps state information about adjacent neighbors.. When a new neighbor is learned, the address and interface are recorded.
The neighbor table is stored in RAM.
Sequence numbres are used to match acks with update packets. The last squence number received from a neighbor is recorded so out of order packets
can be detected
Topology Table
acted upon by DUAL Diffusing Update Alogorithm. Contains all destinations advertised by neighboring routers.
For each neighbor, the adversited distance, which comes only from that neighbor's routing table, is recorded
The feasible distance is also recorded.
Feasible Successor
a PATH whose advertised distance is less than the feasible distance of the current succesor, and is considered a backup route.
EIGRP keeps up to 16 feasible successors in the toplogy table.
The one with the best metric (The Successor) is copied and placed into the routing table
Successor
the best route to a remote network, used by EIGRP to forward traffic. It's backed up by a feasible successor, if one is available.
lets demo some more of the commands
VERIFYING EIGRP
several commands available to verify and troubleshoot
show ip route
show the entire routing table
show ip route eigrp
show only EIGRP entries in the routing table
show ip eigrp neighbors
show all EIGRP neigbors
show ip eigrp topology
show entries in the EIGRP topology table
show ip protocols
shows routing protocols configuration
debug eigrp packet
shows hello packets sent/received between adjacent routers
debug ip eigrp events
shows EIGRP changes and updates as they occur on your network
Corp#
show ip eigrp ?
interfaces IP-EIGRP interfaces
neighbors IP-EIGRP neighbors
topology IP-EIGRP Topology Table
traffic IP-EIGRP Traffic Statistics
Corp#
show ip eigrp topology
IP-EIGRP Topology Table for AS 10/ID(10.1.5.1)
Codes: P - Passive, A - Active, U - Update, Q - Query, R - Reply,
r - Reply status
P 10.1.1.0/24, 1 successors, FD is 25625600
via Connected, Vlan1
P 10.1.2.0/24, 1 successors, FD is 2169856
via Connected, Serial0/0/0
P 10.1.3.0/24, 1 successors, FD is 2169856
via Connected, Serial0/0/1
P 10.1.4.0/24, 1 successors, FD is 2169856
via Connected, Serial0/1/0
P 10.1.5.0/24, 1 successors, FD is 28160
via Connected, FastEthernet0/0
P 172.16.10.0/24, 1 successors, FD is 28160
via 10.1.5.2 (28160/25600), FastEthernet0/0
P 192.168.10.0/24, 2 successors, FD is 2172416
via 10.1.3.2 (2172416/28160), Serial0/0/1
via 10.1.2.2 (2172416/28160), Serial0/0/0
P 192.168.20.0/24, 2 successors, FD is 2172416
via 10.1.3.2 (2172416/28160), Serial0/0/1
via 10.1.2.2 (2172416/28160), Serial0/0/0
P 192.168.30.0/24, 1 successors, FD is 2172416
via 10.1.4.2 (2172416/28160), Serial0/1/0
P 192.168.40.0/24, 1 successors, FD is 2172416
via 10.1.4.2 (2172416/28160), Serial0/1/0
the "P" preceding each entry is for PASSIVE
these routes are in a passive state, which is good
if they move to an ACTIVE state, it means the have lost their path in the network and looking for a replacement.
Each entry also shows the FEASIBLE DISTANCE, the next hop address, and the local egress interface
Corp#
show ip eigrp neighbors
IP-EIGRP neighbors for process 10
H Address Interface Hold Uptime SRTT RTO Q Seq
(sec) (ms) Cnt Num
0 10.1.5.2 Fa0/0 14 02:00:05 40 1000 0 19
1 10.1.3.2 Se0/0/1 13 01:59:59 40 1000 0 14
2 10.1.2.2 Se0/0/0 13 01:59:59 40 1000 0 13
3 10.1.4.2 Se0/1/0 12 01:59:57 40 1000 0 15
fields:
H - the order in which the neighbors were discovered
hold - how long the router will wait for a hello packet
uptime - how long the neigborship has been established
SRTT - smooth round trip timer - the time it takes for a round trip from this router, to neighbor, and back.
SRTT is used to determine how long to wait for a MULTICAST reply.
if a reply isnt received in time, the router switches to UNICASTS
RTO - Retransmission Time Out- is the time EIGRP waits before retransmitting a packet from the retransmission queue
Q - indicates wheter there are oustanding messages in the queue
Seq - indicates the sequence number of the last update from that neighbor. This is used to maintain syncrhonization and avoid duplicate
or out-of-sequence processing of messages
Corp#
show ip route eigrp
172.16.0.0/24 is subnetted, 1 subnets
D 172.16.10.0 [90/28160] via 10.1.5.2, 02:08:04, FastEthernet0/0
D 192.168.10.0/24 [90/2172416] via 10.1.3.2, 02:07:59, Serial0/0/1
[90/2172416] via 10.1.2.2, 02:07:59, Serial0/0/0
D 192.168.20.0/24 [90/2172416] via 10.1.3.2, 02:07:59, Serial0/0/1
[90/2172416] via 10.1.2.2, 02:07:59, Serial0/0/0
D 192.168.30.0/24 [90/2172416] via 10.1.4.2, 02:07:58, Serial0/1/0
D 192.168.40.0/24 [90/2172416] via 10.1.4.2, 02:07:58, Serial0/1/0
Corp#
show ip eigrp interfaces
IP-EIGRP interfaces for process 10
Xmit Queue Mean Pacing Time Multicast Pending
Interface Peers Un/Reliable SRTT Un/Reliable Flow Timer Routes
Vlan 0 0/0 1236 0/10 0 0
Fa0/0 1 0/0 1236 0/10 0 0
Se0/1/0 1 0/0 1236 0/10 0 0
Se0/0/1 1 0/0 1236 0/10 0 0
Se0/0/0 1 0/0 1236 0/10 0 0
Corp#
show ip protocols
Routing Protocol is "eigrp 10 "
Outgoing update filter list for all interfaces is not set
Incoming update filter list for all interfaces is not set
Default networks flagged in outgoing updates
Default networks accepted from incoming updates
Redistributing: eigrp 10
EIGRP-IPv4 Protocol for AS(10)
Metric weight K1=1, K2=0, K3=1, K4=0, K5=0 using K1 bandwidth and K2 delay by default
NSF-aware route hold timer is 240
Router-ID: 10.1.1.1
Topology : 0 (base)
Active Timer: 3 min
Distance: internal 90 external 170
Maximum path: 4
Maximum hopcount 100
Maximum metric variance 1
Automatic Summarization: disabled
Automatic address summarization:
Maximum path: 4
Routing for Networks:
10.0.0.0
Routing Information Sources:
Gateway Distance Last Update
10.1.5.2 90 0
10.1.3.2 90 8936
10.1.4.2 90 9511
10.1.2.2 90 9597
Distance: internal 90 external 170
Routing Protocol is "rip"
Sending updates every 30 seconds, next due in 13 seconds
Invalid after 180 seconds, hold down 180, flushed after 240
Outgoing update filter list for all interfaces is not set
Incoming update filter list for all interfaces is not set
Redistributing: rip
Default version control: send version 2, receive 2
Interface Send Recv Triggered RIP Key-chain
Vlan1 2 2
FastEthernet0/0 2 2
Serial0/0/1 2 2
Serial0/1/0 2 2
Serial0/0/0 2 2
Automatic network summarization is not in effect
Maximum path: 4
Routing for Networks:
10.0.0.0
Passive Interface(s):
Routing Information Sources:
Gateway Distance Last Update
10.1.5.2 120 00:00:05
10.1.3.2 120 00:00:12
10.1.2.2 120 00:00:12
10.1.4.2 120 00:00:17
Distance: (default is 120)
corp#
debug eigrp packet
break into two columns for readability
Observations:
There doesnt appear to be a pattern in the order each router is addressed, except that the TO's and FROM"s are grouped together
The TO messages dont show the destination IP, only the egress local interface
The FROM messages do show the remote IP, as well as the local ingress interface
Corp#
EIGRP: Received HELLO on FastEthernet0/0 nbr 10.1.5.2
AS 10, Flags 0x0, Seq 18/0 idbQ 0/0
hello from R3
Corp#
EIGRP: Received HELLO on Serial0/1/0 nbr 10.1.4.2
AS 10, Flags 0x0, Seq 16/0 idbQ 0/0
hello from R2
Corp#
EIGRP: Received HELLO on Serial0/0/0 nbr 10.1.2.2
AS 10, Flags 0x0, Seq 19/0 idbQ 0/0
hello from R1
------------------------------------------------------------
Corp#
EIGRP: Sending HELLO on Serial0/1/0
AS 10, Flags 0x0, Seq 21/0 idbQ 0/0 iidbQ un/rely 0/0
hello to R2
Corp#
EIGRP: Sending HELLO on FastEthernet0/0
AS 10, Flags 0x0, Seq 21/0 idbQ 0/0 iidbQ un/rely 0/0
hello to R3
Corp#
EIGRP: Sending HELLO on Serial0/0/1
AS 10, Flags 0x0, Seq 21/0 idbQ 0/0 iidbQ un/rely 0/0
hello to R1
Corp#
EIGRP: Sending HELLO on Serial0/0/0
AS 10, Flags 0x0, Seq 21/0 idbQ 0/0 iidbQ un/rely 0/0
hello to R1
Corp#
EIGRP: Sending HELLO on Vlan1
AS 10, Flags 0x0, Seq 21/0 idbQ 0/0 iidbQ un/rely 0/0
hello to switch card (not a router....)
------------------------------------------------------------
Corp#
EIGRP: Received HELLO on Serial0/0/1 nbr 10.1.3.2
AS 10, Flags 0x0, Seq 19/0 idbQ 0/0
hello from R1
Corp#
EIGRP: Received HELLO on FastEthernet0/0 nbr 10.1.5.2
AS 10, Flags 0x0, Seq 18/0 idbQ 0/0
hello from R3
Corp#
EIGRP: Received HELLO on Serial0/0/0 nbr 10.1.2.2
AS 10, Flags 0x0, Seq 19/0 idbQ 0/0
hello from R1
Corp#
EIGRP: Received HELLO on Serial0/1/0 nbr 10.1.4.2
AS 10, Flags 0x0, Seq 16/0 idbQ 0/0
hello from R2
------------------------------------------------------------
Corp#
EIGRP: Sending HELLO on Serial0/1/0
AS 10, Flags 0x0, Seq 21/0 idbQ 0/0 iidbQ un/rely 0/0
hello to R2... no neighbor IP?
Corp#
EIGRP: Sending HELLO on Serial0/0/0
AS 10, Flags 0x0, Seq 21/0 idbQ 0/0 iidbQ un/rely 0/0
hello to R1... no neighbor IP?
Corp#
EIGRP: Sending HELLO on FastEthernet0/0
AS 10, Flags 0x0, Seq 21/0 idbQ 0/0 iidbQ un/rely 0/0
hello to R3... no neighbor IP?
Corp#
EIGRP: Sending HELLO on Serial0/0/1
AS 10, Flags 0x0, Seq 21/0 idbQ 0/0 iidbQ un/rely 0/0
hello to R1
Corp#
EIGRP: Sending HELLO on Vlan1
AS 10, Flags 0x0, Seq 21/0 idbQ 0/0 iidbQ un/rely 0/0
hello to switch card (not a router)
------------------------------------------------------------
OUTPUT CONTINUES IN NEXT COLUMN
Corp#
EIGRP: Received HELLO on Serial0/0/1 nbr 10.1.3.2
AS 10, Flags 0x0, Seq 19/0 idbQ 0/0
hello from R1
Corp#
EIGRP: Received HELLO on FastEthernet0/0 nbr 10.1.5.2
AS 10, Flags 0x0, Seq 18/0 idbQ 0/0
hello from R3
Corp#
EIGRP: Received HELLO on Serial0/0/0 nbr 10.1.2.2
AS 10, Flags 0x0, Seq 19/0 idbQ 0/0
hello from R1
Corp#
EIGRP: Received HELLO on Serial0/1/0 nbr 10.1.4.2
AS 10, Flags 0x0, Seq 16/0 idbQ 0/0
hello from R2
------------------------------------------------------------
Corp#
EIGRP: Sending HELLO on Serial0/1/0
AS 10, Flags 0x0, Seq 21/0 idbQ 0/0 iidbQ un/rely 0/0
hello to R2
Corp#
EIGRP: Sending HELLO on Serial0/0/0
AS 10, Flags 0x0, Seq 21/0 idbQ 0/0 iidbQ un/rely 0/0
hello to R1
Corp#
EIGRP: Sending HELLO on Vlan1
AS 10, Flags 0x0, Seq 21/0 idbQ 0/0 iidbQ un/rely 0/0
hello to Corp switchcard
Corp#
EIGRP: Sending HELLO on Serial0/0/1
AS 10, Flags 0x0, Seq 21/0 idbQ 0/0 iidbQ un/rely 0/0
hello to R1
Corp#
EIGRP: Sending HELLO on FastEthernet0/0
AS 10, Flags 0x0, Seq 21/0 idbQ 0/0 iidbQ un/rely 0/0
hello to R3... no neighbor IP?
------------------------------------------------------------
Corp#
EIGRP: Received HELLO on Serial0/0/1 nbr 10.1.3.2
AS 10, Flags 0x0, Seq 19/0 idbQ 0/0
hello from R1
Corp#
EIGRP: Received HELLO on FastEthernet0/0 nbr 10.1.5.2
AS 10, Flags 0x0, Seq 18/0 idbQ 0/0
hello from R3
Corp#
EIGRP: Received HELLO on Serial0/1/0 nbr 10.1.4.2
AS 10, Flags 0x0, Seq 16/0 idbQ 0/0
hello from R2
Corp#
EIGRP: Received HELLO on Serial0/0/0 nbr 10.1.2.2
AS 10, Flags 0x0, Seq 19/0 idbQ 0/0
hello from R1
------------------------------------------------------------
Corp#
EIGRP: Sending HELLO on Serial0/1/0
AS 10, Flags 0x0, Seq 21/0 idbQ 0/0 iidbQ un/rely 0/0
hello to R2
Corp#
EIGRP: Sending HELLO on Vlan1
AS 10, Flags 0x0, Seq 21/0 idbQ 0/0 iidbQ un/rely 0/0
hello to Corp switchcard
EIGRP: Sending HELLO on Serial0/0/0
AS 10, Flags 0x0, Seq 21/0 idbQ 0/0 iidbQ un/rely 0/0
hello to R1
EIGRP: Sending HELLO on Serial0/0/1
AS 10, Flags 0x0, Seq 21/0 idbQ 0/0 iidbQ un/rely 0/0
hello to R1
Corp#
EIGRP: Sending HELLO on FastEthernet0/0
AS 10, Flags 0x0, Seq 21/0 idbQ 0/0 iidbQ un/rely 0/0
hello to R3
------------------------------------------------------------
Now some videos. To reinforce EIGRP concepts, and lead into OSPF
OSPF - OPEN SHORTEST PATH FIRST
Before enabling OSPF, we'll turn off RIP and EIGRP on all four routers.
Device(config)#
no router eigrp 10
Device(config)#
no router rip
The OSPF configs for the local egress ip address
Corp(config)#
router ospf 132
Corp(config)#
network 10.1.0.0 0.0.255.255 area 0
R1(config)#
router ospf 1
R1(config)#
network 10.1.0.0 0.0.255.255 area 0
R1(config)#
network 192.168.0.0 0.0.255.255 area 0
R2(config)#
router ospf 45678
R2(config)#
network 10.0.0.0 0.0.0.255 area 0
R2(config)#
network 192.168.30.1 0.0.0.0 area 0
R2(config)#
network 192.168.40.1 0.0.0.0 area 0
all 32 bits of the mask are specified for the 192 entries;
these are not network id's, they are HOST id's of the specific interfaces, which are EGRESS interfaces on the router we are configuring
R3(config)#
router ospf 1
R2(config)#
network 10.1.5.2 0.0.0.255 area 0
R2(config)#
network 172.16.10.0 0.0.0.255 area 0
Wildcard Masks
these notes are not intended to be a precise explanation of wlidcard masking, but rather a look into my thought process as I am learning the concept.
resources:
traceroute blog examples
routerjockey blog examples
subnetonline wildcard calculator
Ch 9 Exam Essentials
1. Know EIGRP features
classless (like RipV2 and OSPF)
distance vector
supports IP, IPX, appleTalk, IPV6
supports summaries and discontiguous networks
uses the Diffusing Update Algorithm (DUAL) to maintain route information
uses RTP to communicate with other EIGRP routers
uses the concept of an autonomous system to describe the set of contiguous routers that run the same routing protocol and share routing information
considered CLASSLESS- includes the subnet mask in its route updates
sends traditional distance-vector updates containing info about networks plus the cost of reaching them from the perspective of the advertising router
but not strictly distance-vector. Has link-state characteristics: synchronizes routing tables between neighbors at startup and then sends specific updates only when topology changes.
max hop count of 255 (default is 100)
but hop count is NOT a metric, like in RIP. Hop count is how many routers an EIGRP route update can traverse before being discarded. This limits the size of the AS.
2. Know how to configure EIGRP
the router eigrp [as] command turns EIGRP routing on in the router. Unlike RIPv1, EIGRP uses classless routing. BUT you can still configure as classful.
R1(config)#
router eigrp 10
enters router config mode
R1(config-router)#
network 10.0.0.0
on this router, interfaces that fall within 10.0.0.0 will advertise EIGRP info
3. Know how to verify EIGRP operation
Corp#
show ip
protocols
Corp#
show ip
route
Corp#
show ip
route eigrp
Corp#
show ip
eigrp neighbors
Corp#
show ip
eigrp topology
Corp#
show ip
eigrp interfaces
Corp#
show ip
protocols
info about all active routing protocols
Routing Protocol is "eigrp 10 "
Outgoing update filter list for all interfaces is not set
Incoming update filter list for all interfaces is not set
Default networks flagged in outgoing updates
Default networks accepted from incoming updates
Redistributing: eigrp 10
EIGRP-IPv4 Protocol for AS(10)
Metric weight K1=1, K2=0, K3=1, K4=0, K5=0
NSF-aware route hold timer is 240
Router-ID: 10.1.1.1
Topology : 0 (base)
Active Timer: 3 min
Distance: internal 90 external 170
Maximum path: 4
Maximum hopcount 100
Maximum metric variance 1
Automatic Summarization: disabled
Automatic address summarization:
Maximum path: 4
Routing for Networks:
10.0.0.0
Routing Information Sources:
Gateway Distance Last Update
10.1.2.2 90 200105
10.1.3.2 90 200113
10.1.4.2 90 254351
10.1.5.2 90 303742
Distance: internal 90 external 170
Corp#
show ip
protocols
(continued)
Routing Protocol is "rip"
Sending updates every 30 seconds, next due in 6 seconds
Invalid after 180 seconds, hold down 180, flushed after 240
Outgoing update filter list for all interfaces is not set
Incoming update filter list for all interfaces is not set
Redistributing: rip
Default version control: send version 2, receive 2
Interface Send Recv Triggered RIP Key-chain
Vlan1 2 2
FastEthernet0/0 2 2
Serial0/1/0 2 2
Serial0/0/1 2 2
Serial0/0/0 2 2
Automatic network summarization is not in effect
Maximum path: 4
Routing for Networks:
10.0.0.0
Passive Interface(s):
Routing Information Sources:
Gateway Distance Last Update
10.1.5.2 120 00:00:15
10.1.3.2 120 00:00:01
10.1.2.2 120 00:00:01
10.1.4.2 120 00:00:17
Distance: (default is 120)
Corp#
show ip
route
entire routing table
Codes: L - local, C - connected, S - static, R - RIP, M - mobile, B - BGP
D - EIGRP, EX - EIGRP external, O - OSPF, IA - OSPF inter area
N1 - OSPF NSSA external type 1, N2 - OSPF NSSA external type 2
E1 - OSPF external type 1, E2 - OSPF external type 2, E - EGP
i - IS-IS, L1 - IS-IS level-1, L2 - IS-IS level-2, ia - IS-IS inter area
* - candidate default, U - per-user static route, o - ODR
P - periodic downloaded static route
Gateway of last resort is not set
10.0.0.0/8 is variably subnetted, 10 subnets, 2 masks
C 10.1.1.0/24 is directly connected, Vlan1
L 10.1.1.1/32 is directly connected, Vlan1
C 10.1.2.0/24 is directly connected, Serial0/0/0
L 10.1.2.1/32 is directly connected, Serial0/0/0
C 10.1.3.0/24 is directly connected, Serial0/0/1
L 10.1.3.1/32 is directly connected, Serial0/0/1
C 10.1.4.0/24 is directly connected, Serial0/1/0
L 10.1.4.1/32 is directly connected, Serial0/1/0
C 10.1.5.0/24 is directly connected, FastEthernet0/0
L 10.1.5.1/32 is directly connected, FastEthernet0/0
172.16.0.0/16 is variably subnetted, 2 subnets, 2 masks
R 172.16.0.0/16 [120/1] via 10.1.5.2, 00:00:14, FastEthernet0/0
D 172.16.10.0/24 [90/28160] via 10.1.5.2, 00:07:23, FastEthernet0/0
D 192.168.10.0/24 [90/2172416] via 10.1.3.2, 00:09:13, Serial0/0/1
[90/2172416] via 10.1.2.2, 00:09:13, Serial0/0/0
D 192.168.20.0/24 [90/2172416] via 10.1.3.2, 00:09:13, Serial0/0/1
[90/2172416] via 10.1.2.2, 00:09:13, Serial0/0/0
D 192.168.30.0/24 [90/2172416] via 10.1.4.2, 00:08:59, Serial0/1/0
D 192.168.40.0/24 [90/2172416] via 10.1.4.2, 00:08:59, Serial0/1/0
Shows the entire routing table
Corp#
show ip
eigrp toplogy
all nets the Corp router can see, including on the other side of other routers
IP-EIGRP Topology Table for AS 10/ID(10.1.5.1)
Codes: P - Passive, A - Active, U - Update, Q - Query, R - Reply,
r - Reply status
directly connected via local egress interface
P 10.1.1.0/24, 1 successors, FD is 25625600
via Connected, Vlan1
P 10.1.2.0/24, 1 successors, FD is 2169856
via Connected, Serial0/0/0
P 10.1.3.0/24, 1 successors, FD is 2169856
via Connected, Serial0/0/1
P 10.1.4.0/24, 1 successors, FD is 2169856
via Connected, Serial0/1/0
P 10.1.5.0/24, 1 successors, FD is 28160
via Connected, FastEthernet0/0
remotely connected via remote ingress ip address
P 172.16.10.0/24, 1 successors, FD is 28160
via 10.1.5.2 (28160/25600), FastEthernet0/0
P 192.168.10.0/24, 2 successors, FD is 2172416
via 10.1.3.2 (2172416/28160), Serial0/0/1
via 10.1.2.2 (2172416/28160), Serial0/0/0
P 192.168.20.0/24, 2 successors, FD is 2172416
via 10.1.3.2 (2172416/28160), Serial0/0/1
via 10.1.2.2 (2172416/28160), Serial0/0/0
P 192.168.30.0/24, 1 successors, FD is 2172416
via 10.1.4.2 (2172416/28160), Serial0/1/0
P 192.168.40.0/24, 1 successors, FD is 2172416
via 10.1.4.2 (2172416/28160), Serial0/1/0
Corp#
show ip
eigrp interfaces
local interfaces on Corp, with peer data, 5 total, including VLAN1 (0 peers, no router on this network)
IP-EIGRP interfaces for process 10
Xmit Queue Mean Pacing Time Multicast Pending
Interface Peers Un/Reliable SRTT Un/Reliable Flow Timer Routes
Vlan 0 0/0 1236 0/10 0 0
Fa0/0 1 0/0 1236 0/10 0 0
Se0/0/1 1 0/0 1236 0/10 0 0
Se0/1/0 1 0/0 1236 0/10 0 0
Se0/0/0 1 0/0 1236 0/10 0 0
Corp#
show ip
eigrp neighbors
remote interfaces on the 4 neighboring routers
IP-EIGRP neighbors for process 10
H Address Interface Hold Uptime SRTT RTO Q Seq
(sec) (ms) Cnt Num
0 10.1.2.2 Se0/0/0 14 00:54:33 40 1000 0 58
1 10.1.3.2 Se0/0/1 10 00:54:33 40 1000 0 57
2 10.1.4.2 Se0/1/0 14 00:53:38 40 1000 0 51
3 10.1.5.2 Fa0/0 11 00:52:49 40 1000 0 33
4. Compare OSPF and RIPv1
RIPv1 is distance-vector and supports only classful routing. No VLSM
OSPF is link-state and supports VLSM and classless routing
5. Know how OSPF routers become neighboars and/or adjacent
they become neighbors when they see eachother's hello packets.
area id must match, links must be on the same subnet, hello/dead timers must be the same.
OSPF only shares routes with neigbors who have also established adjacencies. NOT ALL NEIGHBORS become adjacent.
When an OSPF router first receives a hello packet, it verifies that the data in some fields matches its own locally configured information.
Should any of the checked data be different, the hello packet is discarded and not processed. The data fields verified are the Area ID,
Authentication, Network Mask (on broadcast networks), Hello Interval, Router Dead Interval, and Options fields. If this information doesn’t match,
then neighborship is stuck in the down stage.
packetpushers.net
6. Be able to configure single-area OSPF
two commands:
router ospf [process id]
network x.x.x.x y.y.y.y area z
7. Be able to verify the operation of OSPF
Corp#
show ip
protocols
Corp#
show ip
route
Corp#
show ip
ospf
Corp#
show ip
ospf database
Corp#
show ip
ospf interface
Corp#
show ip
ospf neighbor
IOS 15.1
Corp#
show ip
protocols
Routing Protocol is "ospf 132"
Outgoing update filter list for all interfaces is not set
Incoming update filter list for all interfaces is not set
Router ID 10.1.5.1
Number of areas in this router is 1. 1 normal 0 stub 0 nssa
Maximum path: 4
Routing for Networks:
10.1.0.0 0.0.255.255 area 0
Routing Information Sources:
Gateway Distance Last Update
10.1.5.1 110 00:08:51
172.16.10.1 110 00:08:51
192.168.20.1 110 00:12:53
192.168.40.1 110 00:09:35
Distance: (default is 110)
IOS 15.1
Corp#
show ip
route
10.0.0.0/8 is variably subnetted, 10 subnets, 2 masks
C 10.1.1.0/24 is directly connected, Vlan1
L 10.1.1.1/32 is directly connected, Vlan1
C 10.1.2.0/24 is directly connected, Serial0/0/0
L 10.1.2.1/32 is directly connected, Serial0/0/0
C 10.1.3.0/24 is directly connected, Serial0/0/1
L 10.1.3.1/32 is directly connected, Serial0/0/1
C 10.1.4.0/24 is directly connected, Serial0/1/0
L 10.1.4.1/32 is directly connected, Serial0/1/0
C 10.1.5.0/24 is directly connected, FastEthernet0/0
L 10.1.5.1/32 is directly connected, FastEthernet0/0
172.16.0.0/24 is subnetted, 1 subnets
O 172.16.10.0/24 [110/10] via 10.1.5.2, 00:09:09, FastEthernet0/0
O 192.168.10.0/24 [110/65] via 10.1.2.2, 00:13:11, Serial0/0/0
O 192.168.20.0/24 [110/65] via 10.1.2.2, 00:13:01, Serial0/0/0
O 192.168.30.0/24 [110/65] via 10.1.4.2, 00:09:54, Serial0/1/0
O 192.168.40.0/24 [110/65] via 10.1.4.2, 00:09:54, Serial0/1/0
IOS 15.1
Corp#
show ip
ospf
Routing Process "ospf 132" with ID 10.1.5.1
Supports only single TOS(TOS0) routes
Supports opaque LSA
SPF schedule delay 5 secs, Hold time between two SPFs 10 secs
Minimum LSA interval 5 secs. Minimum LSA arrival 1 secs
Number of external LSA 0. Checksum Sum 0x000000
Number of opaque AS LSA 0. Checksum Sum 0x000000
Number of DCbitless external and opaque AS LSA 0
Number of DoNotAge external and opaque AS LSA 0
Number of areas in this router is 1. 1 normal 0 stub 0 nssa
External flood list length 0
Area BACKBONE(0)
Number of interfaces in this area is 5
Area has no authentication
SPF algorithm executed 7 times
Area ranges are
Number of LSA 5. Checksum Sum 0x034486
Number of opaque link LSA 0. Checksum Sum 0x000000
Number of DCbitless LSA 0
Number of indication LSA 0
Number of DoNotAge LSA 0
Flood list length 0
IOS 15.1
Corp#
show ip
ospf database
OSPF Router with ID (10.1.5.1) (Process ID 132)
Router Link States (Area 0)
Link ID ADV Router Age Seq# Checksum Link count
192.168.20.1 192.168.20.1 854 0x80000006 0x00ae08 6
192.168.40.1 192.168.40.1 656 0x80000004 0x006bc6 4
10.1.5.1 10.1.5.1 612 0x8000000f 0x00ab77 8
172.16.10.1 172.16.10.1 612 0x80000003 0x00b30d 2
Net Link States (Area 0)
Link ID ADV Router Age Seq# Checksum
10.1.5.1 10.1.5.1 612 0x80000001 0x00cc34
ADV Router aka RID/Router ID, the highest IP address on the router
we are seeing three connected routers + our own router (Corp at 10.1.5.1)
IOS 15.1
Corp#
show ip
ospf interface
Vlan1 is up, line protocol is up
Internet address is 10.1.1.1/24, Area 0
Process ID 132, Router ID 10.1.5.1, Network Type BROADCAST, Cost: 1
Transmit Delay is 1 sec, State DR, Priority 1
Designated Router (ID) 10.1.5.1, Interface address 10.1.1.1
No backup designated router on this network
Timer intervals configured, Hello 10, Dead 40, Wait 40, Retransmit 5
Hello due in 00:00:08
Index 1/1, flood queue length 0
Next 0x0(0)/0x0(0)
Last flood scan length is 1, maximum is 1
Last flood scan time is 0 msec, maximum is 0 msec
Neighbor Count is 0, Adjacent neighbor count is 0
Suppress hello for 0 neighbor(s)
FastEthernet0/0 is up, line protocol is up
Internet address is 10.1.5.1/24, Area 0
Process ID 132, Router ID 10.1.5.1, Network Type BROADCAST, Cost: 1
Transmit Delay is 1 sec, State DR, Priority 1
Designated Router (ID) 10.1.5.1, Interface address 10.1.5.1
Backup Designated Router (ID) 172.16.10.1, Interface address 10.1.5.2
Timer intervals configured, Hello 10, Dead 40, Wait 40, Retransmit 5
Hello due in 00:00:07
Index 2/2, flood queue length 0
Next 0x0(0)/0x0(0)
Last flood scan length is 1, maximum is 1
Last flood scan time is 0 msec, maximum is 0 msec
Neighbor Count is 1, Adjacent neighbor count is 1
Adjacent with neighbor 172.16.10.1 (Backup Designated Router)
Suppress hello for 0 neighbor(s)
Serial0/0/1 is up, line protocol is up
Internet address is 10.1.3.1/24, Area 0
Process ID 132, Router ID 10.1.5.1, Network Type POINT-TO-POINT, Cost: 64
Transmit Delay is 1 sec, State POINT-TO-POINT,
Timer intervals configured, Hello 10, Dead 40, Wait 40, Retransmit 5
Hello due in 00:00:07
Index 3/3, flood queue length 0
Next 0x0(0)/0x0(0)
Last flood scan length is 1, maximum is 1
Last flood scan time is 0 msec, maximum is 0 msec
Neighbor Count is 1 , Adjacent neighbor count is 1
Adjacent with neighbor 192.168.20.1
Suppress hello for 0 neighbor(s)
Serial0/1/0 is up, line protocol is up
Internet address is 10.1.4.1/24, Area 0
Process ID 132, Router ID 10.1.5.1, Network Type POINT-TO-POINT, Cost: 64
Transmit Delay is 1 sec, State POINT-TO-POINT,
Timer intervals configured, Hello 10, Dead 40, Wait 40, Retransmit 5
Hello due in 00:00:07
Index 4/4, flood queue length 0
Next 0x0(0)/0x0(0)
Last flood scan length is 1, maximum is 1
Last flood scan time is 0 msec, maximum is 0 msec
Neighbor Count is 1 , Adjacent neighbor count is 1
Adjacent with neighbor 192.168.40.1
Suppress hello for 0 neighbor(s)
Serial0/0/0 is up, line protocol is up
Internet address is 10.1.2.1/24, Area 0
Process ID 132, Router ID 10.1.5.1, Network Type POINT-TO-POINT, Cost: 64
Transmit Delay is 1 sec, State POINT-TO-POINT,
Timer intervals configured, Hello 10, Dead 40, Wait 40, Retransmit 5
Hello due in 00:00:07
Index 5/5, flood queue length 0
Next 0x0(0)/0x0(0)
Last flood scan length is 1, maximum is 1
Last flood scan time is 0 msec, maximum is 0 msec
Neighbor Count is 1 , Adjacent neighbor count is 1
Adjacent with neighbor 192.168.20.1
Suppress hello for 0 neighbor(s)
IOS 15.1
Corp#
show ip
ospf neighbor
Neighbor ID Pri State Dead Time Address Interface
192.168.20.1 0 FULL/ - 00:00:31 10.1.3.2 Serial0/0/1
192.168.40.1 0 FULL/ - 00:00:33 10.1.4.2 Serial0/1/0
192.168.20.1 0 FULL/ - 00:00:31 10.1.2.2 Serial0/0/0
172.16.10.1 1 FULL/BDR 00:00:32 10.1.5.2 FastEthernet0/0
Flashcards
Chapter 9 Written Lab 9.0
1. What four routed protocols are supported by EIGRP?
IPX, IPv4, IPv6, AppleTalk
2. When is redistribution required for EIGRP?
when there are multiple autonomous systems
redistribution is required when more than one EIGRP session or process is running and they are identified with different ASNs.
redistribution shares toplogy information between EIGRP sessions
3. What command would be used to enable EIGRP with an autonmous system number of 300?
router eigrp 300
4. What command will tell EIGRP that it is connected to network 172.10.0.0?
network 172.10.0.0
5. What type of EIGRP interface will neither send nor receive Hello packets?
passive-interface s0/0
6. Write the command that will enable OSPF process 101 on a router
router ospf 101
7. Write the command that will display details of all OSFP routing processes enabled on a router
show ip ospf
8. Write the command that will display interface-specific OSPF information
show ip ospf interface
9. Write the command that will display all OSPF neighbors
show ip ospf neighbor
10. Write the command that will display all different OSPF route types that are currently known by the router
show ip route ospf
Chapter 9 Hands-On Labs
Build the network and configure interfaces
LabA(config)#
int f0/0
LabA(config-if)#
ip addr 172.16.10.1 255.255.255.0
LabA(config-if)#
no shut
LabB(config)#
int f0/0
LabB(config-if)#
ip addr 172.16.10.2 255.255.255.0
LabB(config-if)#
no shut
LabB(config-if)#
int s0/0/0
LabB(config-if)#
ip addr 172.16.20.1 255.255.255.0
LabB(config-if)#
no shut
LabC(config)#
int f0/0
LabC(config-if)#
ip addr 172.16.30.1 255.255.255.0
LabC(config-if)#
no shut
LabC(config-if)#
int s0/0/0
LabC(config-if)#
ip addr 172.16.20.2 255.255.255.0
LabC(config-if)#
no shut
LabC(config-if)#
int s0/0/1
LabC(config-if)#
ip addr 172.16.40.1 255.255.255.0
LabC(config-if)#
no shut
LabD(config)#
int s0/0/0
LabD(config-if)#
ip addr 172.16.40.2 255.255.255.0
LabD(config-if)#
no shut
LabD(config-if)#
int f0/0
LabD(config-if)#
ip addr 172.16.50.1 255.255.255.0
LabD(config-if)#
no shut
9.1 - Configure and Verfiy EIGRP
configure EIGRP on all 4 routers and observe results
LabA
LabA(config)#
router eigrp 100
LabA(config-router)#
net 172.16.0.0
[no output]
LabA#
show ip eigrp neighbors
IP-EIGRP neighbors for process 100
LabA#
show ip eigrp topology
IP-EIGRP Topology Table for AS 100/ID(172.16.10.1)
Codes: P - Passive, A - Active, U - Update, Q - Query, R - Reply,
r - Reply status
P 172.16.10.0/24, 1 successors, FD is 28160
via Connected, FastEthernet0/0
LabA#
show ip eigrp interfaces
IP-EIGRP interfaces for process 100
Xmit Queue Mean Pacing Time Multicast Pending
Interface Peers Un/Reliable SRTT Un/Reliable Flow Timer Routes
Fa0/0 0 0/0 1236 0/10 0 0
no neighbors at this point since EIGRP is only active on this router. One successor AKA route, which is the connection out of this router.
But note that we have no information about what's on the other side of that link
LabB
LabB(config)#
router eigrp 100
LabB(config-router)#
net 172.16.0.0
%DUAL-5-NBRCHANGE: IP-EIGRP 100:
Neighbor 172.16.10.1 (FastEthernet0/0) is up: new adjacency
LabB#
show ip eigrp neighbors
IP-EIGRP neighbors for process 100
H Address Interface Hold Uptime SRTT RTO Q Seq
(sec) (ms) Cnt Num
0 172.16.10.1 Fa0/0 12 00:00:14 40 1000 0 1
LabB#
show ip eigrp topology
IP-EIGRP Topology Table for AS 100/ID(172.16.20.1)
Codes: P - Passive, A - Active, U - Update, Q - Query, R - Reply,
r - Reply status
P 172.16.10.0/24, 1 successors, FD is 28160
via Connected, FastEthernet0/0
P 172.16.20.0/24, 1 successors, FD is 2169856
via Connected, Serial0/0/0
LabB#
show ip eigrp interfaces
IP-EIGRP interfaces for process 100
Xmit Queue Mean Pacing Time Multicast Pending
Interface Peers Un/Reliable SRTT Un/Reliable Flow Timer Routes
Fa0/0 1 0/0 1236 0/10 0 0
Se0/0/0 0 0/0 1236 0/10 0 0
We can see a neighbor at .1
We now have two paths out of this router. Left to neighbor. Exit at right is available as successor(route), but again we have no info about
what is on the other side, since that router has no EIGRP yet (s0/0/0 has no peers, but is an EIGRP interface)
LabC
LabC(config)#
router eigrp 100
LabC(config-router)#
net 172.16.0.0
%DUAL-5-NBRCHANGE: IP-EIGRP 100:
Neighbor 172.16.20.1 (Serial0/0/0) is up: new adjacency
LabC#
show ip eigrp neighbors
IP-EIGRP neighbors for process 100
H Address Interface Hold Uptime SRTT RTO Q Seq
(sec) (ms) Cnt Num
0 172.16.20.1 Se0/0/0 12 00:00:25 40 1000 0 8
LabC#
show ip eigrp toplogy
IP-EIGRP Topology Table for AS 100/ID(172.16.40.1)
Codes: P - Passive, A - Active, U - Update, Q - Query, R - Reply,
r - Reply status
P 172.16.10.0/24, 1 successors, FD is 2172416
via 172.16.20.1 (2172416/28160), Serial0/0/0
P 172.16.20.0/24, 1 successors, FD is 2169856
via Connected, Serial0/0/0
P 172.16.30.0/24, 1 successors, FD is 28160
via Connected, FastEthernet0/0
P 172.16.40.0/24, 1 successors, FD is 2169856
via Connected, Serial0/0/1
LabC#
show ip eigrp interfaces
IP-EIGRP interfaces for process 100
Xmit Queue Mean Pacing Time Multicast Pending
Interface Peers Un/Reliable SRTT Un/Reliable Flow Timer Routes
Fa0/0 0 0/0 1236 0/10 0 0
Se0/0/0 1 0/0 1236 0/10 0 0
Se0/0/1 0 0/0 1236 0/10 0 0
.1 router B interface is now a neighbor.
LabC topology shows the 3 direct connected networks AND the network on the other side of LabB since LabB is our EIGRP neighbor
3 eigrp interfaces:
Fa0/0 is ours at LabC- no peers bc there is no eigrp router on the other end
s0/0/0 is our interface out left to LabB which is an EIGRP peer
s0/0/1 is our interface out right which does not see an EIGRP peer but does put that net 172.16.40.0 in our topology
LabD
LabD(config)#
router eigrp 100
LabD(config-router)#
net 172.16.0.0
%DUAL-5-NBRCHANGE: IP-EIGRP 100:
Neighbor 172.16.40.1 (Serial0/0/0) is up: new adjacency
LabD#
show ip eigrp neighbors
IP-EIGRP neighbors for process 100
H Address Interface Hold Uptime SRTT RTO Q Seq
(sec) (ms) Cnt Num
0 172.16.40.1 Se0/0/0 11 00:00:14 40 1000 0 6
LabD#
show ip eigrp topology
IP-EIGRP Topology Table for AS 100/ID(172.16.50.1)
Codes: P - Passive, A - Active, U - Update, Q - Query, R - Reply,
r - Reply status
P 172.16.10.0/24, 1 successors, FD is 2684416
via 172.16.40.1 (2684416/2172416), Serial0/0/0
P 172.16.20.0/24, 1 successors, FD is 2681856
via 172.16.40.1 (2681856/2169856), Serial0/0/0
P 172.16.30.0/24, 1 successors, FD is 2172416
via 172.16.40.1 (2172416/28160), Serial0/0/0
P 172.16.40.0/24, 1 successors, FD is 2169856
via Connected, Serial0/0/0
P 172.16.50.0/24, 1 successors, FD is 28160
via Connected, FastEthernet0/0
LabD#
show ip eigrp interfaces
IP-EIGRP interfaces for process 100
Xmit Queue Mean Pacing Time Multicast Pending
Interface Peers Un/Reliable SRTT Un/Reliable Flow Timer Routes
Fa0/0 0 0/0 1236 0/10 0 0
Se0/0/0 1 0/0 1236 0/10 0 0
LabC to our left is now a neighbor at 172.16.40.1
toplogy shows a route out to the right (no router on that end)
a route to the left to LabC .40.0
the .10.0, .20.0, and .30.0 networks via info from LabC
2 eigrp interfaces-
fa0/0 out to the right
s0/0/0 out left to LabC
Time to remove EIGRP from all four routers to prepare for the OSPF lab next,
since EIGRP has a lower AD than OSPF
LabA(config)#
no router eigrp 100
LabB(config)#
no router eigrp 100
LabC(config)#
no router eigrp 100
LabD(config)#
no router eigrp 100
9.2 - Enabling the OSPF Process
9.3 - Configuring OSPF Interfaces
9.4 - Verifying OSPF Operation
LabA
LabA(config)#
router ospf 100
LabA(config-router)#
net 172.16.10.1 0.0.0.0 area 0
[no output]
LabA#
show ip ospf neighbor
[no output]
LabA#
show ip ospf database
OSPF Router with ID (172.16.10.1) (Process ID 100)
Router Link States (Area 0)
Link ID ADV Router Age Seq# Checksum Link count
172.16.10.1 172.16.10.1 44 0x80000001 0x00b24b 1
LabA#
show ip ospf interface
FastEthernet0/0 is up, line protocol is up
Internet address is 172.16.10.1/24, Area 0
Process ID 100, Router ID 172.16.10.1, Network Type BROADCAST, Cost: 1
Transmit Delay is 1 sec, State DR, Priority 1
Designated Router (ID) 172.16.10.1, Interface address 172.16.10.1
No backup designated router on this network
Timer intervals configured, Hello 10, Dead 40, Wait 40, Retransmit 5
Hello due in 00:00:08
Index 1/1, flood queue length 0
Next 0x0(0)/0x0(0)
Last flood scan length is 1, maximum is 1
Last flood scan time is 0 msec, maximum is 0 msec
Neighbor Count is 0, Adjacent neighbor count is 0
Suppress hello for 0 neighbor(s)
we're including this router's interface 172.16.10.1 in our ospf area 0
fa0/0 now registers as an ospf interface
the ospf database includes data about this link only.... LabA is counting itself(10.1) as ADVERTISTING router?
the designated router is .1 LabA
LabB
LabB(config)#
router ospf 101
LabB(config-router)#
net 172.16.10.2 0.0.0.0 area 0
LabB(config-router)#
net 172.16.20.1 0.0.0.0 area 0
01:26:36: %OSPF-5-ADJCHG: Process 101, Nbr 172.16.10.1
on FastEthernet0/0 from LOADING to FULL, Loading Done
LabB#
show ip ospf neighbor
Neighbor ID Pri State Dead Time Address Interface
172.16.10.1 1 FULL/DR 00:00:33 172.16.10.1
LabB#
show ip ospf database
OSPF Router with ID (172.16.20.1) (Process ID 101)
Router Link States (Area 0)
Link ID ADV Router Age Seq# Checksum Link count
172.16.10.1 172.16.10.1 145 0x80000002 0x0067cd 1
172.16.20.1 172.16.20.1 32 0x80000003 0x006e8f 2
Net Link States (Area 0)
Link ID ADV Router Age Seq# Checksum
172.16.10.1 172.16.10.1 145 0x80000001 0x00953d
LabB#
show ip ospf interface
FastEthernet0/0 is up, line protocol is up
Internet address is 172.16.10.2/24, Area 0
Process ID 101, Router ID 172.16.20.1, Network Type BROADCAST, Cost: 1
Transmit Delay is 1 sec, State BDR, Priority 1
Designated Router (ID) 172.16.10.1, Interface address 172.16.10.1
Backup Designated Router (ID) 172.16.20.1, Interface address 172.16.10.2
Timer intervals configured, Hello 10, Dead 40, Wait 40, Retransmit 5
Hello due in 00:00:03
Index 1/1, flood queue length 0
Next 0x0(0)/0x0(0)
Last flood scan length is 1, maximum is 1
Last flood scan time is 0 msec, maximum is 0 msec
Neighbor Count is 1, Adjacent neighbor count is 1
Adjacent with neighbor 172.16.10.1 (Designated Router)
Suppress hello for 0 neighbor(s)
Serial0/0/0 is up, line protocol is up
Internet address is 172.16.20.1/24, Area 0
Process ID 101, Router ID 172.16.20.1, Network Type POINT-TO-POINT, Cost: 64
Transmit Delay is 1 sec, State POINT-TO-POINT,
Timer intervals configured, Hello 10, Dead 40, Wait 40, Retransmit 5
Hello due in 00:00:04
Index 2/2, flood queue length 0
Next 0x0(0)/0x0(0)
Last flood scan length is 1, maximum is 1
Last flood scan time is 0 msec, maximum is 0 msec
Suppress hello for 0 neighbor(s)
We've include the two interfaces on this router in the OSPF area
and can now see Router A's interface 10.1 to the left as a neighbor in the area
the "OSPF Database" now shows two links 20.1(local) and 10.1(neighbor) as 'router link states'.
"ADV Router" means advertising router for the two links. The link address is used as the advertising router.
database shows "Net Link States" category with one entry- 172.16.10.1 which is the address of neighbor router to our left
we have two local OSPF interfaces- f0/0 and s0/0/0
LabC
LabC(config)#
router ospf 102
LabC(config-router)#
net 172.16.20.2 0.0.0.0 area 0
LabC(config-router)#
net 172.16.30.1 0.0.0.0 area 0
LabC(config-router)#
net 172.16.40.1 0.0.0.0 area 0
01:33:54: %OSPF-5-ADJCHG: Process 102, Nbr 172.16.20.1
on Serial0/0/0 from LOADING to FULL, Loading Done
LabC#
show ip ospf neighbor
Neighbor ID Pri State Dead Time Address Interface
172.16.20.1 0 FULL/ - 00:00:30 172.16.20.1 Serial0/0/0
LabC#
show ip ospf database
OSPF Router with ID (172.16.40.1) (Process ID 102)
Router Link States (Area 0)
Link ID ADV Router Age Seq# Checksum Link count
172.16.10.1 172.16.10.1 542 0x80000002 0x0067cd 1
172.16.20.1 172.16.20.1 90 0x80000004 0x00a551 3
172.16.40.1 172.16.40.1 37 0x80000004 0x00e47c 4
Net Link States (Area 0)
Link ID ADV Router Age Seq# Checksum
172.16.10.1 172.16.10.1 542 0x80000001 0x00953d
LabC#
show ip ospf interface
Serial0/0/0 is up, line protocol is up
Internet address is 172.16.20.2/24, Area 0
Process ID 102, Router ID 172.16.40.1, Network Type POINT-TO-POINT, Cost: 64
Transmit Delay is 1 sec, State POINT-TO-POINT,
Timer intervals configured, Hello 10, Dead 40, Wait 40, Retransmit 5
Hello due in 00:00:01
Index 1/1, flood queue length 0
Next 0x0(0)/0x0(0)
Last flood scan length is 1, maximum is 1
Last flood scan time is 0 msec, maximum is 0 msec
Neighbor Count is 1 , Adjacent neighbor count is 1
Adjacent with neighbor 172.16.20.1
Suppress hello for 0 neighbor(s)
FastEthernet0/0 is up, line protocol is up
Internet address is 172.16.30.1/24, Area 0
Process ID 102, Router ID 172.16.40.1, Network Type BROADCAST, Cost: 1
Transmit Delay is 1 sec, State DR, Priority 1
Designated Router (ID) 172.16.40.1, Interface address 172.16.30.1
No backup designated router on this network
Timer intervals configured, Hello 10, Dead 40, Wait 40, Retransmit 5
Hello due in 00:00:02
Index 2/2, flood queue length 0
Next 0x0(0)/0x0(0)
Last flood scan length is 1, maximum is 1
Last flood scan time is 0 msec, maximum is 0 msec
Neighbor Count is 0, Adjacent neighbor count is 0
Suppress hello for 0 neighbor(s)
Serial0/0/1 is up, line protocol is up
Internet address is 172.16.40.1/24, Area 0
Process ID 102, Router ID 172.16.40.1, Network Type POINT-TO-POINT, Cost: 64
Transmit Delay is 1 sec, State POINT-TO-POINT,
Timer intervals configured, Hello 10, Dead 40, Wait 40, Retransmit 5
Hello due in 00:00:08
Index 3/3, flood queue length 0
Next 0x0(0)/0x0(0)
Last flood scan length is 1, maximum is 1
Last flood scan time is 0 msec, maximum is 0 msec
Suppress hello for 0 neighbor(s)
we include the three nets conneted to labC in the area.. 20.0, 30.0, and 40.0
link to our left, 20.1 is visible as "Neighbor"
OSPF Database-
Router Link States are
10.1(Router A)
20.1(Router B)
40.1(Router C)(This router)
Net Link States
10.1(Router A)... why does only Router A show here?
Reference- router link state vs net link state
Router Link States are type 1 LSAs. It lists all the routers in the area and the number of interfaces. 40.1 has 4 interfaces
Net Link States are the multi-access networks (Type 2 LSAs). The ADV (advertising router) is the DR.
LabD
LabD(config)#
router ospf 103
LabD(config-router)#
net 172.16.40.2 0.0.0.0 area 0
LabD(config-router)#
net 172.16.50.1 0.0.0.0 area 0
01:37:11: %OSPF-5-ADJCHG: Process 103, Nbr 172.16.40.1
on Serial0/0/0 from LOADING to FULL, Loading Done
LabD#
show ip ospf neighbor
Neighbor ID Pri State Dead Time Address Interface
172.16.40.1 0 FULL/ - 00:00:32 172.16.40.1 Serial0/0/0
LabD#
show ip ospf database
OSPF Router with ID (172.16.50.1) (Process ID 103)
Router Link States (Area 0)
Link ID ADV Router Age Seq# Checksum Link count
172.16.10.1 172.16.10.1 785 0x80000002 0x0067cd 1
172.16.20.1 172.16.20.1 333 0x80000004 0x00a551 3
172.16.40.1 172.16.40.1 111 0x80000005 0x00013b 5
172.16.50.1 172.16.50.1 53 0x80000003 0x001023 3
Net Link States (Area 0)
Link ID ADV Router Age Seq# Checksum
172.16.10.1 172.16.10.1 785 0x80000001 0x00953d
LabD#
show ip ospf interface
Serial0/0/0 is up, line protocol is up
Internet address is 172.16.40.2/24, Area 0
Process ID 103, Router ID 172.16.50.1, Network Type POINT-TO-POINT, Cost: 64
Transmit Delay is 1 sec, State POINT-TO-POINT,
Timer intervals configured, Hello 10, Dead 40, Wait 40, Retransmit 5
Hello due in 00:00:01
Index 1/1, flood queue length 0
Next 0x0(0)/0x0(0)
Last flood scan length is 1, maximum is 1
Last flood scan time is 0 msec, maximum is 0 msec
Neighbor Count is 1 , Adjacent neighbor count is 1
Adjacent with neighbor 172.16.40.1
Suppress hello for 0 neighbor(s)
FastEthernet0/0 is up, line protocol is up
Internet address is 172.16.50.1/24, Area 0
Process ID 103, Router ID 172.16.50.1, Network Type BROADCAST, Cost: 1
Transmit Delay is 1 sec, State WAITING, Priority 1
No designated router on this network
No backup designated router on this network
Timer intervals configured, Hello 10, Dead 40, Wait 40, Retransmit 5
Hello due in 00:00:04
Index 2/2, flood queue length 0
Next 0x0(0)/0x0(0)
Last flood scan length is 1, maximum is 1
Last flood scan time is 0 msec, maximum is 0 msec
Neighbor Count is 0, Adjacent neighbor count is 0
Suppress hello for 0 neighbor(s)
observations
the OSPF databases now match across all 4 routers.
NOTE that this is a database of routers, identified by
router ID. It is not a topology that lists routers AND routes,
like in the "equivalent" eigrp command.show eigrp topology
----------------------------------------------------------------------------------
PAUSE- a tale of a misconfigured network
After a 9 month hiatus, I am reviewing this book and have made it back to Chapter 9. I'm studing this webpage, working thorough the OSPF configurations
described above, and I get stuck on the concept of "link count" under "Router Link States" found in the output of show ip ospf database
The structure of the notes above is helpful, because I was tracking the state of each router BEFORE i made changes to the subsquent router. But just to be sure,
today I decided to recreate the topology, then configure each router one at a time, noting the results as I went.
And I ran into some problems.
Here is the original topology:
And today's recreated toplogy:
After replicating the toplogy and programming the IP addresses on each router, I started on configurations, just like before:
LabA
LabA(config)#
router ospf 100
LabA(config-router)#
net 172.16.10.1 0.0.0.0 area 0
[no output]
LabA#
show ip ospf neighbor
[no output]
LabA#
show ip ospf database
OSPF Router with ID (172.16.10.1) (Process ID 100)
Router Link States (Area 0)
Link ID ADV Router Age Seq# Checksum Link count
172.16.10.1 172.16.10.1 44 0x80000001 0x00b24b 1
LabA#
show ip ospf interface
FastEthernet0/0 is up, line protocol is up
Internet address is 172.16.10.1/24, Area 0
Process ID 100, Router ID 172.16.10.1, Network Type BROADCAST, Cost: 1
Transmit Delay is 1 sec, State DR, Priority 1
Designated Router (ID) 172.16.10.1, Interface address 172.16.10.1
No backup designated router on this network
Timer intervals configured, Hello 10, Dead 40, Wait 40, Retransmit 5
Hello due in 00:00:08
Index 1/1, flood queue length 0
Next 0x0(0)/0x0(0)
Last flood scan length is 1, maximum is 1
Last flood scan time is 0 msec, maximum is 0 msec
Neighbor Count is 0, Adjacent neighbor count is 0
Suppress hello for 0 neighbor(s)
good so far.... On to LabB router
LabB
LabB(config)#
router ospf 101
LabB(config-router)#
net 172.16.10.2 0.0.0.0 area 0
LabB(config-router)#
net 172.16.20.1 0.0.0.0 area 0
01:26:36: %OSPF-5-ADJCHG: Process 101, Nbr 172.16.10.1
on FastEthernet0/0 from LOADING to FULL, Loading Done
LabB#
show ip ospf neighbor
Neighbor ID Pri State Dead Time Address Interface
172.16.10.1 1 FULL/DR 00:00:33 172.16.10.1
LabB#
show ip ospf database
OSPF Router with ID (172.16.20.1) (Process ID 101)
Router Link States (Area 0)
Link ID ADV Router Age Seq# Checksum Link count
172.16.10.1 172.16.10.1 145 0x80000002 0x0067cd 1
172.16.20.1 172.16.20.1 32 0x80000003 0x006e8f 2
Net Link States (Area 0)
Link ID ADV Router Age Seq# Checksum
172.16.10.1 172.16.10.1 145 0x80000001 0x00953d
LabB#
show ip ospf interface
FastEthernet0/0 is up, line protocol is up
Internet address is 172.16.10.2/24, Area 0
Process ID 101, Router ID 172.16.20.1, Network Type BROADCAST, Cost: 1
Transmit Delay is 1 sec, State BDR, Priority 1
Designated Router (ID) 172.16.10.1, Interface address 172.16.10.1
Backup Designated Router (ID) 172.16.20.1, Interface address 172.16.10.2
Timer intervals configured, Hello 10, Dead 40, Wait 40, Retransmit 5
Hello due in 00:00:03
Index 1/1, flood queue length 0
Next 0x0(0)/0x0(0)
Last flood scan length is 1, maximum is 1
Last flood scan time is 0 msec, maximum is 0 msec
Neighbor Count is 1, Adjacent neighbor count is 1
Adjacent with neighbor 172.16.10.1 (Designated Router)
Suppress hello for 0 neighbor(s)
Serial0/0/0 is up, line protocol is up
Internet address is 172.16.20.1/24, Area 0
Process ID 101, Router ID 172.16.20.1, Network Type POINT-TO-POINT, Cost: 64
Transmit Delay is 1 sec, State POINT-TO-POINT,
Timer intervals configured, Hello 10, Dead 40, Wait 40, Retransmit 5
Hello due in 00:00:04
Index 2/2, flood queue length 0
Next 0x0(0)/0x0(0)
Last flood scan length is 1, maximum is 1
Last flood scan time is 0 msec, maximum is 0 msec
Suppress hello for 0 neighbor(s)
still looks good; same as before.... On to LabC router
LabC
LabC(config)#
router ospf 102
LabC(config-router)#
net 172.16.20.2 0.0.0.0 area 0
LabC(config-router)#
net 172.16.30.1 0.0.0.0 area 0
LabC(config-router)#
net 172.16.40.1 0.0.0.0 area 0
01:33:54: %OSPF-5-ADJCHG: Process 102, Nbr 172.16.20.1
on Serial0/0/0 from LOADING to FULL, Loading Done
LabC#
show ip ospf neighbor
[no output]
And here is where I ran into trouble. The show ip ospf neighbor command returns nothing. How can
that be?
After awhile I realized it is due to a misconfiguration in the topology.
For Lab C, I programmed the interfaces as follows:
LabC(config)#
int f0/0
LabC(config-if)#
ip addr 172.16.30.1 255.255.255.0
LabC(config-if)#
no shut
LabC(config-if)#
int s0/0/0
LabC(config-if)#
ip addr 172.16.20.2 255.255.255.0
LabC(config-if)#
no shut
LabC(config-if)#
int s0/0/1
LabC(config-if)#
ip addr 172.16.40.1 255.255.255.0
LabC(config-if)#
no shut
and again here is the topology for that router:
but here is what it SHOULD HAVE looked like (as it did the first time I built it)
S0/0/0 and S0/0/1 are swapped. When I gave the IP 172.16.20.2 to s/0/0/0, thinking that was the interface on the left side
which faces Lab B, I was actually giving 172.16.20.2 to the right side, facing LabC (which has no OSPF configs yet.)
Since the left side got got the IP intended for the right side which was 172.16.40.1
the inverse also occured-
the right side got the IP intended for the left which was 172.16.20.2
LabC left side should have been
s0/0/0 with 20.2
and LabC right side should have been
s0/0/1 with 40.1
The correct IPs were mapped to the correct interfaces. But the mistake happened before I even programmed them.
When I made the connections from LabB to LabC and from LabD to LabC, I plugged then into the wrong ports.
Interestingly.. not only is this causing OSPF to not see B as a neighbor from C.. but B and C cannot ping eachother either.
@B the config is 172.16.20.1/24 @ S0/0/0
@C the config is 172.16.40.1/24 @ S/0/0/1
meaning they are not even on the same network! But the system is not throwing any errors or bringing it to my attention.
It just fails to connect.
To correct the issue, I simply deleted those two links and re-created them. Worth noting, I used the auto select cable here,
which does not ask which interface you want to use when attaching. Earlier I must have plugged the right side first, and
auto select plugged into 0/0/0.
This time I plugged into left side first.
Now LabC OSPF data is reading out correctly...
LabC
LabC(config)#
router ospf 102
LabC(config-router)#
net 172.16.20.2 0.0.0.0 area 0
LabC(config-router)#
net 172.16.30.1 0.0.0.0 area 0
LabC(config-router)#
net 172.16.40.1 0.0.0.0 area 0
01:33:54: %OSPF-5-ADJCHG: Process 102, Nbr 172.16.20.1
on Serial0/0/0 from LOADING to FULL, Loading Done
LabC#
show ip ospf neighbor
Neighbor ID Pri State Dead Time Address Interface
172.16.20.1 0 FULL/ - 00:00:30 172.16.20.1 Serial0/0/0
LabC#
show ip ospf database
OSPF Router with ID (172.16.40.1) (Process ID 102)
Router Link States (Area 0)
Link ID ADV Router Age Seq# Checksum Link count
172.16.10.1 172.16.10.1 542 0x80000002 0x0067cd 1
172.16.20.1 172.16.20.1 90 0x80000004 0x00a551 3
172.16.40.1 172.16.40.1 37 0x80000004 0x00e47c 4
Net Link States (Area 0)
Link ID ADV Router Age Seq# Checksum
172.16.10.1 172.16.10.1 542 0x80000001 0x00953d
LabC#
show ip ospf interface
Serial0/0/0 is up, line protocol is up
Internet address is 172.16.20.2/24, Area 0
Process ID 102, Router ID 172.16.40.1, Network Type POINT-TO-POINT, Cost: 64
Transmit Delay is 1 sec, State POINT-TO-POINT,
Timer intervals configured, Hello 10, Dead 40, Wait 40, Retransmit 5
Hello due in 00:00:01
Index 1/1, flood queue length 0
Next 0x0(0)/0x0(0)
Last flood scan length is 1, maximum is 1
Last flood scan time is 0 msec, maximum is 0 msec
Neighbor Count is 1 , Adjacent neighbor count is 1
Adjacent with neighbor 172.16.20.1
Suppress hello for 0 neighbor(s)
FastEthernet0/0 is up, line protocol is up
Internet address is 172.16.30.1/24, Area 0
Process ID 102, Router ID 172.16.40.1, Network Type BROADCAST, Cost: 1
Transmit Delay is 1 sec, State DR, Priority 1
Designated Router (ID) 172.16.40.1, Interface address 172.16.30.1
No backup designated router on this network
Timer intervals configured, Hello 10, Dead 40, Wait 40, Retransmit 5
Hello due in 00:00:02
Index 2/2, flood queue length 0
Next 0x0(0)/0x0(0)
Last flood scan length is 1, maximum is 1
Last flood scan time is 0 msec, maximum is 0 msec
Neighbor Count is 0, Adjacent neighbor count is 0
Suppress hello for 0 neighbor(s)
Serial0/0/1 is up, line protocol is up
Internet address is 172.16.40.1/24, Area 0
Process ID 102, Router ID 172.16.40.1, Network Type POINT-TO-POINT, Cost: 64
Transmit Delay is 1 sec, State POINT-TO-POINT,
Timer intervals configured, Hello 10, Dead 40, Wait 40, Retransmit 5
Hello due in 00:00:08
Index 3/3, flood queue length 0
Next 0x0(0)/0x0(0)
Last flood scan length is 1, maximum is 1
Last flood scan time is 0 msec, maximum is 0 msec
Suppress hello for 0 neighbor(s)
Which brings me to the original reason I re-created this topology... I was confused about the LINK COUNTS
here:
OSPF Router with ID (172.16.40.1) (Process ID 102)
Router Link States (Area 0)
Link ID ADV Router Age Seq# Checksum Link count
172.16.10.1 172.16.10.1 542 0x80000002 0x0067cd 1
172.16.20.1 172.16.20.1 90 0x80000004 0x00a551 3
172.16.40.1 172.16.40.1 37 0x80000004 0x00e47c 4
Net Link States (Area 0)
Link ID ADV Router Age Seq# Checksum
172.16.10.1 172.16.10.1 542 0x80000001 0x00953d
The steps of recreating the lab were helpful, but this link answered the question:
Here is the output of each router's command show ip ospf interface as they are
set up one at a time.
LabA - No OSPF at B, C, or D yet
show ip ospf database
OSPF Router with ID (172.16.10.1) (Process ID 100)
Router Link States (Area 0)
Link ID ADV Router Age Seq# Checksum Link count
172.16.10.1 172.16.10.1 44 0x80000001 0x00b24b 1
LabB - No OSPF at C or D yet
show ip ospf database
OSPF Router with ID (172.16.20.1) (Process ID 101)
Router Link States (Area 0)
Link ID ADV Router Age Seq# Checksum Link count
172.16.10.1 172.16.10.1 145 0x80000002 0x0067cd 1
172.16.20.1 172.16.20.1 32 0x80000003 0x006e8f 2
Net Link States (Area 0)
Link ID ADV Router Age Seq# Checksum
172.16.10.1 172.16.10.1 145 0x80000001 0x00953d
the 20.2 interface on this router has 2 ospf links.
The left-facing out to RA, a crossover cable
The right-facing out to RC, a serial cable.
If the solution I found is correct, why is this serial link not being counted twice? The solution (I think)
is revealed after the configuration of the next router...
LabC - No OSPF at D yet
show ip ospf database
OSPF Router with ID (172.16.40.1) (Process ID 102)
Router Link States (Area 0)
Link ID ADV Router Age Seq# Checksum Link count
172.16.10.1 172.16.10.1 542 0x80000002 0x0067cd 1
172.16.20.1 172.16.20.1 90 0x80000004 0x00a551 3
172.16.40.1 172.16.40.1 37 0x80000004 0x00e47c 4
Net Link States (Area 0)
Link ID ADV Router Age Seq# Checksum
172.16.10.1 172.16.10.1 542 0x80000001 0x00953d
NOW we can see that the 20.1 link, which is the right-facing interface on LabB.. aka the router ID..
has THREE OSPF links.
Nothing changed on the left side of B. But on the right side, we now have an active OSPF router at the
other end of the link. This leads me to believe that the forum post was correct that 'serial links are counted twice',
but, more specifically, BOTH ENDS of the serial(PPP) link are counted... IF there is an OSPF router on each end.
This is backed up by the fact that LabC, OSPF id 40.1, has four OSPF links. The top-facing link to the 30
network DOES count.. even though it has no OSPF router on the other end. It counts because it's not a serial link.
The requirement of having an OSPF router on the other end for an interface to count here, only applies
to serial links. And pertains to BOTH ends of the link being counted.
In LabC's case, we have one serial at left, being counted twice. One ethernet at top, being counted once. And
one serial at right only being counted once because LabD is not active with OSPF yet.
If this is correct, then we should see Lab C's 40.1 count go to 5 after LabD is set for OSPF....
LabD - all 4 routers have OSPF
show ip ospf database
OSPF Router with ID (172.16.50.1) (Process ID 103)
Router Link States (Area 0)
Link ID ADV Router Age Seq# Checksum Link count
172.16.10.1 172.16.10.1 785 0x80000002 0x0067cd 1
172.16.20.1 172.16.20.1 333 0x80000004 0x00a551 3
172.16.40.1 172.16.40.1 111 0x80000005 0x00013b 5
172.16.50.1 172.16.50.1 53 0x80000003 0x001023 3
Net Link States (Area 0)
Link ID ADV Router Age Seq# Checksum
172.16.10.1 172.16.10.1 785 0x80000001 0x00953d
and back to LabC.....
show ip ospf database
OSPF Router with ID (172.16.40.1) (Process ID 102)
Router Link States (Area 0)
Link ID ADV Router Age Seq# Checksum Link count
172.16.10.1 172.16.10.1 1174 0x80000002 0x0067cd 1
172.16.20.1 172.16.20.1 722 0x80000004 0x00a551 3
172.16.40.1 172.16.40.1 500 0x80000005 0x00013b 5
172.16.50.1 172.16.50.1 441 0x80000003 0x001023 3
Net Link States (Area 0)
Link ID ADV Router Age Seq# Checksum
172.16.10.1 172.16.10.1 1174 0x80000001 0x00953d
Looks good! The link count for each router makes sense if you count the serial interfaces twice (one for each end).
the OSPF databases now match across all 4 routers.
NOTE that this is a database of routers, identified by
router ID. It is not a topology that lists routers AND routes, like in
the "equivalent" eigrp command show eigrp topology
Note that the .30 network is NOT represented here.
LabA#
show ip ospf database
OSPF Router with ID (172.16.10.1) (Process ID 100)
Router Link States (Area 0)
Link ID ADV Router Age Seq# Checksum Link count
172.16.10.1 172.16.10.1 1138 0x80000002 0x0067cd 1
172.16.20.1 172.16.20.1 686 0x80000004 0x00a551 3
172.16.40.1 172.16.40.1 463 0x80000005 0x00013b 5
172.16.50.1 172.16.50.1 404 0x80000003 0x001023 3
Net Link States (Area 0)
Link ID ADV Router Age Seq# Checksum
172.16.10.1 172.16.10.1 1138 0x80000001 0x00953d
LabB#
show ip ospf database
OSPF Router with ID (172.16.20.1) (Process ID 101)
Router Link States (Area 0)
Link ID ADV Router Age Seq# Checksum Link count
172.16.10.1 172.16.10.1 1151 0x80000002 0x0067cd 1
172.16.20.1 172.16.20.1 699 0x80000004 0x00a551 3
172.16.40.1 172.16.40.1 476 0x80000005 0x00013b 5
172.16.50.1 172.16.50.1 417 0x80000003 0x001023 3
Net Link States (Area 0)
Link ID ADV Router Age Seq# Checksum
172.16.10.1 172.16.10.1 1151 0x80000001 0x00953d
LabC#
show ip ospf database
OSPF Router with ID (172.16.40.1) (Process ID 102)
Router Link States (Area 0)
Link ID ADV Router Age Seq# Checksum Link count
172.16.10.1 172.16.10.1 1174 0x80000002 0x0067cd 1
172.16.20.1 172.16.20.1 722 0x80000004 0x00a551 3
172.16.40.1 172.16.40.1 500 0x80000005 0x00013b 5
172.16.50.1 172.16.50.1 441 0x80000003 0x001023 3
Net Link States (Area 0)
Link ID ADV Router Age Seq# Checksum
172.16.10.1 172.16.10.1 1174 0x80000001 0x00953d
LabD#
show ip ospf database
OSPF Router with ID (172.16.50.1) (Process ID 103)
Router Link States (Area 0)
Link ID ADV Router Age Seq# Checksum Link count
172.16.10.1 172.16.10.1 785 0x80000002 0x0067cd 1
172.16.20.1 172.16.20.1 333 0x80000004 0x00a551 3
172.16.40.1 172.16.40.1 111 0x80000005 0x00013b 5
172.16.50.1 172.16.50.1 53 0x80000003 0x001023 3
Net Link States (Area 0)
Link ID ADV Router Age Seq# Checksum
172.16.10.1 172.16.10.1 785 0x80000001 0x00953d
Below is our routing tables with OSPF data. We do see the .30 network here.
Everyone can reach it:
LabA via LabB's 10.2
LabB via LabC's 20.2
LabC via direct connection
LabD via LabC's 40.1
LabA#
show ip route
172.16.0.0/16 is variably subnetted, 6 subnets, 2 masks
C 172.16.10.0/24 is directly connected, FastEthernet0/0
L 172.16.10.1/32 is directly connected, FastEthernet0/0
O 172.16.20.0/24 [110/65] via 172.16.10.2, 00:28:03, FastEthernet0/0
O 172.16.30.0/24 [110/66] via 172.16.10.2, 00:21:35, FastEthernet0/0
O 172.16.40.0/24 [110/129] via 172.16.10.2, 00:21:25, FastEthernet0/0
O 172.16.50.0/24 [110/130] via 172.16.10.2, 00:17:40, FastEthernet0/0
LabB#
show ip route
172.16.0.0/16 is variably subnetted, 7 subnets, 2 masks
C 172.16.10.0/24 is directly connected, FastEthernet0/0
L 172.16.10.2/32 is directly connected, FastEthernet0/0
C 172.16.20.0/24 is directly connected, Serial0/0/0
L 172.16.20.1/32 is directly connected, Serial0/0/0
O 172.16.30.0/24 [110/65] via 172.16.20.2, 00:27:04, Serial0/0/0
O 172.16.40.0/24 [110/128] via 172.16.20.2, 00:26:54, Serial0/0/0
O 172.16.50.0/24 [110/129] via 172.16.20.2, 00:23:09, Serial0/0/0
LabC#
show ip route
172.16.0.0/16 is variably subnetted, 8 subnets, 2 masks
O 172.16.10.0/24 [110/65] via 172.16.20.1, 00:27:52, Serial0/0/0
C 172.16.20.0/24 is directly connected, Serial0/0/0
L 172.16.20.2/32 is directly connected, Serial0/0/0
C 172.16.30.0/24 is directly connected, FastEthernet0/0
L 172.16.30.1/32 is directly connected, FastEthernet0/0
C 172.16.40.0/24 is directly connected, Serial0/0/1
L 172.16.40.1/32 is directly connected, Serial0/0/1
O 172.16.50.0/24 [110/65] via 172.16.40.2, 00:23:36, Serial0/0/1
LabD#
show ip route
172.16.0.0/16 is variably subnetted, 7 subnets, 2 masks
O 172.16.10.0/24 [110/129] via 172.16.40.1, 00:25:20, Serial0/0/0
O 172.16.20.0/24 [110/128] via 172.16.40.1, 00:25:20, Serial0/0/0
O 172.16.30.0/24 [110/65] via 172.16.40.1, 00:25:20, Serial0/0/0
C 172.16.40.0/24 is directly connected, Serial0/0/0
L 172.16.40.2/32 is directly connected, Serial0/0/0
C 172.16.50.0/24 is directly connected, FastEthernet0/0
L 172.16.50.1/32 is directly connected, FastEthernet0/0
moving on.......
9.5 - OSPF DR and BDR Elections
EachRouter(config)#
hostname X (A, B, or C)
EachRouter(config)#
line con 0
EachRouter(config-line)#
exec-timeout 0 0
A(config)#
int f0/0
A(config-if)#
ip addr 10.1.1.1 255.255.255.0
A(config-if)#
no shut
A(config)#
router ospf 12345
A(config-router)#
net 10.1.1.0 0.0.0.255 area 0
00:23:30: %OSPF-5-ADJCHG: Process 12345, Nbr 10.1.1.3 on FastEthernet0/0 from LOADING to FULL, Loading Done
00:23:30: %OSPF-5-ADJCHG: Process 12345, Nbr 10.1.1.2 on FastEthernet0/0 from LOADING to FULL, Loading Done
A#
show ip ospf int
note this output was generated AFTER all 3 routers set for OSPF
FastEthernet0/0 is up, line protocol is up
Internet address is 10.1.1.1/24, Area 0
Process ID 12345, Router ID 10.1.1.1, Network Type BROADCAST, Cost: 1
Transmit Delay is 1 sec, State DROTHER, Priority 1
Designated Router (ID) 10.1.1.3, Interface address 10.1.1.3
Backup Designated Router (ID) 10.1.1.2, Interface address 10.1.1.2
Timer intervals configured, Hello 10, Dead 40, Wait 40, Retransmit 5
Hello due in 00:00:04
Index 1/1, flood queue length 0
Next 0x0(0)/0x0(0)
Last flood scan length is 1, maximum is 1
Last flood scan time is 0 msec, maximum is 0 msec
Neighbor Count is 2, Adjacent neighbor count is 2
Adjacent with neighbor 10.1.1.3 (Designated Router)
Adjacent with neighbor 10.1.1.2 (Backup Designated Router)
Suppress hello for 0 neighbor(s)
A(config-if)#shut
A(config-if)#
%LINK-5-CHANGED: Interface FastEthernet0/0, changed state to administratively down
%LINEPROTO-5-UPDOWN: Line protocol on Interface FastEthernet0/0, changed state to down
00:40:28: %OSPF-5-ADJCHG: Process 12345, Nbr 10.1.1.2 on FastEthernet0/0 from FULL to DOWN, Neighbor Down: Interface down or detached
00:40:28: OSPF: Build router LSA for area 0, router ID 10.1.1.1, seq 0xffffffff80000003
00:40:28: %OSPF-5-ADJCHG: Process 12345, Nbr 10.1.1.3 on FastEthernet0/0 from FULL to DOWN, Neighbor Down: Interface down or detached
00:40:28: OSPF: Build router LSA for area 0, router ID 10.1.1.1, seq 0xffffffff80000004
00:40:28: OSPF: Build router LSA for area 0, router ID 10.1.1.1, seq 0xffffffff80000004
A(config-if)#no shut
A(config-if)#
%LINK-5-CHANGED: Interface FastEthernet0/0, changed state to up
%LINEPROTO-5-UPDOWN: Line protocol on Interface FastEthernet0/0, changed state to up
00:40:48: OSPF: Build router LSA for area 0, router ID 10.1.1.1, seq 0xffffffff80000004
00:41:27: OSPF: Backup seen Event before WAIT timer on FastEthernet0/0
00:41:27: OSPF: DR/BDR election on FastEthernet0/0
00:41:27: OSPF: Elect BDR 10.1.1.2
00:41:27: OSPF: Elect DR 10.1.1.3
00:41:27: DR: 10.1.1.3 (Id) BDR: 10.1.1.2 (Id)
00:41:27: OSPF: Send DBD to 10.1.1.3 on FastEthernet0/0 seq 0x5accb8e2 opt 0x00 flag 0x7 len 32
B(config)#
int f0/0
B(config-if)#
ip addr 10.1.1.2 255.255.255.0
B(config-if)#
no shut
B(config)#
router ospf 12345
B(config-router)#
net 10.1.1.0 0.0.0.255 area 0
00:23:29: %OSPF-5-ADJCHG: Process 12345, Nbr 10.1.1.3 on FastEthernet0/0 from LOADING to FULL, Loading Done
00:23:29: %OSPF-5-ADJCHG: Process 12345, Nbr 10.1.1.1 on FastEthernet0/0 from LOADING to FULL, Loading Done
B#
show ip ospf int
note this output was generated AFTER all 3 routers set for OSPF
FastEthernet0/0 is up, line protocol is up
Internet address is 10.1.1.2/24, Area 0
Process ID 12345, Router ID 10.1.1.2, Network Type BROADCAST, Cost: 1
Transmit Delay is 1 sec, State BDR, Priority 1
Designated Router (ID) 10.1.1.3, Interface address 10.1.1.3
Backup Designated Router (ID) 10.1.1.2, Interface address 10.1.1.2
Timer intervals configured, Hello 10, Dead 40, Wait 40, Retransmit 5
Hello due in 00:00:05
Index 1/1, flood queue length 0
Next 0x0(0)/0x0(0)
Last flood scan length is 1, maximum is 1
Last flood scan time is 0 msec, maximum is 0 msec
Neighbor Count is 2, Adjacent neighbor count is 2
Adjacent with neighbor 10.1.1.1
Adjacent with neighbor 10.1.1.3 (Designated Router)
Suppress hello for 0 neighbor(s)
B#debug ip ospf adj
OSPF adjacency events debugging is on
B#
00:39:21: OSPF: DR/BDR election on FastEthernet0/0
00:39:21: OSPF: Elect BDR 10.1.1.2
00:39:21: OSPF: Elect DR 10.1.1.3
00:39:21: DR: 10.1.1.3 (Id) BDR: 10.1.1.2 (Id)
00:41:01: %OSPF-5-ADJCHG: Process 12345, Nbr 10.1.1.1 on FastEthernet0/0 from FULL to DOWN, Neighbor Down: Dead timer expired
00:41:01: %OSPF-5-ADJCHG: Process 12345, Nbr 10.1.1.1 on FastEthernet0/0 from FULL to DOWN, Neighbor Down: Interface down or detached
00:41:01: OSPF: Build router LSA for area 0, router ID 10.1.1.2, seq 0xffffffff80000003
00:41:01: OSPF: DR/BDR election on FastEthernet0/0
00:41:01: OSPF: Elect BDR 10.1.1.2
00:41:01: OSPF: Elect DR 10.1.1.3
C(config)#
int f0/0
C(config-if)#
ip addr 10.1.1.3 255.255.255.0
C(config-if)#
no shut
C(config)#
router ospf 12345
C(config-router)#
net 10.1.1.0 0.0.0.255 area 0
00:23:27: %OSPF-5-ADJCHG: Process 12345, Nbr 10.1.1.1 on FastEthernet0/0 from LOADING to FULL, Loading Done
00:23:27: %OSPF-5-ADJCHG: Process 12345, Nbr 10.1.1.2 on FastEthernet0/0 from LOADING to FULL, Loading Done
C#
show ip ospf int
note this output was generated AFTER all 3 routers set for OSPF
FastEthernet0/0 is up, line protocol is up
Internet address is 10.1.1.3/24, Area 0
Process ID 12345, Router ID 10.1.1.3, Network Type BROADCAST, Cost: 1
Transmit Delay is 1 sec, State DR, Priority 1
Designated Router (ID) 10.1.1.3, Interface address 10.1.1.3
Backup Designated Router (ID) 10.1.1.2, Interface address 10.1.1.2
Timer intervals configured, Hello 10, Dead 40, Wait 40, Retransmit 5
Hello due in 00:00:00
Index 1/1, flood queue length 0
Next 0x0(0)/0x0(0)
Last flood scan length is 1, maximum is 1
Last flood scan time is 0 msec, maximum is 0 msec
Neighbor Count is 2, Adjacent neighbor count is 2
Adjacent with neighbor 10.1.1.1
Adjacent with neighbor 10.1.1.2 (Backup Designated Router)
Suppress hello for 0 neighbor(s)
C#debug ip ospf adj
OSPF adjacency events debugging is on
C#
00:39:19: OSPF: DR/BDR election on FastEthernet0/0
00:39:19: OSPF: Elect BDR 10.1.1.2
00:39:19: OSPF: Elect DR 10.1.1.3
00:39:19: DR: 10.1.1.3 (Id) BDR: 10.1.1.2 (Id)
00:40:59: %OSPF-5-ADJCHG: Process 12345, Nbr 10.1.1.1 on FastEthernet0/0 from FULL to DOWN, Neighbor Down: Dead timer expired
00:40:59: %OSPF-5-ADJCHG: Process 12345, Nbr 10.1.1.1 on FastEthernet0/0 from FULL to DOWN, Neighbor Down: Interface down or detached
00:40:59: OSPF: Build router LSA for area 0, router ID 10.1.1.3, seq 0xffffffff80000003
00:40:59: OSPF: Build net LSA for area 0, router ID 10.1.1.3, seq 0xffffffff80000003
00:40:59: OSPF: DR/BDR election on FastEthernet0/0
00:40:59: OSPF: Elect BDR 10.1.1.2
00:40:59: OSPF: Elect DR 10.1.1.3
DR and BDR automtically set based on higest IP address
Note our network type is BROADCAST because we're using ethernet interfaces...
it would be point-to-point if using a serial connection
we want to manually overide the priority of the router. ZERO priority means it wont participate in the election process
MAX priority of 255 means no other router can beat it for DR
We'll set the priority for router A to 3.
It will beome the DR only after we shut/no shut the interface router
AND
manually power on/off the other two routers
A(config)#
int f0/0
A(config-int)#
ip ospf priority 3
A(config-int)#
shut
A(config-int)#
no shut
A#
debug ip ospf adj
B#
debug ip ospf adj
00:05:50: OSPF: DR/BDR election on FastEthernet0/0
00:05:50: OSPF: Elect BDR 10.1.1.2
00:05:50: OSPF: Elect DR 10.1.1.1
00:05:50: OSPF: Elect BDR 10.1.1.2
00:05:50: OSPF: Elect DR 10.1.1.1
00:05:50: DR: 10.1.1.1 (Id) BDR: 10.1.1.2 (Id)
00:05:50: OSPF: Send DBD to 10.1.1.1 on FastEthernet0/0 seq 0x10164ebb opt 0x00 flag 0x7 len 32
00:05:50: OSPF: Build router LSA for area 0, router ID 10.1.1.2, seq 0xffffffff80000002
00:05:52: OSPF: Rcv DBD from 10.1.1.1 on FastEthernet0/0 seq 0x20368093 opt 0x00 flag 0x7 len 32 mtu 1500 state EXSTART
00:05:52: OSPF: First DBD and we are not SLAVE
00:05:55: OSPF: Send DBD to 10.1.1.1 on FastEthernet0/0 seq 0x10164ebb opt 0x00 flag 0x7 len 32
00:05:55: OSPF: Rcv DBD from 10.1.1.1 on FastEthernet0/0 seq 0x10164ebb opt 0x00 flag 0x2 len 112 mtu 1500 state EXSTART
00:05:55: OSPF: NBR Negotiation Done. We are the MASTER
00:05:55: OSPF: Send DBD to 10.1.1.1 on FastEthernet0/0 seq 0x10164ebc opt 0x00 flag 0x3 len 52
00:05:55: OSPF: Rcv DBD from 10.1.1.1 on FastEthernet0/0 seq 0x10164ebc opt 0x00 flag 0x0 len 32 mtu 1500 state EXCHANGE
00:05:55: OSPF: Send DBD to 10.1.1.1 on FastEthernet0/0 seq 0x10164ebd opt 0x00 flag 0x1 len 32
00:05:55: OSPF: Rcv DBD from 10.1.1.1 on FastEthernet0/0 seq 0x10164ebd opt 0x00 flag 0x0 len 32 mtu 1500 state EXCHANGE
00:05:55: Exchange Done with 10.1.1.1 on FastEthernet0/0
00:05:55: OSPF: Database request to 10.1.1.1
00:05:55: OSPF: sent LS REQ packet to 10.1.1.1, length 36
00:05:55: OSPF: Rcv DBD from 10.1.1.1 on FastEthernet0/0 seq 0x10164ebd opt 0x00 flag 0x0 len 32 mtu 1500 state LOADING
00:05:55: Synchronized with with 10.1.1.1 on FastEthernet0/0, state FULL
00:05:55: %OSPF-5-ADJCHG: Process 12345, Nbr 10.1.1.1 on FastEthernet0/0 from LOADING to FULL, Loading Done
00:05:55: OSPF: Build router LSA for area 0, router ID 10.1.1.2, seq 0xffffffff80000002
C#
debug ip ospf adj
00:06:13: OSPF: DR/BDR election on FastEthernet0/0
00:06:13: OSPF: Elect BDR 10.1.1.2
00:06:13: OSPF: Elect DR 10.1.1.1
00:06:13: DR: 10.1.1.1 (Id) BDR: 10.1.1.2 (Id)
00:06:13: OSPF: Send DBD to 10.1.1.1 on FastEthernet0/0 seq 0x1cc5536d opt 0x00 flag 0x7 len 32
00:06:13: OSPF: Send DBD to 10.1.1.2 on FastEthernet0/0 seq 0x3d51ca66 opt 0x00 flag 0x7 len 32
00:06:13: OSPF: Build router LSA for area 0, router ID 10.1.1.3, seq 0xffffffff80000002
00:06:17: OSPF: Rcv DBD from 10.1.1.1 on FastEthernet0/0 seq 0x6b532eec opt 0x00 flag 0x7 len 32 mtu 1500 state EXSTART
00:06:17: OSPF: First DBD and we are not SLAVE
00:06:17: OSPF: Rcv DBD from 10.1.1.2 on FastEthernet0/0 seq 0x783110f4 opt 0x00 flag 0x7 len 32 mtu 1500 state EXSTART
00:06:17: OSPF: First DBD and we are not SLAVE
00:06:18: OSPF: Send DBD to 10.1.1.2 on FastEthernet0/0 seq 0x3d51ca66 opt 0x00 flag 0x7 len 32
00:06:18: OSPF: Send DBD to 10.1.1.1 on FastEthernet0/0 seq 0x1cc5536d opt 0x00 flag 0x7 len 32
00:06:18: OSPF: Rcv DBD from 10.1.1.2 on FastEthernet0/0 seq 0x3d51ca66 opt 0x00 flag 0x2 len 132 mtu 1500 state EXSTART
00:06:18: OSPF: NBR Negotiation Done. We are the MASTER
00:06:18: OSPF: Send DBD to 10.1.1.2 on FastEthernet0/0 seq 0x3d51ca67 opt 0x00 flag 0x3 len 52
00:06:18: OSPF: Rcv DBD from 10.1.1.1 on FastEthernet0/0 seq 0x1cc5536d opt 0x00 flag 0x2 len 132 mtu 1500 state EXSTART
00:06:18: OSPF: NBR Negotiation Done. We are the MASTER
00:06:18: OSPF: Send DBD to 10.1.1.1 on FastEthernet0/0 seq 0x1cc5536e opt 0x00 flag 0x3 len 52
00:06:18: OSPF: Rcv DBD from 10.1.1.2 on FastEthernet0/0 seq 0x3d51ca67 opt 0x00 flag 0x0 len 32 mtu 1500 state EXCHANGE
00:06:18: OSPF: Send DBD to 10.1.1.2 on FastEthernet0/0 seq 0x3d51ca68 opt 0x00 flag 0x1 len 32
00:06:18: OSPF: Rcv DBD from 10.1.1.1 on FastEthernet0/0 seq 0x1cc5536e opt 0x00 flag 0x0 len 32 mtu 1500 state EXCHANGE
00:06:18: OSPF: Send DBD to 10.1.1.1 on FastEthernet0/0 seq 0x1cc5536f opt 0x00 flag 0x1 len 32
00:06:18: OSPF: Rcv DBD from 10.1.1.2 on FastEthernet0/0 seq 0x3d51ca68 opt 0x00 flag 0x0 len 32 mtu 1500 state EXCHANGE
00:06:18: Exchange Done with 10.1.1.2 on FastEthernet0/0
00:06:18: OSPF: Database request to 10.1.1.2
00:06:18: OSPF: sent LS REQ packet to 10.1.1.2, length 48
00:06:18: OSPF: Rcv DBD from 10.1.1.1 on FastEthernet0/0 seq 0x1cc5536f opt 0x00 flag 0x0 len 32 mtu 1500 state EXCHANGE
verify on all three routers
A#
show ip ospf interface f0/0
FastEthernet0/0 is up, line protocol is up
Internet address is 10.1.1.1/24, Area 0
Process ID 12345, Router ID 10.1.1.1, Network Type BROADCAST, Cost: 1
Transmit Delay is 1 sec, State DR, Priority 3
Designated Router (ID) 10.1.1.1, Interface address 10.1.1.1
Backup Designated Router (ID) 10.1.1.2, Interface address 10.1.1.2
Timer intervals configured, Hello 10, Dead 40, Wait 40, Retransmit 5
Hello due in 00:00:09
Index 1/1, flood queue length 0
Next 0x0(0)/0x0(0)
Last flood scan length is 1, maximum is 1
Last flood scan time is 0 msec, maximum is 0 msec
Neighbor Count is 2, Adjacent neighbor count is 2
Adjacent with neighbor 10.1.1.2 (Backup Designated Router)
Adjacent with neighbor 10.1.1.3
Suppress hello for 0 neighbor(s)
A#
show ip ospf neighbor
Neighbor ID Pri State Dead Time Address Interface
10.1.1.2 1 FULL/BDR 00:00:37 10.1.1.2 FastEthernet0/0
10.1.1.3 1 FULL/DROTHER 00:00:30 10.1.1.3 FastEthernet0/0
B#
show ip ospf interface f0/0
FastEthernet0/0 is up, line protocol is up
Internet address is 10.1.1.2/24, Area 0
Process ID 12345, Router ID 10.1.1.2, Network Type BROADCAST, Cost: 1
Transmit Delay is 1 sec, State BDR, Priority 1
Designated Router (ID) 10.1.1.1, Interface address 10.1.1.1
Backup Designated Router (ID) 10.1.1.2, Interface address 10.1.1.2
Timer intervals configured, Hello 10, Dead 40, Wait 40, Retransmit 5
Hello due in 00:00:08
Index 1/1, flood queue length 0
Next 0x0(0)/0x0(0)
Last flood scan length is 1, maximum is 1
Last flood scan time is 0 msec, maximum is 0 msec
Neighbor Count is 2, Adjacent neighbor count is 2
Adjacent with neighbor 10.1.1.1 (Designated Router)
Adjacent with neighbor 10.1.1.3
Suppress hello for 0 neighbor(s)
B#
show ip ospf neighbor
Neighbor ID Pri State Dead Time Address Interface
10.1.1.1 3 FULL/DR 00:00:35 10.1.1.1 FastEthernet0/0
10.1.1.3 1 FULL/DROTHER 00:00:31 10.1.1.3 FastEthernet0/0
C#
show ip ospf interface f0/0
FastEthernet0/0 is up, line protocol is up
Internet address is 10.1.1.3/24, Area 0
Process ID 12345, Router ID 10.1.1.3, Network Type BROADCAST, Cost: 1
Transmit Delay is 1 sec, State DROTHER, Priority 1
Designated Router (ID) 10.1.1.1, Interface address 10.1.1.1
Backup Designated Router (ID) 10.1.1.2, Interface address 10.1.1.2
Timer intervals configured, Hello 10, Dead 40, Wait 40, Retransmit 5
Hello due in 00:00:06
Index 1/1, flood queue length 0
Next 0x0(0)/0x0(0)
Last flood scan length is 1, maximum is 1
Last flood scan time is 0 msec, maximum is 0 msec
Neighbor Count is 2, Adjacent neighbor count is 2
Adjacent with neighbor 10.1.1.1 (Designated Router)
Adjacent with neighbor 10.1.1.2 (Backup Designated Router)
Suppress hello for 0 neighbor(s)
C#
show ip ospf neighbor/span>
Neighbor ID Pri State Dead Time Address Interface
10.1.1.1 3 FULL/DR 00:00:35 10.1.1.1 FastEthernet0/0
10.1.1.2 1 FULL/BDR 00:00:37 10.1.1.2 FastEthernet0/0
Router1 is the DR with priority 3
still need more work to understand the output of the defbu ospf adj
Chapter 9 Review Questions
1. There are three possible routes for a router to reach a destination network:
OSPF with a metric of 782
RIPv2 with a metric of 4
EIGRP with a composite metric of 20514560
Which route will be installed in the routing table?
EIGRP because it has the lowest Administrative Distance, and AD is always used before metric
ADs are:
ExternalEIGRP 170
RIP 120
OSPF 110
IGRP 100
EIGRP 90
Static 1
Connected 0
2. Which EIGRP information is held in RAM and maintained through the use of Hello and update packets?
Neighbor table
and
toplogy table
3. Describe the process identifier that is used to run OSPF on a router
The OSPF process id is only locally significant. A random number can be selected. But it's required in order to identify
a unique OSPF database instance. You can use the same, or a different number on each router, doesnt matter.
Any number can be used from 1 to 65,535. Process ID is supplied as an argument to the command router ospf
NOT to be confused with the area number which can be any number up to 4 billion. The area id identifies a logical grouping of routers.
area id is supplied as argument to the OSPF network id and mask command
Ex:
R1(config)#
router ospf 12345
R1(config-router)#
net 10.1.1.0 0.0.0.255 area 0
4. Where are EIGRP successor routes stored?
EIGRP succesor routers are stored in the routing table. The "succesor" is the successful or primary route.
The successor route is ALSO listed in the topology table,
The feasible successor is a BACKUP route and will ONLY be listed in the topology table, unless the successor route fails,
in which case the feasible successor would become the successor
Note that my EIGRP setup doesnt seem to folow this.
CTRL-F jump to "remotely connected via remote ingress ip address"
the book states that EIGRP is automatically load-balancing our two links from R1 to corp.. is this why there is no feasible successor here?
I did some research and found that in our case, we are not using a Feasible Successor. You CAN have two Successors with equal metric, in which case EIGRP will
automatically load-balance.
But I wanted to find out what a Feasible Successor actually looks like in the EIGRP topology table..
Kevin Wallace EIGRP article
Conclusion:
EIGRP topology table wouldnt specifically say "Feasible Successor", but you would know by two routes appearing, one with a lower metric.
In my topology we have two equal-metric links and they are both considered "Successors". EIGRP uses them equally (load-balanced)
Corp#
show ip eigrp toplogy
[cut]
P 172.16.10.0/24, 1 successors, FD is 28160
via 10.1.5.2 (28160/25600), FastEthernet0/0
P 192.168.10.0/24, 2 successors, FD is 2172416
via 10.1.3.2 (2172416/28160), Serial0/0/1
via 10.1.2.2 (2172416/28160), Serial0/0/0
P 192.168.20.0/24, 2 successors, FD is 2172416
via 10.1.3.2 (2172416/28160), Serial0/0/1
via 10.1.2.2 (2172416/28160), Serial0/0/0
P 192.168.30.0/24, 1 successors, FD is 2172416
via 10.1.4.2 (2172416/28160), Serial0/1/0
P 192.168.40.0/24, 1 successors, FD is 2172416
via 10.1.4.2 (2172416/28160), Serial0/1/0
5. Which command will display all the EIGRP feasible successor routes to a known router.
show ip eigrp topology
6. Find the configuration error. You type the following into your router, but dont see any routes in the routing table?
Router(config)#
router ospf 1
Router(config-router)#
network 10.0.0.0 255.0.0.0
wrong wildcard mask
instead, could have used
0.255.255.255
or
0.0.0.255
the point is we need to specify the first octet as "allowed" into our OSPF config with a 0 mask.
The remaining bits are 'dont care' bits aka 'wildcard' aka 255
7. Which three protocols support VLSM, summarization, and discontigous networking?
RIPv2
EIGRP
OSPF
all 3 build and mainting routing tables, provide classless routing which allows VLSM, summarization, and discontigous networks
RIPv1 and IGRP build/maintain routing tables, but dont offer classless routing
8. Which are true regarding OSPF areas?
the 'backbone' is area 0
if using other areas, they all must directly connect to area 0
9. Which two network types have a designated router and a backup designated router?
Broadcast
NBMA- Non broadcast multi access. Ex: Frame Relay
network types that DO NOT use DR/BDR:
point to point
broadcast multipoint
10. You need to configure a router with a distance-vector protocol that allows classless routing. Which to use?
EIGRP is considered 'advanced distance vector' (ripv2 wasnt an option)
11. You need the IP address of the devices with which the router has established an adjacency.
Also, the retransmit interval and the queue counts for the adjacent routers need to be checked. What command will display the required information?
show ip eigrp neighbors
WRONG: show ip eigrp adjacency - there is no such command.. the word 'adjacency' is only used with debug ip OSPF adjacency
here are the possible commands for show ip eigrp and debug ip eigrp
show ip eigrp ?
interfaces IP-EIGRP interfaces
neighbors IP-EIGRP neighbors
topology IP-EIGRP Topology Table
traffic IP-EIGRP Traffic Statistics
debug ip eigrp ?
summary IP-EIGRP summary route processing
12. You cant establish an adjacency relationship on a common ethernet link between two routers. Based on the output below, what is the cause of the problem?
RouterA#
Ethernet0/0 is up, line protocol is up
Internet Address 172.16.1.2/16, Area 0
Process ID 2, Router ID 172.126.1.2, Network Type BROADCAST, Cost: 10
Transmit Delay is 1 sec, State DR, Priority 1
Designated Router (ID) 172.16.1.2, interface address 172.16.1.1.
No backup designated router on this network
Timer intervals configured, Hello 5, Dead 20, Wait 20, Retransmit 5
Router B#
Internet Address 172.16.1.1/16, Area 0
Process ID 2, Router ID 172.126.1.1, Network Type BROADCAST, Cost: 10
Transmit Delay is 1 sec, State DR, Priority 1
Designated Router (ID) 172.16.1.1, interface address 172.16.1.2.
No backup designated router on this network
Timer intervals configured, Hello 10, Dead 40, Wait 40, Retransmit 5
mismatched timer intervals
OSPF default Hello is 10 and Dead is 40... RouterA was modified
13. Which is true regarding EIGRP successor routes?
Used in the routing table
also appears in the topolgy table
may (or may not) have a backup feasabile successor
14. Which type of OSPF network will elect a backup designated router?
broadcast multi-access
non-broadcast multiaccess
types of network that will NOT elect a BDR:
point to point and brodacast multipoint (hub/spoke topology)
15. Which two commands will place network 10.2.3.0/24 into area 0?
Router(config)#
router ospf 10
Router(config-router)#
network 10.2.3.0 0.0.0.255 area 0
16. With which network type will OSPF establish router adjacencies but not perform the DR/BDR election process?
Point to point
no election process occurs, there is never a DR on point to point
17. What are three reasons for creating OSPF in a heirarchical design?
decrease routing overhead
speed up convergence
confine stability to single areas of the network
18. What is the administrative distance of OSPF?
110
19.
no auto summary
the network is considered discontigous because we have two classful network subnetted (on the left and right),
seperated by a different classful address.
if auto summarization is taking place, the routers cant determine which side is which because both sides would be summarized as
Class B, 172.16.0.0, which isnt specific enough to distinguish between the sides.
20. IF routers in a single area are configured with the same priority value, what value does a router use for the OSPF router ID in the absence of a loopback interface?
The highest IP of any PHSYICAL interface.
Trick question. Highest IP of any LOGICAL interface is an option. And is correct IF you had logical interfaces, but the question
states that any "logical interfaces are absent".
At OSPF startup, the highest IP of *any* active interface on the router becomes the OSPF router ID. If you have loopback (logical) interfaces configured,
one of them (the largest IP) will *override* the phsyical interfaces and the loopback IP becomes the RID.
Reference for which loopback (if multiple) wins:
packetpushers.net
------------------------------------------------------------------------------
END CHAPTER 9
41 hours 2-14 thru 2-28-22
original total 184 hours
14 hours review 12-26 thru 12-28-22
review total hours 46
book page 502/822
184 + 46 = 230 hours * 60 = (13,800 min) / 500 pages =
avg 28 min/page (includes reading and exercises/labs + online research)
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1. Describe the responsibilities of the IOS
network protocols and supporting functions
connecting traffic between devices
adding security to control access
providing scalability and reliablity
connecting traffic between devices
adding security to control access
providing scalability and reliablity
2. What are the options to connect to a Cisco device for management purposes?
console port
auxillary port
telnet
auxillary port
telnet
3. Understand the boot sequence of a router
POST, load IOS from flash memory, find the startup-config in NVRAM.
if no startup-config is present in NVRAM, the device enters setup mode
if no startup-config is present in NVRAM, the device enters setup mode
4. Describe the use of setup mode
starts automatically if no startup-config found in NVRAM.
Can also enter manually by typing setup from privileged mode
Can also enter manually by typing setup from privileged mode
5. Differentiate user, privileged, and global configuration modes,
both visually and from a command capabilities perspective
user mode AKA exec mode
routername>
very few available commands by default. Cannot view or change configuration
privilieged mode AKA priviliged exec mode
routername#
allows you to view and change configurations.
global configuration mode
routername(config)#
allows you to view and change GLOBAL configurations. and to reach other prompts (see below)
routername>
very few available commands by default. Cannot view or change configuration
privilieged mode AKA priviliged exec mode
routername#
allows you to view and change configurations.
global configuration mode
routername(config)#
allows you to view and change GLOBAL configurations. and to reach other prompts (see below)
6. Recognize addiional prompts available in other modes and describe their use
interface mode
routername(config-if)#
change interface settings
subinterface mode
routername(config-subif)#
change subinterface settings (logically divide a single physical interface)
line configuration mode
routername(config-line)#
set passwords and make other changes to various connection methods
line configuration mode
routername(config-router)#
enable and configure routing protocols
routername(config-if)#
change interface settings
subinterface mode
routername(config-subif)#
change subinterface settings (logically divide a single physical interface)
line configuration mode
routername(config-line)#
set passwords and make other changes to various connection methods
line configuration mode
routername(config-router)#
enable and configure routing protocols
7. Access and utilize editing and help features: question mark, command history, caret, hot keys
A question mark at the prompt will show a list of all available commands for that prompt:
Router# ?
Exec commands:
[OUTPUT CUT]
Filter command help by adding letters to the question mark:
Router# c?
Router#
c
note that the c remains in place; the system assumes you are going to use it
to find the next command in a string, type the first command with a question mark:
Router# clock ?
Router# clock set?
Router# clock set 11:15:11 ?
Router# clock set 11:15:11 25 april ?
Router# clock set 11:15:11 25 april 2011 ?
carriage return is the only remaining option for this command
Notice how the ? is not showing ALL required params; only showing the NEXT required param
ERRORS
Router# clock set 11:15:11
% incomplete command
not providing all required params
Router# sh serial 0/0/0
^
Invalid input detected a the '^' marker
not providing all required params
The problem here is that the full command is:
show interface serial 0/0/0
Router# sh ru
% Ambiguous command: "sh ru"
means there are multiple commands that being with the string youre using.
Use the question mark to find the command you want:
sh ru?
there are two commands that start with
show ru
Router# ?
Exec commands:
| access-enable | create a temporary access-list entry |
| access-profile | apply user-profile to interface |
| access-template | create a tempoary access-list entry |
| archive | manage archive files |
| auto | execl level automation |
| bfe | for manual emergency modes setting |
| calendar | manage the hardware calendar |
| cd | change current directory |
Filter command help by adding letters to the question mark:
Router# c?
| calendar | cd | clear | clock |
| cns | configure | connect | copy |
| crypto | ct-isdn |
note that the c remains in place; the system assumes you are going to use it
to find the next command in a string, type the first command with a question mark:
Router# clock ?
| read-calendar | read the hardware caleandar into the clock |
| set | set the date and time |
| update-calendar | Update the hardware caleander from the clock |
Router# clock set?
| hh:mm:ss | Current Time |
Router# clock set 11:15:11 ?
| <1-31> | Day of the month |
| MONTH | Month of the year |
Router# clock set 11:15:11 25 april ?
| <1993-2035> | year |
Router# clock set 11:15:11 25 april 2011 ?
| <cr> |
Notice how the ? is not showing ALL required params; only showing the NEXT required param
ERRORS
Router# clock set 11:15:11
% incomplete command
not providing all required params
Router# sh serial 0/0/0
^
Invalid input detected a the '^' marker
not providing all required params
The problem here is that the full command is:
show interface serial 0/0/0
Router# sh ru
% Ambiguous command: "sh ru"
means there are multiple commands that being with the string youre using.
Use the question mark to find the command you want:
sh ru?
| rudpv1 | running-conig |
8. Identify the information provided by the show version command
Router>
show version
Cisco IOS Software, C1900 Software (C1900-UNIVERSALK9-M), Version 15.1(4)M4, RELEASE SOFTWARE (fc2)
Technical Support: http://www.cisco.com/techsupport
Copyright (c) 1986-2007 by Cisco Systems, Inc.
Compiled Wed 23-Feb-11 14:19 by pt_team
describes the Cisco IOS running on the router
ROM: System Bootstrap, Version 15.1(4)M4, RELEASE SOFTWARE (fc1)
cisco1941 uptime is 1 minutes, 29 seconds
System returned to ROM by power-on
System image file is "flash0:c1900-universalk9-mz.SPA.151-1.M4.bin"
Last reload type: Normal Reload
describes the ROM used, which is used to boot the router and hold the POST
This product contains cryptographic features and is subject to United
States and local country laws governing import, export, transfer and
use. Delivery of Cisco cryptographic products does not imply
third-party authority to import, export, distribute or use encryption.
Importers, exporters, distributors and users are responsible for
compliance with U.S. and local country laws. By using this product you
agree to comply with applicable laws and regulations. If you are unable
to comply with U.S. and local laws, return this product immediately.
A summary of U.S. laws governing Cisco cryptographic products may be found at:
http://www.cisco.com/wwl/export/crypto/tool/stqrg.html
If you require further assistance please contact us by sending email to
export@cisco.com.
Cisco CISCO1941/K9 (revision 1.0) with 491520K/32768K bytes of memory.
Processor board ID FTX152400KS
2 Gigabit Ethernet interfaces
DRAM configuration is 64 bits wide with parity disabled.
255K bytes of non-volatile configuration memory.
249856K bytes of ATA System CompactFlash 0 (Read/Write)
License Info:
License UDI:
-------------------------------------------------
Device# PID SN
-------------------------------------------------
*0 CISCO1941/K9 FTX15241343-
Technology Package License Information for Module:'c1900'
----------------------------------------------------------------
Technology Technology-package Technology-package
Current Type Next reboot
-----------------------------------------------------------------
ipbase ipbasek9 Permanent ipbasek9
security None None None
data None None None
Configuration register is 0x2102
9. Set the hostname of a router
Router>
Router>enable
Router#configure terminal
Enter configuration commands, one per line. End with CNTL/Z.
Router(config)#hostname Michael
Michael(config)#
Router>
enable
Router# configure terminal
Enter configuration commands, one per line. End with CNTL/Z.
Router(config)# hostname Michael
Michael(config)#
10. Differentiate the enable password and enable secret password
Both passwords allow access to privileged exec mode
the enable secret password command is newer and always encrypted by default
if you set enable password and then set enable secret password, only the secret password will apply
to set a passowrd, provide it as an argument at the end of either commmand
the enable secret password command is newer and always encrypted by default
if you set enable password and then set enable secret password, only the secret password will apply
to set a passowrd, provide it as an argument at the end of either commmand
11. Descrbie the configuration and use of banners
Banners provide information to users accessing the device and can be displayed at various login prompts.
They are configured with the banner command and a keyword describing the specific type of banner
Enter TEXT message. End with the character '@'.
the '@' is the character I chose as delimiter to end the input-- required as third arg in the commmand
hi this is the motd banner 1-16-22 @
Michael(config)# exit
Michael#
%SYS-5-CONFIG_I: Configured from console by console
exit
Michael con0 is now available
Press RETURN to get started.
hi this is the motd banner 1-16-22
Michael>
They are configured with the banner command and a keyword describing the specific type of banner
Michael(config)#banner ?
login Set login banner
motd Set Message of the Day banner
Michael(config)#
banner motd @
Enter TEXT message. End with the character '@'.
the '@' is the character I chose as delimiter to end the input-- required as third arg in the commmand
hi this is the motd banner 1-16-22 @
Michael(config)# exit
Michael#
%SYS-5-CONFIG_I: Configured from console by console
exit
Michael con0 is now available
Press RETURN to get started.
hi this is the motd banner 1-16-22
Michael>
12. Set the enable secret on a router
Michael(config)#
enable secret 1234
note the word PASSWORD is not used for the secret command
note the word PASSWORD is not used for the secret command
13. Set the auxillary and console passwords on a router
User mode passwords are assigned by using the line command
There are three lines: aux, console, and vty
aux
set user-mode password for the auxillary port. Usually used for attaching modem to router, but can also be used as a console
Michael(config) line aux 0 (0 because there is only one aux port)
Michael(config-line) password aux1234
Michael(config-line) login enables login
console
set's a console user-mode password
Michael(config) line console 0 (0 because there is only one console port)
Michael(config-line) password console1234
Michael(config-line) login enables login
aux
set user-mode password for the auxillary port. Usually used for attaching modem to router, but can also be used as a console
Michael(config) line aux 0 (0 because there is only one aux port)
Michael(config-line) password aux1234
Michael(config-line) login enables login
console
set's a console user-mode password
Michael(config) line console 0 (0 because there is only one console port)
Michael(config-line) password console1234
Michael(config-line) login enables login
14. Set the Telnet password on a router (pg 230)
vty
sets a telnet user-mode password
Michael(config-line) line vty 0 ?
% Unrecognized command (help fails-- only works from configure terminal mode)
Michael(config-line) exit
Michael(config) line vty 0 ? find out the expected param, and as a bonus- how many lines you have (varies by device)
<1-1180> Last Line Number the command expects a FIRST and LAST line number
Michael(config) line vty 0 1180
Michael(config-line) password telnet1234 set the password
Michael(config-line) login enable login
NOTE if the telnet password isnt set, access will be denied:
Michael# telnet SFRouter
Tying SF Router (10.0.0.1)..Open
Passowrd required, but none set [Connection to SFRouter closed by foreing host]
Michael#
WORKAROUND- you can tell the router to allow Telnet connections without a password by using the no login command
Michael(config-line)# line vty 0 4
Michael(config-line)# no login
15. Describe the advantages of using Secure Shell and list its requirements
Uses encrypted keys to send data so that usernames and passwords are not sent in the clear.
It requires that a hostname and domain name be configured and that encryption keys be generated.
It requires that a hostname and domain name be configured and that encryption keys be generated.
16. Describe the process of preparing an interface for use
You must configure it with an IP address and subnet mask in the same subnet
of the hosts that will be connecting to the switch that is connected to
that interface.
It must be enabled with the no shutdown command
A serial interface that is connected back to back with another router serial interface must also be configured with a clock rate on the DCE end of the serial cable
It must be enabled with the no shutdown command
A serial interface that is connected back to back with another router serial interface must also be configured with a clock rate on the DCE end of the serial cable
17. Understand how to troubleshoot a serial link problem
show interface serial 0
down, line protocol is down
indicates physical layer problem
show interface serial 0
up, line protocol is down
indicates link layer problem problem
down, line protocol is down
indicates physical layer problem
show interface serial 0
up, line protocol is down
indicates link layer problem problem
18. Understand how to verify your router with the show interfaces command
shows the statistics for the interfaces on the router, if they are shut down,
and what their ip addresses are.
Michael#show interfaces GigabitEthernet0/0 is administratively down, line protocol is down (disabled) Hardware is CN Gigabit Ethernet, address is 00d0.bca2.9601 (bia 00d0.bca2.9601) MTU 1500 bytes, BW 1000000 Kbit, DLY 10 usec, reliability 255/255, txload 1/255, rxload 1/255 Encapsulation ARPA, loopback not set Keepalive set (10 sec) Full-duplex, 100Mb/s, media type is RJ45 output flow-control is unsupported, input flow-control is unsupported ARP type: ARPA, ARP Timeout 04:00:00, Last input 00:00:08, output 00:00:05, output hang never Last clearing of "show interface" counters never Input queue: 0/75/0 (size/max/drops); Total output drops: 0 Queueing strategy: fifo Output queue :0/40 (size/max) 5 minute input rate 0 bits/sec, 0 packets/sec 5 minute output rate 0 bits/sec, 0 packets/sec 0 packets input, 0 bytes, 0 no buffer Received 0 broadcasts, 0 runts, 0 giants, 0 throttles 0 input errors, 0 CRC, 0 frame, 0 overrun, 0 ignored, 0 abort 0 watchdog, 1017 multicast, 0 pause input 0 input packets with dribble condition detected 0 packets output, 0 bytes, 0 underruns 0 output errors, 0 collisions, 1 interface resets 0 unknown protocol drops 0 babbles, 0 late collision, 0 deferred 0 lost carrier, 0 no carrier 0 output buffer failures, 0 output buffers swapped out GigabitEthernet0/1 is administratively down, line protocol is down (disabled) Hardware is CN Gigabit Ethernet, address is 00d0.bca2.9602 (bia 00d0.bca2.9602) MTU 1500 bytes, BW 1000000 Kbit, DLY 10 usec, reliability 255/255, txload 1/255, rxload 1/255 Encapsulation ARPA, loopback not set Keepalive set (10 sec) Full-duplex, 100Mb/s, media type is RJ45 output flow-control is unsupported, input flow-control is unsupported ARP type: ARPA, ARP Timeout 04:00:00, Last input 00:00:08, output 00:00:05, output hang never Last clearing of "show interface" counters never Input queue: 0/75/0 (size/max/drops); Total output drops: 0 Queueing strategy: fifo Output queue :0/40 (size/max) 5 minute input rate 0 bits/sec, 0 packets/sec 5 minute output rate 0 bits/sec, 0 packets/sec 0 packets input, 0 bytes, 0 no buffer Received 0 broadcasts, 0 runts, 0 giants, 0 throttles 0 input errors, 0 CRC, 0 frame, 0 overrun, 0 ignored, 0 abort 0 watchdog, 1017 multicast, 0 pause input 0 input packets with dribble condition detected 0 packets output, 0 bytes, 0 underruns 0 output errors, 0 collisions, 1 interface resets 0 unknown protocol drops 0 babbles, 0 late collision, 0 deferred 0 lost carrier, 0 no carrier 0 output buffer failures, 0 output buffers swapped out Vlan1 is administratively down, line protocol is down Hardware is CPU Interface, address is 00d0.ff77.0c9a (bia 00d0.ff77.0c9a) MTU 1500 bytes, BW 100000 Kbit, DLY 1000000 usec, reliability 255/255, txload 1/255, rxload 1/255 Encapsulation ARPA, loopback not set ARP type: ARPA, ARP Timeout 04:00:00 Last input 21:40:21, output never, output hang never Last clearing of "show interface" counters never Input queue: 0/75/0/0 (size/max/drops/flushes); Total output drops: 0 Queueing strategy: fifo Output queue: 0/40 (size/max) 5 minute input rate 0 bits/sec, 0 packets/sec 5 minute output rate 0 bits/sec, 0 packets/sec 1682 packets input, 530955 bytes, 0 no buffer Received 0 broadcasts (0 IP multicast) 0 runts, 0 giants, 0 throttles 0 input errors, 0 CRC, 0 frame, 0 overrun, 0 ignored 563859 packets output, 0 bytes, 0 underruns 0 output errors, 23 interface resets 0 output buffer failures, 0 output buffers swapped out
19. Describe how to view, edit, delete, and save a configuration
show running-config
show startup-config
copy running-config startup-config
erase startup-config
show startup-config
copy running-config startup-config
erase startup-config
1. What command is used to set a serial interface to provide clocking to another router at 64kb?
router(config)
clock rate 64000
2. If you telnet into a router and get the response connection refused, password not set, what
commands would you execute on the destination router to stop receiving this message and not
be prompted for a password?
router(config)#
line vty ?
<0-15> First Line number
router(config)# line vty 0 15
router(config-line)# no login
<0-15> First Line number
router(config)# line vty 0 15
router(config-line)# no login
3. If you type show inter ethernet 0 and notice the port is administratively down,
what commands would you execute to enable the interface?
router#
show interfaces
GigabitEthernet0/0/0 is administratively down, line protocol is down (disabled)
[output cut]
GigabitEthernet0/0/1 is administratively down, line protocol is down (disabled)
[output cut]
GigabitEthernet0/0/2 is administratively down, line protocol is down (disabled)
[output cut]
Vlan1 is administratively down, line protocol is down
[output cut]
router# show interface gigabitethernet 0/0/0
GigabitEthernet0/0/0 is administratively down, line protocol is down (disabled)
[output cut]
router# configure terminal
router(conf)# interface gigabitethernet 0/0/0
router(conf-if)# no shutdown
%LINK-5-CHANGED: Interface GigabitEthernet0/0/0, changed state to up
router(conf-if)# do show int g0/0/0
GigabitEthernet0/0/0 is up, line protocol is down (disabled)
[output cut]
GigabitEthernet0/0/0 is administratively down, line protocol is down (disabled)
[output cut]
GigabitEthernet0/0/1 is administratively down, line protocol is down (disabled)
[output cut]
GigabitEthernet0/0/2 is administratively down, line protocol is down (disabled)
[output cut]
Vlan1 is administratively down, line protocol is down
[output cut]
router# show interface gigabitethernet 0/0/0
GigabitEthernet0/0/0 is administratively down, line protocol is down (disabled)
[output cut]
router# configure terminal
router(conf)# interface gigabitethernet 0/0/0
router(conf-if)# no shutdown
%LINK-5-CHANGED: Interface GigabitEthernet0/0/0, changed state to up
router(conf-if)# do show int g0/0/0
GigabitEthernet0/0/0 is up, line protocol is down (disabled)
[output cut]
4. If you wanted to delete the configuration store in NVRAM, what command to use?
router#
erase ?
startup-config Erase contents of configuration memory
router# erase startup-config
Erasing the nvram filesystem will remove all configuration files! Continue? [confirm]
[OK]
Erase of nvram: complete
%SYS-7-NV_BLOCK_INIT: Initialized the geometry of nvram
router#
startup-config Erase contents of configuration memory
router# erase startup-config
Erasing the nvram filesystem will remove all configuration files! Continue? [confirm]
[OK]
Erase of nvram: complete
%SYS-7-NV_BLOCK_INIT: Initialized the geometry of nvram
router#
5. If you wanted to set the user-mode password to todd for the console port,
what command to use?
router#
configure terminal
router(conf)# line console 0 there is only one console port, "0"
router(conf)# login tells the port to prompt for authentication
note that this will not work properly unless you also apply a password
router(conf)# password todd
router(conf)# line console 0 there is only one console port, "0"
router(conf)# login tells the port to prompt for authentication
note that this will not work properly unless you also apply a password
router(conf)# password todd
6. If you wanted to set the enable secret password to cisco, what command to use?
router#
configure terminal
router(conf-t)# enable secret cisco
router(conf-t)# enable secret cisco
7. If you want to determine if serial interface 0/2 should provide clocking, what command to use?
router#
show controllers ?
packet tracer 4300 router not giving output
Ethernet IEEE 802.3
FastEthernet FastEthernet IEEE 802.3
GigabitEthernet GigabitEthernet IEEE 802.3z
Serial Serial
<cr>
router#
show controllers serial 0/2
packet tracer 4300 router not giving output
8. What command would you use to see the terminal size history?
router#
show terminal
Line 0, Location: , Type:
Length: 24 lines, Width: 80 columns
Baud rate (TX/RX) is 9600/9600, no parity, 1 stopbits, 8 databits
Status: PSI Enabled, Ready, Active, Automore On
Capabilities: none
Modem state: Ready
Modem hardware state: CTS* noDSR DTR RTS
Special Chars: Escape Hold Stop Start Disconnect Activation
^^x none - - none
Timeouts: Idle EXEC Idle Session Modem Answer Session Dispatch
00:10:00 never none not set
Idle Session Disconnect Warning
never
Login-sequence User Response
00:00:30
Autoselect Initial Wait
not set
Modem type is unknown.
Session limit is not set.
Time since activation: 00:03:04
Editing is enabled.
History is enabled, history size is 10.
DNS resolution in show commands is enabled
Full user help is disabled
Allowed input transports are All.
Allowed output transports are pad telnet rlogin.
Preferred transport is telnet.
No output characters are padded
No special data dispatching characters
9. You want to reinitizalize the router and totally replace the running-config with
the current startup-config. What command to use?
router#
reload
System configuration has been modified. Save? [yes/no]:
Proceed with reload? [confirm]
System configuration has been modified. Save? [yes/no]:
Proceed with reload? [confirm]
Initializing Hardware ...
Checking for PCIe device presence...done
System integrity status: 0x610
Rom image verified correctly
System Bootstrap, Version 16.7(3r), RELEASE SOFTWARE
Copyright (c) 1994-2018 by cisco Systems, Inc.
Current image running: Boot ROM0
Last reset cause: LocalSoft
Cisco ISR4331/K9 platform with 4194304 Kbytes of main memory
no valid BOOT image found
Final autoboot attempt from default boot device...
Located isr4300-universalk9.16.06.04.SPA.bin
############################
Package header rev 1 structure detected
IsoSize = 550114467
Calculating SHA-1 hash...Validate package: SHA-1 hash:
calculated 444F4D02:44C58887:D9C8942B:C557D3CF:2A14247E
expected 444F4D02:44C58887:D9C8942B:C557D3CF:2A14247E
RSA Signed RELEASE Image Signature Verification Successful.
Image validated
Restricted Rights Legend
Use, duplication, or disclosure by the Government is
subject to restrictions as set forth in subparagraph
(c) of the Commercial Computer Software - Restricted
Rights clause at FAR sec. 52.227-19 and subparagraph
(c) (1) (ii) of the Rights in Technical Data and Computer
Software clause at DFARS sec. 252.227-7013.
cisco Systems, Inc.
170 West Tasman Drive
San Jose, California 95134-1706
Cisco IOS Software[Everest], ISR Software(X86_64_LINUX_IOSD - UNIVERSALK9 - M), Version 16.6.4, RELEASE SOFTWARE(fc3)
Technical Support : http://www.cisco.com/techsupport
Copyright(c) 1986 - 2018 by Cisco Systems, Inc.
Compiled Sun 08 - Jul - 18 04:33 by mcpre
Cisco IOS - XE software, Copyright(c) 2005 - 2018 by cisco Systems, Inc.
All rights reserved.Certain components of Cisco IOS - XE software are
licensed under the GNU General Public License("GPL") Version 2.0.The
software code licensed under GPL Version 2.0 is free software that comes
with ABSOLUTELY NO WARRANTY.You can redistribute and / or modify such
GPL code under the terms of GPL Version 2.0.For more details, see the
documentation or "License Notice" file accompanying the IOS - XE software,
or the applicable URL provided on the flyer accompanying the IOS - XE
software.
This product contains cryptographic features and is subject to United
States and local country laws governing import, export, transfer and
use. Delivery of Cisco cryptographic products does not imply
third-party authority to import, export, distribute or use encryption.
Importers, exporters, distributors and users are responsible for
compliance with U.S. and local country laws. By using this product you
agree to comply with applicable laws and regulations. If you are unable
to comply with U.S. and local laws, return this product immediately.
A summary of U.S. laws governing Cisco cryptographic products may be found at:
http://www.cisco.com/wwl/export/crypto/tool/stqrg.html
If you require further assistance please contact us by sending email to
export@cisco.com.
cisco ISR4331/K9 (1RU) processor with 1795999K/6147K bytes of memory.
Processor board ID FLM232010G0
3 Gigabit Ethernet interfaces
32768K bytes of non-volatile configuration memory.
4194304K bytes of physical memory.
3207167K bytes of flash memory at bootflash:.
0K bytes of WebUI ODM Files at webui:.
--- System Configuration Dialog ---
Would you like to enter the initial configuration dialog? [yes/no]:
10. How would you set the name of a router to Chicago?
router#
configure terminal
router(config)# hostname Chicago
Chicago(config)#
router(config)# hostname Chicago
Chicago(config)#
Hands-on Lab 6.1 Erasing an Existing Configuration
router>
enable
router#
erase startup-config
Erasing the nvram filesystem will remove all configuration files! Continue? [confirm]
[OK]
Erase of nvram: complete
%SYS-7-NV_BLOCK_INIT: Initialized the geometry of nvram
router#
Hands-on Lab 6.2 Exploring User, Privileged, and Configuration Modes
user mode
router>
?
<1-99> Session number to resume
connect Open a terminal connection
disable Turn off privileged commands
disconnect Disconnect an existing network connection
enable Turn on privileged commands
exit Exit from the EXEC
logout Exit from the EXEC
ping Send echo messages
resume Resume an active network connection
show Show running system information
ssh Open a secure shell client connection
telnet Open a telnet connection
terminal Set terminal line parameters
traceroute Trace route to destination
user mode
router>
enable
privileged exec mode
router#
?
<1-99> Session number to resume
auto Exec level Automation
clear Reset functions
clock Manage the system clock
configure Enter configuration mode
connect Open a terminal connection
copy Copy from one file to another
debug Debugging functions (see also 'undebug')
delete Delete a file
dir List files on a filesystem
disable Turn off privileged commands
disconnect Disconnect an existing network connection
enable Turn on privileged commands
erase Erase a filesystem
exit Exit from the EXEC
logout Exit from the EXEC
mkdir Create new directory
more Display the contents of a file
no Disable debugging informations
ping Send echo messages
reload Halt and perform a cold restart
resume Resume an active network connection
rmdir Remove existing directory
send Send a message to other tty lines
setup Run the SETUP command facility
show Show running system information
ssh Open a secure shell client connection
telnet Open a telnet connection
terminal Set terminal line parameters
traceroute Trace route to destination
undebug Disable debugging functions (see also 'debug')
vlan Configure VLAN parameters
write Write running configuration to memory, network, or terminal
router#
config
Configuring from terminal, memory, or network [terminal]?
terminal is the default, enter to select
router(config)#
?
aaa Authentication, Authorization and Accounting.
access-list Add an access list entry
banner Define a login banner
bba-group Configure BBA Group
boot Modify system boot parameters
cdp Global CDP configuration subcommands
class-map Configure Class Map
clock Configure time-of-day clock
config-register Define the configuration register
crypto Encryption module
default Set a command to its defaults
do To run exec commands in config mode
dot11 IEEE 802.11 config commands
enable Modify enable password parameters
end Exit from configure mode
exit Exit from configure mode
flow Global Flow configuration subcommands
hostname Set system's network name
interface Select an interface to configure
ip Global IP configuration subcommands
ipv6 Global IPv6 configuration commands
key Key management
license Configure license features
line Configure a terminal line
lldp Global LLDP configuration subcommands
logging Modify message logging facilities
login Enable secure login checking
mac-address-table Configure the MAC address table
no Negate a command or set its defaults
ntp Configure NTP
parser Configure parser
policy-map Configure QoS Policy Map
port-channel EtherChannel configuration
priority-list Build a priority list
privilege Command privilege parameters
queue-list Build a custom queue list
radius RADIUS server configuration command
radius-server Modify Radius query parameters
router Enable a routing process
secure Secure image and configuration archival commands
security Infra Security CLIs
service Modify use of network based services
snmp-server Modify SNMP engine parameters
spanning-tree Spanning Tree Subsystem
tacacs-server Modify TACACS query parameters
username Establish User Name Authentication
vpdn Virtual Private Dialup Network
vpdn-group VPDN group configuration
router(conf)#
interface g0/0/0
router(conf-if)#
?
arp Set arp type (arpa, probe, snap) or timeout
bandwidth Set bandwidth informational parameter
cdp CDP interface subcommands
channel-group Add this interface to an Etherchannel group
crypto Encryption/Decryption commands
custom-queue-list Assign a custom queue list to an interface
delay Specify interface throughput delay
description Interface specific description
duplex Configure duplex operation.
exit Exit from interface configuration mode
fair-queue Enable Fair Queuing on an Interface
hold-queue Set hold queue depth
ip Interface Internet Protocol config commands
ipv6 IPv6 interface subcommands
lldp LLDP interface subcommands
mac-address Manually set interface MAC address
media-type Configure media type
mtu Set the interface Maximum Transmission Unit (MTU)
no Negate a command or set its defaults
pppoe pppoe interface subcommands
pppoe-client pppoe client
priority-group Assign a priority group to an interface
service-policy Configure QoS Service Policy
shutdown Shutdown the selected interface
speed Configure speed operation.
standby HSRP interface configuration commands
tx-ring-limit Configure PA level transmit ring limit
router(conf-if)#
exit
back one level
router(conf)#
exit
back one level
router#
disable
back to user mode
router>
Hands-on Lab 6.3 Using the Help and Editing Features
router#
?
router#
cl?
clear clock
router#
clock ?
set Set the date and time
router#
clock set 10:30:30 ?
<1-31> Day of the month
MONTH Month of the year
router#
clock set 10:30:30 17 January 2022
router#
router#
show clock
10:31:33.95 UTC Mon Jan 17 2022
keyboard commands
ctrl + A
beginning of line
ctrl + E
end of line
ctrl + B
back one character
ctrl + F
forward one character
ctrl + P
paste previous command
TAB
complete a partially typed command
router#
terminal no editing
turns off the keyboard shortcuts
router#
terminal editing
turns on the keyboard shortcuts
router#
show history
shows last 10 commands by default
router#
terminal history size 20
sets the history size to 20
Hands-on Lab 6.4 Saving a Router Configuration
router#
show startup-config
"startup config" AKA NVRAM
Using 672 bytes
!
version 16.6.4
no service timestamps log datetime msec
no service timestamps debug datetime msec
no service password-encryption
!
hostname Router
!
!
!
!
!
!
!
!
no ip cef
no ipv6 cef
!
!
!
!
!
!
!
!
!
!
!
!
spanning-tree mode pvst
!
!
!
!
!
!
interface GigabitEthernet0/0/0
no ip address
duplex auto
speed auto
shutdown
!
interface GigabitEthernet0/0/1
no ip address
duplex auto
speed auto
shutdown
!
interface GigabitEthernet0/0/2
no ip address
duplex auto
speed auto
shutdown
!
interface Vlan1
no ip address
shutdown
!
ip classless
!
ip flow-export version 9
!
!
!
!
!
!
!
!
line con 0
!
line aux 0
!
line vty 0 4
login
line vty 5 15
login
!
!
!
end
to copy a running config to NVRAM:
router#
copy running-config startup-config
to erase NVRAM:
router#
erase startup-config
router#
erase startup-config
Erasing the nvram filesystem will remove all configuration files! Continue? [confirm]
[OK]
Erase of nvram: complete
%SYS-7-NV_BLOCK_INIT: Initialized the geometry of nvram
router#
show startup-config
startup-config is not present
router#
reload
Proceed with reload? [confirm]
[output cut]
Would you like to enter the initial configuration dialog? [yes/no]:
Hands-on Lab 6.5 Setting Passwords
add a secret password
router(config)#
enable secret 1234
remove the secret password
router(config)#
no enable secret
Note youre not prompted for the secret, since you already had to provide
it in order to enter conf mode
add a regular password
router(config)#
enable password 4321
Can coexist with the secret password, but the two passwords must be different
----------------------------------------------------------------------
add password for Telnet aka VTY
router(config)#
line vty 0 15
16 virtual telnet lines on this router
We can set the whole range, a portion of the range, or a single line
router(config)#
login activate authentication
router(config)#
password telnet123
----------------------------------------------------------------------
add password for Auxiliary
router(config)#
line aux 0 there's only sone aux line
router(config)#
login activate authentication
router(config)#
password aux123
----------------------------------------------------------------------
add password for Console
router(config)#
line console 0 there's only one console line
router(config)#
login activate authentication
router(config)#
password console123
router(config)#
exec-timeout 0 0 min/sec
stop the console from timing out and logging you out
router(config)#
logging synchronous
dont overwrite input commands with console messages
Hands-on Lab 6.6 Setting the Hostname, Descriptions, IP Address, and Clock Rate
set router name
router(config)#
hostname routerA
------------------------------------------
set motd banner
routerA(config)#
banner ?
login Set login banner
motd Set Message of the Day banner
router(config)#
banner motd #
Enter TEXT message. End with the character '#'.
welcome to the router #
router(config)#
------------------------------------------
remove the banner
router(config)#
no banner motd
------------------------------------------
set login banner
router(config)#
banner login #
Enter TEXT message. End with the character '#'.
please login now #
router(config)#
------------------------------------------
add an IP address to an interface
router(config)#
do show interfaces use "do" to enable this command within config mode
GigabitEthernet0/0/0 is administratively down, line protocol is down (disabled)
---cut---
GigabitEthernet0/0/1 is administratively down, line protocol is down (disabled)
---cut---
GigabitEthernet0/0/2 is administratively down, line protocol is down (disabled)
---cut---
Vlan1 is administratively down, line protocol is down
router(config)#
interface g0/0/0
router(config-if)#
ip address 1.1.1.1 255.255.0.0
router(config-if)#
no shutdown
%LINK-5-CHANGED: Interface GigabitEthernet0/0/0, changed state to up
router(config-if)#
do show interfaces
GigabitEthernet0/0/0 is up, line protocol is down (disabled)
Internet address is 1.1.1.1/16
router(config-if)#
description WAN link to Miami
Chapter 6 Review Questions
1. You type show running-config and get this output:
---cut---
line console 0
Exec-timeout 1 44
Password 7 098C0BQR
Login
---cut---
What do the two numbers following the exec-timeout command mean?
minutes and seconds
2. Which connection method for connecting to a router is considered "out-of-band"?
auxiliary
The aux port can be configured to allow a modem to connect to the router.
It lets you dial up to a remote router in order to connect to the aux port if the router is down.
This method is considered "out of band" since its not connecting via "the network"
3. Which two commands are required when configuring SSH on your router?
ip domain-name name
username name password password
Example: Using SSH instead of Telnet
set your hostname, domain, and username
router(config)#
hostname Dallas
Dallas(config)#
ip domain-name Lammle.com
Dallas(config)#
username Michael password 1234
generate encryption keys
Dallas(config)#
crypto key generate rsa genral-keys modulus 1024
The name for the keys will be Michael.Lammle.com
% The key modulus size is 1024 bits
% Generating 1024 bit RSA keys, keys will be non-exportable...[ok]
*June 24 19:25:30.035: %SSH-5-ENABLED: SSH 1.99 has been enabled
enable SSH version 2
router(config)#
ssh version 2
connect to the vty lines of the router
router(config)#
line vty 0 1180
configure SSH and then Telnet as access protocols
router(config-line)#
transport input ssh telnet
4. Which command will show you wheter a DTE or a DCE cable is plugged into serial 0?
show controllers serial 0
will show whether DTE or DCE cable is connected to the interface
NOTE if it is a DTE connection you must add clocking with the
clock rate command
5. Which is a correct combination of file type and default location on a Cisco router?
IOS- flash memory
startup config- NVRAM
running config- RAM
6. You set the console password, but when you display the configuration, the password doesn't show up;
it looks like this:
[output cut]
line console 0
Exec-timeout 1 44
Password 7 098C0BQR
Login
[output cut]
What command would configure the password to be stored this way?
service password-encryption
7. Which command will configure all the default VTY ports on a router?
from global config mode:
line vty 0 4
will set all 5 default lines
8. Which command set the secret password to Cisco?
enable secret Cisco
9. If you wanted to see a message when logging into the router, which command would you use?
MOTD
10. Which prompt indicate that the router is currently in priviliged mode?
router#
11. What command do you type to save the configuration stored in RAM to NVRAM?
copy running-config startup-config
12. You try to telnet into SSFRouter from router to Corp and receive this message:
Corp#telnet SFRouter
Trying SFRouter (10.0.0.1)...Open
Password required, but none set
[Connection to SFRouter closed by foreing host]
Corp#
Which command sequence will address the problem correctly?
SFRouter(config)#
line vty 0 4
SFRouter(config-line)#
password password1234
SFRouter(config-line)#
login
13. Which command will delete the contents of NVRAM on a router?
erase startup-config
14. What is the problem with an interface if you type
show interface serial 9
and receive the following message?
Serial0 is administratively down, line protocol is down
is set to 'shut' by default, fix with no shut
15. Which command displays the configurable parameters and statistics of all interfaces on a router?
show interfaces
16. If you delete the contents of NVRAM and reboot the router, what mode will you be in?
setup mode
--- System Configuration Dialog ---
Would you like to enter the initial configuration dialog? [yes/no]:
17. You type the following command into the router and receive the following output:
Router#show serial 0/0
^
% Invalid input detected at '^' marker.
show interface serial 0/0
18. You type Router#sh ru and receive a % ambiguous command error.
Why did you receive this error?
not specific enough- there is more than one possible
show
command that starts with
ru
19. Which of the following commands will display the current
IP addressing and the layer 1 and 2 status of an interface?
show interfaces
GigabitEthernet0/0/0 is up, line protocol is down (disabled)
Hardware is ISR4331-3x1GE, address is 000d.bd45.db01 (bia 000d.bd45.db01)
Internet address is 1.1.1.1/16
MTU 1500 bytes, BW 1000000 Kbit, DLY 10 usec,
reliability 255/255, txload 1/255, rxload 1/255
Encapsulation ARPA, loopback not set
Keepalive not supported
Half Duplex, 1000Mbps, link type is auto, media type is Auto Select
output flow-control is on, input flow-control is on
ARP type: ARPA, ARP Timeout 04:00:00,
Last input 00:00:08, output 00:00:05, output hang never
Last clearing of "show interface" counters never
Input queue: 0/375/0 (size/max/drops); Total output drops: 0
Queueing strategy: fifo
Output queue :0/40 (size/max)
5 minute input rate 0 bits/sec, 0 packets/sec
5 minute output rate 0 bits/sec, 0 packets/sec
0 packets input, 0 bytes, 0 no buffer
Received 0 broadcasts (0 IP multicasts)
0 runts, 0 giants, 0 throttles
0 input errors, 0 CRC, 0 frame, 0 overrun, 0 ignored
0 watchdog, 1017 multicast, 0 pause input
0 input packets with dribble condition detected
0 packets output, 0 bytes, 0 underruns
0 output errors, 0 collisions, 1 interface resets
0 unknown protocol drops
0 babbles, 0 late collision, 0 deferred
0 lost carrier, 0 no carrier
0 output buffer failures, 0 output buffers swapped out
GigabitEthernet0/0/1 is administratively down, line protocol is down (disabled)
Hardware is ISR4331-3x1GE, address is 000d.bd45.db02 (bia 000d.bd45.db02)
MTU 1500 bytes, BW 1000000 Kbit, DLY 10 usec,
reliability 255/255, txload 1/255, rxload 1/255
Encapsulation ARPA, loopback not set
Keepalive not supported
output flow-control is on, input flow-control is on
ARP type: ARPA, ARP Timeout 04:00:00,
Last input 00:00:08, output 00:00:05, output hang never
Last clearing of "show interface" counters never
Input queue: 0/375/0 (size/max/drops); Total output drops: 0
Queueing strategy: fifo
Output queue :0/40 (size/max)
5 minute input rate 0 bits/sec, 0 packets/sec
5 minute output rate 0 bits/sec, 0 packets/sec
0 packets input, 0 bytes, 0 no buffer
Received 0 broadcasts (0 IP multicasts)
0 runts, 0 giants, 0 throttles
0 input errors, 0 CRC, 0 frame, 0 overrun, 0 ignored
0 watchdog, 1017 multicast, 0 pause input
0 input packets with dribble condition detected
0 packets output, 0 bytes, 0 underruns
0 output errors, 0 collisions, 1 interface resets
0 unknown protocol drops
0 babbles, 0 late collision, 0 deferred
0 lost carrier, 0 no carrier
0 output buffer failures, 0 output buffers swapped out
GigabitEthernet0/0/2 is administratively down, line protocol is down (disabled)
Hardware is ISR4331-3x1GE, address is 000d.bd45.db03 (bia 000d.bd45.db03)
MTU 1500 bytes, BW 1000000 Kbit, DLY 10 usec,
reliability 255/255, txload 1/255, rxload 1/255
Encapsulation ARPA, loopback not set
Keepalive not supported
Half Duplex, 1000Mbps, link type is auto, media type is unknown media type
output flow-control is on, input flow-control is on
ARP type: ARPA, ARP Timeout 04:00:00,
Last input 00:00:08, output 00:00:05, output hang never
Last clearing of "show interface" counters never
Input queue: 0/375/0 (size/max/drops); Total output drops: 0
Queueing strategy: fifo
Output queue :0/40 (size/max)
5 minute input rate 0 bits/sec, 0 packets/sec
5 minute output rate 0 bits/sec, 0 packets/sec
0 packets input, 0 bytes, 0 no buffer
Received 0 broadcasts (0 IP multicasts)
0 runts, 0 giants, 0 throttles
0 input errors, 0 CRC, 0 frame, 0 overrun, 0 ignored
0 watchdog, 1017 multicast, 0 pause input
0 input packets with dribble condition detected
0 packets output, 0 bytes, 0 underruns
0 output errors, 0 collisions, 1 interface resets
0 unknown protocol drops
0 babbles, 0 late collision, 0 deferred
0 lost carrier, 0 no carrier
0 output buffer failures, 0 output buffers swapped out
Vlan1 is administratively down, line protocol is down
Hardware is CPU Interface, address is 00d0.9715.9967 (bia 00d0.9715.9967)
MTU 1500 bytes, BW 100000 Kbit, DLY 1000000 usec,
reliability 255/255, txload 1/255, rxload 1/255
Encapsulation ARPA, loopback not set
ARP type: ARPA, ARP Timeout 04:00:00
Last input 21:40:21, output never, output hang never
Last clearing of "show interface" counters never
Input queue: 0/75/0/0 (size/max/drops/flushes); Total output drops: 0
Queueing strategy: fifo
Output queue: 0/40 (size/max)
5 minute input rate 0 bits/sec, 0 packets/sec
5 minute output rate 0 bits/sec, 0 packets/sec
1682 packets input, 530955 bytes, 0 no buffer
Received 0 broadcasts (0 IP multicast)
0 runts, 0 giants, 0 throttles
0 input errors, 0 CRC, 0 frame, 0 overrun, 0 ignored
563859 packets output, 0 bytes, 0 underruns
0 output errors, 23 interface resets
0 output buffer failures, 0 output buffers swapped out
show ip interface
GigabitEthernet0/0/0 is up, line protocol is down (disabled)
Internet address is 1.1.1.1/16
Broadcast address is 255.255.255.255
Address determined by setup command
MTU is 1500 bytes
Helper address is not set
Directed broadcast forwarding is disabled
Outgoing access list is not set
Inbound access list is not set
Proxy ARP is enabled
Security level is default
Split horizon is enabled
ICMP redirects are always sent
ICMP unreachables are always sent
ICMP mask replies are never sent
IP fast switching is disabled
IP fast switching on the same interface is disabled
IP Flow switching is disabled
IP Fast switching turbo vector
IP multicast fast switching is disabled
IP multicast distributed fast switching is disabled
Router Discovery is disabled
IP output packet accounting is disabled
IP access violation accounting is disabled
TCP/IP header compression is disabled
RTP/IP header compression is disabled
Probe proxy name replies are disabled
Policy routing is disabled
Network address translation is disabled
BGP Policy Mapping is disabled
Input features: MCI Check
WCCP Redirect outbound is disabled
WCCP Redirect inbound is disabled
WCCP Redirect exclude is disabled
GigabitEthernet0/0/1 is administratively down, line protocol is down (disabled)
Internet protocol processing disabled
GigabitEthernet0/0/2 is administratively down, line protocol is down (disabled)
Internet protocol processing disabled
Vlan1 is administratively down, line protocol is down
Internet protocol processing disabled
20. At which layer of the OSI model would you assume the problem is if you type
show interface serial 1
and receive the following message?
Serial 1 is down, line protocol is down
physical
if you see both interface and protocal down, it's physical
if you see serial1 is up but line protocol down, its data link- data-link keepalives are not being sent from the remote end
END CHAPTER 6
15 hours 1-15 thru 1-19-22
original total hours 63
2.5 hours review 12-21-22
review total hours 13.5
book page 274/822
Chapter 7 Notes - Managing a Cisco Internetwork
notes
Configuration Register
16 bits / 2 bytes... bit values from 15 to 0
uses Hexadecimal nibbles
Chapter 7 Exam Essentials - Managing a Cisco Internetwork
1. Define the Cisco router componenets
ROM
- used to start and maintain the router. Holds bootstrap, POST, mini-IOS
bootstrap
- stored in the microcode of the ROM. Finds where the IOS program is located and loads the file.
POST
- stored in the microcode of the ROM. Used to check the basic funtionality and determine which interfaces are present
ROM monitor
- stored in the microcode of the ROM. Used for manufacturing, testing, and troubleshooting
mini-IOS
- Called the RXBOOT or 'bootloader'. It's a small OS in ROM that can be used to bring up an interface and load a Cisco IOS into flash memory
-----------------------------------------------------------------------------------------------------------------------
flash memory
- EEPROM- default location of the IOS
NVRAM
-holds the router/switch configuration
not erased when the device is reloaded
configuration register
- controls how the router boots up
Tells the router to load the IOS from flash memory as well as to load the configuration from NVRAM
RAM
- used to hold packet buffers, ARP cache, routing tables and the data structures that allow the router to function.
running-config is stored in RAM
routers expand the IOS from flash into RAM at boot
2. Identify the steps in the router boot sequence
POST
bootstrap
load the IOS from flash into RAM
load the configuration file from NVRAM into RAM
running-config and the IOS are both now running in RAM
3. Understand configuration register commands and settings
0x2102 default- find the boot sequence in NVRAM
0x2101 boot from ROM
0x2142 do not load the startup-config in NVRAM. Used for password recovery
4.Perform password recovery
NOTE - this requires physical access to reboot the router
The default configuration register value is 0x2102 which tells the router to load a config stored
in NVRAM(startup-config).
To recover a password, we need to change the config register value to 0x2142 which tells the router to ignore the VRAM contents and load a 'non configured' OS.
"configurations" can be defined as any changes we make to the device: hostname, passwords, interfaces, etc
For this demo, our 4331 router is configured with the hostname 4331 and the password 1234
4331(config)#
enable secret 1234
4331#
copy run start
Destination filename [startup-config]?
Building configuration...
[OK]
Step 1. Bounce the router, then interrupt the boot sequence by performing a break.
Initializing Hardware ...
Checking for PCIe device presence...done
System integrity status: 0x610
Rom image verified correctly
System Bootstrap, Version 16.7(3r), RELEASE SOFTWARE
Copyright (c) 1994-2018 by cisco Systems, Inc.
Current image running: Boot ROM0
Last reset cause: LocalSoft
Cisco ISR4331/K9 platform with 4194304 Kbytes of main memory
no valid BOOT image found
Final autoboot attempt from default boot device...
Located isr4300-universalk9.16.06.04.SPA.bin
###############################################################
CTRL+BREAK
monitor: command "boot" aborted due to user interrupt
rommon 1 >
Step 2. We're given a ROM MONITOR prompt which allows us to change the configuration register (Cisco ISR/2600 Series commands).
rommon 1 >
confreg 0x2142
rommon 1 >
reset must reset or power cycle router to apply the change
system will ask if you want Setup Mode - that is the the generic startup message,
since we are bypassing the startup configuration. Our answer is no.--- System Configuration Dialog ---
Would you like to enter the initial configuration dialog? [yes/no]:
N + Enter
we now have full access to this non-configured OS. We can enter priviliged mode with no password.
Router>
enable
Router#
show version
Cisco IOS Software [Everest], ISR Software (X86_64_LINUX_IOSD-UNIVERSALK9-M), Version 16.6.4,RELEASE SOFTWARE (fc3)
[cut]
Configuration register is 0x2142
this verifies that our configs are not in use (no hostname in the prompt) and our config register has been changed to 2142
HERE IS THE KEY-
we are going to restore the configuration by copying the "startup-config"
into our live environment AKA the "running-config"
Router#
copy startup-config running-config
Destination filename [running-config]? Enter
695 bytes copied in 0.416 secs (1670 bytes/sec)
4331#
%SYS-5-CONFIG_I: Configured from console by console
we get our old prompt back:
4331#
Note that we DO NOT know the password required to enter privliged mode that we are currently inside of!
if you exit this prompt back out to user mode, you will not be able to get back in without the password.
We entered privileged mode from within the generic configuration. Then inserted our saved configuration 'beneath' our prompt.
This action does not kick you out of priv. mode, which will allow us to RESET the password for our saved configuration.
set the new password
4331(config)#
enable secret 0000
set the config register back to default, to point back to NVRAM on the next reboot
(you can do this from global config mode as well as rommon mode)
4331(config)#
config-register 0x2102
4331#
show version
[cut]
Configuration register is 0x2142 (will be 0x2102 at next reload)
now we can save the config with the updated password.
Two ways to do it-
4331#
write
Building configuration...
[OK]
OR
4331#
copy running-config startup-config
Destination filename [startup-config]?
Building configuration...
[OK]
reload the router and your new password will be saved into your config
4331#
reload
this feature is helpful since Cisco equipment tends to run for long stretches of time (years) and the passwords get forgotten.
Thank you to Jeremy Cioara for help on this topic
5. Back up an IOS image
we can copy a router's configuration to a TFTP server with either of these commands:
Router#
copy running-config tftp
Router#
copy startup-config tftp
to verify either of the configs before backup, we can use these commands:
Router#
show running-config
Router#
show startup-config
6. Restore or upgrade an IOS image - note we are talking about the IOS itself, not the 'configuration'
We will download the IOS file from TFTP server to flash memory on the router. Command requires the IP of the TFTP host and the filename
Before we begin we must make sure the IOS file is in the default TFTP directory on the host.
The command will not ask you where the file is on the host....
Router#
copy tftp flash
Address or name of remote host []? 1.1.1.2
Source filename []? c2800nm-advsecurityk9-mz.124.12.bin
Destination filename[c2800nm-advsecurityk9-mz.124.12.bin]? ENTER
%Warning this is a file already existing with this name
Do you want to over write [confirm] ENTER
Accessing tftp://1.1.1.2/c2800nm-advsecurityk9-mz.124-12.bin...
Loading c2800nm-advsecurityk9-mz.124-12.bin from 1.1.1.2 (via FastEthernet0/0): !!!!!!!!!!!!!!!!
!!!!!!!!!!!!!!!!!!!!!!!!!!
[OK - 21710744 bytes]
21710744 bytes copied in 82.880 secs (261954 bytes/sec)
Router#
to restore configuration:
restore from startup-config:
Router#
copy startup-config running-config
or we can restore from a backup on TFTP server
Router#
copy tftp running-config
Address or name of remote host []? 1.1.1.2
Source filename []? todd-confg
Destination filename[running-config?] ENTER
Accessing tftp://1.1.1.2/todd-confg...
Loading todd-confg from 1.1.12 (civa FastEthernet0/0): !
[OK - 776 bytes]
776 bytes copied in 9.212 secs (84 bytes/sec)
Router#
*Jan 23 12:40:00.000: %SYS-5-CONFIG_I: Configured from tftp://1.1.1.2/todd-confg by console
Router#
7. Describe best practices to prepare to back up an IOS image to a network server
Ensure you can acccess the network server, and there is adequate storage space.
Verify the file naming and path requirements
have the source IOS file in the default TFTP directory
8. Save the configuration of a router
Router#
copy running-config startup-config
9. Erase the configuration of a router
Router#
erase startup-config
10. Understand and use the Cisco IFS file system management commands
IFS = IOS File System
UNIX Based
dir
show files in a directory. Requires privliged mode. If not path is given as argument, you'll see the directory of 'flash' root.
NOTE the file paths use a URL format
R1#
dir
Directory of flash:/
3 -rw- 486899872 <no date> isr4300-universalk9.16.06.04.SPA.bin
2 -rw- 28282 <no date> sigdef-category.xml
1 -rw- 227537 <no date> sigdef-default.xml
3249049600 bytes total (2761893909 bytes free)
-------------------------------------------------------------------------------------------------------
copy
often used to backup, restore, or ugprade the IOS
first arg = source
second arg = destination
R1#
copy
source
destination
-------------------------------------------------------------------------------------------------------
more
display a text file
-------------------------------------------------------------------------------------------------------
show file
display a text file
-------------------------------------------------------------------------------------------------------
delete
remote file (may also need to use SQUEEZE to free up the space)
-------------------------------------------------------------------------------------------------------
erase/format
may delete flash drive depending on system
-------------------------------------------------------------------------------------------------------
cd/pwd
change directory / print working directory
-------------------------------------------------------------------------------------------------------
mkdir/rmdir
create / delete directories
11. Describe the value of CDP
Cisco Discovery Protocol - helps to document / troubleshoot the network
See lab 7.4
12. List the information provided by the output of
show cdp neighbors
device ID
local interface
holdtime
capabilility
platform
port ID (remote interface)
13. Understand how to establish a Telnet session with multiple routers simultaneously
Press Ctrl+Shift+6 then x to exit a telnet session without closing it
14. Identify current Telnet sessions
R1#
show sessions
15. Build a static host table on a router
R1#
ip host
host_name
ip_address
manually assigning an IP to a host name. You can apply multiple IP's to one host entry
see lab 7.6
16. Verify the host table on a router
R1#
show hosts
17. Describe the function of the ping command
Packet Internet Groper uses ICMP echo requests and replies to verify an active IP address on a network
18. Ping a vaild host ID from the correct prompt
R1#
ping 1.1.1.1
Note PING works from user or privliged mode but NOT config mode
Chapter 7 Written Lab 7.1 - IOS Management
TFTP Server Setup - network layout is not from book- I created this network to help demo the written lab
TFTP server is already created and switched on by default within the 'Server' object
Router Configuration
R1(config)#
int g0/0/1
R1(config-if)#
ip address 10.1.1.4 255.255.255.0
R1(config-if)#
no shutdown
%LINK-5-CHANGED: Interface GigabitEthernet0/0/1, changed state to up
%LINEPROTO-5-UPDOWN: Line protocol on Interface GigabitEthernet0/0/1, changed state to up
r1(config-if)#
do show ip int brief
Interface IP-Address OK? Method Status Protocol
GigabitEthernet0/0/0 unassigned YES manual administratively down down
GigabitEthernet0/0/1 192.1.1.4 YES NVRAM up up
GigabitEthernet0/0/2 unassigned YES NVRAM administratively down down
Vlan1 unassigned YES NVRAM administratively down down
Switch Configuration
SW1(config)#
int f0/1
SW1(config-if)#
no shutdown
%LINK-5-CHANGED: Interface FastEthernet0/1, changed state to up
%LINEPROTO-5-UPDOWN: Line protocol on Interface FastEthernet0/1, changed state to up
SW1(config-if)#
int f0/2
SW1(config-if)#
no shutdown
%LINK-5-CHANGED: Interface FastEthernet0/2, changed state to up
%LINEPROTO-5-UPDOWN: Line protocol on Interface FastEthernet0/2, changed state to up
Test connectivity to the server
R1#
ping 192.1.1.3
Type escape sequence to abort.
Sending 5, 100-byte ICMP Echos to 192.1.1.3, timeout is 2 seconds:
.!!!!
Success rate is 80 percent (4/5), round-trip min/avg/max = 0/1/6 ms
Find the name of the Router flash file
R1#
show flash
System flash directory:
File Length Name/status
3 486899872isr4300-universalk9.16.06.04.SPA.bin
2 28282 sigdef-category.xml
1 227537 sigdef-default.xml
[487155691 bytes used, 2761893909 available, 3249049600 total]
3.17338e+06K bytes of processor board System flash (Read/Write)
we need to paste that filename into our copy command below
1. command to copy a Cisco IOS to a TFTP server?
R1#
copy flash tftp
Source filename []? isr4300-universalk9.16.06.04.SPA.bin
Address or name of remote host []? 192.1.1.3
Destination filename [isr4300-universalk9.16.06.04.SPA.bin]? ENTER
Writing isr4300-universalk9.16.06.04.SPA.bin...!!!!!!!!!!!!!!!!
!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!
[OK - 486899872 bytes]
486899872 bytes copied in 12.364 secs (126865 bytes/sec)
the file appears on our server
2. command to copy a Cisco startup-config file to a TFTP server?
R1#
copy running-config tftp
Address or name of remote host []? 192.1.1.3
Destination filename [r1-confg]? ENTER
Writing running-config.....!!
[OK - 707 bytes]
707 bytes copied in 3 secs (235 bytes/sec)
the file appears on our server
OR
R1#
copy startup-config tftp
3. command to copy the startup-config file to DRAM?
R1#
copy startup-config running-config
the running configuration exists in DRAM
4. What is an older command that you can use to copy the startup-config file to DRAM?
R1#
config mem
(not supported by packet tracer)
5. What command can you use to see the neighbor router's IP address from your router prompt?
R1#
show cdp neighbor detail
OR
R1#
show cdp entry *
6. What command to see the hostname, local interface, platform, and remote port of a neighbor router?
R1#
show cdp neighbor
7. What keystrokes can you use to telnet into multiple devices simultaneously?
Ctrl + Shift + 6, then X
8. What command will show you your active Telnet connections to neighbor and remote devices?
R1#
show sessions
9. What command can you use to upgrade a Cisco IOS?
R1#
copy tftp flash
10. What command can you use to merge a backup configuration with the configuration in RAM?
R1#
copy tftp run
OR
R1#
copy start run
RAM = running configuration
Chapter 7 Written Lab 7.2 - Router Memory
Identify the location in a router where each of the files is stored by default:
1. Cisco IOS
flash
2. Bootstrap
ROM
3. Startup configuration
NVRAM
4. POST
ROM
5. Running configuration
RAM
6. ARP cache
RAM
7. Mini IOS
ROM
8. ROM Monitor
ROM
9. Routing tables
RAM
10. packet buffers
RAM
****dont make the mistake of thinking arp cache, routing tables, packet buffers, are stored somewhere other than RAM
they are considered part of running-config which exists in RAM
Chapter 7 Hands-on Labs
To complete these labs, we are going to need three routers and one TFTP server.
Here is the topology:
Server Configuration
ipv4 address: 193.1.1.2
subnet mask: 255.255.255.248
default gateway: 193.1.1.1
Switch Configuration
SW1#
interface range f0/1-2
SW1(config-if-range)#
no shut
Router Configurations
R1(config)#
int g0/0/0
R1(config)#
ip addr 193.1.1.9 255.255.255.248
R1(config)#
no shut
R1(config)#
int g0/0/1
R1(config)#
ip addr 193.1.1.1 255.255.255.248
R1(config)#
no shut
the server's default gateway
R2(config)#
int g0/0/0
R2(config)#
ip addr 193.1.1.10 255.255.255.248
R2(config)#
no shut
R2(config)#
int g0/0/1
R2(config)#
ip addr 193.1.1.17 255.255.255.248
R2(config)#
no shut
R3(config)#
int g0/0/0
R3(config)#
ip addr 193.1.1.18 255.255.255.248
R3(config)#
no shut
the segment between R1 and the server
network 193.1.1.0/29
block of 8
hosts .1, .2
the segment between R1 and R2
network 193.1.1.8/29
block of 8
hosts .9 , .10
the segment between the R2 and R3
network 193.1.1.16/29
block of 8
hosts .17 , .18
THIS IS INCORRECT!!!!
I have misunderstood the instructions.
the problem with this topology is that packets cannot pass through the routers. We dont have any ROUTING setup. ROUTING is covered in the next chapter.
For these labs, we dont need routing, but we need multiple routers to demo telnet and CDP. Here are the instructions:
my mistake was not putting all router interfaces in the same subnet. I tried to do this initially, but it wouldnt work because I had the routers linked together rather than connected by a switch.
The instructions say:
"Your PC and the router(s) are connected together with a switch"
this is the part I missed. The pc and all router interfaces should be on the same switch and the same network
Here is the corrected topology
Server Configuration
ipv4 address: 193.1.1.4
subnet mask: 255.255.255.248
default gateway: 193.1.1.1
Switch Configuration
SW1#
interface range f0/1-4
SW1(config-if-range)#
no shut
Router Configurations
R1(config)#
int g0/0/0
R1(config)#
ip addr 193.1.1.1 255.255.255.248
R1(config)#
no shut
the server's default gateway
R2(config)#
int g0/0/0
R2(config)#
ip addr 193.1.1.2 255.255.255.248
R2(config)#
no shut
R3(config)#
int g0/0/0
R3(config)#
ip addr 193.1.1.3 255.255.255.248
R3(config)#
no shut
Chapter 7 Hands-on Lab 7.1 Backing up your router IOS
1. verify connection to the server
R1#
ping 193.1.1.1
Type escape sequence to abort.
Sending 5, 100-byte ICMP Echos to 193.1.1.2, timeout is 2 seconds:
.!!!!
Success rate is 80 percent (4/5), round-trip min/avg/max = 0/1/5 ms
2. show contents of flash memory
R1#
show flash
System flash directory:
File Length Name/status
3 486899872isr4300-universalk9.16.06.04.SPA.bin
2 28282 sigdef-category.xml
1 227537 sigdef-default.xml
[487155691 bytes used, 2761893909 available, 3249049600 total]
3.17338e+06K bytes of processor board System flash (Read/Write)
show flash gives ALL of the files in flash memory
show version gives the current running file
3. show the IOS currently running
R1#
show version
Cisco IOS XE Software, Version 03.16.05.S - Extended Support Release
[cut]
ROM: IOS-XE ROMMON
Router uptime is 9 minutes, 39 seconds
Uptime for this control processor is 9 minutes, 39 seconds
System returned to ROM by power-on
System image file is "bootflash:/isr4300-universalk9.03.16.05.S.155-3.S5-ext.SPA.bin"
Last reload reason: PowerOn
[cut]
note that the file that is currently running is NOT located in the flash storage!!!
4. backup IOS from router to server
R1#
copy flash tftp
Source filename []?isr4300-universalk9.16.06.04.SPA.bin
Address or name of remote host []? 193.1.1.4
Destination filename [isr4300-universalk9.16.06.04.SPA.bin]? ENTER
Writing isr4300-universalk9.16.06.04.SPA.bin...!!!!!!!!!!!!!!!
[OK - 486899872 bytes]
486899872 bytes copied in 12.526 secs (125224 bytes/sec)
Chapter 7 Hands-on Lab 7.2 Upgrading or restoring your router IOS
1. verify connection to the server
R1#
ping 193.1.1.4
Type escape sequence to abort.
Sending 5, 100-byte ICMP Echos to 193.1.1.2, timeout is 2 seconds:
!!!!!
Success rate is 100 percent (5/5), round-trip min/avg/max = 0/0/1 ms
2. copy from tftp sever to flash
R1#
copy tftp flash TFTP comes first in the command since we are pulling from TFTP server.
In this command, remot host address is required before file name
Address or name of remote host []? 193.1.1.4
Source filename []?isr4300-universalk9.16.06.04.SPA.bin
Destination filename [isr4300-universalk9.16.06.04.SPA.bin]? ENTER
%Warning:There is a file already existing with this name
Do you want to over write? [confirm]
Accessing tftp://193.1.1.4/isr4300-universalk9.16.06.04.SPA-12-23-22...
Loading isr4300-universalk9.16.06.04.SPA-12-23-22.bin from 193.1.1.4: !!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!
[OK - 486899872 bytes]
486899872 bytes copied in 12.785 secs (122688 bytes/sec)
Chapter 7 Hands-on Lab 7.3 Backing up the router configuration
1. verify connection to the server
R1#
ping 193.1.1.2
Type escape sequence to abort.
Sending 5, 100-byte ICMP Echos to 193.1.1.4, timeout is 2 seconds:
!!!!!
Success rate is 100 percent (5/5), round-trip min/avg/max = 0/0/1 ms
2. copy running-confing to server
R1#
copy run tftp
Address or name of remote host []? 193.1.1.4
Destination filename [R1-confg]?ENTER "R1-confg" is the default name
Writing running-config...!!
[OK - 668 bytes]
668 bytes copied in 0.004 secs (167000 bytes/sec)
Chapter 7 Hands-on Lab 7.4 Using the Cisco Discovery Protocol (CDP)
R1#
show cdp
Global CDP information:
Sending CDP packets every 60 seconds
Sending a holdtime value of 180 seconds
Sending CDPv2 advertisements is enabled
R1#
show cdp interface
Vlan1 is administratively down, line protocol is down
Sending CDP packets every 60 seconds
Holdtime is 180 seconds
GigabitEthernet0/0/0 is up, line protocol is up
Sending CDP packets every 60 seconds
Holdtime is 180 seconds
GigabitEthernet0/0/1 is administratively down, line protocol is down
Sending CDP packets every 60 seconds
Holdtime is 180 seconds
GigabitEthernet0/0/2 is administratively down, line protocol is down
Sending CDP packets every 60 seconds
Holdtime is 180 seconds
R1#
show cdp entry *
Device ID: SW1
Entry address(es):
Platform: cisco 2960, Capabilities: Switch
Interface: GigabitEthernet0/0/0, Port ID (outgoing port): FastEthernet0/1
NOTE g0/0/0 is the outgoing port on this router, F0/1 is the port on the switch at other end
Holdtime: 157
Version :
Cisco IOS Software, C2960 Software (C2960-LANBASEK9-M), Version 15.0(2)SE4, RELEASE SOFTWARE (fc1)
Technical Support: http://www.cisco.com/techsupport
Copyright (c) 1986-2013 by Cisco Systems, Inc.
Compiled Wed 26-Jun-13 02:49 by mnguyen
advertisement version: 2
Duplex: full
R1#
show cdp entry neighbors
[no output]
R1#
show cdp neighbors detail
Device ID: SW1
Entry address(es):
Platform: cisco 2960, Capabilities: Switch
Interface: GigabitEthernet0/0/0, Port ID (outgoing port): FastEthernet0/1
Holdtime: 178
Version :
Cisco IOS Software, C2960 Software (C2960-LANBASEK9-M), Version 15.0(2)SE4, RELEASE SOFTWARE (fc1)
Technical Support: http://www.cisco.com/techsupport
Copyright (c) 1986-2013 by Cisco Systems, Inc.
Compiled Wed 26-Jun-13 02:49 by mnguyen
advertisement version: 2
Duplex: full
Chapter 7 Hands-on Lab 7.5 Using Telnet
enable telnet on R2 and set password
R2(config)#
line vty 0 15
R2(config-line)#
password telnet
R2(config-line)#
login
enable telnet on R3 and set password
R3(config)#
line vty 0 15
R3(config-line)#
password telnet
R3(config-line)#
login
note that the result of this command on each router, by default,
is to present all 15 lines in TWO SEPERATE chunks: 0-4 and 5-15
R3#
show run
[cut]
!
!
!
line con 0
!
line aux 0
!
line vty 0 4
password telnet
login
line vty 5 15
password telnet
login
!
!
!
end
--------------------------------------------------------------------------------
connect to R2 from R1
R1#
telnet 193.1.1.2
Trying 193.1.1..2 ...Open
User Access Verification
Password: telnet
prompt changes to R2 to indicate we are remoted in
R2>
exit the session
ctrl + shift + 6, x
prompt changes back to R1
R1#
--------------------------------------------------------------------------------
connect to R3 from R1
R1#
193.1.1.3 note that the word 'telnet' is not required bc we are still in telnet mode
Trying 193.1.1..3 ...Open
User Access Verification
Password: telnet
prompt changes to R3 to indicate we are remoted in
R3>
exit the session
ctrl + shift + 6, x
prompt changes back to R1
R1#
--------------------------------------------------------------------------------
We have exited the sessions, but they are still open
R1#
show sessions
Conn Host Address Byte Idle Conn Name
1 193.1.1.2 193.1.1.2 0 0 193.1.1.2
* 2 193.1.1.3 193.1.1.3 0 0 193.1.1.3
two telnet sessions- notice that the 'conn number' doesnt correspond to ip address in any way.
R1#
show users
Line User Host(s) Idle Location
* 0 con 0 193.1.1.2 00:00:03
193.1.1.3 00:00:43
this is saying one user is on this router, with two outbound connections (but it isnt showing that they are vty connections)
... they must both be considered 'console' connections outbound and are not considered 'vty' until they are received inbound
the asterisk means something different here than above... doesnt mean default(most recent)session... what does it mean?
back to R2
R2#
show users
Line User Host(s) Idle Location
* 4 vty 0 idle 00:00:00 193.1.1.1
Interface User Mode Idle Peer Address
this is saying that there is one (unnamed) user remoted in via line vty 4
back to R3
R3#
show users
Line User Host(s) Idle Location
* 4 vty 0 idle 00:00:00 193.1.1.1
Interface User Mode Idle Peer Address
this is saying that there is one (unnamed) user remoted in via line vty 4
-------------------------------------------------------------------------------------
Important Considerations:
-
asterisk indicates default session
-
when telnetting in, you will be in user mode. If there is no password already set for PRIVILEGED MODE, you will be unable to enter
-
be careful with 'exit'. it will exit the telnet session if you exit at priv. mode. Use 'disable' to leave priv mode.
-
after 'suspending' a session with ctrl+shift+6,x and youre back at your original priv. prompt, do not press enter to create line breaks-
rather than break lines as usual, the keystroke will cause this:
[Resuming connection 1 to 193.1.1.2 ... ]
prompt will sit here until you strike enter again, then you'll return to that session. What is actually happening is that
youre connecting to the 'default' telnet connection. The same behavior happens when youre at the 'show sessions' screen.
Even if you are not viewing active sessions, the enter key(twice) will connect you to the default session
-
you can use disconnect or exit to end a session
-
Ex: disconnect 1 at the show sessions screen
Chapter 7 Hands-on Lab 7.6 Resolving Hostnames
We're going to build a host table on R1 so we can connect to the other routers via hostname rather than type in the IP address
the command is ip host name arg ip arg
R1(config)#
ip host R2 193.1.1.2
R1(config)#
ip host R3 193.1.1.3
Now if we enter R2 or telnet R2 we get the telnet prompt
R1# R2
Trying 193.1.1.2 ...Open
User Access Verification
Password:
same for the PING command
R1# ping R2
Type escape sequence to abort.
Sending 5, 100-byte ICMP Echos to 193.1.1.2, timeout is 2 seconds:
!!!!!
Success rate is 100 percent (5/5), round-trip min/avg/max = 0/0/2 ms
R1#
show hosts
Default Domain is not set
Name/address lookup uses domain service
Name servers are 255.255.255.255
Codes: UN - unknown, EX - expired, OK - OK, ?? - revalidate
temp - temporary, perm - permanent
NA - Not Applicable None - Not defined
Host Port Flags Age Type Address(es)
R2 None (perm, OK) 0 IP 193.1.1.2
R3 None (perm, OK) 0 IP 193.1.1.3
R1#
telnet R2
R2>
CTRL + SHIFT + 6, X
R1#
telnet R3
R3>
CTRL + SHIFT + 6, X
R1#
show session
Conn Host Address Byte Idle Conn Name
1 R2 193.1.1.2 0 0 R2
* 2 R3 193.1.1.3 0 0 R3
Chapter 7 Review Questions
1. What does the command
confreg 0x2142
provide?
bypass startup-config, to allow password reset
2. Which command will copy the IOS to a backup host on your network?
copy flash tftp
3. You are troubleshooting a connectivity problem in your corporate network and want to isolate the problem. You suspect that a router on the route to an unreachable
network is at fault. What IOS user exec command should you issue?
traceroute
note this is not a priviliged mode command; it can be run from user mode
4. You copy a configuration from a network host to a router's RAM. The configuration looks correct, yet it is no working at all. What could the problem be?
when you perform a copy from a network host to a router, the interfaces are automatically shut down and have to be manually enabled with no shutdown
5. A network administrator wants to upgrade the IOS of a router without removing the image currently installed. What command will display the amount of memory consumed by the
current IOS image and indicate whether there is enough room available to hold both the current and new images?
show flash
6. The corporate office sends you a new router to connect, but upon connecting the console cable, you see that there is already a configuration on the router.
What should be done before a new configuration is entered in the router?
erase NVRAM and restart the router
erase startup-config
reload
7. Which command loads a new version of the Cisco IOS into a router?
copy tftp flash
8. Which command will show you the IOS version running on your router?
show version
9. What should the configuration register value be after you successfully complete the password recovery procedure and return the router to normal operation?
0x2102
10. You save the configuration on a router with the
copy running-config startup-config
command and reboot the router. The router, however, comes up with a blank configuration. What can the problem be?
wrong config register causing you to bypass startup-confing in NVRAM
11. If you want to have more than one Telnet session open at the same time, what keystroke combination would you use?
CTRL+SHIFT+6, X
12. You are unsuccessful in telnetting into a remote device, but you could telnet to the router earlier, However, you can still ping the remote device.
What can the problem be?
access control list could be filtering telnet
OR
the VTY password may not be set on the target
13. What information is displayed by the
show hosts
command?
gives info on temporary DNS entries and permanent name-to-address mappings created using the ip host command
14. Name three commands that can be used to check LAN connectivity problems on a router?
trace
show interfaces
show ip route
15. You telnet to a router and make your necessary changes; now you want to end the Telnet session. What command do you type in?
exit
16. You telnet into a remote device and type
debug ip rip
but no output from the
debug
command is seen. What could the problem be?
to see console messages through a telnet session, you must enter the command terminal monitor
17. Which command displays the configuration register setting?
show version
18. You need to gather the IP address of a remote switch that is located in Hawaii. What can you do to find the address?
show cdp neighbors detail
19. You have your laptop directly connected into a router's Ethernet port. Which are requirements for the
copy flash tftp
command to be successful?
have a TFTP server running on the laptop
laptop must have an IP on the same subnet as the router interface
give the IP address of the laptop when asked after entering the command
20. The configuration register setting of 0x2102 provides what function to a router?
points to NVRAM for startup-configuration AND boot sequence
END CHAPTER 7
26 hours 1-19 thru 1-26-22
original total hours 89
7 hours review 12-23-22
review total hours 20.5
book page 344/822
avg 15 min/page (reading and exercises/labs)
Chapter 8 Exercises
pg 374
before I begin to configure this network, I want to look closer at the HARDWARE
Todd mentions these routers:
2811 with four serial interfaces and switch module or wireless card
1841
while the book was published in 2011, both routers appear to be available in 2021 packet tracer,
but both are considered legacy as of Feb 2022.
The 2811:
The 1841:
we're going to need to understand the MODULES. What are these?
a few examples:
NM-1E is a 1-port ethernet module
NM-1FE-TX is a fast ethernet module
NM-8A/s is an Eight Port Async/Sync Network Module
HWIC-2T is a 2-port serial WAN interface card
HWIC-AP-AG-B is a wireless card
What is an "NM module"?
A network module is a software module that implements a specific
function in a network stack, such as a data link interface, a transport protocol,
or a network application.
What is a "HWIC module"?
A high-speed WAN interface card
Here is a look inside a real 2811:
Back to the requirements for our lab- Todd says the 2811 'Corp' router needs a switch module
and four serial interfaces. NOTE the book doesnt give specifics on how to create the topology in Packet Tracer.
Our Packet Tracer 2811 offers these modules:
The NM-ESW-16 appears to be the only 'switch module', so I will add that.
And the HWIC-2T is a 2-Port Serial High-Speed WAN Interface Card, providing 2 serial ports.
I will add two of these.
next: R3, which needs to be a 2811 with a wirless card. I will add the HWIC-AP-AG-B:
The HWIC-AP-AG-B module is a High-Speed WAN Interface Card providing integrated Access Point
functionality in the Cisco 1800 (Modular), Cisco 2800,
and Cisco 3800 Integrated Services Routers.
It supports Single Band 802.11b/g or Dual Band 802.11a/b/g radios.
our router hardware is in place:
and here is where we need to end up
Next we need to figure out how to connect the server farm to the switch card on R1:
if I use the auto-select cable, I get a copper crossover cable connecting at fa0/0 on the router.
Per the diagram fa0/0 should
connect to R3. I need to connect the servers to the switch card on R1.
Instead of using the auto-select cable, I'll try a straight-through cable.
Success. While the auto-select cable did not give me an option as to what port it will connect to, I did get the option when
manually applying the straight-through cable. Instead of connecting to F0/0 which would require a crossover-cable(computer to router),
I will connect to the integrated switch at port F1/0, then connect the other two servers to F1/1 and F1/2, respectively.
Also worth noting: the Physical Device diagrams in Packet Tracer do not show cables plugged into the ports.
We are relying on the labels on the logical diagram to see which cables are plugged into which ports...
As far as how we can tell what is connected from within the CLI.. I dont know right now.
Now I will connect the other routers. Here is the chart specifiying what interfaces should be used:
Router
Network Address
Interface
Address
CORP
10.1.1.0
Vlan1 (switch card)
10.1.1.1
10.1.2.0
S0/0/0
10.1.2.1
10.1.3.0
S0/0/1 (DCE)
10.1.3.1
10.1.4.0
S0/1/0
10.1.4.1
10.1.5.0
F0/0
10.1.5.1
R1
10.1.2.0
S0/0/0 (DCE)
10.1.2.2
10.1.3.0
S0/0/1
10.1.3.2
192.168.10.0
F0/0
192.168.10.1
192.168.20.0
F0/1
192.168.20.1
R2
10.1.4.0
S0/0/0 (DCE)
10.1.4.2
192.168.30.0
F0/0
192.168.30.1
192.168.40.0
F0/0
192.168.40.1
R3
10.1.5.0
F0/0
10.1.5.2
172.16.10.0
Dot11Radio0/0/0
172.16.10.1
PROBLEM
The R1 router doesnt appear to have any serial interfaces
I will add an HWIC-2T card to both R1 and R2 since the diagram calls for serial interfaces.
The HWIC-2T is a Cisco 2-Port Serial High-Speed WAN Interface Card, providing 2 serial ports.
PROBLEM
The Corp router is not showing the expected available interfaces. I need to connect R1 to the S0/0/0 interface on Corp and R2 to the S0/0/1 interface on Corp.
My Corp router is not showing those interfaces:
Solution
the placement of the cards on the router determines which interface numbers will be available.
In this case, it seems the interfaces start from the bottom right corner and increase on each slot moving clockwise. I found this out by filling all four slots on my router
which led to all interfaces being available. I then ran a card in each slot individually to isolate which interface numbers correspond to each slot:
Interestingly, while the physical slots seem to follow a 'clockwise' pattern, the list of available slots in the logical diagram does not;
We get an output of interfaces corresponding to slot 2, then 3, 1, and 4. This is a 'bottom to top' then 'left to right' pattern. Tricky.
Having said all that... I will run cards in slots 1 and 2 for this lab since we only need interfaces S0/0/0, S0/0/1, S0/1/0
The Router topology:
I'm not clear on the connections from R1 and R2 to the clients.. I assume there are switches involved.
For now I will follow the next steps in the book which
are to configure the corp router as follows:
Router(config)#
hostname Corp
Corp(config)#
enable secret todd
Corp(config)#
interface vlan 1
Corp(config-if)#
description Switch Card to Core Network
Corp(config-if)#
ip address 10.1.1.1 255.255.255.0
Corp(config-if)#
no shut
----------------------------------------------------------------------------------------------------------------
Corp(config-if)#
int f1/0
Corp(config-if)#
description Switch Port connection to WWW Server
Corp(config-if)#
no shutdown
Corp(config-if)#
int f1/1
Corp(config-if)#
description Switch Port connection to Email Server
Corp(config-if)#
no shutdown
Corp(config-if)#
int f1/2
Corp(config-if)#
description Switch Port connection to DNS Server
Corp(config-if)#
no shutdown
----------------------------------------------------------------------------------------------------------------
Corp(config-if)#
int s0/0/0
Corp(config-if)#
description 1st Connection to R1
Corp(config-if)#
ip address 10.1.2.1 255.255.255.0
Corp(config-if)#
no shut
Corp(config-if)#
int s0/0/1
Corp(config-if)#
description 2nd Connection to R1
Corp(config-if)#
ip address 10.1.3.1 255.255.255.0
Corp(config-if)#
no shut
Corp(config-if)#
int s0/1/0
Corp(config-if)#
description Connection to R2
Corp(config-if)#
ip address 10.1.4.1 255.255.255.0
Corp(config-if)#
no shut
Corp(config-if)#
int fa0/0
Corp(config-if)#
description Connection to R3
Corp(config-if)#
ip address 10.1.5.1 255.255.255.0
Corp(config-if)#
no shut
----------------------------------------------------------------------------------------------------------------
Corp(config-if)#
line con 0
Corp(config-if)#
password console
Corp(config-if)#
login
Corp(config-if)#
logging synchro
Corp(config-if)#
exec-timeout 0 0
----------------------------------------------------------------------------------------------------------------
Corp(config-if)#
line aux 0
Corp(config-if)#
password aux
Corp(config-if)#
login
Corp(config-if)#
exit
----------------------------------------------------------------------------------------------------------------
Corp(config)#
line vty ?
<1-15>Last Line number
Corp(config)#
line vty 0 15
Corp(config-if)#
password telnet
Corp(config-if)#
login
Corp(config-if)#
exit
----------------------------------------------------------------------------------------------------------------
Corp(config)#
no ip domain lookup
Corp(config)#
banner motd # This is my Corp 2811 ISR Router #
Ctrl + Z
%SYS-5-CONFIG_I: Configured from console by console
(Ctrl-Z: When in a config mode, ends the config mode and returns you to privileged EXEC mode.... same as typing exit(?))
Corp#
copy run start
Destination filename [startup-config]?
Building configuration...
[OK]
----------------------------------------------------------------------------------------------------------------
Corp#
show ip int br
Interface IP-Address OK? Method Status Protocol
FastEthernet0/0 10.1.5.1 YES manual up down
FastEthernet0/1 unassigned YES unset administratively down down
Serial0/0/0 10.1.2.1 YES manual down down
Serial0/0/1 10.1.3.1 YES manual down down
Serial0/1/0 10.1.4.1 YES manual down down
Serial0/1/1 unassigned YES unset administratively down down
FastEthernet1/0 unassigned YES unset up up
FastEthernet1/1 unassigned YES unset up up
FastEthernet1/2 unassigned YES unset up up
FastEthernet1/3 unassigned YES unset administratively down down
FastEthernet1/4 unassigned YES unset administratively down down
FastEthernet1/5 unassigned YES unset administratively down down
FastEthernet1/6 unassigned YES unset administratively down down
FastEthernet1/7 unassigned YES unset administratively down down
FastEthernet1/8 unassigned YES unset administratively down down
FastEthernet1/9 unassigned YES unset administratively down down
FastEthernet1/10 unassigned YES unset administratively down down
FastEthernet1/11 unassigned YES unset administratively down down
FastEthernet1/12 unassigned YES unset administratively down down
FastEthernet1/13 unassigned YES unset administratively down down
FastEthernet1/14 unassigned YES unset administratively down down
FastEthernet1/15 unassigned YES unset administratively down down
Vlan1 10.1.1.1 YES manual up up
----------------------------------------------------------------------------------------------------------------
Corp#
show run
Building configuration...
Current configuration : 2073 bytes
!
version 15.1
no service timestamps log datetime msec
no service timestamps debug datetime msec
no service password-encryption
!
hostname Corp
!
!
!
enable secret 5 $1$mERr$V5ujdIM9bTB/I.ipB0gkJ0
!
!
!
!
!
!
no ip cef
no ipv6 cef
!
!
!
!
license udi pid CISCO2811/K9 sn FTX1017U440-
!
!
!
!
!
!
!
!
!
no ip domain-lookup
!
!
spanning-tree mode pvst
!
!
!
!
!
!
interface FastEthernet0/0
description connection to R3
ip address 10.1.5.1 255.255.255.0
duplex auto
speed auto
!
interface FastEthernet0/1
no ip address
duplex auto
speed auto
shutdown
!
interface Serial0/0/0
description 1st connection to R1
ip address 10.1.2.1 255.255.255.0
clock rate 2000000
!
interface Serial0/0/1
description 2nd connection to R1
ip address 10.1.3.1 255.255.255.0
clock rate 2000000
!
interface Serial0/1/0
description connection to R2
ip address 10.1.4.1 255.255.255.0
!
interface Serial0/1/1
no ip address
clock rate 2000000
shutdown
!
interface FastEthernet1/0
description switch port connection to WWW Server
!
interface FastEthernet1/1
description switch port connection to Email Server
!
interface FastEthernet1/2
description switch port connection to DNS Server
!
interface FastEthernet1/3
shutdown
!
interface FastEthernet1/4
shutdown
!
interface FastEthernet1/5
shutdown
!
interface FastEthernet1/6
shutdown
!
interface FastEthernet1/7
shutdown
!
interface FastEthernet1/8
shutdown
!
interface FastEthernet1/9
shutdown
!
interface FastEthernet1/10
shutdown
!
interface FastEthernet1/11
shutdown
!
interface FastEthernet1/12
shutdown
!
interface FastEthernet1/13
shutdown
!
interface FastEthernet1/14
shutdown
!
interface FastEthernet1/15
shutdown
!
interface Vlan1
description Switch Card to Core Network
ip address 10.1.1.1 255.255.255.0
!
ip classless
!
ip flow-export version 9
!
!
!
banner motd ^C This is my Corp 2811 ISR Router ^C
!
!
!
!
!
line con 0
exec-timeout 0 0
password console
logging synchronous
login
!
line aux 0
password aux
login
!
line vty 0 4
password telnet
login
line vty 5 15
password telnet
login
!
!
!
end
-----------------------------------------------------------------------------------------------------------------------
more configurations:
R1
Router(config)#
hostname R1
R1(config)#
enable secret todd
R1(config)#
int s0/0/0
R1(config-if)#
ip address 10.1.2.2 255.255.255.0
R1(config-if)#
Decription 1st connection to corp router
R1(config-if)#
no shut
-----------------------------------------------------------------------------------------------
R1(config-if)#
int s0/0/1
R1(config-if)#
ip address 10.1.3.2 255.255.255.0
R1(config-if)#
Decription 2nd connection to corp router
R1(config-if)#
no shut
-----------------------------------------------------------------------------------------------
R1(config-if)#
int f0/0
R1(config-if)#
ip address 192.168.10.1 255.255.255.0
R1(config-if)#
Decription connection to finance
R1(config-if)#
no shut
-----------------------------------------------------------------------------------------------
R1(config-if)#
int f0/1
R1(config-if)#
ip address 192.168.20.1 255.255.255.0
R1(config-if)#
Decription connection to marketing
R1(config-if)#
no shut
R1(config-if)#
exit
-----------------------------------------------------------------------------------------------
R1(config)#
line con 0
R1(config-line)#
password console
R1(config-line)#
login
R1(config-line)#
logging synchronous
R1(config-line)#
exec-timeout 0 0
-----------------------------------------------------------------------------------------------
R1(config-line)#
line aux 0
R1(config-line)#
password aux
R1(config-line)#
login
R1(config-line)#
exit
-----------------------------------------------------------------------------------------------
R1(config)#
line vty 0 ?
<0-15> Last Line number
R1(config)#
line vty 0 807
R1(config-line)#
password telnet
R1(config-line)#
login
R1(config-line)#
banner motd # This is my R1 Router #
R1(config-line)#
exit
-----------------------------------------------------------------------------------------------
R1(config)#
no ip domain-lookup
R1(config)#
exit
R1#
copy run start
R2
Router(config)#
hostname R2
R2(config)#
enable secret todd
R2(config)#
int s0/0/0
R2(config-if)#
ip address 10.1.4.2 255.255.255.0
R2(config-if)#
description connection to corp router
R2(config-if)#
no shut
-----------------------------------------------------------------------------------------------
R2(config-if)#
int f0/0
R2(config-if)#
ip address 192.168.30.1 255.255.255.0
R2(config-if)#
description connection to sales PC
R2(config-if)#
no shut
-----------------------------------------------------------------------------------------------
R2(config-if)#
int f0/1
R2(config-if)#
ip address 192.168.40.1 255.255.255.0
R2(config-if)#
description connection to HR pc
R2(config-if)#
no shut
-----------------------------------------------------------------------------------------------
R2(config-if)#
line con 0
R2(config-line)#
password console
R2(config-line)#
login
R2(config-line)#
logging synchronous
R2(config-line)#
exec-timeout 0 0
-----------------------------------------------------------------------------------------------
R2(config-line)#
line aux 0
R2(config-line)#
password aux
R2(config-line)#
login
R2(config-line)#
exit
-----------------------------------------------------------------------------------------------
R2(config)#
line vty 0 ?
<0-15> Last Line number
R2(config)#
line vty 0 807
R2(config-line)#
password telnet
R2(config-line)#
login
R2(config-line)#
banner motd # This is my R1 Router #
R2(config-line)#
exit
-----------------------------------------------------------------------------------------------
R2(config)#
no ip domain-lookup
R2(config)#
exit
R2#
copy run start
R3
Router(config)#
hostname R3
R3(config)#
enable secret todd
R3(config)#
int f0/0
R3(config-if)#
ip address 10.1.5.2 255.255.255.0
R3(config-if)#
description connection to corp router
R3(config-if)#
no shut
-----------------------------------------------------------------------------------------------
R3(config-if)#
int dot11radio0/0/0
R3(config-if)#
ip address 172.16.10.1 255.255.255.0
R3(config-if)#
description WLAN for mobile user
R3(config-if)#
no shut
R3(config-if)#
ssid ADMIN
stuck here 2-5-22-- packet tracer isnt taking me into the config-if-ssid prompt
R3(config-if-ssid)#
guest-mode
R3(config-if-ssid)#
authentication open
R3(config-if-ssid)#
ingrastructure-ssid
R3(config-if-ssid)#
exit
-----------------------------------------------------------------------------------------------
R3(config-if)#
line con 0
R3(config-line)#
password console
R3(config-line)#
login
R3(config-line)#
logging synchronous
R3(config-line)#
exec-timeout 0 0
-----------------------------------------------------------------------------------------------
R3(config-line)#
line aux 0
R3(config-line)#
password aux
R3(config-line)#
login
R3(config-line)#
exit
-----------------------------------------------------------------------------------------------
R3(config)#
line vty 0 ?
<0-15> Last Line number
R3(config)#
line vty 0 807
R3(config-line)#
password telnet
R3(config-line)#
login
R3(config-line)#
banner motd # This is my R1 Router #
R3(config-line)#
exit
-----------------------------------------------------------------------------------------------
R3(config)#
no ip domain-lookup
R3(config)#
exit
R3#
copy run start
PROBLEM
i cant get into conf-if-ssid prompt
R3(config-if)#
ssid ADMIN
%LINK-5-CHANGED: Interface Dot11Radio0/0/0, changed state to administratively down
%LINEPROTO-5-UPDOWN: Line protocol on Interface Dot11Radio0/0/0, changed state to down
%LINK-5-CHANGED: Interface Dot11Radio0/0/0, changed state to up
%LINEPROTO-5-UPDOWN: Line protocol on Interface Dot11Radio0/0/0, changed state to up
R3(config-if)#
research led me to this thread, which is a dead end:
further research led me here:
R3(config)# global config mode
R3(config)#
dot11 ssid ADMIN
creates an SSID or lets you config an existing SSID
R3(config-ssid)#
guest-mode
R3(config-ssid)#
%LINK-5-CHANGED: Interface Dot11Radio0/0/0, changed state to administratively down
%LINEPROTO-5-UPDOWN: Line protocol on Interface Dot11Radio0/0/0, changed state to down
%LINK-5-CHANGED: Interface Dot11Radio0/0/0, changed state to up
%LINEPROTO-5-UPDOWN: Line protocol on Interface Dot11Radio0/0/0, changed state to up
R3(config-ssid)#
authentication open
R3(config-ssid)#
%LINK-5-CHANGED: Interface Dot11Radio0/0/0, changed state to administratively down
%LINEPROTO-5-UPDOWN: Line protocol on Interface Dot11Radio0/0/0, changed state to down
%LINK-5-CHANGED: Interface Dot11Radio0/0/0, changed state to up
%LINEPROTO-5-UPDOWN: Line protocol on Interface Dot11Radio0/0/0, changed state to up
R3(config-ssid)#
infrastructure-ssid
R3(config-ssid)#infrastructure-ssid
^
% Invalid input detected at '^' marker.
this command given by the book doesnt appear to be valid
R3(config-ssid)#
?
authentication authentication method
exit Exit from ssid sub mode
guest-mode guest ssid
no Negate a command or set it's defaults
wpa-psk Configure Wi-Fi Protected Access pre-shared key
back into the interface to see what the options are
R3(config-ssid)#
int dot110/0/0
R3(config-if)#
?
arp Set arp type (arpa, probe, snap) or timeout or log options
bandwidth Set bandwidth informational parameter
cdp CDP interface subcommands
crypto Encryption/Decryption commands
delay Specify interface throughput delay
description Interface specific description
encryption Configure dot11 encryption parameters
exit Exit from interface configuration mode
fair-queue Enable Fair Queuing on an Interface
hold-queue Set hold queue depth
ip Interface Internet Protocol config commands
mac-address Manually set interface MAC address
mtu Set the interface Maximum Transmission Unit (MTU)
no Negate a command or set its defaults
priority-group Assign a priority group to an interface
service-policy Configure QoS Service Policy
shutdown Shutdown the selected interface
speed Set allowed radio bit rates
ssid Configure radio service set parameters
tx-ring-limit Configure PA level transmit ring limit
i'll consider the problem *mostly* solved. I was able to assign the SSD.
The infrastructure command may be expendable in this case... to be determined
here is our configuration for R3
R3#
show run
Building configuration...
Current configuration : 1682 bytes
!
version 15.1
no service timestamps log datetime msec
no service timestamps debug datetime msec
no service password-encryption
!
hostname R3
!
!
!
enable secret 5 $1$mERr$V5ujdIM9bTB/I.ipB0gkJ0
!
!
ip dhcp excluded-address 172.16.10.1 172.16.10.10
!
ip dhcp pool Admin
network 172.16.10.0 255.255.255.0
default-router 172.16.10.1
!
dot11 ssid ADMIN
authentication open
guest-mode
!
dot11 ssid ADMIN2
authentication open
guest-mode
!
!
!
ip cef
no ipv6 cef
!
!
!
!
license udi pid CISCO2811/K9 sn FTX1017RE40-
!
!
!
!
!
!
!
!
!
no ip domain-lookup
ip name-server 172.16.10.4
!
!
spanning-tree mode pvst
!
!
!
!
!
!
interface FastEthernet0/0
description connection to corp router
ip address 10.1.5.2 255.255.255.0
duplex auto
speed auto
!
interface FastEthernet0/1
no ip address
duplex auto
speed auto
shutdown
!
interface Dot11Radio0/0/0
description WAN for mobile
ip address 172.16.10.1 255.255.255.0
speed 12.0 18.0 24.0 36.0 48.0 54.0 6.0 9.0 basic-1.0 basic-11.0 basic-2.0 basic-5.5
ssid ADMIN2
!
interface Dot11Radio0/0/1
no ip address
speed 18.0 36.0 48.0 54.0 9.0 basic-12.0 basic-24.0 basic-6.0
!
interface Serial0/1/0
no ip address
clock rate 2000000
!
interface Serial0/1/1
no ip address
clock rate 2000000
!
interface Vlan1
no ip address
shutdown
!
router rip
version 2
network 10.0.0.0
network 172.16.0.0
!
ip classless
ip route 0.0.0.0 0.0.0.0 10.1.5.1
!
ip flow-export version 9
!
!
!
banner motd ^C this is R3 $
this is R3 ^C
!
!
!
!
!
line con 0
exec-timeout 0 0
password console
logging synchronous
login
!
line aux 0
password aux
login
!
line vty 0 4
password telnet
login
line vty 5 15
password telnet
login
!
!
!
end
to summarize...
the book is a little off here.
-----------------------------------------------------------------------------------------------
R3(config-if)#
int dot11radio0/0/0
R3(config-if)#
ip address 172.16.10.1 255.255.255.0
R3(config-if)#
description WLAN for mobile user
R3(config-if)#
no shut
at this point we have created a wireless interface with an IP address but no SSID exists on this router
interface Dot11Radio0/0/0
description test router 2
ip address 172.16.10.1 255.255.255.0
speed 12.0 18.0 24.0 36.0 48.0 54.0 6.0 9.0 basic-1.0 basic-11.0 basic-2.0 basic-5.5
Trying to use the command "ssid ADMIN" doesnt work here. The below commands are invalid here:
R3(config-if)#
ssid ADMIN
R3(config-if-ssid)#
guest-mode
R3(config-if-ssid)#
authentication open
R3(config-if-ssid)#
ingrastructure-ssid
R3(config-if-ssid)#
exit
-----------------------------------------------------------------------------------------------
We need to drop out of config-if, back to config, and enter SSID config mode
-----------------------------------------------------------------------------------------------
R3(config-if)#
exit
R3(config)#
dot11 ssid ADMIN2 creates an ssid named ADMIN2, and puts us into SSID config mode
R3(config-ssid)#
guest-mode
R3(config-ssid)#
authentication open
then out of config-ssid and back to interface config
R3(config-ssid)#
exit
R3(config)
int dot11r0/0/0
R3(config-if)
?
arp Set arp type (arpa, probe, snap) or timeout or log options
bandwidth Set bandwidth informational parameter
cdp CDP interface subcommands
crypto Encryption/Decryption commands
delay Specify interface throughput delay
description Interface specific description
encryption Configure dot11 encryption parameters
exit Exit from interface configuration mode
fair-queue Enable Fair Queuing on an Interface
hold-queue Set hold queue depth
ip Interface Internet Protocol config commands
mac-address Manually set interface MAC address
mtu Set the interface Maximum Transmission Unit (MTU)
no Negate a command or set its defaults
priority-group Assign a priority group to an interface
service-policy Configure QoS Service Policy
shutdown Shutdown the selected interface
speed Set allowed radio bit rates
ssid Configure radio service set parameters
tx-ring-limit Configure PA level transmit ring limit
we have the option for ssid
R3(config-if)
ssid ADMIN2
%LINK-5-CHANGED: Interface Dot11Radio0/0/0, changed state to administratively down
%LINEPROTO-5-UPDOWN: Line protocol on Interface Dot11Radio0/0/0, changed state to down
%LINK-5-CHANGED: Interface Dot11Radio0/0/0, changed state to up
%LINEPROTO-5-UPDOWN: Line protocol on Interface Dot11Radio0/0/0, changed state to up
the router resets the interface..
-----------------------------------------------------------------------------------------------
R3(config-if)
do show run
[cut]
!
!
dot11 ssid ADMIN2
authentication open
guest-mode
!
!
[cut]
!
interface Dot11Radio0/0/0
description test router 2
ip address 172.16.10.1 255.255.255.0
speed 12.0 18.0 24.0 36.0 48.0 54.0 6.0 9.0 basic-1.0 basic-11.0 basic-2.0 basic-5.5
ssid ADMIN2
!
[cut]
the SSID is created and assigned to the interface
To summarize.
Wrong: create the dot11 interface, then create the SSID from CONFIG-IF mode, which puts you into CONFIG-IF-SSID (there is no such mode on this router) mode, then modify the ssid from there...
Correct: create the dot11 interface. Exit CONFIG-IF and go back to GLOBAL CONFIG. Create the SSID which puts you in CONFIG-SSID mode.
Configure the ssid. Then exit CONFIG-SSID. Back into CONFIG-IF, assign the SSID
We have one more task for R3- Configuring the DHCP pool for wireless clients.
R3(config)#
ip dhcp pool Admin creating the pool name as "Admin"
R3(dhcp-config)#
network 172.16.10.0 255.255.255.0
R3(dhcp-config)#
default-router 172.16.10.1 aka default-gateway for clients in the pool
R3(dhcp-config)#
ip name-server 172.16.10.4 dns server
*automatically exits dhcp-config prompt*
R3(config)#
ip dhcp excluded-address 172.16.10.1 172.16.10.10 excludes the range given
172.16.10.1 is the router interface- we need to specifically exclude it from the pool
this setup should allow the wireless client to pick up an IP after connecting to the open SSID.
However, I was having trouble at first-
even though I seemed to have the SSID set correctly, i was hitting a WEP password prompt
i didnt see any obvious issues with the wifi module im using on the laptop:
The Linksys-WPC300N module provides one 2.4GHz wireless interface suitable for connection to wireless networks.
The module supports protocols that use Ethernet for LAN access.
I ended up creating a new SSID, with the same settings as the original:
R3(config)#
dot11 ssid ADMIN2
R3(config-ssid)#
guest-mode
R3(config-ssid)#
authentication open
and then I assigned the ip address to ssid ADMIN2 instead of the orginal ADMIN ssid
R3(config)#
int dot110/0/0
R3(config-if)#
ip address 172.16.10.1 255.255.255.0
R3(config-if)#
description WLAN for mobile user
R3(config-if)#
no shut
R3(config-if)#
ssid ADMIN2
R3#
show run
Building configuration...
Current configuration : 1467 bytes
!
version 15.1
no service timestamps log datetime msec
no service timestamps debug datetime msec
no service password-encryption
!
hostname R3
!
!
!
enable secret 5 $1$mERr$V5ujdIM9bTB/I.ipB0gkJ0
!
!
ip dhcp excluded-address 172.16.10.1 172.16.10.10
!
ip dhcp pool Admin
network 172.16.10.0 255.255.255.0
default-router 172.16.10.1
!
dot11 ssid ADMIN
authentication open
guest-mode
!
dot11 ssid ADMIN2
authentication open
guest-mode
!
!
!
ip cef
no ipv6 cef
!
!
!
!
license udi pid CISCO2811/K9 sn FTX1017RE40-
!
!
!
!
!
!
!
!
!
no ip domain-lookup
ip name-server 172.16.10.4
!
!
spanning-tree mode pvst
!
!
!
!
!
!
interface FastEthernet0/0
description connection to corp router
ip address 10.1.5.2 255.255.255.0
duplex auto
speed auto
!
interface FastEthernet0/1
no ip address
duplex auto
speed auto
shutdown
!
interface Dot11Radio0/0/0
description WAN for mobile
ip address 172.16.10.1 255.255.255.0
speed 12.0 18.0 24.0 36.0 48.0 54.0 6.0 9.0 basic-1.0 basic-11.0 basic-2.0 basic-5.5
ssid ADMIN2
!
interface Dot11Radio0/0/1
no ip address
speed 18.0 36.0 48.0 54.0 9.0 basic-12.0 basic-24.0 basic-6.0
!
interface Vlan1
no ip address
shutdown
!
ip classless
!
ip flow-export version 9
!
!
!
banner motd ^C this is R3 $
this is R3 ^C
!
!
!
!
!
line con 0
exec-timeout 0 0
password console
logging synchronous
login
!
line aux 0
password aux
login
!
line vty 0 4
password telnet
login
line vty 5 15
password telnet
login
!
!
!
end
Recall the DHCP configuration on R3:
R3(config)#
ip dhcp pool Admin creating the pool name as "Admin"
R3(dhcp-config)#
network 172.16.10.0 255.255.255.0
R3(dhcp-config)#
default-router 172.16.10.1 aka default-gateway for clients in the pool
R3(dhcp-config)#
ip name-server 172.16.10.4 dns server
*automatically exits dhcp-config prompt*
R3(config)#
ip dhcp excluded-address 172.16.10.1 172.16.10.10 excludes the range given
172.16.10.1 is the router interface- we need to specifically exclude it from the pool
we can check the configuration:
R3#
show ip dhcp pool
Pool Admin :
Utilization mark (high/low) : 100 / 0
Subnet size (first/next) : 0 / 0
Total addresses : 254
Leased addresses : 1
Excluded addresses : 1
Pending event : none
1 subnet is currently in the pool
Current index IP address range Leased/Excluded/Total
172.16.10.1 172.16.10.1 - 172.16.10.254 1 / 1 / 254
R3#
show ip dhcp binding
IP address Client-ID/ Lease expiration Type
Hardware address
172.16.10.11 00D0.979A.733B -- Automatic
the show command is becoming more familiar
R3#
show ip?
access-lists List access lists
arp IP ARP table
bgp BGP information
cache IP fast-switching route cache
cef Cisco Express Forwarding
dhcp Show items in the DHCP database
eigrp IP-EIGRP show commands
inspect CBAC (Context Based Access Control) information
interface IP interface status and configuration
ips IPS (Intrusion Prevention System) information
nat IP NAT information
nbar Network-Based Application Recognition
ospf OSPF information
protocols IP routing protocol process parameters and statistics
rip IP RIP show commands
route IP routing table
ssh Information on SSH
we'll use show ip route soon on all the routers. For now, here is the output for R3:
R3#
show ip route
Codes: L - local, C - connected, S - static, R - RIP, M - mobile, B - BGP
D - EIGRP, EX - EIGRP external, O - OSPF, IA - OSPF inter area
N1 - OSPF NSSA external type 1, N2 - OSPF NSSA external type 2
E1 - OSPF external type 1, E2 - OSPF external type 2, E - EGP
i - IS-IS, L1 - IS-IS level-1, L2 - IS-IS level-2, ia - IS-IS inter area
* - candidate default, U - per-user static route, o - ODR
P - periodic downloaded static route
Gateway of last resort is not set
10.0.0.0/8 is variably subnetted, 2 subnets, 2 masks
C 10.1.5.0/24 is directly connected, FastEthernet0/0
L 10.1.5.2/32 is directly connected, FastEthernet0/0
172.16.0.0/16 is variably subnetted, 2 subnets, 2 masks
C 172.16.10.0/24 is directly connected, Dot11Radio0/0/0
L 172.16.10.1/32 is directly connected, Dot11Radio0/0/0
Before moving on to the routing configurations, here is a review of the topology
I have switched over to the DrawIO diagram app to lay out the topology.
The Packet Tracer diagram becomes
too crowded to see the labels; it's labeling system forces awkward positioning of the objects; the interface
label's cant be moved, so if objects are too close together their labels cover eachother.. not good.
DrawIO allows a cleaner layout with plenty of room to label interfaces and ip addresses.
As a compromise, I'll use both.
I have the packet tracer objects spread out just enough to see the interfaces
and the label for each router. From here I can jump into the CLI for each device.
The DrawIO diagram allows me to cleary see IP addresses
I want to also review all of the configurations we just performed:
PROBLEM
The book specifies that of the two serial conections between R1 and Corp, there should be a DCE on each end..
Both of my DCE's are on the same end.
First lets be sure we understand what DCE means:
networkengineering.stackexchange.com/
One side of the link (DCE), has to transmit the clock signal, which controls the data rate, and the other side (DTE) receives the clock signal.
That is good enough for now. Note that while the book does specify in the diagram that each side should have a DCE, it was not actually mentioned in the configs.
We did not set a DCE or clock rate when conifguring those interfaces.
To fix this in my Packet Tracer topology, I did some quick research:
While this post wasnt pertaining to Packet Tracer, it got me thinking about the cable itself.
I deleted both of my existing serial connections and looked at the options for creating a new cable.
I noticed one is a DCE and one is a DTE:
Fixed the issue
back to the configuration overview: 4 routers, abbreviated show run output
Corp
interface FastEthernet0/0
description connection to R3
ip address 10.1.5.1 255.255.255.0
duplex auto
speed auto
!
interface FastEthernet0/1
no ip address
duplex auto
speed auto
shutdown
!
interface Serial0/0/0
description 1st connection to R1
ip address 10.1.2.1 255.255.255.0
!
interface Serial0/0/1
description 2nd connection to R1
ip address 10.1.3.1 255.255.255.0
clock rate 2000000
!
interface Serial0/1/0
description connection to R2
ip address 10.1.4.1 255.255.255.0
!
interface Vlan1
description Switch Card to Core Network
ip address 10.1.1.1 255.255.255.0
!
interface FastEthernet1/0
description switch port connection to WWW Server
switchport mode access
switchport nonegotiate
!
interface FastEthernet1/1
description switch port connection to Email Server
switchport mode access
switchport nonegotiate
!
interface FastEthernet1/2
description switch port connection to DNS Server
switchport mode access
switchport nonegotiate
!
R1
interface FastEthernet0/0
description connection to Finance
ip address 192.168.10.1 255.255.255.0
duplex auto
speed auto
!
interface FastEthernet0/1
description connection to Marketing
ip address 192.168.20.1 255.255.255.0
duplex auto
speed auto
!
interface Serial0/0/0
description 1st connection to Corp router
ip address 10.1.2.2 255.255.255.0
clock rate 2000000
!
interface Serial0/0/1
description 2nd connecction to Corp router
ip address 10.1.3.2 255.255.255.0
!
R2
interface FastEthernet0/0
description Connection to Sales PC
ip address 192.168.30.1 255.255.255.0
duplex auto
speed auto
!
interface FastEthernet0/1
description Connection to HR PC
ip address 192.168.40.1 255.255.255.0
duplex auto
speed auto
!
interface Serial0/0/0
description Connection to Corp Router
ip address 10.1.4.2 255.255.255.0
clock rate 2000000
!
interface Serial0/0/1
no ip address
clock rate 2000000
shutdown
!
R3
interface FastEthernet0/0
description connection to corp router
ip address 10.1.5.2 255.255.255.0
duplex auto
speed auto
!
interface FastEthernet0/1
no ip address
duplex auto
speed auto
shutdown
!
interface Dot11Radio0/0/0
description WAN for mobile
ip address 172.16.10.1 255.255.255.0
speed 12.0 18.0 24.0 36.0 48.0 54.0 6.0 9.0 basic-1.0 basic-11.0 basic-2.0 basic-5.5
ssid ADMIN2
and here is the output of show ip route for each router
Codes: C - connected, S - static, I - IGRP, R - RIP, M - mobile, B - BGP
D - EIGRP, EX - EIGRP external, O - OSPF, IA - OSPF inter area
N1 - OSPF NSSA external type 1, N2 - OSPF NSSA external type 2
E1 - OSPF external type 1, E2 - OSPF external type 2, E - EGP
i - IS-IS, L1 - IS-IS level-1, L2 - IS-IS level-2, ia - IS-IS inter area
* - candidate default, U - per-user static route, o - ODR
P - periodic downloaded static route
Gateway of last resort is not set
Corp
10.0.0.0/24 is subnetted, 2 subnets
C 10.1.2.0 is directly connected, Serial0/0/0
C 10.1.3.0 is directly connected, Serial0/0/1
C 192.168.10.0/24 is directly connected, FastEthernet0/0
C 192.168.20.0/24 is directly connected, FastEthernet0/1
R1
10.0.0.0/24 is subnetted, 2 subnets
C 10.1.2.0 is directly connected, Serial0/0/0
C 10.1.3.0 is directly connected, Serial0/0/1
C 192.168.10.0/24 is directly connected, FastEthernet0/0
C 192.168.20.0/24 is directly connected, FastEthernet0/1
R2
10.0.0.0/24 is subnetted, 1 subnets
C 10.1.4.0 is directly connected, Serial0/0/0
C 192.168.30.0/24 is directly connected, FastEthernet0/0
C 192.168.40.0/24 is directly connected, FastEthernet0/1
R3
10.0.0.0/8 is variably subnetted, 2 subnets, 2 masks
C 10.1.5.0/24 is directly connected, FastEthernet0/0
L 10.1.5.2/32 is directly connected, FastEthernet0/0
172.16.0.0/16 is variably subnetted, 2 subnets, 2 masks
C 172.16.10.0/24 is directly connected, Dot11Radio0/0/0
L 172.16.10.1/32 is directly connected, Dot11Radio0/0/0
Note that this is before we have configured any 'routing'. We are seeing configured, directly connected networks.
The output for R3 is particularly interesting
What does 'variably' subnetted mean, and what is the "L" next to these routes. And why do they have a mask of 32?
R3
10.0.0.0/8 is variably subnetted, 2 subnets, 2 masks
C 10.1.5.0/24 is directly connected, FastEthernet0/0
L 10.1.5.2/32 is directly connected, FastEthernet0/0
172.16.0.0/16 is variably subnetted, 2 subnets, 2 masks
C 172.16.10.0/24 is directly connected, Dot11Radio0/0/0
L 172.16.10.1/32 is directly connected, Dot11Radio0/0/0
Cisco forums
That makes sense, but my question is why did the other routing tables not behave the same way? R3 is the only one that shows "L" routes.
The book tells us we're using two different model routers, and indeed they are running different IOS versions:
NOTE that at the time the book was published IOS 15 was not released yet, so the book assumes all routers are running 12.4
But that still doesnt explain why Corp and R3 are behaving differently..
Corp
10.0.0.0/24 is subnetted, 2 subnets
C 10.1.2.0 is directly connected, Serial0/0/0
C 10.1.3.0 is directly connected, Serial0/0/1
C 192.168.10.0/24 is directly connected, FastEthernet0/0
C 192.168.20.0/24 is directly connected, FastEthernet0/1
R1
10.0.0.0/24 is subnetted, 2 subnets
C 10.1.2.0 is directly connected, Serial0/0/0
C 10.1.3.0 is directly connected, Serial0/0/1
C 192.168.10.0/24 is directly connected, FastEthernet0/0
C 192.168.20.0/24 is directly connected, FastEthernet0/1
R2
10.0.0.0/24 is subnetted, 1 subnets
C 10.1.4.0 is directly connected, Serial0/0/0
C 192.168.30.0/24 is directly connected, FastEthernet0/0
C 192.168.40.0/24 is directly connected, FastEthernet0/1
R3
10.0.0.0/8 is variably subnetted, 2 subnets, 2 masks
C 10.1.5.0/24 is directly connected, FastEthernet0/0
L 10.1.5.2/32 is directly connected, FastEthernet0/0
172.16.0.0/16 is variably subnetted, 2 subnets, 2 masks
C 172.16.10.0/24 is directly connected, Dot11Radio0/0/0
L 172.16.10.1/32 is directly connected, Dot11Radio0/0/0
how are Corp and R3 different?
The answer is, they are not...
I have accidentally displayed the R1 output to the Corp windows. Error in translating data from the IOS to this webpage..
here's the corrected output.
Corp
10.0.0.0/8 is variably subnetted, 10 subnets, 2 masks
C 10.1.1.0/24 is directly connected, Vlan1
L 10.1.1.1/32 is directly connected, Vlan1
C 10.1.2.0/24 is directly connected, Serial0/0/0
L 10.1.2.1/32 is directly connected, Serial0/0/0
C 10.1.3.0/24 is directly connected, Serial0/0/1
L 10.1.3.1/32 is directly connected, Serial0/0/1
C 10.1.4.0/24 is directly connected, Serial0/1/0
L 10.1.4.1/32 is directly connected, Serial0/1/0
C 10.1.5.0/24 is directly connected, FastEthernet0/0
L 10.1.5.1/32 is directly connected, FastEthernet0/0
R1
10.0.0.0/24 is subnetted, 2 subnets
C 10.1.2.0 is directly connected, Serial0/0/0
C 10.1.3.0 is directly connected, Serial0/0/1
C 192.168.10.0/24 is directly connected, FastEthernet0/0
C 192.168.20.0/24 is directly connected, FastEthernet0/1
R2
10.0.0.0/24 is subnetted, 1 subnets
C 10.1.4.0 is directly connected, Serial0/0/0
C 192.168.30.0/24 is directly connected, FastEthernet0/0
C 192.168.40.0/24 is directly connected, FastEthernet0/1
R3
10.0.0.0/8 is variably subnetted, 2 subnets, 2 masks
C 10.1.5.0/24 is directly connected, FastEthernet0/0
L 10.1.5.2/32 is directly connected, FastEthernet0/0
172.16.0.0/16 is variably subnetted, 2 subnets, 2 masks
C 172.16.10.0/24 is directly connected, Dot11Radio0/0/0
L 172.16.10.1/32 is directly connected, Dot11Radio0/0/0
We do indeed see consistent behavior differences between IOS versions 12.4 and 15.1
recap Corp and R3 outputs:
update topology with Router versions
That covers the first half of Chapter 8. Now we are ready to configure IP routing on our network.
There are three ways: Static, Default, Dynamic
To set up static routes, we simply need to program the routes using the ip route command
Syntax
ip route
[
destination network
]
[
mask
]
[
next hop
]
[
exitinterface
]
[
administrative distance
]
[
permanent
]
destination network and mask
the network data we're adding to the routing table
next-hop address
the address of the next-hop router that will receive the packet and forward to the remote network.
This is the IP address of a router interface that is directly connected.
It must be pingable.
exit interface
can be used instead of next hop address
administrative distance
by default, static routes have an admin distance of 1 if you use a next hop, or 0 if you use exit interface.
You can change the value by adding an administrative weight at the end of the command. More on this later with dynamic routing.
permanent
if the interface is shut down or the router cant communicate to the next hp router, the route will automatically be discarded from the table by default.
The 'permanent' option keeps the entry in the routing table indefenitely.
-----------------------------------------------------------------------------------------------------
Corp has automatically picked up 5 routes that are directly connected:
10.1.1.0 to corp switch card
10.1.2.0 to R1
10.1.3.0 to R1
10.1.4.0 to R2
10.1.5.0 to R3
We need to program 5 more routes:
192.168.10.0 traverse R1
192.168.20.0 traverse R1
192.168.30.0 traverse R1
192.168.40.0 traverse R2
172.16.10.0 traverse R3
-----------------------------------------------------------------------------------------------------
R1 has automatically picked up 4 routes that are directly connected:
10.1.2.0
10.1.3.0
192.168.10.0
192.168.20.0
We need to program 6 more routes:
10.1.1.0
10.1.4.0
10.1.5.0
192.168.30.0
192.168.40.0
172.16.10.0
-----------------------------------------------------------------------------------------------------
R2 has automatically picked up 3 routes that are directly connected:
10.1.4.0
192.168.30.0
192.168.40.0
We need to program 7 more routes:
10.1.1.0
10.1.2.0
10.1.3.0
10.1.5.0
192.168.10.0
192.168.20.0
172.16.10.0
-----------------------------------------------------------------------------------------------------
R3 has automatically picked up 2 routes that are directly connected:
10.1.5.0
172.16.10.0
We need to program 8 more routes:
10.1.1.0
10.1.2.0
10.1.3.0
10.1.4.0
192.168.10.0
192.168.20.0
192.168.30.0
192.168.40.0
Notice the pattern- each router ends up with 10 routes
There are 10 routes total in this topology. AKA ten broadcast domains
Programming the routes
Corp
Corp(config)#
ip route 192.168.10.0 255.255.255.0 10.1.2.2 150
Corp(config)#
ip route 192.168.20.0 255.255.255.0 10.1.3.2 150
Corp(config)#
ip route 192.168.30.0 255.255.255.0 10.1.4.2 150
Corp(config)#
ip route 192.168.40.0 255.255.255.0 10.1.4.2 150
Corp(config)#
ip route 172.16.10.0 255.255.255.0 10.1.5.2 150
Corp(config)#
do show ip route
In the first line, the router is saying that a
classful A network is being subnetted
There are 5 routes directly connected
We see two lines per route (one for the network and one
for the interface(/32)-
10.0.0.0/8 is variably subnetted, 10 subnets, 2 masks
C 10.1.1.0/24 is directly connected, Vlan1
L 10.1.1.1/32 is directly connected, Vlan1
C 10.1.2.0/24 is directly connected, Serial0/0/0
L 10.1.2.1/32 is directly connected, Serial0/0/0
C 10.1.3.0/24 is directly connected, Serial0/0/1
L 10.1.3.1/32 is directly connected, Serial0/0/1
C 10.1.4.0/24 is directly connected, Serial0/1/0
L 10.1.4.1/32 is directly connected, Serial0/1/0
C 10.1.5.0/24 is directly connected, FastEthernet0/0
L 10.1.5.1/32 is directly connected, FastEthernet0/0
and 5 routes that require traversal of a router to reach
172.16.0.0/24 is subnetted, 1 subnets
S 172.16.10.0/24 [150/0] via 10.1.5.2
S 192.168.10.0/24 [150/0] via 10.1.2.2
S 192.168.20.0/24 [150/0] via 10.1.3.2
S 192.168.30.0/24 [150/0] via 10.1.4.2
S 192.168.40.0/24 [150/0] via 10.1.4.2
R1
R1(config)#
ip route 10.1.1.0 255.255.255.0 10.1.2.1 150
R1(config)#
ip route 10.1.4.0 255.255.255.0 10.1.3.1 150
R1(config)#
ip route 10.1.5.0 255.255.255.0 10.1.2.1 150
R1(config)#
ip route 192.168.30.0 255.255.255.0 10.1.3.1 150
R1(config)#
ip route 192.168.40.0 255.255.255.0 10.1.2.1 150
R1(config)#
ip route 172.16.10.0 255.255.255.0 10.1.3.1 150
the only way to get across the corp router is to go into it via 10.1.2.1 or 10.1.3.1
R1(config)#
do show ip route
10.0.0.0/24 is subnetted, 5 subnets
S 10.1.1.0 [150/0] via 10.1.2.1
C 10.1.2.0 is directly connected, Serial0/0/0
C 10.1.3.0 is directly connected, Serial0/0/1
S 10.1.4.0 [150/0] via 10.1.3.1
S 10.1.5.0 [150/0] via 10.1.2.1
172.16.0.0/24 is subnetted, 1 subnets
S 172.16.10.0 [150/0] via 10.1.3.1
C 192.168.10.0/24 is directly connected, FastEthernet0/0
C 192.168.20.0/24 is directly connected, FastEthernet0/1
S 192.168.30.0/24 [150/0] via 10.1.3.1
S 192.168.40.0/24 [150/0] via 10.1.2.1
R2
R2(config)#
iproute 10.1.1.0 255.255.255.0 10.1.4.1 150
R2(config)#
iproute 10.1.2.0 255.255.255.0 10.1.4.1 150
R2(config)#
iproute 10.1.3.0 255.255.255.0 10.1.4.1 150
R2(config)#
iproute 10.1.5.0 255.255.255.0 10.1.4.1 150
R2(config)#
iproute 192.168.10.0 255.255.255.0 10.1.4.1 150
R2(config)#
iproute 192.168.20.0 255.255.255.0 10.1.4.1 150
the only way to get across Corp is to go into it via 10.1.4.1
R2(config)#
do show ip route
10.0.0.0/24 is subnetted, 5 subnets
S 10.1.1.0 [150/0] via 10.1.4.1
S 10.1.2.0 [150/0] via 10.1.4.1
S 10.1.3.0 [150/0] via 10.1.4.1
C 10.1.4.0 is directly connected, Serial0/0/0
S 10.1.5.0 [150/0] via 10.1.4.1
172.16.0.0/24 is subnetted, 1 subnets
S 172.16.10.0 [150/0] via 10.1.4.1
S 192.168.10.0/24 [150/0] via 10.1.4.1
S 192.168.20.0/24 [150/0] via 10.1.4.1
C 192.168.30.0/24 is directly connected, FastEthernet0/0
C 192.168.40.0/24 is directly connected, FastEthernet0/1
R3
R3(config)#
ip route 10.1.1.0 255.255.255.0 fastethernet 0/0 150
R3(config)#
ip route 10.1.2.0 255.255.255.0 fastethernet 0/0 150
R3(config)#
ip route 10.1.3.0 255.255.255.0 fastethernet 0/0 150
R3(config)#
ip route 10.1.4.0 255.255.255.0 fastethernet 0/0 150
R3(config)#
ip route 192.168.10.0 255.255.255.0 fastethernet 0/0 150
R3(config)#
ip route 192.168.20.0 255.255.255.0 fastethernet 0/0 150
R3(config)#
ip route 192.168.30.0 255.255.255.0 fastethernet 0/0 150
R3(config)#
ip route 192.168.40.0 255.255.255.0 fastethernet 0/0 150
the only way to get across Corp is to EXIT R3 via F0/0
R3(config)#
do show ip route
10.0.0.0/8 is variably subnetted, 6 subnets, 2 masks
S 10.1.1.0/24 is directly connected, FastEthernet0/0
S 10.1.2.0/24 is directly connected, FastEthernet0/0
S 10.1.3.0/24 is directly connected, FastEthernet0/0
S 10.1.4.0/24 is directly connected, FastEthernet0/0
C 10.1.5.0/24 is directly connected, FastEthernet0/0
L 10.1.5.2/32 is directly connected, FastEthernet0/0
172.16.0.0/16 is variably subnetted, 2 subnets, 2 masks
C 172.16.10.0/24 is directly connected, Dot11Radio0/0/0
L 172.16.10.1/32 is directly connected, Dot11Radio0/0/0
S 192.168.10.0/24 is directly connected, FastEthernet0/0
S 192.168.20.0/24 is directly connected, FastEthernet0/0
S 192.168.30.0/24 is directly connected, FastEthernet0/0
S 192.168.40.0/24 is directly connected, FastEthernet0/0
before verifying connectivity across the network, we need to make sure all of our hosts are set. The book is giving us the IP addresses for the servers:
Server Gateway 10.1.1.1
ServerWeb 10.1.1.2
ServerEmail 10.1.1.3
ServerDNS 10.1.1.4
Now we can do some testing across the network:
R3#
ping 10.1.2.2
traverse Corp to R1
R3#
ping 10.1.1.1
traverse Corp to a Corp interface we arent directly connected to
R3#
ping 10.1.1.2
traverse Corp to Web server
R3#
ping 10.1.1.3
traverse Corp to Email server
R3#
ping 10.1.1.4
traverse Corp to DNS server
MobileUser
ping 192.168.10.2
traverse R3, Corp, R1 to Finance client
MobileUser
tracert 192.168.10.2
traverse R3, Corp, R1 to Finance client
Tracing route to 192.168.10.2 over a maximum of 30 hops:
1 19 ms 5 ms 20 ms 172.16.10.1
2 20 ms 6 ms 11 ms 10.1.5.1
3 11 ms 15 ms 10 ms 10.1.3.2
4 9 ms 13 ms 22 ms 192.168.10.2
Trace complete.
notice how the trace doesnt count an egress as a hop, only an ingress
ALSO NOTE that tracert is a Windows command.
the IOS equivalent is traceroute
notice how the output differs from the Windows command
R3
traceroute 192.168.10.2
Type escape sequence to abort.
Tracing the route to 192.168.10.2
1 10.1.5.1 0 msec 0 msec 0 msec
2 10.1.2.2 6 msec 0 msec 5 msec
3 192.168.10.2 1 msec 4 msec 3 msec
Default Routing
we could have done this on R3
R3(config)#
ip route 0.0.0.0 0.0.0.0 10.1.5.1
as an alternative to this configuration on R3
R3(config)#
ip route 10.1.1.0 255.255.255.0 fastethernet 0/0 150
R3(config)#
ip route 10.1.2.0 255.255.255.0 fastethernet 0/0 150
R3(config)#
ip route 10.1.3.0 255.255.255.0 fastethernet 0/0 150
R3(config)#
ip route 10.1.4.0 255.255.255.0 fastethernet 0/0 150
R3(config)#
ip route 192.168.10.0 255.255.255.0 fastethernet 0/0 150
R3(config)#
ip route 192.168.20.0 255.255.255.0 fastethernet 0/0 150
R3(config)#
ip route 192.168.30.0 255.255.255.0 fastethernet 0/0 150
R3(config)#
ip route 192.168.40.0 255.255.255.0 fastethernet 0/0 150
the only way to get across Corp is to EXIT R3 via F0/0
This is called default routing. It should only be used on 'stub routers'- those with only one exit path out of the network.
if you try to put a default route on a non-stub router, you could create loops, since there will be more than one path to other routers...
Think of a default route as a static route that uses a wildcard address and mask. The wildcard is 0.0.0.0
to further analyze this comparison, I'm going to remove the routes from R3...
R3(config)#
no ip route 10.1.1.0 255.255.255.0 fastethernet0/0 150
R3(config)#
no ip route 10.1.2.0 255.255.255.0 fastethernet0/0 150
R3(config)#
no ip route 10.1.3.0 255.255.255.0 fastethernet0/0 150
R3(config)#
no ip route 10.1.4.0 255.255.255.0 fastethernet0/0 150
R3(config)#
no ip route 192.168.10.0 255.255.255.0 fastethernet0/0 150
R3(config)#
no ip route 192.168.20.0 255.255.255.0 fastethernet0/0 150
R3(config)#
no ip route 192.168.30.0 255.255.255.0 fastethernet0/0 150
R3(config)#
no ip route 192.168.40.0 255.255.255.0 fastethernet0/0 150
and then set the default route instead.
R3#
ip route 0.0.0.0 0.0.0.0 10.1.5.1 --- ingress at next hop
OR
R3#
ip route 0.0.0.0 0.0.0.0 Fa0/0 --- egress interface
Then compare the output of show ip route
static routes set
R3#
show ip route
Gateway of last resort is not set
10.0.0.0/8 is variably subnetted, 6 subnets, 2 masks
S 10.1.1.0/24 is directly connected, FastEthernet0/0
S 10.1.2.0/24 is directly connected, FastEthernet0/0
S 10.1.3.0/24 is directly connected, FastEthernet0/0
S 10.1.4.0/24 is directly connected, FastEthernet0/0
C 10.1.5.0/24 is directly connected, FastEthernet0/0
L 10.1.5.2/32 is directly connected, FastEthernet0/0
172.16.0.0/16 is variably subnetted, 2 subnets, 2 masks
C 172.16.10.0/24 is directly connected, Dot11Radio0/0/0
L 172.16.10.1/32 is directly connected, Dot11Radio0/0/0
S 192.168.10.0/24 is directly connected, FastEthernet0/0
S 192.168.20.0/24 is directly connected, FastEthernet0/0
S 192.168.30.0/24 is directly connected, FastEthernet0/0
S 192.168.40.0/24 is directly connected, FastEthernet0/0
default route set
R3#
show ip route
Gateway of last resort is 10.1.5.1 to network 0.0.0.0
10.0.0.0/8 is variably subnetted, 2 subnets, 2 masks
C 10.1.5.0/24 is directly connected, FastEthernet0/0
L 10.1.5.2/32 is directly connected, FastEthernet0/0
172.16.0.0/16 is variably subnetted, 2 subnets, 2 masks
C 172.16.10.0/24 is directly connected, Dot11Radio0/0/0
L 172.16.10.1/32 is directly connected, Dot11Radio0/0/0
S* 0.0.0.0/0 [1/0] via 10.1.5.1
two directly connected networks- 10.1.5.0 and 172.16.10.0
anything not included in those networks goes to ingress of attached neighbor Corp 10.1.5.1
in this toplogy, that includes:
192.168.10.0
192.168.20.0
192.168.30.0
192.168.40.0
and
10.1.1.0
10.1.2.0
10.1.3.0
10.1.4.0
RIP Routing Information Protocol
R1(config)#
router ?
bgp Border Gateway Protocol (BGP)
eigrp Enhanced Interior Gateway Routing Protocol (EIGRP)
ospf Open Shortest Path First (OSPF)
rip Routing Information Protocol (RIP)
set RIP on Corp
Corp(config)#
router rip
Corp(config-router)#
network 10.0.0.0
set RIP on R1
R1(config)#
router rip
R1(config-router)#
network 10.0.0.0
R1 routing table
R1(config)#
do show ip route
10.0.0.0/24 is subnetted, 5 subnets
R 10.1.1.0 [120/1] via 10.1.2.1, 00:00:21, Serial0/0/0
[120/1] via 10.1.3.1, 00:00:21, Serial0/0/1
C 10.1.2.0 is directly connected, Serial0/0/0
C 10.1.3.0 is directly connected, Serial0/0/1
R 10.1.4.0 [120/1] via 10.1.2.1, 00:00:21, Serial0/0/0
[120/1] via 10.1.3.1, 00:00:21, Serial0/0/1
R 10.1.5.0 [120/1] via 10.1.2.1, 00:00:21, Serial0/0/0
[120/1] via 10.1.3.1, 00:00:21, Serial0/0/1
172.16.0.0/24 is subnetted, 1 subnets
S 172.16.10.0 [150/0] via 10.1.3.1
C 192.168.10.0/24 is directly connected, FastEthernet0/0
C 192.168.20.0/24 is directly connected, FastEthernet0/1
S 192.168.30.0/24 [150/0] via 10.1.3.1
S 192.168.40.0/24 [150/0] via 10.1.2.1
here's R1 before RIP, with only static routes set:
R1(config)#
do show ip route
10.0.0.0/24 is subnetted, 5 subnets
S 10.1.1.0 [150/0] via 10.1.2.1
C 10.1.2.0 is directly connected, Serial0/0/0
C 10.1.3.0 is directly connected, Serial0/0/1
S 10.1.4.0 [150/0] via 10.1.3.1
S 10.1.5.0 [150/0] via 10.1.2.1
172.16.0.0/24 is subnetted, 1 subnets
S 172.16.10.0 [150/0] via 10.1.3.1
C 192.168.10.0/24 is directly connected, FastEthernet0/0
C 192.168.20.0/24 is directly connected, FastEthernet0/1
S 192.168.30.0/24 [150/0] via 10.1.3.1
S 192.168.40.0/24 [150/0] via 10.1.2.1
These RIP routes are being advertised as available *to other RIP routers*.
CORP is advertisting THREE routes via RIP to R1 right now
10.1.1.0
10.1.4.0
10.1.5.0
access to those networks can be achieved by R1 by going THROUGH CORP via ingress .2.1 or .3.1
The advantage..... is that we didnt statically program these routes
we engaged RIP, on BOTH routers- R1 and Corp, and handed them BOTH the network "10.0.0.0"
So, why did RIP choose to display these particular routes
Keep in mind that the output above is from R1 only... In the context of the R1 ROUTER ONLY,
there are three relevant routes within the "10.0.0.0" parameter we specified. The three routes involve Corp.
Corp is sending RIP data about these routes to Corp.
Lets look closer at how this is happening:
here's our starting point before any RIP is set
here's our routing tables after i set RIP with 10.0.0.0 on both..
FIRST i set it on Corp, then R1.(per the book's instructions) As a result we are seeing RIP routes in R1 only....
then I went back to a fresh packet tracer file with no RIP set. And I set RIP in the opposite order;
FIRST i set it on R1, then Corp. And again, we are seeing RIP routes in R1 only....
I wanted to prove that it didnt matter which order we enabled RIP on the two routers. What matters here is that
we enable RIP on both of them with the criteria of 10.0.0.0
Recall the topology:
if Corp and R1 are set for RIP and given the criteria 10.0.0.0, meaning that we are trying to reach networks
within that range, then it follows that Corp will advertise 1.1.0, 1.4.0, and 1.5.0 to R1, because Corp stands between those networks
and R1
"Hi R1, I'm Corp I have three networks that fall inside 10.0.0.0, and you can reach them through me via .2.1 or .3.1"
It also follows that Corp's routing table shows no RIP routes- because R1 isnt advertising any. R1 doesnt have any networks
in the 10.0.0.0 range that Corp could reach
To further clarify this, we'll proceed with the book's instructions. We'll now set more RIP routes on R1
R1(config)#
router rip
R1(config-router)#
network 192.168.10.0
R1(config-router)#
network 192.168.20.0
Corp routing table before RIP set on R1:
Corp#
show ip route
10.0.0.0/8 is variably subnetted, 10 subnets, 2 masks
C 10.1.1.0/24 is directly connected, Vlan1
L 10.1.1.1/32 is directly connected, Vlan1
C 10.1.2.0/24 is directly connected, Serial0/0/0
L 10.1.2.1/32 is directly connected, Serial0/0/0
C 10.1.3.0/24 is directly connected, Serial0/0/1
L 10.1.3.1/32 is directly connected, Serial0/0/1
C 10.1.4.0/24 is directly connected, Serial0/1/0
L 10.1.4.1/32 is directly connected, Serial0/1/0
C 10.1.5.0/24 is directly connected, FastEthernet0/0
L 10.1.5.1/32 is directly connected, FastEthernet0/0
172.16.0.0/24 is subnetted, 1 subnets
S 172.16.10.0/24 [150/0] via 10.1.5.2
S 192.168.10.0/24 [150/0] via 10.1.2.2
S 192.168.20.0/24 [150/0] via 10.1.3.2
S 192.168.30.0/24 [150/0] via 10.1.4.2
S 192.168.40.0/24 [150/0] via 10.1.4.2
Corp routing table after RIP set on R1:
Gateway of last resort is not set
10.0.0.0/8 is variably subnetted, 10 subnets, 2 masks
C 10.1.1.0/24 is directly connected, Vlan1
L 10.1.1.1/32 is directly connected, Vlan1
C 10.1.2.0/24 is directly connected, Serial0/0/0
L 10.1.2.1/32 is directly connected, Serial0/0/0
C 10.1.3.0/24 is directly connected, Serial0/0/1
L 10.1.3.1/32 is directly connected, Serial0/0/1
C 10.1.4.0/24 is directly connected, Serial0/1/0
L 10.1.4.1/32 is directly connected, Serial0/1/0
C 10.1.5.0/24 is directly connected, FastEthernet0/0
L 10.1.5.1/32 is directly connected, FastEthernet0/0
nothing changed so far
172.16.0.0/24 is subnetted, 1 subnets
S 172.16.10.0/24 [150/0] via 10.1.5.2
no change
R 192.168.10.0/24 [120/1] via 10.1.2.2, 00:00:08, Serial0/0/0
[120/1] via 10.1.3.2, 00:00:08, Serial0/0/1
RIP overrides static- 2 paths available now
R 192.168.20.0/24 [120/1] via 10.1.2.2, 00:00:08, Serial0/0/0
[120/1] via 10.1.3.2, 00:00:08, Serial0/0/1
RIP overrides static- 2 paths available now
S 192.168.30.0/24 [150/0] via 10.1.4.2
no change
S 192.168.40.0/24 [150/0] via 10.1.4.2
no change
"Hi Corp- I'm R1 and I have zero networks
that fall inside 10.0.0.0, however I do have some networks that fall within
192.168.20.0 and 192.168.10.0
and you can reach them through me(R1) if you ingress at .1.2.2 or .1.3.2"
ok, we have the concept down. Time to proceed and set up RIP on R2............
R2(config)#
router rip
R2(config-router)#
network 10.0.0.0
R2(config-router)#
network 192.168.30.0
R2(config-router)#
network 192.168.40.0
R2 before RIP enabled
R2#
show ip route
10.0.0.0/24 is subnetted, 5 subnets
S 10.1.1.0 [150/0] via 10.1.4.1
S 10.1.2.0 [150/0] via 10.1.4.1
S 10.1.3.0 [150/0] via 10.1.4.1
C 10.1.4.0 is directly connected, Serial0/0/0
S 10.1.5.0 [150/0] via 10.1.4.1
172.16.0.0/24 is subnetted, 1 subnets
S 172.16.10.0 [150/0] via 10.1.4.1
S 192.168.10.0/24 [150/0] via 10.1.4.1
S 192.168.20.0/24 [150/0] via 10.1.4.1
C 192.168.30.0/24 is directly connected, FastEthernet0/0
C 192.168.40.0/24 is directly connected, FastEthernet0/1
R2 after RIP added
R2#
show ip route
10.0.0.0/24 is subnetted, 5 subnets
R 10.1.1.0 [120/1] via 10.1.4.1, 00:00:24, Serial0/0/0
from corp
R 10.1.2.0 [120/1] via 10.1.4.1, 00:00:24, Serial0/0/0
from corp
R 10.1.3.0 [120/1] via 10.1.4.1, 00:00:24, Serial0/0/0
from corp
C 10.1.4.0 is directly connected, Serial0/0/0
R 10.1.5.0 [120/1] via 10.1.4.1, 00:00:24, Serial0/0/0
from corp
172.16.0.0/24 is subnetted, 1 subnets
S 172.16.10.0 [150/0] via 10.1.4.1
R 192.168.10.0/24 [120/2] via 10.1.4.1, 00:00:24, Serial0/0/0
from R1 via corp
R 192.168.20.0/24 [120/2] via 10.1.4.1, 00:00:24, Serial0/0/0
from R1 via corp
C 192.168.30.0/24 is directly connected, FastEthernet0/0
C 192.168.40.0/24 is directly connected, FastEthernet0/1
now lets compare the Corp and R1 routing tables- before RIP was set on R2 and after
Corp before R2 RIP
Corp#
show ip route
10.0.0.0/8 is variably subnetted, 10 subnets, 2 masks
C 10.1.1.0/24 is directly connected, Vlan1
L 10.1.1.1/32 is directly connected, Vlan1
C 10.1.2.0/24 is directly connected, Serial0/0/0
L 10.1.2.1/32 is directly connected, Serial0/0/0
C 10.1.3.0/24 is directly connected, Serial0/0/1
L 10.1.3.1/32 is directly connected, Serial0/0/1
C 10.1.4.0/24 is directly connected, Serial0/1/0
L 10.1.4.1/32 is directly connected, Serial0/1/0
C 10.1.5.0/24 is directly connected, FastEthernet0/0
L 10.1.5.1/32 is directly connected, FastEthernet0/0
172.16.0.0/24 is subnetted, 1 subnets
S 172.16.10.0/24 [150/0] via 10.1.5.2
R 192.168.10.0/24 [120/1] via 10.1.2.2, 00:00:02, Serial0/0/0
[120/1] via 10.1.3.2, 00:00:02, Serial0/0/1
R 192.168.20.0/24 [120/1] via 10.1.2.2, 00:00:02, Serial0/0/0
[120/1] via 10.1.3.2, 00:00:02, Serial0/0/1
from R1
S 192.168.30.0/24 [150/0] via 10.1.4.2
S 192.168.40.0/24 [150/0] via 10.1.4.2
Corp after R2 RIP
Corp#
show ip route
10.0.0.0/8 is variably subnetted, 10 subnets, 2 masks
C 10.1.1.0/24 is directly connected, Vlan1
L 10.1.1.1/32 is directly connected, Vlan1
C 10.1.2.0/24 is directly connected, Serial0/0/0
L 10.1.2.1/32 is directly connected, Serial0/0/0
C 10.1.3.0/24 is directly connected, Serial0/0/1
L 10.1.3.1/32 is directly connected, Serial0/0/1
C 10.1.4.0/24 is directly connected, Serial0/1/0
L 10.1.4.1/32 is directly connected, Serial0/1/0
C 10.1.5.0/24 is directly connected, FastEthernet0/0
L 10.1.5.1/32 is directly connected, FastEthernet0/0
172.16.0.0/24 is subnetted, 1 subnets
S 172.16.10.0/24 [150/0] via 10.1.5.2
R 192.168.10.0/24 [120/1] via 10.1.2.2, 00:00:19, Serial0/0/0
[120/1] via 10.1.3.2, 00:00:19, Serial0/0/1
R 192.168.20.0/24 [120/1] via 10.1.2.2, 00:00:19, Serial0/0/0
[120/1] via 10.1.3.2, 00:00:19, Serial0/0/1
from R1
R 192.168.30.0/24 [120/1] via 10.1.4.2, 00:00:15, Serial0/1/0
R 192.168.40.0/24 [120/1] via 10.1.4.2, 00:00:15, Serial0/1/0
from R2
RIP on R2 is advertising .30.0 and .40.0 to Corp
R1 before R2 RIP
R1#
show ip route
10.0.0.0/24 is subnetted, 5 subnets
R 10.1.1.0 [120/1] via 10.1.2.1, 00:00:05, Serial0/0/0
[120/1] via 10.1.3.1, 00:00:05, Serial0/0/1
from Corp
C 10.1.2.0 is directly connected, Serial0/0/0
C 10.1.3.0 is directly connected, Serial0/0/1
R 10.1.4.0 [120/1] via 10.1.2.1, 00:00:05, Serial0/0/0
[120/1] via 10.1.3.1, 00:00:05, Serial0/0/1
R 10.1.5.0 [120/1] via 10.1.2.1, 00:00:05, Serial0/0/0
[120/1] via 10.1.3.1, 00:00:05, Serial0/0/1
from Corp
172.16.0.0/24 is subnetted, 1 subnets
S 172.16.10.0 [150/0] via 10.1.3.1
C 192.168.10.0/24 is directly connected, FastEthernet0/0
C 192.168.20.0/24 is directly connected, FastEthernet0/1
S 192.168.30.0/24 [150/0] via 10.1.3.1
S 192.168.40.0/24 [150/0] via 10.1.2.1
R1 after R2 RIP
R1#
show ip route
10.0.0.0/24 is subnetted, 5 subnets
R 10.1.1.0 [120/1] via 10.1.2.1, 00:00:06, Serial0/0/0
[120/1] via 10.1.3.1, 00:00:06, Serial0/0/1
from Corp
C 10.1.2.0 is directly connected, Serial0/0/0
C 10.1.3.0 is directly connected, Serial0/0/1
R 10.1.4.0 [120/1] via 10.1.2.1, 00:00:06, Serial0/0/0
[120/1] via 10.1.3.1, 00:00:06, Serial0/0/1
R 10.1.5.0 [120/1] via 10.1.2.1, 00:00:06, Serial0/0/0
[120/1] via 10.1.3.1, 00:00:06, Serial0/0/1
from Corp
172.16.0.0/24 is subnetted, 1 subnets
S 172.16.10.0 [150/0] via 10.1.3.1
C 192.168.10.0/24 is directly connected, FastEthernet0/0
C 192.168.20.0/24 is directly connected, FastEthernet0/1
R 192.168.30.0/24 [120/2] via 10.1.3.1, 00:00:06, Serial0/0/1
[120/2] via 10.1.2.1, 00:00:06, Serial0/0/0
R 192.168.40.0/24 [120/2] via 10.1.2.1, 00:00:06, Serial0/0/0
[120/2] via 10.1.3.1, 00:00:06, Serial0/0/1
from R2 via Corp
Now to set RIP on R3
R3(config)#
router rip
R3(config-router)#
network 10.0.0.0
R3(config-router)#
network 172.16.0.0
note that R3 is our only router with "gateway of last resort" set because we set a default route instead of static routes
As a result, we only see directly connected routes listed, along with a single "S*" for the default gateway
R3 before RIP
R3#
show ip route
Gateway of last resort is 10.1.5.1 to network 0.0.0.0
10.0.0.0/8 is variably subnetted, 2 subnets, 2 masks
C 10.1.5.0/24 is directly connected, FastEthernet0/0
L 10.1.5.2/32 is directly connected, FastEthernet0/0
172.16.0.0/16 is variably subnetted, 2 subnets, 2 masks
C 172.16.10.0/24 is directly connected, Dot11Radio0/0/0
L 172.16.10.1/32 is directly connected, Dot11Radio0/0/0
S* 0.0.0.0/0 [1/0] via 10.1.5.1
R3 after RIP
R3#
show ip route
Gateway of last resort is 10.1.5.1 to network 0.0.0.0
-------------------------------------------------------------
10.0.0.0/8 is variably subnetted, 6 subnets, 2 masks
R 10.1.1.0/24 [120/1] via 10.1.5.1, 00:00:21, FastEthernet0/0
R 10.1.2.0/24 [120/1] via 10.1.5.1, 00:00:21, FastEthernet0/0
R 10.1.3.0/24 [120/1] via 10.1.5.1, 00:00:21, FastEthernet0/0
R 10.1.4.0/24 [120/1] via 10.1.5.1, 00:00:21, FastEthernet0/0
from Corp
C 10.1.5.0/24 is directly connected, FastEthernet0/0
L 10.1.5.2/32 is directly connected, FastEthernet0/0
-------------------------------------------------------------
172.16.0.0/16 is variably subnetted, 2 subnets, 2 masks
C 172.16.10.0/24 is directly connected, Dot11Radio0/0/0
L 172.16.10.1/32 is directly connected, Dot11Radio0/0/0
R 192.168.10.0/24 [120/2] via 10.1.5.1, 00:00:21, FastEthernet0/0
R 192.168.20.0/24 [120/2] via 10.1.5.1, 00:00:21, FastEthernet0/0
From R1 via Corp
R 192.168.30.0/24 [120/2] via 10.1.5.1, 00:00:21, FastEthernet0/0
R 192.168.40.0/24 [120/2] via 10.1.5.1, 00:00:21, FastEthernet0/0
From R2 via Corp
S* 0.0.0.0/0 [1/0] via 10.1.5.1
Corp before R3 RIP
Corp#
show ip route
10.0.0.0/8 is variably subnetted, 10 subnets, 2 masks
C 10.1.1.0/24 is directly connected, Vlan1
L 10.1.1.1/32 is directly connected, Vlan1
C 10.1.2.0/24 is directly connected, Serial0/0/0
L 10.1.2.1/32 is directly connected, Serial0/0/0
C 10.1.3.0/24 is directly connected, Serial0/0/1
L 10.1.3.1/32 is directly connected, Serial0/0/1
C 10.1.4.0/24 is directly connected, Serial0/1/0
L 10.1.4.1/32 is directly connected, Serial0/1/0
C 10.1.5.0/24 is directly connected, FastEthernet0/0
L 10.1.5.1/32 is directly connected, FastEthernet0/0
172.16.0.0/24 is subnetted, 1 subnets
S 172.16.10.0/24 [150/0] via 10.1.5.2
R 192.168.10.0/24 [120/1] via 10.1.2.2, 00:00:26, Serial0/0/0
[120/1] via 10.1.3.2, 00:00:26, Serial0/0/1
R 192.168.20.0/24 [120/1] via 10.1.2.2, 00:00:26, Serial0/0/0
[120/1] via 10.1.3.2, 00:00:26, Serial0/0/1
from R1 via corp
R 192.168.30.0/24 [120/1] via 10.1.4.2, 00:00:21, Serial0/1/0
R 192.168.40.0/24 [120/1] via 10.1.4.2, 00:00:21, Serial0/1/0
from R2 via corp
Corp after R3 RIP
Corp#
show ip route
10.0.0.0/8 is variably subnetted, 10 subnets, 2 masks
C 10.1.1.0/24 is directly connected, Vlan1
L 10.1.1.1/32 is directly connected, Vlan1
C 10.1.2.0/24 is directly connected, Serial0/0/0
L 10.1.2.1/32 is directly connected, Serial0/0/0
C 10.1.3.0/24 is directly connected, Serial0/0/1
L 10.1.3.1/32 is directly connected, Serial0/0/1
C 10.1.4.0/24 is directly connected, Serial0/1/0
L 10.1.4.1/32 is directly connected, Serial0/1/0
C 10.1.5.0/24 is directly connected, FastEthernet0/0
L 10.1.5.1/32 is directly connected, FastEthernet0/0
172.16.0.0/16 is variably subnetted, 2 subnets, 2 masks
R 172.16.0.0/16 [120/1] via 10.1.5.2, 00:00:13, FastEthernet0/0
S 172.16.10.0/24 [150/0] via 10.1.5.2
from R3
R 192.168.10.0/24 [120/1] via 10.1.3.2, 00:00:13, Serial0/0/1
[120/1] via 10.1.2.2, 00:00:13, Serial0/0/0
R 192.168.20.0/24 [120/1] via 10.1.3.2, 00:00:13, Serial0/0/1
[120/1] via 10.1.2.2, 00:00:13, Serial0/0/0
from R1 via corp
R 192.168.30.0/24 [120/1] via 10.1.4.2, 00:00:24, Serial0/1/0
R 192.168.40.0/24 [120/1] via 10.1.4.2, 00:00:24, Serial0/1/0
from R2 via corp
R2 before R3 RIP
R2#
show ip route
10.0.0.0/24 is subnetted, 5 subnets
R 10.1.1.0 [120/1] via 10.1.4.1, 00:00:15, Serial0/0/0
R 10.1.2.0 [120/1] via 10.1.4.1, 00:00:15, Serial0/0/0
R 10.1.3.0 [120/1] via 10.1.4.1, 00:00:15, Serial0/0/0
from Corp
C 10.1.4.0 is directly connected, Serial0/0/0
R 10.1.5.0 [120/1] via 10.1.4.1, 00:00:15, Serial0/0/0
from Corp
172.16.0.0/24 is subnetted, 1 subnets
S 172.16.10.0 [150/0] via 10.1.4.1
R 192.168.10.0/24 [120/2] via 10.1.4.1, 00:00:15, Serial0/0/0
R 192.168.20.0/24 [120/2] via 10.1.4.1, 00:00:15, Serial0/0/0
from R1 via Corp
C 192.168.30.0/24 is directly connected, FastEthernet0/0
C 192.168.40.0/24 is directly connected, FastEthernet0/1
R2 after R3 RIP
R2#
show ip route
10.0.0.0/24 is subnetted, 5 subnets
R 10.1.1.0 [120/1] via 10.1.4.1, 00:00:20, Serial0/0/0
R 10.1.2.0 [120/1] via 10.1.4.1, 00:00:20, Serial0/0/0
R 10.1.3.0 [120/1] via 10.1.4.1, 00:00:20, Serial0/0/0
from Corp
C 10.1.4.0 is directly connected, Serial0/0/0
R 10.1.5.0 [120/1] via 10.1.4.1, 00:00:20, Serial0/0/0
from Corp
172.16.0.0/16 is variably subnetted, 2 subnets, 2 masks
R 172.16.0.0/16 [120/2] via 10.1.4.1, 00:00:20, Serial0/0/0
S 172.16.10.0/24 [150/0] via 10.1.4.1
from R3 via Corp
R 192.168.10.0/24 [120/2] via 10.1.4.1, 00:00:20, Serial0/0/0
R 192.168.20.0/24 [120/2] via 10.1.4.1, 00:00:20, Serial0/0/0
from R1 via Corp
C 192.168.30.0/24 is directly connected, FastEthernet0/0
C 192.168.40.0/24 is directly connected, FastEthernet0/1
R1 before R3 RIP
R1#
show ip route
10.0.0.0/24 is subnetted, 5 subnets
R 10.1.1.0 [120/1] via 10.1.2.1, 00:00:04, Serial0/0/0
[120/1] via 10.1.3.1, 00:00:04, Serial0/0/1
C 10.1.2.0 is directly connected, Serial0/0/0
C 10.1.3.0 is directly connected, Serial0/0/1
R 10.1.4.0 [120/1] via 10.1.2.1, 00:00:04, Serial0/0/0
[120/1] via 10.1.3.1, 00:00:04, Serial0/0/1
R 10.1.5.0 [120/1] via 10.1.2.1, 00:00:04, Serial0/0/0
[120/1] via 10.1.3.1, 00:00:04, Serial0/0/1
from Corp
172.16.0.0/24 is subnetted, 1 subnets
S 172.16.10.0 [150/0] via 10.1.3.1
C 192.168.10.0/24 is directly connected, FastEthernet0/0
C 192.168.20.0/24 is directly connected, FastEthernet0/1
R 192.168.30.0/24 [120/2] via 10.1.2.1, 00:00:04, Serial0/0/0
[120/2] via 10.1.3.1, 00:00:04, Serial0/0/1
R 192.168.40.0/24 [120/2] via 10.1.2.1, 00:00:04, Serial0/0/0
[120/2] via 10.1.3.1, 00:00:04, Serial0/0/1
from R2 via Corp
R1 after R3 RIP
R1#
show ip route
10.0.0.0/24 is subnetted, 5 subnets
R 10.1.1.0 [120/1] via 10.1.3.1, 00:00:03, Serial0/0/1
[120/1] via 10.1.2.1, 00:00:03, Serial0/0/0
C 10.1.2.0 is directly connected, Serial0/0/0
C 10.1.3.0 is directly connected, Serial0/0/1
R 10.1.4.0 [120/1] via 10.1.3.1, 00:00:03, Serial0/0/1
[120/1] via 10.1.2.1, 00:00:03, Serial0/0/0
R 10.1.5.0 [120/1] via 10.1.3.1, 00:00:03, Serial0/0/1
[120/1] via 10.1.2.1, 00:00:03, Serial0/0/0
from Corp
172.16.0.0/16 is variably subnetted, 2 subnets, 2 masks
R 172.16.0.0/16 [120/2] via 10.1.3.1, 00:00:03, Serial0/0/1
[120/2] via 10.1.2.1, 00:00:03, Serial0/0/0
S 172.16.10.0/24 [150/0] via 10.1.3.1
from R3 via Corp
C 192.168.10.0/24 is directly connected, FastEthernet0/0
C 192.168.20.0/24 is directly connected, FastEthernet0/1
R 192.168.30.0/24 [120/2] via 10.1.3.1, 00:00:03, Serial0/0/1
[120/2] via 10.1.2.1, 00:00:03, Serial0/0/0
R 192.168.40.0/24 [120/2] via 10.1.3.1, 00:00:03, Serial0/0/1
[120/2] via 10.1.2.1, 00:00:03, Serial0/0/0
from R2 via Corp
Verifying Configurations
in addition to
show ip route
we can also use
show ip protocols
and
debug rip ip
Corp#
show ip protocols
Routing Protocol is "rip"
Sending updates every 30 seconds, next due in 11 seconds
Invalid after 180 seconds, hold down 180, flushed after 240
Outgoing update filter list for all interfaces is not set
Incoming update filter list for all interfaces is not set
Redistributing: rip
Default version control: send version 1, receive any version
Interface Send Recv Triggered RIP Key-chain
Vlan1 1 2 1
FastEthernet0/0 1 2 1
Serial0/0/1 1 2 1
Serial0/1/0 1 2 1
Serial0/0/0 1 2 1
Automatic network summarization is in effect
Maximum path: 4
Routing for Networks:
10.0.0.0
Passive Interface(s):
Routing Information Sources:
Gateway Distance Last Update
10.1.5.2 120 00:00:00
10.1.3.2 120 00:00:10
10.1.2.2 120 00:00:10
10.1.4.2 120 00:00:20
Distance: (default is 120)
R3#
debug ip rip
R3#RIP: received v1 update from 10.1.5.1 on FastEthernet0/0
10.1.1.0 in 1 hops
10.1.2.0 in 1 hops
10.1.3.0 in 1 hops
10.1.4.0 in 1 hops
192.168.10.0 in 2 hops
192.168.20.0 in 2 hops
192.168.30.0 in 2 hops
192.168.40.0 in 2 hops
R3#RIP: sending v1 update to 255.255.255.255 via Dot11Radio0/0/0 (172.16.10.1)
RIP: build update entries
network 10.0.0.0 metric 1
network 192.168.10.0 metric 3
network 192.168.20.0 metric 3
network 192.168.30.0 metric 3
network 192.168.40.0 metric 3
RIP: sending v1 update to 255.255.255.255 via FastEthernet0/0 (10.1.5.2)
RIP: build update entries
network 172.16.0.0 metric 1
output loops until manually disabled..............
R3#
undebug all
All possible debugging has been turned off
Note that due to the Split Horizon rule, R3 is not sending all of it's known RIP data to Corp.
It is sending all known RIP data out of the wifi interface (even there though there's no router that way),
but it is ONLY sending data about the wifi network back to Corp; data that Corp doesnt already have
Now lets look at some examples with sample routers..
I got hung up on these two examples because I found the
wording to be a bit confusing. Also there was subnetting involved that I was able to figure out, but threw me at first
First source of confusion- we have two seperate examples, and I was mixing them up.
The examples are:
Use the debug ip rip command to both:
discover a problem
and figure out how RIP was configured on a router from a different sample network
The conclusion regarding 'figuring out how RIP is configured' on this router, is that RIP networks are set as 10.0.0.0 and 172.16.0.0.
We determined that we are not the 'first source' of info on the 192.168.1.0 nertwork, since it is a metric of 2. We are sending out RIP data on that network,
but that RIP data is made availbale to us via another router.
I also got tripped up on the fact that RA is sending out S0/0 which corresponds 10.0.8.1,
and then receiving on the same interface S0/0 from an ip address of 10.0.15.0 on the other side of the link
I was able to determine that these two address are actually on the same subnet. My initial assumption was that the network address for the link is 10.0.0.0.
The problem doesn't give the subnet mask- I guessed it as /20 by using a 16 block since we can see that the third octet seems to move in 8's
if the network starts at 10.0.0.0 and we use /20 with 16 block, we would indeed have a last host address of 10.0.15.254, so 10.0.15.2 would be a valid host.
So there was a twist to this problem which needed subnetting to solve. It wasnt particulary releveant to the subject of RIP, but I was curious why the address on
the other side of that link looked so strange.
The problem also points out that we can determine there are 'at least' two routers participating in RIP here since we are sending RIP data out two interfaces but
only receiving RIP data on one interface. I'm unclear on why its worded this way; we know we are a RIP router- the fact that we are receiving data on one interface
would suggest there is 'at least one more' RIP router out there.
that's it for this example. Back to the original statement-
Use the debug ip rip command to both discover a problem and figure out
how RIP was configured on a router from a different sample network
We just 'figured out how RIP was configured on a router'.. The second example is regarding 'discovering a problem', although it is mentioned first.
The second example will use debug ip rip and show ip route to find a problem with the network
it looks like RIP data for 172.16.20.0 was received on S0/0, and then that interface was bumped out of the routing table entry for that network in favor of a static route.
ok, moving on now to RIP V2
RIP V2
enable it on all four routers
Corp(config)
router rip
Corp(config-router)
version 2
R1(config)
router rip
R1(config-router)
version 2
R2(config)
router rip
R2(config-router)
version 2
R3(config)
router rip
R3(config-router)
version 2
We'll use R1 to compare RIPv1 and RIPv2
RIPv1
R1(config)
debug ip rip
R1#RIP: sending v1 update to 255.255.255.255 via FastEthernet0/0 (192.168.10.1)
RIP: build update entries
network 10.0.0.0 metric 1
network 172.16.0.0 metric 3
network 192.168.20.0 metric 1
network 192.168.30.0 metric 3
network 192.168.40.0 metric 3
RIP: sending v1 update to 255.255.255.255 via FastEthernet0/1 (192.168.20.1)
RIP: build update entries
network 10.0.0.0 metric 1
network 172.16.0.0 metric 3
network 192.168.10.0 metric 1
network 192.168.30.0 metric 3
network 192.168.40.0 metric 3
RIP: sending v1 update to 255.255.255.255 via Serial0/0/0 (10.1.2.2)
RIP: build update entries
network 10.1.3.0 metric 1
network 192.168.10.0 metric 1
network 192.168.20.0 metric 1
RIP: sending v1 update to 255.255.255.255 via Serial0/0/1 (10.1.3.2)
RIP: build update entries
network 10.1.2.0 metric 1
network 192.168.10.0 metric 1
network 192.168.20.0 metric 1
RIPv2
R1(config)
debug ip rip
R1#RIP: sending v2 update to 224.0.0.9 via FastEthernet0/0 (192.168.10.1)
RIP: build update entries
10.0.0.0/8 via 0.0.0.0, metric 1, tag 0
172.16.0.0/16 via 0.0.0.0, metric 3, tag 0
192.168.20.0/24 via 0.0.0.0, metric 1, tag 0
192.168.30.0/24 via 0.0.0.0, metric 3, tag 0
192.168.40.0/24 via 0.0.0.0, metric 3, tag 0
RIP: sending v2 update to 224.0.0.9 via FastEthernet0/1 (192.168.20.1)
RIP: build update entries
10.0.0.0/8 via 0.0.0.0, metric 1, tag 0
172.16.0.0/16 via 0.0.0.0, metric 3, tag 0
192.168.10.0/24 via 0.0.0.0, metric 1, tag 0
192.168.30.0/24 via 0.0.0.0, metric 3, tag 0
192.168.40.0/24 via 0.0.0.0, metric 3, tag 0
RIP: sending v2 update to 224.0.0.9 via Serial0/0/0 (10.1.2.2)
RIP: build update entries
10.1.3.0/24 via 0.0.0.0, metric 1, tag 0
192.168.10.0/24 via 0.0.0.0, metric 1, tag 0
192.168.20.0/24 via 0.0.0.0, metric 1, tag 0
RIP: sending v2 update to 224.0.0.9 via Serial0/0/1 (10.1.3.2)
RIP: build update entries
10.1.2.0/24 via 0.0.0.0, metric 1, tag 0
192.168.10.0/24 via 0.0.0.0, metric 1, tag 0
192.168.20.0/24 via 0.0.0.0, metric 1, tag 0
R1(config)
show ip protocols
Routing Protocol is "rip"
Sending updates every 30 seconds, next due in 13 seconds
Invalid after 180 seconds, hold down 180, flushed after 240
Outgoing update filter list for all interfaces is not set
Incoming update filter list for all interfaces is not set
Redistributing: rip
Default version control: send version 2, receive 2
Interface Send Recv Triggered RIP Key-chain
FastEthernet0/0 2 2
FastEthernet0/1 2 2
Serial0/0/0 2 2
Serial0/0/1 2 2
Automatic network summarization is in effect
Maximum path: 4
Routing for Networks:
10.0.0.0
192.168.10.0
192.168.20.0
Passive Interface(s):
Routing Information Sources:
Gateway Distance Last Update
10.1.3.1 120 00:00:21
10.1.2.1 120 00:00:21
Distance: (default is 120)
final task of this chapter
Enable a default route out to the internet , and advertise via RIP
R3(config)#
interface s0/1/0 (this is only for example, so I am not adding a serial card to R3)
R3(config-if)#
ip addr 172.16.10.5 255.255.255.252
R3(config-if)#
exit
R3(config)#
ip route 0.0.0.0 0.0.0.0 s0/0
R3(config)#
ip default-network 172.16.0.0 tells other routers via RIP that default WAN route is through R3
Chapter 8 Exam Essentials IP Routing
1. Describe the Basic IP routing process
frame changes at each hop, but packet doesnt change EXCEPT that the TTL field in the IP header decrements
2. List the information required by a router to successfully route packets
destination IP address, location of other routers, possible routers to all remote networks,
the best route to each network, how to maintain and maintain routing info
3. Describe how MAC addresses are used during the routing process
a MAC will never pass a router interface. MACs will change between router interfaces
4. View and interpret the routing table of a router
use show ip route to see the table
a "C" indicates directly connected, an "R" indicates RIP provided the route info, "S" means static
5. differentiate the three types of routing
static- manually configured
dynamic- routers automatically share info via protocol
default- a special route is configured for all traffic without a more specific destination network found in the table
6. Compare and contrast static and dynamic routing
static routing creates no routing update traffic which means less overhead on the routers and links- but it must be
configured manually and can't react if links are lost.
dynamic routing creates update traffic, but it can react to outages and choose the best route when multiple routes exist to the same network
7. Configure static routes at the CLI
route [dest network] [mask] [next hop address OR exit interface] [admin distance] [permanent]
Ex:
Corp(config)#
ip route 192.168.10.0 255.255.255.0 10.1.2.2 150
8. Create a default route
ip route 0.0.0.0 0.0.0.0 [ip address OR exit interface]
Ex:
R3(config)#
ip route 0.0.0.0 0.0.0.0 10.1.5.1 (ingress at Corp router- use if R3 cant identify route)
9. Understand administrative distance and its role in the selection of the best route
an integer from 0 (most trusted) to 255 (no traffic will pass via this route).
All routing protocols are assigned an AD but it can be changed at the CLI
10. Differentiate distance-vector, link-state, and hybrid routing protocols
distance vector- based on hop count (RIP)
link-state- multiple factors such as bandwidth and delay
hybrid- uses both
11. List mechanisms used to prevent routing loops in the network
max hop count, split horizon, route poisoning, holddown counters
12. Describe the counts used the operation of RIP
route update timer- (30) interval between routing updates
route invalid timer- (180, update x 3) before a route is determined invalid
holddown timer-(180) time info is supressed when a link is lost
route flush timer- (240) seconds before invalid and removal
13. Configure RIP routing
router rip
network x.x.x.x
the network(s) you want to advertise from your router. It only works if the other router has RIP enabled.
By enabling RIP, you are able to RECEIVE RIP data from other RIP routers.
by specifying a network, you are SENDING RIP data on that network
14. Identify commands used to verify RIP routing
show ip route will provide contents of the routing table with codes (R, C, S)
debug ip rip will show RIP updates being sent and received
15. Describe the differences between RIPv1 and RIPv2
RIPv1 sends a broadcast (255.255.255.255) every 30 seconds and has an AD of 120.
RIPv1 is classful only, does not send any mask info. No authentication between routers.
RIPv2 sends multicasts (224.0.0.9) every 30 seconds and sends mask info, which allows it to support classless networking, RIPv2 also supports
autentication between routers.
Chapter 8 Written Lab 8.0
1. At the appropriate prompt, create a static route to network 172.16.10.0/24 with a next-hop
gateway of 172.16.20.1 and an administrative distance of 150.
Router(config)#
ip route 172.16.10.0 255.255.255.0 172.16.20.1 150
2. When a PC sends a packet to another PC in a remote network, what destination IP address and MAC address will
be in the frame that it sends to it's default gateway?
the gateway interface MAC and the remote PC's IP
3. At the appropriate prompt, create a default route to 172.16.40.1
Router(config)#
ip route 0.0.0.0 0.0.0.0 172.16.40.1
"to" is the wrong word.. we are going TO any route VIA 172.16.40.1
4. If you are using default routing in a classless environment, what command must also be used?
Router(config)#
ip classless
5. On which type of network is a default route most beneficial?
stub
6. At the appropriate prompt, display the routing table on your router
Router#
show ip route
7. When creating a static or default route, you dont have to use the next-hop ip address;
you can instead use the ____________
exit interface
8. True/False: To reach a destination host, you must know the MAC address of the remote host
false, you need the MAC of your router
9. True/False: To reach a destination host, you must know the IP address of the remote host
true
10. At the appropriate prompt, execute the command required on a DCE serial interface that is not required
on a DTE serial interface
Router(config-if)#
clock rate X
11. At the appropriate prompt, enable RIP routing on the interface with the IP address 10.0.0.1/24
Router(config)#
router rip
Router(config-router)#
network 10.0.0.0
RIPv1 is CLASSFUL only... use the classful mask based on the first octet given
12. At the appropriate prompt, prevent a router from propagating IP information out serial 1
Router(config)#
router rip
Router(config-router)#
passive-interface S0/1
can receive RIP data but will not send
13. What routing loop prevention mechanism sends out a maximum hop count as soon as a link fails?
route poisoning
14. What routing loop prevention mechanism suppresses the resending of routing information to an interface
through which it was received?
split horizon
15. At the appropriate prompt display RIP routing updates as they are sent and received on the router
to the console session
Router#
debug ip rip
to turn it off:
Router#
undebug all
Chapter 8 Hands-on Labs
For these labs we will need a network with three routers.
Lab 8.1 Creating Static routes
first set the interfaces, then program the static routes
LabA(config)#
int s0/0/0
LabA(config-if)#
ip addr 172.16.20.1
LabA(config-if)#
int f0/0
LabA(config-if)#
ip addr 172.16.10.1
-----------------------------------------------------------------
LabA(config)#
ip route 172.16.30.0 255.255.255.0 172.16.20.2
LabA(config)#
ip route 172.16.40.0 255.255.255.0 172.16.20.2
LabB(config)#
int s0/0/0
LabB(config-if)#
ip addr 172.16.20.2
LabB(config-if)#
int s0/0/1
LabB(config-if)#
ip addr 172.16.30.1
-----------------------------------------------------------------
LabB(config)#
ip route 172.16.10.0 255.255.255.0 172.16.20.1
LabB(config)#
ip route 172.16.40.0 255.255.255.0 172.16.30.2
LabC(config)#
int s0/0/0
LabC(config-if)#
ip addr 172.16.30.2
LabC(config-if)#
int f0/0
LabC(config-if)#
ip addr 172.16.40.1
-----------------------------------------------------------------
LabC(config)#
ip route 172.16.10.0 255.255.255.0 172.16.30.1
LabC(config)#
ip route 172.16.20.0 255.255.255.0 172.16.30.1
Lab 8.2 RIP Configuration
remove the static routes, enable and configure RIP with the classful network id that covers the routes you want to advertise
LabA(config)#
no ip route 172.16.30.0 255.255.255.0 172.16.20.2
LabA(config)#
no ip route 172.16.40.0 255.255.255.0 172.16.20.2
LabA(config)#
router rip
LabA(config-router)#
network 172.16.0.0
LabA(config-router)#
do show ip route
Gateway of last resort is not set
172.16.0.0/16 is variably subnetted, 5 subnets, 2 masks
C 172.16.10.0/24 is directly connected, FastEthernet0/0
L 172.16.10.1/32 is directly connected, FastEthernet0/0
C 172.16.20.0/24 is directly connected, Serial0/0/0
L 172.16.20.1/32 is directly connected, Serial0/0/0
R 172.16.30.0/24 [120/1] via 172.16.20.2, 00:00:07, Serial0/0/0
from Lab B
LabB(config)#
no ip route 172.16.10.0 255.255.255.0 172.16.20.1
LabB(config)#
no ip route 172.16.40.0 255.255.255.0 172.16.30.2
LabB(config)#
router rip
LabB(config-router)#
network 172.16.0.0
LabB(config-router)#
do show ip route
Gateway of last resort is not set
172.16.0.0/16 is variably subnetted, 5 subnets, 2 masks
R 172.16.10.0/24 [120/1] via 172.16.20.1, 00:00:13, Serial0/0/0
from LabA
C 172.16.20.0/24 is directly connected, Serial0/0/0
L 172.16.20.2/32 is directly connected, Serial0/0/0
C 172.16.30.0/24 is directly connected, Serial0/0/1
L 172.16.30.1/32 is directly connected, Serial0/0/1
LabC(config)#
no ip route 172.16.10.0 255.255.255.0 172.16.30.1
LabC(config)#
no ip route 172.16.20.0 255.255.255.0 172.16.30.1
LabC(config)#
router rip
LabC(config-router)#
network 172.16.0.0
LabC(config-router)#
do show ip route
Gateway of last resort is not set
172.16.0.0/16 is variably subnetted, 3 subnets, 2 masks
R 172.16.20.0/24 [120/1] via 172.16.30.1, 00:00:05, Serial0/0/0
from LabB
C 172.16.30.0/24 is directly connected, Serial0/0/0
L 172.16.30.2/32 is directly connected, Serial0/0/0
Chapter 8 Review Questions
1. The Acme company uses a router named Gateway to connect to its ISP. The address of the ISP router is 206.143.5.2.
Which three commands could be configured on the gateway router to allow internet access to the entire network?
Set a default route:
Gateway(config)#
ip route 0.0.0.0 0.0.0.0 206.143.5.2 next hop IP
Gateway(config)#
ip route 0.0.0.0 0.0.0.0 S/0 exit interface instead of next hop IP
Gateway(config)#
ip default-network 206.143.5.0 next hop IP
2. What command will prevent RIP routing updates from exiting an interface but will sill allow the interface to receive RIP updates?
Router(config-if)#
passive-interface
3. Which two statemnts are true about ip route 172.16.4.0 255.255.255.0 192.168.4.2?
the command establishes a static route
the default admin distance is used (since we didnt give an AD argument)
4. What two destination addresses will be used by HostA to send data to the HTTPS server as shown in the following network?
MAC of RouterA f0/0 interface
IP address of the server
5. Which two statements are true about this output?
RIP: received v1 update from 192.168.40.2 on S0/1
192.168.50.0 in 16 hops (inaccessible)
RIP: sending v1 update to 255.255.255.255 via F0/0 (192.168.30.1)
RIP: build update entries
network 192.168.20.0 metric 1
network 192.168.40.0 metric 1
network 192.168.50.0 metric 16
RIP: sending v1 update to 255.255.255.255 via S0/1 (192.168.40.1)
true:
there are at least two routers exchanging information
192.168.40.2 will be successful
FALSE
there are three interfaces on the router participating in this update
false because we only see two interfaces represented in the output: S0/1(twice) and F0/0
a ping to 192.168.50.1 will be successful
false because that route has a metric of 16; it's unreachable
6. Describe split horizon
will not advertise a route back the the same router it was learned from
7. Which would be true if HostA is trying to communicate to HostB and interface F0/0 of RouterC goes down, as shown in the graphic?
RouterC will send an ICMP 'destination unreachable type' message to inform HostA that HostB is unreachable
8. Which two statements are true regarding classless routing protocols?
VLSM is permitted
RIPv2 supports classless
9. Which two are true regarding distance-vector vs link-state?
Distance vector sends the whole routing table out all active interfaces(even if a router isnt on the other end)at periodic time intervals
Link-state sends updates containing the state of its own links to all routers in the inter-network
10. Which command display RIP routing updates?
debug ip rip
11. What does RIPv2 use to prvent routing loops?
split horizon stops an update from being send on the same interface it was received
holdown timers allow time for a network to become stable in the case of a flapping link
12. A network administrator views the output from the show ip route command. A network that is advertised
by both RIP and EIGRP appears in the routing table flagged an EIGRP route. Why is the RIP route to this network not used in this routing table?
EIGRP has a lower AD.
RIP=120
OSPP=110
IGRP=110
EIGRP=90
13. You type debug ip rip on your router console and see that 172.16.10.0 is being advertised to you with a metric of 16. What does this mean?
it is inaccessible. in RIP if you see a route advertised with a metric of 16, it's inaccessible
14. What metric does RIPv2 use to find the best path to the remote network?
distance aka hop count
15. The Corporate router receives an IP packet with a source IP address of 192.168.214.20 and a destination address of 192.168.22.3. Looking at the output from the Corp router,
what will the router do with this packet?
Corp# show ip route
[cut]
R 192.168.215.0 [120/2] via 192.168.20.2, Serail0/0
R 192.168.115.0 [120/1] via 192.168.20.0, Serial0/0
R 192.168.30.0 [120/1] via 192.168.20.2, Serial0/0
C 192.168.20.0 is directly connected, Serial0/0
C 192.168.214.0 is directly connected, FastEthernet0/0
Since there is no route to that network, the router will discard the packet and send an ICMP destination unreachable message out F0/0 back the the source network
16. If your routing table has a static, a RIP and an EIGRP route to the same network, which route will be used by default?
Static routes have an admin distance of 1 by default. Unless you change it, a static route will always be used over any other
dynamically learned route.
17. You have the following routing table. Which network will NOT be placed in the neighbor routing table?
R 192.168.30.0/24 [120/1] via 192.168.40.1, Serial 0
C 192.168.40.0/24 is directly connected, Serial 0
172.16.0.0/2 is subnetted, 1 subnets
C 172.16.30.0 is directly connected, Loopback0
R 192.168.20.0/24 [120/1] via 192.168.40.1, Serial 0
R 10.0.0.0/8 [120/15] via 192.168.40.1, Serial 0
C 192.168.50.0/24 is directly connected, Ethernet 0
10.0.0.0 cant be placed in neighboring routing table because it is at 15 hops. 16 hops is invalid in RIP
18. Two connected routers are configured only with RIP. What will be the result when a router receives a routing update that contains a
higher-cost path to a network already in it's routing table?
The router will ignore the update because it is higher cost. When a routing update is received, the router first checks the AD and always chooses
the route with the lowest AD.
19.Which is true about route poisoning?
The router sets the metric for a downed link to "infinity".
20. Which is true about RIPv2?
it has all the same timers as RIPv1
------------------------------------------------------------------------------
END CHAPTER 8
54 hours 1-28 thru 2-14-22
original total 143 hours
11.5 hours review 12-23,24,26-22
review total hours 32
book page 428/822
avg 20 min/page (reading and exercises/labs)
Chapter 9 EIGRP and OSPF
pages 427-502, start 2-14-22-M
What is EIGRP?
Note it's not officially on CCNA 200-301 but it is still important to learn
Enhanced IGRP is a classless, enchanced distance vector protocol that uses the concept of an autonomous system to describe
the set of contigous routers that run the same routing protocol and share routing information.
Features:
Support for IP and IPv6 via protocol-dependent modules (seperate routing tables)
Considered classless
Support for summaries and discontiguous networks
Eficient neighbor discovery
communication via RTP- Reliable Transport Protocol
best path selection via Diffusing Updae Algorithm DUAL
Cisco considers EIGRP a "distance-vector" routing protocol
or an "advanced distance-vector" protocol
or a "hybrid" protocol
Configuring EIGRP on our network
------------------------------------------------------------------------------------------------------------------------------------
Corp(config)#
router eigrp ?
<1-65535> Autonomous system number
Corp(config)#
router eigrp 10
R2(config-router)#
network 10.0.0.0
after eigrp on R1- links from Corp to R1 are up
%DUAL-5-NBRCHANGE: IP-EIGRP 10: Neighbor 10.1.3.2 (Serial0/0/1) is up: new adjacency
%DUAL-5-NBRCHANGE: IP-EIGRP 10: Neighbor 10.1.2.2 (Serial0/0/0) is up: new adjacency
after eigrp on R2- link from Corp to R2 is up
%DUAL-5-NBRCHANGE: IP-EIGRP 10: Neighbor 10.1.4.2 (Serial0/1/0) is up: new adjacency
after eigrp on R3- link from Corp to R3 is up
%DUAL-5-NBRCHANGE: IP-EIGRP 10: Neighbor 10.1.5.2 (FastEthernet0/0) is up: new adjacency
------------------------------------------------------------------------------------------------------------------------------------
R1(config)#
router eigrp 10
R1(config-router)#
network 10.0.0.0
after eigrp on R1- link from R1 to Corp is up
%DUAL-5-NBRCHANGE: IP-EIGRP 10: Neighbor 10.1.3.1 (Serial0/0/1) is up: new adjacency
%DUAL-5-NBRCHANGE: IP-EIGRP 10: Neighbor 10.1.2.1 (Serial0/0/0) is up: new adjacency
R1(config-router)#
network 192.168.10.0
R1(config-router)#
network 192.168.20.0
------------------------------------------------------------------------------------------------------------------------------------
R2(config)#
router eigrp 10
R2(config-router)#
network 10.0.0.0
after eigrp on R2- link from R2 to Corp is up
%DUAL-5-NBRCHANGE: IP-EIGRP 10: Neighbor 10.1.4.1 (Serial0/0/0) is up: new adjacency
R1(config-router)#
network 192.168.30.0
R1(config-router)#
network 192.168.40.0
------------------------------------------------------------------------------------------------------------------------------------
R3(config)#
router eigrp 10
R3(config-router)#
network 10.0.0.0
after eigrp on R3- link from R3 to Corp is up
%DUAL-5-NBRCHANGE: IP-EIGRP 10: Neighbor 10.1.5.1 (FastEthernet0/0) is up: new adjacency
R1(config-router)#
network 172.16.0.0
------------------------------------------------------------------------------------------------------------------------------------
Corp#
show ip route
Gateway of last resort is not set
Gateway of last resort is not set
10.0.0.0/8 is variably subnetted, 10 subnets, 2 masks
C 10.1.1.0/24 is directly connected, Vlan1
L 10.1.1.1/32 is directly connected, Vlan1
C 10.1.2.0/24 is directly connected, Serial0/0/0
L 10.1.2.1/32 is directly connected, Serial0/0/0
C 10.1.3.0/24 is directly connected, Serial0/0/1
L 10.1.3.1/32 is directly connected, Serial0/0/1
C 10.1.4.0/24 is directly connected, Serial0/1/0
L 10.1.4.1/32 is directly connected, Serial0/1/0
C 10.1.5.0/24 is directly connected, FastEthernet0/0
L 10.1.5.1/32 is directly connected, FastEthernet0/0
172.16.0.0/16 is variably subnetted, 2 subnets, 2 masks
R 172.16.0.0/16 [120/1] via 10.1.5.2, 00:00:17, FastEthernet0/0
D 172.16.10.0/24 [90/28160] via 10.1.5.2, 00:00:16, FastEthernet0/0
via R3
D 192.168.10.0/24 [90/2172416] via 10.1.2.2, 00:19:13, Serial0/0/0
[90/2172416] via 10.1.3.2, 00:19:13, Serial0/0/1
D 192.168.20.0/24 [90/2172416] via 10.1.3.2, 00:19:05, Serial0/0/1
[90/2172416] via 10.1.2.2, 00:19:05, Serial0/0/0
via R1
D 192.168.30.0/24 [90/2172416] via 10.1.4.2, 00:01:31, Serial0/1/0
D 192.168.40.0/24 [90/2172416] via 10.1.4.2, 00:01:08, Serial0/1/0
via R2
The "D" routes are for DUAL- Diffusing Update Algorithm, indicating they are EIGRP routes.
Note that we have RIP and EIGRP set currently
------------------------------------------------------------------------------------------------------------------------------------
R1#
show ip route
Gateway of last resort is not set
10.0.0.0/8 is variably subnetted, 6 subnets, 2 masks
D 10.0.0.0/8 is a summary, 00:25:28, Null0
D 10.1.1.0/24 [90/27769856] via 10.1.2.1, 00:31:33, Serial0/0/0
[90/27769856] via 10.1.3.1, 00:31:30, Serial0/0/1
via Corp
C 10.1.2.0/24 is directly connected, Serial0/0/0
C 10.1.3.0/24 is directly connected, Serial0/0/1
D 10.1.4.0/24 [90/2681856] via 10.1.2.1, 00:31:33, Serial0/0/0
[90/2681856] via 10.1.3.1, 00:31:30, Serial0/0/1
D 10.1.5.0/24 [90/2172416] via 10.1.2.1, 00:31:33, Serial0/0/0
[90/2172416] via 10.1.3.1, 00:31:30, Serial0/0/1
via Corp
172.16.0.0/16 is variably subnetted, 2 subnets, 2 masks
R 172.16.0.0/16 [120/2] via 10.1.2.1, 00:00:07, Serial0/0/0
[120/2] via 10.1.3.1, 00:00:07, Serial0/0/1
D 172.16.10.0/24 [90/2172416] via 10.1.2.1, 00:06:31, Serial0/0/0
[90/2172416] via 10.1.3.1, 00:06:31, Serial0/0/1
via Corp
C 192.168.10.0/24 is directly connected, FastEthernet0/0
C 192.168.20.0/24 is directly connected, FastEthernet0/1
D 192.168.30.0/24 [90/2684416] via 10.1.3.1, 00:07:46, Serial0/0/1
[90/2684416] via 10.1.2.1, 00:07:46, Serial0/0/0
D 192.168.40.0/24 [90/2684416] via 10.1.2.1, 00:07:23, Serial0/0/0
[90/2684416] via 10.1.3.1, 00:07:23, Serial0/0/1
via Corp
------------------------------------------------------------------------------------------------------------------------------------
R2#
show ip route
Gateway of last resort is not set
10.0.0.0/8 is variably subnetted, 6 subnets, 2 masks
D 10.0.0.0/8 is a summary, 00:13:09, Null0
D 10.1.1.0/24 [90/27769856] via 10.1.4.1, 00:36:53, Serial0/0/0
D 10.1.2.0/24 [90/2681856] via 10.1.4.1, 00:36:53, Serial0/0/0
D 10.1.3.0/24 [90/2681856] via 10.1.4.1, 00:36:53, Serial0/0/0
via Corp
C 10.1.4.0/24 is directly connected, Serial0/0/0
D 10.1.5.0/24 [90/2172416] via 10.1.4.1, 00:36:53, Serial0/0/0
via Corp
172.16.0.0/16 is variably subnetted, 2 subnets, 2 masks
R 172.16.0.0/16 [120/2] via 10.1.4.1, 00:00:23, Serial0/0/0
D 172.16.10.0/24 [90/2172416] via 10.1.4.1, 00:11:54, Serial0/0/0
via Corp
D 192.168.10.0/24 [90/2684416] via 10.1.4.1, 00:30:51, Serial0/0/0
D 192.168.20.0/24 [90/2684416] via 10.1.4.1, 00:30:43, Serial0/0/0
via Corp
C 192.168.30.0/24 is directly connected, FastEthernet0/0
C 192.168.40.0/24 is directly connected, FastEthernet0/1
------------------------------------------------------------------------------------------------------------------------------------
R3#
show ip route
Gateway of last resort is 10.1.5.1 to network 0.0.0.0
10.0.0.0/8 is variably subnetted, 6 subnets, 2 masks
D 10.1.1.0/24 [90/25628160] via 10.1.5.1, 00:37:20, FastEthernet0/0
D 10.1.2.0/24 [90/2172416] via 10.1.5.1, 00:37:15, FastEthernet0/0
D 10.1.3.0/24 [90/2172416] via 10.1.5.1, 00:37:20, FastEthernet0/0
D 10.1.4.0/24 [90/2172416] via 10.1.5.1, 00:37:20, FastEthernet0/0
via Corp
C 10.1.5.0/24 is directly connected, FastEthernet0/0
L 10.1.5.2/32 is directly connected, FastEthernet0/0
172.16.0.0/16 is variably subnetted, 2 subnets, 2 masks
C 172.16.10.0/24 is directly connected, Dot11Radio0/0/0
L 172.16.10.1/32 is directly connected, Dot11Radio0/0/0
D 192.168.10.0/24 [90/2174976] via 10.1.5.1, 00:31:10, FastEthernet0/0
D 192.168.20.0/24 [90/2174976] via 10.1.5.1, 00:31:02, FastEthernet0/0
via Corp and R1
D 192.168.30.0/24 [90/2174976] via 10.1.5.1, 00:13:28, FastEthernet0/0
D 192.168.40.0/24 [90/2174976] via 10.1.5.1, 00:13:05, FastEthernet0/0
via Corp and R2
S* 0.0.0.0/0 [1/0] via 10.1.5.1
------------------------------------------------------------------------------------------------------------------------------------
turn off auto summary on each router
------------------------------------------------------------------------------------------------------------------------------------
Corp(config)#
router eigrp 10
Corp(config-router)#
no auto-summary
------------------------------------------------------------------------------------------------------------------------------------
R1(config)#
router eigrp 10
R1(config-router)#
no auto-summary
------------------------------------------------------------------------------------------------------------------------------------
R2(config)#
router eigrp 10
R2(config-router)#
no auto-summary
------------------------------------------------------------------------------------------------------------------------------------
R3(config)#
router eigrp 10
R3(config-router)#
no auto-summary
------------------------------------------------------------------------------------------------------------------------------------
compare Corp before and after auto summary turned off
------------------------------------------------------------------------------------------------------------------------------------
auto summary on
Corp#
show ip route
Gateway of last resort is not set
10.0.0.0/8 is variably subnetted, 10 subnets, 2 masks
C 10.1.1.0/24 is directly connected, Vlan1
L 10.1.1.1/32 is directly connected, Vlan1
C 10.1.2.0/24 is directly connected, Serial0/0/0
L 10.1.2.1/32 is directly connected, Serial0/0/0
C 10.1.3.0/24 is directly connected, Serial0/0/1
L 10.1.3.1/32 is directly connected, Serial0/0/1
C 10.1.4.0/24 is directly connected, Serial0/1/0
L 10.1.4.1/32 is directly connected, Serial0/1/0
C 10.1.5.0/24 is directly connected, FastEthernet0/0
L 10.1.5.1/32 is directly connected, FastEthernet0/0
172.16.0.0/16 is variably subnetted, 2 subnets, 2 masks
R 172.16.0.0/16 [120/1] via 10.1.5.2, 00:00:17, FastEthernet0/0
D 172.16.10.0/24 [90/28160] via 10.1.5.2, 00:00:16, FastEthernet0/0
via R3
D 192.168.10.0/24 [90/2172416] via 10.1.2.2, 00:19:13, Serial0/0/0
[90/2172416] via 10.1.3.2, 00:19:13, Serial0/0/1
D 192.168.20.0/24 [90/2172416] via 10.1.3.2, 00:19:05, Serial0/0/1
[90/2172416] via 10.1.2.2, 00:19:05, Serial0/0/0
via R1
D 192.168.30.0/24 [90/2172416] via 10.1.4.2, 00:01:31, Serial0/1/0
D 192.168.40.0/24 [90/2172416] via 10.1.4.2, 00:01:08, Serial0/1/0
via R2
auto summary off
Corp#
show ip route
Gateway of last resort is not set
10.0.0.0/8 is variably subnetted, 10 subnets, 2 masks
C 10.1.1.0/24 is directly connected, Vlan1
L 10.1.1.1/32 is directly connected, Vlan1
C 10.1.2.0/24 is directly connected, Serial0/0/0
L 10.1.2.1/32 is directly connected, Serial0/0/0
C 10.1.3.0/24 is directly connected, Serial0/0/1
L 10.1.3.1/32 is directly connected, Serial0/0/1
C 10.1.4.0/24 is directly connected, Serial0/1/0
L 10.1.4.1/32 is directly connected, Serial0/1/0
C 10.1.5.0/24 is directly connected, FastEthernet0/0
L 10.1.5.1/32 is directly connected, FastEthernet0/0
172.16.0.0/16 is variably subnetted, 2 subnets, 2 masks
R 172.16.0.0/16 [120/1] via 10.1.5.2, 00:00:12, FastEthernet0/0
D 172.16.10.0/24 [90/28160] via 10.1.5.2, 00:45:29, FastEthernet0/0
via R3
D 192.168.10.0/24 [90/2172416] via 10.1.2.2, 00:01:08, Serial0/0/0
[90/2172416] via 10.1.3.2, 00:01:08, Serial0/0/1
D 192.168.20.0/24 [90/2172416] via 10.1.2.2, 00:01:08, Serial0/0/0
[90/2172416] via 10.1.3.2, 00:01:08, Serial0/0/1
via R1
D 192.168.30.0/24 [90/2172416] via 10.1.4.2, 00:00:46, Serial0/1/0
D 192.168.40.0/24 [90/2172416] via 10.1.4.2, 00:00:46, Serial0/1/0
via R2
We are still seeing an auto summarized route- 172.16.0.0 coming from R3.
The book discusses enabling EIGRP auto summary on all four routers- nothing is said about disabling it within RIP or turning off RIP.
RIP auto summarizes by default. We cant get rid of this auto summary route while RIP is on.
Moving on...
VERIFYING EIGRP
several commands available to verify and troubleshoot
show ip route
show the entire routing table
show ip route eigrp
show only EIGRP entries in the routing table
show ip eigrp neighbors
show all EIGRP neigbors
show ip eigrp topology
show entries in the EIGRP topology table
show ip protocols
shows routing protocols configuration
debug eigrp packet
shows hello packets sent/received between adjacent routers
debug ip eigrp events
shows EIGRP changes and updates as they occur on your network
lets take a look at the state of our 4 routers. RIP and EIGRP are running on each.
Notice how this command is giving different outputs between the two different IOS versions
IOS 15.1
Corp#
show ip protocols
Routing Protocol is "eigrp 10 "
Outgoing update filter list for all interfaces is not set
Incoming update filter list for all interfaces is not set
Default networks flagged in outgoing updates
Default networks accepted from incoming updates
Redistributing: eigrp 10
EIGRP-IPv4 Protocol for AS(10)
Metric weight K1=1, K2=0, K3=1, K4=0, K5=0
NSF-aware route hold timer is 240
Router-ID: 10.1.1.1
Topology : 0 (base)
Active Timer: 3 min
Distance: internal 90 external 170
Maximum path: 4
Maximum hopcount 100
Maximum metric variance 1
Automatic Summarization: disabled
Automatic address summarization:
Maximum path: 4
Routing for Networks:
10.0.0.0
Routing Information Sources:
Gateway Distance Last Update
10.1.5.2 90 0
10.1.3.2 90 6464
10.1.2.2 90 6795
10.1.4.2 90 7955
Distance: internal 90 external 170
Routing Protocol is "rip"
Sending updates every 30 seconds, next due in 10 seconds
Invalid after 180 seconds, hold down 180, flushed after 240
Outgoing update filter list for all interfaces is not set
Incoming update filter list for all interfaces is not set
Redistributing: rip
Default version control: send version 2, receive 2
Interface Send Recv Triggered RIP Key-chain
Vlan1 2 2
FastEthernet0/0 2 2
Serial0/1/0 2 2
Serial0/0/1 2 2
Serial0/0/0 2 2
Automatic network summarization is in effect
Maximum path: 4
Routing for Networks:
10.0.0.0
Passive Interface(s):
Routing Information Sources:
Gateway Distance Last Update
10.1.5.2 120 00:00:12
10.1.3.2 120 00:00:16
10.1.2.2 120 00:00:16
10.1.4.2 120 00:00:13
Distance: (default is 120)
IOS 12.4
R1#
show ip protocols
Routing Protocol is "eigrp 10 "
Outgoing update filter list for all interfaces is not set
Incoming update filter list for all interfaces is not set
Default networks flagged in outgoing updates
Default networks accepted from incoming updates
EIGRP metric weight K1=1, K2=0, K3=1, K4=0, K5=0
EIGRP maximum hopcount 100
EIGRP maximum metric variance 1
Redistributing: eigrp 10
Automatic network summarization is not in effect
Maximum path: 4
Routing for Networks:
10.0.0.0
192.168.10.0
192.168.20.0
Routing Information Sources:
Gateway Distance Last Update
10.1.3.1 90 6465
10.1.2.1 90 6794
Distance: internal 90 external 170
Routing Protocol is "rip"
Sending updates every 30 seconds, next due in 21 seconds
Invalid after 180 seconds, hold down 180, flushed after 240
Outgoing update filter list for all interfaces is not set
Incoming update filter list for all interfaces is not set
Redistributing: rip
Default version control: send version 2, receive 2
Interface Send Recv Triggered RIP Key-chain
FastEthernet0/0 2 2
FastEthernet0/1 2 2
Serial0/0/0 2 2
Serial0/0/1 2 2
Automatic network summarization is not in effect
Maximum path: 4
Routing for Networks:
10.0.0.0
192.168.10.0
192.168.20.0
Passive Interface(s):
Routing Information Sources:
Gateway Distance Last Update
10.1.3.1 120 00:00:06
10.1.2.1 120 00:00:06
Distance: (default is 120)
IOS 12.4
R2#
show ip protocols
Routing Protocol is "eigrp 10 "
Outgoing update filter list for all interfaces is not set
Incoming update filter list for all interfaces is not set
Default networks flagged in outgoing updates
Default networks accepted from incoming updates
EIGRP metric weight K1=1, K2=0, K3=1, K4=0, K5=0
EIGRP maximum hopcount 100
EIGRP maximum metric variance 1
Redistributing: eigrp 10
Automatic network summarization is not in effect
Maximum path: 4
Routing for Networks:
10.0.0.0
192.168.30.0
192.168.40.0
Routing Information Sources:
Gateway Distance Last Update
10.1.4.1 90 7955
Distance: internal 90 external 170
Routing Protocol is "rip"
Sending updates every 30 seconds, next due in 11 seconds
Invalid after 180 seconds, hold down 180, flushed after 240
Outgoing update filter list for all interfaces is not set
Incoming update filter list for all interfaces is not set
Redistributing: rip
Default version control: send version 2, receive 2
Interface Send Recv Triggered RIP Key-chain
FastEthernet0/0 2 2
FastEthernet0/1 2 2
Serial0/0/0 2 2
Automatic network summarization is in effect
Maximum path: 4
Routing for Networks:
10.0.0.0
192.168.30.0
192.168.40.0
Passive Interface(s):
Routing Information Sources:
Gateway Distance Last Update
10.1.4.1 120 00:00:20
Distance: (default is 120)
IOS 15.1
R3#
show ip protocols
Routing Protocol is "eigrp 10 "
Outgoing update filter list for all interfaces is not set
Incoming update filter list for all interfaces is not set
Default networks flagged in outgoing updates
Default networks accepted from incoming updates
Redistributing: eigrp 10
EIGRP-IPv4 Protocol for AS(10)
Metric weight K1=1, K2=0, K3=1, K4=0, K5=0
NSF-aware route hold timer is 240
Router-ID: 10.1.5.2
Topology : 0 (base)
Active Timer: 3 min
Distance: internal 90 external 170
Maximum path: 4
Maximum hopcount 100
Maximum metric variance 1
Automatic Summarization: disabled
Automatic address summarization:
Maximum path: 4
Routing for Networks:
10.0.0.0
172.16.0.0
Routing Information Sources:
Gateway Distance Last Update
10.1.5.1 90 0
Distance: internal 90 external 170
Routing Protocol is "rip"
Sending updates every 30 seconds, next due in 27 seconds
Invalid after 180 seconds, hold down 180, flushed after 240
Outgoing update filter list for all interfaces is not set
Incoming update filter list for all interfaces is not set
Redistributing: rip
Default version control: send version 2, receive 2
Interface Send Recv Triggered RIP Key-chain
Dot11Radio0/0/0 2 2
FastEthernet0/0 2 2
Automatic network summarization is not in effect
Maximum path: 4
Routing for Networks:
10.0.0.0
172.16.0.0
Passive Interface(s):
Routing Information Sources:
Gateway Distance Last Update
10.1.5.1 120 00:00:02
Distance: (default is 120)
I'm also noticing that we have inconsistent auto-summarization settings- I was having trouble with this earlier. The book discusses
getting rid of the 172.16.0.0 summarized route in the EIGRP settings. I was not able to get rid of it, I think because RIP is still on, and RIP forces auto-summary
Part of the challenge here is that the book is strictly dealing with IOS 12.4
I will now make sure to turn auto summary off for both RIP and EIGRP on each of the four routers.
OK the part I am forgetting is that we are running RIP V2 which does not force auto-summary but runs it optionally, and we must turn it off to avoid auto summarization.
Corp(config)#
router rip
Corp(config-router)#
no auto-summary
Corp(config-router)#
router eigrp 10
Corp(config-router)#
no auto-summary
R1(config)#
router rip
R1(config-router)#
no auto-summary
R1(config-router)#
router eigrp 10
R1(config-router)#
no auto-summary
R1(config)#
router rip
R1(config-router)#
no auto-summary
R1(config-router)#
router eigrp 10
R2(config-router)#
no auto-summary
R3(config)#
router rip
R3(config-router)#
no auto-summary
R3(config-router)#
router eigrp 10
R3(config-router)#
no auto-summary
and lets see how the output looks now. This time I'll do show ip protocols and
show ip route side by side for each router
IOS 15.1
Corp#
show ip protocols
Routing Protocol is "eigrp 10 "
Outgoing update filter list for all interfaces is not set
Incoming update filter list for all interfaces is not set
Default networks flagged in outgoing updates
Default networks accepted from incoming updates
Redistributing: eigrp 10
EIGRP-IPv4 Protocol for AS(10)
Metric weight K1=1, K2=0, K3=1, K4=0, K5=0
NSF-aware route hold timer is 240
Router-ID: 10.1.1.1
Topology : 0 (base)
Active Timer: 3 min
Distance: internal 90 external 170
Maximum path: 4
Maximum hopcount 100
Maximum metric variance 1
Automatic Summarization: disabled
Automatic address summarization:
Maximum path: 4
Routing for Networks:
10.0.0.0
Routing Information Sources:
Gateway Distance Last Update
10.1.5.2 90 0
10.1.3.2 90 6464
10.1.2.2 90 6795
10.1.4.2 90 7955
Distance: internal 90 external 170
Routing Protocol is "rip" doesnt necessarily mean RIPv1
Sending updates every 30 seconds, next due in 3 seconds
Invalid after 180 seconds, hold down 180, flushed after 240
Outgoing update filter list for all interfaces is not set
Incoming update filter list for all interfaces is not set
Redistributing: rip
Default version control: send version 2, receive 2 RIPv2 is specified
Interface Send Recv Triggered RIP Key-chain
Vlan1 2 2
FastEthernet0/0 2 2
Serial0/1/0 2 2
Serial0/0/1 2 2
Serial0/0/0 2 2
Automatic network summarization is not in effect
Maximum path: 4
Routing for Networks:
10.0.0.0
Passive Interface(s):
Routing Information Sources:
Gateway Distance Last Update
10.1.5.2 120 00:00:02
10.1.3.2 120 00:00:21
10.1.2.2 120 00:00:21
10.1.4.2 120 00:00:04
Distance: (default is 120)
IOS 15.1
Corp#
show ip route
Gateway of last resort is not set
10.0.0.0/8 is variably subnetted, 10 subnets, 2 masks
C 10.1.1.0/24 is directly connected, Vlan1
L 10.1.1.1/32 is directly connected, Vlan1
C 10.1.2.0/24 is directly connected, Serial0/0/0
L 10.1.2.1/32 is directly connected, Serial0/0/0
C 10.1.3.0/24 is directly connected, Serial0/0/1
L 10.1.3.1/32 is directly connected, Serial0/0/1
C 10.1.4.0/24 is directly connected, Serial0/1/0
L 10.1.4.1/32 is directly connected, Serial0/1/0
C 10.1.5.0/24 is directly connected, FastEthernet0/0
L 10.1.5.1/32 is directly connected, FastEthernet0/0
172.16.0.0/24 is subnetted, 1 subnets
D 172.16.10.0/24 [90/28160] via 10.1.5.2, 00:57:25, FastEthernet0/0
D 192.168.10.0/24 [90/2172416] via 10.1.3.2, 00:57:20, Serial0/0/1
[90/2172416] via 10.1.2.2, 00:57:20, Serial0/0/0
D 192.168.20.0/24 [90/2172416] via 10.1.3.2, 00:57:20, Serial0/0/1
[90/2172416] via 10.1.2.2, 00:57:20, Serial0/0/0
D 192.168.30.0/24 [90/2172416] via 10.1.4.2, 00:57:19, Serial0/1/0
D 192.168.40.0/24 [90/2172416] via 10.1.4.2, 00:57:19, Serial0/1/0
IOS 12.4
R1#
show ip protocols
Routing Protocol is "eigrp 10 "
Outgoing update filter list for all interfaces is not set
Incoming update filter list for all interfaces is not set
Default networks flagged in outgoing updates
Default networks accepted from incoming updates
EIGRP metric weight K1=1, K2=0, K3=1, K4=0, K5=0
EIGRP maximum hopcount 100
EIGRP maximum metric variance 1
Redistributing: eigrp 10
Automatic network summarization is not in effect
Maximum path: 4
Routing for Networks:
10.0.0.0
192.168.10.0
192.168.20.0
Routing Information Sources:
Gateway Distance Last Update
10.1.3.1 90 6465
10.1.2.1 90 6794
Distance: internal 90 external 170
Routing Protocol is "rip"
Sending updates every 30 seconds, next due in 26 seconds
Invalid after 180 seconds, hold down 180, flushed after 240
Outgoing update filter list for all interfaces is not set
Incoming update filter list for all interfaces is not set
Redistributing: rip
Default version control: send version 2, receive 2
Interface Send Recv Triggered RIP Key-chain
FastEthernet0/0 2 2
FastEthernet0/1 2 2
Serial0/0/0 2 2
Serial0/0/1 2 2
Automatic network summarization is not in effect
Maximum path: 4
Routing for Networks:
10.0.0.0
192.168.10.0
192.168.20.0
Passive Interface(s):
Routing Information Sources:
Gateway Distance Last Update
10.1.3.1 120 00:00:03
10.1.2.1 120 00:00:03
Distance: (default is 120)
IOS 12.4
R1#
show ip route
Gateway of last resort is not set
10.0.0.0/24 is subnetted, 5 subnets
D 10.1.1.0 [90/27769856] via 10.1.3.1, 00:54:47, Serial0/0/1
[90/27769856] via 10.1.2.1, 00:54:47, Serial0/0/0
C 10.1.2.0 is directly connected, Serial0/0/0
C 10.1.3.0 is directly connected, Serial0/0/1
D 10.1.4.0 [90/2681856] via 10.1.3.1, 00:54:47, Serial0/0/1
[90/2681856] via 10.1.2.1, 00:54:47, Serial0/0/0
D 10.1.5.0 [90/2172416] via 10.1.3.1, 00:54:47, Serial0/0/1
[90/2172416] via 10.1.2.1, 00:54:47, Serial0/0/0
172.16.0.0/24 is subnetted, 1 subnets
D 172.16.10.0 [90/2172416] via 10.1.3.1, 00:54:47, Serial0/0/1
[90/2172416] via 10.1.2.1, 00:54:47, Serial0/0/0
C 192.168.10.0/24 is directly connected, FastEthernet0/0
C 192.168.20.0/24 is directly connected, FastEthernet0/1
D 192.168.30.0/24 [90/2684416] via 10.1.3.1, 00:54:46, Serial0/0/1
[90/2684416] via 10.1.2.1, 00:54:46, Serial0/0/0
D 192.168.40.0/24 [90/2684416] via 10.1.3.1, 00:54:46, Serial0/0/1
[90/2684416] via 10.1.2.1, 00:54:46, Serial0/0/0
note that the DUAL routes being advertised from the 10.0.0.0 networks are all specific to the third octet.. that's because we are reading those routes
from their source, aka the router which they are directly connected to, Corp.
and on Corp, those networks were added to the interfaces with a /24 mask.
so even though our EIGRP config doesnt specifically include /24 networks.. we told it to include anything with a 10.x.x.x
Corp is advertising to R1 our /24 network interfaces that have a 10 in the first octet, EXCEPT the two which are directly connected to R1
10.1.1.0
10.1.4.0
10.1.5.0
are assumed to be the subnets based on the info we configured, which was 10.1.4.1/24 on corp, and 10.1.4.2/24 on r2 s0/0/0
nowhere in this configuration, have we entered the 10.1.4.0 network.
EIGRP is figuring it out based on the /24 mask we gave when assiging he IPs to the interfaces
IOS 12.4
R2#
show ip protocols
Routing Protocol is "eigrp 10 "
Outgoing update filter list for all interfaces is not set
Incoming update filter list for all interfaces is not set
Default networks flagged in outgoing updates
Default networks accepted from incoming updates
EIGRP metric weight K1=1, K2=0, K3=1, K4=0, K5=0
EIGRP maximum hopcount 100
EIGRP maximum metric variance 1
Redistributing: eigrp 10
Automatic network summarization is not in effect
Maximum path: 4
Routing for Networks:
10.0.0.0
192.168.30.0
192.168.40.0
Routing Information Sources:
Gateway Distance Last Update
10.1.4.1 90 7955
Distance: internal 90 external 170
Routing Protocol is "rip"
Sending updates every 30 seconds, next due in 18 seconds
Invalid after 180 seconds, hold down 180, flushed after 240
Outgoing update filter list for all interfaces is not set
Incoming update filter list for all interfaces is not set
Redistributing: rip
Default version control: send version 2, receive 2
Interface Send Recv Triggered RIP Key-chain
FastEthernet0/0 2 2
FastEthernet0/1 2 2
Serial0/0/0 2 2
Automatic network summarization is not in effect
Maximum path: 4
Routing for Networks:
10.0.0.0
192.168.30.0
192.168.40.0
Passive Interface(s):
Routing Information Sources:
Gateway Distance Last Update
10.1.4.1 120 00:00:07
Distance: (default is 120)
IOS 12.4
R2#
show ip route
Gateway of last resort is not set
10.0.0.0/24 is subnetted, 5 subnets
D 10.1.1.0 [90/27769856] via 10.1.4.1, 00:59:10, Serial0/0/0
D 10.1.2.0 [90/2681856] via 10.1.4.1, 00:59:10, Serial0/0/0
D 10.1.3.0 [90/2681856] via 10.1.4.1, 00:59:10, Serial0/0/0
C 10.1.4.0 is directly connected, Serial0/0/0
D 10.1.5.0 [90/2172416] via 10.1.4.1, 00:59:10, Serial0/0/0
172.16.0.0/24 is subnetted, 1 subnets
D 172.16.10.0 [90/2172416] via 10.1.4.1, 00:59:10, Serial0/0/0
D 192.168.10.0/24 [90/2684416] via 10.1.4.1, 00:59:10, Serial0/0/0
D 192.168.20.0/24 [90/2684416] via 10.1.4.1, 00:59:10, Serial0/0/0
C 192.168.30.0/24 is directly connected, FastEthernet0/0
C 192.168.40.0/24 is directly connected, FastEthernet0/1
IOS 15.1
R3#
show ip protocols
Routing Protocol is "eigrp 10 "
Outgoing update filter list for all interfaces is not set
Incoming update filter list for all interfaces is not set
Default networks flagged in outgoing updates
Default networks accepted from incoming updates
Redistributing: eigrp 10
EIGRP-IPv4 Protocol for AS(10)
Metric weight K1=1, K2=0, K3=1, K4=0, K5=0
NSF-aware route hold timer is 240
Router-ID: 10.1.5.2
Topology : 0 (base)
Active Timer: 3 min
Distance: internal 90 external 170
Maximum path: 4
Maximum hopcount 100
Maximum metric variance 1
Automatic Summarization: disabled
Automatic address summarization:
Maximum path: 4
Routing for Networks:
10.0.0.0
172.16.0.0
Routing Information Sources:
Gateway Distance Last Update
10.1.5.1 90 0
Distance: internal 90 external 170
Routing Protocol is "rip"
Sending updates every 30 seconds, next due in 15 seconds
Invalid after 180 seconds, hold down 180, flushed after 240
Outgoing update filter list for all interfaces is not set
Incoming update filter list for all interfaces is not set
Redistributing: rip
Default version control: send version 2, receive 2
Interface Send Recv Triggered RIP Key-chain
Dot11Radio0/0/0 2 2
FastEthernet0/0 2 2
Automatic network summarization is not in effect
Maximum path: 4
Routing for Networks:
10.0.0.0
172.16.0.0
Passive Interface(s):
Routing Information Sources:
Gateway Distance Last Update
10.1.5.1 120 00:00:14
Distance: (default is 120)
IOS 15.1
R3#
show ip route
Gateway of last resort is 10.1.5.1 to network 0.0.0.0
10.0.0.0/8 is variably subnetted, 6 subnets, 2 masks
D 10.1.1.0/24 [90/25628160] via 10.1.5.1, 00:59:52, FastEthernet0/0
D 10.1.2.0/24 [90/2172416] via 10.1.5.1, 00:59:47, FastEthernet0/0
D 10.1.3.0/24 [90/2172416] via 10.1.5.1, 00:59:52, FastEthernet0/0
D 10.1.4.0/24 [90/2172416] via 10.1.5.1, 00:59:52, FastEthernet0/0
C 10.1.5.0/24 is directly connected, FastEthernet0/0
L 10.1.5.2/32 is directly connected, FastEthernet0/0
172.16.0.0/16 is variably subnetted, 2 subnets, 2 masks
C 172.16.10.0/24 is directly connected, Dot11Radio0/0/0
L 172.16.10.1/32 is directly connected, Dot11Radio0/0/0
D 192.168.10.0/24 [90/2174976] via 10.1.5.1, 00:59:47, FastEthernet0/0
D 192.168.20.0/24 [90/2174976] via 10.1.5.1, 00:59:47, FastEthernet0/0
D 192.168.30.0/24 [90/2174976] via 10.1.5.1, 00:59:46, FastEthernet0/0
D 192.168.40.0/24 [90/2174976] via 10.1.5.1, 00:59:46, FastEthernet0/0
S* 0.0.0.0/0 [1/0] via 10.1.5.1
Observations:
Since this is a 15.1 router, we always get a "L" local route when
we have a "C" connected route. In R3's case, the 172.16.10.0 network
is directly connected. The interface which connects it, 172.16.10.1,
counts as a "local" route. This is NOT the case on the 12.4 routers.
looking to the left, our protocol output tells us two key facts for both EIGRP and RIP:
Routing for networks:
10.0.0.0
172.16.0.0
R3 is responsible for *sending* data about these two networks to our other EIGRP routers...
"I'm R3 and I can connect you to networks on the R3
router or networks on the Corp router"
Notice how the 192 networks arent listed. R3 isnt connected to a 192 network directly, nor is it connected to a neighbor who is directly connected.
If I, as a client, am sending data to a 192 network from the 172 network, I will start
at R3. Since R3 is receiving routes for the 192 networks via Corp, I will be able to reach a 192 network via Corp.
My connection to corp will happen VIA a "10.0.0.0" route.
R3 is technically only routing for 172 and 10 networks. Beyond that, it could potentially connect to many other different networks. But in terms of the R3 routing table,
all it can offer is a path out to the 172 network or the 10 network
Routing information sources:
10.1.5.1
In this case I can see that R3 is receiving routing data from one interface only,
and that is it's link to Corp. Some of the data we are receiving from Corp actually originates
at other routers, but we cant see that here; the data comes to us from Corp, and that is all we know
EIGRP TERMINOLOGY
FEASIBLE DISTANCE (FD)
the best metric among all paths, including to the next hop neighbor. You will only see the route with the lowest FD appear in the routing table
The FD is calculated by adding the reported distance from the neighbor (AD) plus the metric to that neighbor
ADVERTISED DISTANCE (AD)
the metric of a remote network as reported by a neighbor, listed second in parenthesis in toplogy table
P 192.168.20.0/24, 2 successors, FD is 2172416
via 10.1.3.2 (2172416/28160), Serial0/0/1
feasible / advertised
Neighbor Table
each router keeps state information about adjacent neighbors.. When a new neighbor is learned, the address and interface are recorded.
The neighbor table is stored in RAM.
Sequence numbres are used to match acks with update packets. The last squence number received from a neighbor is recorded so out of order packets
can be detected
Topology Table
acted upon by DUAL Diffusing Update Alogorithm. Contains all destinations advertised by neighboring routers.
For each neighbor, the adversited distance, which comes only from that neighbor's routing table, is recorded
The feasible distance is also recorded.
Feasible Successor
a PATH whose advertised distance is less than the feasible distance of the current succesor, and is considered a backup route.
EIGRP keeps up to 16 feasible successors in the toplogy table.
The one with the best metric (The Successor) is copied and placed into the routing table
Successor
the best route to a remote network, used by EIGRP to forward traffic. It's backed up by a feasible successor, if one is available.
lets demo some more of the commands
VERIFYING EIGRP
several commands available to verify and troubleshoot
show ip route
show the entire routing table
show ip route eigrp
show only EIGRP entries in the routing table
show ip eigrp neighbors
show all EIGRP neigbors
show ip eigrp topology
show entries in the EIGRP topology table
show ip protocols
shows routing protocols configuration
debug eigrp packet
shows hello packets sent/received between adjacent routers
debug ip eigrp events
shows EIGRP changes and updates as they occur on your network
Corp#
show ip eigrp ?
interfaces IP-EIGRP interfaces
neighbors IP-EIGRP neighbors
topology IP-EIGRP Topology Table
traffic IP-EIGRP Traffic Statistics
Corp#
show ip eigrp topology
IP-EIGRP Topology Table for AS 10/ID(10.1.5.1)
Codes: P - Passive, A - Active, U - Update, Q - Query, R - Reply,
r - Reply status
P 10.1.1.0/24, 1 successors, FD is 25625600
via Connected, Vlan1
P 10.1.2.0/24, 1 successors, FD is 2169856
via Connected, Serial0/0/0
P 10.1.3.0/24, 1 successors, FD is 2169856
via Connected, Serial0/0/1
P 10.1.4.0/24, 1 successors, FD is 2169856
via Connected, Serial0/1/0
P 10.1.5.0/24, 1 successors, FD is 28160
via Connected, FastEthernet0/0
P 172.16.10.0/24, 1 successors, FD is 28160
via 10.1.5.2 (28160/25600), FastEthernet0/0
P 192.168.10.0/24, 2 successors, FD is 2172416
via 10.1.3.2 (2172416/28160), Serial0/0/1
via 10.1.2.2 (2172416/28160), Serial0/0/0
P 192.168.20.0/24, 2 successors, FD is 2172416
via 10.1.3.2 (2172416/28160), Serial0/0/1
via 10.1.2.2 (2172416/28160), Serial0/0/0
P 192.168.30.0/24, 1 successors, FD is 2172416
via 10.1.4.2 (2172416/28160), Serial0/1/0
P 192.168.40.0/24, 1 successors, FD is 2172416
via 10.1.4.2 (2172416/28160), Serial0/1/0
the "P" preceding each entry is for PASSIVE
these routes are in a passive state, which is good
if they move to an ACTIVE state, it means the have lost their path in the network and looking for a replacement.
Each entry also shows the FEASIBLE DISTANCE, the next hop address, and the local egress interface
Corp#
show ip eigrp neighbors
IP-EIGRP neighbors for process 10
H Address Interface Hold Uptime SRTT RTO Q Seq
(sec) (ms) Cnt Num
0 10.1.5.2 Fa0/0 14 02:00:05 40 1000 0 19
1 10.1.3.2 Se0/0/1 13 01:59:59 40 1000 0 14
2 10.1.2.2 Se0/0/0 13 01:59:59 40 1000 0 13
3 10.1.4.2 Se0/1/0 12 01:59:57 40 1000 0 15
fields:
H - the order in which the neighbors were discovered
hold - how long the router will wait for a hello packet
uptime - how long the neigborship has been established
SRTT - smooth round trip timer - the time it takes for a round trip from this router, to neighbor, and back.
SRTT is used to determine how long to wait for a MULTICAST reply.
if a reply isnt received in time, the router switches to UNICASTS
RTO - Retransmission Time Out- is the time EIGRP waits before retransmitting a packet from the retransmission queue
Q - indicates wheter there are oustanding messages in the queue
Seq - indicates the sequence number of the last update from that neighbor. This is used to maintain syncrhonization and avoid duplicate
or out-of-sequence processing of messages
Corp#
show ip route eigrp
172.16.0.0/24 is subnetted, 1 subnets
D 172.16.10.0 [90/28160] via 10.1.5.2, 02:08:04, FastEthernet0/0
D 192.168.10.0/24 [90/2172416] via 10.1.3.2, 02:07:59, Serial0/0/1
[90/2172416] via 10.1.2.2, 02:07:59, Serial0/0/0
D 192.168.20.0/24 [90/2172416] via 10.1.3.2, 02:07:59, Serial0/0/1
[90/2172416] via 10.1.2.2, 02:07:59, Serial0/0/0
D 192.168.30.0/24 [90/2172416] via 10.1.4.2, 02:07:58, Serial0/1/0
D 192.168.40.0/24 [90/2172416] via 10.1.4.2, 02:07:58, Serial0/1/0
Corp#
show ip eigrp interfaces
IP-EIGRP interfaces for process 10
Xmit Queue Mean Pacing Time Multicast Pending
Interface Peers Un/Reliable SRTT Un/Reliable Flow Timer Routes
Vlan 0 0/0 1236 0/10 0 0
Fa0/0 1 0/0 1236 0/10 0 0
Se0/1/0 1 0/0 1236 0/10 0 0
Se0/0/1 1 0/0 1236 0/10 0 0
Se0/0/0 1 0/0 1236 0/10 0 0
Corp#
show ip protocols
Routing Protocol is "eigrp 10 "
Outgoing update filter list for all interfaces is not set
Incoming update filter list for all interfaces is not set
Default networks flagged in outgoing updates
Default networks accepted from incoming updates
Redistributing: eigrp 10
EIGRP-IPv4 Protocol for AS(10)
Metric weight K1=1, K2=0, K3=1, K4=0, K5=0 using K1 bandwidth and K2 delay by default
NSF-aware route hold timer is 240
Router-ID: 10.1.1.1
Topology : 0 (base)
Active Timer: 3 min
Distance: internal 90 external 170
Maximum path: 4
Maximum hopcount 100
Maximum metric variance 1
Automatic Summarization: disabled
Automatic address summarization:
Maximum path: 4
Routing for Networks:
10.0.0.0
Routing Information Sources:
Gateway Distance Last Update
10.1.5.2 90 0
10.1.3.2 90 8936
10.1.4.2 90 9511
10.1.2.2 90 9597
Distance: internal 90 external 170
Routing Protocol is "rip"
Sending updates every 30 seconds, next due in 13 seconds
Invalid after 180 seconds, hold down 180, flushed after 240
Outgoing update filter list for all interfaces is not set
Incoming update filter list for all interfaces is not set
Redistributing: rip
Default version control: send version 2, receive 2
Interface Send Recv Triggered RIP Key-chain
Vlan1 2 2
FastEthernet0/0 2 2
Serial0/0/1 2 2
Serial0/1/0 2 2
Serial0/0/0 2 2
Automatic network summarization is not in effect
Maximum path: 4
Routing for Networks:
10.0.0.0
Passive Interface(s):
Routing Information Sources:
Gateway Distance Last Update
10.1.5.2 120 00:00:05
10.1.3.2 120 00:00:12
10.1.2.2 120 00:00:12
10.1.4.2 120 00:00:17
Distance: (default is 120)
corp#
debug eigrp packet
break into two columns for readability
Observations:
There doesnt appear to be a pattern in the order each router is addressed, except that the TO's and FROM"s are grouped together
The TO messages dont show the destination IP, only the egress local interface
The FROM messages do show the remote IP, as well as the local ingress interface
Corp#
EIGRP: Received HELLO on FastEthernet0/0 nbr 10.1.5.2
AS 10, Flags 0x0, Seq 18/0 idbQ 0/0
hello from R3
Corp#
EIGRP: Received HELLO on Serial0/1/0 nbr 10.1.4.2
AS 10, Flags 0x0, Seq 16/0 idbQ 0/0
hello from R2
Corp#
EIGRP: Received HELLO on Serial0/0/0 nbr 10.1.2.2
AS 10, Flags 0x0, Seq 19/0 idbQ 0/0
hello from R1
------------------------------------------------------------
Corp#
EIGRP: Sending HELLO on Serial0/1/0
AS 10, Flags 0x0, Seq 21/0 idbQ 0/0 iidbQ un/rely 0/0
hello to R2
Corp#
EIGRP: Sending HELLO on FastEthernet0/0
AS 10, Flags 0x0, Seq 21/0 idbQ 0/0 iidbQ un/rely 0/0
hello to R3
Corp#
EIGRP: Sending HELLO on Serial0/0/1
AS 10, Flags 0x0, Seq 21/0 idbQ 0/0 iidbQ un/rely 0/0
hello to R1
Corp#
EIGRP: Sending HELLO on Serial0/0/0
AS 10, Flags 0x0, Seq 21/0 idbQ 0/0 iidbQ un/rely 0/0
hello to R1
Corp#
EIGRP: Sending HELLO on Vlan1
AS 10, Flags 0x0, Seq 21/0 idbQ 0/0 iidbQ un/rely 0/0
hello to switch card (not a router....)
------------------------------------------------------------
Corp#
EIGRP: Received HELLO on Serial0/0/1 nbr 10.1.3.2
AS 10, Flags 0x0, Seq 19/0 idbQ 0/0
hello from R1
Corp#
EIGRP: Received HELLO on FastEthernet0/0 nbr 10.1.5.2
AS 10, Flags 0x0, Seq 18/0 idbQ 0/0
hello from R3
Corp#
EIGRP: Received HELLO on Serial0/0/0 nbr 10.1.2.2
AS 10, Flags 0x0, Seq 19/0 idbQ 0/0
hello from R1
Corp#
EIGRP: Received HELLO on Serial0/1/0 nbr 10.1.4.2
AS 10, Flags 0x0, Seq 16/0 idbQ 0/0
hello from R2
------------------------------------------------------------
Corp#
EIGRP: Sending HELLO on Serial0/1/0
AS 10, Flags 0x0, Seq 21/0 idbQ 0/0 iidbQ un/rely 0/0
hello to R2... no neighbor IP?
Corp#
EIGRP: Sending HELLO on Serial0/0/0
AS 10, Flags 0x0, Seq 21/0 idbQ 0/0 iidbQ un/rely 0/0
hello to R1... no neighbor IP?
Corp#
EIGRP: Sending HELLO on FastEthernet0/0
AS 10, Flags 0x0, Seq 21/0 idbQ 0/0 iidbQ un/rely 0/0
hello to R3... no neighbor IP?
Corp#
EIGRP: Sending HELLO on Serial0/0/1
AS 10, Flags 0x0, Seq 21/0 idbQ 0/0 iidbQ un/rely 0/0
hello to R1
Corp#
EIGRP: Sending HELLO on Vlan1
AS 10, Flags 0x0, Seq 21/0 idbQ 0/0 iidbQ un/rely 0/0
hello to switch card (not a router)
------------------------------------------------------------
OUTPUT CONTINUES IN NEXT COLUMN
Corp#
EIGRP: Received HELLO on Serial0/0/1 nbr 10.1.3.2
AS 10, Flags 0x0, Seq 19/0 idbQ 0/0
hello from R1
Corp#
EIGRP: Received HELLO on FastEthernet0/0 nbr 10.1.5.2
AS 10, Flags 0x0, Seq 18/0 idbQ 0/0
hello from R3
Corp#
EIGRP: Received HELLO on Serial0/0/0 nbr 10.1.2.2
AS 10, Flags 0x0, Seq 19/0 idbQ 0/0
hello from R1
Corp#
EIGRP: Received HELLO on Serial0/1/0 nbr 10.1.4.2
AS 10, Flags 0x0, Seq 16/0 idbQ 0/0
hello from R2
------------------------------------------------------------
Corp#
EIGRP: Sending HELLO on Serial0/1/0
AS 10, Flags 0x0, Seq 21/0 idbQ 0/0 iidbQ un/rely 0/0
hello to R2
Corp#
EIGRP: Sending HELLO on Serial0/0/0
AS 10, Flags 0x0, Seq 21/0 idbQ 0/0 iidbQ un/rely 0/0
hello to R1
Corp#
EIGRP: Sending HELLO on Vlan1
AS 10, Flags 0x0, Seq 21/0 idbQ 0/0 iidbQ un/rely 0/0
hello to Corp switchcard
Corp#
EIGRP: Sending HELLO on Serial0/0/1
AS 10, Flags 0x0, Seq 21/0 idbQ 0/0 iidbQ un/rely 0/0
hello to R1
Corp#
EIGRP: Sending HELLO on FastEthernet0/0
AS 10, Flags 0x0, Seq 21/0 idbQ 0/0 iidbQ un/rely 0/0
hello to R3... no neighbor IP?
------------------------------------------------------------
Corp#
EIGRP: Received HELLO on Serial0/0/1 nbr 10.1.3.2
AS 10, Flags 0x0, Seq 19/0 idbQ 0/0
hello from R1
Corp#
EIGRP: Received HELLO on FastEthernet0/0 nbr 10.1.5.2
AS 10, Flags 0x0, Seq 18/0 idbQ 0/0
hello from R3
Corp#
EIGRP: Received HELLO on Serial0/1/0 nbr 10.1.4.2
AS 10, Flags 0x0, Seq 16/0 idbQ 0/0
hello from R2
Corp#
EIGRP: Received HELLO on Serial0/0/0 nbr 10.1.2.2
AS 10, Flags 0x0, Seq 19/0 idbQ 0/0
hello from R1
------------------------------------------------------------
Corp#
EIGRP: Sending HELLO on Serial0/1/0
AS 10, Flags 0x0, Seq 21/0 idbQ 0/0 iidbQ un/rely 0/0
hello to R2
Corp#
EIGRP: Sending HELLO on Vlan1
AS 10, Flags 0x0, Seq 21/0 idbQ 0/0 iidbQ un/rely 0/0
hello to Corp switchcard
EIGRP: Sending HELLO on Serial0/0/0
AS 10, Flags 0x0, Seq 21/0 idbQ 0/0 iidbQ un/rely 0/0
hello to R1
EIGRP: Sending HELLO on Serial0/0/1
AS 10, Flags 0x0, Seq 21/0 idbQ 0/0 iidbQ un/rely 0/0
hello to R1
Corp#
EIGRP: Sending HELLO on FastEthernet0/0
AS 10, Flags 0x0, Seq 21/0 idbQ 0/0 iidbQ un/rely 0/0
hello to R3
------------------------------------------------------------
Now some videos. To reinforce EIGRP concepts, and lead into OSPF
OSPF - OPEN SHORTEST PATH FIRST
Before enabling OSPF, we'll turn off RIP and EIGRP on all four routers.
Device(config)#
no router eigrp 10
Device(config)#
no router rip
The OSPF configs for the local egress ip address
Corp(config)#
router ospf 132
Corp(config)#
network 10.1.0.0 0.0.255.255 area 0
R1(config)#
router ospf 1
R1(config)#
network 10.1.0.0 0.0.255.255 area 0
R1(config)#
network 192.168.0.0 0.0.255.255 area 0
R2(config)#
router ospf 45678
R2(config)#
network 10.0.0.0 0.0.0.255 area 0
R2(config)#
network 192.168.30.1 0.0.0.0 area 0
R2(config)#
network 192.168.40.1 0.0.0.0 area 0
all 32 bits of the mask are specified for the 192 entries;
these are not network id's, they are HOST id's of the specific interfaces, which are EGRESS interfaces on the router we are configuring
R3(config)#
router ospf 1
R2(config)#
network 10.1.5.2 0.0.0.255 area 0
R2(config)#
network 172.16.10.0 0.0.0.255 area 0
Wildcard Masks
these notes are not intended to be a precise explanation of wlidcard masking, but rather a look into my thought process as I am learning the concept.
resources:
traceroute blog examples
routerjockey blog examples
subnetonline wildcard calculator
Ch 9 Exam Essentials
1. Know EIGRP features
classless (like RipV2 and OSPF)
distance vector
supports IP, IPX, appleTalk, IPV6
supports summaries and discontiguous networks
uses the Diffusing Update Algorithm (DUAL) to maintain route information
uses RTP to communicate with other EIGRP routers
uses the concept of an autonomous system to describe the set of contiguous routers that run the same routing protocol and share routing information
considered CLASSLESS- includes the subnet mask in its route updates
sends traditional distance-vector updates containing info about networks plus the cost of reaching them from the perspective of the advertising router
but not strictly distance-vector. Has link-state characteristics: synchronizes routing tables between neighbors at startup and then sends specific updates only when topology changes.
max hop count of 255 (default is 100)
but hop count is NOT a metric, like in RIP. Hop count is how many routers an EIGRP route update can traverse before being discarded. This limits the size of the AS.
2. Know how to configure EIGRP
the router eigrp [as] command turns EIGRP routing on in the router. Unlike RIPv1, EIGRP uses classless routing. BUT you can still configure as classful.
R1(config)#
router eigrp 10
enters router config mode
R1(config-router)#
network 10.0.0.0
on this router, interfaces that fall within 10.0.0.0 will advertise EIGRP info
3. Know how to verify EIGRP operation
Corp#
show ip
protocols
Corp#
show ip
route
Corp#
show ip
route eigrp
Corp#
show ip
eigrp neighbors
Corp#
show ip
eigrp topology
Corp#
show ip
eigrp interfaces
Corp#
show ip
protocols
info about all active routing protocols
Routing Protocol is "eigrp 10 "
Outgoing update filter list for all interfaces is not set
Incoming update filter list for all interfaces is not set
Default networks flagged in outgoing updates
Default networks accepted from incoming updates
Redistributing: eigrp 10
EIGRP-IPv4 Protocol for AS(10)
Metric weight K1=1, K2=0, K3=1, K4=0, K5=0
NSF-aware route hold timer is 240
Router-ID: 10.1.1.1
Topology : 0 (base)
Active Timer: 3 min
Distance: internal 90 external 170
Maximum path: 4
Maximum hopcount 100
Maximum metric variance 1
Automatic Summarization: disabled
Automatic address summarization:
Maximum path: 4
Routing for Networks:
10.0.0.0
Routing Information Sources:
Gateway Distance Last Update
10.1.2.2 90 200105
10.1.3.2 90 200113
10.1.4.2 90 254351
10.1.5.2 90 303742
Distance: internal 90 external 170
Corp#
show ip
protocols
(continued)
Routing Protocol is "rip"
Sending updates every 30 seconds, next due in 6 seconds
Invalid after 180 seconds, hold down 180, flushed after 240
Outgoing update filter list for all interfaces is not set
Incoming update filter list for all interfaces is not set
Redistributing: rip
Default version control: send version 2, receive 2
Interface Send Recv Triggered RIP Key-chain
Vlan1 2 2
FastEthernet0/0 2 2
Serial0/1/0 2 2
Serial0/0/1 2 2
Serial0/0/0 2 2
Automatic network summarization is not in effect
Maximum path: 4
Routing for Networks:
10.0.0.0
Passive Interface(s):
Routing Information Sources:
Gateway Distance Last Update
10.1.5.2 120 00:00:15
10.1.3.2 120 00:00:01
10.1.2.2 120 00:00:01
10.1.4.2 120 00:00:17
Distance: (default is 120)
Corp#
show ip
route
entire routing table
Codes: L - local, C - connected, S - static, R - RIP, M - mobile, B - BGP
D - EIGRP, EX - EIGRP external, O - OSPF, IA - OSPF inter area
N1 - OSPF NSSA external type 1, N2 - OSPF NSSA external type 2
E1 - OSPF external type 1, E2 - OSPF external type 2, E - EGP
i - IS-IS, L1 - IS-IS level-1, L2 - IS-IS level-2, ia - IS-IS inter area
* - candidate default, U - per-user static route, o - ODR
P - periodic downloaded static route
Gateway of last resort is not set
10.0.0.0/8 is variably subnetted, 10 subnets, 2 masks
C 10.1.1.0/24 is directly connected, Vlan1
L 10.1.1.1/32 is directly connected, Vlan1
C 10.1.2.0/24 is directly connected, Serial0/0/0
L 10.1.2.1/32 is directly connected, Serial0/0/0
C 10.1.3.0/24 is directly connected, Serial0/0/1
L 10.1.3.1/32 is directly connected, Serial0/0/1
C 10.1.4.0/24 is directly connected, Serial0/1/0
L 10.1.4.1/32 is directly connected, Serial0/1/0
C 10.1.5.0/24 is directly connected, FastEthernet0/0
L 10.1.5.1/32 is directly connected, FastEthernet0/0
172.16.0.0/16 is variably subnetted, 2 subnets, 2 masks
R 172.16.0.0/16 [120/1] via 10.1.5.2, 00:00:14, FastEthernet0/0
D 172.16.10.0/24 [90/28160] via 10.1.5.2, 00:07:23, FastEthernet0/0
D 192.168.10.0/24 [90/2172416] via 10.1.3.2, 00:09:13, Serial0/0/1
[90/2172416] via 10.1.2.2, 00:09:13, Serial0/0/0
D 192.168.20.0/24 [90/2172416] via 10.1.3.2, 00:09:13, Serial0/0/1
[90/2172416] via 10.1.2.2, 00:09:13, Serial0/0/0
D 192.168.30.0/24 [90/2172416] via 10.1.4.2, 00:08:59, Serial0/1/0
D 192.168.40.0/24 [90/2172416] via 10.1.4.2, 00:08:59, Serial0/1/0
Shows the entire routing table
Corp#
show ip
eigrp toplogy
all nets the Corp router can see, including on the other side of other routers
IP-EIGRP Topology Table for AS 10/ID(10.1.5.1)
Codes: P - Passive, A - Active, U - Update, Q - Query, R - Reply,
r - Reply status
directly connected via local egress interface
P 10.1.1.0/24, 1 successors, FD is 25625600
via Connected, Vlan1
P 10.1.2.0/24, 1 successors, FD is 2169856
via Connected, Serial0/0/0
P 10.1.3.0/24, 1 successors, FD is 2169856
via Connected, Serial0/0/1
P 10.1.4.0/24, 1 successors, FD is 2169856
via Connected, Serial0/1/0
P 10.1.5.0/24, 1 successors, FD is 28160
via Connected, FastEthernet0/0
remotely connected via remote ingress ip address
P 172.16.10.0/24, 1 successors, FD is 28160
via 10.1.5.2 (28160/25600), FastEthernet0/0
P 192.168.10.0/24, 2 successors, FD is 2172416
via 10.1.3.2 (2172416/28160), Serial0/0/1
via 10.1.2.2 (2172416/28160), Serial0/0/0
P 192.168.20.0/24, 2 successors, FD is 2172416
via 10.1.3.2 (2172416/28160), Serial0/0/1
via 10.1.2.2 (2172416/28160), Serial0/0/0
P 192.168.30.0/24, 1 successors, FD is 2172416
via 10.1.4.2 (2172416/28160), Serial0/1/0
P 192.168.40.0/24, 1 successors, FD is 2172416
via 10.1.4.2 (2172416/28160), Serial0/1/0
Corp#
show ip
eigrp interfaces
local interfaces on Corp, with peer data, 5 total, including VLAN1 (0 peers, no router on this network)
IP-EIGRP interfaces for process 10
Xmit Queue Mean Pacing Time Multicast Pending
Interface Peers Un/Reliable SRTT Un/Reliable Flow Timer Routes
Vlan 0 0/0 1236 0/10 0 0
Fa0/0 1 0/0 1236 0/10 0 0
Se0/0/1 1 0/0 1236 0/10 0 0
Se0/1/0 1 0/0 1236 0/10 0 0
Se0/0/0 1 0/0 1236 0/10 0 0
Corp#
show ip
eigrp neighbors
remote interfaces on the 4 neighboring routers
IP-EIGRP neighbors for process 10
H Address Interface Hold Uptime SRTT RTO Q Seq
(sec) (ms) Cnt Num
0 10.1.2.2 Se0/0/0 14 00:54:33 40 1000 0 58
1 10.1.3.2 Se0/0/1 10 00:54:33 40 1000 0 57
2 10.1.4.2 Se0/1/0 14 00:53:38 40 1000 0 51
3 10.1.5.2 Fa0/0 11 00:52:49 40 1000 0 33
4. Compare OSPF and RIPv1
RIPv1 is distance-vector and supports only classful routing. No VLSM
OSPF is link-state and supports VLSM and classless routing
5. Know how OSPF routers become neighboars and/or adjacent
they become neighbors when they see eachother's hello packets.
area id must match, links must be on the same subnet, hello/dead timers must be the same.
OSPF only shares routes with neigbors who have also established adjacencies. NOT ALL NEIGHBORS become adjacent.
When an OSPF router first receives a hello packet, it verifies that the data in some fields matches its own locally configured information.
Should any of the checked data be different, the hello packet is discarded and not processed. The data fields verified are the Area ID,
Authentication, Network Mask (on broadcast networks), Hello Interval, Router Dead Interval, and Options fields. If this information doesn’t match,
then neighborship is stuck in the down stage.
packetpushers.net
6. Be able to configure single-area OSPF
two commands:
router ospf [process id]
network x.x.x.x y.y.y.y area z
7. Be able to verify the operation of OSPF
Corp#
show ip
protocols
Corp#
show ip
route
Corp#
show ip
ospf
Corp#
show ip
ospf database
Corp#
show ip
ospf interface
Corp#
show ip
ospf neighbor
IOS 15.1
Corp#
show ip
protocols
Routing Protocol is "ospf 132"
Outgoing update filter list for all interfaces is not set
Incoming update filter list for all interfaces is not set
Router ID 10.1.5.1
Number of areas in this router is 1. 1 normal 0 stub 0 nssa
Maximum path: 4
Routing for Networks:
10.1.0.0 0.0.255.255 area 0
Routing Information Sources:
Gateway Distance Last Update
10.1.5.1 110 00:08:51
172.16.10.1 110 00:08:51
192.168.20.1 110 00:12:53
192.168.40.1 110 00:09:35
Distance: (default is 110)
IOS 15.1
Corp#
show ip
route
10.0.0.0/8 is variably subnetted, 10 subnets, 2 masks
C 10.1.1.0/24 is directly connected, Vlan1
L 10.1.1.1/32 is directly connected, Vlan1
C 10.1.2.0/24 is directly connected, Serial0/0/0
L 10.1.2.1/32 is directly connected, Serial0/0/0
C 10.1.3.0/24 is directly connected, Serial0/0/1
L 10.1.3.1/32 is directly connected, Serial0/0/1
C 10.1.4.0/24 is directly connected, Serial0/1/0
L 10.1.4.1/32 is directly connected, Serial0/1/0
C 10.1.5.0/24 is directly connected, FastEthernet0/0
L 10.1.5.1/32 is directly connected, FastEthernet0/0
172.16.0.0/24 is subnetted, 1 subnets
O 172.16.10.0/24 [110/10] via 10.1.5.2, 00:09:09, FastEthernet0/0
O 192.168.10.0/24 [110/65] via 10.1.2.2, 00:13:11, Serial0/0/0
O 192.168.20.0/24 [110/65] via 10.1.2.2, 00:13:01, Serial0/0/0
O 192.168.30.0/24 [110/65] via 10.1.4.2, 00:09:54, Serial0/1/0
O 192.168.40.0/24 [110/65] via 10.1.4.2, 00:09:54, Serial0/1/0
IOS 15.1
Corp#
show ip
ospf
Routing Process "ospf 132" with ID 10.1.5.1
Supports only single TOS(TOS0) routes
Supports opaque LSA
SPF schedule delay 5 secs, Hold time between two SPFs 10 secs
Minimum LSA interval 5 secs. Minimum LSA arrival 1 secs
Number of external LSA 0. Checksum Sum 0x000000
Number of opaque AS LSA 0. Checksum Sum 0x000000
Number of DCbitless external and opaque AS LSA 0
Number of DoNotAge external and opaque AS LSA 0
Number of areas in this router is 1. 1 normal 0 stub 0 nssa
External flood list length 0
Area BACKBONE(0)
Number of interfaces in this area is 5
Area has no authentication
SPF algorithm executed 7 times
Area ranges are
Number of LSA 5. Checksum Sum 0x034486
Number of opaque link LSA 0. Checksum Sum 0x000000
Number of DCbitless LSA 0
Number of indication LSA 0
Number of DoNotAge LSA 0
Flood list length 0
IOS 15.1
Corp#
show ip
ospf database
OSPF Router with ID (10.1.5.1) (Process ID 132)
Router Link States (Area 0)
Link ID ADV Router Age Seq# Checksum Link count
192.168.20.1 192.168.20.1 854 0x80000006 0x00ae08 6
192.168.40.1 192.168.40.1 656 0x80000004 0x006bc6 4
10.1.5.1 10.1.5.1 612 0x8000000f 0x00ab77 8
172.16.10.1 172.16.10.1 612 0x80000003 0x00b30d 2
Net Link States (Area 0)
Link ID ADV Router Age Seq# Checksum
10.1.5.1 10.1.5.1 612 0x80000001 0x00cc34
ADV Router aka RID/Router ID, the highest IP address on the router
we are seeing three connected routers + our own router (Corp at 10.1.5.1)
IOS 15.1
Corp#
show ip
ospf interface
Vlan1 is up, line protocol is up
Internet address is 10.1.1.1/24, Area 0
Process ID 132, Router ID 10.1.5.1, Network Type BROADCAST, Cost: 1
Transmit Delay is 1 sec, State DR, Priority 1
Designated Router (ID) 10.1.5.1, Interface address 10.1.1.1
No backup designated router on this network
Timer intervals configured, Hello 10, Dead 40, Wait 40, Retransmit 5
Hello due in 00:00:08
Index 1/1, flood queue length 0
Next 0x0(0)/0x0(0)
Last flood scan length is 1, maximum is 1
Last flood scan time is 0 msec, maximum is 0 msec
Neighbor Count is 0, Adjacent neighbor count is 0
Suppress hello for 0 neighbor(s)
FastEthernet0/0 is up, line protocol is up
Internet address is 10.1.5.1/24, Area 0
Process ID 132, Router ID 10.1.5.1, Network Type BROADCAST, Cost: 1
Transmit Delay is 1 sec, State DR, Priority 1
Designated Router (ID) 10.1.5.1, Interface address 10.1.5.1
Backup Designated Router (ID) 172.16.10.1, Interface address 10.1.5.2
Timer intervals configured, Hello 10, Dead 40, Wait 40, Retransmit 5
Hello due in 00:00:07
Index 2/2, flood queue length 0
Next 0x0(0)/0x0(0)
Last flood scan length is 1, maximum is 1
Last flood scan time is 0 msec, maximum is 0 msec
Neighbor Count is 1, Adjacent neighbor count is 1
Adjacent with neighbor 172.16.10.1 (Backup Designated Router)
Suppress hello for 0 neighbor(s)
Serial0/0/1 is up, line protocol is up
Internet address is 10.1.3.1/24, Area 0
Process ID 132, Router ID 10.1.5.1, Network Type POINT-TO-POINT, Cost: 64
Transmit Delay is 1 sec, State POINT-TO-POINT,
Timer intervals configured, Hello 10, Dead 40, Wait 40, Retransmit 5
Hello due in 00:00:07
Index 3/3, flood queue length 0
Next 0x0(0)/0x0(0)
Last flood scan length is 1, maximum is 1
Last flood scan time is 0 msec, maximum is 0 msec
Neighbor Count is 1 , Adjacent neighbor count is 1
Adjacent with neighbor 192.168.20.1
Suppress hello for 0 neighbor(s)
Serial0/1/0 is up, line protocol is up
Internet address is 10.1.4.1/24, Area 0
Process ID 132, Router ID 10.1.5.1, Network Type POINT-TO-POINT, Cost: 64
Transmit Delay is 1 sec, State POINT-TO-POINT,
Timer intervals configured, Hello 10, Dead 40, Wait 40, Retransmit 5
Hello due in 00:00:07
Index 4/4, flood queue length 0
Next 0x0(0)/0x0(0)
Last flood scan length is 1, maximum is 1
Last flood scan time is 0 msec, maximum is 0 msec
Neighbor Count is 1 , Adjacent neighbor count is 1
Adjacent with neighbor 192.168.40.1
Suppress hello for 0 neighbor(s)
Serial0/0/0 is up, line protocol is up
Internet address is 10.1.2.1/24, Area 0
Process ID 132, Router ID 10.1.5.1, Network Type POINT-TO-POINT, Cost: 64
Transmit Delay is 1 sec, State POINT-TO-POINT,
Timer intervals configured, Hello 10, Dead 40, Wait 40, Retransmit 5
Hello due in 00:00:07
Index 5/5, flood queue length 0
Next 0x0(0)/0x0(0)
Last flood scan length is 1, maximum is 1
Last flood scan time is 0 msec, maximum is 0 msec
Neighbor Count is 1 , Adjacent neighbor count is 1
Adjacent with neighbor 192.168.20.1
Suppress hello for 0 neighbor(s)
IOS 15.1
Corp#
show ip
ospf neighbor
Neighbor ID Pri State Dead Time Address Interface
192.168.20.1 0 FULL/ - 00:00:31 10.1.3.2 Serial0/0/1
192.168.40.1 0 FULL/ - 00:00:33 10.1.4.2 Serial0/1/0
192.168.20.1 0 FULL/ - 00:00:31 10.1.2.2 Serial0/0/0
172.16.10.1 1 FULL/BDR 00:00:32 10.1.5.2 FastEthernet0/0
Flashcards
Chapter 9 Written Lab 9.0
1. What four routed protocols are supported by EIGRP?
IPX, IPv4, IPv6, AppleTalk
2. When is redistribution required for EIGRP?
when there are multiple autonomous systems
redistribution is required when more than one EIGRP session or process is running and they are identified with different ASNs.
redistribution shares toplogy information between EIGRP sessions
3. What command would be used to enable EIGRP with an autonmous system number of 300?
router eigrp 300
4. What command will tell EIGRP that it is connected to network 172.10.0.0?
network 172.10.0.0
5. What type of EIGRP interface will neither send nor receive Hello packets?
passive-interface s0/0
6. Write the command that will enable OSPF process 101 on a router
router ospf 101
7. Write the command that will display details of all OSFP routing processes enabled on a router
show ip ospf
8. Write the command that will display interface-specific OSPF information
show ip ospf interface
9. Write the command that will display all OSPF neighbors
show ip ospf neighbor
10. Write the command that will display all different OSPF route types that are currently known by the router
show ip route ospf
Chapter 9 Hands-On Labs
Build the network and configure interfaces
LabA(config)#
int f0/0
LabA(config-if)#
ip addr 172.16.10.1 255.255.255.0
LabA(config-if)#
no shut
LabB(config)#
int f0/0
LabB(config-if)#
ip addr 172.16.10.2 255.255.255.0
LabB(config-if)#
no shut
LabB(config-if)#
int s0/0/0
LabB(config-if)#
ip addr 172.16.20.1 255.255.255.0
LabB(config-if)#
no shut
LabC(config)#
int f0/0
LabC(config-if)#
ip addr 172.16.30.1 255.255.255.0
LabC(config-if)#
no shut
LabC(config-if)#
int s0/0/0
LabC(config-if)#
ip addr 172.16.20.2 255.255.255.0
LabC(config-if)#
no shut
LabC(config-if)#
int s0/0/1
LabC(config-if)#
ip addr 172.16.40.1 255.255.255.0
LabC(config-if)#
no shut
LabD(config)#
int s0/0/0
LabD(config-if)#
ip addr 172.16.40.2 255.255.255.0
LabD(config-if)#
no shut
LabD(config-if)#
int f0/0
LabD(config-if)#
ip addr 172.16.50.1 255.255.255.0
LabD(config-if)#
no shut
9.1 - Configure and Verfiy EIGRP
configure EIGRP on all 4 routers and observe results
LabA
LabA(config)#
router eigrp 100
LabA(config-router)#
net 172.16.0.0
[no output]
LabA#
show ip eigrp neighbors
IP-EIGRP neighbors for process 100
LabA#
show ip eigrp topology
IP-EIGRP Topology Table for AS 100/ID(172.16.10.1)
Codes: P - Passive, A - Active, U - Update, Q - Query, R - Reply,
r - Reply status
P 172.16.10.0/24, 1 successors, FD is 28160
via Connected, FastEthernet0/0
LabA#
show ip eigrp interfaces
IP-EIGRP interfaces for process 100
Xmit Queue Mean Pacing Time Multicast Pending
Interface Peers Un/Reliable SRTT Un/Reliable Flow Timer Routes
Fa0/0 0 0/0 1236 0/10 0 0
no neighbors at this point since EIGRP is only active on this router. One successor AKA route, which is the connection out of this router.
But note that we have no information about what's on the other side of that link
LabB
LabB(config)#
router eigrp 100
LabB(config-router)#
net 172.16.0.0
%DUAL-5-NBRCHANGE: IP-EIGRP 100:
Neighbor 172.16.10.1 (FastEthernet0/0) is up: new adjacency
LabB#
show ip eigrp neighbors
IP-EIGRP neighbors for process 100
H Address Interface Hold Uptime SRTT RTO Q Seq
(sec) (ms) Cnt Num
0 172.16.10.1 Fa0/0 12 00:00:14 40 1000 0 1
LabB#
show ip eigrp topology
IP-EIGRP Topology Table for AS 100/ID(172.16.20.1)
Codes: P - Passive, A - Active, U - Update, Q - Query, R - Reply,
r - Reply status
P 172.16.10.0/24, 1 successors, FD is 28160
via Connected, FastEthernet0/0
P 172.16.20.0/24, 1 successors, FD is 2169856
via Connected, Serial0/0/0
LabB#
show ip eigrp interfaces
IP-EIGRP interfaces for process 100
Xmit Queue Mean Pacing Time Multicast Pending
Interface Peers Un/Reliable SRTT Un/Reliable Flow Timer Routes
Fa0/0 1 0/0 1236 0/10 0 0
Se0/0/0 0 0/0 1236 0/10 0 0
We can see a neighbor at .1
We now have two paths out of this router. Left to neighbor. Exit at right is available as successor(route), but again we have no info about
what is on the other side, since that router has no EIGRP yet (s0/0/0 has no peers, but is an EIGRP interface)
LabC
LabC(config)#
router eigrp 100
LabC(config-router)#
net 172.16.0.0
%DUAL-5-NBRCHANGE: IP-EIGRP 100:
Neighbor 172.16.20.1 (Serial0/0/0) is up: new adjacency
LabC#
show ip eigrp neighbors
IP-EIGRP neighbors for process 100
H Address Interface Hold Uptime SRTT RTO Q Seq
(sec) (ms) Cnt Num
0 172.16.20.1 Se0/0/0 12 00:00:25 40 1000 0 8
LabC#
show ip eigrp toplogy
IP-EIGRP Topology Table for AS 100/ID(172.16.40.1)
Codes: P - Passive, A - Active, U - Update, Q - Query, R - Reply,
r - Reply status
P 172.16.10.0/24, 1 successors, FD is 2172416
via 172.16.20.1 (2172416/28160), Serial0/0/0
P 172.16.20.0/24, 1 successors, FD is 2169856
via Connected, Serial0/0/0
P 172.16.30.0/24, 1 successors, FD is 28160
via Connected, FastEthernet0/0
P 172.16.40.0/24, 1 successors, FD is 2169856
via Connected, Serial0/0/1
LabC#
show ip eigrp interfaces
IP-EIGRP interfaces for process 100
Xmit Queue Mean Pacing Time Multicast Pending
Interface Peers Un/Reliable SRTT Un/Reliable Flow Timer Routes
Fa0/0 0 0/0 1236 0/10 0 0
Se0/0/0 1 0/0 1236 0/10 0 0
Se0/0/1 0 0/0 1236 0/10 0 0
.1 router B interface is now a neighbor.
LabC topology shows the 3 direct connected networks AND the network on the other side of LabB since LabB is our EIGRP neighbor
3 eigrp interfaces:
Fa0/0 is ours at LabC- no peers bc there is no eigrp router on the other end
s0/0/0 is our interface out left to LabB which is an EIGRP peer
s0/0/1 is our interface out right which does not see an EIGRP peer but does put that net 172.16.40.0 in our topology
LabD
LabD(config)#
router eigrp 100
LabD(config-router)#
net 172.16.0.0
%DUAL-5-NBRCHANGE: IP-EIGRP 100:
Neighbor 172.16.40.1 (Serial0/0/0) is up: new adjacency
LabD#
show ip eigrp neighbors
IP-EIGRP neighbors for process 100
H Address Interface Hold Uptime SRTT RTO Q Seq
(sec) (ms) Cnt Num
0 172.16.40.1 Se0/0/0 11 00:00:14 40 1000 0 6
LabD#
show ip eigrp topology
IP-EIGRP Topology Table for AS 100/ID(172.16.50.1)
Codes: P - Passive, A - Active, U - Update, Q - Query, R - Reply,
r - Reply status
P 172.16.10.0/24, 1 successors, FD is 2684416
via 172.16.40.1 (2684416/2172416), Serial0/0/0
P 172.16.20.0/24, 1 successors, FD is 2681856
via 172.16.40.1 (2681856/2169856), Serial0/0/0
P 172.16.30.0/24, 1 successors, FD is 2172416
via 172.16.40.1 (2172416/28160), Serial0/0/0
P 172.16.40.0/24, 1 successors, FD is 2169856
via Connected, Serial0/0/0
P 172.16.50.0/24, 1 successors, FD is 28160
via Connected, FastEthernet0/0
LabD#
show ip eigrp interfaces
IP-EIGRP interfaces for process 100
Xmit Queue Mean Pacing Time Multicast Pending
Interface Peers Un/Reliable SRTT Un/Reliable Flow Timer Routes
Fa0/0 0 0/0 1236 0/10 0 0
Se0/0/0 1 0/0 1236 0/10 0 0
LabC to our left is now a neighbor at 172.16.40.1
toplogy shows a route out to the right (no router on that end)
a route to the left to LabC .40.0
the .10.0, .20.0, and .30.0 networks via info from LabC
2 eigrp interfaces-
fa0/0 out to the right
s0/0/0 out left to LabC
Time to remove EIGRP from all four routers to prepare for the OSPF lab next,
since EIGRP has a lower AD than OSPF
LabA(config)#
no router eigrp 100
LabB(config)#
no router eigrp 100
LabC(config)#
no router eigrp 100
LabD(config)#
no router eigrp 100
9.2 - Enabling the OSPF Process
9.3 - Configuring OSPF Interfaces
9.4 - Verifying OSPF Operation
LabA
LabA(config)#
router ospf 100
LabA(config-router)#
net 172.16.10.1 0.0.0.0 area 0
[no output]
LabA#
show ip ospf neighbor
[no output]
LabA#
show ip ospf database
OSPF Router with ID (172.16.10.1) (Process ID 100)
Router Link States (Area 0)
Link ID ADV Router Age Seq# Checksum Link count
172.16.10.1 172.16.10.1 44 0x80000001 0x00b24b 1
LabA#
show ip ospf interface
FastEthernet0/0 is up, line protocol is up
Internet address is 172.16.10.1/24, Area 0
Process ID 100, Router ID 172.16.10.1, Network Type BROADCAST, Cost: 1
Transmit Delay is 1 sec, State DR, Priority 1
Designated Router (ID) 172.16.10.1, Interface address 172.16.10.1
No backup designated router on this network
Timer intervals configured, Hello 10, Dead 40, Wait 40, Retransmit 5
Hello due in 00:00:08
Index 1/1, flood queue length 0
Next 0x0(0)/0x0(0)
Last flood scan length is 1, maximum is 1
Last flood scan time is 0 msec, maximum is 0 msec
Neighbor Count is 0, Adjacent neighbor count is 0
Suppress hello for 0 neighbor(s)
we're including this router's interface 172.16.10.1 in our ospf area 0
fa0/0 now registers as an ospf interface
the ospf database includes data about this link only.... LabA is counting itself(10.1) as ADVERTISTING router?
the designated router is .1 LabA
LabB
LabB(config)#
router ospf 101
LabB(config-router)#
net 172.16.10.2 0.0.0.0 area 0
LabB(config-router)#
net 172.16.20.1 0.0.0.0 area 0
01:26:36: %OSPF-5-ADJCHG: Process 101, Nbr 172.16.10.1
on FastEthernet0/0 from LOADING to FULL, Loading Done
LabB#
show ip ospf neighbor
Neighbor ID Pri State Dead Time Address Interface
172.16.10.1 1 FULL/DR 00:00:33 172.16.10.1
LabB#
show ip ospf database
OSPF Router with ID (172.16.20.1) (Process ID 101)
Router Link States (Area 0)
Link ID ADV Router Age Seq# Checksum Link count
172.16.10.1 172.16.10.1 145 0x80000002 0x0067cd 1
172.16.20.1 172.16.20.1 32 0x80000003 0x006e8f 2
Net Link States (Area 0)
Link ID ADV Router Age Seq# Checksum
172.16.10.1 172.16.10.1 145 0x80000001 0x00953d
LabB#
show ip ospf interface
FastEthernet0/0 is up, line protocol is up
Internet address is 172.16.10.2/24, Area 0
Process ID 101, Router ID 172.16.20.1, Network Type BROADCAST, Cost: 1
Transmit Delay is 1 sec, State BDR, Priority 1
Designated Router (ID) 172.16.10.1, Interface address 172.16.10.1
Backup Designated Router (ID) 172.16.20.1, Interface address 172.16.10.2
Timer intervals configured, Hello 10, Dead 40, Wait 40, Retransmit 5
Hello due in 00:00:03
Index 1/1, flood queue length 0
Next 0x0(0)/0x0(0)
Last flood scan length is 1, maximum is 1
Last flood scan time is 0 msec, maximum is 0 msec
Neighbor Count is 1, Adjacent neighbor count is 1
Adjacent with neighbor 172.16.10.1 (Designated Router)
Suppress hello for 0 neighbor(s)
Serial0/0/0 is up, line protocol is up
Internet address is 172.16.20.1/24, Area 0
Process ID 101, Router ID 172.16.20.1, Network Type POINT-TO-POINT, Cost: 64
Transmit Delay is 1 sec, State POINT-TO-POINT,
Timer intervals configured, Hello 10, Dead 40, Wait 40, Retransmit 5
Hello due in 00:00:04
Index 2/2, flood queue length 0
Next 0x0(0)/0x0(0)
Last flood scan length is 1, maximum is 1
Last flood scan time is 0 msec, maximum is 0 msec
Suppress hello for 0 neighbor(s)
We've include the two interfaces on this router in the OSPF area
and can now see Router A's interface 10.1 to the left as a neighbor in the area
the "OSPF Database" now shows two links 20.1(local) and 10.1(neighbor) as 'router link states'.
"ADV Router" means advertising router for the two links. The link address is used as the advertising router.
database shows "Net Link States" category with one entry- 172.16.10.1 which is the address of neighbor router to our left
we have two local OSPF interfaces- f0/0 and s0/0/0
LabC
LabC(config)#
router ospf 102
LabC(config-router)#
net 172.16.20.2 0.0.0.0 area 0
LabC(config-router)#
net 172.16.30.1 0.0.0.0 area 0
LabC(config-router)#
net 172.16.40.1 0.0.0.0 area 0
01:33:54: %OSPF-5-ADJCHG: Process 102, Nbr 172.16.20.1
on Serial0/0/0 from LOADING to FULL, Loading Done
LabC#
show ip ospf neighbor
Neighbor ID Pri State Dead Time Address Interface
172.16.20.1 0 FULL/ - 00:00:30 172.16.20.1 Serial0/0/0
LabC#
show ip ospf database
OSPF Router with ID (172.16.40.1) (Process ID 102)
Router Link States (Area 0)
Link ID ADV Router Age Seq# Checksum Link count
172.16.10.1 172.16.10.1 542 0x80000002 0x0067cd 1
172.16.20.1 172.16.20.1 90 0x80000004 0x00a551 3
172.16.40.1 172.16.40.1 37 0x80000004 0x00e47c 4
Net Link States (Area 0)
Link ID ADV Router Age Seq# Checksum
172.16.10.1 172.16.10.1 542 0x80000001 0x00953d
LabC#
show ip ospf interface
Serial0/0/0 is up, line protocol is up
Internet address is 172.16.20.2/24, Area 0
Process ID 102, Router ID 172.16.40.1, Network Type POINT-TO-POINT, Cost: 64
Transmit Delay is 1 sec, State POINT-TO-POINT,
Timer intervals configured, Hello 10, Dead 40, Wait 40, Retransmit 5
Hello due in 00:00:01
Index 1/1, flood queue length 0
Next 0x0(0)/0x0(0)
Last flood scan length is 1, maximum is 1
Last flood scan time is 0 msec, maximum is 0 msec
Neighbor Count is 1 , Adjacent neighbor count is 1
Adjacent with neighbor 172.16.20.1
Suppress hello for 0 neighbor(s)
FastEthernet0/0 is up, line protocol is up
Internet address is 172.16.30.1/24, Area 0
Process ID 102, Router ID 172.16.40.1, Network Type BROADCAST, Cost: 1
Transmit Delay is 1 sec, State DR, Priority 1
Designated Router (ID) 172.16.40.1, Interface address 172.16.30.1
No backup designated router on this network
Timer intervals configured, Hello 10, Dead 40, Wait 40, Retransmit 5
Hello due in 00:00:02
Index 2/2, flood queue length 0
Next 0x0(0)/0x0(0)
Last flood scan length is 1, maximum is 1
Last flood scan time is 0 msec, maximum is 0 msec
Neighbor Count is 0, Adjacent neighbor count is 0
Suppress hello for 0 neighbor(s)
Serial0/0/1 is up, line protocol is up
Internet address is 172.16.40.1/24, Area 0
Process ID 102, Router ID 172.16.40.1, Network Type POINT-TO-POINT, Cost: 64
Transmit Delay is 1 sec, State POINT-TO-POINT,
Timer intervals configured, Hello 10, Dead 40, Wait 40, Retransmit 5
Hello due in 00:00:08
Index 3/3, flood queue length 0
Next 0x0(0)/0x0(0)
Last flood scan length is 1, maximum is 1
Last flood scan time is 0 msec, maximum is 0 msec
Suppress hello for 0 neighbor(s)
we include the three nets conneted to labC in the area.. 20.0, 30.0, and 40.0
link to our left, 20.1 is visible as "Neighbor"
OSPF Database-
Router Link States are
10.1(Router A)
20.1(Router B)
40.1(Router C)(This router)
Net Link States
10.1(Router A)... why does only Router A show here?
Reference- router link state vs net link state
Router Link States are type 1 LSAs. It lists all the routers in the area and the number of interfaces. 40.1 has 4 interfaces
Net Link States are the multi-access networks (Type 2 LSAs). The ADV (advertising router) is the DR.
LabD
LabD(config)#
router ospf 103
LabD(config-router)#
net 172.16.40.2 0.0.0.0 area 0
LabD(config-router)#
net 172.16.50.1 0.0.0.0 area 0
01:37:11: %OSPF-5-ADJCHG: Process 103, Nbr 172.16.40.1
on Serial0/0/0 from LOADING to FULL, Loading Done
LabD#
show ip ospf neighbor
Neighbor ID Pri State Dead Time Address Interface
172.16.40.1 0 FULL/ - 00:00:32 172.16.40.1 Serial0/0/0
LabD#
show ip ospf database
OSPF Router with ID (172.16.50.1) (Process ID 103)
Router Link States (Area 0)
Link ID ADV Router Age Seq# Checksum Link count
172.16.10.1 172.16.10.1 785 0x80000002 0x0067cd 1
172.16.20.1 172.16.20.1 333 0x80000004 0x00a551 3
172.16.40.1 172.16.40.1 111 0x80000005 0x00013b 5
172.16.50.1 172.16.50.1 53 0x80000003 0x001023 3
Net Link States (Area 0)
Link ID ADV Router Age Seq# Checksum
172.16.10.1 172.16.10.1 785 0x80000001 0x00953d
LabD#
show ip ospf interface
Serial0/0/0 is up, line protocol is up
Internet address is 172.16.40.2/24, Area 0
Process ID 103, Router ID 172.16.50.1, Network Type POINT-TO-POINT, Cost: 64
Transmit Delay is 1 sec, State POINT-TO-POINT,
Timer intervals configured, Hello 10, Dead 40, Wait 40, Retransmit 5
Hello due in 00:00:01
Index 1/1, flood queue length 0
Next 0x0(0)/0x0(0)
Last flood scan length is 1, maximum is 1
Last flood scan time is 0 msec, maximum is 0 msec
Neighbor Count is 1 , Adjacent neighbor count is 1
Adjacent with neighbor 172.16.40.1
Suppress hello for 0 neighbor(s)
FastEthernet0/0 is up, line protocol is up
Internet address is 172.16.50.1/24, Area 0
Process ID 103, Router ID 172.16.50.1, Network Type BROADCAST, Cost: 1
Transmit Delay is 1 sec, State WAITING, Priority 1
No designated router on this network
No backup designated router on this network
Timer intervals configured, Hello 10, Dead 40, Wait 40, Retransmit 5
Hello due in 00:00:04
Index 2/2, flood queue length 0
Next 0x0(0)/0x0(0)
Last flood scan length is 1, maximum is 1
Last flood scan time is 0 msec, maximum is 0 msec
Neighbor Count is 0, Adjacent neighbor count is 0
Suppress hello for 0 neighbor(s)
observations
the OSPF databases now match across all 4 routers.
NOTE that this is a database of routers, identified by
router ID. It is not a topology that lists routers AND routes,
like in the "equivalent" eigrp command.show eigrp topology
----------------------------------------------------------------------------------
PAUSE- a tale of a misconfigured network
After a 9 month hiatus, I am reviewing this book and have made it back to Chapter 9. I'm studing this webpage, working thorough the OSPF configurations
described above, and I get stuck on the concept of "link count" under "Router Link States" found in the output of show ip ospf database
The structure of the notes above is helpful, because I was tracking the state of each router BEFORE i made changes to the subsquent router. But just to be sure,
today I decided to recreate the topology, then configure each router one at a time, noting the results as I went.
And I ran into some problems.
Here is the original topology:
And today's recreated toplogy:
After replicating the toplogy and programming the IP addresses on each router, I started on configurations, just like before:
LabA
LabA(config)#
router ospf 100
LabA(config-router)#
net 172.16.10.1 0.0.0.0 area 0
[no output]
LabA#
show ip ospf neighbor
[no output]
LabA#
show ip ospf database
OSPF Router with ID (172.16.10.1) (Process ID 100)
Router Link States (Area 0)
Link ID ADV Router Age Seq# Checksum Link count
172.16.10.1 172.16.10.1 44 0x80000001 0x00b24b 1
LabA#
show ip ospf interface
FastEthernet0/0 is up, line protocol is up
Internet address is 172.16.10.1/24, Area 0
Process ID 100, Router ID 172.16.10.1, Network Type BROADCAST, Cost: 1
Transmit Delay is 1 sec, State DR, Priority 1
Designated Router (ID) 172.16.10.1, Interface address 172.16.10.1
No backup designated router on this network
Timer intervals configured, Hello 10, Dead 40, Wait 40, Retransmit 5
Hello due in 00:00:08
Index 1/1, flood queue length 0
Next 0x0(0)/0x0(0)
Last flood scan length is 1, maximum is 1
Last flood scan time is 0 msec, maximum is 0 msec
Neighbor Count is 0, Adjacent neighbor count is 0
Suppress hello for 0 neighbor(s)
good so far.... On to LabB router
LabB
LabB(config)#
router ospf 101
LabB(config-router)#
net 172.16.10.2 0.0.0.0 area 0
LabB(config-router)#
net 172.16.20.1 0.0.0.0 area 0
01:26:36: %OSPF-5-ADJCHG: Process 101, Nbr 172.16.10.1
on FastEthernet0/0 from LOADING to FULL, Loading Done
LabB#
show ip ospf neighbor
Neighbor ID Pri State Dead Time Address Interface
172.16.10.1 1 FULL/DR 00:00:33 172.16.10.1
LabB#
show ip ospf database
OSPF Router with ID (172.16.20.1) (Process ID 101)
Router Link States (Area 0)
Link ID ADV Router Age Seq# Checksum Link count
172.16.10.1 172.16.10.1 145 0x80000002 0x0067cd 1
172.16.20.1 172.16.20.1 32 0x80000003 0x006e8f 2
Net Link States (Area 0)
Link ID ADV Router Age Seq# Checksum
172.16.10.1 172.16.10.1 145 0x80000001 0x00953d
LabB#
show ip ospf interface
FastEthernet0/0 is up, line protocol is up
Internet address is 172.16.10.2/24, Area 0
Process ID 101, Router ID 172.16.20.1, Network Type BROADCAST, Cost: 1
Transmit Delay is 1 sec, State BDR, Priority 1
Designated Router (ID) 172.16.10.1, Interface address 172.16.10.1
Backup Designated Router (ID) 172.16.20.1, Interface address 172.16.10.2
Timer intervals configured, Hello 10, Dead 40, Wait 40, Retransmit 5
Hello due in 00:00:03
Index 1/1, flood queue length 0
Next 0x0(0)/0x0(0)
Last flood scan length is 1, maximum is 1
Last flood scan time is 0 msec, maximum is 0 msec
Neighbor Count is 1, Adjacent neighbor count is 1
Adjacent with neighbor 172.16.10.1 (Designated Router)
Suppress hello for 0 neighbor(s)
Serial0/0/0 is up, line protocol is up
Internet address is 172.16.20.1/24, Area 0
Process ID 101, Router ID 172.16.20.1, Network Type POINT-TO-POINT, Cost: 64
Transmit Delay is 1 sec, State POINT-TO-POINT,
Timer intervals configured, Hello 10, Dead 40, Wait 40, Retransmit 5
Hello due in 00:00:04
Index 2/2, flood queue length 0
Next 0x0(0)/0x0(0)
Last flood scan length is 1, maximum is 1
Last flood scan time is 0 msec, maximum is 0 msec
Suppress hello for 0 neighbor(s)
still looks good; same as before.... On to LabC router
LabC
LabC(config)#
router ospf 102
LabC(config-router)#
net 172.16.20.2 0.0.0.0 area 0
LabC(config-router)#
net 172.16.30.1 0.0.0.0 area 0
LabC(config-router)#
net 172.16.40.1 0.0.0.0 area 0
01:33:54: %OSPF-5-ADJCHG: Process 102, Nbr 172.16.20.1
on Serial0/0/0 from LOADING to FULL, Loading Done
LabC#
show ip ospf neighbor
[no output]
And here is where I ran into trouble. The show ip ospf neighbor command returns nothing. How can
that be?
After awhile I realized it is due to a misconfiguration in the topology.
For Lab C, I programmed the interfaces as follows:
LabC(config)#
int f0/0
LabC(config-if)#
ip addr 172.16.30.1 255.255.255.0
LabC(config-if)#
no shut
LabC(config-if)#
int s0/0/0
LabC(config-if)#
ip addr 172.16.20.2 255.255.255.0
LabC(config-if)#
no shut
LabC(config-if)#
int s0/0/1
LabC(config-if)#
ip addr 172.16.40.1 255.255.255.0
LabC(config-if)#
no shut
and again here is the topology for that router:
but here is what it SHOULD HAVE looked like (as it did the first time I built it)
S0/0/0 and S0/0/1 are swapped. When I gave the IP 172.16.20.2 to s/0/0/0, thinking that was the interface on the left side
which faces Lab B, I was actually giving 172.16.20.2 to the right side, facing LabC (which has no OSPF configs yet.)
Since the left side got got the IP intended for the right side which was 172.16.40.1
the inverse also occured-
the right side got the IP intended for the left which was 172.16.20.2
LabC left side should have been
s0/0/0 with 20.2
and LabC right side should have been
s0/0/1 with 40.1
The correct IPs were mapped to the correct interfaces. But the mistake happened before I even programmed them.
When I made the connections from LabB to LabC and from LabD to LabC, I plugged then into the wrong ports.
Interestingly.. not only is this causing OSPF to not see B as a neighbor from C.. but B and C cannot ping eachother either.
@B the config is 172.16.20.1/24 @ S0/0/0
@C the config is 172.16.40.1/24 @ S/0/0/1
meaning they are not even on the same network! But the system is not throwing any errors or bringing it to my attention.
It just fails to connect.
To correct the issue, I simply deleted those two links and re-created them. Worth noting, I used the auto select cable here,
which does not ask which interface you want to use when attaching. Earlier I must have plugged the right side first, and
auto select plugged into 0/0/0.
This time I plugged into left side first.
Now LabC OSPF data is reading out correctly...
LabC
LabC(config)#
router ospf 102
LabC(config-router)#
net 172.16.20.2 0.0.0.0 area 0
LabC(config-router)#
net 172.16.30.1 0.0.0.0 area 0
LabC(config-router)#
net 172.16.40.1 0.0.0.0 area 0
01:33:54: %OSPF-5-ADJCHG: Process 102, Nbr 172.16.20.1
on Serial0/0/0 from LOADING to FULL, Loading Done
LabC#
show ip ospf neighbor
Neighbor ID Pri State Dead Time Address Interface
172.16.20.1 0 FULL/ - 00:00:30 172.16.20.1 Serial0/0/0
LabC#
show ip ospf database
OSPF Router with ID (172.16.40.1) (Process ID 102)
Router Link States (Area 0)
Link ID ADV Router Age Seq# Checksum Link count
172.16.10.1 172.16.10.1 542 0x80000002 0x0067cd 1
172.16.20.1 172.16.20.1 90 0x80000004 0x00a551 3
172.16.40.1 172.16.40.1 37 0x80000004 0x00e47c 4
Net Link States (Area 0)
Link ID ADV Router Age Seq# Checksum
172.16.10.1 172.16.10.1 542 0x80000001 0x00953d
LabC#
show ip ospf interface
Serial0/0/0 is up, line protocol is up
Internet address is 172.16.20.2/24, Area 0
Process ID 102, Router ID 172.16.40.1, Network Type POINT-TO-POINT, Cost: 64
Transmit Delay is 1 sec, State POINT-TO-POINT,
Timer intervals configured, Hello 10, Dead 40, Wait 40, Retransmit 5
Hello due in 00:00:01
Index 1/1, flood queue length 0
Next 0x0(0)/0x0(0)
Last flood scan length is 1, maximum is 1
Last flood scan time is 0 msec, maximum is 0 msec
Neighbor Count is 1 , Adjacent neighbor count is 1
Adjacent with neighbor 172.16.20.1
Suppress hello for 0 neighbor(s)
FastEthernet0/0 is up, line protocol is up
Internet address is 172.16.30.1/24, Area 0
Process ID 102, Router ID 172.16.40.1, Network Type BROADCAST, Cost: 1
Transmit Delay is 1 sec, State DR, Priority 1
Designated Router (ID) 172.16.40.1, Interface address 172.16.30.1
No backup designated router on this network
Timer intervals configured, Hello 10, Dead 40, Wait 40, Retransmit 5
Hello due in 00:00:02
Index 2/2, flood queue length 0
Next 0x0(0)/0x0(0)
Last flood scan length is 1, maximum is 1
Last flood scan time is 0 msec, maximum is 0 msec
Neighbor Count is 0, Adjacent neighbor count is 0
Suppress hello for 0 neighbor(s)
Serial0/0/1 is up, line protocol is up
Internet address is 172.16.40.1/24, Area 0
Process ID 102, Router ID 172.16.40.1, Network Type POINT-TO-POINT, Cost: 64
Transmit Delay is 1 sec, State POINT-TO-POINT,
Timer intervals configured, Hello 10, Dead 40, Wait 40, Retransmit 5
Hello due in 00:00:08
Index 3/3, flood queue length 0
Next 0x0(0)/0x0(0)
Last flood scan length is 1, maximum is 1
Last flood scan time is 0 msec, maximum is 0 msec
Suppress hello for 0 neighbor(s)
Which brings me to the original reason I re-created this topology... I was confused about the LINK COUNTS
here:
OSPF Router with ID (172.16.40.1) (Process ID 102)
Router Link States (Area 0)
Link ID ADV Router Age Seq# Checksum Link count
172.16.10.1 172.16.10.1 542 0x80000002 0x0067cd 1
172.16.20.1 172.16.20.1 90 0x80000004 0x00a551 3
172.16.40.1 172.16.40.1 37 0x80000004 0x00e47c 4
Net Link States (Area 0)
Link ID ADV Router Age Seq# Checksum
172.16.10.1 172.16.10.1 542 0x80000001 0x00953d
The steps of recreating the lab were helpful, but this link answered the question:
Here is the output of each router's command show ip ospf interface as they are
set up one at a time.
LabA - No OSPF at B, C, or D yet
show ip ospf database
OSPF Router with ID (172.16.10.1) (Process ID 100)
Router Link States (Area 0)
Link ID ADV Router Age Seq# Checksum Link count
172.16.10.1 172.16.10.1 44 0x80000001 0x00b24b 1
LabB - No OSPF at C or D yet
show ip ospf database
OSPF Router with ID (172.16.20.1) (Process ID 101)
Router Link States (Area 0)
Link ID ADV Router Age Seq# Checksum Link count
172.16.10.1 172.16.10.1 145 0x80000002 0x0067cd 1
172.16.20.1 172.16.20.1 32 0x80000003 0x006e8f 2
Net Link States (Area 0)
Link ID ADV Router Age Seq# Checksum
172.16.10.1 172.16.10.1 145 0x80000001 0x00953d
the 20.2 interface on this router has 2 ospf links.
The left-facing out to RA, a crossover cable
The right-facing out to RC, a serial cable.
If the solution I found is correct, why is this serial link not being counted twice? The solution (I think)
is revealed after the configuration of the next router...
LabC - No OSPF at D yet
show ip ospf database
OSPF Router with ID (172.16.40.1) (Process ID 102)
Router Link States (Area 0)
Link ID ADV Router Age Seq# Checksum Link count
172.16.10.1 172.16.10.1 542 0x80000002 0x0067cd 1
172.16.20.1 172.16.20.1 90 0x80000004 0x00a551 3
172.16.40.1 172.16.40.1 37 0x80000004 0x00e47c 4
Net Link States (Area 0)
Link ID ADV Router Age Seq# Checksum
172.16.10.1 172.16.10.1 542 0x80000001 0x00953d
NOW we can see that the 20.1 link, which is the right-facing interface on LabB.. aka the router ID..
has THREE OSPF links.
Nothing changed on the left side of B. But on the right side, we now have an active OSPF router at the
other end of the link. This leads me to believe that the forum post was correct that 'serial links are counted twice',
but, more specifically, BOTH ENDS of the serial(PPP) link are counted... IF there is an OSPF router on each end.
This is backed up by the fact that LabC, OSPF id 40.1, has four OSPF links. The top-facing link to the 30
network DOES count.. even though it has no OSPF router on the other end. It counts because it's not a serial link.
The requirement of having an OSPF router on the other end for an interface to count here, only applies
to serial links. And pertains to BOTH ends of the link being counted.
In LabC's case, we have one serial at left, being counted twice. One ethernet at top, being counted once. And
one serial at right only being counted once because LabD is not active with OSPF yet.
If this is correct, then we should see Lab C's 40.1 count go to 5 after LabD is set for OSPF....
LabD - all 4 routers have OSPF
show ip ospf database
OSPF Router with ID (172.16.50.1) (Process ID 103)
Router Link States (Area 0)
Link ID ADV Router Age Seq# Checksum Link count
172.16.10.1 172.16.10.1 785 0x80000002 0x0067cd 1
172.16.20.1 172.16.20.1 333 0x80000004 0x00a551 3
172.16.40.1 172.16.40.1 111 0x80000005 0x00013b 5
172.16.50.1 172.16.50.1 53 0x80000003 0x001023 3
Net Link States (Area 0)
Link ID ADV Router Age Seq# Checksum
172.16.10.1 172.16.10.1 785 0x80000001 0x00953d
and back to LabC.....
show ip ospf database
OSPF Router with ID (172.16.40.1) (Process ID 102)
Router Link States (Area 0)
Link ID ADV Router Age Seq# Checksum Link count
172.16.10.1 172.16.10.1 1174 0x80000002 0x0067cd 1
172.16.20.1 172.16.20.1 722 0x80000004 0x00a551 3
172.16.40.1 172.16.40.1 500 0x80000005 0x00013b 5
172.16.50.1 172.16.50.1 441 0x80000003 0x001023 3
Net Link States (Area 0)
Link ID ADV Router Age Seq# Checksum
172.16.10.1 172.16.10.1 1174 0x80000001 0x00953d
Looks good! The link count for each router makes sense if you count the serial interfaces twice (one for each end).
the OSPF databases now match across all 4 routers.
NOTE that this is a database of routers, identified by
router ID. It is not a topology that lists routers AND routes, like in
the "equivalent" eigrp command show eigrp topology
Note that the .30 network is NOT represented here.
LabA#
show ip ospf database
OSPF Router with ID (172.16.10.1) (Process ID 100)
Router Link States (Area 0)
Link ID ADV Router Age Seq# Checksum Link count
172.16.10.1 172.16.10.1 1138 0x80000002 0x0067cd 1
172.16.20.1 172.16.20.1 686 0x80000004 0x00a551 3
172.16.40.1 172.16.40.1 463 0x80000005 0x00013b 5
172.16.50.1 172.16.50.1 404 0x80000003 0x001023 3
Net Link States (Area 0)
Link ID ADV Router Age Seq# Checksum
172.16.10.1 172.16.10.1 1138 0x80000001 0x00953d
LabB#
show ip ospf database
OSPF Router with ID (172.16.20.1) (Process ID 101)
Router Link States (Area 0)
Link ID ADV Router Age Seq# Checksum Link count
172.16.10.1 172.16.10.1 1151 0x80000002 0x0067cd 1
172.16.20.1 172.16.20.1 699 0x80000004 0x00a551 3
172.16.40.1 172.16.40.1 476 0x80000005 0x00013b 5
172.16.50.1 172.16.50.1 417 0x80000003 0x001023 3
Net Link States (Area 0)
Link ID ADV Router Age Seq# Checksum
172.16.10.1 172.16.10.1 1151 0x80000001 0x00953d
LabC#
show ip ospf database
OSPF Router with ID (172.16.40.1) (Process ID 102)
Router Link States (Area 0)
Link ID ADV Router Age Seq# Checksum Link count
172.16.10.1 172.16.10.1 1174 0x80000002 0x0067cd 1
172.16.20.1 172.16.20.1 722 0x80000004 0x00a551 3
172.16.40.1 172.16.40.1 500 0x80000005 0x00013b 5
172.16.50.1 172.16.50.1 441 0x80000003 0x001023 3
Net Link States (Area 0)
Link ID ADV Router Age Seq# Checksum
172.16.10.1 172.16.10.1 1174 0x80000001 0x00953d
LabD#
show ip ospf database
OSPF Router with ID (172.16.50.1) (Process ID 103)
Router Link States (Area 0)
Link ID ADV Router Age Seq# Checksum Link count
172.16.10.1 172.16.10.1 785 0x80000002 0x0067cd 1
172.16.20.1 172.16.20.1 333 0x80000004 0x00a551 3
172.16.40.1 172.16.40.1 111 0x80000005 0x00013b 5
172.16.50.1 172.16.50.1 53 0x80000003 0x001023 3
Net Link States (Area 0)
Link ID ADV Router Age Seq# Checksum
172.16.10.1 172.16.10.1 785 0x80000001 0x00953d
Below is our routing tables with OSPF data. We do see the .30 network here.
Everyone can reach it:
LabA via LabB's 10.2
LabB via LabC's 20.2
LabC via direct connection
LabD via LabC's 40.1
LabA#
show ip route
172.16.0.0/16 is variably subnetted, 6 subnets, 2 masks
C 172.16.10.0/24 is directly connected, FastEthernet0/0
L 172.16.10.1/32 is directly connected, FastEthernet0/0
O 172.16.20.0/24 [110/65] via 172.16.10.2, 00:28:03, FastEthernet0/0
O 172.16.30.0/24 [110/66] via 172.16.10.2, 00:21:35, FastEthernet0/0
O 172.16.40.0/24 [110/129] via 172.16.10.2, 00:21:25, FastEthernet0/0
O 172.16.50.0/24 [110/130] via 172.16.10.2, 00:17:40, FastEthernet0/0
LabB#
show ip route
172.16.0.0/16 is variably subnetted, 7 subnets, 2 masks
C 172.16.10.0/24 is directly connected, FastEthernet0/0
L 172.16.10.2/32 is directly connected, FastEthernet0/0
C 172.16.20.0/24 is directly connected, Serial0/0/0
L 172.16.20.1/32 is directly connected, Serial0/0/0
O 172.16.30.0/24 [110/65] via 172.16.20.2, 00:27:04, Serial0/0/0
O 172.16.40.0/24 [110/128] via 172.16.20.2, 00:26:54, Serial0/0/0
O 172.16.50.0/24 [110/129] via 172.16.20.2, 00:23:09, Serial0/0/0
LabC#
show ip route
172.16.0.0/16 is variably subnetted, 8 subnets, 2 masks
O 172.16.10.0/24 [110/65] via 172.16.20.1, 00:27:52, Serial0/0/0
C 172.16.20.0/24 is directly connected, Serial0/0/0
L 172.16.20.2/32 is directly connected, Serial0/0/0
C 172.16.30.0/24 is directly connected, FastEthernet0/0
L 172.16.30.1/32 is directly connected, FastEthernet0/0
C 172.16.40.0/24 is directly connected, Serial0/0/1
L 172.16.40.1/32 is directly connected, Serial0/0/1
O 172.16.50.0/24 [110/65] via 172.16.40.2, 00:23:36, Serial0/0/1
LabD#
show ip route
172.16.0.0/16 is variably subnetted, 7 subnets, 2 masks
O 172.16.10.0/24 [110/129] via 172.16.40.1, 00:25:20, Serial0/0/0
O 172.16.20.0/24 [110/128] via 172.16.40.1, 00:25:20, Serial0/0/0
O 172.16.30.0/24 [110/65] via 172.16.40.1, 00:25:20, Serial0/0/0
C 172.16.40.0/24 is directly connected, Serial0/0/0
L 172.16.40.2/32 is directly connected, Serial0/0/0
C 172.16.50.0/24 is directly connected, FastEthernet0/0
L 172.16.50.1/32 is directly connected, FastEthernet0/0
moving on.......
9.5 - OSPF DR and BDR Elections
EachRouter(config)#
hostname X (A, B, or C)
EachRouter(config)#
line con 0
EachRouter(config-line)#
exec-timeout 0 0
A(config)#
int f0/0
A(config-if)#
ip addr 10.1.1.1 255.255.255.0
A(config-if)#
no shut
A(config)#
router ospf 12345
A(config-router)#
net 10.1.1.0 0.0.0.255 area 0
00:23:30: %OSPF-5-ADJCHG: Process 12345, Nbr 10.1.1.3 on FastEthernet0/0 from LOADING to FULL, Loading Done
00:23:30: %OSPF-5-ADJCHG: Process 12345, Nbr 10.1.1.2 on FastEthernet0/0 from LOADING to FULL, Loading Done
A#
show ip ospf int
note this output was generated AFTER all 3 routers set for OSPF
FastEthernet0/0 is up, line protocol is up
Internet address is 10.1.1.1/24, Area 0
Process ID 12345, Router ID 10.1.1.1, Network Type BROADCAST, Cost: 1
Transmit Delay is 1 sec, State DROTHER, Priority 1
Designated Router (ID) 10.1.1.3, Interface address 10.1.1.3
Backup Designated Router (ID) 10.1.1.2, Interface address 10.1.1.2
Timer intervals configured, Hello 10, Dead 40, Wait 40, Retransmit 5
Hello due in 00:00:04
Index 1/1, flood queue length 0
Next 0x0(0)/0x0(0)
Last flood scan length is 1, maximum is 1
Last flood scan time is 0 msec, maximum is 0 msec
Neighbor Count is 2, Adjacent neighbor count is 2
Adjacent with neighbor 10.1.1.3 (Designated Router)
Adjacent with neighbor 10.1.1.2 (Backup Designated Router)
Suppress hello for 0 neighbor(s)
A(config-if)#shut
A(config-if)#
%LINK-5-CHANGED: Interface FastEthernet0/0, changed state to administratively down
%LINEPROTO-5-UPDOWN: Line protocol on Interface FastEthernet0/0, changed state to down
00:40:28: %OSPF-5-ADJCHG: Process 12345, Nbr 10.1.1.2 on FastEthernet0/0 from FULL to DOWN, Neighbor Down: Interface down or detached
00:40:28: OSPF: Build router LSA for area 0, router ID 10.1.1.1, seq 0xffffffff80000003
00:40:28: %OSPF-5-ADJCHG: Process 12345, Nbr 10.1.1.3 on FastEthernet0/0 from FULL to DOWN, Neighbor Down: Interface down or detached
00:40:28: OSPF: Build router LSA for area 0, router ID 10.1.1.1, seq 0xffffffff80000004
00:40:28: OSPF: Build router LSA for area 0, router ID 10.1.1.1, seq 0xffffffff80000004
A(config-if)#no shut
A(config-if)#
%LINK-5-CHANGED: Interface FastEthernet0/0, changed state to up
%LINEPROTO-5-UPDOWN: Line protocol on Interface FastEthernet0/0, changed state to up
00:40:48: OSPF: Build router LSA for area 0, router ID 10.1.1.1, seq 0xffffffff80000004
00:41:27: OSPF: Backup seen Event before WAIT timer on FastEthernet0/0
00:41:27: OSPF: DR/BDR election on FastEthernet0/0
00:41:27: OSPF: Elect BDR 10.1.1.2
00:41:27: OSPF: Elect DR 10.1.1.3
00:41:27: DR: 10.1.1.3 (Id) BDR: 10.1.1.2 (Id)
00:41:27: OSPF: Send DBD to 10.1.1.3 on FastEthernet0/0 seq 0x5accb8e2 opt 0x00 flag 0x7 len 32
B(config)#
int f0/0
B(config-if)#
ip addr 10.1.1.2 255.255.255.0
B(config-if)#
no shut
B(config)#
router ospf 12345
B(config-router)#
net 10.1.1.0 0.0.0.255 area 0
00:23:29: %OSPF-5-ADJCHG: Process 12345, Nbr 10.1.1.3 on FastEthernet0/0 from LOADING to FULL, Loading Done
00:23:29: %OSPF-5-ADJCHG: Process 12345, Nbr 10.1.1.1 on FastEthernet0/0 from LOADING to FULL, Loading Done
B#
show ip ospf int
note this output was generated AFTER all 3 routers set for OSPF
FastEthernet0/0 is up, line protocol is up
Internet address is 10.1.1.2/24, Area 0
Process ID 12345, Router ID 10.1.1.2, Network Type BROADCAST, Cost: 1
Transmit Delay is 1 sec, State BDR, Priority 1
Designated Router (ID) 10.1.1.3, Interface address 10.1.1.3
Backup Designated Router (ID) 10.1.1.2, Interface address 10.1.1.2
Timer intervals configured, Hello 10, Dead 40, Wait 40, Retransmit 5
Hello due in 00:00:05
Index 1/1, flood queue length 0
Next 0x0(0)/0x0(0)
Last flood scan length is 1, maximum is 1
Last flood scan time is 0 msec, maximum is 0 msec
Neighbor Count is 2, Adjacent neighbor count is 2
Adjacent with neighbor 10.1.1.1
Adjacent with neighbor 10.1.1.3 (Designated Router)
Suppress hello for 0 neighbor(s)
B#debug ip ospf adj
OSPF adjacency events debugging is on
B#
00:39:21: OSPF: DR/BDR election on FastEthernet0/0
00:39:21: OSPF: Elect BDR 10.1.1.2
00:39:21: OSPF: Elect DR 10.1.1.3
00:39:21: DR: 10.1.1.3 (Id) BDR: 10.1.1.2 (Id)
00:41:01: %OSPF-5-ADJCHG: Process 12345, Nbr 10.1.1.1 on FastEthernet0/0 from FULL to DOWN, Neighbor Down: Dead timer expired
00:41:01: %OSPF-5-ADJCHG: Process 12345, Nbr 10.1.1.1 on FastEthernet0/0 from FULL to DOWN, Neighbor Down: Interface down or detached
00:41:01: OSPF: Build router LSA for area 0, router ID 10.1.1.2, seq 0xffffffff80000003
00:41:01: OSPF: DR/BDR election on FastEthernet0/0
00:41:01: OSPF: Elect BDR 10.1.1.2
00:41:01: OSPF: Elect DR 10.1.1.3
C(config)#
int f0/0
C(config-if)#
ip addr 10.1.1.3 255.255.255.0
C(config-if)#
no shut
C(config)#
router ospf 12345
C(config-router)#
net 10.1.1.0 0.0.0.255 area 0
00:23:27: %OSPF-5-ADJCHG: Process 12345, Nbr 10.1.1.1 on FastEthernet0/0 from LOADING to FULL, Loading Done
00:23:27: %OSPF-5-ADJCHG: Process 12345, Nbr 10.1.1.2 on FastEthernet0/0 from LOADING to FULL, Loading Done
C#
show ip ospf int
note this output was generated AFTER all 3 routers set for OSPF
FastEthernet0/0 is up, line protocol is up
Internet address is 10.1.1.3/24, Area 0
Process ID 12345, Router ID 10.1.1.3, Network Type BROADCAST, Cost: 1
Transmit Delay is 1 sec, State DR, Priority 1
Designated Router (ID) 10.1.1.3, Interface address 10.1.1.3
Backup Designated Router (ID) 10.1.1.2, Interface address 10.1.1.2
Timer intervals configured, Hello 10, Dead 40, Wait 40, Retransmit 5
Hello due in 00:00:00
Index 1/1, flood queue length 0
Next 0x0(0)/0x0(0)
Last flood scan length is 1, maximum is 1
Last flood scan time is 0 msec, maximum is 0 msec
Neighbor Count is 2, Adjacent neighbor count is 2
Adjacent with neighbor 10.1.1.1
Adjacent with neighbor 10.1.1.2 (Backup Designated Router)
Suppress hello for 0 neighbor(s)
C#debug ip ospf adj
OSPF adjacency events debugging is on
C#
00:39:19: OSPF: DR/BDR election on FastEthernet0/0
00:39:19: OSPF: Elect BDR 10.1.1.2
00:39:19: OSPF: Elect DR 10.1.1.3
00:39:19: DR: 10.1.1.3 (Id) BDR: 10.1.1.2 (Id)
00:40:59: %OSPF-5-ADJCHG: Process 12345, Nbr 10.1.1.1 on FastEthernet0/0 from FULL to DOWN, Neighbor Down: Dead timer expired
00:40:59: %OSPF-5-ADJCHG: Process 12345, Nbr 10.1.1.1 on FastEthernet0/0 from FULL to DOWN, Neighbor Down: Interface down or detached
00:40:59: OSPF: Build router LSA for area 0, router ID 10.1.1.3, seq 0xffffffff80000003
00:40:59: OSPF: Build net LSA for area 0, router ID 10.1.1.3, seq 0xffffffff80000003
00:40:59: OSPF: DR/BDR election on FastEthernet0/0
00:40:59: OSPF: Elect BDR 10.1.1.2
00:40:59: OSPF: Elect DR 10.1.1.3
DR and BDR automtically set based on higest IP address
Note our network type is BROADCAST because we're using ethernet interfaces...
it would be point-to-point if using a serial connection
we want to manually overide the priority of the router. ZERO priority means it wont participate in the election process
MAX priority of 255 means no other router can beat it for DR
We'll set the priority for router A to 3.
It will beome the DR only after we shut/no shut the interface router
AND
manually power on/off the other two routers
A(config)#
int f0/0
A(config-int)#
ip ospf priority 3
A(config-int)#
shut
A(config-int)#
no shut
A#
debug ip ospf adj
B#
debug ip ospf adj
00:05:50: OSPF: DR/BDR election on FastEthernet0/0
00:05:50: OSPF: Elect BDR 10.1.1.2
00:05:50: OSPF: Elect DR 10.1.1.1
00:05:50: OSPF: Elect BDR 10.1.1.2
00:05:50: OSPF: Elect DR 10.1.1.1
00:05:50: DR: 10.1.1.1 (Id) BDR: 10.1.1.2 (Id)
00:05:50: OSPF: Send DBD to 10.1.1.1 on FastEthernet0/0 seq 0x10164ebb opt 0x00 flag 0x7 len 32
00:05:50: OSPF: Build router LSA for area 0, router ID 10.1.1.2, seq 0xffffffff80000002
00:05:52: OSPF: Rcv DBD from 10.1.1.1 on FastEthernet0/0 seq 0x20368093 opt 0x00 flag 0x7 len 32 mtu 1500 state EXSTART
00:05:52: OSPF: First DBD and we are not SLAVE
00:05:55: OSPF: Send DBD to 10.1.1.1 on FastEthernet0/0 seq 0x10164ebb opt 0x00 flag 0x7 len 32
00:05:55: OSPF: Rcv DBD from 10.1.1.1 on FastEthernet0/0 seq 0x10164ebb opt 0x00 flag 0x2 len 112 mtu 1500 state EXSTART
00:05:55: OSPF: NBR Negotiation Done. We are the MASTER
00:05:55: OSPF: Send DBD to 10.1.1.1 on FastEthernet0/0 seq 0x10164ebc opt 0x00 flag 0x3 len 52
00:05:55: OSPF: Rcv DBD from 10.1.1.1 on FastEthernet0/0 seq 0x10164ebc opt 0x00 flag 0x0 len 32 mtu 1500 state EXCHANGE
00:05:55: OSPF: Send DBD to 10.1.1.1 on FastEthernet0/0 seq 0x10164ebd opt 0x00 flag 0x1 len 32
00:05:55: OSPF: Rcv DBD from 10.1.1.1 on FastEthernet0/0 seq 0x10164ebd opt 0x00 flag 0x0 len 32 mtu 1500 state EXCHANGE
00:05:55: Exchange Done with 10.1.1.1 on FastEthernet0/0
00:05:55: OSPF: Database request to 10.1.1.1
00:05:55: OSPF: sent LS REQ packet to 10.1.1.1, length 36
00:05:55: OSPF: Rcv DBD from 10.1.1.1 on FastEthernet0/0 seq 0x10164ebd opt 0x00 flag 0x0 len 32 mtu 1500 state LOADING
00:05:55: Synchronized with with 10.1.1.1 on FastEthernet0/0, state FULL
00:05:55: %OSPF-5-ADJCHG: Process 12345, Nbr 10.1.1.1 on FastEthernet0/0 from LOADING to FULL, Loading Done
00:05:55: OSPF: Build router LSA for area 0, router ID 10.1.1.2, seq 0xffffffff80000002
C#
debug ip ospf adj
00:06:13: OSPF: DR/BDR election on FastEthernet0/0
00:06:13: OSPF: Elect BDR 10.1.1.2
00:06:13: OSPF: Elect DR 10.1.1.1
00:06:13: DR: 10.1.1.1 (Id) BDR: 10.1.1.2 (Id)
00:06:13: OSPF: Send DBD to 10.1.1.1 on FastEthernet0/0 seq 0x1cc5536d opt 0x00 flag 0x7 len 32
00:06:13: OSPF: Send DBD to 10.1.1.2 on FastEthernet0/0 seq 0x3d51ca66 opt 0x00 flag 0x7 len 32
00:06:13: OSPF: Build router LSA for area 0, router ID 10.1.1.3, seq 0xffffffff80000002
00:06:17: OSPF: Rcv DBD from 10.1.1.1 on FastEthernet0/0 seq 0x6b532eec opt 0x00 flag 0x7 len 32 mtu 1500 state EXSTART
00:06:17: OSPF: First DBD and we are not SLAVE
00:06:17: OSPF: Rcv DBD from 10.1.1.2 on FastEthernet0/0 seq 0x783110f4 opt 0x00 flag 0x7 len 32 mtu 1500 state EXSTART
00:06:17: OSPF: First DBD and we are not SLAVE
00:06:18: OSPF: Send DBD to 10.1.1.2 on FastEthernet0/0 seq 0x3d51ca66 opt 0x00 flag 0x7 len 32
00:06:18: OSPF: Send DBD to 10.1.1.1 on FastEthernet0/0 seq 0x1cc5536d opt 0x00 flag 0x7 len 32
00:06:18: OSPF: Rcv DBD from 10.1.1.2 on FastEthernet0/0 seq 0x3d51ca66 opt 0x00 flag 0x2 len 132 mtu 1500 state EXSTART
00:06:18: OSPF: NBR Negotiation Done. We are the MASTER
00:06:18: OSPF: Send DBD to 10.1.1.2 on FastEthernet0/0 seq 0x3d51ca67 opt 0x00 flag 0x3 len 52
00:06:18: OSPF: Rcv DBD from 10.1.1.1 on FastEthernet0/0 seq 0x1cc5536d opt 0x00 flag 0x2 len 132 mtu 1500 state EXSTART
00:06:18: OSPF: NBR Negotiation Done. We are the MASTER
00:06:18: OSPF: Send DBD to 10.1.1.1 on FastEthernet0/0 seq 0x1cc5536e opt 0x00 flag 0x3 len 52
00:06:18: OSPF: Rcv DBD from 10.1.1.2 on FastEthernet0/0 seq 0x3d51ca67 opt 0x00 flag 0x0 len 32 mtu 1500 state EXCHANGE
00:06:18: OSPF: Send DBD to 10.1.1.2 on FastEthernet0/0 seq 0x3d51ca68 opt 0x00 flag 0x1 len 32
00:06:18: OSPF: Rcv DBD from 10.1.1.1 on FastEthernet0/0 seq 0x1cc5536e opt 0x00 flag 0x0 len 32 mtu 1500 state EXCHANGE
00:06:18: OSPF: Send DBD to 10.1.1.1 on FastEthernet0/0 seq 0x1cc5536f opt 0x00 flag 0x1 len 32
00:06:18: OSPF: Rcv DBD from 10.1.1.2 on FastEthernet0/0 seq 0x3d51ca68 opt 0x00 flag 0x0 len 32 mtu 1500 state EXCHANGE
00:06:18: Exchange Done with 10.1.1.2 on FastEthernet0/0
00:06:18: OSPF: Database request to 10.1.1.2
00:06:18: OSPF: sent LS REQ packet to 10.1.1.2, length 48
00:06:18: OSPF: Rcv DBD from 10.1.1.1 on FastEthernet0/0 seq 0x1cc5536f opt 0x00 flag 0x0 len 32 mtu 1500 state EXCHANGE
verify on all three routers
A#
show ip ospf interface f0/0
FastEthernet0/0 is up, line protocol is up
Internet address is 10.1.1.1/24, Area 0
Process ID 12345, Router ID 10.1.1.1, Network Type BROADCAST, Cost: 1
Transmit Delay is 1 sec, State DR, Priority 3
Designated Router (ID) 10.1.1.1, Interface address 10.1.1.1
Backup Designated Router (ID) 10.1.1.2, Interface address 10.1.1.2
Timer intervals configured, Hello 10, Dead 40, Wait 40, Retransmit 5
Hello due in 00:00:09
Index 1/1, flood queue length 0
Next 0x0(0)/0x0(0)
Last flood scan length is 1, maximum is 1
Last flood scan time is 0 msec, maximum is 0 msec
Neighbor Count is 2, Adjacent neighbor count is 2
Adjacent with neighbor 10.1.1.2 (Backup Designated Router)
Adjacent with neighbor 10.1.1.3
Suppress hello for 0 neighbor(s)
A#
show ip ospf neighbor
Neighbor ID Pri State Dead Time Address Interface
10.1.1.2 1 FULL/BDR 00:00:37 10.1.1.2 FastEthernet0/0
10.1.1.3 1 FULL/DROTHER 00:00:30 10.1.1.3 FastEthernet0/0
B#
show ip ospf interface f0/0
FastEthernet0/0 is up, line protocol is up
Internet address is 10.1.1.2/24, Area 0
Process ID 12345, Router ID 10.1.1.2, Network Type BROADCAST, Cost: 1
Transmit Delay is 1 sec, State BDR, Priority 1
Designated Router (ID) 10.1.1.1, Interface address 10.1.1.1
Backup Designated Router (ID) 10.1.1.2, Interface address 10.1.1.2
Timer intervals configured, Hello 10, Dead 40, Wait 40, Retransmit 5
Hello due in 00:00:08
Index 1/1, flood queue length 0
Next 0x0(0)/0x0(0)
Last flood scan length is 1, maximum is 1
Last flood scan time is 0 msec, maximum is 0 msec
Neighbor Count is 2, Adjacent neighbor count is 2
Adjacent with neighbor 10.1.1.1 (Designated Router)
Adjacent with neighbor 10.1.1.3
Suppress hello for 0 neighbor(s)
B#
show ip ospf neighbor
Neighbor ID Pri State Dead Time Address Interface
10.1.1.1 3 FULL/DR 00:00:35 10.1.1.1 FastEthernet0/0
10.1.1.3 1 FULL/DROTHER 00:00:31 10.1.1.3 FastEthernet0/0
C#
show ip ospf interface f0/0
FastEthernet0/0 is up, line protocol is up
Internet address is 10.1.1.3/24, Area 0
Process ID 12345, Router ID 10.1.1.3, Network Type BROADCAST, Cost: 1
Transmit Delay is 1 sec, State DROTHER, Priority 1
Designated Router (ID) 10.1.1.1, Interface address 10.1.1.1
Backup Designated Router (ID) 10.1.1.2, Interface address 10.1.1.2
Timer intervals configured, Hello 10, Dead 40, Wait 40, Retransmit 5
Hello due in 00:00:06
Index 1/1, flood queue length 0
Next 0x0(0)/0x0(0)
Last flood scan length is 1, maximum is 1
Last flood scan time is 0 msec, maximum is 0 msec
Neighbor Count is 2, Adjacent neighbor count is 2
Adjacent with neighbor 10.1.1.1 (Designated Router)
Adjacent with neighbor 10.1.1.2 (Backup Designated Router)
Suppress hello for 0 neighbor(s)
C#
show ip ospf neighbor/span>
Neighbor ID Pri State Dead Time Address Interface
10.1.1.1 3 FULL/DR 00:00:35 10.1.1.1 FastEthernet0/0
10.1.1.2 1 FULL/BDR 00:00:37 10.1.1.2 FastEthernet0/0
Router1 is the DR with priority 3
still need more work to understand the output of the defbu ospf adj
Chapter 9 Review Questions
1. There are three possible routes for a router to reach a destination network:
OSPF with a metric of 782
RIPv2 with a metric of 4
EIGRP with a composite metric of 20514560
Which route will be installed in the routing table?
EIGRP because it has the lowest Administrative Distance, and AD is always used before metric
ADs are:
ExternalEIGRP 170
RIP 120
OSPF 110
IGRP 100
EIGRP 90
Static 1
Connected 0
2. Which EIGRP information is held in RAM and maintained through the use of Hello and update packets?
Neighbor table
and
toplogy table
3. Describe the process identifier that is used to run OSPF on a router
The OSPF process id is only locally significant. A random number can be selected. But it's required in order to identify
a unique OSPF database instance. You can use the same, or a different number on each router, doesnt matter.
Any number can be used from 1 to 65,535. Process ID is supplied as an argument to the command router ospf
NOT to be confused with the area number which can be any number up to 4 billion. The area id identifies a logical grouping of routers.
area id is supplied as argument to the OSPF network id and mask command
Ex:
R1(config)#
router ospf 12345
R1(config-router)#
net 10.1.1.0 0.0.0.255 area 0
4. Where are EIGRP successor routes stored?
EIGRP succesor routers are stored in the routing table. The "succesor" is the successful or primary route.
The successor route is ALSO listed in the topology table,
The feasible successor is a BACKUP route and will ONLY be listed in the topology table, unless the successor route fails,
in which case the feasible successor would become the successor
Note that my EIGRP setup doesnt seem to folow this.
CTRL-F jump to "remotely connected via remote ingress ip address"
the book states that EIGRP is automatically load-balancing our two links from R1 to corp.. is this why there is no feasible successor here?
I did some research and found that in our case, we are not using a Feasible Successor. You CAN have two Successors with equal metric, in which case EIGRP will
automatically load-balance.
But I wanted to find out what a Feasible Successor actually looks like in the EIGRP topology table..
Kevin Wallace EIGRP article
Conclusion:
EIGRP topology table wouldnt specifically say "Feasible Successor", but you would know by two routes appearing, one with a lower metric.
In my topology we have two equal-metric links and they are both considered "Successors". EIGRP uses them equally (load-balanced)
Corp#
show ip eigrp toplogy
[cut]
P 172.16.10.0/24, 1 successors, FD is 28160
via 10.1.5.2 (28160/25600), FastEthernet0/0
P 192.168.10.0/24, 2 successors, FD is 2172416
via 10.1.3.2 (2172416/28160), Serial0/0/1
via 10.1.2.2 (2172416/28160), Serial0/0/0
P 192.168.20.0/24, 2 successors, FD is 2172416
via 10.1.3.2 (2172416/28160), Serial0/0/1
via 10.1.2.2 (2172416/28160), Serial0/0/0
P 192.168.30.0/24, 1 successors, FD is 2172416
via 10.1.4.2 (2172416/28160), Serial0/1/0
P 192.168.40.0/24, 1 successors, FD is 2172416
via 10.1.4.2 (2172416/28160), Serial0/1/0
5. Which command will display all the EIGRP feasible successor routes to a known router.
show ip eigrp topology
6. Find the configuration error. You type the following into your router, but dont see any routes in the routing table?
Router(config)#
router ospf 1
Router(config-router)#
network 10.0.0.0 255.0.0.0
wrong wildcard mask
instead, could have used
0.255.255.255
or
0.0.0.255
the point is we need to specify the first octet as "allowed" into our OSPF config with a 0 mask.
The remaining bits are 'dont care' bits aka 'wildcard' aka 255
7. Which three protocols support VLSM, summarization, and discontigous networking?
RIPv2
EIGRP
OSPF
all 3 build and mainting routing tables, provide classless routing which allows VLSM, summarization, and discontigous networks
RIPv1 and IGRP build/maintain routing tables, but dont offer classless routing
8. Which are true regarding OSPF areas?
the 'backbone' is area 0
if using other areas, they all must directly connect to area 0
9. Which two network types have a designated router and a backup designated router?
Broadcast
NBMA- Non broadcast multi access. Ex: Frame Relay
network types that DO NOT use DR/BDR:
point to point
broadcast multipoint
10. You need to configure a router with a distance-vector protocol that allows classless routing. Which to use?
EIGRP is considered 'advanced distance vector' (ripv2 wasnt an option)
11. You need the IP address of the devices with which the router has established an adjacency.
Also, the retransmit interval and the queue counts for the adjacent routers need to be checked. What command will display the required information?
show ip eigrp neighbors
WRONG: show ip eigrp adjacency - there is no such command.. the word 'adjacency' is only used with debug ip OSPF adjacency
here are the possible commands for show ip eigrp and debug ip eigrp
show ip eigrp ?
interfaces IP-EIGRP interfaces
neighbors IP-EIGRP neighbors
topology IP-EIGRP Topology Table
traffic IP-EIGRP Traffic Statistics
debug ip eigrp ?
summary IP-EIGRP summary route processing
12. You cant establish an adjacency relationship on a common ethernet link between two routers. Based on the output below, what is the cause of the problem?
RouterA#
Ethernet0/0 is up, line protocol is up
Internet Address 172.16.1.2/16, Area 0
Process ID 2, Router ID 172.126.1.2, Network Type BROADCAST, Cost: 10
Transmit Delay is 1 sec, State DR, Priority 1
Designated Router (ID) 172.16.1.2, interface address 172.16.1.1.
No backup designated router on this network
Timer intervals configured, Hello 5, Dead 20, Wait 20, Retransmit 5
Router B#
Internet Address 172.16.1.1/16, Area 0
Process ID 2, Router ID 172.126.1.1, Network Type BROADCAST, Cost: 10
Transmit Delay is 1 sec, State DR, Priority 1
Designated Router (ID) 172.16.1.1, interface address 172.16.1.2.
No backup designated router on this network
Timer intervals configured, Hello 10, Dead 40, Wait 40, Retransmit 5
mismatched timer intervals
OSPF default Hello is 10 and Dead is 40... RouterA was modified
13. Which is true regarding EIGRP successor routes?
Used in the routing table
also appears in the topolgy table
may (or may not) have a backup feasabile successor
14. Which type of OSPF network will elect a backup designated router?
broadcast multi-access
non-broadcast multiaccess
types of network that will NOT elect a BDR:
point to point and brodacast multipoint (hub/spoke topology)
15. Which two commands will place network 10.2.3.0/24 into area 0?
Router(config)#
router ospf 10
Router(config-router)#
network 10.2.3.0 0.0.0.255 area 0
16. With which network type will OSPF establish router adjacencies but not perform the DR/BDR election process?
Point to point
no election process occurs, there is never a DR on point to point
17. What are three reasons for creating OSPF in a heirarchical design?
decrease routing overhead
speed up convergence
confine stability to single areas of the network
18. What is the administrative distance of OSPF?
110
19.
no auto summary
the network is considered discontigous because we have two classful network subnetted (on the left and right),
seperated by a different classful address.
if auto summarization is taking place, the routers cant determine which side is which because both sides would be summarized as
Class B, 172.16.0.0, which isnt specific enough to distinguish between the sides.
20. IF routers in a single area are configured with the same priority value, what value does a router use for the OSPF router ID in the absence of a loopback interface?
The highest IP of any PHSYICAL interface.
Trick question. Highest IP of any LOGICAL interface is an option. And is correct IF you had logical interfaces, but the question
states that any "logical interfaces are absent".
At OSPF startup, the highest IP of *any* active interface on the router becomes the OSPF router ID. If you have loopback (logical) interfaces configured,
one of them (the largest IP) will *override* the phsyical interfaces and the loopback IP becomes the RID.
Reference for which loopback (if multiple) wins:
packetpushers.net
------------------------------------------------------------------------------
END CHAPTER 9
41 hours 2-14 thru 2-28-22
original total 184 hours
14 hours review 12-26 thru 12-28-22
review total hours 46
book page 502/822
184 + 46 = 230 hours * 60 = (13,800 min) / 500 pages =
avg 28 min/page (includes reading and exercises/labs + online research)
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router>
enable
router# erase startup-config
router# erase startup-config
Erasing the nvram filesystem will remove all configuration files! Continue? [confirm]
[OK]
Erase of nvram: complete
%SYS-7-NV_BLOCK_INIT: Initialized the geometry of nvram
router#
user mode
router> ?
router> enable
privileged exec mode
router# ?
router# config
Configuring from terminal, memory, or network [terminal]?
terminal is the default, enter to select
router(config)# ?
router(conf)# interface g0/0/0
router(conf-if)# ?
router(conf-if)# exit
back one level
router(conf)# exit
back one level
router# disable
back to user mode
router>
router> ?
<1-99> Session number to resume
connect Open a terminal connection
disable Turn off privileged commands
disconnect Disconnect an existing network connection
enable Turn on privileged commands
exit Exit from the EXEC
logout Exit from the EXEC
ping Send echo messages
resume Resume an active network connection
show Show running system information
ssh Open a secure shell client connection
telnet Open a telnet connection
terminal Set terminal line parameters
traceroute Trace route to destination
user mode
router> enable
privileged exec mode
router# ?
<1-99> Session number to resume
auto Exec level Automation
clear Reset functions
clock Manage the system clock
configure Enter configuration mode
connect Open a terminal connection
copy Copy from one file to another
debug Debugging functions (see also 'undebug')
delete Delete a file
dir List files on a filesystem
disable Turn off privileged commands
disconnect Disconnect an existing network connection
enable Turn on privileged commands
erase Erase a filesystem
exit Exit from the EXEC
logout Exit from the EXEC
mkdir Create new directory
more Display the contents of a file
no Disable debugging informations
ping Send echo messages
reload Halt and perform a cold restart
resume Resume an active network connection
rmdir Remove existing directory
send Send a message to other tty lines
setup Run the SETUP command facility
show Show running system information
ssh Open a secure shell client connection
telnet Open a telnet connection
terminal Set terminal line parameters
traceroute Trace route to destination
undebug Disable debugging functions (see also 'debug')
vlan Configure VLAN parameters
write Write running configuration to memory, network, or terminal
router# config
Configuring from terminal, memory, or network [terminal]?
terminal is the default, enter to select
router(config)# ?
aaa Authentication, Authorization and Accounting.
access-list Add an access list entry
banner Define a login banner
bba-group Configure BBA Group
boot Modify system boot parameters
cdp Global CDP configuration subcommands
class-map Configure Class Map
clock Configure time-of-day clock
config-register Define the configuration register
crypto Encryption module
default Set a command to its defaults
do To run exec commands in config mode
dot11 IEEE 802.11 config commands
enable Modify enable password parameters
end Exit from configure mode
exit Exit from configure mode
flow Global Flow configuration subcommands
hostname Set system's network name
interface Select an interface to configure
ip Global IP configuration subcommands
ipv6 Global IPv6 configuration commands
key Key management
license Configure license features
line Configure a terminal line
lldp Global LLDP configuration subcommands
logging Modify message logging facilities
login Enable secure login checking
mac-address-table Configure the MAC address table
no Negate a command or set its defaults
ntp Configure NTP
parser Configure parser
policy-map Configure QoS Policy Map
port-channel EtherChannel configuration
priority-list Build a priority list
privilege Command privilege parameters
queue-list Build a custom queue list
radius RADIUS server configuration command
radius-server Modify Radius query parameters
router Enable a routing process
secure Secure image and configuration archival commands
security Infra Security CLIs
service Modify use of network based services
snmp-server Modify SNMP engine parameters
spanning-tree Spanning Tree Subsystem
tacacs-server Modify TACACS query parameters
username Establish User Name Authentication
vpdn Virtual Private Dialup Network
vpdn-group VPDN group configuration
router(conf)# interface g0/0/0
router(conf-if)# ?
arp Set arp type (arpa, probe, snap) or timeout
bandwidth Set bandwidth informational parameter
cdp CDP interface subcommands
channel-group Add this interface to an Etherchannel group
crypto Encryption/Decryption commands
custom-queue-list Assign a custom queue list to an interface
delay Specify interface throughput delay
description Interface specific description
duplex Configure duplex operation.
exit Exit from interface configuration mode
fair-queue Enable Fair Queuing on an Interface
hold-queue Set hold queue depth
ip Interface Internet Protocol config commands
ipv6 IPv6 interface subcommands
lldp LLDP interface subcommands
mac-address Manually set interface MAC address
media-type Configure media type
mtu Set the interface Maximum Transmission Unit (MTU)
no Negate a command or set its defaults
pppoe pppoe interface subcommands
pppoe-client pppoe client
priority-group Assign a priority group to an interface
service-policy Configure QoS Service Policy
shutdown Shutdown the selected interface
speed Configure speed operation.
standby HSRP interface configuration commands
tx-ring-limit Configure PA level transmit ring limit
router(conf-if)# exit
back one level
router(conf)# exit
back one level
router# disable
back to user mode
router>
Hands-on Lab 6.3 Using the Help and Editing Features
router#
?
router#
cl?
clear clock
router#
clock ?
set Set the date and time
router#
clock set 10:30:30 ?
<1-31> Day of the month
MONTH Month of the year
router#
clock set 10:30:30 17 January 2022
router#
router#
show clock
10:31:33.95 UTC Mon Jan 17 2022
keyboard commands
ctrl + A
beginning of line
ctrl + E
end of line
ctrl + B
back one character
ctrl + F
forward one character
ctrl + P
paste previous command
TAB
complete a partially typed command
router#
terminal no editing
turns off the keyboard shortcuts
router#
terminal editing
turns on the keyboard shortcuts
router#
show history
shows last 10 commands by default
router#
terminal history size 20
sets the history size to 20
Hands-on Lab 6.4 Saving a Router Configuration
router#
show startup-config
"startup config" AKA NVRAM
Using 672 bytes
!
version 16.6.4
no service timestamps log datetime msec
no service timestamps debug datetime msec
no service password-encryption
!
hostname Router
!
!
!
!
!
!
!
!
no ip cef
no ipv6 cef
!
!
!
!
!
!
!
!
!
!
!
!
spanning-tree mode pvst
!
!
!
!
!
!
interface GigabitEthernet0/0/0
no ip address
duplex auto
speed auto
shutdown
!
interface GigabitEthernet0/0/1
no ip address
duplex auto
speed auto
shutdown
!
interface GigabitEthernet0/0/2
no ip address
duplex auto
speed auto
shutdown
!
interface Vlan1
no ip address
shutdown
!
ip classless
!
ip flow-export version 9
!
!
!
!
!
!
!
!
line con 0
!
line aux 0
!
line vty 0 4
login
line vty 5 15
login
!
!
!
end
to copy a running config to NVRAM:
router#
copy running-config startup-config
to erase NVRAM:
router#
erase startup-config
router#
erase startup-config
Erasing the nvram filesystem will remove all configuration files! Continue? [confirm]
[OK]
Erase of nvram: complete
%SYS-7-NV_BLOCK_INIT: Initialized the geometry of nvram
router#
show startup-config
startup-config is not present
router#
reload
Proceed with reload? [confirm]
[output cut]
Would you like to enter the initial configuration dialog? [yes/no]:
Hands-on Lab 6.5 Setting Passwords
add a secret password
router(config)#
enable secret 1234
remove the secret password
router(config)#
no enable secret
Note youre not prompted for the secret, since you already had to provide
it in order to enter conf mode
add a regular password
router(config)#
enable password 4321
Can coexist with the secret password, but the two passwords must be different
----------------------------------------------------------------------
add password for Telnet aka VTY
router(config)#
line vty 0 15
16 virtual telnet lines on this router
We can set the whole range, a portion of the range, or a single line
router(config)#
login activate authentication
router(config)#
password telnet123
----------------------------------------------------------------------
add password for Auxiliary
router(config)#
line aux 0 there's only sone aux line
router(config)#
login activate authentication
router(config)#
password aux123
----------------------------------------------------------------------
add password for Console
router(config)#
line console 0 there's only one console line
router(config)#
login activate authentication
router(config)#
password console123
router(config)#
exec-timeout 0 0 min/sec
stop the console from timing out and logging you out
router(config)#
logging synchronous
dont overwrite input commands with console messages
Hands-on Lab 6.6 Setting the Hostname, Descriptions, IP Address, and Clock Rate
set router name
router(config)#
hostname routerA
------------------------------------------
set motd banner
routerA(config)#
banner ?
login Set login banner
motd Set Message of the Day banner
router(config)#
banner motd #
Enter TEXT message. End with the character '#'.
welcome to the router #
router(config)#
------------------------------------------
remove the banner
router(config)#
no banner motd
------------------------------------------
set login banner
router(config)#
banner login #
Enter TEXT message. End with the character '#'.
please login now #
router(config)#
------------------------------------------
add an IP address to an interface
router(config)#
do show interfaces use "do" to enable this command within config mode
GigabitEthernet0/0/0 is administratively down, line protocol is down (disabled)
---cut---
GigabitEthernet0/0/1 is administratively down, line protocol is down (disabled)
---cut---
GigabitEthernet0/0/2 is administratively down, line protocol is down (disabled)
---cut---
Vlan1 is administratively down, line protocol is down
router(config)#
interface g0/0/0
router(config-if)#
ip address 1.1.1.1 255.255.0.0
router(config-if)#
no shutdown
%LINK-5-CHANGED: Interface GigabitEthernet0/0/0, changed state to up
router(config-if)#
do show interfaces
GigabitEthernet0/0/0 is up, line protocol is down (disabled)
Internet address is 1.1.1.1/16
router(config-if)#
description WAN link to Miami
Chapter 6 Review Questions
1. You type show running-config and get this output:
---cut---
line console 0
Exec-timeout 1 44
Password 7 098C0BQR
Login
---cut---
What do the two numbers following the exec-timeout command mean?
minutes and seconds
2. Which connection method for connecting to a router is considered "out-of-band"?
auxiliary
The aux port can be configured to allow a modem to connect to the router.
It lets you dial up to a remote router in order to connect to the aux port if the router is down.
This method is considered "out of band" since its not connecting via "the network"
3. Which two commands are required when configuring SSH on your router?
ip domain-name name
username name password password
Example: Using SSH instead of Telnet
set your hostname, domain, and username
router(config)#
hostname Dallas
Dallas(config)#
ip domain-name Lammle.com
Dallas(config)#
username Michael password 1234
generate encryption keys
Dallas(config)#
crypto key generate rsa genral-keys modulus 1024
The name for the keys will be Michael.Lammle.com
% The key modulus size is 1024 bits
% Generating 1024 bit RSA keys, keys will be non-exportable...[ok]
*June 24 19:25:30.035: %SSH-5-ENABLED: SSH 1.99 has been enabled
enable SSH version 2
router(config)#
ssh version 2
connect to the vty lines of the router
router(config)#
line vty 0 1180
configure SSH and then Telnet as access protocols
router(config-line)#
transport input ssh telnet
4. Which command will show you wheter a DTE or a DCE cable is plugged into serial 0?
show controllers serial 0
will show whether DTE or DCE cable is connected to the interface
NOTE if it is a DTE connection you must add clocking with the
clock rate command
5. Which is a correct combination of file type and default location on a Cisco router?
IOS- flash memory
startup config- NVRAM
running config- RAM
6. You set the console password, but when you display the configuration, the password doesn't show up;
it looks like this:
[output cut]
line console 0
Exec-timeout 1 44
Password 7 098C0BQR
Login
[output cut]
What command would configure the password to be stored this way?
service password-encryption
7. Which command will configure all the default VTY ports on a router?
from global config mode:
line vty 0 4
will set all 5 default lines
8. Which command set the secret password to Cisco?
enable secret Cisco
9. If you wanted to see a message when logging into the router, which command would you use?
MOTD
10. Which prompt indicate that the router is currently in priviliged mode?
router#
11. What command do you type to save the configuration stored in RAM to NVRAM?
copy running-config startup-config
12. You try to telnet into SSFRouter from router to Corp and receive this message:
Corp#telnet SFRouter
Trying SFRouter (10.0.0.1)...Open
Password required, but none set
[Connection to SFRouter closed by foreing host]
Corp#
Which command sequence will address the problem correctly?
SFRouter(config)#
line vty 0 4
SFRouter(config-line)#
password password1234
SFRouter(config-line)#
login
13. Which command will delete the contents of NVRAM on a router?
erase startup-config
14. What is the problem with an interface if you type
show interface serial 9
and receive the following message?
Serial0 is administratively down, line protocol is down
is set to 'shut' by default, fix with no shut
15. Which command displays the configurable parameters and statistics of all interfaces on a router?
show interfaces
16. If you delete the contents of NVRAM and reboot the router, what mode will you be in?
setup mode
--- System Configuration Dialog ---
Would you like to enter the initial configuration dialog? [yes/no]:
17. You type the following command into the router and receive the following output:
Router#show serial 0/0
^
% Invalid input detected at '^' marker.
show interface serial 0/0
18. You type Router#sh ru and receive a % ambiguous command error.
Why did you receive this error?
not specific enough- there is more than one possible
show
command that starts with
ru
19. Which of the following commands will display the current
IP addressing and the layer 1 and 2 status of an interface?
show interfaces
GigabitEthernet0/0/0 is up, line protocol is down (disabled)
Hardware is ISR4331-3x1GE, address is 000d.bd45.db01 (bia 000d.bd45.db01)
Internet address is 1.1.1.1/16
MTU 1500 bytes, BW 1000000 Kbit, DLY 10 usec,
reliability 255/255, txload 1/255, rxload 1/255
Encapsulation ARPA, loopback not set
Keepalive not supported
Half Duplex, 1000Mbps, link type is auto, media type is Auto Select
output flow-control is on, input flow-control is on
ARP type: ARPA, ARP Timeout 04:00:00,
Last input 00:00:08, output 00:00:05, output hang never
Last clearing of "show interface" counters never
Input queue: 0/375/0 (size/max/drops); Total output drops: 0
Queueing strategy: fifo
Output queue :0/40 (size/max)
5 minute input rate 0 bits/sec, 0 packets/sec
5 minute output rate 0 bits/sec, 0 packets/sec
0 packets input, 0 bytes, 0 no buffer
Received 0 broadcasts (0 IP multicasts)
0 runts, 0 giants, 0 throttles
0 input errors, 0 CRC, 0 frame, 0 overrun, 0 ignored
0 watchdog, 1017 multicast, 0 pause input
0 input packets with dribble condition detected
0 packets output, 0 bytes, 0 underruns
0 output errors, 0 collisions, 1 interface resets
0 unknown protocol drops
0 babbles, 0 late collision, 0 deferred
0 lost carrier, 0 no carrier
0 output buffer failures, 0 output buffers swapped out
GigabitEthernet0/0/1 is administratively down, line protocol is down (disabled)
Hardware is ISR4331-3x1GE, address is 000d.bd45.db02 (bia 000d.bd45.db02)
MTU 1500 bytes, BW 1000000 Kbit, DLY 10 usec,
reliability 255/255, txload 1/255, rxload 1/255
Encapsulation ARPA, loopback not set
Keepalive not supported
output flow-control is on, input flow-control is on
ARP type: ARPA, ARP Timeout 04:00:00,
Last input 00:00:08, output 00:00:05, output hang never
Last clearing of "show interface" counters never
Input queue: 0/375/0 (size/max/drops); Total output drops: 0
Queueing strategy: fifo
Output queue :0/40 (size/max)
5 minute input rate 0 bits/sec, 0 packets/sec
5 minute output rate 0 bits/sec, 0 packets/sec
0 packets input, 0 bytes, 0 no buffer
Received 0 broadcasts (0 IP multicasts)
0 runts, 0 giants, 0 throttles
0 input errors, 0 CRC, 0 frame, 0 overrun, 0 ignored
0 watchdog, 1017 multicast, 0 pause input
0 input packets with dribble condition detected
0 packets output, 0 bytes, 0 underruns
0 output errors, 0 collisions, 1 interface resets
0 unknown protocol drops
0 babbles, 0 late collision, 0 deferred
0 lost carrier, 0 no carrier
0 output buffer failures, 0 output buffers swapped out
GigabitEthernet0/0/2 is administratively down, line protocol is down (disabled)
Hardware is ISR4331-3x1GE, address is 000d.bd45.db03 (bia 000d.bd45.db03)
MTU 1500 bytes, BW 1000000 Kbit, DLY 10 usec,
reliability 255/255, txload 1/255, rxload 1/255
Encapsulation ARPA, loopback not set
Keepalive not supported
Half Duplex, 1000Mbps, link type is auto, media type is unknown media type
output flow-control is on, input flow-control is on
ARP type: ARPA, ARP Timeout 04:00:00,
Last input 00:00:08, output 00:00:05, output hang never
Last clearing of "show interface" counters never
Input queue: 0/375/0 (size/max/drops); Total output drops: 0
Queueing strategy: fifo
Output queue :0/40 (size/max)
5 minute input rate 0 bits/sec, 0 packets/sec
5 minute output rate 0 bits/sec, 0 packets/sec
0 packets input, 0 bytes, 0 no buffer
Received 0 broadcasts (0 IP multicasts)
0 runts, 0 giants, 0 throttles
0 input errors, 0 CRC, 0 frame, 0 overrun, 0 ignored
0 watchdog, 1017 multicast, 0 pause input
0 input packets with dribble condition detected
0 packets output, 0 bytes, 0 underruns
0 output errors, 0 collisions, 1 interface resets
0 unknown protocol drops
0 babbles, 0 late collision, 0 deferred
0 lost carrier, 0 no carrier
0 output buffer failures, 0 output buffers swapped out
Vlan1 is administratively down, line protocol is down
Hardware is CPU Interface, address is 00d0.9715.9967 (bia 00d0.9715.9967)
MTU 1500 bytes, BW 100000 Kbit, DLY 1000000 usec,
reliability 255/255, txload 1/255, rxload 1/255
Encapsulation ARPA, loopback not set
ARP type: ARPA, ARP Timeout 04:00:00
Last input 21:40:21, output never, output hang never
Last clearing of "show interface" counters never
Input queue: 0/75/0/0 (size/max/drops/flushes); Total output drops: 0
Queueing strategy: fifo
Output queue: 0/40 (size/max)
5 minute input rate 0 bits/sec, 0 packets/sec
5 minute output rate 0 bits/sec, 0 packets/sec
1682 packets input, 530955 bytes, 0 no buffer
Received 0 broadcasts (0 IP multicast)
0 runts, 0 giants, 0 throttles
0 input errors, 0 CRC, 0 frame, 0 overrun, 0 ignored
563859 packets output, 0 bytes, 0 underruns
0 output errors, 23 interface resets
0 output buffer failures, 0 output buffers swapped out
show ip interface
GigabitEthernet0/0/0 is up, line protocol is down (disabled)
Internet address is 1.1.1.1/16
Broadcast address is 255.255.255.255
Address determined by setup command
MTU is 1500 bytes
Helper address is not set
Directed broadcast forwarding is disabled
Outgoing access list is not set
Inbound access list is not set
Proxy ARP is enabled
Security level is default
Split horizon is enabled
ICMP redirects are always sent
ICMP unreachables are always sent
ICMP mask replies are never sent
IP fast switching is disabled
IP fast switching on the same interface is disabled
IP Flow switching is disabled
IP Fast switching turbo vector
IP multicast fast switching is disabled
IP multicast distributed fast switching is disabled
Router Discovery is disabled
IP output packet accounting is disabled
IP access violation accounting is disabled
TCP/IP header compression is disabled
RTP/IP header compression is disabled
Probe proxy name replies are disabled
Policy routing is disabled
Network address translation is disabled
BGP Policy Mapping is disabled
Input features: MCI Check
WCCP Redirect outbound is disabled
WCCP Redirect inbound is disabled
WCCP Redirect exclude is disabled
GigabitEthernet0/0/1 is administratively down, line protocol is down (disabled)
Internet protocol processing disabled
GigabitEthernet0/0/2 is administratively down, line protocol is down (disabled)
Internet protocol processing disabled
Vlan1 is administratively down, line protocol is down
Internet protocol processing disabled
20. At which layer of the OSI model would you assume the problem is if you type
show interface serial 1
and receive the following message?
Serial 1 is down, line protocol is down
physical
if you see both interface and protocal down, it's physical
if you see serial1 is up but line protocol down, its data link- data-link keepalives are not being sent from the remote end
END CHAPTER 6
15 hours 1-15 thru 1-19-22
original total hours 63
2.5 hours review 12-21-22
review total hours 13.5
book page 274/822
Chapter 7 Notes - Managing a Cisco Internetwork
notes
Configuration Register
16 bits / 2 bytes... bit values from 15 to 0
uses Hexadecimal nibbles
Chapter 7 Exam Essentials - Managing a Cisco Internetwork
1. Define the Cisco router componenets
ROM
- used to start and maintain the router. Holds bootstrap, POST, mini-IOS
bootstrap
- stored in the microcode of the ROM. Finds where the IOS program is located and loads the file.
POST
- stored in the microcode of the ROM. Used to check the basic funtionality and determine which interfaces are present
ROM monitor
- stored in the microcode of the ROM. Used for manufacturing, testing, and troubleshooting
mini-IOS
- Called the RXBOOT or 'bootloader'. It's a small OS in ROM that can be used to bring up an interface and load a Cisco IOS into flash memory
-----------------------------------------------------------------------------------------------------------------------
flash memory
- EEPROM- default location of the IOS
NVRAM
-holds the router/switch configuration
not erased when the device is reloaded
configuration register
- controls how the router boots up
Tells the router to load the IOS from flash memory as well as to load the configuration from NVRAM
RAM
- used to hold packet buffers, ARP cache, routing tables and the data structures that allow the router to function.
running-config is stored in RAM
routers expand the IOS from flash into RAM at boot
2. Identify the steps in the router boot sequence
POST
bootstrap
load the IOS from flash into RAM
load the configuration file from NVRAM into RAM
running-config and the IOS are both now running in RAM
3. Understand configuration register commands and settings
0x2102 default- find the boot sequence in NVRAM
0x2101 boot from ROM
0x2142 do not load the startup-config in NVRAM. Used for password recovery
4.Perform password recovery
NOTE - this requires physical access to reboot the router
The default configuration register value is 0x2102 which tells the router to load a config stored
in NVRAM(startup-config).
To recover a password, we need to change the config register value to 0x2142 which tells the router to ignore the VRAM contents and load a 'non configured' OS.
"configurations" can be defined as any changes we make to the device: hostname, passwords, interfaces, etc
For this demo, our 4331 router is configured with the hostname 4331 and the password 1234
4331(config)#
enable secret 1234
4331#
copy run start
Destination filename [startup-config]?
Building configuration...
[OK]
Step 1. Bounce the router, then interrupt the boot sequence by performing a break.
Initializing Hardware ...
Checking for PCIe device presence...done
System integrity status: 0x610
Rom image verified correctly
System Bootstrap, Version 16.7(3r), RELEASE SOFTWARE
Copyright (c) 1994-2018 by cisco Systems, Inc.
Current image running: Boot ROM0
Last reset cause: LocalSoft
Cisco ISR4331/K9 platform with 4194304 Kbytes of main memory
no valid BOOT image found
Final autoboot attempt from default boot device...
Located isr4300-universalk9.16.06.04.SPA.bin
###############################################################
CTRL+BREAK
monitor: command "boot" aborted due to user interrupt
rommon 1 >
Step 2. We're given a ROM MONITOR prompt which allows us to change the configuration register (Cisco ISR/2600 Series commands).
rommon 1 >
confreg 0x2142
rommon 1 >
reset must reset or power cycle router to apply the change
system will ask if you want Setup Mode - that is the the generic startup message,
since we are bypassing the startup configuration. Our answer is no.--- System Configuration Dialog ---
Would you like to enter the initial configuration dialog? [yes/no]:
N + Enter
we now have full access to this non-configured OS. We can enter priviliged mode with no password.
Router>
enable
Router#
show version
Cisco IOS Software [Everest], ISR Software (X86_64_LINUX_IOSD-UNIVERSALK9-M), Version 16.6.4,RELEASE SOFTWARE (fc3)
[cut]
Configuration register is 0x2142
this verifies that our configs are not in use (no hostname in the prompt) and our config register has been changed to 2142
HERE IS THE KEY-
we are going to restore the configuration by copying the "startup-config"
into our live environment AKA the "running-config"
Router#
copy startup-config running-config
Destination filename [running-config]? Enter
695 bytes copied in 0.416 secs (1670 bytes/sec)
4331#
%SYS-5-CONFIG_I: Configured from console by console
we get our old prompt back:
4331#
Note that we DO NOT know the password required to enter privliged mode that we are currently inside of!
if you exit this prompt back out to user mode, you will not be able to get back in without the password.
We entered privileged mode from within the generic configuration. Then inserted our saved configuration 'beneath' our prompt.
This action does not kick you out of priv. mode, which will allow us to RESET the password for our saved configuration.
set the new password
4331(config)#
enable secret 0000
set the config register back to default, to point back to NVRAM on the next reboot
(you can do this from global config mode as well as rommon mode)
4331(config)#
config-register 0x2102
4331#
show version
[cut]
Configuration register is 0x2142 (will be 0x2102 at next reload)
now we can save the config with the updated password.
Two ways to do it-
4331#
write
Building configuration...
[OK]
OR
4331#
copy running-config startup-config
Destination filename [startup-config]?
Building configuration...
[OK]
reload the router and your new password will be saved into your config
4331#
reload
this feature is helpful since Cisco equipment tends to run for long stretches of time (years) and the passwords get forgotten.
Thank you to Jeremy Cioara for help on this topic
5. Back up an IOS image
we can copy a router's configuration to a TFTP server with either of these commands:
Router#
copy running-config tftp
Router#
copy startup-config tftp
to verify either of the configs before backup, we can use these commands:
Router#
show running-config
Router#
show startup-config
6. Restore or upgrade an IOS image - note we are talking about the IOS itself, not the 'configuration'
We will download the IOS file from TFTP server to flash memory on the router. Command requires the IP of the TFTP host and the filename
Before we begin we must make sure the IOS file is in the default TFTP directory on the host.
The command will not ask you where the file is on the host....
Router#
copy tftp flash
Address or name of remote host []? 1.1.1.2
Source filename []? c2800nm-advsecurityk9-mz.124.12.bin
Destination filename[c2800nm-advsecurityk9-mz.124.12.bin]? ENTER
%Warning this is a file already existing with this name
Do you want to over write [confirm] ENTER
Accessing tftp://1.1.1.2/c2800nm-advsecurityk9-mz.124-12.bin...
Loading c2800nm-advsecurityk9-mz.124-12.bin from 1.1.1.2 (via FastEthernet0/0): !!!!!!!!!!!!!!!!
!!!!!!!!!!!!!!!!!!!!!!!!!!
[OK - 21710744 bytes]
21710744 bytes copied in 82.880 secs (261954 bytes/sec)
Router#
to restore configuration:
restore from startup-config:
Router#
copy startup-config running-config
or we can restore from a backup on TFTP server
Router#
copy tftp running-config
Address or name of remote host []? 1.1.1.2
Source filename []? todd-confg
Destination filename[running-config?] ENTER
Accessing tftp://1.1.1.2/todd-confg...
Loading todd-confg from 1.1.12 (civa FastEthernet0/0): !
[OK - 776 bytes]
776 bytes copied in 9.212 secs (84 bytes/sec)
Router#
*Jan 23 12:40:00.000: %SYS-5-CONFIG_I: Configured from tftp://1.1.1.2/todd-confg by console
Router#
7. Describe best practices to prepare to back up an IOS image to a network server
Ensure you can acccess the network server, and there is adequate storage space.
Verify the file naming and path requirements
have the source IOS file in the default TFTP directory
8. Save the configuration of a router
Router#
copy running-config startup-config
9. Erase the configuration of a router
Router#
erase startup-config
10. Understand and use the Cisco IFS file system management commands
IFS = IOS File System
UNIX Based
dir
show files in a directory. Requires privliged mode. If not path is given as argument, you'll see the directory of 'flash' root.
NOTE the file paths use a URL format
R1#
dir
Directory of flash:/
3 -rw- 486899872 <no date> isr4300-universalk9.16.06.04.SPA.bin
2 -rw- 28282 <no date> sigdef-category.xml
1 -rw- 227537 <no date> sigdef-default.xml
3249049600 bytes total (2761893909 bytes free)
-------------------------------------------------------------------------------------------------------
copy
often used to backup, restore, or ugprade the IOS
first arg = source
second arg = destination
R1#
copy
source
destination
-------------------------------------------------------------------------------------------------------
more
display a text file
-------------------------------------------------------------------------------------------------------
show file
display a text file
-------------------------------------------------------------------------------------------------------
delete
remote file (may also need to use SQUEEZE to free up the space)
-------------------------------------------------------------------------------------------------------
erase/format
may delete flash drive depending on system
-------------------------------------------------------------------------------------------------------
cd/pwd
change directory / print working directory
-------------------------------------------------------------------------------------------------------
mkdir/rmdir
create / delete directories
11. Describe the value of CDP
Cisco Discovery Protocol - helps to document / troubleshoot the network
See lab 7.4
12. List the information provided by the output of
show cdp neighbors
device ID
local interface
holdtime
capabilility
platform
port ID (remote interface)
13. Understand how to establish a Telnet session with multiple routers simultaneously
Press Ctrl+Shift+6 then x to exit a telnet session without closing it
14. Identify current Telnet sessions
R1#
show sessions
15. Build a static host table on a router
R1#
ip host
host_name
ip_address
manually assigning an IP to a host name. You can apply multiple IP's to one host entry
see lab 7.6
16. Verify the host table on a router
R1#
show hosts
17. Describe the function of the ping command
Packet Internet Groper uses ICMP echo requests and replies to verify an active IP address on a network
18. Ping a vaild host ID from the correct prompt
R1#
ping 1.1.1.1
Note PING works from user or privliged mode but NOT config mode
Chapter 7 Written Lab 7.1 - IOS Management
TFTP Server Setup - network layout is not from book- I created this network to help demo the written lab
TFTP server is already created and switched on by default within the 'Server' object
Router Configuration
R1(config)#
int g0/0/1
R1(config-if)#
ip address 10.1.1.4 255.255.255.0
R1(config-if)#
no shutdown
%LINK-5-CHANGED: Interface GigabitEthernet0/0/1, changed state to up
%LINEPROTO-5-UPDOWN: Line protocol on Interface GigabitEthernet0/0/1, changed state to up
r1(config-if)#
do show ip int brief
Interface IP-Address OK? Method Status Protocol
GigabitEthernet0/0/0 unassigned YES manual administratively down down
GigabitEthernet0/0/1 192.1.1.4 YES NVRAM up up
GigabitEthernet0/0/2 unassigned YES NVRAM administratively down down
Vlan1 unassigned YES NVRAM administratively down down
Switch Configuration
SW1(config)#
int f0/1
SW1(config-if)#
no shutdown
%LINK-5-CHANGED: Interface FastEthernet0/1, changed state to up
%LINEPROTO-5-UPDOWN: Line protocol on Interface FastEthernet0/1, changed state to up
SW1(config-if)#
int f0/2
SW1(config-if)#
no shutdown
%LINK-5-CHANGED: Interface FastEthernet0/2, changed state to up
%LINEPROTO-5-UPDOWN: Line protocol on Interface FastEthernet0/2, changed state to up
Test connectivity to the server
R1#
ping 192.1.1.3
Type escape sequence to abort.
Sending 5, 100-byte ICMP Echos to 192.1.1.3, timeout is 2 seconds:
.!!!!
Success rate is 80 percent (4/5), round-trip min/avg/max = 0/1/6 ms
Find the name of the Router flash file
R1#
show flash
System flash directory:
File Length Name/status
3 486899872isr4300-universalk9.16.06.04.SPA.bin
2 28282 sigdef-category.xml
1 227537 sigdef-default.xml
[487155691 bytes used, 2761893909 available, 3249049600 total]
3.17338e+06K bytes of processor board System flash (Read/Write)
we need to paste that filename into our copy command below
1. command to copy a Cisco IOS to a TFTP server?
R1#
copy flash tftp
Source filename []? isr4300-universalk9.16.06.04.SPA.bin
Address or name of remote host []? 192.1.1.3
Destination filename [isr4300-universalk9.16.06.04.SPA.bin]? ENTER
Writing isr4300-universalk9.16.06.04.SPA.bin...!!!!!!!!!!!!!!!!
!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!
[OK - 486899872 bytes]
486899872 bytes copied in 12.364 secs (126865 bytes/sec)
the file appears on our server
2. command to copy a Cisco startup-config file to a TFTP server?
R1#
copy running-config tftp
Address or name of remote host []? 192.1.1.3
Destination filename [r1-confg]? ENTER
Writing running-config.....!!
[OK - 707 bytes]
707 bytes copied in 3 secs (235 bytes/sec)
the file appears on our server
OR
R1#
copy startup-config tftp
3. command to copy the startup-config file to DRAM?
R1#
copy startup-config running-config
the running configuration exists in DRAM
4. What is an older command that you can use to copy the startup-config file to DRAM?
R1#
config mem
(not supported by packet tracer)
5. What command can you use to see the neighbor router's IP address from your router prompt?
R1#
show cdp neighbor detail
OR
R1#
show cdp entry *
6. What command to see the hostname, local interface, platform, and remote port of a neighbor router?
R1#
show cdp neighbor
7. What keystrokes can you use to telnet into multiple devices simultaneously?
Ctrl + Shift + 6, then X
8. What command will show you your active Telnet connections to neighbor and remote devices?
R1#
show sessions
9. What command can you use to upgrade a Cisco IOS?
R1#
copy tftp flash
10. What command can you use to merge a backup configuration with the configuration in RAM?
R1#
copy tftp run
OR
R1#
copy start run
RAM = running configuration
Chapter 7 Written Lab 7.2 - Router Memory
Identify the location in a router where each of the files is stored by default:
1. Cisco IOS
flash
2. Bootstrap
ROM
3. Startup configuration
NVRAM
4. POST
ROM
5. Running configuration
RAM
6. ARP cache
RAM
7. Mini IOS
ROM
8. ROM Monitor
ROM
9. Routing tables
RAM
10. packet buffers
RAM
****dont make the mistake of thinking arp cache, routing tables, packet buffers, are stored somewhere other than RAM
they are considered part of running-config which exists in RAM
Chapter 7 Hands-on Labs
To complete these labs, we are going to need three routers and one TFTP server.
Here is the topology:
Server Configuration
ipv4 address: 193.1.1.2
subnet mask: 255.255.255.248
default gateway: 193.1.1.1
Switch Configuration
SW1#
interface range f0/1-2
SW1(config-if-range)#
no shut
Router Configurations
R1(config)#
int g0/0/0
R1(config)#
ip addr 193.1.1.9 255.255.255.248
R1(config)#
no shut
R1(config)#
int g0/0/1
R1(config)#
ip addr 193.1.1.1 255.255.255.248
R1(config)#
no shut
the server's default gateway
R2(config)#
int g0/0/0
R2(config)#
ip addr 193.1.1.10 255.255.255.248
R2(config)#
no shut
R2(config)#
int g0/0/1
R2(config)#
ip addr 193.1.1.17 255.255.255.248
R2(config)#
no shut
R3(config)#
int g0/0/0
R3(config)#
ip addr 193.1.1.18 255.255.255.248
R3(config)#
no shut
the segment between R1 and the server
network 193.1.1.0/29
block of 8
hosts .1, .2
the segment between R1 and R2
network 193.1.1.8/29
block of 8
hosts .9 , .10
the segment between the R2 and R3
network 193.1.1.16/29
block of 8
hosts .17 , .18
THIS IS INCORRECT!!!!
I have misunderstood the instructions.
the problem with this topology is that packets cannot pass through the routers. We dont have any ROUTING setup. ROUTING is covered in the next chapter.
For these labs, we dont need routing, but we need multiple routers to demo telnet and CDP. Here are the instructions:
my mistake was not putting all router interfaces in the same subnet. I tried to do this initially, but it wouldnt work because I had the routers linked together rather than connected by a switch.
The instructions say:
"Your PC and the router(s) are connected together with a switch"
this is the part I missed. The pc and all router interfaces should be on the same switch and the same network
Here is the corrected topology
Server Configuration
ipv4 address: 193.1.1.4
subnet mask: 255.255.255.248
default gateway: 193.1.1.1
Switch Configuration
SW1#
interface range f0/1-4
SW1(config-if-range)#
no shut
Router Configurations
R1(config)#
int g0/0/0
R1(config)#
ip addr 193.1.1.1 255.255.255.248
R1(config)#
no shut
the server's default gateway
R2(config)#
int g0/0/0
R2(config)#
ip addr 193.1.1.2 255.255.255.248
R2(config)#
no shut
R3(config)#
int g0/0/0
R3(config)#
ip addr 193.1.1.3 255.255.255.248
R3(config)#
no shut
Chapter 7 Hands-on Lab 7.1 Backing up your router IOS
1. verify connection to the server
R1#
ping 193.1.1.1
Type escape sequence to abort.
Sending 5, 100-byte ICMP Echos to 193.1.1.2, timeout is 2 seconds:
.!!!!
Success rate is 80 percent (4/5), round-trip min/avg/max = 0/1/5 ms
2. show contents of flash memory
R1#
show flash
System flash directory:
File Length Name/status
3 486899872isr4300-universalk9.16.06.04.SPA.bin
2 28282 sigdef-category.xml
1 227537 sigdef-default.xml
[487155691 bytes used, 2761893909 available, 3249049600 total]
3.17338e+06K bytes of processor board System flash (Read/Write)
show flash gives ALL of the files in flash memory
show version gives the current running file
3. show the IOS currently running
R1#
show version
Cisco IOS XE Software, Version 03.16.05.S - Extended Support Release
[cut]
ROM: IOS-XE ROMMON
Router uptime is 9 minutes, 39 seconds
Uptime for this control processor is 9 minutes, 39 seconds
System returned to ROM by power-on
System image file is "bootflash:/isr4300-universalk9.03.16.05.S.155-3.S5-ext.SPA.bin"
Last reload reason: PowerOn
[cut]
note that the file that is currently running is NOT located in the flash storage!!!
4. backup IOS from router to server
R1#
copy flash tftp
Source filename []?isr4300-universalk9.16.06.04.SPA.bin
Address or name of remote host []? 193.1.1.4
Destination filename [isr4300-universalk9.16.06.04.SPA.bin]? ENTER
Writing isr4300-universalk9.16.06.04.SPA.bin...!!!!!!!!!!!!!!!
[OK - 486899872 bytes]
486899872 bytes copied in 12.526 secs (125224 bytes/sec)
Chapter 7 Hands-on Lab 7.2 Upgrading or restoring your router IOS
1. verify connection to the server
R1#
ping 193.1.1.4
Type escape sequence to abort.
Sending 5, 100-byte ICMP Echos to 193.1.1.2, timeout is 2 seconds:
!!!!!
Success rate is 100 percent (5/5), round-trip min/avg/max = 0/0/1 ms
2. copy from tftp sever to flash
R1#
copy tftp flash TFTP comes first in the command since we are pulling from TFTP server.
In this command, remot host address is required before file name
Address or name of remote host []? 193.1.1.4
Source filename []?isr4300-universalk9.16.06.04.SPA.bin
Destination filename [isr4300-universalk9.16.06.04.SPA.bin]? ENTER
%Warning:There is a file already existing with this name
Do you want to over write? [confirm]
Accessing tftp://193.1.1.4/isr4300-universalk9.16.06.04.SPA-12-23-22...
Loading isr4300-universalk9.16.06.04.SPA-12-23-22.bin from 193.1.1.4: !!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!
[OK - 486899872 bytes]
486899872 bytes copied in 12.785 secs (122688 bytes/sec)
Chapter 7 Hands-on Lab 7.3 Backing up the router configuration
1. verify connection to the server
R1#
ping 193.1.1.2
Type escape sequence to abort.
Sending 5, 100-byte ICMP Echos to 193.1.1.4, timeout is 2 seconds:
!!!!!
Success rate is 100 percent (5/5), round-trip min/avg/max = 0/0/1 ms
2. copy running-confing to server
R1#
copy run tftp
Address or name of remote host []? 193.1.1.4
Destination filename [R1-confg]?ENTER "R1-confg" is the default name
Writing running-config...!!
[OK - 668 bytes]
668 bytes copied in 0.004 secs (167000 bytes/sec)
Chapter 7 Hands-on Lab 7.4 Using the Cisco Discovery Protocol (CDP)
R1#
show cdp
Global CDP information:
Sending CDP packets every 60 seconds
Sending a holdtime value of 180 seconds
Sending CDPv2 advertisements is enabled
R1#
show cdp interface
Vlan1 is administratively down, line protocol is down
Sending CDP packets every 60 seconds
Holdtime is 180 seconds
GigabitEthernet0/0/0 is up, line protocol is up
Sending CDP packets every 60 seconds
Holdtime is 180 seconds
GigabitEthernet0/0/1 is administratively down, line protocol is down
Sending CDP packets every 60 seconds
Holdtime is 180 seconds
GigabitEthernet0/0/2 is administratively down, line protocol is down
Sending CDP packets every 60 seconds
Holdtime is 180 seconds
R1#
show cdp entry *
Device ID: SW1
Entry address(es):
Platform: cisco 2960, Capabilities: Switch
Interface: GigabitEthernet0/0/0, Port ID (outgoing port): FastEthernet0/1
NOTE g0/0/0 is the outgoing port on this router, F0/1 is the port on the switch at other end
Holdtime: 157
Version :
Cisco IOS Software, C2960 Software (C2960-LANBASEK9-M), Version 15.0(2)SE4, RELEASE SOFTWARE (fc1)
Technical Support: http://www.cisco.com/techsupport
Copyright (c) 1986-2013 by Cisco Systems, Inc.
Compiled Wed 26-Jun-13 02:49 by mnguyen
advertisement version: 2
Duplex: full
R1#
show cdp entry neighbors
[no output]
R1#
show cdp neighbors detail
Device ID: SW1
Entry address(es):
Platform: cisco 2960, Capabilities: Switch
Interface: GigabitEthernet0/0/0, Port ID (outgoing port): FastEthernet0/1
Holdtime: 178
Version :
Cisco IOS Software, C2960 Software (C2960-LANBASEK9-M), Version 15.0(2)SE4, RELEASE SOFTWARE (fc1)
Technical Support: http://www.cisco.com/techsupport
Copyright (c) 1986-2013 by Cisco Systems, Inc.
Compiled Wed 26-Jun-13 02:49 by mnguyen
advertisement version: 2
Duplex: full
Chapter 7 Hands-on Lab 7.5 Using Telnet
enable telnet on R2 and set password
R2(config)#
line vty 0 15
R2(config-line)#
password telnet
R2(config-line)#
login
enable telnet on R3 and set password
R3(config)#
line vty 0 15
R3(config-line)#
password telnet
R3(config-line)#
login
note that the result of this command on each router, by default,
is to present all 15 lines in TWO SEPERATE chunks: 0-4 and 5-15
R3#
show run
[cut]
!
!
!
line con 0
!
line aux 0
!
line vty 0 4
password telnet
login
line vty 5 15
password telnet
login
!
!
!
end
--------------------------------------------------------------------------------
connect to R2 from R1
R1#
telnet 193.1.1.2
Trying 193.1.1..2 ...Open
User Access Verification
Password: telnet
prompt changes to R2 to indicate we are remoted in
R2>
exit the session
ctrl + shift + 6, x
prompt changes back to R1
R1#
--------------------------------------------------------------------------------
connect to R3 from R1
R1#
193.1.1.3 note that the word 'telnet' is not required bc we are still in telnet mode
Trying 193.1.1..3 ...Open
User Access Verification
Password: telnet
prompt changes to R3 to indicate we are remoted in
R3>
exit the session
ctrl + shift + 6, x
prompt changes back to R1
R1#
--------------------------------------------------------------------------------
We have exited the sessions, but they are still open
R1#
show sessions
Conn Host Address Byte Idle Conn Name
1 193.1.1.2 193.1.1.2 0 0 193.1.1.2
* 2 193.1.1.3 193.1.1.3 0 0 193.1.1.3
two telnet sessions- notice that the 'conn number' doesnt correspond to ip address in any way.
R1#
show users
Line User Host(s) Idle Location
* 0 con 0 193.1.1.2 00:00:03
193.1.1.3 00:00:43
this is saying one user is on this router, with two outbound connections (but it isnt showing that they are vty connections)
... they must both be considered 'console' connections outbound and are not considered 'vty' until they are received inbound
the asterisk means something different here than above... doesnt mean default(most recent)session... what does it mean?
back to R2
R2#
show users
Line User Host(s) Idle Location
* 4 vty 0 idle 00:00:00 193.1.1.1
Interface User Mode Idle Peer Address
this is saying that there is one (unnamed) user remoted in via line vty 4
back to R3
R3#
show users
Line User Host(s) Idle Location
* 4 vty 0 idle 00:00:00 193.1.1.1
Interface User Mode Idle Peer Address
this is saying that there is one (unnamed) user remoted in via line vty 4
-------------------------------------------------------------------------------------
Important Considerations:
-
asterisk indicates default session
-
when telnetting in, you will be in user mode. If there is no password already set for PRIVILEGED MODE, you will be unable to enter
-
be careful with 'exit'. it will exit the telnet session if you exit at priv. mode. Use 'disable' to leave priv mode.
-
after 'suspending' a session with ctrl+shift+6,x and youre back at your original priv. prompt, do not press enter to create line breaks-
rather than break lines as usual, the keystroke will cause this:
[Resuming connection 1 to 193.1.1.2 ... ]
prompt will sit here until you strike enter again, then you'll return to that session. What is actually happening is that
youre connecting to the 'default' telnet connection. The same behavior happens when youre at the 'show sessions' screen.
Even if you are not viewing active sessions, the enter key(twice) will connect you to the default session
-
you can use disconnect or exit to end a session
-
Ex: disconnect 1 at the show sessions screen
Chapter 7 Hands-on Lab 7.6 Resolving Hostnames
We're going to build a host table on R1 so we can connect to the other routers via hostname rather than type in the IP address
the command is ip host name arg ip arg
R1(config)#
ip host R2 193.1.1.2
R1(config)#
ip host R3 193.1.1.3
Now if we enter R2 or telnet R2 we get the telnet prompt
R1# R2
Trying 193.1.1.2 ...Open
User Access Verification
Password:
same for the PING command
R1# ping R2
Type escape sequence to abort.
Sending 5, 100-byte ICMP Echos to 193.1.1.2, timeout is 2 seconds:
!!!!!
Success rate is 100 percent (5/5), round-trip min/avg/max = 0/0/2 ms
R1#
show hosts
Default Domain is not set
Name/address lookup uses domain service
Name servers are 255.255.255.255
Codes: UN - unknown, EX - expired, OK - OK, ?? - revalidate
temp - temporary, perm - permanent
NA - Not Applicable None - Not defined
Host Port Flags Age Type Address(es)
R2 None (perm, OK) 0 IP 193.1.1.2
R3 None (perm, OK) 0 IP 193.1.1.3
R1#
telnet R2
R2>
CTRL + SHIFT + 6, X
R1#
telnet R3
R3>
CTRL + SHIFT + 6, X
R1#
show session
Conn Host Address Byte Idle Conn Name
1 R2 193.1.1.2 0 0 R2
* 2 R3 193.1.1.3 0 0 R3
Chapter 7 Review Questions
1. What does the command
confreg 0x2142
provide?
bypass startup-config, to allow password reset
2. Which command will copy the IOS to a backup host on your network?
copy flash tftp
3. You are troubleshooting a connectivity problem in your corporate network and want to isolate the problem. You suspect that a router on the route to an unreachable
network is at fault. What IOS user exec command should you issue?
traceroute
note this is not a priviliged mode command; it can be run from user mode
4. You copy a configuration from a network host to a router's RAM. The configuration looks correct, yet it is no working at all. What could the problem be?
when you perform a copy from a network host to a router, the interfaces are automatically shut down and have to be manually enabled with no shutdown
5. A network administrator wants to upgrade the IOS of a router without removing the image currently installed. What command will display the amount of memory consumed by the
current IOS image and indicate whether there is enough room available to hold both the current and new images?
show flash
6. The corporate office sends you a new router to connect, but upon connecting the console cable, you see that there is already a configuration on the router.
What should be done before a new configuration is entered in the router?
erase NVRAM and restart the router
erase startup-config
reload
7. Which command loads a new version of the Cisco IOS into a router?
copy tftp flash
8. Which command will show you the IOS version running on your router?
show version
9. What should the configuration register value be after you successfully complete the password recovery procedure and return the router to normal operation?
0x2102
10. You save the configuration on a router with the
copy running-config startup-config
command and reboot the router. The router, however, comes up with a blank configuration. What can the problem be?
wrong config register causing you to bypass startup-confing in NVRAM
11. If you want to have more than one Telnet session open at the same time, what keystroke combination would you use?
CTRL+SHIFT+6, X
12. You are unsuccessful in telnetting into a remote device, but you could telnet to the router earlier, However, you can still ping the remote device.
What can the problem be?
access control list could be filtering telnet
OR
the VTY password may not be set on the target
13. What information is displayed by the
show hosts
command?
gives info on temporary DNS entries and permanent name-to-address mappings created using the ip host command
14. Name three commands that can be used to check LAN connectivity problems on a router?
trace
show interfaces
show ip route
15. You telnet to a router and make your necessary changes; now you want to end the Telnet session. What command do you type in?
exit
16. You telnet into a remote device and type
debug ip rip
but no output from the
debug
command is seen. What could the problem be?
to see console messages through a telnet session, you must enter the command terminal monitor
17. Which command displays the configuration register setting?
show version
18. You need to gather the IP address of a remote switch that is located in Hawaii. What can you do to find the address?
show cdp neighbors detail
19. You have your laptop directly connected into a router's Ethernet port. Which are requirements for the
copy flash tftp
command to be successful?
have a TFTP server running on the laptop
laptop must have an IP on the same subnet as the router interface
give the IP address of the laptop when asked after entering the command
20. The configuration register setting of 0x2102 provides what function to a router?
points to NVRAM for startup-configuration AND boot sequence
END CHAPTER 7
26 hours 1-19 thru 1-26-22
original total hours 89
7 hours review 12-23-22
review total hours 20.5
book page 344/822
avg 15 min/page (reading and exercises/labs)
Chapter 8 Exercises
pg 374
before I begin to configure this network, I want to look closer at the HARDWARE
Todd mentions these routers:
2811 with four serial interfaces and switch module or wireless card
1841
while the book was published in 2011, both routers appear to be available in 2021 packet tracer,
but both are considered legacy as of Feb 2022.
The 2811:
The 1841:
we're going to need to understand the MODULES. What are these?
a few examples:
NM-1E is a 1-port ethernet module
NM-1FE-TX is a fast ethernet module
NM-8A/s is an Eight Port Async/Sync Network Module
HWIC-2T is a 2-port serial WAN interface card
HWIC-AP-AG-B is a wireless card
What is an "NM module"?
A network module is a software module that implements a specific
function in a network stack, such as a data link interface, a transport protocol,
or a network application.
What is a "HWIC module"?
A high-speed WAN interface card
Here is a look inside a real 2811:
Back to the requirements for our lab- Todd says the 2811 'Corp' router needs a switch module
and four serial interfaces. NOTE the book doesnt give specifics on how to create the topology in Packet Tracer.
Our Packet Tracer 2811 offers these modules:
The NM-ESW-16 appears to be the only 'switch module', so I will add that.
And the HWIC-2T is a 2-Port Serial High-Speed WAN Interface Card, providing 2 serial ports.
I will add two of these.
next: R3, which needs to be a 2811 with a wirless card. I will add the HWIC-AP-AG-B:
The HWIC-AP-AG-B module is a High-Speed WAN Interface Card providing integrated Access Point
functionality in the Cisco 1800 (Modular), Cisco 2800,
and Cisco 3800 Integrated Services Routers.
It supports Single Band 802.11b/g or Dual Band 802.11a/b/g radios.
our router hardware is in place:
and here is where we need to end up
Next we need to figure out how to connect the server farm to the switch card on R1:
if I use the auto-select cable, I get a copper crossover cable connecting at fa0/0 on the router.
Per the diagram fa0/0 should
connect to R3. I need to connect the servers to the switch card on R1.
Instead of using the auto-select cable, I'll try a straight-through cable.
Success. While the auto-select cable did not give me an option as to what port it will connect to, I did get the option when
manually applying the straight-through cable. Instead of connecting to F0/0 which would require a crossover-cable(computer to router),
I will connect to the integrated switch at port F1/0, then connect the other two servers to F1/1 and F1/2, respectively.
Also worth noting: the Physical Device diagrams in Packet Tracer do not show cables plugged into the ports.
We are relying on the labels on the logical diagram to see which cables are plugged into which ports...
As far as how we can tell what is connected from within the CLI.. I dont know right now.
Now I will connect the other routers. Here is the chart specifiying what interfaces should be used:
Router
Network Address
Interface
Address
CORP
10.1.1.0
Vlan1 (switch card)
10.1.1.1
10.1.2.0
S0/0/0
10.1.2.1
10.1.3.0
S0/0/1 (DCE)
10.1.3.1
10.1.4.0
S0/1/0
10.1.4.1
10.1.5.0
F0/0
10.1.5.1
R1
10.1.2.0
S0/0/0 (DCE)
10.1.2.2
10.1.3.0
S0/0/1
10.1.3.2
192.168.10.0
F0/0
192.168.10.1
192.168.20.0
F0/1
192.168.20.1
R2
10.1.4.0
S0/0/0 (DCE)
10.1.4.2
192.168.30.0
F0/0
192.168.30.1
192.168.40.0
F0/0
192.168.40.1
R3
10.1.5.0
F0/0
10.1.5.2
172.16.10.0
Dot11Radio0/0/0
172.16.10.1
PROBLEM
The R1 router doesnt appear to have any serial interfaces
I will add an HWIC-2T card to both R1 and R2 since the diagram calls for serial interfaces.
The HWIC-2T is a Cisco 2-Port Serial High-Speed WAN Interface Card, providing 2 serial ports.
PROBLEM
The Corp router is not showing the expected available interfaces. I need to connect R1 to the S0/0/0 interface on Corp and R2 to the S0/0/1 interface on Corp.
My Corp router is not showing those interfaces:
Solution
the placement of the cards on the router determines which interface numbers will be available.
In this case, it seems the interfaces start from the bottom right corner and increase on each slot moving clockwise. I found this out by filling all four slots on my router
which led to all interfaces being available. I then ran a card in each slot individually to isolate which interface numbers correspond to each slot:
Interestingly, while the physical slots seem to follow a 'clockwise' pattern, the list of available slots in the logical diagram does not;
We get an output of interfaces corresponding to slot 2, then 3, 1, and 4. This is a 'bottom to top' then 'left to right' pattern. Tricky.
Having said all that... I will run cards in slots 1 and 2 for this lab since we only need interfaces S0/0/0, S0/0/1, S0/1/0
The Router topology:
I'm not clear on the connections from R1 and R2 to the clients.. I assume there are switches involved.
For now I will follow the next steps in the book which
are to configure the corp router as follows:
Router(config)#
hostname Corp
Corp(config)#
enable secret todd
Corp(config)#
interface vlan 1
Corp(config-if)#
description Switch Card to Core Network
Corp(config-if)#
ip address 10.1.1.1 255.255.255.0
Corp(config-if)#
no shut
----------------------------------------------------------------------------------------------------------------
Corp(config-if)#
int f1/0
Corp(config-if)#
description Switch Port connection to WWW Server
Corp(config-if)#
no shutdown
Corp(config-if)#
int f1/1
Corp(config-if)#
description Switch Port connection to Email Server
Corp(config-if)#
no shutdown
Corp(config-if)#
int f1/2
Corp(config-if)#
description Switch Port connection to DNS Server
Corp(config-if)#
no shutdown
----------------------------------------------------------------------------------------------------------------
Corp(config-if)#
int s0/0/0
Corp(config-if)#
description 1st Connection to R1
Corp(config-if)#
ip address 10.1.2.1 255.255.255.0
Corp(config-if)#
no shut
Corp(config-if)#
int s0/0/1
Corp(config-if)#
description 2nd Connection to R1
Corp(config-if)#
ip address 10.1.3.1 255.255.255.0
Corp(config-if)#
no shut
Corp(config-if)#
int s0/1/0
Corp(config-if)#
description Connection to R2
Corp(config-if)#
ip address 10.1.4.1 255.255.255.0
Corp(config-if)#
no shut
Corp(config-if)#
int fa0/0
Corp(config-if)#
description Connection to R3
Corp(config-if)#
ip address 10.1.5.1 255.255.255.0
Corp(config-if)#
no shut
----------------------------------------------------------------------------------------------------------------
Corp(config-if)#
line con 0
Corp(config-if)#
password console
Corp(config-if)#
login
Corp(config-if)#
logging synchro
Corp(config-if)#
exec-timeout 0 0
----------------------------------------------------------------------------------------------------------------
Corp(config-if)#
line aux 0
Corp(config-if)#
password aux
Corp(config-if)#
login
Corp(config-if)#
exit
----------------------------------------------------------------------------------------------------------------
Corp(config)#
line vty ?
<1-15>Last Line number
Corp(config)#
line vty 0 15
Corp(config-if)#
password telnet
Corp(config-if)#
login
Corp(config-if)#
exit
----------------------------------------------------------------------------------------------------------------
Corp(config)#
no ip domain lookup
Corp(config)#
banner motd # This is my Corp 2811 ISR Router #
Ctrl + Z
%SYS-5-CONFIG_I: Configured from console by console
(Ctrl-Z: When in a config mode, ends the config mode and returns you to privileged EXEC mode.... same as typing exit(?))
Corp#
copy run start
Destination filename [startup-config]?
Building configuration...
[OK]
----------------------------------------------------------------------------------------------------------------
Corp#
show ip int br
Interface IP-Address OK? Method Status Protocol
FastEthernet0/0 10.1.5.1 YES manual up down
FastEthernet0/1 unassigned YES unset administratively down down
Serial0/0/0 10.1.2.1 YES manual down down
Serial0/0/1 10.1.3.1 YES manual down down
Serial0/1/0 10.1.4.1 YES manual down down
Serial0/1/1 unassigned YES unset administratively down down
FastEthernet1/0 unassigned YES unset up up
FastEthernet1/1 unassigned YES unset up up
FastEthernet1/2 unassigned YES unset up up
FastEthernet1/3 unassigned YES unset administratively down down
FastEthernet1/4 unassigned YES unset administratively down down
FastEthernet1/5 unassigned YES unset administratively down down
FastEthernet1/6 unassigned YES unset administratively down down
FastEthernet1/7 unassigned YES unset administratively down down
FastEthernet1/8 unassigned YES unset administratively down down
FastEthernet1/9 unassigned YES unset administratively down down
FastEthernet1/10 unassigned YES unset administratively down down
FastEthernet1/11 unassigned YES unset administratively down down
FastEthernet1/12 unassigned YES unset administratively down down
FastEthernet1/13 unassigned YES unset administratively down down
FastEthernet1/14 unassigned YES unset administratively down down
FastEthernet1/15 unassigned YES unset administratively down down
Vlan1 10.1.1.1 YES manual up up
----------------------------------------------------------------------------------------------------------------
Corp#
show run
Building configuration...
Current configuration : 2073 bytes
!
version 15.1
no service timestamps log datetime msec
no service timestamps debug datetime msec
no service password-encryption
!
hostname Corp
!
!
!
enable secret 5 $1$mERr$V5ujdIM9bTB/I.ipB0gkJ0
!
!
!
!
!
!
no ip cef
no ipv6 cef
!
!
!
!
license udi pid CISCO2811/K9 sn FTX1017U440-
!
!
!
!
!
!
!
!
!
no ip domain-lookup
!
!
spanning-tree mode pvst
!
!
!
!
!
!
interface FastEthernet0/0
description connection to R3
ip address 10.1.5.1 255.255.255.0
duplex auto
speed auto
!
interface FastEthernet0/1
no ip address
duplex auto
speed auto
shutdown
!
interface Serial0/0/0
description 1st connection to R1
ip address 10.1.2.1 255.255.255.0
clock rate 2000000
!
interface Serial0/0/1
description 2nd connection to R1
ip address 10.1.3.1 255.255.255.0
clock rate 2000000
!
interface Serial0/1/0
description connection to R2
ip address 10.1.4.1 255.255.255.0
!
interface Serial0/1/1
no ip address
clock rate 2000000
shutdown
!
interface FastEthernet1/0
description switch port connection to WWW Server
!
interface FastEthernet1/1
description switch port connection to Email Server
!
interface FastEthernet1/2
description switch port connection to DNS Server
!
interface FastEthernet1/3
shutdown
!
interface FastEthernet1/4
shutdown
!
interface FastEthernet1/5
shutdown
!
interface FastEthernet1/6
shutdown
!
interface FastEthernet1/7
shutdown
!
interface FastEthernet1/8
shutdown
!
interface FastEthernet1/9
shutdown
!
interface FastEthernet1/10
shutdown
!
interface FastEthernet1/11
shutdown
!
interface FastEthernet1/12
shutdown
!
interface FastEthernet1/13
shutdown
!
interface FastEthernet1/14
shutdown
!
interface FastEthernet1/15
shutdown
!
interface Vlan1
description Switch Card to Core Network
ip address 10.1.1.1 255.255.255.0
!
ip classless
!
ip flow-export version 9
!
!
!
banner motd ^C This is my Corp 2811 ISR Router ^C
!
!
!
!
!
line con 0
exec-timeout 0 0
password console
logging synchronous
login
!
line aux 0
password aux
login
!
line vty 0 4
password telnet
login
line vty 5 15
password telnet
login
!
!
!
end
-----------------------------------------------------------------------------------------------------------------------
more configurations:
R1
Router(config)#
hostname R1
R1(config)#
enable secret todd
R1(config)#
int s0/0/0
R1(config-if)#
ip address 10.1.2.2 255.255.255.0
R1(config-if)#
Decription 1st connection to corp router
R1(config-if)#
no shut
-----------------------------------------------------------------------------------------------
R1(config-if)#
int s0/0/1
R1(config-if)#
ip address 10.1.3.2 255.255.255.0
R1(config-if)#
Decription 2nd connection to corp router
R1(config-if)#
no shut
-----------------------------------------------------------------------------------------------
R1(config-if)#
int f0/0
R1(config-if)#
ip address 192.168.10.1 255.255.255.0
R1(config-if)#
Decription connection to finance
R1(config-if)#
no shut
-----------------------------------------------------------------------------------------------
R1(config-if)#
int f0/1
R1(config-if)#
ip address 192.168.20.1 255.255.255.0
R1(config-if)#
Decription connection to marketing
R1(config-if)#
no shut
R1(config-if)#
exit
-----------------------------------------------------------------------------------------------
R1(config)#
line con 0
R1(config-line)#
password console
R1(config-line)#
login
R1(config-line)#
logging synchronous
R1(config-line)#
exec-timeout 0 0
-----------------------------------------------------------------------------------------------
R1(config-line)#
line aux 0
R1(config-line)#
password aux
R1(config-line)#
login
R1(config-line)#
exit
-----------------------------------------------------------------------------------------------
R1(config)#
line vty 0 ?
<0-15> Last Line number
R1(config)#
line vty 0 807
R1(config-line)#
password telnet
R1(config-line)#
login
R1(config-line)#
banner motd # This is my R1 Router #
R1(config-line)#
exit
-----------------------------------------------------------------------------------------------
R1(config)#
no ip domain-lookup
R1(config)#
exit
R1#
copy run start
R2
Router(config)#
hostname R2
R2(config)#
enable secret todd
R2(config)#
int s0/0/0
R2(config-if)#
ip address 10.1.4.2 255.255.255.0
R2(config-if)#
description connection to corp router
R2(config-if)#
no shut
-----------------------------------------------------------------------------------------------
R2(config-if)#
int f0/0
R2(config-if)#
ip address 192.168.30.1 255.255.255.0
R2(config-if)#
description connection to sales PC
R2(config-if)#
no shut
-----------------------------------------------------------------------------------------------
R2(config-if)#
int f0/1
R2(config-if)#
ip address 192.168.40.1 255.255.255.0
R2(config-if)#
description connection to HR pc
R2(config-if)#
no shut
-----------------------------------------------------------------------------------------------
R2(config-if)#
line con 0
R2(config-line)#
password console
R2(config-line)#
login
R2(config-line)#
logging synchronous
R2(config-line)#
exec-timeout 0 0
-----------------------------------------------------------------------------------------------
R2(config-line)#
line aux 0
R2(config-line)#
password aux
R2(config-line)#
login
R2(config-line)#
exit
-----------------------------------------------------------------------------------------------
R2(config)#
line vty 0 ?
<0-15> Last Line number
R2(config)#
line vty 0 807
R2(config-line)#
password telnet
R2(config-line)#
login
R2(config-line)#
banner motd # This is my R1 Router #
R2(config-line)#
exit
-----------------------------------------------------------------------------------------------
R2(config)#
no ip domain-lookup
R2(config)#
exit
R2#
copy run start
R3
Router(config)#
hostname R3
R3(config)#
enable secret todd
R3(config)#
int f0/0
R3(config-if)#
ip address 10.1.5.2 255.255.255.0
R3(config-if)#
description connection to corp router
R3(config-if)#
no shut
-----------------------------------------------------------------------------------------------
R3(config-if)#
int dot11radio0/0/0
R3(config-if)#
ip address 172.16.10.1 255.255.255.0
R3(config-if)#
description WLAN for mobile user
R3(config-if)#
no shut
R3(config-if)#
ssid ADMIN
stuck here 2-5-22-- packet tracer isnt taking me into the config-if-ssid prompt
R3(config-if-ssid)#
guest-mode
R3(config-if-ssid)#
authentication open
R3(config-if-ssid)#
ingrastructure-ssid
R3(config-if-ssid)#
exit
-----------------------------------------------------------------------------------------------
R3(config-if)#
line con 0
R3(config-line)#
password console
R3(config-line)#
login
R3(config-line)#
logging synchronous
R3(config-line)#
exec-timeout 0 0
-----------------------------------------------------------------------------------------------
R3(config-line)#
line aux 0
R3(config-line)#
password aux
R3(config-line)#
login
R3(config-line)#
exit
-----------------------------------------------------------------------------------------------
R3(config)#
line vty 0 ?
<0-15> Last Line number
R3(config)#
line vty 0 807
R3(config-line)#
password telnet
R3(config-line)#
login
R3(config-line)#
banner motd # This is my R1 Router #
R3(config-line)#
exit
-----------------------------------------------------------------------------------------------
R3(config)#
no ip domain-lookup
R3(config)#
exit
R3#
copy run start
PROBLEM
i cant get into conf-if-ssid prompt
R3(config-if)#
ssid ADMIN
%LINK-5-CHANGED: Interface Dot11Radio0/0/0, changed state to administratively down
%LINEPROTO-5-UPDOWN: Line protocol on Interface Dot11Radio0/0/0, changed state to down
%LINK-5-CHANGED: Interface Dot11Radio0/0/0, changed state to up
%LINEPROTO-5-UPDOWN: Line protocol on Interface Dot11Radio0/0/0, changed state to up
R3(config-if)#
research led me to this thread, which is a dead end:
further research led me here:
R3(config)# global config mode
R3(config)#
dot11 ssid ADMIN
creates an SSID or lets you config an existing SSID
R3(config-ssid)#
guest-mode
R3(config-ssid)#
%LINK-5-CHANGED: Interface Dot11Radio0/0/0, changed state to administratively down
%LINEPROTO-5-UPDOWN: Line protocol on Interface Dot11Radio0/0/0, changed state to down
%LINK-5-CHANGED: Interface Dot11Radio0/0/0, changed state to up
%LINEPROTO-5-UPDOWN: Line protocol on Interface Dot11Radio0/0/0, changed state to up
R3(config-ssid)#
authentication open
R3(config-ssid)#
%LINK-5-CHANGED: Interface Dot11Radio0/0/0, changed state to administratively down
%LINEPROTO-5-UPDOWN: Line protocol on Interface Dot11Radio0/0/0, changed state to down
%LINK-5-CHANGED: Interface Dot11Radio0/0/0, changed state to up
%LINEPROTO-5-UPDOWN: Line protocol on Interface Dot11Radio0/0/0, changed state to up
R3(config-ssid)#
infrastructure-ssid
R3(config-ssid)#infrastructure-ssid
^
% Invalid input detected at '^' marker.
this command given by the book doesnt appear to be valid
R3(config-ssid)#
?
authentication authentication method
exit Exit from ssid sub mode
guest-mode guest ssid
no Negate a command or set it's defaults
wpa-psk Configure Wi-Fi Protected Access pre-shared key
back into the interface to see what the options are
R3(config-ssid)#
int dot110/0/0
R3(config-if)#
?
arp Set arp type (arpa, probe, snap) or timeout or log options
bandwidth Set bandwidth informational parameter
cdp CDP interface subcommands
crypto Encryption/Decryption commands
delay Specify interface throughput delay
description Interface specific description
encryption Configure dot11 encryption parameters
exit Exit from interface configuration mode
fair-queue Enable Fair Queuing on an Interface
hold-queue Set hold queue depth
ip Interface Internet Protocol config commands
mac-address Manually set interface MAC address
mtu Set the interface Maximum Transmission Unit (MTU)
no Negate a command or set its defaults
priority-group Assign a priority group to an interface
service-policy Configure QoS Service Policy
shutdown Shutdown the selected interface
speed Set allowed radio bit rates
ssid Configure radio service set parameters
tx-ring-limit Configure PA level transmit ring limit
i'll consider the problem *mostly* solved. I was able to assign the SSD.
The infrastructure command may be expendable in this case... to be determined
here is our configuration for R3
R3#
show run
Building configuration...
Current configuration : 1682 bytes
!
version 15.1
no service timestamps log datetime msec
no service timestamps debug datetime msec
no service password-encryption
!
hostname R3
!
!
!
enable secret 5 $1$mERr$V5ujdIM9bTB/I.ipB0gkJ0
!
!
ip dhcp excluded-address 172.16.10.1 172.16.10.10
!
ip dhcp pool Admin
network 172.16.10.0 255.255.255.0
default-router 172.16.10.1
!
dot11 ssid ADMIN
authentication open
guest-mode
!
dot11 ssid ADMIN2
authentication open
guest-mode
!
!
!
ip cef
no ipv6 cef
!
!
!
!
license udi pid CISCO2811/K9 sn FTX1017RE40-
!
!
!
!
!
!
!
!
!
no ip domain-lookup
ip name-server 172.16.10.4
!
!
spanning-tree mode pvst
!
!
!
!
!
!
interface FastEthernet0/0
description connection to corp router
ip address 10.1.5.2 255.255.255.0
duplex auto
speed auto
!
interface FastEthernet0/1
no ip address
duplex auto
speed auto
shutdown
!
interface Dot11Radio0/0/0
description WAN for mobile
ip address 172.16.10.1 255.255.255.0
speed 12.0 18.0 24.0 36.0 48.0 54.0 6.0 9.0 basic-1.0 basic-11.0 basic-2.0 basic-5.5
ssid ADMIN2
!
interface Dot11Radio0/0/1
no ip address
speed 18.0 36.0 48.0 54.0 9.0 basic-12.0 basic-24.0 basic-6.0
!
interface Serial0/1/0
no ip address
clock rate 2000000
!
interface Serial0/1/1
no ip address
clock rate 2000000
!
interface Vlan1
no ip address
shutdown
!
router rip
version 2
network 10.0.0.0
network 172.16.0.0
!
ip classless
ip route 0.0.0.0 0.0.0.0 10.1.5.1
!
ip flow-export version 9
!
!
!
banner motd ^C this is R3 $
this is R3 ^C
!
!
!
!
!
line con 0
exec-timeout 0 0
password console
logging synchronous
login
!
line aux 0
password aux
login
!
line vty 0 4
password telnet
login
line vty 5 15
password telnet
login
!
!
!
end
to summarize...
the book is a little off here.
-----------------------------------------------------------------------------------------------
R3(config-if)#
int dot11radio0/0/0
R3(config-if)#
ip address 172.16.10.1 255.255.255.0
R3(config-if)#
description WLAN for mobile user
R3(config-if)#
no shut
at this point we have created a wireless interface with an IP address but no SSID exists on this router
interface Dot11Radio0/0/0
description test router 2
ip address 172.16.10.1 255.255.255.0
speed 12.0 18.0 24.0 36.0 48.0 54.0 6.0 9.0 basic-1.0 basic-11.0 basic-2.0 basic-5.5
Trying to use the command "ssid ADMIN" doesnt work here. The below commands are invalid here:
R3(config-if)#
ssid ADMIN
R3(config-if-ssid)#
guest-mode
R3(config-if-ssid)#
authentication open
R3(config-if-ssid)#
ingrastructure-ssid
R3(config-if-ssid)#
exit
-----------------------------------------------------------------------------------------------
We need to drop out of config-if, back to config, and enter SSID config mode
-----------------------------------------------------------------------------------------------
R3(config-if)#
exit
R3(config)#
dot11 ssid ADMIN2 creates an ssid named ADMIN2, and puts us into SSID config mode
R3(config-ssid)#
guest-mode
R3(config-ssid)#
authentication open
then out of config-ssid and back to interface config
R3(config-ssid)#
exit
R3(config)
int dot11r0/0/0
R3(config-if)
?
arp Set arp type (arpa, probe, snap) or timeout or log options
bandwidth Set bandwidth informational parameter
cdp CDP interface subcommands
crypto Encryption/Decryption commands
delay Specify interface throughput delay
description Interface specific description
encryption Configure dot11 encryption parameters
exit Exit from interface configuration mode
fair-queue Enable Fair Queuing on an Interface
hold-queue Set hold queue depth
ip Interface Internet Protocol config commands
mac-address Manually set interface MAC address
mtu Set the interface Maximum Transmission Unit (MTU)
no Negate a command or set its defaults
priority-group Assign a priority group to an interface
service-policy Configure QoS Service Policy
shutdown Shutdown the selected interface
speed Set allowed radio bit rates
ssid Configure radio service set parameters
tx-ring-limit Configure PA level transmit ring limit
we have the option for ssid
R3(config-if)
ssid ADMIN2
%LINK-5-CHANGED: Interface Dot11Radio0/0/0, changed state to administratively down
%LINEPROTO-5-UPDOWN: Line protocol on Interface Dot11Radio0/0/0, changed state to down
%LINK-5-CHANGED: Interface Dot11Radio0/0/0, changed state to up
%LINEPROTO-5-UPDOWN: Line protocol on Interface Dot11Radio0/0/0, changed state to up
the router resets the interface..
-----------------------------------------------------------------------------------------------
R3(config-if)
do show run
[cut]
!
!
dot11 ssid ADMIN2
authentication open
guest-mode
!
!
[cut]
!
interface Dot11Radio0/0/0
description test router 2
ip address 172.16.10.1 255.255.255.0
speed 12.0 18.0 24.0 36.0 48.0 54.0 6.0 9.0 basic-1.0 basic-11.0 basic-2.0 basic-5.5
ssid ADMIN2
!
[cut]
the SSID is created and assigned to the interface
To summarize.
Wrong: create the dot11 interface, then create the SSID from CONFIG-IF mode, which puts you into CONFIG-IF-SSID (there is no such mode on this router) mode, then modify the ssid from there...
Correct: create the dot11 interface. Exit CONFIG-IF and go back to GLOBAL CONFIG. Create the SSID which puts you in CONFIG-SSID mode.
Configure the ssid. Then exit CONFIG-SSID. Back into CONFIG-IF, assign the SSID
We have one more task for R3- Configuring the DHCP pool for wireless clients.
R3(config)#
ip dhcp pool Admin creating the pool name as "Admin"
R3(dhcp-config)#
network 172.16.10.0 255.255.255.0
R3(dhcp-config)#
default-router 172.16.10.1 aka default-gateway for clients in the pool
R3(dhcp-config)#
ip name-server 172.16.10.4 dns server
*automatically exits dhcp-config prompt*
R3(config)#
ip dhcp excluded-address 172.16.10.1 172.16.10.10 excludes the range given
172.16.10.1 is the router interface- we need to specifically exclude it from the pool
this setup should allow the wireless client to pick up an IP after connecting to the open SSID.
However, I was having trouble at first-
even though I seemed to have the SSID set correctly, i was hitting a WEP password prompt
i didnt see any obvious issues with the wifi module im using on the laptop:
The Linksys-WPC300N module provides one 2.4GHz wireless interface suitable for connection to wireless networks.
The module supports protocols that use Ethernet for LAN access.
I ended up creating a new SSID, with the same settings as the original:
R3(config)#
dot11 ssid ADMIN2
R3(config-ssid)#
guest-mode
R3(config-ssid)#
authentication open
and then I assigned the ip address to ssid ADMIN2 instead of the orginal ADMIN ssid
R3(config)#
int dot110/0/0
R3(config-if)#
ip address 172.16.10.1 255.255.255.0
R3(config-if)#
description WLAN for mobile user
R3(config-if)#
no shut
R3(config-if)#
ssid ADMIN2
R3#
show run
Building configuration...
Current configuration : 1467 bytes
!
version 15.1
no service timestamps log datetime msec
no service timestamps debug datetime msec
no service password-encryption
!
hostname R3
!
!
!
enable secret 5 $1$mERr$V5ujdIM9bTB/I.ipB0gkJ0
!
!
ip dhcp excluded-address 172.16.10.1 172.16.10.10
!
ip dhcp pool Admin
network 172.16.10.0 255.255.255.0
default-router 172.16.10.1
!
dot11 ssid ADMIN
authentication open
guest-mode
!
dot11 ssid ADMIN2
authentication open
guest-mode
!
!
!
ip cef
no ipv6 cef
!
!
!
!
license udi pid CISCO2811/K9 sn FTX1017RE40-
!
!
!
!
!
!
!
!
!
no ip domain-lookup
ip name-server 172.16.10.4
!
!
spanning-tree mode pvst
!
!
!
!
!
!
interface FastEthernet0/0
description connection to corp router
ip address 10.1.5.2 255.255.255.0
duplex auto
speed auto
!
interface FastEthernet0/1
no ip address
duplex auto
speed auto
shutdown
!
interface Dot11Radio0/0/0
description WAN for mobile
ip address 172.16.10.1 255.255.255.0
speed 12.0 18.0 24.0 36.0 48.0 54.0 6.0 9.0 basic-1.0 basic-11.0 basic-2.0 basic-5.5
ssid ADMIN2
!
interface Dot11Radio0/0/1
no ip address
speed 18.0 36.0 48.0 54.0 9.0 basic-12.0 basic-24.0 basic-6.0
!
interface Vlan1
no ip address
shutdown
!
ip classless
!
ip flow-export version 9
!
!
!
banner motd ^C this is R3 $
this is R3 ^C
!
!
!
!
!
line con 0
exec-timeout 0 0
password console
logging synchronous
login
!
line aux 0
password aux
login
!
line vty 0 4
password telnet
login
line vty 5 15
password telnet
login
!
!
!
end
Recall the DHCP configuration on R3:
R3(config)#
ip dhcp pool Admin creating the pool name as "Admin"
R3(dhcp-config)#
network 172.16.10.0 255.255.255.0
R3(dhcp-config)#
default-router 172.16.10.1 aka default-gateway for clients in the pool
R3(dhcp-config)#
ip name-server 172.16.10.4 dns server
*automatically exits dhcp-config prompt*
R3(config)#
ip dhcp excluded-address 172.16.10.1 172.16.10.10 excludes the range given
172.16.10.1 is the router interface- we need to specifically exclude it from the pool
we can check the configuration:
R3#
show ip dhcp pool
Pool Admin :
Utilization mark (high/low) : 100 / 0
Subnet size (first/next) : 0 / 0
Total addresses : 254
Leased addresses : 1
Excluded addresses : 1
Pending event : none
1 subnet is currently in the pool
Current index IP address range Leased/Excluded/Total
172.16.10.1 172.16.10.1 - 172.16.10.254 1 / 1 / 254
R3#
show ip dhcp binding
IP address Client-ID/ Lease expiration Type
Hardware address
172.16.10.11 00D0.979A.733B -- Automatic
the show command is becoming more familiar
R3#
show ip?
access-lists List access lists
arp IP ARP table
bgp BGP information
cache IP fast-switching route cache
cef Cisco Express Forwarding
dhcp Show items in the DHCP database
eigrp IP-EIGRP show commands
inspect CBAC (Context Based Access Control) information
interface IP interface status and configuration
ips IPS (Intrusion Prevention System) information
nat IP NAT information
nbar Network-Based Application Recognition
ospf OSPF information
protocols IP routing protocol process parameters and statistics
rip IP RIP show commands
route IP routing table
ssh Information on SSH
we'll use show ip route soon on all the routers. For now, here is the output for R3:
R3#
show ip route
Codes: L - local, C - connected, S - static, R - RIP, M - mobile, B - BGP
D - EIGRP, EX - EIGRP external, O - OSPF, IA - OSPF inter area
N1 - OSPF NSSA external type 1, N2 - OSPF NSSA external type 2
E1 - OSPF external type 1, E2 - OSPF external type 2, E - EGP
i - IS-IS, L1 - IS-IS level-1, L2 - IS-IS level-2, ia - IS-IS inter area
* - candidate default, U - per-user static route, o - ODR
P - periodic downloaded static route
Gateway of last resort is not set
10.0.0.0/8 is variably subnetted, 2 subnets, 2 masks
C 10.1.5.0/24 is directly connected, FastEthernet0/0
L 10.1.5.2/32 is directly connected, FastEthernet0/0
172.16.0.0/16 is variably subnetted, 2 subnets, 2 masks
C 172.16.10.0/24 is directly connected, Dot11Radio0/0/0
L 172.16.10.1/32 is directly connected, Dot11Radio0/0/0
Before moving on to the routing configurations, here is a review of the topology
I have switched over to the DrawIO diagram app to lay out the topology.
The Packet Tracer diagram becomes
too crowded to see the labels; it's labeling system forces awkward positioning of the objects; the interface
label's cant be moved, so if objects are too close together their labels cover eachother.. not good.
DrawIO allows a cleaner layout with plenty of room to label interfaces and ip addresses.
As a compromise, I'll use both.
I have the packet tracer objects spread out just enough to see the interfaces
and the label for each router. From here I can jump into the CLI for each device.
The DrawIO diagram allows me to cleary see IP addresses
I want to also review all of the configurations we just performed:
PROBLEM
The book specifies that of the two serial conections between R1 and Corp, there should be a DCE on each end..
Both of my DCE's are on the same end.
First lets be sure we understand what DCE means:
networkengineering.stackexchange.com/
One side of the link (DCE), has to transmit the clock signal, which controls the data rate, and the other side (DTE) receives the clock signal.
That is good enough for now. Note that while the book does specify in the diagram that each side should have a DCE, it was not actually mentioned in the configs.
We did not set a DCE or clock rate when conifguring those interfaces.
To fix this in my Packet Tracer topology, I did some quick research:
While this post wasnt pertaining to Packet Tracer, it got me thinking about the cable itself.
I deleted both of my existing serial connections and looked at the options for creating a new cable.
I noticed one is a DCE and one is a DTE:
Fixed the issue
back to the configuration overview: 4 routers, abbreviated show run output
Corp
interface FastEthernet0/0
description connection to R3
ip address 10.1.5.1 255.255.255.0
duplex auto
speed auto
!
interface FastEthernet0/1
no ip address
duplex auto
speed auto
shutdown
!
interface Serial0/0/0
description 1st connection to R1
ip address 10.1.2.1 255.255.255.0
!
interface Serial0/0/1
description 2nd connection to R1
ip address 10.1.3.1 255.255.255.0
clock rate 2000000
!
interface Serial0/1/0
description connection to R2
ip address 10.1.4.1 255.255.255.0
!
interface Vlan1
description Switch Card to Core Network
ip address 10.1.1.1 255.255.255.0
!
interface FastEthernet1/0
description switch port connection to WWW Server
switchport mode access
switchport nonegotiate
!
interface FastEthernet1/1
description switch port connection to Email Server
switchport mode access
switchport nonegotiate
!
interface FastEthernet1/2
description switch port connection to DNS Server
switchport mode access
switchport nonegotiate
!
R1
interface FastEthernet0/0
description connection to Finance
ip address 192.168.10.1 255.255.255.0
duplex auto
speed auto
!
interface FastEthernet0/1
description connection to Marketing
ip address 192.168.20.1 255.255.255.0
duplex auto
speed auto
!
interface Serial0/0/0
description 1st connection to Corp router
ip address 10.1.2.2 255.255.255.0
clock rate 2000000
!
interface Serial0/0/1
description 2nd connecction to Corp router
ip address 10.1.3.2 255.255.255.0
!
R2
interface FastEthernet0/0
description Connection to Sales PC
ip address 192.168.30.1 255.255.255.0
duplex auto
speed auto
!
interface FastEthernet0/1
description Connection to HR PC
ip address 192.168.40.1 255.255.255.0
duplex auto
speed auto
!
interface Serial0/0/0
description Connection to Corp Router
ip address 10.1.4.2 255.255.255.0
clock rate 2000000
!
interface Serial0/0/1
no ip address
clock rate 2000000
shutdown
!
R3
interface FastEthernet0/0
description connection to corp router
ip address 10.1.5.2 255.255.255.0
duplex auto
speed auto
!
interface FastEthernet0/1
no ip address
duplex auto
speed auto
shutdown
!
interface Dot11Radio0/0/0
description WAN for mobile
ip address 172.16.10.1 255.255.255.0
speed 12.0 18.0 24.0 36.0 48.0 54.0 6.0 9.0 basic-1.0 basic-11.0 basic-2.0 basic-5.5
ssid ADMIN2
and here is the output of show ip route for each router
Codes: C - connected, S - static, I - IGRP, R - RIP, M - mobile, B - BGP
D - EIGRP, EX - EIGRP external, O - OSPF, IA - OSPF inter area
N1 - OSPF NSSA external type 1, N2 - OSPF NSSA external type 2
E1 - OSPF external type 1, E2 - OSPF external type 2, E - EGP
i - IS-IS, L1 - IS-IS level-1, L2 - IS-IS level-2, ia - IS-IS inter area
* - candidate default, U - per-user static route, o - ODR
P - periodic downloaded static route
Gateway of last resort is not set
Corp
10.0.0.0/24 is subnetted, 2 subnets
C 10.1.2.0 is directly connected, Serial0/0/0
C 10.1.3.0 is directly connected, Serial0/0/1
C 192.168.10.0/24 is directly connected, FastEthernet0/0
C 192.168.20.0/24 is directly connected, FastEthernet0/1
R1
10.0.0.0/24 is subnetted, 2 subnets
C 10.1.2.0 is directly connected, Serial0/0/0
C 10.1.3.0 is directly connected, Serial0/0/1
C 192.168.10.0/24 is directly connected, FastEthernet0/0
C 192.168.20.0/24 is directly connected, FastEthernet0/1
R2
10.0.0.0/24 is subnetted, 1 subnets
C 10.1.4.0 is directly connected, Serial0/0/0
C 192.168.30.0/24 is directly connected, FastEthernet0/0
C 192.168.40.0/24 is directly connected, FastEthernet0/1
R3
10.0.0.0/8 is variably subnetted, 2 subnets, 2 masks
C 10.1.5.0/24 is directly connected, FastEthernet0/0
L 10.1.5.2/32 is directly connected, FastEthernet0/0
172.16.0.0/16 is variably subnetted, 2 subnets, 2 masks
C 172.16.10.0/24 is directly connected, Dot11Radio0/0/0
L 172.16.10.1/32 is directly connected, Dot11Radio0/0/0
Note that this is before we have configured any 'routing'. We are seeing configured, directly connected networks.
The output for R3 is particularly interesting
What does 'variably' subnetted mean, and what is the "L" next to these routes. And why do they have a mask of 32?
R3
10.0.0.0/8 is variably subnetted, 2 subnets, 2 masks
C 10.1.5.0/24 is directly connected, FastEthernet0/0
L 10.1.5.2/32 is directly connected, FastEthernet0/0
172.16.0.0/16 is variably subnetted, 2 subnets, 2 masks
C 172.16.10.0/24 is directly connected, Dot11Radio0/0/0
L 172.16.10.1/32 is directly connected, Dot11Radio0/0/0
Cisco forums
That makes sense, but my question is why did the other routing tables not behave the same way? R3 is the only one that shows "L" routes.
The book tells us we're using two different model routers, and indeed they are running different IOS versions:
NOTE that at the time the book was published IOS 15 was not released yet, so the book assumes all routers are running 12.4
But that still doesnt explain why Corp and R3 are behaving differently..
Corp
10.0.0.0/24 is subnetted, 2 subnets
C 10.1.2.0 is directly connected, Serial0/0/0
C 10.1.3.0 is directly connected, Serial0/0/1
C 192.168.10.0/24 is directly connected, FastEthernet0/0
C 192.168.20.0/24 is directly connected, FastEthernet0/1
R1
10.0.0.0/24 is subnetted, 2 subnets
C 10.1.2.0 is directly connected, Serial0/0/0
C 10.1.3.0 is directly connected, Serial0/0/1
C 192.168.10.0/24 is directly connected, FastEthernet0/0
C 192.168.20.0/24 is directly connected, FastEthernet0/1
R2
10.0.0.0/24 is subnetted, 1 subnets
C 10.1.4.0 is directly connected, Serial0/0/0
C 192.168.30.0/24 is directly connected, FastEthernet0/0
C 192.168.40.0/24 is directly connected, FastEthernet0/1
R3
10.0.0.0/8 is variably subnetted, 2 subnets, 2 masks
C 10.1.5.0/24 is directly connected, FastEthernet0/0
L 10.1.5.2/32 is directly connected, FastEthernet0/0
172.16.0.0/16 is variably subnetted, 2 subnets, 2 masks
C 172.16.10.0/24 is directly connected, Dot11Radio0/0/0
L 172.16.10.1/32 is directly connected, Dot11Radio0/0/0
how are Corp and R3 different?
The answer is, they are not...
I have accidentally displayed the R1 output to the Corp windows. Error in translating data from the IOS to this webpage..
here's the corrected output.
Corp
10.0.0.0/8 is variably subnetted, 10 subnets, 2 masks
C 10.1.1.0/24 is directly connected, Vlan1
L 10.1.1.1/32 is directly connected, Vlan1
C 10.1.2.0/24 is directly connected, Serial0/0/0
L 10.1.2.1/32 is directly connected, Serial0/0/0
C 10.1.3.0/24 is directly connected, Serial0/0/1
L 10.1.3.1/32 is directly connected, Serial0/0/1
C 10.1.4.0/24 is directly connected, Serial0/1/0
L 10.1.4.1/32 is directly connected, Serial0/1/0
C 10.1.5.0/24 is directly connected, FastEthernet0/0
L 10.1.5.1/32 is directly connected, FastEthernet0/0
R1
10.0.0.0/24 is subnetted, 2 subnets
C 10.1.2.0 is directly connected, Serial0/0/0
C 10.1.3.0 is directly connected, Serial0/0/1
C 192.168.10.0/24 is directly connected, FastEthernet0/0
C 192.168.20.0/24 is directly connected, FastEthernet0/1
R2
10.0.0.0/24 is subnetted, 1 subnets
C 10.1.4.0 is directly connected, Serial0/0/0
C 192.168.30.0/24 is directly connected, FastEthernet0/0
C 192.168.40.0/24 is directly connected, FastEthernet0/1
R3
10.0.0.0/8 is variably subnetted, 2 subnets, 2 masks
C 10.1.5.0/24 is directly connected, FastEthernet0/0
L 10.1.5.2/32 is directly connected, FastEthernet0/0
172.16.0.0/16 is variably subnetted, 2 subnets, 2 masks
C 172.16.10.0/24 is directly connected, Dot11Radio0/0/0
L 172.16.10.1/32 is directly connected, Dot11Radio0/0/0
We do indeed see consistent behavior differences between IOS versions 12.4 and 15.1
recap Corp and R3 outputs:
update topology with Router versions
That covers the first half of Chapter 8. Now we are ready to configure IP routing on our network.
There are three ways: Static, Default, Dynamic
To set up static routes, we simply need to program the routes using the ip route command
Syntax
ip route
[
destination network
]
[
mask
]
[
next hop
]
[
exitinterface
]
[
administrative distance
]
[
permanent
]
destination network and mask
the network data we're adding to the routing table
next-hop address
the address of the next-hop router that will receive the packet and forward to the remote network.
This is the IP address of a router interface that is directly connected.
It must be pingable.
exit interface
can be used instead of next hop address
administrative distance
by default, static routes have an admin distance of 1 if you use a next hop, or 0 if you use exit interface.
You can change the value by adding an administrative weight at the end of the command. More on this later with dynamic routing.
permanent
if the interface is shut down or the router cant communicate to the next hp router, the route will automatically be discarded from the table by default.
The 'permanent' option keeps the entry in the routing table indefenitely.
-----------------------------------------------------------------------------------------------------
Corp has automatically picked up 5 routes that are directly connected:
10.1.1.0 to corp switch card
10.1.2.0 to R1
10.1.3.0 to R1
10.1.4.0 to R2
10.1.5.0 to R3
We need to program 5 more routes:
192.168.10.0 traverse R1
192.168.20.0 traverse R1
192.168.30.0 traverse R1
192.168.40.0 traverse R2
172.16.10.0 traverse R3
-----------------------------------------------------------------------------------------------------
R1 has automatically picked up 4 routes that are directly connected:
10.1.2.0
10.1.3.0
192.168.10.0
192.168.20.0
We need to program 6 more routes:
10.1.1.0
10.1.4.0
10.1.5.0
192.168.30.0
192.168.40.0
172.16.10.0
-----------------------------------------------------------------------------------------------------
R2 has automatically picked up 3 routes that are directly connected:
10.1.4.0
192.168.30.0
192.168.40.0
We need to program 7 more routes:
10.1.1.0
10.1.2.0
10.1.3.0
10.1.5.0
192.168.10.0
192.168.20.0
172.16.10.0
-----------------------------------------------------------------------------------------------------
R3 has automatically picked up 2 routes that are directly connected:
10.1.5.0
172.16.10.0
We need to program 8 more routes:
10.1.1.0
10.1.2.0
10.1.3.0
10.1.4.0
192.168.10.0
192.168.20.0
192.168.30.0
192.168.40.0
Notice the pattern- each router ends up with 10 routes
There are 10 routes total in this topology. AKA ten broadcast domains
Programming the routes
Corp
Corp(config)#
ip route 192.168.10.0 255.255.255.0 10.1.2.2 150
Corp(config)#
ip route 192.168.20.0 255.255.255.0 10.1.3.2 150
Corp(config)#
ip route 192.168.30.0 255.255.255.0 10.1.4.2 150
Corp(config)#
ip route 192.168.40.0 255.255.255.0 10.1.4.2 150
Corp(config)#
ip route 172.16.10.0 255.255.255.0 10.1.5.2 150
Corp(config)#
do show ip route
In the first line, the router is saying that a
classful A network is being subnetted
There are 5 routes directly connected
We see two lines per route (one for the network and one
for the interface(/32)-
10.0.0.0/8 is variably subnetted, 10 subnets, 2 masks
C 10.1.1.0/24 is directly connected, Vlan1
L 10.1.1.1/32 is directly connected, Vlan1
C 10.1.2.0/24 is directly connected, Serial0/0/0
L 10.1.2.1/32 is directly connected, Serial0/0/0
C 10.1.3.0/24 is directly connected, Serial0/0/1
L 10.1.3.1/32 is directly connected, Serial0/0/1
C 10.1.4.0/24 is directly connected, Serial0/1/0
L 10.1.4.1/32 is directly connected, Serial0/1/0
C 10.1.5.0/24 is directly connected, FastEthernet0/0
L 10.1.5.1/32 is directly connected, FastEthernet0/0
and 5 routes that require traversal of a router to reach
172.16.0.0/24 is subnetted, 1 subnets
S 172.16.10.0/24 [150/0] via 10.1.5.2
S 192.168.10.0/24 [150/0] via 10.1.2.2
S 192.168.20.0/24 [150/0] via 10.1.3.2
S 192.168.30.0/24 [150/0] via 10.1.4.2
S 192.168.40.0/24 [150/0] via 10.1.4.2
R1
R1(config)#
ip route 10.1.1.0 255.255.255.0 10.1.2.1 150
R1(config)#
ip route 10.1.4.0 255.255.255.0 10.1.3.1 150
R1(config)#
ip route 10.1.5.0 255.255.255.0 10.1.2.1 150
R1(config)#
ip route 192.168.30.0 255.255.255.0 10.1.3.1 150
R1(config)#
ip route 192.168.40.0 255.255.255.0 10.1.2.1 150
R1(config)#
ip route 172.16.10.0 255.255.255.0 10.1.3.1 150
the only way to get across the corp router is to go into it via 10.1.2.1 or 10.1.3.1
R1(config)#
do show ip route
10.0.0.0/24 is subnetted, 5 subnets
S 10.1.1.0 [150/0] via 10.1.2.1
C 10.1.2.0 is directly connected, Serial0/0/0
C 10.1.3.0 is directly connected, Serial0/0/1
S 10.1.4.0 [150/0] via 10.1.3.1
S 10.1.5.0 [150/0] via 10.1.2.1
172.16.0.0/24 is subnetted, 1 subnets
S 172.16.10.0 [150/0] via 10.1.3.1
C 192.168.10.0/24 is directly connected, FastEthernet0/0
C 192.168.20.0/24 is directly connected, FastEthernet0/1
S 192.168.30.0/24 [150/0] via 10.1.3.1
S 192.168.40.0/24 [150/0] via 10.1.2.1
R2
R2(config)#
iproute 10.1.1.0 255.255.255.0 10.1.4.1 150
R2(config)#
iproute 10.1.2.0 255.255.255.0 10.1.4.1 150
R2(config)#
iproute 10.1.3.0 255.255.255.0 10.1.4.1 150
R2(config)#
iproute 10.1.5.0 255.255.255.0 10.1.4.1 150
R2(config)#
iproute 192.168.10.0 255.255.255.0 10.1.4.1 150
R2(config)#
iproute 192.168.20.0 255.255.255.0 10.1.4.1 150
the only way to get across Corp is to go into it via 10.1.4.1
R2(config)#
do show ip route
10.0.0.0/24 is subnetted, 5 subnets
S 10.1.1.0 [150/0] via 10.1.4.1
S 10.1.2.0 [150/0] via 10.1.4.1
S 10.1.3.0 [150/0] via 10.1.4.1
C 10.1.4.0 is directly connected, Serial0/0/0
S 10.1.5.0 [150/0] via 10.1.4.1
172.16.0.0/24 is subnetted, 1 subnets
S 172.16.10.0 [150/0] via 10.1.4.1
S 192.168.10.0/24 [150/0] via 10.1.4.1
S 192.168.20.0/24 [150/0] via 10.1.4.1
C 192.168.30.0/24 is directly connected, FastEthernet0/0
C 192.168.40.0/24 is directly connected, FastEthernet0/1
R3
R3(config)#
ip route 10.1.1.0 255.255.255.0 fastethernet 0/0 150
R3(config)#
ip route 10.1.2.0 255.255.255.0 fastethernet 0/0 150
R3(config)#
ip route 10.1.3.0 255.255.255.0 fastethernet 0/0 150
R3(config)#
ip route 10.1.4.0 255.255.255.0 fastethernet 0/0 150
R3(config)#
ip route 192.168.10.0 255.255.255.0 fastethernet 0/0 150
R3(config)#
ip route 192.168.20.0 255.255.255.0 fastethernet 0/0 150
R3(config)#
ip route 192.168.30.0 255.255.255.0 fastethernet 0/0 150
R3(config)#
ip route 192.168.40.0 255.255.255.0 fastethernet 0/0 150
the only way to get across Corp is to EXIT R3 via F0/0
R3(config)#
do show ip route
10.0.0.0/8 is variably subnetted, 6 subnets, 2 masks
S 10.1.1.0/24 is directly connected, FastEthernet0/0
S 10.1.2.0/24 is directly connected, FastEthernet0/0
S 10.1.3.0/24 is directly connected, FastEthernet0/0
S 10.1.4.0/24 is directly connected, FastEthernet0/0
C 10.1.5.0/24 is directly connected, FastEthernet0/0
L 10.1.5.2/32 is directly connected, FastEthernet0/0
172.16.0.0/16 is variably subnetted, 2 subnets, 2 masks
C 172.16.10.0/24 is directly connected, Dot11Radio0/0/0
L 172.16.10.1/32 is directly connected, Dot11Radio0/0/0
S 192.168.10.0/24 is directly connected, FastEthernet0/0
S 192.168.20.0/24 is directly connected, FastEthernet0/0
S 192.168.30.0/24 is directly connected, FastEthernet0/0
S 192.168.40.0/24 is directly connected, FastEthernet0/0
before verifying connectivity across the network, we need to make sure all of our hosts are set. The book is giving us the IP addresses for the servers:
Server Gateway 10.1.1.1
ServerWeb 10.1.1.2
ServerEmail 10.1.1.3
ServerDNS 10.1.1.4
Now we can do some testing across the network:
R3#
ping 10.1.2.2
traverse Corp to R1
R3#
ping 10.1.1.1
traverse Corp to a Corp interface we arent directly connected to
R3#
ping 10.1.1.2
traverse Corp to Web server
R3#
ping 10.1.1.3
traverse Corp to Email server
R3#
ping 10.1.1.4
traverse Corp to DNS server
MobileUser
ping 192.168.10.2
traverse R3, Corp, R1 to Finance client
MobileUser
tracert 192.168.10.2
traverse R3, Corp, R1 to Finance client
Tracing route to 192.168.10.2 over a maximum of 30 hops:
1 19 ms 5 ms 20 ms 172.16.10.1
2 20 ms 6 ms 11 ms 10.1.5.1
3 11 ms 15 ms 10 ms 10.1.3.2
4 9 ms 13 ms 22 ms 192.168.10.2
Trace complete.
notice how the trace doesnt count an egress as a hop, only an ingress
ALSO NOTE that tracert is a Windows command.
the IOS equivalent is traceroute
notice how the output differs from the Windows command
R3
traceroute 192.168.10.2
Type escape sequence to abort.
Tracing the route to 192.168.10.2
1 10.1.5.1 0 msec 0 msec 0 msec
2 10.1.2.2 6 msec 0 msec 5 msec
3 192.168.10.2 1 msec 4 msec 3 msec
Default Routing
we could have done this on R3
R3(config)#
ip route 0.0.0.0 0.0.0.0 10.1.5.1
as an alternative to this configuration on R3
R3(config)#
ip route 10.1.1.0 255.255.255.0 fastethernet 0/0 150
R3(config)#
ip route 10.1.2.0 255.255.255.0 fastethernet 0/0 150
R3(config)#
ip route 10.1.3.0 255.255.255.0 fastethernet 0/0 150
R3(config)#
ip route 10.1.4.0 255.255.255.0 fastethernet 0/0 150
R3(config)#
ip route 192.168.10.0 255.255.255.0 fastethernet 0/0 150
R3(config)#
ip route 192.168.20.0 255.255.255.0 fastethernet 0/0 150
R3(config)#
ip route 192.168.30.0 255.255.255.0 fastethernet 0/0 150
R3(config)#
ip route 192.168.40.0 255.255.255.0 fastethernet 0/0 150
the only way to get across Corp is to EXIT R3 via F0/0
This is called default routing. It should only be used on 'stub routers'- those with only one exit path out of the network.
if you try to put a default route on a non-stub router, you could create loops, since there will be more than one path to other routers...
Think of a default route as a static route that uses a wildcard address and mask. The wildcard is 0.0.0.0
to further analyze this comparison, I'm going to remove the routes from R3...
R3(config)#
no ip route 10.1.1.0 255.255.255.0 fastethernet0/0 150
R3(config)#
no ip route 10.1.2.0 255.255.255.0 fastethernet0/0 150
R3(config)#
no ip route 10.1.3.0 255.255.255.0 fastethernet0/0 150
R3(config)#
no ip route 10.1.4.0 255.255.255.0 fastethernet0/0 150
R3(config)#
no ip route 192.168.10.0 255.255.255.0 fastethernet0/0 150
R3(config)#
no ip route 192.168.20.0 255.255.255.0 fastethernet0/0 150
R3(config)#
no ip route 192.168.30.0 255.255.255.0 fastethernet0/0 150
R3(config)#
no ip route 192.168.40.0 255.255.255.0 fastethernet0/0 150
and then set the default route instead.
R3#
ip route 0.0.0.0 0.0.0.0 10.1.5.1 --- ingress at next hop
OR
R3#
ip route 0.0.0.0 0.0.0.0 Fa0/0 --- egress interface
Then compare the output of show ip route
static routes set
R3#
show ip route
Gateway of last resort is not set
10.0.0.0/8 is variably subnetted, 6 subnets, 2 masks
S 10.1.1.0/24 is directly connected, FastEthernet0/0
S 10.1.2.0/24 is directly connected, FastEthernet0/0
S 10.1.3.0/24 is directly connected, FastEthernet0/0
S 10.1.4.0/24 is directly connected, FastEthernet0/0
C 10.1.5.0/24 is directly connected, FastEthernet0/0
L 10.1.5.2/32 is directly connected, FastEthernet0/0
172.16.0.0/16 is variably subnetted, 2 subnets, 2 masks
C 172.16.10.0/24 is directly connected, Dot11Radio0/0/0
L 172.16.10.1/32 is directly connected, Dot11Radio0/0/0
S 192.168.10.0/24 is directly connected, FastEthernet0/0
S 192.168.20.0/24 is directly connected, FastEthernet0/0
S 192.168.30.0/24 is directly connected, FastEthernet0/0
S 192.168.40.0/24 is directly connected, FastEthernet0/0
default route set
R3#
show ip route
Gateway of last resort is 10.1.5.1 to network 0.0.0.0
10.0.0.0/8 is variably subnetted, 2 subnets, 2 masks
C 10.1.5.0/24 is directly connected, FastEthernet0/0
L 10.1.5.2/32 is directly connected, FastEthernet0/0
172.16.0.0/16 is variably subnetted, 2 subnets, 2 masks
C 172.16.10.0/24 is directly connected, Dot11Radio0/0/0
L 172.16.10.1/32 is directly connected, Dot11Radio0/0/0
S* 0.0.0.0/0 [1/0] via 10.1.5.1
two directly connected networks- 10.1.5.0 and 172.16.10.0
anything not included in those networks goes to ingress of attached neighbor Corp 10.1.5.1
in this toplogy, that includes:
192.168.10.0
192.168.20.0
192.168.30.0
192.168.40.0
and
10.1.1.0
10.1.2.0
10.1.3.0
10.1.4.0
RIP Routing Information Protocol
R1(config)#
router ?
bgp Border Gateway Protocol (BGP)
eigrp Enhanced Interior Gateway Routing Protocol (EIGRP)
ospf Open Shortest Path First (OSPF)
rip Routing Information Protocol (RIP)
set RIP on Corp
Corp(config)#
router rip
Corp(config-router)#
network 10.0.0.0
set RIP on R1
R1(config)#
router rip
R1(config-router)#
network 10.0.0.0
R1 routing table
R1(config)#
do show ip route
10.0.0.0/24 is subnetted, 5 subnets
R 10.1.1.0 [120/1] via 10.1.2.1, 00:00:21, Serial0/0/0
[120/1] via 10.1.3.1, 00:00:21, Serial0/0/1
C 10.1.2.0 is directly connected, Serial0/0/0
C 10.1.3.0 is directly connected, Serial0/0/1
R 10.1.4.0 [120/1] via 10.1.2.1, 00:00:21, Serial0/0/0
[120/1] via 10.1.3.1, 00:00:21, Serial0/0/1
R 10.1.5.0 [120/1] via 10.1.2.1, 00:00:21, Serial0/0/0
[120/1] via 10.1.3.1, 00:00:21, Serial0/0/1
172.16.0.0/24 is subnetted, 1 subnets
S 172.16.10.0 [150/0] via 10.1.3.1
C 192.168.10.0/24 is directly connected, FastEthernet0/0
C 192.168.20.0/24 is directly connected, FastEthernet0/1
S 192.168.30.0/24 [150/0] via 10.1.3.1
S 192.168.40.0/24 [150/0] via 10.1.2.1
here's R1 before RIP, with only static routes set:
R1(config)#
do show ip route
10.0.0.0/24 is subnetted, 5 subnets
S 10.1.1.0 [150/0] via 10.1.2.1
C 10.1.2.0 is directly connected, Serial0/0/0
C 10.1.3.0 is directly connected, Serial0/0/1
S 10.1.4.0 [150/0] via 10.1.3.1
S 10.1.5.0 [150/0] via 10.1.2.1
172.16.0.0/24 is subnetted, 1 subnets
S 172.16.10.0 [150/0] via 10.1.3.1
C 192.168.10.0/24 is directly connected, FastEthernet0/0
C 192.168.20.0/24 is directly connected, FastEthernet0/1
S 192.168.30.0/24 [150/0] via 10.1.3.1
S 192.168.40.0/24 [150/0] via 10.1.2.1
These RIP routes are being advertised as available *to other RIP routers*.
CORP is advertisting THREE routes via RIP to R1 right now
10.1.1.0
10.1.4.0
10.1.5.0
access to those networks can be achieved by R1 by going THROUGH CORP via ingress .2.1 or .3.1
The advantage..... is that we didnt statically program these routes
we engaged RIP, on BOTH routers- R1 and Corp, and handed them BOTH the network "10.0.0.0"
So, why did RIP choose to display these particular routes
Keep in mind that the output above is from R1 only... In the context of the R1 ROUTER ONLY,
there are three relevant routes within the "10.0.0.0" parameter we specified. The three routes involve Corp.
Corp is sending RIP data about these routes to Corp.
Lets look closer at how this is happening:
here's our starting point before any RIP is set
here's our routing tables after i set RIP with 10.0.0.0 on both..
FIRST i set it on Corp, then R1.(per the book's instructions) As a result we are seeing RIP routes in R1 only....
then I went back to a fresh packet tracer file with no RIP set. And I set RIP in the opposite order;
FIRST i set it on R1, then Corp. And again, we are seeing RIP routes in R1 only....
I wanted to prove that it didnt matter which order we enabled RIP on the two routers. What matters here is that
we enable RIP on both of them with the criteria of 10.0.0.0
Recall the topology:
if Corp and R1 are set for RIP and given the criteria 10.0.0.0, meaning that we are trying to reach networks
within that range, then it follows that Corp will advertise 1.1.0, 1.4.0, and 1.5.0 to R1, because Corp stands between those networks
and R1
"Hi R1, I'm Corp I have three networks that fall inside 10.0.0.0, and you can reach them through me via .2.1 or .3.1"
It also follows that Corp's routing table shows no RIP routes- because R1 isnt advertising any. R1 doesnt have any networks
in the 10.0.0.0 range that Corp could reach
To further clarify this, we'll proceed with the book's instructions. We'll now set more RIP routes on R1
R1(config)#
router rip
R1(config-router)#
network 192.168.10.0
R1(config-router)#
network 192.168.20.0
Corp routing table before RIP set on R1:
Corp#
show ip route
10.0.0.0/8 is variably subnetted, 10 subnets, 2 masks
C 10.1.1.0/24 is directly connected, Vlan1
L 10.1.1.1/32 is directly connected, Vlan1
C 10.1.2.0/24 is directly connected, Serial0/0/0
L 10.1.2.1/32 is directly connected, Serial0/0/0
C 10.1.3.0/24 is directly connected, Serial0/0/1
L 10.1.3.1/32 is directly connected, Serial0/0/1
C 10.1.4.0/24 is directly connected, Serial0/1/0
L 10.1.4.1/32 is directly connected, Serial0/1/0
C 10.1.5.0/24 is directly connected, FastEthernet0/0
L 10.1.5.1/32 is directly connected, FastEthernet0/0
172.16.0.0/24 is subnetted, 1 subnets
S 172.16.10.0/24 [150/0] via 10.1.5.2
S 192.168.10.0/24 [150/0] via 10.1.2.2
S 192.168.20.0/24 [150/0] via 10.1.3.2
S 192.168.30.0/24 [150/0] via 10.1.4.2
S 192.168.40.0/24 [150/0] via 10.1.4.2
Corp routing table after RIP set on R1:
Gateway of last resort is not set
10.0.0.0/8 is variably subnetted, 10 subnets, 2 masks
C 10.1.1.0/24 is directly connected, Vlan1
L 10.1.1.1/32 is directly connected, Vlan1
C 10.1.2.0/24 is directly connected, Serial0/0/0
L 10.1.2.1/32 is directly connected, Serial0/0/0
C 10.1.3.0/24 is directly connected, Serial0/0/1
L 10.1.3.1/32 is directly connected, Serial0/0/1
C 10.1.4.0/24 is directly connected, Serial0/1/0
L 10.1.4.1/32 is directly connected, Serial0/1/0
C 10.1.5.0/24 is directly connected, FastEthernet0/0
L 10.1.5.1/32 is directly connected, FastEthernet0/0
nothing changed so far
172.16.0.0/24 is subnetted, 1 subnets
S 172.16.10.0/24 [150/0] via 10.1.5.2
no change
R 192.168.10.0/24 [120/1] via 10.1.2.2, 00:00:08, Serial0/0/0
[120/1] via 10.1.3.2, 00:00:08, Serial0/0/1
RIP overrides static- 2 paths available now
R 192.168.20.0/24 [120/1] via 10.1.2.2, 00:00:08, Serial0/0/0
[120/1] via 10.1.3.2, 00:00:08, Serial0/0/1
RIP overrides static- 2 paths available now
S 192.168.30.0/24 [150/0] via 10.1.4.2
no change
S 192.168.40.0/24 [150/0] via 10.1.4.2
no change
"Hi Corp- I'm R1 and I have zero networks
that fall inside 10.0.0.0, however I do have some networks that fall within
192.168.20.0 and 192.168.10.0
and you can reach them through me(R1) if you ingress at .1.2.2 or .1.3.2"
ok, we have the concept down. Time to proceed and set up RIP on R2............
R2(config)#
router rip
R2(config-router)#
network 10.0.0.0
R2(config-router)#
network 192.168.30.0
R2(config-router)#
network 192.168.40.0
R2 before RIP enabled
R2#
show ip route
10.0.0.0/24 is subnetted, 5 subnets
S 10.1.1.0 [150/0] via 10.1.4.1
S 10.1.2.0 [150/0] via 10.1.4.1
S 10.1.3.0 [150/0] via 10.1.4.1
C 10.1.4.0 is directly connected, Serial0/0/0
S 10.1.5.0 [150/0] via 10.1.4.1
172.16.0.0/24 is subnetted, 1 subnets
S 172.16.10.0 [150/0] via 10.1.4.1
S 192.168.10.0/24 [150/0] via 10.1.4.1
S 192.168.20.0/24 [150/0] via 10.1.4.1
C 192.168.30.0/24 is directly connected, FastEthernet0/0
C 192.168.40.0/24 is directly connected, FastEthernet0/1
R2 after RIP added
R2#
show ip route
10.0.0.0/24 is subnetted, 5 subnets
R 10.1.1.0 [120/1] via 10.1.4.1, 00:00:24, Serial0/0/0
from corp
R 10.1.2.0 [120/1] via 10.1.4.1, 00:00:24, Serial0/0/0
from corp
R 10.1.3.0 [120/1] via 10.1.4.1, 00:00:24, Serial0/0/0
from corp
C 10.1.4.0 is directly connected, Serial0/0/0
R 10.1.5.0 [120/1] via 10.1.4.1, 00:00:24, Serial0/0/0
from corp
172.16.0.0/24 is subnetted, 1 subnets
S 172.16.10.0 [150/0] via 10.1.4.1
R 192.168.10.0/24 [120/2] via 10.1.4.1, 00:00:24, Serial0/0/0
from R1 via corp
R 192.168.20.0/24 [120/2] via 10.1.4.1, 00:00:24, Serial0/0/0
from R1 via corp
C 192.168.30.0/24 is directly connected, FastEthernet0/0
C 192.168.40.0/24 is directly connected, FastEthernet0/1
now lets compare the Corp and R1 routing tables- before RIP was set on R2 and after
Corp before R2 RIP
Corp#
show ip route
10.0.0.0/8 is variably subnetted, 10 subnets, 2 masks
C 10.1.1.0/24 is directly connected, Vlan1
L 10.1.1.1/32 is directly connected, Vlan1
C 10.1.2.0/24 is directly connected, Serial0/0/0
L 10.1.2.1/32 is directly connected, Serial0/0/0
C 10.1.3.0/24 is directly connected, Serial0/0/1
L 10.1.3.1/32 is directly connected, Serial0/0/1
C 10.1.4.0/24 is directly connected, Serial0/1/0
L 10.1.4.1/32 is directly connected, Serial0/1/0
C 10.1.5.0/24 is directly connected, FastEthernet0/0
L 10.1.5.1/32 is directly connected, FastEthernet0/0
172.16.0.0/24 is subnetted, 1 subnets
S 172.16.10.0/24 [150/0] via 10.1.5.2
R 192.168.10.0/24 [120/1] via 10.1.2.2, 00:00:02, Serial0/0/0
[120/1] via 10.1.3.2, 00:00:02, Serial0/0/1
R 192.168.20.0/24 [120/1] via 10.1.2.2, 00:00:02, Serial0/0/0
[120/1] via 10.1.3.2, 00:00:02, Serial0/0/1
from R1
S 192.168.30.0/24 [150/0] via 10.1.4.2
S 192.168.40.0/24 [150/0] via 10.1.4.2
Corp after R2 RIP
Corp#
show ip route
10.0.0.0/8 is variably subnetted, 10 subnets, 2 masks
C 10.1.1.0/24 is directly connected, Vlan1
L 10.1.1.1/32 is directly connected, Vlan1
C 10.1.2.0/24 is directly connected, Serial0/0/0
L 10.1.2.1/32 is directly connected, Serial0/0/0
C 10.1.3.0/24 is directly connected, Serial0/0/1
L 10.1.3.1/32 is directly connected, Serial0/0/1
C 10.1.4.0/24 is directly connected, Serial0/1/0
L 10.1.4.1/32 is directly connected, Serial0/1/0
C 10.1.5.0/24 is directly connected, FastEthernet0/0
L 10.1.5.1/32 is directly connected, FastEthernet0/0
172.16.0.0/24 is subnetted, 1 subnets
S 172.16.10.0/24 [150/0] via 10.1.5.2
R 192.168.10.0/24 [120/1] via 10.1.2.2, 00:00:19, Serial0/0/0
[120/1] via 10.1.3.2, 00:00:19, Serial0/0/1
R 192.168.20.0/24 [120/1] via 10.1.2.2, 00:00:19, Serial0/0/0
[120/1] via 10.1.3.2, 00:00:19, Serial0/0/1
from R1
R 192.168.30.0/24 [120/1] via 10.1.4.2, 00:00:15, Serial0/1/0
R 192.168.40.0/24 [120/1] via 10.1.4.2, 00:00:15, Serial0/1/0
from R2
RIP on R2 is advertising .30.0 and .40.0 to Corp
R1 before R2 RIP
R1#
show ip route
10.0.0.0/24 is subnetted, 5 subnets
R 10.1.1.0 [120/1] via 10.1.2.1, 00:00:05, Serial0/0/0
[120/1] via 10.1.3.1, 00:00:05, Serial0/0/1
from Corp
C 10.1.2.0 is directly connected, Serial0/0/0
C 10.1.3.0 is directly connected, Serial0/0/1
R 10.1.4.0 [120/1] via 10.1.2.1, 00:00:05, Serial0/0/0
[120/1] via 10.1.3.1, 00:00:05, Serial0/0/1
R 10.1.5.0 [120/1] via 10.1.2.1, 00:00:05, Serial0/0/0
[120/1] via 10.1.3.1, 00:00:05, Serial0/0/1
from Corp
172.16.0.0/24 is subnetted, 1 subnets
S 172.16.10.0 [150/0] via 10.1.3.1
C 192.168.10.0/24 is directly connected, FastEthernet0/0
C 192.168.20.0/24 is directly connected, FastEthernet0/1
S 192.168.30.0/24 [150/0] via 10.1.3.1
S 192.168.40.0/24 [150/0] via 10.1.2.1
R1 after R2 RIP
R1#
show ip route
10.0.0.0/24 is subnetted, 5 subnets
R 10.1.1.0 [120/1] via 10.1.2.1, 00:00:06, Serial0/0/0
[120/1] via 10.1.3.1, 00:00:06, Serial0/0/1
from Corp
C 10.1.2.0 is directly connected, Serial0/0/0
C 10.1.3.0 is directly connected, Serial0/0/1
R 10.1.4.0 [120/1] via 10.1.2.1, 00:00:06, Serial0/0/0
[120/1] via 10.1.3.1, 00:00:06, Serial0/0/1
R 10.1.5.0 [120/1] via 10.1.2.1, 00:00:06, Serial0/0/0
[120/1] via 10.1.3.1, 00:00:06, Serial0/0/1
from Corp
172.16.0.0/24 is subnetted, 1 subnets
S 172.16.10.0 [150/0] via 10.1.3.1
C 192.168.10.0/24 is directly connected, FastEthernet0/0
C 192.168.20.0/24 is directly connected, FastEthernet0/1
R 192.168.30.0/24 [120/2] via 10.1.3.1, 00:00:06, Serial0/0/1
[120/2] via 10.1.2.1, 00:00:06, Serial0/0/0
R 192.168.40.0/24 [120/2] via 10.1.2.1, 00:00:06, Serial0/0/0
[120/2] via 10.1.3.1, 00:00:06, Serial0/0/1
from R2 via Corp
Now to set RIP on R3
R3(config)#
router rip
R3(config-router)#
network 10.0.0.0
R3(config-router)#
network 172.16.0.0
note that R3 is our only router with "gateway of last resort" set because we set a default route instead of static routes
As a result, we only see directly connected routes listed, along with a single "S*" for the default gateway
R3 before RIP
R3#
show ip route
Gateway of last resort is 10.1.5.1 to network 0.0.0.0
10.0.0.0/8 is variably subnetted, 2 subnets, 2 masks
C 10.1.5.0/24 is directly connected, FastEthernet0/0
L 10.1.5.2/32 is directly connected, FastEthernet0/0
172.16.0.0/16 is variably subnetted, 2 subnets, 2 masks
C 172.16.10.0/24 is directly connected, Dot11Radio0/0/0
L 172.16.10.1/32 is directly connected, Dot11Radio0/0/0
S* 0.0.0.0/0 [1/0] via 10.1.5.1
R3 after RIP
R3#
show ip route
Gateway of last resort is 10.1.5.1 to network 0.0.0.0
-------------------------------------------------------------
10.0.0.0/8 is variably subnetted, 6 subnets, 2 masks
R 10.1.1.0/24 [120/1] via 10.1.5.1, 00:00:21, FastEthernet0/0
R 10.1.2.0/24 [120/1] via 10.1.5.1, 00:00:21, FastEthernet0/0
R 10.1.3.0/24 [120/1] via 10.1.5.1, 00:00:21, FastEthernet0/0
R 10.1.4.0/24 [120/1] via 10.1.5.1, 00:00:21, FastEthernet0/0
from Corp
C 10.1.5.0/24 is directly connected, FastEthernet0/0
L 10.1.5.2/32 is directly connected, FastEthernet0/0
-------------------------------------------------------------
172.16.0.0/16 is variably subnetted, 2 subnets, 2 masks
C 172.16.10.0/24 is directly connected, Dot11Radio0/0/0
L 172.16.10.1/32 is directly connected, Dot11Radio0/0/0
R 192.168.10.0/24 [120/2] via 10.1.5.1, 00:00:21, FastEthernet0/0
R 192.168.20.0/24 [120/2] via 10.1.5.1, 00:00:21, FastEthernet0/0
From R1 via Corp
R 192.168.30.0/24 [120/2] via 10.1.5.1, 00:00:21, FastEthernet0/0
R 192.168.40.0/24 [120/2] via 10.1.5.1, 00:00:21, FastEthernet0/0
From R2 via Corp
S* 0.0.0.0/0 [1/0] via 10.1.5.1
Corp before R3 RIP
Corp#
show ip route
10.0.0.0/8 is variably subnetted, 10 subnets, 2 masks
C 10.1.1.0/24 is directly connected, Vlan1
L 10.1.1.1/32 is directly connected, Vlan1
C 10.1.2.0/24 is directly connected, Serial0/0/0
L 10.1.2.1/32 is directly connected, Serial0/0/0
C 10.1.3.0/24 is directly connected, Serial0/0/1
L 10.1.3.1/32 is directly connected, Serial0/0/1
C 10.1.4.0/24 is directly connected, Serial0/1/0
L 10.1.4.1/32 is directly connected, Serial0/1/0
C 10.1.5.0/24 is directly connected, FastEthernet0/0
L 10.1.5.1/32 is directly connected, FastEthernet0/0
172.16.0.0/24 is subnetted, 1 subnets
S 172.16.10.0/24 [150/0] via 10.1.5.2
R 192.168.10.0/24 [120/1] via 10.1.2.2, 00:00:26, Serial0/0/0
[120/1] via 10.1.3.2, 00:00:26, Serial0/0/1
R 192.168.20.0/24 [120/1] via 10.1.2.2, 00:00:26, Serial0/0/0
[120/1] via 10.1.3.2, 00:00:26, Serial0/0/1
from R1 via corp
R 192.168.30.0/24 [120/1] via 10.1.4.2, 00:00:21, Serial0/1/0
R 192.168.40.0/24 [120/1] via 10.1.4.2, 00:00:21, Serial0/1/0
from R2 via corp
Corp after R3 RIP
Corp#
show ip route
10.0.0.0/8 is variably subnetted, 10 subnets, 2 masks
C 10.1.1.0/24 is directly connected, Vlan1
L 10.1.1.1/32 is directly connected, Vlan1
C 10.1.2.0/24 is directly connected, Serial0/0/0
L 10.1.2.1/32 is directly connected, Serial0/0/0
C 10.1.3.0/24 is directly connected, Serial0/0/1
L 10.1.3.1/32 is directly connected, Serial0/0/1
C 10.1.4.0/24 is directly connected, Serial0/1/0
L 10.1.4.1/32 is directly connected, Serial0/1/0
C 10.1.5.0/24 is directly connected, FastEthernet0/0
L 10.1.5.1/32 is directly connected, FastEthernet0/0
172.16.0.0/16 is variably subnetted, 2 subnets, 2 masks
R 172.16.0.0/16 [120/1] via 10.1.5.2, 00:00:13, FastEthernet0/0
S 172.16.10.0/24 [150/0] via 10.1.5.2
from R3
R 192.168.10.0/24 [120/1] via 10.1.3.2, 00:00:13, Serial0/0/1
[120/1] via 10.1.2.2, 00:00:13, Serial0/0/0
R 192.168.20.0/24 [120/1] via 10.1.3.2, 00:00:13, Serial0/0/1
[120/1] via 10.1.2.2, 00:00:13, Serial0/0/0
from R1 via corp
R 192.168.30.0/24 [120/1] via 10.1.4.2, 00:00:24, Serial0/1/0
R 192.168.40.0/24 [120/1] via 10.1.4.2, 00:00:24, Serial0/1/0
from R2 via corp
R2 before R3 RIP
R2#
show ip route
10.0.0.0/24 is subnetted, 5 subnets
R 10.1.1.0 [120/1] via 10.1.4.1, 00:00:15, Serial0/0/0
R 10.1.2.0 [120/1] via 10.1.4.1, 00:00:15, Serial0/0/0
R 10.1.3.0 [120/1] via 10.1.4.1, 00:00:15, Serial0/0/0
from Corp
C 10.1.4.0 is directly connected, Serial0/0/0
R 10.1.5.0 [120/1] via 10.1.4.1, 00:00:15, Serial0/0/0
from Corp
172.16.0.0/24 is subnetted, 1 subnets
S 172.16.10.0 [150/0] via 10.1.4.1
R 192.168.10.0/24 [120/2] via 10.1.4.1, 00:00:15, Serial0/0/0
R 192.168.20.0/24 [120/2] via 10.1.4.1, 00:00:15, Serial0/0/0
from R1 via Corp
C 192.168.30.0/24 is directly connected, FastEthernet0/0
C 192.168.40.0/24 is directly connected, FastEthernet0/1
R2 after R3 RIP
R2#
show ip route
10.0.0.0/24 is subnetted, 5 subnets
R 10.1.1.0 [120/1] via 10.1.4.1, 00:00:20, Serial0/0/0
R 10.1.2.0 [120/1] via 10.1.4.1, 00:00:20, Serial0/0/0
R 10.1.3.0 [120/1] via 10.1.4.1, 00:00:20, Serial0/0/0
from Corp
C 10.1.4.0 is directly connected, Serial0/0/0
R 10.1.5.0 [120/1] via 10.1.4.1, 00:00:20, Serial0/0/0
from Corp
172.16.0.0/16 is variably subnetted, 2 subnets, 2 masks
R 172.16.0.0/16 [120/2] via 10.1.4.1, 00:00:20, Serial0/0/0
S 172.16.10.0/24 [150/0] via 10.1.4.1
from R3 via Corp
R 192.168.10.0/24 [120/2] via 10.1.4.1, 00:00:20, Serial0/0/0
R 192.168.20.0/24 [120/2] via 10.1.4.1, 00:00:20, Serial0/0/0
from R1 via Corp
C 192.168.30.0/24 is directly connected, FastEthernet0/0
C 192.168.40.0/24 is directly connected, FastEthernet0/1
R1 before R3 RIP
R1#
show ip route
10.0.0.0/24 is subnetted, 5 subnets
R 10.1.1.0 [120/1] via 10.1.2.1, 00:00:04, Serial0/0/0
[120/1] via 10.1.3.1, 00:00:04, Serial0/0/1
C 10.1.2.0 is directly connected, Serial0/0/0
C 10.1.3.0 is directly connected, Serial0/0/1
R 10.1.4.0 [120/1] via 10.1.2.1, 00:00:04, Serial0/0/0
[120/1] via 10.1.3.1, 00:00:04, Serial0/0/1
R 10.1.5.0 [120/1] via 10.1.2.1, 00:00:04, Serial0/0/0
[120/1] via 10.1.3.1, 00:00:04, Serial0/0/1
from Corp
172.16.0.0/24 is subnetted, 1 subnets
S 172.16.10.0 [150/0] via 10.1.3.1
C 192.168.10.0/24 is directly connected, FastEthernet0/0
C 192.168.20.0/24 is directly connected, FastEthernet0/1
R 192.168.30.0/24 [120/2] via 10.1.2.1, 00:00:04, Serial0/0/0
[120/2] via 10.1.3.1, 00:00:04, Serial0/0/1
R 192.168.40.0/24 [120/2] via 10.1.2.1, 00:00:04, Serial0/0/0
[120/2] via 10.1.3.1, 00:00:04, Serial0/0/1
from R2 via Corp
R1 after R3 RIP
R1#
show ip route
10.0.0.0/24 is subnetted, 5 subnets
R 10.1.1.0 [120/1] via 10.1.3.1, 00:00:03, Serial0/0/1
[120/1] via 10.1.2.1, 00:00:03, Serial0/0/0
C 10.1.2.0 is directly connected, Serial0/0/0
C 10.1.3.0 is directly connected, Serial0/0/1
R 10.1.4.0 [120/1] via 10.1.3.1, 00:00:03, Serial0/0/1
[120/1] via 10.1.2.1, 00:00:03, Serial0/0/0
R 10.1.5.0 [120/1] via 10.1.3.1, 00:00:03, Serial0/0/1
[120/1] via 10.1.2.1, 00:00:03, Serial0/0/0
from Corp
172.16.0.0/16 is variably subnetted, 2 subnets, 2 masks
R 172.16.0.0/16 [120/2] via 10.1.3.1, 00:00:03, Serial0/0/1
[120/2] via 10.1.2.1, 00:00:03, Serial0/0/0
S 172.16.10.0/24 [150/0] via 10.1.3.1
from R3 via Corp
C 192.168.10.0/24 is directly connected, FastEthernet0/0
C 192.168.20.0/24 is directly connected, FastEthernet0/1
R 192.168.30.0/24 [120/2] via 10.1.3.1, 00:00:03, Serial0/0/1
[120/2] via 10.1.2.1, 00:00:03, Serial0/0/0
R 192.168.40.0/24 [120/2] via 10.1.3.1, 00:00:03, Serial0/0/1
[120/2] via 10.1.2.1, 00:00:03, Serial0/0/0
from R2 via Corp
Verifying Configurations
in addition to
show ip route
we can also use
show ip protocols
and
debug rip ip
Corp#
show ip protocols
Routing Protocol is "rip"
Sending updates every 30 seconds, next due in 11 seconds
Invalid after 180 seconds, hold down 180, flushed after 240
Outgoing update filter list for all interfaces is not set
Incoming update filter list for all interfaces is not set
Redistributing: rip
Default version control: send version 1, receive any version
Interface Send Recv Triggered RIP Key-chain
Vlan1 1 2 1
FastEthernet0/0 1 2 1
Serial0/0/1 1 2 1
Serial0/1/0 1 2 1
Serial0/0/0 1 2 1
Automatic network summarization is in effect
Maximum path: 4
Routing for Networks:
10.0.0.0
Passive Interface(s):
Routing Information Sources:
Gateway Distance Last Update
10.1.5.2 120 00:00:00
10.1.3.2 120 00:00:10
10.1.2.2 120 00:00:10
10.1.4.2 120 00:00:20
Distance: (default is 120)
R3#
debug ip rip
R3#RIP: received v1 update from 10.1.5.1 on FastEthernet0/0
10.1.1.0 in 1 hops
10.1.2.0 in 1 hops
10.1.3.0 in 1 hops
10.1.4.0 in 1 hops
192.168.10.0 in 2 hops
192.168.20.0 in 2 hops
192.168.30.0 in 2 hops
192.168.40.0 in 2 hops
R3#RIP: sending v1 update to 255.255.255.255 via Dot11Radio0/0/0 (172.16.10.1)
RIP: build update entries
network 10.0.0.0 metric 1
network 192.168.10.0 metric 3
network 192.168.20.0 metric 3
network 192.168.30.0 metric 3
network 192.168.40.0 metric 3
RIP: sending v1 update to 255.255.255.255 via FastEthernet0/0 (10.1.5.2)
RIP: build update entries
network 172.16.0.0 metric 1
output loops until manually disabled..............
R3#
undebug all
All possible debugging has been turned off
Note that due to the Split Horizon rule, R3 is not sending all of it's known RIP data to Corp.
It is sending all known RIP data out of the wifi interface (even there though there's no router that way),
but it is ONLY sending data about the wifi network back to Corp; data that Corp doesnt already have
Now lets look at some examples with sample routers..
I got hung up on these two examples because I found the
wording to be a bit confusing. Also there was subnetting involved that I was able to figure out, but threw me at first
First source of confusion- we have two seperate examples, and I was mixing them up.
The examples are:
Use the debug ip rip command to both:
discover a problem
and figure out how RIP was configured on a router from a different sample network
The conclusion regarding 'figuring out how RIP is configured' on this router, is that RIP networks are set as 10.0.0.0 and 172.16.0.0.
We determined that we are not the 'first source' of info on the 192.168.1.0 nertwork, since it is a metric of 2. We are sending out RIP data on that network,
but that RIP data is made availbale to us via another router.
I also got tripped up on the fact that RA is sending out S0/0 which corresponds 10.0.8.1,
and then receiving on the same interface S0/0 from an ip address of 10.0.15.0 on the other side of the link
I was able to determine that these two address are actually on the same subnet. My initial assumption was that the network address for the link is 10.0.0.0.
The problem doesn't give the subnet mask- I guessed it as /20 by using a 16 block since we can see that the third octet seems to move in 8's
if the network starts at 10.0.0.0 and we use /20 with 16 block, we would indeed have a last host address of 10.0.15.254, so 10.0.15.2 would be a valid host.
So there was a twist to this problem which needed subnetting to solve. It wasnt particulary releveant to the subject of RIP, but I was curious why the address on
the other side of that link looked so strange.
The problem also points out that we can determine there are 'at least' two routers participating in RIP here since we are sending RIP data out two interfaces but
only receiving RIP data on one interface. I'm unclear on why its worded this way; we know we are a RIP router- the fact that we are receiving data on one interface
would suggest there is 'at least one more' RIP router out there.
that's it for this example. Back to the original statement-
Use the debug ip rip command to both discover a problem and figure out
how RIP was configured on a router from a different sample network
We just 'figured out how RIP was configured on a router'.. The second example is regarding 'discovering a problem', although it is mentioned first.
The second example will use debug ip rip and show ip route to find a problem with the network
it looks like RIP data for 172.16.20.0 was received on S0/0, and then that interface was bumped out of the routing table entry for that network in favor of a static route.
ok, moving on now to RIP V2
RIP V2
enable it on all four routers
Corp(config)
router rip
Corp(config-router)
version 2
R1(config)
router rip
R1(config-router)
version 2
R2(config)
router rip
R2(config-router)
version 2
R3(config)
router rip
R3(config-router)
version 2
We'll use R1 to compare RIPv1 and RIPv2
RIPv1
R1(config)
debug ip rip
R1#RIP: sending v1 update to 255.255.255.255 via FastEthernet0/0 (192.168.10.1)
RIP: build update entries
network 10.0.0.0 metric 1
network 172.16.0.0 metric 3
network 192.168.20.0 metric 1
network 192.168.30.0 metric 3
network 192.168.40.0 metric 3
RIP: sending v1 update to 255.255.255.255 via FastEthernet0/1 (192.168.20.1)
RIP: build update entries
network 10.0.0.0 metric 1
network 172.16.0.0 metric 3
network 192.168.10.0 metric 1
network 192.168.30.0 metric 3
network 192.168.40.0 metric 3
RIP: sending v1 update to 255.255.255.255 via Serial0/0/0 (10.1.2.2)
RIP: build update entries
network 10.1.3.0 metric 1
network 192.168.10.0 metric 1
network 192.168.20.0 metric 1
RIP: sending v1 update to 255.255.255.255 via Serial0/0/1 (10.1.3.2)
RIP: build update entries
network 10.1.2.0 metric 1
network 192.168.10.0 metric 1
network 192.168.20.0 metric 1
RIPv2
R1(config)
debug ip rip
R1#RIP: sending v2 update to 224.0.0.9 via FastEthernet0/0 (192.168.10.1)
RIP: build update entries
10.0.0.0/8 via 0.0.0.0, metric 1, tag 0
172.16.0.0/16 via 0.0.0.0, metric 3, tag 0
192.168.20.0/24 via 0.0.0.0, metric 1, tag 0
192.168.30.0/24 via 0.0.0.0, metric 3, tag 0
192.168.40.0/24 via 0.0.0.0, metric 3, tag 0
RIP: sending v2 update to 224.0.0.9 via FastEthernet0/1 (192.168.20.1)
RIP: build update entries
10.0.0.0/8 via 0.0.0.0, metric 1, tag 0
172.16.0.0/16 via 0.0.0.0, metric 3, tag 0
192.168.10.0/24 via 0.0.0.0, metric 1, tag 0
192.168.30.0/24 via 0.0.0.0, metric 3, tag 0
192.168.40.0/24 via 0.0.0.0, metric 3, tag 0
RIP: sending v2 update to 224.0.0.9 via Serial0/0/0 (10.1.2.2)
RIP: build update entries
10.1.3.0/24 via 0.0.0.0, metric 1, tag 0
192.168.10.0/24 via 0.0.0.0, metric 1, tag 0
192.168.20.0/24 via 0.0.0.0, metric 1, tag 0
RIP: sending v2 update to 224.0.0.9 via Serial0/0/1 (10.1.3.2)
RIP: build update entries
10.1.2.0/24 via 0.0.0.0, metric 1, tag 0
192.168.10.0/24 via 0.0.0.0, metric 1, tag 0
192.168.20.0/24 via 0.0.0.0, metric 1, tag 0
R1(config)
show ip protocols
Routing Protocol is "rip"
Sending updates every 30 seconds, next due in 13 seconds
Invalid after 180 seconds, hold down 180, flushed after 240
Outgoing update filter list for all interfaces is not set
Incoming update filter list for all interfaces is not set
Redistributing: rip
Default version control: send version 2, receive 2
Interface Send Recv Triggered RIP Key-chain
FastEthernet0/0 2 2
FastEthernet0/1 2 2
Serial0/0/0 2 2
Serial0/0/1 2 2
Automatic network summarization is in effect
Maximum path: 4
Routing for Networks:
10.0.0.0
192.168.10.0
192.168.20.0
Passive Interface(s):
Routing Information Sources:
Gateway Distance Last Update
10.1.3.1 120 00:00:21
10.1.2.1 120 00:00:21
Distance: (default is 120)
final task of this chapter
Enable a default route out to the internet , and advertise via RIP
R3(config)#
interface s0/1/0 (this is only for example, so I am not adding a serial card to R3)
R3(config-if)#
ip addr 172.16.10.5 255.255.255.252
R3(config-if)#
exit
R3(config)#
ip route 0.0.0.0 0.0.0.0 s0/0
R3(config)#
ip default-network 172.16.0.0 tells other routers via RIP that default WAN route is through R3
Chapter 8 Exam Essentials IP Routing
1. Describe the Basic IP routing process
frame changes at each hop, but packet doesnt change EXCEPT that the TTL field in the IP header decrements
2. List the information required by a router to successfully route packets
destination IP address, location of other routers, possible routers to all remote networks,
the best route to each network, how to maintain and maintain routing info
3. Describe how MAC addresses are used during the routing process
a MAC will never pass a router interface. MACs will change between router interfaces
4. View and interpret the routing table of a router
use show ip route to see the table
a "C" indicates directly connected, an "R" indicates RIP provided the route info, "S" means static
5. differentiate the three types of routing
static- manually configured
dynamic- routers automatically share info via protocol
default- a special route is configured for all traffic without a more specific destination network found in the table
6. Compare and contrast static and dynamic routing
static routing creates no routing update traffic which means less overhead on the routers and links- but it must be
configured manually and can't react if links are lost.
dynamic routing creates update traffic, but it can react to outages and choose the best route when multiple routes exist to the same network
7. Configure static routes at the CLI
route [dest network] [mask] [next hop address OR exit interface] [admin distance] [permanent]
Ex:
Corp(config)#
ip route 192.168.10.0 255.255.255.0 10.1.2.2 150
8. Create a default route
ip route 0.0.0.0 0.0.0.0 [ip address OR exit interface]
Ex:
R3(config)#
ip route 0.0.0.0 0.0.0.0 10.1.5.1 (ingress at Corp router- use if R3 cant identify route)
9. Understand administrative distance and its role in the selection of the best route
an integer from 0 (most trusted) to 255 (no traffic will pass via this route).
All routing protocols are assigned an AD but it can be changed at the CLI
10. Differentiate distance-vector, link-state, and hybrid routing protocols
distance vector- based on hop count (RIP)
link-state- multiple factors such as bandwidth and delay
hybrid- uses both
11. List mechanisms used to prevent routing loops in the network
max hop count, split horizon, route poisoning, holddown counters
12. Describe the counts used the operation of RIP
route update timer- (30) interval between routing updates
route invalid timer- (180, update x 3) before a route is determined invalid
holddown timer-(180) time info is supressed when a link is lost
route flush timer- (240) seconds before invalid and removal
13. Configure RIP routing
router rip
network x.x.x.x
the network(s) you want to advertise from your router. It only works if the other router has RIP enabled.
By enabling RIP, you are able to RECEIVE RIP data from other RIP routers.
by specifying a network, you are SENDING RIP data on that network
14. Identify commands used to verify RIP routing
show ip route will provide contents of the routing table with codes (R, C, S)
debug ip rip will show RIP updates being sent and received
15. Describe the differences between RIPv1 and RIPv2
RIPv1 sends a broadcast (255.255.255.255) every 30 seconds and has an AD of 120.
RIPv1 is classful only, does not send any mask info. No authentication between routers.
RIPv2 sends multicasts (224.0.0.9) every 30 seconds and sends mask info, which allows it to support classless networking, RIPv2 also supports
autentication between routers.
Chapter 8 Written Lab 8.0
1. At the appropriate prompt, create a static route to network 172.16.10.0/24 with a next-hop
gateway of 172.16.20.1 and an administrative distance of 150.
Router(config)#
ip route 172.16.10.0 255.255.255.0 172.16.20.1 150
2. When a PC sends a packet to another PC in a remote network, what destination IP address and MAC address will
be in the frame that it sends to it's default gateway?
the gateway interface MAC and the remote PC's IP
3. At the appropriate prompt, create a default route to 172.16.40.1
Router(config)#
ip route 0.0.0.0 0.0.0.0 172.16.40.1
"to" is the wrong word.. we are going TO any route VIA 172.16.40.1
4. If you are using default routing in a classless environment, what command must also be used?
Router(config)#
ip classless
5. On which type of network is a default route most beneficial?
stub
6. At the appropriate prompt, display the routing table on your router
Router#
show ip route
7. When creating a static or default route, you dont have to use the next-hop ip address;
you can instead use the ____________
exit interface
8. True/False: To reach a destination host, you must know the MAC address of the remote host
false, you need the MAC of your router
9. True/False: To reach a destination host, you must know the IP address of the remote host
true
10. At the appropriate prompt, execute the command required on a DCE serial interface that is not required
on a DTE serial interface
Router(config-if)#
clock rate X
11. At the appropriate prompt, enable RIP routing on the interface with the IP address 10.0.0.1/24
Router(config)#
router rip
Router(config-router)#
network 10.0.0.0
RIPv1 is CLASSFUL only... use the classful mask based on the first octet given
12. At the appropriate prompt, prevent a router from propagating IP information out serial 1
Router(config)#
router rip
Router(config-router)#
passive-interface S0/1
can receive RIP data but will not send
13. What routing loop prevention mechanism sends out a maximum hop count as soon as a link fails?
route poisoning
14. What routing loop prevention mechanism suppresses the resending of routing information to an interface
through which it was received?
split horizon
15. At the appropriate prompt display RIP routing updates as they are sent and received on the router
to the console session
Router#
debug ip rip
to turn it off:
Router#
undebug all
Chapter 8 Hands-on Labs
For these labs we will need a network with three routers.
Lab 8.1 Creating Static routes
first set the interfaces, then program the static routes
LabA(config)#
int s0/0/0
LabA(config-if)#
ip addr 172.16.20.1
LabA(config-if)#
int f0/0
LabA(config-if)#
ip addr 172.16.10.1
-----------------------------------------------------------------
LabA(config)#
ip route 172.16.30.0 255.255.255.0 172.16.20.2
LabA(config)#
ip route 172.16.40.0 255.255.255.0 172.16.20.2
LabB(config)#
int s0/0/0
LabB(config-if)#
ip addr 172.16.20.2
LabB(config-if)#
int s0/0/1
LabB(config-if)#
ip addr 172.16.30.1
-----------------------------------------------------------------
LabB(config)#
ip route 172.16.10.0 255.255.255.0 172.16.20.1
LabB(config)#
ip route 172.16.40.0 255.255.255.0 172.16.30.2
LabC(config)#
int s0/0/0
LabC(config-if)#
ip addr 172.16.30.2
LabC(config-if)#
int f0/0
LabC(config-if)#
ip addr 172.16.40.1
-----------------------------------------------------------------
LabC(config)#
ip route 172.16.10.0 255.255.255.0 172.16.30.1
LabC(config)#
ip route 172.16.20.0 255.255.255.0 172.16.30.1
Lab 8.2 RIP Configuration
remove the static routes, enable and configure RIP with the classful network id that covers the routes you want to advertise
LabA(config)#
no ip route 172.16.30.0 255.255.255.0 172.16.20.2
LabA(config)#
no ip route 172.16.40.0 255.255.255.0 172.16.20.2
LabA(config)#
router rip
LabA(config-router)#
network 172.16.0.0
LabA(config-router)#
do show ip route
Gateway of last resort is not set
172.16.0.0/16 is variably subnetted, 5 subnets, 2 masks
C 172.16.10.0/24 is directly connected, FastEthernet0/0
L 172.16.10.1/32 is directly connected, FastEthernet0/0
C 172.16.20.0/24 is directly connected, Serial0/0/0
L 172.16.20.1/32 is directly connected, Serial0/0/0
R 172.16.30.0/24 [120/1] via 172.16.20.2, 00:00:07, Serial0/0/0
from Lab B
LabB(config)#
no ip route 172.16.10.0 255.255.255.0 172.16.20.1
LabB(config)#
no ip route 172.16.40.0 255.255.255.0 172.16.30.2
LabB(config)#
router rip
LabB(config-router)#
network 172.16.0.0
LabB(config-router)#
do show ip route
Gateway of last resort is not set
172.16.0.0/16 is variably subnetted, 5 subnets, 2 masks
R 172.16.10.0/24 [120/1] via 172.16.20.1, 00:00:13, Serial0/0/0
from LabA
C 172.16.20.0/24 is directly connected, Serial0/0/0
L 172.16.20.2/32 is directly connected, Serial0/0/0
C 172.16.30.0/24 is directly connected, Serial0/0/1
L 172.16.30.1/32 is directly connected, Serial0/0/1
LabC(config)#
no ip route 172.16.10.0 255.255.255.0 172.16.30.1
LabC(config)#
no ip route 172.16.20.0 255.255.255.0 172.16.30.1
LabC(config)#
router rip
LabC(config-router)#
network 172.16.0.0
LabC(config-router)#
do show ip route
Gateway of last resort is not set
172.16.0.0/16 is variably subnetted, 3 subnets, 2 masks
R 172.16.20.0/24 [120/1] via 172.16.30.1, 00:00:05, Serial0/0/0
from LabB
C 172.16.30.0/24 is directly connected, Serial0/0/0
L 172.16.30.2/32 is directly connected, Serial0/0/0
Chapter 8 Review Questions
1. The Acme company uses a router named Gateway to connect to its ISP. The address of the ISP router is 206.143.5.2.
Which three commands could be configured on the gateway router to allow internet access to the entire network?
Set a default route:
Gateway(config)#
ip route 0.0.0.0 0.0.0.0 206.143.5.2 next hop IP
Gateway(config)#
ip route 0.0.0.0 0.0.0.0 S/0 exit interface instead of next hop IP
Gateway(config)#
ip default-network 206.143.5.0 next hop IP
2. What command will prevent RIP routing updates from exiting an interface but will sill allow the interface to receive RIP updates?
Router(config-if)#
passive-interface
3. Which two statemnts are true about ip route 172.16.4.0 255.255.255.0 192.168.4.2?
the command establishes a static route
the default admin distance is used (since we didnt give an AD argument)
4. What two destination addresses will be used by HostA to send data to the HTTPS server as shown in the following network?
MAC of RouterA f0/0 interface
IP address of the server
5. Which two statements are true about this output?
RIP: received v1 update from 192.168.40.2 on S0/1
192.168.50.0 in 16 hops (inaccessible)
RIP: sending v1 update to 255.255.255.255 via F0/0 (192.168.30.1)
RIP: build update entries
network 192.168.20.0 metric 1
network 192.168.40.0 metric 1
network 192.168.50.0 metric 16
RIP: sending v1 update to 255.255.255.255 via S0/1 (192.168.40.1)
true:
there are at least two routers exchanging information
192.168.40.2 will be successful
FALSE
there are three interfaces on the router participating in this update
false because we only see two interfaces represented in the output: S0/1(twice) and F0/0
a ping to 192.168.50.1 will be successful
false because that route has a metric of 16; it's unreachable
6. Describe split horizon
will not advertise a route back the the same router it was learned from
7. Which would be true if HostA is trying to communicate to HostB and interface F0/0 of RouterC goes down, as shown in the graphic?
RouterC will send an ICMP 'destination unreachable type' message to inform HostA that HostB is unreachable
8. Which two statements are true regarding classless routing protocols?
VLSM is permitted
RIPv2 supports classless
9. Which two are true regarding distance-vector vs link-state?
Distance vector sends the whole routing table out all active interfaces(even if a router isnt on the other end)at periodic time intervals
Link-state sends updates containing the state of its own links to all routers in the inter-network
10. Which command display RIP routing updates?
debug ip rip
11. What does RIPv2 use to prvent routing loops?
split horizon stops an update from being send on the same interface it was received
holdown timers allow time for a network to become stable in the case of a flapping link
12. A network administrator views the output from the show ip route command. A network that is advertised
by both RIP and EIGRP appears in the routing table flagged an EIGRP route. Why is the RIP route to this network not used in this routing table?
EIGRP has a lower AD.
RIP=120
OSPP=110
IGRP=110
EIGRP=90
13. You type debug ip rip on your router console and see that 172.16.10.0 is being advertised to you with a metric of 16. What does this mean?
it is inaccessible. in RIP if you see a route advertised with a metric of 16, it's inaccessible
14. What metric does RIPv2 use to find the best path to the remote network?
distance aka hop count
15. The Corporate router receives an IP packet with a source IP address of 192.168.214.20 and a destination address of 192.168.22.3. Looking at the output from the Corp router,
what will the router do with this packet?
Corp# show ip route
[cut]
R 192.168.215.0 [120/2] via 192.168.20.2, Serail0/0
R 192.168.115.0 [120/1] via 192.168.20.0, Serial0/0
R 192.168.30.0 [120/1] via 192.168.20.2, Serial0/0
C 192.168.20.0 is directly connected, Serial0/0
C 192.168.214.0 is directly connected, FastEthernet0/0
Since there is no route to that network, the router will discard the packet and send an ICMP destination unreachable message out F0/0 back the the source network
16. If your routing table has a static, a RIP and an EIGRP route to the same network, which route will be used by default?
Static routes have an admin distance of 1 by default. Unless you change it, a static route will always be used over any other
dynamically learned route.
17. You have the following routing table. Which network will NOT be placed in the neighbor routing table?
R 192.168.30.0/24 [120/1] via 192.168.40.1, Serial 0
C 192.168.40.0/24 is directly connected, Serial 0
172.16.0.0/2 is subnetted, 1 subnets
C 172.16.30.0 is directly connected, Loopback0
R 192.168.20.0/24 [120/1] via 192.168.40.1, Serial 0
R 10.0.0.0/8 [120/15] via 192.168.40.1, Serial 0
C 192.168.50.0/24 is directly connected, Ethernet 0
10.0.0.0 cant be placed in neighboring routing table because it is at 15 hops. 16 hops is invalid in RIP
18. Two connected routers are configured only with RIP. What will be the result when a router receives a routing update that contains a
higher-cost path to a network already in it's routing table?
The router will ignore the update because it is higher cost. When a routing update is received, the router first checks the AD and always chooses
the route with the lowest AD.
19.Which is true about route poisoning?
The router sets the metric for a downed link to "infinity".
20. Which is true about RIPv2?
it has all the same timers as RIPv1
------------------------------------------------------------------------------
END CHAPTER 8
54 hours 1-28 thru 2-14-22
original total 143 hours
11.5 hours review 12-23,24,26-22
review total hours 32
book page 428/822
avg 20 min/page (reading and exercises/labs)
Chapter 9 EIGRP and OSPF
pages 427-502, start 2-14-22-M
What is EIGRP?
Note it's not officially on CCNA 200-301 but it is still important to learn
Enhanced IGRP is a classless, enchanced distance vector protocol that uses the concept of an autonomous system to describe
the set of contigous routers that run the same routing protocol and share routing information.
Features:
Support for IP and IPv6 via protocol-dependent modules (seperate routing tables)
Considered classless
Support for summaries and discontiguous networks
Eficient neighbor discovery
communication via RTP- Reliable Transport Protocol
best path selection via Diffusing Updae Algorithm DUAL
Cisco considers EIGRP a "distance-vector" routing protocol
or an "advanced distance-vector" protocol
or a "hybrid" protocol
Configuring EIGRP on our network
------------------------------------------------------------------------------------------------------------------------------------
Corp(config)#
router eigrp ?
<1-65535> Autonomous system number
Corp(config)#
router eigrp 10
R2(config-router)#
network 10.0.0.0
after eigrp on R1- links from Corp to R1 are up
%DUAL-5-NBRCHANGE: IP-EIGRP 10: Neighbor 10.1.3.2 (Serial0/0/1) is up: new adjacency
%DUAL-5-NBRCHANGE: IP-EIGRP 10: Neighbor 10.1.2.2 (Serial0/0/0) is up: new adjacency
after eigrp on R2- link from Corp to R2 is up
%DUAL-5-NBRCHANGE: IP-EIGRP 10: Neighbor 10.1.4.2 (Serial0/1/0) is up: new adjacency
after eigrp on R3- link from Corp to R3 is up
%DUAL-5-NBRCHANGE: IP-EIGRP 10: Neighbor 10.1.5.2 (FastEthernet0/0) is up: new adjacency
------------------------------------------------------------------------------------------------------------------------------------
R1(config)#
router eigrp 10
R1(config-router)#
network 10.0.0.0
after eigrp on R1- link from R1 to Corp is up
%DUAL-5-NBRCHANGE: IP-EIGRP 10: Neighbor 10.1.3.1 (Serial0/0/1) is up: new adjacency
%DUAL-5-NBRCHANGE: IP-EIGRP 10: Neighbor 10.1.2.1 (Serial0/0/0) is up: new adjacency
R1(config-router)#
network 192.168.10.0
R1(config-router)#
network 192.168.20.0
------------------------------------------------------------------------------------------------------------------------------------
R2(config)#
router eigrp 10
R2(config-router)#
network 10.0.0.0
after eigrp on R2- link from R2 to Corp is up
%DUAL-5-NBRCHANGE: IP-EIGRP 10: Neighbor 10.1.4.1 (Serial0/0/0) is up: new adjacency
R1(config-router)#
network 192.168.30.0
R1(config-router)#
network 192.168.40.0
------------------------------------------------------------------------------------------------------------------------------------
R3(config)#
router eigrp 10
R3(config-router)#
network 10.0.0.0
after eigrp on R3- link from R3 to Corp is up
%DUAL-5-NBRCHANGE: IP-EIGRP 10: Neighbor 10.1.5.1 (FastEthernet0/0) is up: new adjacency
R1(config-router)#
network 172.16.0.0
------------------------------------------------------------------------------------------------------------------------------------
Corp#
show ip route
Gateway of last resort is not set
Gateway of last resort is not set
10.0.0.0/8 is variably subnetted, 10 subnets, 2 masks
C 10.1.1.0/24 is directly connected, Vlan1
L 10.1.1.1/32 is directly connected, Vlan1
C 10.1.2.0/24 is directly connected, Serial0/0/0
L 10.1.2.1/32 is directly connected, Serial0/0/0
C 10.1.3.0/24 is directly connected, Serial0/0/1
L 10.1.3.1/32 is directly connected, Serial0/0/1
C 10.1.4.0/24 is directly connected, Serial0/1/0
L 10.1.4.1/32 is directly connected, Serial0/1/0
C 10.1.5.0/24 is directly connected, FastEthernet0/0
L 10.1.5.1/32 is directly connected, FastEthernet0/0
172.16.0.0/16 is variably subnetted, 2 subnets, 2 masks
R 172.16.0.0/16 [120/1] via 10.1.5.2, 00:00:17, FastEthernet0/0
D 172.16.10.0/24 [90/28160] via 10.1.5.2, 00:00:16, FastEthernet0/0
via R3
D 192.168.10.0/24 [90/2172416] via 10.1.2.2, 00:19:13, Serial0/0/0
[90/2172416] via 10.1.3.2, 00:19:13, Serial0/0/1
D 192.168.20.0/24 [90/2172416] via 10.1.3.2, 00:19:05, Serial0/0/1
[90/2172416] via 10.1.2.2, 00:19:05, Serial0/0/0
via R1
D 192.168.30.0/24 [90/2172416] via 10.1.4.2, 00:01:31, Serial0/1/0
D 192.168.40.0/24 [90/2172416] via 10.1.4.2, 00:01:08, Serial0/1/0
via R2
The "D" routes are for DUAL- Diffusing Update Algorithm, indicating they are EIGRP routes.
Note that we have RIP and EIGRP set currently
------------------------------------------------------------------------------------------------------------------------------------
R1#
show ip route
Gateway of last resort is not set
10.0.0.0/8 is variably subnetted, 6 subnets, 2 masks
D 10.0.0.0/8 is a summary, 00:25:28, Null0
D 10.1.1.0/24 [90/27769856] via 10.1.2.1, 00:31:33, Serial0/0/0
[90/27769856] via 10.1.3.1, 00:31:30, Serial0/0/1
via Corp
C 10.1.2.0/24 is directly connected, Serial0/0/0
C 10.1.3.0/24 is directly connected, Serial0/0/1
D 10.1.4.0/24 [90/2681856] via 10.1.2.1, 00:31:33, Serial0/0/0
[90/2681856] via 10.1.3.1, 00:31:30, Serial0/0/1
D 10.1.5.0/24 [90/2172416] via 10.1.2.1, 00:31:33, Serial0/0/0
[90/2172416] via 10.1.3.1, 00:31:30, Serial0/0/1
via Corp
172.16.0.0/16 is variably subnetted, 2 subnets, 2 masks
R 172.16.0.0/16 [120/2] via 10.1.2.1, 00:00:07, Serial0/0/0
[120/2] via 10.1.3.1, 00:00:07, Serial0/0/1
D 172.16.10.0/24 [90/2172416] via 10.1.2.1, 00:06:31, Serial0/0/0
[90/2172416] via 10.1.3.1, 00:06:31, Serial0/0/1
via Corp
C 192.168.10.0/24 is directly connected, FastEthernet0/0
C 192.168.20.0/24 is directly connected, FastEthernet0/1
D 192.168.30.0/24 [90/2684416] via 10.1.3.1, 00:07:46, Serial0/0/1
[90/2684416] via 10.1.2.1, 00:07:46, Serial0/0/0
D 192.168.40.0/24 [90/2684416] via 10.1.2.1, 00:07:23, Serial0/0/0
[90/2684416] via 10.1.3.1, 00:07:23, Serial0/0/1
via Corp
------------------------------------------------------------------------------------------------------------------------------------
R2#
show ip route
Gateway of last resort is not set
10.0.0.0/8 is variably subnetted, 6 subnets, 2 masks
D 10.0.0.0/8 is a summary, 00:13:09, Null0
D 10.1.1.0/24 [90/27769856] via 10.1.4.1, 00:36:53, Serial0/0/0
D 10.1.2.0/24 [90/2681856] via 10.1.4.1, 00:36:53, Serial0/0/0
D 10.1.3.0/24 [90/2681856] via 10.1.4.1, 00:36:53, Serial0/0/0
via Corp
C 10.1.4.0/24 is directly connected, Serial0/0/0
D 10.1.5.0/24 [90/2172416] via 10.1.4.1, 00:36:53, Serial0/0/0
via Corp
172.16.0.0/16 is variably subnetted, 2 subnets, 2 masks
R 172.16.0.0/16 [120/2] via 10.1.4.1, 00:00:23, Serial0/0/0
D 172.16.10.0/24 [90/2172416] via 10.1.4.1, 00:11:54, Serial0/0/0
via Corp
D 192.168.10.0/24 [90/2684416] via 10.1.4.1, 00:30:51, Serial0/0/0
D 192.168.20.0/24 [90/2684416] via 10.1.4.1, 00:30:43, Serial0/0/0
via Corp
C 192.168.30.0/24 is directly connected, FastEthernet0/0
C 192.168.40.0/24 is directly connected, FastEthernet0/1
------------------------------------------------------------------------------------------------------------------------------------
R3#
show ip route
Gateway of last resort is 10.1.5.1 to network 0.0.0.0
10.0.0.0/8 is variably subnetted, 6 subnets, 2 masks
D 10.1.1.0/24 [90/25628160] via 10.1.5.1, 00:37:20, FastEthernet0/0
D 10.1.2.0/24 [90/2172416] via 10.1.5.1, 00:37:15, FastEthernet0/0
D 10.1.3.0/24 [90/2172416] via 10.1.5.1, 00:37:20, FastEthernet0/0
D 10.1.4.0/24 [90/2172416] via 10.1.5.1, 00:37:20, FastEthernet0/0
via Corp
C 10.1.5.0/24 is directly connected, FastEthernet0/0
L 10.1.5.2/32 is directly connected, FastEthernet0/0
172.16.0.0/16 is variably subnetted, 2 subnets, 2 masks
C 172.16.10.0/24 is directly connected, Dot11Radio0/0/0
L 172.16.10.1/32 is directly connected, Dot11Radio0/0/0
D 192.168.10.0/24 [90/2174976] via 10.1.5.1, 00:31:10, FastEthernet0/0
D 192.168.20.0/24 [90/2174976] via 10.1.5.1, 00:31:02, FastEthernet0/0
via Corp and R1
D 192.168.30.0/24 [90/2174976] via 10.1.5.1, 00:13:28, FastEthernet0/0
D 192.168.40.0/24 [90/2174976] via 10.1.5.1, 00:13:05, FastEthernet0/0
via Corp and R2
S* 0.0.0.0/0 [1/0] via 10.1.5.1
------------------------------------------------------------------------------------------------------------------------------------
turn off auto summary on each router
------------------------------------------------------------------------------------------------------------------------------------
Corp(config)#
router eigrp 10
Corp(config-router)#
no auto-summary
------------------------------------------------------------------------------------------------------------------------------------
R1(config)#
router eigrp 10
R1(config-router)#
no auto-summary
------------------------------------------------------------------------------------------------------------------------------------
R2(config)#
router eigrp 10
R2(config-router)#
no auto-summary
------------------------------------------------------------------------------------------------------------------------------------
R3(config)#
router eigrp 10
R3(config-router)#
no auto-summary
------------------------------------------------------------------------------------------------------------------------------------
compare Corp before and after auto summary turned off
------------------------------------------------------------------------------------------------------------------------------------
auto summary on
Corp#
show ip route
Gateway of last resort is not set
10.0.0.0/8 is variably subnetted, 10 subnets, 2 masks
C 10.1.1.0/24 is directly connected, Vlan1
L 10.1.1.1/32 is directly connected, Vlan1
C 10.1.2.0/24 is directly connected, Serial0/0/0
L 10.1.2.1/32 is directly connected, Serial0/0/0
C 10.1.3.0/24 is directly connected, Serial0/0/1
L 10.1.3.1/32 is directly connected, Serial0/0/1
C 10.1.4.0/24 is directly connected, Serial0/1/0
L 10.1.4.1/32 is directly connected, Serial0/1/0
C 10.1.5.0/24 is directly connected, FastEthernet0/0
L 10.1.5.1/32 is directly connected, FastEthernet0/0
172.16.0.0/16 is variably subnetted, 2 subnets, 2 masks
R 172.16.0.0/16 [120/1] via 10.1.5.2, 00:00:17, FastEthernet0/0
D 172.16.10.0/24 [90/28160] via 10.1.5.2, 00:00:16, FastEthernet0/0
via R3
D 192.168.10.0/24 [90/2172416] via 10.1.2.2, 00:19:13, Serial0/0/0
[90/2172416] via 10.1.3.2, 00:19:13, Serial0/0/1
D 192.168.20.0/24 [90/2172416] via 10.1.3.2, 00:19:05, Serial0/0/1
[90/2172416] via 10.1.2.2, 00:19:05, Serial0/0/0
via R1
D 192.168.30.0/24 [90/2172416] via 10.1.4.2, 00:01:31, Serial0/1/0
D 192.168.40.0/24 [90/2172416] via 10.1.4.2, 00:01:08, Serial0/1/0
via R2
auto summary off
Corp#
show ip route
Gateway of last resort is not set
10.0.0.0/8 is variably subnetted, 10 subnets, 2 masks
C 10.1.1.0/24 is directly connected, Vlan1
L 10.1.1.1/32 is directly connected, Vlan1
C 10.1.2.0/24 is directly connected, Serial0/0/0
L 10.1.2.1/32 is directly connected, Serial0/0/0
C 10.1.3.0/24 is directly connected, Serial0/0/1
L 10.1.3.1/32 is directly connected, Serial0/0/1
C 10.1.4.0/24 is directly connected, Serial0/1/0
L 10.1.4.1/32 is directly connected, Serial0/1/0
C 10.1.5.0/24 is directly connected, FastEthernet0/0
L 10.1.5.1/32 is directly connected, FastEthernet0/0
172.16.0.0/16 is variably subnetted, 2 subnets, 2 masks
R 172.16.0.0/16 [120/1] via 10.1.5.2, 00:00:12, FastEthernet0/0
D 172.16.10.0/24 [90/28160] via 10.1.5.2, 00:45:29, FastEthernet0/0
via R3
D 192.168.10.0/24 [90/2172416] via 10.1.2.2, 00:01:08, Serial0/0/0
[90/2172416] via 10.1.3.2, 00:01:08, Serial0/0/1
D 192.168.20.0/24 [90/2172416] via 10.1.2.2, 00:01:08, Serial0/0/0
[90/2172416] via 10.1.3.2, 00:01:08, Serial0/0/1
via R1
D 192.168.30.0/24 [90/2172416] via 10.1.4.2, 00:00:46, Serial0/1/0
D 192.168.40.0/24 [90/2172416] via 10.1.4.2, 00:00:46, Serial0/1/0
via R2
We are still seeing an auto summarized route- 172.16.0.0 coming from R3.
The book discusses enabling EIGRP auto summary on all four routers- nothing is said about disabling it within RIP or turning off RIP.
RIP auto summarizes by default. We cant get rid of this auto summary route while RIP is on.
Moving on...
VERIFYING EIGRP
several commands available to verify and troubleshoot
show ip route
show the entire routing table
show ip route eigrp
show only EIGRP entries in the routing table
show ip eigrp neighbors
show all EIGRP neigbors
show ip eigrp topology
show entries in the EIGRP topology table
show ip protocols
shows routing protocols configuration
debug eigrp packet
shows hello packets sent/received between adjacent routers
debug ip eigrp events
shows EIGRP changes and updates as they occur on your network
lets take a look at the state of our 4 routers. RIP and EIGRP are running on each.
Notice how this command is giving different outputs between the two different IOS versions
IOS 15.1
Corp#
show ip protocols
Routing Protocol is "eigrp 10 "
Outgoing update filter list for all interfaces is not set
Incoming update filter list for all interfaces is not set
Default networks flagged in outgoing updates
Default networks accepted from incoming updates
Redistributing: eigrp 10
EIGRP-IPv4 Protocol for AS(10)
Metric weight K1=1, K2=0, K3=1, K4=0, K5=0
NSF-aware route hold timer is 240
Router-ID: 10.1.1.1
Topology : 0 (base)
Active Timer: 3 min
Distance: internal 90 external 170
Maximum path: 4
Maximum hopcount 100
Maximum metric variance 1
Automatic Summarization: disabled
Automatic address summarization:
Maximum path: 4
Routing for Networks:
10.0.0.0
Routing Information Sources:
Gateway Distance Last Update
10.1.5.2 90 0
10.1.3.2 90 6464
10.1.2.2 90 6795
10.1.4.2 90 7955
Distance: internal 90 external 170
Routing Protocol is "rip"
Sending updates every 30 seconds, next due in 10 seconds
Invalid after 180 seconds, hold down 180, flushed after 240
Outgoing update filter list for all interfaces is not set
Incoming update filter list for all interfaces is not set
Redistributing: rip
Default version control: send version 2, receive 2
Interface Send Recv Triggered RIP Key-chain
Vlan1 2 2
FastEthernet0/0 2 2
Serial0/1/0 2 2
Serial0/0/1 2 2
Serial0/0/0 2 2
Automatic network summarization is in effect
Maximum path: 4
Routing for Networks:
10.0.0.0
Passive Interface(s):
Routing Information Sources:
Gateway Distance Last Update
10.1.5.2 120 00:00:12
10.1.3.2 120 00:00:16
10.1.2.2 120 00:00:16
10.1.4.2 120 00:00:13
Distance: (default is 120)
IOS 12.4
R1#
show ip protocols
Routing Protocol is "eigrp 10 "
Outgoing update filter list for all interfaces is not set
Incoming update filter list for all interfaces is not set
Default networks flagged in outgoing updates
Default networks accepted from incoming updates
EIGRP metric weight K1=1, K2=0, K3=1, K4=0, K5=0
EIGRP maximum hopcount 100
EIGRP maximum metric variance 1
Redistributing: eigrp 10
Automatic network summarization is not in effect
Maximum path: 4
Routing for Networks:
10.0.0.0
192.168.10.0
192.168.20.0
Routing Information Sources:
Gateway Distance Last Update
10.1.3.1 90 6465
10.1.2.1 90 6794
Distance: internal 90 external 170
Routing Protocol is "rip"
Sending updates every 30 seconds, next due in 21 seconds
Invalid after 180 seconds, hold down 180, flushed after 240
Outgoing update filter list for all interfaces is not set
Incoming update filter list for all interfaces is not set
Redistributing: rip
Default version control: send version 2, receive 2
Interface Send Recv Triggered RIP Key-chain
FastEthernet0/0 2 2
FastEthernet0/1 2 2
Serial0/0/0 2 2
Serial0/0/1 2 2
Automatic network summarization is not in effect
Maximum path: 4
Routing for Networks:
10.0.0.0
192.168.10.0
192.168.20.0
Passive Interface(s):
Routing Information Sources:
Gateway Distance Last Update
10.1.3.1 120 00:00:06
10.1.2.1 120 00:00:06
Distance: (default is 120)
IOS 12.4
R2#
show ip protocols
Routing Protocol is "eigrp 10 "
Outgoing update filter list for all interfaces is not set
Incoming update filter list for all interfaces is not set
Default networks flagged in outgoing updates
Default networks accepted from incoming updates
EIGRP metric weight K1=1, K2=0, K3=1, K4=0, K5=0
EIGRP maximum hopcount 100
EIGRP maximum metric variance 1
Redistributing: eigrp 10
Automatic network summarization is not in effect
Maximum path: 4
Routing for Networks:
10.0.0.0
192.168.30.0
192.168.40.0
Routing Information Sources:
Gateway Distance Last Update
10.1.4.1 90 7955
Distance: internal 90 external 170
Routing Protocol is "rip"
Sending updates every 30 seconds, next due in 11 seconds
Invalid after 180 seconds, hold down 180, flushed after 240
Outgoing update filter list for all interfaces is not set
Incoming update filter list for all interfaces is not set
Redistributing: rip
Default version control: send version 2, receive 2
Interface Send Recv Triggered RIP Key-chain
FastEthernet0/0 2 2
FastEthernet0/1 2 2
Serial0/0/0 2 2
Automatic network summarization is in effect
Maximum path: 4
Routing for Networks:
10.0.0.0
192.168.30.0
192.168.40.0
Passive Interface(s):
Routing Information Sources:
Gateway Distance Last Update
10.1.4.1 120 00:00:20
Distance: (default is 120)
IOS 15.1
R3#
show ip protocols
Routing Protocol is "eigrp 10 "
Outgoing update filter list for all interfaces is not set
Incoming update filter list for all interfaces is not set
Default networks flagged in outgoing updates
Default networks accepted from incoming updates
Redistributing: eigrp 10
EIGRP-IPv4 Protocol for AS(10)
Metric weight K1=1, K2=0, K3=1, K4=0, K5=0
NSF-aware route hold timer is 240
Router-ID: 10.1.5.2
Topology : 0 (base)
Active Timer: 3 min
Distance: internal 90 external 170
Maximum path: 4
Maximum hopcount 100
Maximum metric variance 1
Automatic Summarization: disabled
Automatic address summarization:
Maximum path: 4
Routing for Networks:
10.0.0.0
172.16.0.0
Routing Information Sources:
Gateway Distance Last Update
10.1.5.1 90 0
Distance: internal 90 external 170
Routing Protocol is "rip"
Sending updates every 30 seconds, next due in 27 seconds
Invalid after 180 seconds, hold down 180, flushed after 240
Outgoing update filter list for all interfaces is not set
Incoming update filter list for all interfaces is not set
Redistributing: rip
Default version control: send version 2, receive 2
Interface Send Recv Triggered RIP Key-chain
Dot11Radio0/0/0 2 2
FastEthernet0/0 2 2
Automatic network summarization is not in effect
Maximum path: 4
Routing for Networks:
10.0.0.0
172.16.0.0
Passive Interface(s):
Routing Information Sources:
Gateway Distance Last Update
10.1.5.1 120 00:00:02
Distance: (default is 120)
I'm also noticing that we have inconsistent auto-summarization settings- I was having trouble with this earlier. The book discusses
getting rid of the 172.16.0.0 summarized route in the EIGRP settings. I was not able to get rid of it, I think because RIP is still on, and RIP forces auto-summary
Part of the challenge here is that the book is strictly dealing with IOS 12.4
I will now make sure to turn auto summary off for both RIP and EIGRP on each of the four routers.
OK the part I am forgetting is that we are running RIP V2 which does not force auto-summary but runs it optionally, and we must turn it off to avoid auto summarization.
Corp(config)#
router rip
Corp(config-router)#
no auto-summary
Corp(config-router)#
router eigrp 10
Corp(config-router)#
no auto-summary
R1(config)#
router rip
R1(config-router)#
no auto-summary
R1(config-router)#
router eigrp 10
R1(config-router)#
no auto-summary
R1(config)#
router rip
R1(config-router)#
no auto-summary
R1(config-router)#
router eigrp 10
R2(config-router)#
no auto-summary
R3(config)#
router rip
R3(config-router)#
no auto-summary
R3(config-router)#
router eigrp 10
R3(config-router)#
no auto-summary
and lets see how the output looks now. This time I'll do show ip protocols and
show ip route side by side for each router
IOS 15.1
Corp#
show ip protocols
Routing Protocol is "eigrp 10 "
Outgoing update filter list for all interfaces is not set
Incoming update filter list for all interfaces is not set
Default networks flagged in outgoing updates
Default networks accepted from incoming updates
Redistributing: eigrp 10
EIGRP-IPv4 Protocol for AS(10)
Metric weight K1=1, K2=0, K3=1, K4=0, K5=0
NSF-aware route hold timer is 240
Router-ID: 10.1.1.1
Topology : 0 (base)
Active Timer: 3 min
Distance: internal 90 external 170
Maximum path: 4
Maximum hopcount 100
Maximum metric variance 1
Automatic Summarization: disabled
Automatic address summarization:
Maximum path: 4
Routing for Networks:
10.0.0.0
Routing Information Sources:
Gateway Distance Last Update
10.1.5.2 90 0
10.1.3.2 90 6464
10.1.2.2 90 6795
10.1.4.2 90 7955
Distance: internal 90 external 170
Routing Protocol is "rip" doesnt necessarily mean RIPv1
Sending updates every 30 seconds, next due in 3 seconds
Invalid after 180 seconds, hold down 180, flushed after 240
Outgoing update filter list for all interfaces is not set
Incoming update filter list for all interfaces is not set
Redistributing: rip
Default version control: send version 2, receive 2 RIPv2 is specified
Interface Send Recv Triggered RIP Key-chain
Vlan1 2 2
FastEthernet0/0 2 2
Serial0/1/0 2 2
Serial0/0/1 2 2
Serial0/0/0 2 2
Automatic network summarization is not in effect
Maximum path: 4
Routing for Networks:
10.0.0.0
Passive Interface(s):
Routing Information Sources:
Gateway Distance Last Update
10.1.5.2 120 00:00:02
10.1.3.2 120 00:00:21
10.1.2.2 120 00:00:21
10.1.4.2 120 00:00:04
Distance: (default is 120)
IOS 15.1
Corp#
show ip route
Gateway of last resort is not set
10.0.0.0/8 is variably subnetted, 10 subnets, 2 masks
C 10.1.1.0/24 is directly connected, Vlan1
L 10.1.1.1/32 is directly connected, Vlan1
C 10.1.2.0/24 is directly connected, Serial0/0/0
L 10.1.2.1/32 is directly connected, Serial0/0/0
C 10.1.3.0/24 is directly connected, Serial0/0/1
L 10.1.3.1/32 is directly connected, Serial0/0/1
C 10.1.4.0/24 is directly connected, Serial0/1/0
L 10.1.4.1/32 is directly connected, Serial0/1/0
C 10.1.5.0/24 is directly connected, FastEthernet0/0
L 10.1.5.1/32 is directly connected, FastEthernet0/0
172.16.0.0/24 is subnetted, 1 subnets
D 172.16.10.0/24 [90/28160] via 10.1.5.2, 00:57:25, FastEthernet0/0
D 192.168.10.0/24 [90/2172416] via 10.1.3.2, 00:57:20, Serial0/0/1
[90/2172416] via 10.1.2.2, 00:57:20, Serial0/0/0
D 192.168.20.0/24 [90/2172416] via 10.1.3.2, 00:57:20, Serial0/0/1
[90/2172416] via 10.1.2.2, 00:57:20, Serial0/0/0
D 192.168.30.0/24 [90/2172416] via 10.1.4.2, 00:57:19, Serial0/1/0
D 192.168.40.0/24 [90/2172416] via 10.1.4.2, 00:57:19, Serial0/1/0
IOS 12.4
R1#
show ip protocols
Routing Protocol is "eigrp 10 "
Outgoing update filter list for all interfaces is not set
Incoming update filter list for all interfaces is not set
Default networks flagged in outgoing updates
Default networks accepted from incoming updates
EIGRP metric weight K1=1, K2=0, K3=1, K4=0, K5=0
EIGRP maximum hopcount 100
EIGRP maximum metric variance 1
Redistributing: eigrp 10
Automatic network summarization is not in effect
Maximum path: 4
Routing for Networks:
10.0.0.0
192.168.10.0
192.168.20.0
Routing Information Sources:
Gateway Distance Last Update
10.1.3.1 90 6465
10.1.2.1 90 6794
Distance: internal 90 external 170
Routing Protocol is "rip"
Sending updates every 30 seconds, next due in 26 seconds
Invalid after 180 seconds, hold down 180, flushed after 240
Outgoing update filter list for all interfaces is not set
Incoming update filter list for all interfaces is not set
Redistributing: rip
Default version control: send version 2, receive 2
Interface Send Recv Triggered RIP Key-chain
FastEthernet0/0 2 2
FastEthernet0/1 2 2
Serial0/0/0 2 2
Serial0/0/1 2 2
Automatic network summarization is not in effect
Maximum path: 4
Routing for Networks:
10.0.0.0
192.168.10.0
192.168.20.0
Passive Interface(s):
Routing Information Sources:
Gateway Distance Last Update
10.1.3.1 120 00:00:03
10.1.2.1 120 00:00:03
Distance: (default is 120)
IOS 12.4
R1#
show ip route
Gateway of last resort is not set
10.0.0.0/24 is subnetted, 5 subnets
D 10.1.1.0 [90/27769856] via 10.1.3.1, 00:54:47, Serial0/0/1
[90/27769856] via 10.1.2.1, 00:54:47, Serial0/0/0
C 10.1.2.0 is directly connected, Serial0/0/0
C 10.1.3.0 is directly connected, Serial0/0/1
D 10.1.4.0 [90/2681856] via 10.1.3.1, 00:54:47, Serial0/0/1
[90/2681856] via 10.1.2.1, 00:54:47, Serial0/0/0
D 10.1.5.0 [90/2172416] via 10.1.3.1, 00:54:47, Serial0/0/1
[90/2172416] via 10.1.2.1, 00:54:47, Serial0/0/0
172.16.0.0/24 is subnetted, 1 subnets
D 172.16.10.0 [90/2172416] via 10.1.3.1, 00:54:47, Serial0/0/1
[90/2172416] via 10.1.2.1, 00:54:47, Serial0/0/0
C 192.168.10.0/24 is directly connected, FastEthernet0/0
C 192.168.20.0/24 is directly connected, FastEthernet0/1
D 192.168.30.0/24 [90/2684416] via 10.1.3.1, 00:54:46, Serial0/0/1
[90/2684416] via 10.1.2.1, 00:54:46, Serial0/0/0
D 192.168.40.0/24 [90/2684416] via 10.1.3.1, 00:54:46, Serial0/0/1
[90/2684416] via 10.1.2.1, 00:54:46, Serial0/0/0
note that the DUAL routes being advertised from the 10.0.0.0 networks are all specific to the third octet.. that's because we are reading those routes
from their source, aka the router which they are directly connected to, Corp.
and on Corp, those networks were added to the interfaces with a /24 mask.
so even though our EIGRP config doesnt specifically include /24 networks.. we told it to include anything with a 10.x.x.x
Corp is advertising to R1 our /24 network interfaces that have a 10 in the first octet, EXCEPT the two which are directly connected to R1
10.1.1.0
10.1.4.0
10.1.5.0
are assumed to be the subnets based on the info we configured, which was 10.1.4.1/24 on corp, and 10.1.4.2/24 on r2 s0/0/0
nowhere in this configuration, have we entered the 10.1.4.0 network.
EIGRP is figuring it out based on the /24 mask we gave when assiging he IPs to the interfaces
IOS 12.4
R2#
show ip protocols
Routing Protocol is "eigrp 10 "
Outgoing update filter list for all interfaces is not set
Incoming update filter list for all interfaces is not set
Default networks flagged in outgoing updates
Default networks accepted from incoming updates
EIGRP metric weight K1=1, K2=0, K3=1, K4=0, K5=0
EIGRP maximum hopcount 100
EIGRP maximum metric variance 1
Redistributing: eigrp 10
Automatic network summarization is not in effect
Maximum path: 4
Routing for Networks:
10.0.0.0
192.168.30.0
192.168.40.0
Routing Information Sources:
Gateway Distance Last Update
10.1.4.1 90 7955
Distance: internal 90 external 170
Routing Protocol is "rip"
Sending updates every 30 seconds, next due in 18 seconds
Invalid after 180 seconds, hold down 180, flushed after 240
Outgoing update filter list for all interfaces is not set
Incoming update filter list for all interfaces is not set
Redistributing: rip
Default version control: send version 2, receive 2
Interface Send Recv Triggered RIP Key-chain
FastEthernet0/0 2 2
FastEthernet0/1 2 2
Serial0/0/0 2 2
Automatic network summarization is not in effect
Maximum path: 4
Routing for Networks:
10.0.0.0
192.168.30.0
192.168.40.0
Passive Interface(s):
Routing Information Sources:
Gateway Distance Last Update
10.1.4.1 120 00:00:07
Distance: (default is 120)
IOS 12.4
R2#
show ip route
Gateway of last resort is not set
10.0.0.0/24 is subnetted, 5 subnets
D 10.1.1.0 [90/27769856] via 10.1.4.1, 00:59:10, Serial0/0/0
D 10.1.2.0 [90/2681856] via 10.1.4.1, 00:59:10, Serial0/0/0
D 10.1.3.0 [90/2681856] via 10.1.4.1, 00:59:10, Serial0/0/0
C 10.1.4.0 is directly connected, Serial0/0/0
D 10.1.5.0 [90/2172416] via 10.1.4.1, 00:59:10, Serial0/0/0
172.16.0.0/24 is subnetted, 1 subnets
D 172.16.10.0 [90/2172416] via 10.1.4.1, 00:59:10, Serial0/0/0
D 192.168.10.0/24 [90/2684416] via 10.1.4.1, 00:59:10, Serial0/0/0
D 192.168.20.0/24 [90/2684416] via 10.1.4.1, 00:59:10, Serial0/0/0
C 192.168.30.0/24 is directly connected, FastEthernet0/0
C 192.168.40.0/24 is directly connected, FastEthernet0/1
IOS 15.1
R3#
show ip protocols
Routing Protocol is "eigrp 10 "
Outgoing update filter list for all interfaces is not set
Incoming update filter list for all interfaces is not set
Default networks flagged in outgoing updates
Default networks accepted from incoming updates
Redistributing: eigrp 10
EIGRP-IPv4 Protocol for AS(10)
Metric weight K1=1, K2=0, K3=1, K4=0, K5=0
NSF-aware route hold timer is 240
Router-ID: 10.1.5.2
Topology : 0 (base)
Active Timer: 3 min
Distance: internal 90 external 170
Maximum path: 4
Maximum hopcount 100
Maximum metric variance 1
Automatic Summarization: disabled
Automatic address summarization:
Maximum path: 4
Routing for Networks:
10.0.0.0
172.16.0.0
Routing Information Sources:
Gateway Distance Last Update
10.1.5.1 90 0
Distance: internal 90 external 170
Routing Protocol is "rip"
Sending updates every 30 seconds, next due in 15 seconds
Invalid after 180 seconds, hold down 180, flushed after 240
Outgoing update filter list for all interfaces is not set
Incoming update filter list for all interfaces is not set
Redistributing: rip
Default version control: send version 2, receive 2
Interface Send Recv Triggered RIP Key-chain
Dot11Radio0/0/0 2 2
FastEthernet0/0 2 2
Automatic network summarization is not in effect
Maximum path: 4
Routing for Networks:
10.0.0.0
172.16.0.0
Passive Interface(s):
Routing Information Sources:
Gateway Distance Last Update
10.1.5.1 120 00:00:14
Distance: (default is 120)
IOS 15.1
R3#
show ip route
Gateway of last resort is 10.1.5.1 to network 0.0.0.0
10.0.0.0/8 is variably subnetted, 6 subnets, 2 masks
D 10.1.1.0/24 [90/25628160] via 10.1.5.1, 00:59:52, FastEthernet0/0
D 10.1.2.0/24 [90/2172416] via 10.1.5.1, 00:59:47, FastEthernet0/0
D 10.1.3.0/24 [90/2172416] via 10.1.5.1, 00:59:52, FastEthernet0/0
D 10.1.4.0/24 [90/2172416] via 10.1.5.1, 00:59:52, FastEthernet0/0
C 10.1.5.0/24 is directly connected, FastEthernet0/0
L 10.1.5.2/32 is directly connected, FastEthernet0/0
172.16.0.0/16 is variably subnetted, 2 subnets, 2 masks
C 172.16.10.0/24 is directly connected, Dot11Radio0/0/0
L 172.16.10.1/32 is directly connected, Dot11Radio0/0/0
D 192.168.10.0/24 [90/2174976] via 10.1.5.1, 00:59:47, FastEthernet0/0
D 192.168.20.0/24 [90/2174976] via 10.1.5.1, 00:59:47, FastEthernet0/0
D 192.168.30.0/24 [90/2174976] via 10.1.5.1, 00:59:46, FastEthernet0/0
D 192.168.40.0/24 [90/2174976] via 10.1.5.1, 00:59:46, FastEthernet0/0
S* 0.0.0.0/0 [1/0] via 10.1.5.1
Observations:
Since this is a 15.1 router, we always get a "L" local route when
we have a "C" connected route. In R3's case, the 172.16.10.0 network
is directly connected. The interface which connects it, 172.16.10.1,
counts as a "local" route. This is NOT the case on the 12.4 routers.
looking to the left, our protocol output tells us two key facts for both EIGRP and RIP:
Routing for networks:
10.0.0.0
172.16.0.0
R3 is responsible for *sending* data about these two networks to our other EIGRP routers...
"I'm R3 and I can connect you to networks on the R3
router or networks on the Corp router"
Notice how the 192 networks arent listed. R3 isnt connected to a 192 network directly, nor is it connected to a neighbor who is directly connected.
If I, as a client, am sending data to a 192 network from the 172 network, I will start
at R3. Since R3 is receiving routes for the 192 networks via Corp, I will be able to reach a 192 network via Corp.
My connection to corp will happen VIA a "10.0.0.0" route.
R3 is technically only routing for 172 and 10 networks. Beyond that, it could potentially connect to many other different networks. But in terms of the R3 routing table,
all it can offer is a path out to the 172 network or the 10 network
Routing information sources:
10.1.5.1
In this case I can see that R3 is receiving routing data from one interface only,
and that is it's link to Corp. Some of the data we are receiving from Corp actually originates
at other routers, but we cant see that here; the data comes to us from Corp, and that is all we know
EIGRP TERMINOLOGY
FEASIBLE DISTANCE (FD)
the best metric among all paths, including to the next hop neighbor. You will only see the route with the lowest FD appear in the routing table
The FD is calculated by adding the reported distance from the neighbor (AD) plus the metric to that neighbor
ADVERTISED DISTANCE (AD)
the metric of a remote network as reported by a neighbor, listed second in parenthesis in toplogy table
P 192.168.20.0/24, 2 successors, FD is 2172416
via 10.1.3.2 (2172416/28160), Serial0/0/1
feasible / advertised
Neighbor Table
each router keeps state information about adjacent neighbors.. When a new neighbor is learned, the address and interface are recorded.
The neighbor table is stored in RAM.
Sequence numbres are used to match acks with update packets. The last squence number received from a neighbor is recorded so out of order packets
can be detected
Topology Table
acted upon by DUAL Diffusing Update Alogorithm. Contains all destinations advertised by neighboring routers.
For each neighbor, the adversited distance, which comes only from that neighbor's routing table, is recorded
The feasible distance is also recorded.
Feasible Successor
a PATH whose advertised distance is less than the feasible distance of the current succesor, and is considered a backup route.
EIGRP keeps up to 16 feasible successors in the toplogy table.
The one with the best metric (The Successor) is copied and placed into the routing table
Successor
the best route to a remote network, used by EIGRP to forward traffic. It's backed up by a feasible successor, if one is available.
lets demo some more of the commands
VERIFYING EIGRP
several commands available to verify and troubleshoot
show ip route
show the entire routing table
show ip route eigrp
show only EIGRP entries in the routing table
show ip eigrp neighbors
show all EIGRP neigbors
show ip eigrp topology
show entries in the EIGRP topology table
show ip protocols
shows routing protocols configuration
debug eigrp packet
shows hello packets sent/received between adjacent routers
debug ip eigrp events
shows EIGRP changes and updates as they occur on your network
Corp#
show ip eigrp ?
interfaces IP-EIGRP interfaces
neighbors IP-EIGRP neighbors
topology IP-EIGRP Topology Table
traffic IP-EIGRP Traffic Statistics
Corp#
show ip eigrp topology
IP-EIGRP Topology Table for AS 10/ID(10.1.5.1)
Codes: P - Passive, A - Active, U - Update, Q - Query, R - Reply,
r - Reply status
P 10.1.1.0/24, 1 successors, FD is 25625600
via Connected, Vlan1
P 10.1.2.0/24, 1 successors, FD is 2169856
via Connected, Serial0/0/0
P 10.1.3.0/24, 1 successors, FD is 2169856
via Connected, Serial0/0/1
P 10.1.4.0/24, 1 successors, FD is 2169856
via Connected, Serial0/1/0
P 10.1.5.0/24, 1 successors, FD is 28160
via Connected, FastEthernet0/0
P 172.16.10.0/24, 1 successors, FD is 28160
via 10.1.5.2 (28160/25600), FastEthernet0/0
P 192.168.10.0/24, 2 successors, FD is 2172416
via 10.1.3.2 (2172416/28160), Serial0/0/1
via 10.1.2.2 (2172416/28160), Serial0/0/0
P 192.168.20.0/24, 2 successors, FD is 2172416
via 10.1.3.2 (2172416/28160), Serial0/0/1
via 10.1.2.2 (2172416/28160), Serial0/0/0
P 192.168.30.0/24, 1 successors, FD is 2172416
via 10.1.4.2 (2172416/28160), Serial0/1/0
P 192.168.40.0/24, 1 successors, FD is 2172416
via 10.1.4.2 (2172416/28160), Serial0/1/0
the "P" preceding each entry is for PASSIVE
these routes are in a passive state, which is good
if they move to an ACTIVE state, it means the have lost their path in the network and looking for a replacement.
Each entry also shows the FEASIBLE DISTANCE, the next hop address, and the local egress interface
Corp#
show ip eigrp neighbors
IP-EIGRP neighbors for process 10
H Address Interface Hold Uptime SRTT RTO Q Seq
(sec) (ms) Cnt Num
0 10.1.5.2 Fa0/0 14 02:00:05 40 1000 0 19
1 10.1.3.2 Se0/0/1 13 01:59:59 40 1000 0 14
2 10.1.2.2 Se0/0/0 13 01:59:59 40 1000 0 13
3 10.1.4.2 Se0/1/0 12 01:59:57 40 1000 0 15
fields:
H - the order in which the neighbors were discovered
hold - how long the router will wait for a hello packet
uptime - how long the neigborship has been established
SRTT - smooth round trip timer - the time it takes for a round trip from this router, to neighbor, and back.
SRTT is used to determine how long to wait for a MULTICAST reply.
if a reply isnt received in time, the router switches to UNICASTS
RTO - Retransmission Time Out- is the time EIGRP waits before retransmitting a packet from the retransmission queue
Q - indicates wheter there are oustanding messages in the queue
Seq - indicates the sequence number of the last update from that neighbor. This is used to maintain syncrhonization and avoid duplicate
or out-of-sequence processing of messages
Corp#
show ip route eigrp
172.16.0.0/24 is subnetted, 1 subnets
D 172.16.10.0 [90/28160] via 10.1.5.2, 02:08:04, FastEthernet0/0
D 192.168.10.0/24 [90/2172416] via 10.1.3.2, 02:07:59, Serial0/0/1
[90/2172416] via 10.1.2.2, 02:07:59, Serial0/0/0
D 192.168.20.0/24 [90/2172416] via 10.1.3.2, 02:07:59, Serial0/0/1
[90/2172416] via 10.1.2.2, 02:07:59, Serial0/0/0
D 192.168.30.0/24 [90/2172416] via 10.1.4.2, 02:07:58, Serial0/1/0
D 192.168.40.0/24 [90/2172416] via 10.1.4.2, 02:07:58, Serial0/1/0
Corp#
show ip eigrp interfaces
IP-EIGRP interfaces for process 10
Xmit Queue Mean Pacing Time Multicast Pending
Interface Peers Un/Reliable SRTT Un/Reliable Flow Timer Routes
Vlan 0 0/0 1236 0/10 0 0
Fa0/0 1 0/0 1236 0/10 0 0
Se0/1/0 1 0/0 1236 0/10 0 0
Se0/0/1 1 0/0 1236 0/10 0 0
Se0/0/0 1 0/0 1236 0/10 0 0
Corp#
show ip protocols
Routing Protocol is "eigrp 10 "
Outgoing update filter list for all interfaces is not set
Incoming update filter list for all interfaces is not set
Default networks flagged in outgoing updates
Default networks accepted from incoming updates
Redistributing: eigrp 10
EIGRP-IPv4 Protocol for AS(10)
Metric weight K1=1, K2=0, K3=1, K4=0, K5=0 using K1 bandwidth and K2 delay by default
NSF-aware route hold timer is 240
Router-ID: 10.1.1.1
Topology : 0 (base)
Active Timer: 3 min
Distance: internal 90 external 170
Maximum path: 4
Maximum hopcount 100
Maximum metric variance 1
Automatic Summarization: disabled
Automatic address summarization:
Maximum path: 4
Routing for Networks:
10.0.0.0
Routing Information Sources:
Gateway Distance Last Update
10.1.5.2 90 0
10.1.3.2 90 8936
10.1.4.2 90 9511
10.1.2.2 90 9597
Distance: internal 90 external 170
Routing Protocol is "rip"
Sending updates every 30 seconds, next due in 13 seconds
Invalid after 180 seconds, hold down 180, flushed after 240
Outgoing update filter list for all interfaces is not set
Incoming update filter list for all interfaces is not set
Redistributing: rip
Default version control: send version 2, receive 2
Interface Send Recv Triggered RIP Key-chain
Vlan1 2 2
FastEthernet0/0 2 2
Serial0/0/1 2 2
Serial0/1/0 2 2
Serial0/0/0 2 2
Automatic network summarization is not in effect
Maximum path: 4
Routing for Networks:
10.0.0.0
Passive Interface(s):
Routing Information Sources:
Gateway Distance Last Update
10.1.5.2 120 00:00:05
10.1.3.2 120 00:00:12
10.1.2.2 120 00:00:12
10.1.4.2 120 00:00:17
Distance: (default is 120)
corp#
debug eigrp packet
break into two columns for readability
Observations:
There doesnt appear to be a pattern in the order each router is addressed, except that the TO's and FROM"s are grouped together
The TO messages dont show the destination IP, only the egress local interface
The FROM messages do show the remote IP, as well as the local ingress interface
Corp#
EIGRP: Received HELLO on FastEthernet0/0 nbr 10.1.5.2
AS 10, Flags 0x0, Seq 18/0 idbQ 0/0
hello from R3
Corp#
EIGRP: Received HELLO on Serial0/1/0 nbr 10.1.4.2
AS 10, Flags 0x0, Seq 16/0 idbQ 0/0
hello from R2
Corp#
EIGRP: Received HELLO on Serial0/0/0 nbr 10.1.2.2
AS 10, Flags 0x0, Seq 19/0 idbQ 0/0
hello from R1
------------------------------------------------------------
Corp#
EIGRP: Sending HELLO on Serial0/1/0
AS 10, Flags 0x0, Seq 21/0 idbQ 0/0 iidbQ un/rely 0/0
hello to R2
Corp#
EIGRP: Sending HELLO on FastEthernet0/0
AS 10, Flags 0x0, Seq 21/0 idbQ 0/0 iidbQ un/rely 0/0
hello to R3
Corp#
EIGRP: Sending HELLO on Serial0/0/1
AS 10, Flags 0x0, Seq 21/0 idbQ 0/0 iidbQ un/rely 0/0
hello to R1
Corp#
EIGRP: Sending HELLO on Serial0/0/0
AS 10, Flags 0x0, Seq 21/0 idbQ 0/0 iidbQ un/rely 0/0
hello to R1
Corp#
EIGRP: Sending HELLO on Vlan1
AS 10, Flags 0x0, Seq 21/0 idbQ 0/0 iidbQ un/rely 0/0
hello to switch card (not a router....)
------------------------------------------------------------
Corp#
EIGRP: Received HELLO on Serial0/0/1 nbr 10.1.3.2
AS 10, Flags 0x0, Seq 19/0 idbQ 0/0
hello from R1
Corp#
EIGRP: Received HELLO on FastEthernet0/0 nbr 10.1.5.2
AS 10, Flags 0x0, Seq 18/0 idbQ 0/0
hello from R3
Corp#
EIGRP: Received HELLO on Serial0/0/0 nbr 10.1.2.2
AS 10, Flags 0x0, Seq 19/0 idbQ 0/0
hello from R1
Corp#
EIGRP: Received HELLO on Serial0/1/0 nbr 10.1.4.2
AS 10, Flags 0x0, Seq 16/0 idbQ 0/0
hello from R2
------------------------------------------------------------
Corp#
EIGRP: Sending HELLO on Serial0/1/0
AS 10, Flags 0x0, Seq 21/0 idbQ 0/0 iidbQ un/rely 0/0
hello to R2... no neighbor IP?
Corp#
EIGRP: Sending HELLO on Serial0/0/0
AS 10, Flags 0x0, Seq 21/0 idbQ 0/0 iidbQ un/rely 0/0
hello to R1... no neighbor IP?
Corp#
EIGRP: Sending HELLO on FastEthernet0/0
AS 10, Flags 0x0, Seq 21/0 idbQ 0/0 iidbQ un/rely 0/0
hello to R3... no neighbor IP?
Corp#
EIGRP: Sending HELLO on Serial0/0/1
AS 10, Flags 0x0, Seq 21/0 idbQ 0/0 iidbQ un/rely 0/0
hello to R1
Corp#
EIGRP: Sending HELLO on Vlan1
AS 10, Flags 0x0, Seq 21/0 idbQ 0/0 iidbQ un/rely 0/0
hello to switch card (not a router)
------------------------------------------------------------
OUTPUT CONTINUES IN NEXT COLUMN
Corp#
EIGRP: Received HELLO on Serial0/0/1 nbr 10.1.3.2
AS 10, Flags 0x0, Seq 19/0 idbQ 0/0
hello from R1
Corp#
EIGRP: Received HELLO on FastEthernet0/0 nbr 10.1.5.2
AS 10, Flags 0x0, Seq 18/0 idbQ 0/0
hello from R3
Corp#
EIGRP: Received HELLO on Serial0/0/0 nbr 10.1.2.2
AS 10, Flags 0x0, Seq 19/0 idbQ 0/0
hello from R1
Corp#
EIGRP: Received HELLO on Serial0/1/0 nbr 10.1.4.2
AS 10, Flags 0x0, Seq 16/0 idbQ 0/0
hello from R2
------------------------------------------------------------
Corp#
EIGRP: Sending HELLO on Serial0/1/0
AS 10, Flags 0x0, Seq 21/0 idbQ 0/0 iidbQ un/rely 0/0
hello to R2
Corp#
EIGRP: Sending HELLO on Serial0/0/0
AS 10, Flags 0x0, Seq 21/0 idbQ 0/0 iidbQ un/rely 0/0
hello to R1
Corp#
EIGRP: Sending HELLO on Vlan1
AS 10, Flags 0x0, Seq 21/0 idbQ 0/0 iidbQ un/rely 0/0
hello to Corp switchcard
Corp#
EIGRP: Sending HELLO on Serial0/0/1
AS 10, Flags 0x0, Seq 21/0 idbQ 0/0 iidbQ un/rely 0/0
hello to R1
Corp#
EIGRP: Sending HELLO on FastEthernet0/0
AS 10, Flags 0x0, Seq 21/0 idbQ 0/0 iidbQ un/rely 0/0
hello to R3... no neighbor IP?
------------------------------------------------------------
Corp#
EIGRP: Received HELLO on Serial0/0/1 nbr 10.1.3.2
AS 10, Flags 0x0, Seq 19/0 idbQ 0/0
hello from R1
Corp#
EIGRP: Received HELLO on FastEthernet0/0 nbr 10.1.5.2
AS 10, Flags 0x0, Seq 18/0 idbQ 0/0
hello from R3
Corp#
EIGRP: Received HELLO on Serial0/1/0 nbr 10.1.4.2
AS 10, Flags 0x0, Seq 16/0 idbQ 0/0
hello from R2
Corp#
EIGRP: Received HELLO on Serial0/0/0 nbr 10.1.2.2
AS 10, Flags 0x0, Seq 19/0 idbQ 0/0
hello from R1
------------------------------------------------------------
Corp#
EIGRP: Sending HELLO on Serial0/1/0
AS 10, Flags 0x0, Seq 21/0 idbQ 0/0 iidbQ un/rely 0/0
hello to R2
Corp#
EIGRP: Sending HELLO on Vlan1
AS 10, Flags 0x0, Seq 21/0 idbQ 0/0 iidbQ un/rely 0/0
hello to Corp switchcard
EIGRP: Sending HELLO on Serial0/0/0
AS 10, Flags 0x0, Seq 21/0 idbQ 0/0 iidbQ un/rely 0/0
hello to R1
EIGRP: Sending HELLO on Serial0/0/1
AS 10, Flags 0x0, Seq 21/0 idbQ 0/0 iidbQ un/rely 0/0
hello to R1
Corp#
EIGRP: Sending HELLO on FastEthernet0/0
AS 10, Flags 0x0, Seq 21/0 idbQ 0/0 iidbQ un/rely 0/0
hello to R3
------------------------------------------------------------
Now some videos. To reinforce EIGRP concepts, and lead into OSPF
OSPF - OPEN SHORTEST PATH FIRST
Before enabling OSPF, we'll turn off RIP and EIGRP on all four routers.
Device(config)#
no router eigrp 10
Device(config)#
no router rip
The OSPF configs for the local egress ip address
Corp(config)#
router ospf 132
Corp(config)#
network 10.1.0.0 0.0.255.255 area 0
R1(config)#
router ospf 1
R1(config)#
network 10.1.0.0 0.0.255.255 area 0
R1(config)#
network 192.168.0.0 0.0.255.255 area 0
R2(config)#
router ospf 45678
R2(config)#
network 10.0.0.0 0.0.0.255 area 0
R2(config)#
network 192.168.30.1 0.0.0.0 area 0
R2(config)#
network 192.168.40.1 0.0.0.0 area 0
all 32 bits of the mask are specified for the 192 entries;
these are not network id's, they are HOST id's of the specific interfaces, which are EGRESS interfaces on the router we are configuring
R3(config)#
router ospf 1
R2(config)#
network 10.1.5.2 0.0.0.255 area 0
R2(config)#
network 172.16.10.0 0.0.0.255 area 0
Wildcard Masks
these notes are not intended to be a precise explanation of wlidcard masking, but rather a look into my thought process as I am learning the concept.
resources:
traceroute blog examples
routerjockey blog examples
subnetonline wildcard calculator
Ch 9 Exam Essentials
1. Know EIGRP features
classless (like RipV2 and OSPF)
distance vector
supports IP, IPX, appleTalk, IPV6
supports summaries and discontiguous networks
uses the Diffusing Update Algorithm (DUAL) to maintain route information
uses RTP to communicate with other EIGRP routers
uses the concept of an autonomous system to describe the set of contiguous routers that run the same routing protocol and share routing information
considered CLASSLESS- includes the subnet mask in its route updates
sends traditional distance-vector updates containing info about networks plus the cost of reaching them from the perspective of the advertising router
but not strictly distance-vector. Has link-state characteristics: synchronizes routing tables between neighbors at startup and then sends specific updates only when topology changes.
max hop count of 255 (default is 100)
but hop count is NOT a metric, like in RIP. Hop count is how many routers an EIGRP route update can traverse before being discarded. This limits the size of the AS.
2. Know how to configure EIGRP
the router eigrp [as] command turns EIGRP routing on in the router. Unlike RIPv1, EIGRP uses classless routing. BUT you can still configure as classful.
R1(config)#
router eigrp 10
enters router config mode
R1(config-router)#
network 10.0.0.0
on this router, interfaces that fall within 10.0.0.0 will advertise EIGRP info
3. Know how to verify EIGRP operation
Corp#
show ip
protocols
Corp#
show ip
route
Corp#
show ip
route eigrp
Corp#
show ip
eigrp neighbors
Corp#
show ip
eigrp topology
Corp#
show ip
eigrp interfaces
Corp#
show ip
protocols
info about all active routing protocols
Routing Protocol is "eigrp 10 "
Outgoing update filter list for all interfaces is not set
Incoming update filter list for all interfaces is not set
Default networks flagged in outgoing updates
Default networks accepted from incoming updates
Redistributing: eigrp 10
EIGRP-IPv4 Protocol for AS(10)
Metric weight K1=1, K2=0, K3=1, K4=0, K5=0
NSF-aware route hold timer is 240
Router-ID: 10.1.1.1
Topology : 0 (base)
Active Timer: 3 min
Distance: internal 90 external 170
Maximum path: 4
Maximum hopcount 100
Maximum metric variance 1
Automatic Summarization: disabled
Automatic address summarization:
Maximum path: 4
Routing for Networks:
10.0.0.0
Routing Information Sources:
Gateway Distance Last Update
10.1.2.2 90 200105
10.1.3.2 90 200113
10.1.4.2 90 254351
10.1.5.2 90 303742
Distance: internal 90 external 170
Corp#
show ip
protocols
(continued)
Routing Protocol is "rip"
Sending updates every 30 seconds, next due in 6 seconds
Invalid after 180 seconds, hold down 180, flushed after 240
Outgoing update filter list for all interfaces is not set
Incoming update filter list for all interfaces is not set
Redistributing: rip
Default version control: send version 2, receive 2
Interface Send Recv Triggered RIP Key-chain
Vlan1 2 2
FastEthernet0/0 2 2
Serial0/1/0 2 2
Serial0/0/1 2 2
Serial0/0/0 2 2
Automatic network summarization is not in effect
Maximum path: 4
Routing for Networks:
10.0.0.0
Passive Interface(s):
Routing Information Sources:
Gateway Distance Last Update
10.1.5.2 120 00:00:15
10.1.3.2 120 00:00:01
10.1.2.2 120 00:00:01
10.1.4.2 120 00:00:17
Distance: (default is 120)
Corp#
show ip
route
entire routing table
Codes: L - local, C - connected, S - static, R - RIP, M - mobile, B - BGP
D - EIGRP, EX - EIGRP external, O - OSPF, IA - OSPF inter area
N1 - OSPF NSSA external type 1, N2 - OSPF NSSA external type 2
E1 - OSPF external type 1, E2 - OSPF external type 2, E - EGP
i - IS-IS, L1 - IS-IS level-1, L2 - IS-IS level-2, ia - IS-IS inter area
* - candidate default, U - per-user static route, o - ODR
P - periodic downloaded static route
Gateway of last resort is not set
10.0.0.0/8 is variably subnetted, 10 subnets, 2 masks
C 10.1.1.0/24 is directly connected, Vlan1
L 10.1.1.1/32 is directly connected, Vlan1
C 10.1.2.0/24 is directly connected, Serial0/0/0
L 10.1.2.1/32 is directly connected, Serial0/0/0
C 10.1.3.0/24 is directly connected, Serial0/0/1
L 10.1.3.1/32 is directly connected, Serial0/0/1
C 10.1.4.0/24 is directly connected, Serial0/1/0
L 10.1.4.1/32 is directly connected, Serial0/1/0
C 10.1.5.0/24 is directly connected, FastEthernet0/0
L 10.1.5.1/32 is directly connected, FastEthernet0/0
172.16.0.0/16 is variably subnetted, 2 subnets, 2 masks
R 172.16.0.0/16 [120/1] via 10.1.5.2, 00:00:14, FastEthernet0/0
D 172.16.10.0/24 [90/28160] via 10.1.5.2, 00:07:23, FastEthernet0/0
D 192.168.10.0/24 [90/2172416] via 10.1.3.2, 00:09:13, Serial0/0/1
[90/2172416] via 10.1.2.2, 00:09:13, Serial0/0/0
D 192.168.20.0/24 [90/2172416] via 10.1.3.2, 00:09:13, Serial0/0/1
[90/2172416] via 10.1.2.2, 00:09:13, Serial0/0/0
D 192.168.30.0/24 [90/2172416] via 10.1.4.2, 00:08:59, Serial0/1/0
D 192.168.40.0/24 [90/2172416] via 10.1.4.2, 00:08:59, Serial0/1/0
Shows the entire routing table
Corp#
show ip
eigrp toplogy
all nets the Corp router can see, including on the other side of other routers
IP-EIGRP Topology Table for AS 10/ID(10.1.5.1)
Codes: P - Passive, A - Active, U - Update, Q - Query, R - Reply,
r - Reply status
directly connected via local egress interface
P 10.1.1.0/24, 1 successors, FD is 25625600
via Connected, Vlan1
P 10.1.2.0/24, 1 successors, FD is 2169856
via Connected, Serial0/0/0
P 10.1.3.0/24, 1 successors, FD is 2169856
via Connected, Serial0/0/1
P 10.1.4.0/24, 1 successors, FD is 2169856
via Connected, Serial0/1/0
P 10.1.5.0/24, 1 successors, FD is 28160
via Connected, FastEthernet0/0
remotely connected via remote ingress ip address
P 172.16.10.0/24, 1 successors, FD is 28160
via 10.1.5.2 (28160/25600), FastEthernet0/0
P 192.168.10.0/24, 2 successors, FD is 2172416
via 10.1.3.2 (2172416/28160), Serial0/0/1
via 10.1.2.2 (2172416/28160), Serial0/0/0
P 192.168.20.0/24, 2 successors, FD is 2172416
via 10.1.3.2 (2172416/28160), Serial0/0/1
via 10.1.2.2 (2172416/28160), Serial0/0/0
P 192.168.30.0/24, 1 successors, FD is 2172416
via 10.1.4.2 (2172416/28160), Serial0/1/0
P 192.168.40.0/24, 1 successors, FD is 2172416
via 10.1.4.2 (2172416/28160), Serial0/1/0
Corp#
show ip
eigrp interfaces
local interfaces on Corp, with peer data, 5 total, including VLAN1 (0 peers, no router on this network)
IP-EIGRP interfaces for process 10
Xmit Queue Mean Pacing Time Multicast Pending
Interface Peers Un/Reliable SRTT Un/Reliable Flow Timer Routes
Vlan 0 0/0 1236 0/10 0 0
Fa0/0 1 0/0 1236 0/10 0 0
Se0/0/1 1 0/0 1236 0/10 0 0
Se0/1/0 1 0/0 1236 0/10 0 0
Se0/0/0 1 0/0 1236 0/10 0 0
Corp#
show ip
eigrp neighbors
remote interfaces on the 4 neighboring routers
IP-EIGRP neighbors for process 10
H Address Interface Hold Uptime SRTT RTO Q Seq
(sec) (ms) Cnt Num
0 10.1.2.2 Se0/0/0 14 00:54:33 40 1000 0 58
1 10.1.3.2 Se0/0/1 10 00:54:33 40 1000 0 57
2 10.1.4.2 Se0/1/0 14 00:53:38 40 1000 0 51
3 10.1.5.2 Fa0/0 11 00:52:49 40 1000 0 33
4. Compare OSPF and RIPv1
RIPv1 is distance-vector and supports only classful routing. No VLSM
OSPF is link-state and supports VLSM and classless routing
5. Know how OSPF routers become neighboars and/or adjacent
they become neighbors when they see eachother's hello packets.
area id must match, links must be on the same subnet, hello/dead timers must be the same.
OSPF only shares routes with neigbors who have also established adjacencies. NOT ALL NEIGHBORS become adjacent.
When an OSPF router first receives a hello packet, it verifies that the data in some fields matches its own locally configured information.
Should any of the checked data be different, the hello packet is discarded and not processed. The data fields verified are the Area ID,
Authentication, Network Mask (on broadcast networks), Hello Interval, Router Dead Interval, and Options fields. If this information doesn’t match,
then neighborship is stuck in the down stage.
packetpushers.net
6. Be able to configure single-area OSPF
two commands:
router ospf [process id]
network x.x.x.x y.y.y.y area z
7. Be able to verify the operation of OSPF
Corp#
show ip
protocols
Corp#
show ip
route
Corp#
show ip
ospf
Corp#
show ip
ospf database
Corp#
show ip
ospf interface
Corp#
show ip
ospf neighbor
IOS 15.1
Corp#
show ip
protocols
Routing Protocol is "ospf 132"
Outgoing update filter list for all interfaces is not set
Incoming update filter list for all interfaces is not set
Router ID 10.1.5.1
Number of areas in this router is 1. 1 normal 0 stub 0 nssa
Maximum path: 4
Routing for Networks:
10.1.0.0 0.0.255.255 area 0
Routing Information Sources:
Gateway Distance Last Update
10.1.5.1 110 00:08:51
172.16.10.1 110 00:08:51
192.168.20.1 110 00:12:53
192.168.40.1 110 00:09:35
Distance: (default is 110)
IOS 15.1
Corp#
show ip
route
10.0.0.0/8 is variably subnetted, 10 subnets, 2 masks
C 10.1.1.0/24 is directly connected, Vlan1
L 10.1.1.1/32 is directly connected, Vlan1
C 10.1.2.0/24 is directly connected, Serial0/0/0
L 10.1.2.1/32 is directly connected, Serial0/0/0
C 10.1.3.0/24 is directly connected, Serial0/0/1
L 10.1.3.1/32 is directly connected, Serial0/0/1
C 10.1.4.0/24 is directly connected, Serial0/1/0
L 10.1.4.1/32 is directly connected, Serial0/1/0
C 10.1.5.0/24 is directly connected, FastEthernet0/0
L 10.1.5.1/32 is directly connected, FastEthernet0/0
172.16.0.0/24 is subnetted, 1 subnets
O 172.16.10.0/24 [110/10] via 10.1.5.2, 00:09:09, FastEthernet0/0
O 192.168.10.0/24 [110/65] via 10.1.2.2, 00:13:11, Serial0/0/0
O 192.168.20.0/24 [110/65] via 10.1.2.2, 00:13:01, Serial0/0/0
O 192.168.30.0/24 [110/65] via 10.1.4.2, 00:09:54, Serial0/1/0
O 192.168.40.0/24 [110/65] via 10.1.4.2, 00:09:54, Serial0/1/0
IOS 15.1
Corp#
show ip
ospf
Routing Process "ospf 132" with ID 10.1.5.1
Supports only single TOS(TOS0) routes
Supports opaque LSA
SPF schedule delay 5 secs, Hold time between two SPFs 10 secs
Minimum LSA interval 5 secs. Minimum LSA arrival 1 secs
Number of external LSA 0. Checksum Sum 0x000000
Number of opaque AS LSA 0. Checksum Sum 0x000000
Number of DCbitless external and opaque AS LSA 0
Number of DoNotAge external and opaque AS LSA 0
Number of areas in this router is 1. 1 normal 0 stub 0 nssa
External flood list length 0
Area BACKBONE(0)
Number of interfaces in this area is 5
Area has no authentication
SPF algorithm executed 7 times
Area ranges are
Number of LSA 5. Checksum Sum 0x034486
Number of opaque link LSA 0. Checksum Sum 0x000000
Number of DCbitless LSA 0
Number of indication LSA 0
Number of DoNotAge LSA 0
Flood list length 0
IOS 15.1
Corp#
show ip
ospf database
OSPF Router with ID (10.1.5.1) (Process ID 132)
Router Link States (Area 0)
Link ID ADV Router Age Seq# Checksum Link count
192.168.20.1 192.168.20.1 854 0x80000006 0x00ae08 6
192.168.40.1 192.168.40.1 656 0x80000004 0x006bc6 4
10.1.5.1 10.1.5.1 612 0x8000000f 0x00ab77 8
172.16.10.1 172.16.10.1 612 0x80000003 0x00b30d 2
Net Link States (Area 0)
Link ID ADV Router Age Seq# Checksum
10.1.5.1 10.1.5.1 612 0x80000001 0x00cc34
ADV Router aka RID/Router ID, the highest IP address on the router
we are seeing three connected routers + our own router (Corp at 10.1.5.1)
IOS 15.1
Corp#
show ip
ospf interface
Vlan1 is up, line protocol is up
Internet address is 10.1.1.1/24, Area 0
Process ID 132, Router ID 10.1.5.1, Network Type BROADCAST, Cost: 1
Transmit Delay is 1 sec, State DR, Priority 1
Designated Router (ID) 10.1.5.1, Interface address 10.1.1.1
No backup designated router on this network
Timer intervals configured, Hello 10, Dead 40, Wait 40, Retransmit 5
Hello due in 00:00:08
Index 1/1, flood queue length 0
Next 0x0(0)/0x0(0)
Last flood scan length is 1, maximum is 1
Last flood scan time is 0 msec, maximum is 0 msec
Neighbor Count is 0, Adjacent neighbor count is 0
Suppress hello for 0 neighbor(s)
FastEthernet0/0 is up, line protocol is up
Internet address is 10.1.5.1/24, Area 0
Process ID 132, Router ID 10.1.5.1, Network Type BROADCAST, Cost: 1
Transmit Delay is 1 sec, State DR, Priority 1
Designated Router (ID) 10.1.5.1, Interface address 10.1.5.1
Backup Designated Router (ID) 172.16.10.1, Interface address 10.1.5.2
Timer intervals configured, Hello 10, Dead 40, Wait 40, Retransmit 5
Hello due in 00:00:07
Index 2/2, flood queue length 0
Next 0x0(0)/0x0(0)
Last flood scan length is 1, maximum is 1
Last flood scan time is 0 msec, maximum is 0 msec
Neighbor Count is 1, Adjacent neighbor count is 1
Adjacent with neighbor 172.16.10.1 (Backup Designated Router)
Suppress hello for 0 neighbor(s)
Serial0/0/1 is up, line protocol is up
Internet address is 10.1.3.1/24, Area 0
Process ID 132, Router ID 10.1.5.1, Network Type POINT-TO-POINT, Cost: 64
Transmit Delay is 1 sec, State POINT-TO-POINT,
Timer intervals configured, Hello 10, Dead 40, Wait 40, Retransmit 5
Hello due in 00:00:07
Index 3/3, flood queue length 0
Next 0x0(0)/0x0(0)
Last flood scan length is 1, maximum is 1
Last flood scan time is 0 msec, maximum is 0 msec
Neighbor Count is 1 , Adjacent neighbor count is 1
Adjacent with neighbor 192.168.20.1
Suppress hello for 0 neighbor(s)
Serial0/1/0 is up, line protocol is up
Internet address is 10.1.4.1/24, Area 0
Process ID 132, Router ID 10.1.5.1, Network Type POINT-TO-POINT, Cost: 64
Transmit Delay is 1 sec, State POINT-TO-POINT,
Timer intervals configured, Hello 10, Dead 40, Wait 40, Retransmit 5
Hello due in 00:00:07
Index 4/4, flood queue length 0
Next 0x0(0)/0x0(0)
Last flood scan length is 1, maximum is 1
Last flood scan time is 0 msec, maximum is 0 msec
Neighbor Count is 1 , Adjacent neighbor count is 1
Adjacent with neighbor 192.168.40.1
Suppress hello for 0 neighbor(s)
Serial0/0/0 is up, line protocol is up
Internet address is 10.1.2.1/24, Area 0
Process ID 132, Router ID 10.1.5.1, Network Type POINT-TO-POINT, Cost: 64
Transmit Delay is 1 sec, State POINT-TO-POINT,
Timer intervals configured, Hello 10, Dead 40, Wait 40, Retransmit 5
Hello due in 00:00:07
Index 5/5, flood queue length 0
Next 0x0(0)/0x0(0)
Last flood scan length is 1, maximum is 1
Last flood scan time is 0 msec, maximum is 0 msec
Neighbor Count is 1 , Adjacent neighbor count is 1
Adjacent with neighbor 192.168.20.1
Suppress hello for 0 neighbor(s)
IOS 15.1
Corp#
show ip
ospf neighbor
Neighbor ID Pri State Dead Time Address Interface
192.168.20.1 0 FULL/ - 00:00:31 10.1.3.2 Serial0/0/1
192.168.40.1 0 FULL/ - 00:00:33 10.1.4.2 Serial0/1/0
192.168.20.1 0 FULL/ - 00:00:31 10.1.2.2 Serial0/0/0
172.16.10.1 1 FULL/BDR 00:00:32 10.1.5.2 FastEthernet0/0
Flashcards
Chapter 9 Written Lab 9.0
1. What four routed protocols are supported by EIGRP?
IPX, IPv4, IPv6, AppleTalk
2. When is redistribution required for EIGRP?
when there are multiple autonomous systems
redistribution is required when more than one EIGRP session or process is running and they are identified with different ASNs.
redistribution shares toplogy information between EIGRP sessions
3. What command would be used to enable EIGRP with an autonmous system number of 300?
router eigrp 300
4. What command will tell EIGRP that it is connected to network 172.10.0.0?
network 172.10.0.0
5. What type of EIGRP interface will neither send nor receive Hello packets?
passive-interface s0/0
6. Write the command that will enable OSPF process 101 on a router
router ospf 101
7. Write the command that will display details of all OSFP routing processes enabled on a router
show ip ospf
8. Write the command that will display interface-specific OSPF information
show ip ospf interface
9. Write the command that will display all OSPF neighbors
show ip ospf neighbor
10. Write the command that will display all different OSPF route types that are currently known by the router
show ip route ospf
Chapter 9 Hands-On Labs
Build the network and configure interfaces
LabA(config)#
int f0/0
LabA(config-if)#
ip addr 172.16.10.1 255.255.255.0
LabA(config-if)#
no shut
LabB(config)#
int f0/0
LabB(config-if)#
ip addr 172.16.10.2 255.255.255.0
LabB(config-if)#
no shut
LabB(config-if)#
int s0/0/0
LabB(config-if)#
ip addr 172.16.20.1 255.255.255.0
LabB(config-if)#
no shut
LabC(config)#
int f0/0
LabC(config-if)#
ip addr 172.16.30.1 255.255.255.0
LabC(config-if)#
no shut
LabC(config-if)#
int s0/0/0
LabC(config-if)#
ip addr 172.16.20.2 255.255.255.0
LabC(config-if)#
no shut
LabC(config-if)#
int s0/0/1
LabC(config-if)#
ip addr 172.16.40.1 255.255.255.0
LabC(config-if)#
no shut
LabD(config)#
int s0/0/0
LabD(config-if)#
ip addr 172.16.40.2 255.255.255.0
LabD(config-if)#
no shut
LabD(config-if)#
int f0/0
LabD(config-if)#
ip addr 172.16.50.1 255.255.255.0
LabD(config-if)#
no shut
9.1 - Configure and Verfiy EIGRP
configure EIGRP on all 4 routers and observe results
LabA
LabA(config)#
router eigrp 100
LabA(config-router)#
net 172.16.0.0
[no output]
LabA#
show ip eigrp neighbors
IP-EIGRP neighbors for process 100
LabA#
show ip eigrp topology
IP-EIGRP Topology Table for AS 100/ID(172.16.10.1)
Codes: P - Passive, A - Active, U - Update, Q - Query, R - Reply,
r - Reply status
P 172.16.10.0/24, 1 successors, FD is 28160
via Connected, FastEthernet0/0
LabA#
show ip eigrp interfaces
IP-EIGRP interfaces for process 100
Xmit Queue Mean Pacing Time Multicast Pending
Interface Peers Un/Reliable SRTT Un/Reliable Flow Timer Routes
Fa0/0 0 0/0 1236 0/10 0 0
no neighbors at this point since EIGRP is only active on this router. One successor AKA route, which is the connection out of this router.
But note that we have no information about what's on the other side of that link
LabB
LabB(config)#
router eigrp 100
LabB(config-router)#
net 172.16.0.0
%DUAL-5-NBRCHANGE: IP-EIGRP 100:
Neighbor 172.16.10.1 (FastEthernet0/0) is up: new adjacency
LabB#
show ip eigrp neighbors
IP-EIGRP neighbors for process 100
H Address Interface Hold Uptime SRTT RTO Q Seq
(sec) (ms) Cnt Num
0 172.16.10.1 Fa0/0 12 00:00:14 40 1000 0 1
LabB#
show ip eigrp topology
IP-EIGRP Topology Table for AS 100/ID(172.16.20.1)
Codes: P - Passive, A - Active, U - Update, Q - Query, R - Reply,
r - Reply status
P 172.16.10.0/24, 1 successors, FD is 28160
via Connected, FastEthernet0/0
P 172.16.20.0/24, 1 successors, FD is 2169856
via Connected, Serial0/0/0
LabB#
show ip eigrp interfaces
IP-EIGRP interfaces for process 100
Xmit Queue Mean Pacing Time Multicast Pending
Interface Peers Un/Reliable SRTT Un/Reliable Flow Timer Routes
Fa0/0 1 0/0 1236 0/10 0 0
Se0/0/0 0 0/0 1236 0/10 0 0
We can see a neighbor at .1
We now have two paths out of this router. Left to neighbor. Exit at right is available as successor(route), but again we have no info about
what is on the other side, since that router has no EIGRP yet (s0/0/0 has no peers, but is an EIGRP interface)
LabC
LabC(config)#
router eigrp 100
LabC(config-router)#
net 172.16.0.0
%DUAL-5-NBRCHANGE: IP-EIGRP 100:
Neighbor 172.16.20.1 (Serial0/0/0) is up: new adjacency
LabC#
show ip eigrp neighbors
IP-EIGRP neighbors for process 100
H Address Interface Hold Uptime SRTT RTO Q Seq
(sec) (ms) Cnt Num
0 172.16.20.1 Se0/0/0 12 00:00:25 40 1000 0 8
LabC#
show ip eigrp toplogy
IP-EIGRP Topology Table for AS 100/ID(172.16.40.1)
Codes: P - Passive, A - Active, U - Update, Q - Query, R - Reply,
r - Reply status
P 172.16.10.0/24, 1 successors, FD is 2172416
via 172.16.20.1 (2172416/28160), Serial0/0/0
P 172.16.20.0/24, 1 successors, FD is 2169856
via Connected, Serial0/0/0
P 172.16.30.0/24, 1 successors, FD is 28160
via Connected, FastEthernet0/0
P 172.16.40.0/24, 1 successors, FD is 2169856
via Connected, Serial0/0/1
LabC#
show ip eigrp interfaces
IP-EIGRP interfaces for process 100
Xmit Queue Mean Pacing Time Multicast Pending
Interface Peers Un/Reliable SRTT Un/Reliable Flow Timer Routes
Fa0/0 0 0/0 1236 0/10 0 0
Se0/0/0 1 0/0 1236 0/10 0 0
Se0/0/1 0 0/0 1236 0/10 0 0
.1 router B interface is now a neighbor.
LabC topology shows the 3 direct connected networks AND the network on the other side of LabB since LabB is our EIGRP neighbor
3 eigrp interfaces:
Fa0/0 is ours at LabC- no peers bc there is no eigrp router on the other end
s0/0/0 is our interface out left to LabB which is an EIGRP peer
s0/0/1 is our interface out right which does not see an EIGRP peer but does put that net 172.16.40.0 in our topology
LabD
LabD(config)#
router eigrp 100
LabD(config-router)#
net 172.16.0.0
%DUAL-5-NBRCHANGE: IP-EIGRP 100:
Neighbor 172.16.40.1 (Serial0/0/0) is up: new adjacency
LabD#
show ip eigrp neighbors
IP-EIGRP neighbors for process 100
H Address Interface Hold Uptime SRTT RTO Q Seq
(sec) (ms) Cnt Num
0 172.16.40.1 Se0/0/0 11 00:00:14 40 1000 0 6
LabD#
show ip eigrp topology
IP-EIGRP Topology Table for AS 100/ID(172.16.50.1)
Codes: P - Passive, A - Active, U - Update, Q - Query, R - Reply,
r - Reply status
P 172.16.10.0/24, 1 successors, FD is 2684416
via 172.16.40.1 (2684416/2172416), Serial0/0/0
P 172.16.20.0/24, 1 successors, FD is 2681856
via 172.16.40.1 (2681856/2169856), Serial0/0/0
P 172.16.30.0/24, 1 successors, FD is 2172416
via 172.16.40.1 (2172416/28160), Serial0/0/0
P 172.16.40.0/24, 1 successors, FD is 2169856
via Connected, Serial0/0/0
P 172.16.50.0/24, 1 successors, FD is 28160
via Connected, FastEthernet0/0
LabD#
show ip eigrp interfaces
IP-EIGRP interfaces for process 100
Xmit Queue Mean Pacing Time Multicast Pending
Interface Peers Un/Reliable SRTT Un/Reliable Flow Timer Routes
Fa0/0 0 0/0 1236 0/10 0 0
Se0/0/0 1 0/0 1236 0/10 0 0
LabC to our left is now a neighbor at 172.16.40.1
toplogy shows a route out to the right (no router on that end)
a route to the left to LabC .40.0
the .10.0, .20.0, and .30.0 networks via info from LabC
2 eigrp interfaces-
fa0/0 out to the right
s0/0/0 out left to LabC
Time to remove EIGRP from all four routers to prepare for the OSPF lab next,
since EIGRP has a lower AD than OSPF
LabA(config)#
no router eigrp 100
LabB(config)#
no router eigrp 100
LabC(config)#
no router eigrp 100
LabD(config)#
no router eigrp 100
9.2 - Enabling the OSPF Process
9.3 - Configuring OSPF Interfaces
9.4 - Verifying OSPF Operation
LabA
LabA(config)#
router ospf 100
LabA(config-router)#
net 172.16.10.1 0.0.0.0 area 0
[no output]
LabA#
show ip ospf neighbor
[no output]
LabA#
show ip ospf database
OSPF Router with ID (172.16.10.1) (Process ID 100)
Router Link States (Area 0)
Link ID ADV Router Age Seq# Checksum Link count
172.16.10.1 172.16.10.1 44 0x80000001 0x00b24b 1
LabA#
show ip ospf interface
FastEthernet0/0 is up, line protocol is up
Internet address is 172.16.10.1/24, Area 0
Process ID 100, Router ID 172.16.10.1, Network Type BROADCAST, Cost: 1
Transmit Delay is 1 sec, State DR, Priority 1
Designated Router (ID) 172.16.10.1, Interface address 172.16.10.1
No backup designated router on this network
Timer intervals configured, Hello 10, Dead 40, Wait 40, Retransmit 5
Hello due in 00:00:08
Index 1/1, flood queue length 0
Next 0x0(0)/0x0(0)
Last flood scan length is 1, maximum is 1
Last flood scan time is 0 msec, maximum is 0 msec
Neighbor Count is 0, Adjacent neighbor count is 0
Suppress hello for 0 neighbor(s)
we're including this router's interface 172.16.10.1 in our ospf area 0
fa0/0 now registers as an ospf interface
the ospf database includes data about this link only.... LabA is counting itself(10.1) as ADVERTISTING router?
the designated router is .1 LabA
LabB
LabB(config)#
router ospf 101
LabB(config-router)#
net 172.16.10.2 0.0.0.0 area 0
LabB(config-router)#
net 172.16.20.1 0.0.0.0 area 0
01:26:36: %OSPF-5-ADJCHG: Process 101, Nbr 172.16.10.1
on FastEthernet0/0 from LOADING to FULL, Loading Done
LabB#
show ip ospf neighbor
Neighbor ID Pri State Dead Time Address Interface
172.16.10.1 1 FULL/DR 00:00:33 172.16.10.1
LabB#
show ip ospf database
OSPF Router with ID (172.16.20.1) (Process ID 101)
Router Link States (Area 0)
Link ID ADV Router Age Seq# Checksum Link count
172.16.10.1 172.16.10.1 145 0x80000002 0x0067cd 1
172.16.20.1 172.16.20.1 32 0x80000003 0x006e8f 2
Net Link States (Area 0)
Link ID ADV Router Age Seq# Checksum
172.16.10.1 172.16.10.1 145 0x80000001 0x00953d
LabB#
show ip ospf interface
FastEthernet0/0 is up, line protocol is up
Internet address is 172.16.10.2/24, Area 0
Process ID 101, Router ID 172.16.20.1, Network Type BROADCAST, Cost: 1
Transmit Delay is 1 sec, State BDR, Priority 1
Designated Router (ID) 172.16.10.1, Interface address 172.16.10.1
Backup Designated Router (ID) 172.16.20.1, Interface address 172.16.10.2
Timer intervals configured, Hello 10, Dead 40, Wait 40, Retransmit 5
Hello due in 00:00:03
Index 1/1, flood queue length 0
Next 0x0(0)/0x0(0)
Last flood scan length is 1, maximum is 1
Last flood scan time is 0 msec, maximum is 0 msec
Neighbor Count is 1, Adjacent neighbor count is 1
Adjacent with neighbor 172.16.10.1 (Designated Router)
Suppress hello for 0 neighbor(s)
Serial0/0/0 is up, line protocol is up
Internet address is 172.16.20.1/24, Area 0
Process ID 101, Router ID 172.16.20.1, Network Type POINT-TO-POINT, Cost: 64
Transmit Delay is 1 sec, State POINT-TO-POINT,
Timer intervals configured, Hello 10, Dead 40, Wait 40, Retransmit 5
Hello due in 00:00:04
Index 2/2, flood queue length 0
Next 0x0(0)/0x0(0)
Last flood scan length is 1, maximum is 1
Last flood scan time is 0 msec, maximum is 0 msec
Suppress hello for 0 neighbor(s)
We've include the two interfaces on this router in the OSPF area
and can now see Router A's interface 10.1 to the left as a neighbor in the area
the "OSPF Database" now shows two links 20.1(local) and 10.1(neighbor) as 'router link states'.
"ADV Router" means advertising router for the two links. The link address is used as the advertising router.
database shows "Net Link States" category with one entry- 172.16.10.1 which is the address of neighbor router to our left
we have two local OSPF interfaces- f0/0 and s0/0/0
LabC
LabC(config)#
router ospf 102
LabC(config-router)#
net 172.16.20.2 0.0.0.0 area 0
LabC(config-router)#
net 172.16.30.1 0.0.0.0 area 0
LabC(config-router)#
net 172.16.40.1 0.0.0.0 area 0
01:33:54: %OSPF-5-ADJCHG: Process 102, Nbr 172.16.20.1
on Serial0/0/0 from LOADING to FULL, Loading Done
LabC#
show ip ospf neighbor
Neighbor ID Pri State Dead Time Address Interface
172.16.20.1 0 FULL/ - 00:00:30 172.16.20.1 Serial0/0/0
LabC#
show ip ospf database
OSPF Router with ID (172.16.40.1) (Process ID 102)
Router Link States (Area 0)
Link ID ADV Router Age Seq# Checksum Link count
172.16.10.1 172.16.10.1 542 0x80000002 0x0067cd 1
172.16.20.1 172.16.20.1 90 0x80000004 0x00a551 3
172.16.40.1 172.16.40.1 37 0x80000004 0x00e47c 4
Net Link States (Area 0)
Link ID ADV Router Age Seq# Checksum
172.16.10.1 172.16.10.1 542 0x80000001 0x00953d
LabC#
show ip ospf interface
Serial0/0/0 is up, line protocol is up
Internet address is 172.16.20.2/24, Area 0
Process ID 102, Router ID 172.16.40.1, Network Type POINT-TO-POINT, Cost: 64
Transmit Delay is 1 sec, State POINT-TO-POINT,
Timer intervals configured, Hello 10, Dead 40, Wait 40, Retransmit 5
Hello due in 00:00:01
Index 1/1, flood queue length 0
Next 0x0(0)/0x0(0)
Last flood scan length is 1, maximum is 1
Last flood scan time is 0 msec, maximum is 0 msec
Neighbor Count is 1 , Adjacent neighbor count is 1
Adjacent with neighbor 172.16.20.1
Suppress hello for 0 neighbor(s)
FastEthernet0/0 is up, line protocol is up
Internet address is 172.16.30.1/24, Area 0
Process ID 102, Router ID 172.16.40.1, Network Type BROADCAST, Cost: 1
Transmit Delay is 1 sec, State DR, Priority 1
Designated Router (ID) 172.16.40.1, Interface address 172.16.30.1
No backup designated router on this network
Timer intervals configured, Hello 10, Dead 40, Wait 40, Retransmit 5
Hello due in 00:00:02
Index 2/2, flood queue length 0
Next 0x0(0)/0x0(0)
Last flood scan length is 1, maximum is 1
Last flood scan time is 0 msec, maximum is 0 msec
Neighbor Count is 0, Adjacent neighbor count is 0
Suppress hello for 0 neighbor(s)
Serial0/0/1 is up, line protocol is up
Internet address is 172.16.40.1/24, Area 0
Process ID 102, Router ID 172.16.40.1, Network Type POINT-TO-POINT, Cost: 64
Transmit Delay is 1 sec, State POINT-TO-POINT,
Timer intervals configured, Hello 10, Dead 40, Wait 40, Retransmit 5
Hello due in 00:00:08
Index 3/3, flood queue length 0
Next 0x0(0)/0x0(0)
Last flood scan length is 1, maximum is 1
Last flood scan time is 0 msec, maximum is 0 msec
Suppress hello for 0 neighbor(s)
we include the three nets conneted to labC in the area.. 20.0, 30.0, and 40.0
link to our left, 20.1 is visible as "Neighbor"
OSPF Database-
Router Link States are
10.1(Router A)
20.1(Router B)
40.1(Router C)(This router)
Net Link States
10.1(Router A)... why does only Router A show here?
Reference- router link state vs net link state
Router Link States are type 1 LSAs. It lists all the routers in the area and the number of interfaces. 40.1 has 4 interfaces
Net Link States are the multi-access networks (Type 2 LSAs). The ADV (advertising router) is the DR.
LabD
LabD(config)#
router ospf 103
LabD(config-router)#
net 172.16.40.2 0.0.0.0 area 0
LabD(config-router)#
net 172.16.50.1 0.0.0.0 area 0
01:37:11: %OSPF-5-ADJCHG: Process 103, Nbr 172.16.40.1
on Serial0/0/0 from LOADING to FULL, Loading Done
LabD#
show ip ospf neighbor
Neighbor ID Pri State Dead Time Address Interface
172.16.40.1 0 FULL/ - 00:00:32 172.16.40.1 Serial0/0/0
LabD#
show ip ospf database
OSPF Router with ID (172.16.50.1) (Process ID 103)
Router Link States (Area 0)
Link ID ADV Router Age Seq# Checksum Link count
172.16.10.1 172.16.10.1 785 0x80000002 0x0067cd 1
172.16.20.1 172.16.20.1 333 0x80000004 0x00a551 3
172.16.40.1 172.16.40.1 111 0x80000005 0x00013b 5
172.16.50.1 172.16.50.1 53 0x80000003 0x001023 3
Net Link States (Area 0)
Link ID ADV Router Age Seq# Checksum
172.16.10.1 172.16.10.1 785 0x80000001 0x00953d
LabD#
show ip ospf interface
Serial0/0/0 is up, line protocol is up
Internet address is 172.16.40.2/24, Area 0
Process ID 103, Router ID 172.16.50.1, Network Type POINT-TO-POINT, Cost: 64
Transmit Delay is 1 sec, State POINT-TO-POINT,
Timer intervals configured, Hello 10, Dead 40, Wait 40, Retransmit 5
Hello due in 00:00:01
Index 1/1, flood queue length 0
Next 0x0(0)/0x0(0)
Last flood scan length is 1, maximum is 1
Last flood scan time is 0 msec, maximum is 0 msec
Neighbor Count is 1 , Adjacent neighbor count is 1
Adjacent with neighbor 172.16.40.1
Suppress hello for 0 neighbor(s)
FastEthernet0/0 is up, line protocol is up
Internet address is 172.16.50.1/24, Area 0
Process ID 103, Router ID 172.16.50.1, Network Type BROADCAST, Cost: 1
Transmit Delay is 1 sec, State WAITING, Priority 1
No designated router on this network
No backup designated router on this network
Timer intervals configured, Hello 10, Dead 40, Wait 40, Retransmit 5
Hello due in 00:00:04
Index 2/2, flood queue length 0
Next 0x0(0)/0x0(0)
Last flood scan length is 1, maximum is 1
Last flood scan time is 0 msec, maximum is 0 msec
Neighbor Count is 0, Adjacent neighbor count is 0
Suppress hello for 0 neighbor(s)
observations
the OSPF databases now match across all 4 routers.
NOTE that this is a database of routers, identified by
router ID. It is not a topology that lists routers AND routes,
like in the "equivalent" eigrp command.show eigrp topology
----------------------------------------------------------------------------------
PAUSE- a tale of a misconfigured network
After a 9 month hiatus, I am reviewing this book and have made it back to Chapter 9. I'm studing this webpage, working thorough the OSPF configurations
described above, and I get stuck on the concept of "link count" under "Router Link States" found in the output of show ip ospf database
The structure of the notes above is helpful, because I was tracking the state of each router BEFORE i made changes to the subsquent router. But just to be sure,
today I decided to recreate the topology, then configure each router one at a time, noting the results as I went.
And I ran into some problems.
Here is the original topology:
And today's recreated toplogy:
After replicating the toplogy and programming the IP addresses on each router, I started on configurations, just like before:
LabA
LabA(config)#
router ospf 100
LabA(config-router)#
net 172.16.10.1 0.0.0.0 area 0
[no output]
LabA#
show ip ospf neighbor
[no output]
LabA#
show ip ospf database
OSPF Router with ID (172.16.10.1) (Process ID 100)
Router Link States (Area 0)
Link ID ADV Router Age Seq# Checksum Link count
172.16.10.1 172.16.10.1 44 0x80000001 0x00b24b 1
LabA#
show ip ospf interface
FastEthernet0/0 is up, line protocol is up
Internet address is 172.16.10.1/24, Area 0
Process ID 100, Router ID 172.16.10.1, Network Type BROADCAST, Cost: 1
Transmit Delay is 1 sec, State DR, Priority 1
Designated Router (ID) 172.16.10.1, Interface address 172.16.10.1
No backup designated router on this network
Timer intervals configured, Hello 10, Dead 40, Wait 40, Retransmit 5
Hello due in 00:00:08
Index 1/1, flood queue length 0
Next 0x0(0)/0x0(0)
Last flood scan length is 1, maximum is 1
Last flood scan time is 0 msec, maximum is 0 msec
Neighbor Count is 0, Adjacent neighbor count is 0
Suppress hello for 0 neighbor(s)
good so far.... On to LabB router
LabB
LabB(config)#
router ospf 101
LabB(config-router)#
net 172.16.10.2 0.0.0.0 area 0
LabB(config-router)#
net 172.16.20.1 0.0.0.0 area 0
01:26:36: %OSPF-5-ADJCHG: Process 101, Nbr 172.16.10.1
on FastEthernet0/0 from LOADING to FULL, Loading Done
LabB#
show ip ospf neighbor
Neighbor ID Pri State Dead Time Address Interface
172.16.10.1 1 FULL/DR 00:00:33 172.16.10.1
LabB#
show ip ospf database
OSPF Router with ID (172.16.20.1) (Process ID 101)
Router Link States (Area 0)
Link ID ADV Router Age Seq# Checksum Link count
172.16.10.1 172.16.10.1 145 0x80000002 0x0067cd 1
172.16.20.1 172.16.20.1 32 0x80000003 0x006e8f 2
Net Link States (Area 0)
Link ID ADV Router Age Seq# Checksum
172.16.10.1 172.16.10.1 145 0x80000001 0x00953d
LabB#
show ip ospf interface
FastEthernet0/0 is up, line protocol is up
Internet address is 172.16.10.2/24, Area 0
Process ID 101, Router ID 172.16.20.1, Network Type BROADCAST, Cost: 1
Transmit Delay is 1 sec, State BDR, Priority 1
Designated Router (ID) 172.16.10.1, Interface address 172.16.10.1
Backup Designated Router (ID) 172.16.20.1, Interface address 172.16.10.2
Timer intervals configured, Hello 10, Dead 40, Wait 40, Retransmit 5
Hello due in 00:00:03
Index 1/1, flood queue length 0
Next 0x0(0)/0x0(0)
Last flood scan length is 1, maximum is 1
Last flood scan time is 0 msec, maximum is 0 msec
Neighbor Count is 1, Adjacent neighbor count is 1
Adjacent with neighbor 172.16.10.1 (Designated Router)
Suppress hello for 0 neighbor(s)
Serial0/0/0 is up, line protocol is up
Internet address is 172.16.20.1/24, Area 0
Process ID 101, Router ID 172.16.20.1, Network Type POINT-TO-POINT, Cost: 64
Transmit Delay is 1 sec, State POINT-TO-POINT,
Timer intervals configured, Hello 10, Dead 40, Wait 40, Retransmit 5
Hello due in 00:00:04
Index 2/2, flood queue length 0
Next 0x0(0)/0x0(0)
Last flood scan length is 1, maximum is 1
Last flood scan time is 0 msec, maximum is 0 msec
Suppress hello for 0 neighbor(s)
still looks good; same as before.... On to LabC router
LabC
LabC(config)#
router ospf 102
LabC(config-router)#
net 172.16.20.2 0.0.0.0 area 0
LabC(config-router)#
net 172.16.30.1 0.0.0.0 area 0
LabC(config-router)#
net 172.16.40.1 0.0.0.0 area 0
01:33:54: %OSPF-5-ADJCHG: Process 102, Nbr 172.16.20.1
on Serial0/0/0 from LOADING to FULL, Loading Done
LabC#
show ip ospf neighbor
[no output]
And here is where I ran into trouble. The show ip ospf neighbor command returns nothing. How can
that be?
After awhile I realized it is due to a misconfiguration in the topology.
For Lab C, I programmed the interfaces as follows:
LabC(config)#
int f0/0
LabC(config-if)#
ip addr 172.16.30.1 255.255.255.0
LabC(config-if)#
no shut
LabC(config-if)#
int s0/0/0
LabC(config-if)#
ip addr 172.16.20.2 255.255.255.0
LabC(config-if)#
no shut
LabC(config-if)#
int s0/0/1
LabC(config-if)#
ip addr 172.16.40.1 255.255.255.0
LabC(config-if)#
no shut
and again here is the topology for that router:
but here is what it SHOULD HAVE looked like (as it did the first time I built it)
S0/0/0 and S0/0/1 are swapped. When I gave the IP 172.16.20.2 to s/0/0/0, thinking that was the interface on the left side
which faces Lab B, I was actually giving 172.16.20.2 to the right side, facing LabC (which has no OSPF configs yet.)
Since the left side got got the IP intended for the right side which was 172.16.40.1
the inverse also occured-
the right side got the IP intended for the left which was 172.16.20.2
LabC left side should have been
s0/0/0 with 20.2
and LabC right side should have been
s0/0/1 with 40.1
The correct IPs were mapped to the correct interfaces. But the mistake happened before I even programmed them.
When I made the connections from LabB to LabC and from LabD to LabC, I plugged then into the wrong ports.
Interestingly.. not only is this causing OSPF to not see B as a neighbor from C.. but B and C cannot ping eachother either.
@B the config is 172.16.20.1/24 @ S0/0/0
@C the config is 172.16.40.1/24 @ S/0/0/1
meaning they are not even on the same network! But the system is not throwing any errors or bringing it to my attention.
It just fails to connect.
To correct the issue, I simply deleted those two links and re-created them. Worth noting, I used the auto select cable here,
which does not ask which interface you want to use when attaching. Earlier I must have plugged the right side first, and
auto select plugged into 0/0/0.
This time I plugged into left side first.
Now LabC OSPF data is reading out correctly...
LabC
LabC(config)#
router ospf 102
LabC(config-router)#
net 172.16.20.2 0.0.0.0 area 0
LabC(config-router)#
net 172.16.30.1 0.0.0.0 area 0
LabC(config-router)#
net 172.16.40.1 0.0.0.0 area 0
01:33:54: %OSPF-5-ADJCHG: Process 102, Nbr 172.16.20.1
on Serial0/0/0 from LOADING to FULL, Loading Done
LabC#
show ip ospf neighbor
Neighbor ID Pri State Dead Time Address Interface
172.16.20.1 0 FULL/ - 00:00:30 172.16.20.1 Serial0/0/0
LabC#
show ip ospf database
OSPF Router with ID (172.16.40.1) (Process ID 102)
Router Link States (Area 0)
Link ID ADV Router Age Seq# Checksum Link count
172.16.10.1 172.16.10.1 542 0x80000002 0x0067cd 1
172.16.20.1 172.16.20.1 90 0x80000004 0x00a551 3
172.16.40.1 172.16.40.1 37 0x80000004 0x00e47c 4
Net Link States (Area 0)
Link ID ADV Router Age Seq# Checksum
172.16.10.1 172.16.10.1 542 0x80000001 0x00953d
LabC#
show ip ospf interface
Serial0/0/0 is up, line protocol is up
Internet address is 172.16.20.2/24, Area 0
Process ID 102, Router ID 172.16.40.1, Network Type POINT-TO-POINT, Cost: 64
Transmit Delay is 1 sec, State POINT-TO-POINT,
Timer intervals configured, Hello 10, Dead 40, Wait 40, Retransmit 5
Hello due in 00:00:01
Index 1/1, flood queue length 0
Next 0x0(0)/0x0(0)
Last flood scan length is 1, maximum is 1
Last flood scan time is 0 msec, maximum is 0 msec
Neighbor Count is 1 , Adjacent neighbor count is 1
Adjacent with neighbor 172.16.20.1
Suppress hello for 0 neighbor(s)
FastEthernet0/0 is up, line protocol is up
Internet address is 172.16.30.1/24, Area 0
Process ID 102, Router ID 172.16.40.1, Network Type BROADCAST, Cost: 1
Transmit Delay is 1 sec, State DR, Priority 1
Designated Router (ID) 172.16.40.1, Interface address 172.16.30.1
No backup designated router on this network
Timer intervals configured, Hello 10, Dead 40, Wait 40, Retransmit 5
Hello due in 00:00:02
Index 2/2, flood queue length 0
Next 0x0(0)/0x0(0)
Last flood scan length is 1, maximum is 1
Last flood scan time is 0 msec, maximum is 0 msec
Neighbor Count is 0, Adjacent neighbor count is 0
Suppress hello for 0 neighbor(s)
Serial0/0/1 is up, line protocol is up
Internet address is 172.16.40.1/24, Area 0
Process ID 102, Router ID 172.16.40.1, Network Type POINT-TO-POINT, Cost: 64
Transmit Delay is 1 sec, State POINT-TO-POINT,
Timer intervals configured, Hello 10, Dead 40, Wait 40, Retransmit 5
Hello due in 00:00:08
Index 3/3, flood queue length 0
Next 0x0(0)/0x0(0)
Last flood scan length is 1, maximum is 1
Last flood scan time is 0 msec, maximum is 0 msec
Suppress hello for 0 neighbor(s)
Which brings me to the original reason I re-created this topology... I was confused about the LINK COUNTS
here:
OSPF Router with ID (172.16.40.1) (Process ID 102)
Router Link States (Area 0)
Link ID ADV Router Age Seq# Checksum Link count
172.16.10.1 172.16.10.1 542 0x80000002 0x0067cd 1
172.16.20.1 172.16.20.1 90 0x80000004 0x00a551 3
172.16.40.1 172.16.40.1 37 0x80000004 0x00e47c 4
Net Link States (Area 0)
Link ID ADV Router Age Seq# Checksum
172.16.10.1 172.16.10.1 542 0x80000001 0x00953d
The steps of recreating the lab were helpful, but this link answered the question:
Here is the output of each router's command show ip ospf interface as they are
set up one at a time.
LabA - No OSPF at B, C, or D yet
show ip ospf database
OSPF Router with ID (172.16.10.1) (Process ID 100)
Router Link States (Area 0)
Link ID ADV Router Age Seq# Checksum Link count
172.16.10.1 172.16.10.1 44 0x80000001 0x00b24b 1
LabB - No OSPF at C or D yet
show ip ospf database
OSPF Router with ID (172.16.20.1) (Process ID 101)
Router Link States (Area 0)
Link ID ADV Router Age Seq# Checksum Link count
172.16.10.1 172.16.10.1 145 0x80000002 0x0067cd 1
172.16.20.1 172.16.20.1 32 0x80000003 0x006e8f 2
Net Link States (Area 0)
Link ID ADV Router Age Seq# Checksum
172.16.10.1 172.16.10.1 145 0x80000001 0x00953d
the 20.2 interface on this router has 2 ospf links.
The left-facing out to RA, a crossover cable
The right-facing out to RC, a serial cable.
If the solution I found is correct, why is this serial link not being counted twice? The solution (I think)
is revealed after the configuration of the next router...
LabC - No OSPF at D yet
show ip ospf database
OSPF Router with ID (172.16.40.1) (Process ID 102)
Router Link States (Area 0)
Link ID ADV Router Age Seq# Checksum Link count
172.16.10.1 172.16.10.1 542 0x80000002 0x0067cd 1
172.16.20.1 172.16.20.1 90 0x80000004 0x00a551 3
172.16.40.1 172.16.40.1 37 0x80000004 0x00e47c 4
Net Link States (Area 0)
Link ID ADV Router Age Seq# Checksum
172.16.10.1 172.16.10.1 542 0x80000001 0x00953d
NOW we can see that the 20.1 link, which is the right-facing interface on LabB.. aka the router ID..
has THREE OSPF links.
Nothing changed on the left side of B. But on the right side, we now have an active OSPF router at the
other end of the link. This leads me to believe that the forum post was correct that 'serial links are counted twice',
but, more specifically, BOTH ENDS of the serial(PPP) link are counted... IF there is an OSPF router on each end.
This is backed up by the fact that LabC, OSPF id 40.1, has four OSPF links. The top-facing link to the 30
network DOES count.. even though it has no OSPF router on the other end. It counts because it's not a serial link.
The requirement of having an OSPF router on the other end for an interface to count here, only applies
to serial links. And pertains to BOTH ends of the link being counted.
In LabC's case, we have one serial at left, being counted twice. One ethernet at top, being counted once. And
one serial at right only being counted once because LabD is not active with OSPF yet.
If this is correct, then we should see Lab C's 40.1 count go to 5 after LabD is set for OSPF....
LabD - all 4 routers have OSPF
show ip ospf database
OSPF Router with ID (172.16.50.1) (Process ID 103)
Router Link States (Area 0)
Link ID ADV Router Age Seq# Checksum Link count
172.16.10.1 172.16.10.1 785 0x80000002 0x0067cd 1
172.16.20.1 172.16.20.1 333 0x80000004 0x00a551 3
172.16.40.1 172.16.40.1 111 0x80000005 0x00013b 5
172.16.50.1 172.16.50.1 53 0x80000003 0x001023 3
Net Link States (Area 0)
Link ID ADV Router Age Seq# Checksum
172.16.10.1 172.16.10.1 785 0x80000001 0x00953d
and back to LabC.....
show ip ospf database
OSPF Router with ID (172.16.40.1) (Process ID 102)
Router Link States (Area 0)
Link ID ADV Router Age Seq# Checksum Link count
172.16.10.1 172.16.10.1 1174 0x80000002 0x0067cd 1
172.16.20.1 172.16.20.1 722 0x80000004 0x00a551 3
172.16.40.1 172.16.40.1 500 0x80000005 0x00013b 5
172.16.50.1 172.16.50.1 441 0x80000003 0x001023 3
Net Link States (Area 0)
Link ID ADV Router Age Seq# Checksum
172.16.10.1 172.16.10.1 1174 0x80000001 0x00953d
Looks good! The link count for each router makes sense if you count the serial interfaces twice (one for each end).
the OSPF databases now match across all 4 routers.
NOTE that this is a database of routers, identified by
router ID. It is not a topology that lists routers AND routes, like in
the "equivalent" eigrp command show eigrp topology
Note that the .30 network is NOT represented here.
LabA#
show ip ospf database
OSPF Router with ID (172.16.10.1) (Process ID 100)
Router Link States (Area 0)
Link ID ADV Router Age Seq# Checksum Link count
172.16.10.1 172.16.10.1 1138 0x80000002 0x0067cd 1
172.16.20.1 172.16.20.1 686 0x80000004 0x00a551 3
172.16.40.1 172.16.40.1 463 0x80000005 0x00013b 5
172.16.50.1 172.16.50.1 404 0x80000003 0x001023 3
Net Link States (Area 0)
Link ID ADV Router Age Seq# Checksum
172.16.10.1 172.16.10.1 1138 0x80000001 0x00953d
LabB#
show ip ospf database
OSPF Router with ID (172.16.20.1) (Process ID 101)
Router Link States (Area 0)
Link ID ADV Router Age Seq# Checksum Link count
172.16.10.1 172.16.10.1 1151 0x80000002 0x0067cd 1
172.16.20.1 172.16.20.1 699 0x80000004 0x00a551 3
172.16.40.1 172.16.40.1 476 0x80000005 0x00013b 5
172.16.50.1 172.16.50.1 417 0x80000003 0x001023 3
Net Link States (Area 0)
Link ID ADV Router Age Seq# Checksum
172.16.10.1 172.16.10.1 1151 0x80000001 0x00953d
LabC#
show ip ospf database
OSPF Router with ID (172.16.40.1) (Process ID 102)
Router Link States (Area 0)
Link ID ADV Router Age Seq# Checksum Link count
172.16.10.1 172.16.10.1 1174 0x80000002 0x0067cd 1
172.16.20.1 172.16.20.1 722 0x80000004 0x00a551 3
172.16.40.1 172.16.40.1 500 0x80000005 0x00013b 5
172.16.50.1 172.16.50.1 441 0x80000003 0x001023 3
Net Link States (Area 0)
Link ID ADV Router Age Seq# Checksum
172.16.10.1 172.16.10.1 1174 0x80000001 0x00953d
LabD#
show ip ospf database
OSPF Router with ID (172.16.50.1) (Process ID 103)
Router Link States (Area 0)
Link ID ADV Router Age Seq# Checksum Link count
172.16.10.1 172.16.10.1 785 0x80000002 0x0067cd 1
172.16.20.1 172.16.20.1 333 0x80000004 0x00a551 3
172.16.40.1 172.16.40.1 111 0x80000005 0x00013b 5
172.16.50.1 172.16.50.1 53 0x80000003 0x001023 3
Net Link States (Area 0)
Link ID ADV Router Age Seq# Checksum
172.16.10.1 172.16.10.1 785 0x80000001 0x00953d
Below is our routing tables with OSPF data. We do see the .30 network here.
Everyone can reach it:
LabA via LabB's 10.2
LabB via LabC's 20.2
LabC via direct connection
LabD via LabC's 40.1
LabA#
show ip route
172.16.0.0/16 is variably subnetted, 6 subnets, 2 masks
C 172.16.10.0/24 is directly connected, FastEthernet0/0
L 172.16.10.1/32 is directly connected, FastEthernet0/0
O 172.16.20.0/24 [110/65] via 172.16.10.2, 00:28:03, FastEthernet0/0
O 172.16.30.0/24 [110/66] via 172.16.10.2, 00:21:35, FastEthernet0/0
O 172.16.40.0/24 [110/129] via 172.16.10.2, 00:21:25, FastEthernet0/0
O 172.16.50.0/24 [110/130] via 172.16.10.2, 00:17:40, FastEthernet0/0
LabB#
show ip route
172.16.0.0/16 is variably subnetted, 7 subnets, 2 masks
C 172.16.10.0/24 is directly connected, FastEthernet0/0
L 172.16.10.2/32 is directly connected, FastEthernet0/0
C 172.16.20.0/24 is directly connected, Serial0/0/0
L 172.16.20.1/32 is directly connected, Serial0/0/0
O 172.16.30.0/24 [110/65] via 172.16.20.2, 00:27:04, Serial0/0/0
O 172.16.40.0/24 [110/128] via 172.16.20.2, 00:26:54, Serial0/0/0
O 172.16.50.0/24 [110/129] via 172.16.20.2, 00:23:09, Serial0/0/0
LabC#
show ip route
172.16.0.0/16 is variably subnetted, 8 subnets, 2 masks
O 172.16.10.0/24 [110/65] via 172.16.20.1, 00:27:52, Serial0/0/0
C 172.16.20.0/24 is directly connected, Serial0/0/0
L 172.16.20.2/32 is directly connected, Serial0/0/0
C 172.16.30.0/24 is directly connected, FastEthernet0/0
L 172.16.30.1/32 is directly connected, FastEthernet0/0
C 172.16.40.0/24 is directly connected, Serial0/0/1
L 172.16.40.1/32 is directly connected, Serial0/0/1
O 172.16.50.0/24 [110/65] via 172.16.40.2, 00:23:36, Serial0/0/1
LabD#
show ip route
172.16.0.0/16 is variably subnetted, 7 subnets, 2 masks
O 172.16.10.0/24 [110/129] via 172.16.40.1, 00:25:20, Serial0/0/0
O 172.16.20.0/24 [110/128] via 172.16.40.1, 00:25:20, Serial0/0/0
O 172.16.30.0/24 [110/65] via 172.16.40.1, 00:25:20, Serial0/0/0
C 172.16.40.0/24 is directly connected, Serial0/0/0
L 172.16.40.2/32 is directly connected, Serial0/0/0
C 172.16.50.0/24 is directly connected, FastEthernet0/0
L 172.16.50.1/32 is directly connected, FastEthernet0/0
moving on.......
9.5 - OSPF DR and BDR Elections
EachRouter(config)#
hostname X (A, B, or C)
EachRouter(config)#
line con 0
EachRouter(config-line)#
exec-timeout 0 0
A(config)#
int f0/0
A(config-if)#
ip addr 10.1.1.1 255.255.255.0
A(config-if)#
no shut
A(config)#
router ospf 12345
A(config-router)#
net 10.1.1.0 0.0.0.255 area 0
00:23:30: %OSPF-5-ADJCHG: Process 12345, Nbr 10.1.1.3 on FastEthernet0/0 from LOADING to FULL, Loading Done
00:23:30: %OSPF-5-ADJCHG: Process 12345, Nbr 10.1.1.2 on FastEthernet0/0 from LOADING to FULL, Loading Done
A#
show ip ospf int
note this output was generated AFTER all 3 routers set for OSPF
FastEthernet0/0 is up, line protocol is up
Internet address is 10.1.1.1/24, Area 0
Process ID 12345, Router ID 10.1.1.1, Network Type BROADCAST, Cost: 1
Transmit Delay is 1 sec, State DROTHER, Priority 1
Designated Router (ID) 10.1.1.3, Interface address 10.1.1.3
Backup Designated Router (ID) 10.1.1.2, Interface address 10.1.1.2
Timer intervals configured, Hello 10, Dead 40, Wait 40, Retransmit 5
Hello due in 00:00:04
Index 1/1, flood queue length 0
Next 0x0(0)/0x0(0)
Last flood scan length is 1, maximum is 1
Last flood scan time is 0 msec, maximum is 0 msec
Neighbor Count is 2, Adjacent neighbor count is 2
Adjacent with neighbor 10.1.1.3 (Designated Router)
Adjacent with neighbor 10.1.1.2 (Backup Designated Router)
Suppress hello for 0 neighbor(s)
A(config-if)#shut
A(config-if)#
%LINK-5-CHANGED: Interface FastEthernet0/0, changed state to administratively down
%LINEPROTO-5-UPDOWN: Line protocol on Interface FastEthernet0/0, changed state to down
00:40:28: %OSPF-5-ADJCHG: Process 12345, Nbr 10.1.1.2 on FastEthernet0/0 from FULL to DOWN, Neighbor Down: Interface down or detached
00:40:28: OSPF: Build router LSA for area 0, router ID 10.1.1.1, seq 0xffffffff80000003
00:40:28: %OSPF-5-ADJCHG: Process 12345, Nbr 10.1.1.3 on FastEthernet0/0 from FULL to DOWN, Neighbor Down: Interface down or detached
00:40:28: OSPF: Build router LSA for area 0, router ID 10.1.1.1, seq 0xffffffff80000004
00:40:28: OSPF: Build router LSA for area 0, router ID 10.1.1.1, seq 0xffffffff80000004
A(config-if)#no shut
A(config-if)#
%LINK-5-CHANGED: Interface FastEthernet0/0, changed state to up
%LINEPROTO-5-UPDOWN: Line protocol on Interface FastEthernet0/0, changed state to up
00:40:48: OSPF: Build router LSA for area 0, router ID 10.1.1.1, seq 0xffffffff80000004
00:41:27: OSPF: Backup seen Event before WAIT timer on FastEthernet0/0
00:41:27: OSPF: DR/BDR election on FastEthernet0/0
00:41:27: OSPF: Elect BDR 10.1.1.2
00:41:27: OSPF: Elect DR 10.1.1.3
00:41:27: DR: 10.1.1.3 (Id) BDR: 10.1.1.2 (Id)
00:41:27: OSPF: Send DBD to 10.1.1.3 on FastEthernet0/0 seq 0x5accb8e2 opt 0x00 flag 0x7 len 32
B(config)#
int f0/0
B(config-if)#
ip addr 10.1.1.2 255.255.255.0
B(config-if)#
no shut
B(config)#
router ospf 12345
B(config-router)#
net 10.1.1.0 0.0.0.255 area 0
00:23:29: %OSPF-5-ADJCHG: Process 12345, Nbr 10.1.1.3 on FastEthernet0/0 from LOADING to FULL, Loading Done
00:23:29: %OSPF-5-ADJCHG: Process 12345, Nbr 10.1.1.1 on FastEthernet0/0 from LOADING to FULL, Loading Done
B#
show ip ospf int
note this output was generated AFTER all 3 routers set for OSPF
FastEthernet0/0 is up, line protocol is up
Internet address is 10.1.1.2/24, Area 0
Process ID 12345, Router ID 10.1.1.2, Network Type BROADCAST, Cost: 1
Transmit Delay is 1 sec, State BDR, Priority 1
Designated Router (ID) 10.1.1.3, Interface address 10.1.1.3
Backup Designated Router (ID) 10.1.1.2, Interface address 10.1.1.2
Timer intervals configured, Hello 10, Dead 40, Wait 40, Retransmit 5
Hello due in 00:00:05
Index 1/1, flood queue length 0
Next 0x0(0)/0x0(0)
Last flood scan length is 1, maximum is 1
Last flood scan time is 0 msec, maximum is 0 msec
Neighbor Count is 2, Adjacent neighbor count is 2
Adjacent with neighbor 10.1.1.1
Adjacent with neighbor 10.1.1.3 (Designated Router)
Suppress hello for 0 neighbor(s)
B#debug ip ospf adj
OSPF adjacency events debugging is on
B#
00:39:21: OSPF: DR/BDR election on FastEthernet0/0
00:39:21: OSPF: Elect BDR 10.1.1.2
00:39:21: OSPF: Elect DR 10.1.1.3
00:39:21: DR: 10.1.1.3 (Id) BDR: 10.1.1.2 (Id)
00:41:01: %OSPF-5-ADJCHG: Process 12345, Nbr 10.1.1.1 on FastEthernet0/0 from FULL to DOWN, Neighbor Down: Dead timer expired
00:41:01: %OSPF-5-ADJCHG: Process 12345, Nbr 10.1.1.1 on FastEthernet0/0 from FULL to DOWN, Neighbor Down: Interface down or detached
00:41:01: OSPF: Build router LSA for area 0, router ID 10.1.1.2, seq 0xffffffff80000003
00:41:01: OSPF: DR/BDR election on FastEthernet0/0
00:41:01: OSPF: Elect BDR 10.1.1.2
00:41:01: OSPF: Elect DR 10.1.1.3
C(config)#
int f0/0
C(config-if)#
ip addr 10.1.1.3 255.255.255.0
C(config-if)#
no shut
C(config)#
router ospf 12345
C(config-router)#
net 10.1.1.0 0.0.0.255 area 0
00:23:27: %OSPF-5-ADJCHG: Process 12345, Nbr 10.1.1.1 on FastEthernet0/0 from LOADING to FULL, Loading Done
00:23:27: %OSPF-5-ADJCHG: Process 12345, Nbr 10.1.1.2 on FastEthernet0/0 from LOADING to FULL, Loading Done
C#
show ip ospf int
note this output was generated AFTER all 3 routers set for OSPF
FastEthernet0/0 is up, line protocol is up
Internet address is 10.1.1.3/24, Area 0
Process ID 12345, Router ID 10.1.1.3, Network Type BROADCAST, Cost: 1
Transmit Delay is 1 sec, State DR, Priority 1
Designated Router (ID) 10.1.1.3, Interface address 10.1.1.3
Backup Designated Router (ID) 10.1.1.2, Interface address 10.1.1.2
Timer intervals configured, Hello 10, Dead 40, Wait 40, Retransmit 5
Hello due in 00:00:00
Index 1/1, flood queue length 0
Next 0x0(0)/0x0(0)
Last flood scan length is 1, maximum is 1
Last flood scan time is 0 msec, maximum is 0 msec
Neighbor Count is 2, Adjacent neighbor count is 2
Adjacent with neighbor 10.1.1.1
Adjacent with neighbor 10.1.1.2 (Backup Designated Router)
Suppress hello for 0 neighbor(s)
C#debug ip ospf adj
OSPF adjacency events debugging is on
C#
00:39:19: OSPF: DR/BDR election on FastEthernet0/0
00:39:19: OSPF: Elect BDR 10.1.1.2
00:39:19: OSPF: Elect DR 10.1.1.3
00:39:19: DR: 10.1.1.3 (Id) BDR: 10.1.1.2 (Id)
00:40:59: %OSPF-5-ADJCHG: Process 12345, Nbr 10.1.1.1 on FastEthernet0/0 from FULL to DOWN, Neighbor Down: Dead timer expired
00:40:59: %OSPF-5-ADJCHG: Process 12345, Nbr 10.1.1.1 on FastEthernet0/0 from FULL to DOWN, Neighbor Down: Interface down or detached
00:40:59: OSPF: Build router LSA for area 0, router ID 10.1.1.3, seq 0xffffffff80000003
00:40:59: OSPF: Build net LSA for area 0, router ID 10.1.1.3, seq 0xffffffff80000003
00:40:59: OSPF: DR/BDR election on FastEthernet0/0
00:40:59: OSPF: Elect BDR 10.1.1.2
00:40:59: OSPF: Elect DR 10.1.1.3
DR and BDR automtically set based on higest IP address
Note our network type is BROADCAST because we're using ethernet interfaces...
it would be point-to-point if using a serial connection
we want to manually overide the priority of the router. ZERO priority means it wont participate in the election process
MAX priority of 255 means no other router can beat it for DR
We'll set the priority for router A to 3.
It will beome the DR only after we shut/no shut the interface router
AND
manually power on/off the other two routers
A(config)#
int f0/0
A(config-int)#
ip ospf priority 3
A(config-int)#
shut
A(config-int)#
no shut
A#
debug ip ospf adj
B#
debug ip ospf adj
00:05:50: OSPF: DR/BDR election on FastEthernet0/0
00:05:50: OSPF: Elect BDR 10.1.1.2
00:05:50: OSPF: Elect DR 10.1.1.1
00:05:50: OSPF: Elect BDR 10.1.1.2
00:05:50: OSPF: Elect DR 10.1.1.1
00:05:50: DR: 10.1.1.1 (Id) BDR: 10.1.1.2 (Id)
00:05:50: OSPF: Send DBD to 10.1.1.1 on FastEthernet0/0 seq 0x10164ebb opt 0x00 flag 0x7 len 32
00:05:50: OSPF: Build router LSA for area 0, router ID 10.1.1.2, seq 0xffffffff80000002
00:05:52: OSPF: Rcv DBD from 10.1.1.1 on FastEthernet0/0 seq 0x20368093 opt 0x00 flag 0x7 len 32 mtu 1500 state EXSTART
00:05:52: OSPF: First DBD and we are not SLAVE
00:05:55: OSPF: Send DBD to 10.1.1.1 on FastEthernet0/0 seq 0x10164ebb opt 0x00 flag 0x7 len 32
00:05:55: OSPF: Rcv DBD from 10.1.1.1 on FastEthernet0/0 seq 0x10164ebb opt 0x00 flag 0x2 len 112 mtu 1500 state EXSTART
00:05:55: OSPF: NBR Negotiation Done. We are the MASTER
00:05:55: OSPF: Send DBD to 10.1.1.1 on FastEthernet0/0 seq 0x10164ebc opt 0x00 flag 0x3 len 52
00:05:55: OSPF: Rcv DBD from 10.1.1.1 on FastEthernet0/0 seq 0x10164ebc opt 0x00 flag 0x0 len 32 mtu 1500 state EXCHANGE
00:05:55: OSPF: Send DBD to 10.1.1.1 on FastEthernet0/0 seq 0x10164ebd opt 0x00 flag 0x1 len 32
00:05:55: OSPF: Rcv DBD from 10.1.1.1 on FastEthernet0/0 seq 0x10164ebd opt 0x00 flag 0x0 len 32 mtu 1500 state EXCHANGE
00:05:55: Exchange Done with 10.1.1.1 on FastEthernet0/0
00:05:55: OSPF: Database request to 10.1.1.1
00:05:55: OSPF: sent LS REQ packet to 10.1.1.1, length 36
00:05:55: OSPF: Rcv DBD from 10.1.1.1 on FastEthernet0/0 seq 0x10164ebd opt 0x00 flag 0x0 len 32 mtu 1500 state LOADING
00:05:55: Synchronized with with 10.1.1.1 on FastEthernet0/0, state FULL
00:05:55: %OSPF-5-ADJCHG: Process 12345, Nbr 10.1.1.1 on FastEthernet0/0 from LOADING to FULL, Loading Done
00:05:55: OSPF: Build router LSA for area 0, router ID 10.1.1.2, seq 0xffffffff80000002
C#
debug ip ospf adj
00:06:13: OSPF: DR/BDR election on FastEthernet0/0
00:06:13: OSPF: Elect BDR 10.1.1.2
00:06:13: OSPF: Elect DR 10.1.1.1
00:06:13: DR: 10.1.1.1 (Id) BDR: 10.1.1.2 (Id)
00:06:13: OSPF: Send DBD to 10.1.1.1 on FastEthernet0/0 seq 0x1cc5536d opt 0x00 flag 0x7 len 32
00:06:13: OSPF: Send DBD to 10.1.1.2 on FastEthernet0/0 seq 0x3d51ca66 opt 0x00 flag 0x7 len 32
00:06:13: OSPF: Build router LSA for area 0, router ID 10.1.1.3, seq 0xffffffff80000002
00:06:17: OSPF: Rcv DBD from 10.1.1.1 on FastEthernet0/0 seq 0x6b532eec opt 0x00 flag 0x7 len 32 mtu 1500 state EXSTART
00:06:17: OSPF: First DBD and we are not SLAVE
00:06:17: OSPF: Rcv DBD from 10.1.1.2 on FastEthernet0/0 seq 0x783110f4 opt 0x00 flag 0x7 len 32 mtu 1500 state EXSTART
00:06:17: OSPF: First DBD and we are not SLAVE
00:06:18: OSPF: Send DBD to 10.1.1.2 on FastEthernet0/0 seq 0x3d51ca66 opt 0x00 flag 0x7 len 32
00:06:18: OSPF: Send DBD to 10.1.1.1 on FastEthernet0/0 seq 0x1cc5536d opt 0x00 flag 0x7 len 32
00:06:18: OSPF: Rcv DBD from 10.1.1.2 on FastEthernet0/0 seq 0x3d51ca66 opt 0x00 flag 0x2 len 132 mtu 1500 state EXSTART
00:06:18: OSPF: NBR Negotiation Done. We are the MASTER
00:06:18: OSPF: Send DBD to 10.1.1.2 on FastEthernet0/0 seq 0x3d51ca67 opt 0x00 flag 0x3 len 52
00:06:18: OSPF: Rcv DBD from 10.1.1.1 on FastEthernet0/0 seq 0x1cc5536d opt 0x00 flag 0x2 len 132 mtu 1500 state EXSTART
00:06:18: OSPF: NBR Negotiation Done. We are the MASTER
00:06:18: OSPF: Send DBD to 10.1.1.1 on FastEthernet0/0 seq 0x1cc5536e opt 0x00 flag 0x3 len 52
00:06:18: OSPF: Rcv DBD from 10.1.1.2 on FastEthernet0/0 seq 0x3d51ca67 opt 0x00 flag 0x0 len 32 mtu 1500 state EXCHANGE
00:06:18: OSPF: Send DBD to 10.1.1.2 on FastEthernet0/0 seq 0x3d51ca68 opt 0x00 flag 0x1 len 32
00:06:18: OSPF: Rcv DBD from 10.1.1.1 on FastEthernet0/0 seq 0x1cc5536e opt 0x00 flag 0x0 len 32 mtu 1500 state EXCHANGE
00:06:18: OSPF: Send DBD to 10.1.1.1 on FastEthernet0/0 seq 0x1cc5536f opt 0x00 flag 0x1 len 32
00:06:18: OSPF: Rcv DBD from 10.1.1.2 on FastEthernet0/0 seq 0x3d51ca68 opt 0x00 flag 0x0 len 32 mtu 1500 state EXCHANGE
00:06:18: Exchange Done with 10.1.1.2 on FastEthernet0/0
00:06:18: OSPF: Database request to 10.1.1.2
00:06:18: OSPF: sent LS REQ packet to 10.1.1.2, length 48
00:06:18: OSPF: Rcv DBD from 10.1.1.1 on FastEthernet0/0 seq 0x1cc5536f opt 0x00 flag 0x0 len 32 mtu 1500 state EXCHANGE
verify on all three routers
A#
show ip ospf interface f0/0
FastEthernet0/0 is up, line protocol is up
Internet address is 10.1.1.1/24, Area 0
Process ID 12345, Router ID 10.1.1.1, Network Type BROADCAST, Cost: 1
Transmit Delay is 1 sec, State DR, Priority 3
Designated Router (ID) 10.1.1.1, Interface address 10.1.1.1
Backup Designated Router (ID) 10.1.1.2, Interface address 10.1.1.2
Timer intervals configured, Hello 10, Dead 40, Wait 40, Retransmit 5
Hello due in 00:00:09
Index 1/1, flood queue length 0
Next 0x0(0)/0x0(0)
Last flood scan length is 1, maximum is 1
Last flood scan time is 0 msec, maximum is 0 msec
Neighbor Count is 2, Adjacent neighbor count is 2
Adjacent with neighbor 10.1.1.2 (Backup Designated Router)
Adjacent with neighbor 10.1.1.3
Suppress hello for 0 neighbor(s)
A#
show ip ospf neighbor
Neighbor ID Pri State Dead Time Address Interface
10.1.1.2 1 FULL/BDR 00:00:37 10.1.1.2 FastEthernet0/0
10.1.1.3 1 FULL/DROTHER 00:00:30 10.1.1.3 FastEthernet0/0
B#
show ip ospf interface f0/0
FastEthernet0/0 is up, line protocol is up
Internet address is 10.1.1.2/24, Area 0
Process ID 12345, Router ID 10.1.1.2, Network Type BROADCAST, Cost: 1
Transmit Delay is 1 sec, State BDR, Priority 1
Designated Router (ID) 10.1.1.1, Interface address 10.1.1.1
Backup Designated Router (ID) 10.1.1.2, Interface address 10.1.1.2
Timer intervals configured, Hello 10, Dead 40, Wait 40, Retransmit 5
Hello due in 00:00:08
Index 1/1, flood queue length 0
Next 0x0(0)/0x0(0)
Last flood scan length is 1, maximum is 1
Last flood scan time is 0 msec, maximum is 0 msec
Neighbor Count is 2, Adjacent neighbor count is 2
Adjacent with neighbor 10.1.1.1 (Designated Router)
Adjacent with neighbor 10.1.1.3
Suppress hello for 0 neighbor(s)
B#
show ip ospf neighbor
Neighbor ID Pri State Dead Time Address Interface
10.1.1.1 3 FULL/DR 00:00:35 10.1.1.1 FastEthernet0/0
10.1.1.3 1 FULL/DROTHER 00:00:31 10.1.1.3 FastEthernet0/0
C#
show ip ospf interface f0/0
FastEthernet0/0 is up, line protocol is up
Internet address is 10.1.1.3/24, Area 0
Process ID 12345, Router ID 10.1.1.3, Network Type BROADCAST, Cost: 1
Transmit Delay is 1 sec, State DROTHER, Priority 1
Designated Router (ID) 10.1.1.1, Interface address 10.1.1.1
Backup Designated Router (ID) 10.1.1.2, Interface address 10.1.1.2
Timer intervals configured, Hello 10, Dead 40, Wait 40, Retransmit 5
Hello due in 00:00:06
Index 1/1, flood queue length 0
Next 0x0(0)/0x0(0)
Last flood scan length is 1, maximum is 1
Last flood scan time is 0 msec, maximum is 0 msec
Neighbor Count is 2, Adjacent neighbor count is 2
Adjacent with neighbor 10.1.1.1 (Designated Router)
Adjacent with neighbor 10.1.1.2 (Backup Designated Router)
Suppress hello for 0 neighbor(s)
C#
show ip ospf neighbor/span>
Neighbor ID Pri State Dead Time Address Interface
10.1.1.1 3 FULL/DR 00:00:35 10.1.1.1 FastEthernet0/0
10.1.1.2 1 FULL/BDR 00:00:37 10.1.1.2 FastEthernet0/0
Router1 is the DR with priority 3
still need more work to understand the output of the defbu ospf adj
Chapter 9 Review Questions
1. There are three possible routes for a router to reach a destination network:
OSPF with a metric of 782
RIPv2 with a metric of 4
EIGRP with a composite metric of 20514560
Which route will be installed in the routing table?
EIGRP because it has the lowest Administrative Distance, and AD is always used before metric
ADs are:
ExternalEIGRP 170
RIP 120
OSPF 110
IGRP 100
EIGRP 90
Static 1
Connected 0
2. Which EIGRP information is held in RAM and maintained through the use of Hello and update packets?
Neighbor table
and
toplogy table
3. Describe the process identifier that is used to run OSPF on a router
The OSPF process id is only locally significant. A random number can be selected. But it's required in order to identify
a unique OSPF database instance. You can use the same, or a different number on each router, doesnt matter.
Any number can be used from 1 to 65,535. Process ID is supplied as an argument to the command router ospf
NOT to be confused with the area number which can be any number up to 4 billion. The area id identifies a logical grouping of routers.
area id is supplied as argument to the OSPF network id and mask command
Ex:
R1(config)#
router ospf 12345
R1(config-router)#
net 10.1.1.0 0.0.0.255 area 0
4. Where are EIGRP successor routes stored?
EIGRP succesor routers are stored in the routing table. The "succesor" is the successful or primary route.
The successor route is ALSO listed in the topology table,
The feasible successor is a BACKUP route and will ONLY be listed in the topology table, unless the successor route fails,
in which case the feasible successor would become the successor
Note that my EIGRP setup doesnt seem to folow this.
CTRL-F jump to "remotely connected via remote ingress ip address"
the book states that EIGRP is automatically load-balancing our two links from R1 to corp.. is this why there is no feasible successor here?
I did some research and found that in our case, we are not using a Feasible Successor. You CAN have two Successors with equal metric, in which case EIGRP will
automatically load-balance.
But I wanted to find out what a Feasible Successor actually looks like in the EIGRP topology table..
Kevin Wallace EIGRP article
Conclusion:
EIGRP topology table wouldnt specifically say "Feasible Successor", but you would know by two routes appearing, one with a lower metric.
In my topology we have two equal-metric links and they are both considered "Successors". EIGRP uses them equally (load-balanced)
Corp#
show ip eigrp toplogy
[cut]
P 172.16.10.0/24, 1 successors, FD is 28160
via 10.1.5.2 (28160/25600), FastEthernet0/0
P 192.168.10.0/24, 2 successors, FD is 2172416
via 10.1.3.2 (2172416/28160), Serial0/0/1
via 10.1.2.2 (2172416/28160), Serial0/0/0
P 192.168.20.0/24, 2 successors, FD is 2172416
via 10.1.3.2 (2172416/28160), Serial0/0/1
via 10.1.2.2 (2172416/28160), Serial0/0/0
P 192.168.30.0/24, 1 successors, FD is 2172416
via 10.1.4.2 (2172416/28160), Serial0/1/0
P 192.168.40.0/24, 1 successors, FD is 2172416
via 10.1.4.2 (2172416/28160), Serial0/1/0
5. Which command will display all the EIGRP feasible successor routes to a known router.
show ip eigrp topology
6. Find the configuration error. You type the following into your router, but dont see any routes in the routing table?
Router(config)#
router ospf 1
Router(config-router)#
network 10.0.0.0 255.0.0.0
wrong wildcard mask
instead, could have used
0.255.255.255
or
0.0.0.255
the point is we need to specify the first octet as "allowed" into our OSPF config with a 0 mask.
The remaining bits are 'dont care' bits aka 'wildcard' aka 255
7. Which three protocols support VLSM, summarization, and discontigous networking?
RIPv2
EIGRP
OSPF
all 3 build and mainting routing tables, provide classless routing which allows VLSM, summarization, and discontigous networks
RIPv1 and IGRP build/maintain routing tables, but dont offer classless routing
8. Which are true regarding OSPF areas?
the 'backbone' is area 0
if using other areas, they all must directly connect to area 0
9. Which two network types have a designated router and a backup designated router?
Broadcast
NBMA- Non broadcast multi access. Ex: Frame Relay
network types that DO NOT use DR/BDR:
point to point
broadcast multipoint
10. You need to configure a router with a distance-vector protocol that allows classless routing. Which to use?
EIGRP is considered 'advanced distance vector' (ripv2 wasnt an option)
11. You need the IP address of the devices with which the router has established an adjacency.
Also, the retransmit interval and the queue counts for the adjacent routers need to be checked. What command will display the required information?
show ip eigrp neighbors
WRONG: show ip eigrp adjacency - there is no such command.. the word 'adjacency' is only used with debug ip OSPF adjacency
here are the possible commands for show ip eigrp and debug ip eigrp
show ip eigrp ?
interfaces IP-EIGRP interfaces
neighbors IP-EIGRP neighbors
topology IP-EIGRP Topology Table
traffic IP-EIGRP Traffic Statistics
debug ip eigrp ?
summary IP-EIGRP summary route processing
12. You cant establish an adjacency relationship on a common ethernet link between two routers. Based on the output below, what is the cause of the problem?
RouterA#
Ethernet0/0 is up, line protocol is up
Internet Address 172.16.1.2/16, Area 0
Process ID 2, Router ID 172.126.1.2, Network Type BROADCAST, Cost: 10
Transmit Delay is 1 sec, State DR, Priority 1
Designated Router (ID) 172.16.1.2, interface address 172.16.1.1.
No backup designated router on this network
Timer intervals configured, Hello 5, Dead 20, Wait 20, Retransmit 5
Router B#
Internet Address 172.16.1.1/16, Area 0
Process ID 2, Router ID 172.126.1.1, Network Type BROADCAST, Cost: 10
Transmit Delay is 1 sec, State DR, Priority 1
Designated Router (ID) 172.16.1.1, interface address 172.16.1.2.
No backup designated router on this network
Timer intervals configured, Hello 10, Dead 40, Wait 40, Retransmit 5
mismatched timer intervals
OSPF default Hello is 10 and Dead is 40... RouterA was modified
13. Which is true regarding EIGRP successor routes?
Used in the routing table
also appears in the topolgy table
may (or may not) have a backup feasabile successor
14. Which type of OSPF network will elect a backup designated router?
broadcast multi-access
non-broadcast multiaccess
types of network that will NOT elect a BDR:
point to point and brodacast multipoint (hub/spoke topology)
15. Which two commands will place network 10.2.3.0/24 into area 0?
Router(config)#
router ospf 10
Router(config-router)#
network 10.2.3.0 0.0.0.255 area 0
16. With which network type will OSPF establish router adjacencies but not perform the DR/BDR election process?
Point to point
no election process occurs, there is never a DR on point to point
17. What are three reasons for creating OSPF in a heirarchical design?
decrease routing overhead
speed up convergence
confine stability to single areas of the network
18. What is the administrative distance of OSPF?
110
19.
no auto summary
the network is considered discontigous because we have two classful network subnetted (on the left and right),
seperated by a different classful address.
if auto summarization is taking place, the routers cant determine which side is which because both sides would be summarized as
Class B, 172.16.0.0, which isnt specific enough to distinguish between the sides.
20. IF routers in a single area are configured with the same priority value, what value does a router use for the OSPF router ID in the absence of a loopback interface?
The highest IP of any PHSYICAL interface.
Trick question. Highest IP of any LOGICAL interface is an option. And is correct IF you had logical interfaces, but the question
states that any "logical interfaces are absent".
At OSPF startup, the highest IP of *any* active interface on the router becomes the OSPF router ID. If you have loopback (logical) interfaces configured,
one of them (the largest IP) will *override* the phsyical interfaces and the loopback IP becomes the RID.
Reference for which loopback (if multiple) wins:
packetpushers.net
------------------------------------------------------------------------------
END CHAPTER 9
41 hours 2-14 thru 2-28-22
original total 184 hours
14 hours review 12-26 thru 12-28-22
review total hours 46
book page 502/822
184 + 46 = 230 hours * 60 = (13,800 min) / 500 pages =
avg 28 min/page (includes reading and exercises/labs + online research)
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router#
?
router# cl?
clear clock
router# clock ?
set Set the date and time
router# clock set 10:30:30 ?
<1-31> Day of the month
MONTH Month of the year
router# clock set 10:30:30 17 January 2022
router#
router# show clock
10:31:33.95 UTC Mon Jan 17 2022
keyboard commands
ctrl + A
beginning of line
ctrl + E
end of line
ctrl + B
back one character
ctrl + F
forward one character
ctrl + P
paste previous command
TAB
complete a partially typed command
router# terminal no editing
turns off the keyboard shortcuts
router# terminal editing
turns on the keyboard shortcuts
router# show history
shows last 10 commands by default
router# terminal history size 20
sets the history size to 20
router# cl?
clear clock
router# clock ?
set Set the date and time
router# clock set 10:30:30 ?
<1-31> Day of the month
MONTH Month of the year
router# clock set 10:30:30 17 January 2022
router#
router# show clock
10:31:33.95 UTC Mon Jan 17 2022
keyboard commands
ctrl + A
beginning of line
ctrl + E
end of line
ctrl + B
back one character
ctrl + F
forward one character
ctrl + P
paste previous command
TAB
complete a partially typed command
router# terminal no editing
turns off the keyboard shortcuts
router# terminal editing
turns on the keyboard shortcuts
router# show history
shows last 10 commands by default
router# terminal history size 20
sets the history size to 20
router# show startup-config
"startup config" AKA NVRAM
Using 672 bytes
!
version 16.6.4
no service timestamps log datetime msec
no service timestamps debug datetime msec
no service password-encryption
!
hostname Router
!
!
!
!
!
!
!
!
no ip cef
no ipv6 cef
!
!
!
!
!
!
!
!
!
!
!
!
spanning-tree mode pvst
!
!
!
!
!
!
interface GigabitEthernet0/0/0
no ip address
duplex auto
speed auto
shutdown
!
interface GigabitEthernet0/0/1
no ip address
duplex auto
speed auto
shutdown
!
interface GigabitEthernet0/0/2
no ip address
duplex auto
speed auto
shutdown
!
interface Vlan1
no ip address
shutdown
!
ip classless
!
ip flow-export version 9
!
!
!
!
!
!
!
!
line con 0
!
line aux 0
!
line vty 0 4
login
line vty 5 15
login
!
!
!
end
to copy a running config to NVRAM:
router# copy running-config startup-config
to erase NVRAM:
router# erase startup-config
router# erase startup-config
Erasing the nvram filesystem will remove all configuration files! Continue? [confirm]
[OK]
Erase of nvram: complete
%SYS-7-NV_BLOCK_INIT: Initialized the geometry of nvram
router# show startup-config
startup-config is not present
router# reload
Proceed with reload? [confirm]
[output cut]
Would you like to enter the initial configuration dialog? [yes/no]:
Hands-on Lab 6.5 Setting Passwords
add a secret password
router(config)#
enable secret 1234
remove the secret password
router(config)#
no enable secret
Note youre not prompted for the secret, since you already had to provide
it in order to enter conf mode
add a regular password
router(config)#
enable password 4321
Can coexist with the secret password, but the two passwords must be different
----------------------------------------------------------------------
add password for Telnet aka VTY
router(config)#
line vty 0 15
16 virtual telnet lines on this router
We can set the whole range, a portion of the range, or a single line
router(config)#
login activate authentication
router(config)#
password telnet123
----------------------------------------------------------------------
add password for Auxiliary
router(config)#
line aux 0 there's only sone aux line
router(config)#
login activate authentication
router(config)#
password aux123
----------------------------------------------------------------------
add password for Console
router(config)#
line console 0 there's only one console line
router(config)#
login activate authentication
router(config)#
password console123
router(config)#
exec-timeout 0 0 min/sec
stop the console from timing out and logging you out
router(config)#
logging synchronous
dont overwrite input commands with console messages
Hands-on Lab 6.6 Setting the Hostname, Descriptions, IP Address, and Clock Rate
set router name
router(config)#
hostname routerA
------------------------------------------
set motd banner
routerA(config)#
banner ?
login Set login banner
motd Set Message of the Day banner
router(config)#
banner motd #
Enter TEXT message. End with the character '#'.
welcome to the router #
router(config)#
------------------------------------------
remove the banner
router(config)#
no banner motd
------------------------------------------
set login banner
router(config)#
banner login #
Enter TEXT message. End with the character '#'.
please login now #
router(config)#
------------------------------------------
add an IP address to an interface
router(config)#
do show interfaces use "do" to enable this command within config mode
GigabitEthernet0/0/0 is administratively down, line protocol is down (disabled)
---cut---
GigabitEthernet0/0/1 is administratively down, line protocol is down (disabled)
---cut---
GigabitEthernet0/0/2 is administratively down, line protocol is down (disabled)
---cut---
Vlan1 is administratively down, line protocol is down
router(config)#
interface g0/0/0
router(config-if)#
ip address 1.1.1.1 255.255.0.0
router(config-if)#
no shutdown
%LINK-5-CHANGED: Interface GigabitEthernet0/0/0, changed state to up
router(config-if)#
do show interfaces
GigabitEthernet0/0/0 is up, line protocol is down (disabled)
Internet address is 1.1.1.1/16
router(config-if)#
description WAN link to Miami
Chapter 6 Review Questions
1. You type show running-config and get this output:
---cut---
line console 0
Exec-timeout 1 44
Password 7 098C0BQR
Login
---cut---
What do the two numbers following the exec-timeout command mean?
minutes and seconds
2. Which connection method for connecting to a router is considered "out-of-band"?
auxiliary
The aux port can be configured to allow a modem to connect to the router.
It lets you dial up to a remote router in order to connect to the aux port if the router is down.
This method is considered "out of band" since its not connecting via "the network"
3. Which two commands are required when configuring SSH on your router?
ip domain-name name
username name password password
Example: Using SSH instead of Telnet
set your hostname, domain, and username
router(config)#
hostname Dallas
Dallas(config)#
ip domain-name Lammle.com
Dallas(config)#
username Michael password 1234
generate encryption keys
Dallas(config)#
crypto key generate rsa genral-keys modulus 1024
The name for the keys will be Michael.Lammle.com
% The key modulus size is 1024 bits
% Generating 1024 bit RSA keys, keys will be non-exportable...[ok]
*June 24 19:25:30.035: %SSH-5-ENABLED: SSH 1.99 has been enabled
enable SSH version 2
router(config)#
ssh version 2
connect to the vty lines of the router
router(config)#
line vty 0 1180
configure SSH and then Telnet as access protocols
router(config-line)#
transport input ssh telnet
4. Which command will show you wheter a DTE or a DCE cable is plugged into serial 0?
show controllers serial 0
will show whether DTE or DCE cable is connected to the interface
NOTE if it is a DTE connection you must add clocking with the
clock rate command
5. Which is a correct combination of file type and default location on a Cisco router?
IOS- flash memory
startup config- NVRAM
running config- RAM
6. You set the console password, but when you display the configuration, the password doesn't show up;
it looks like this:
[output cut]
line console 0
Exec-timeout 1 44
Password 7 098C0BQR
Login
[output cut]
What command would configure the password to be stored this way?
service password-encryption
7. Which command will configure all the default VTY ports on a router?
from global config mode:
line vty 0 4
will set all 5 default lines
8. Which command set the secret password to Cisco?
enable secret Cisco
9. If you wanted to see a message when logging into the router, which command would you use?
MOTD
10. Which prompt indicate that the router is currently in priviliged mode?
router#
11. What command do you type to save the configuration stored in RAM to NVRAM?
copy running-config startup-config
12. You try to telnet into SSFRouter from router to Corp and receive this message:
Corp#telnet SFRouter
Trying SFRouter (10.0.0.1)...Open
Password required, but none set
[Connection to SFRouter closed by foreing host]
Corp#
Which command sequence will address the problem correctly?
SFRouter(config)#
line vty 0 4
SFRouter(config-line)#
password password1234
SFRouter(config-line)#
login
13. Which command will delete the contents of NVRAM on a router?
erase startup-config
14. What is the problem with an interface if you type
show interface serial 9
and receive the following message?
Serial0 is administratively down, line protocol is down
is set to 'shut' by default, fix with no shut
15. Which command displays the configurable parameters and statistics of all interfaces on a router?
show interfaces
16. If you delete the contents of NVRAM and reboot the router, what mode will you be in?
setup mode
--- System Configuration Dialog ---
Would you like to enter the initial configuration dialog? [yes/no]:
17. You type the following command into the router and receive the following output:
Router#show serial 0/0
^
% Invalid input detected at '^' marker.
show interface serial 0/0
18. You type Router#sh ru and receive a % ambiguous command error.
Why did you receive this error?
not specific enough- there is more than one possible
show
command that starts with
ru
19. Which of the following commands will display the current
IP addressing and the layer 1 and 2 status of an interface?
show interfaces
GigabitEthernet0/0/0 is up, line protocol is down (disabled)
Hardware is ISR4331-3x1GE, address is 000d.bd45.db01 (bia 000d.bd45.db01)
Internet address is 1.1.1.1/16
MTU 1500 bytes, BW 1000000 Kbit, DLY 10 usec,
reliability 255/255, txload 1/255, rxload 1/255
Encapsulation ARPA, loopback not set
Keepalive not supported
Half Duplex, 1000Mbps, link type is auto, media type is Auto Select
output flow-control is on, input flow-control is on
ARP type: ARPA, ARP Timeout 04:00:00,
Last input 00:00:08, output 00:00:05, output hang never
Last clearing of "show interface" counters never
Input queue: 0/375/0 (size/max/drops); Total output drops: 0
Queueing strategy: fifo
Output queue :0/40 (size/max)
5 minute input rate 0 bits/sec, 0 packets/sec
5 minute output rate 0 bits/sec, 0 packets/sec
0 packets input, 0 bytes, 0 no buffer
Received 0 broadcasts (0 IP multicasts)
0 runts, 0 giants, 0 throttles
0 input errors, 0 CRC, 0 frame, 0 overrun, 0 ignored
0 watchdog, 1017 multicast, 0 pause input
0 input packets with dribble condition detected
0 packets output, 0 bytes, 0 underruns
0 output errors, 0 collisions, 1 interface resets
0 unknown protocol drops
0 babbles, 0 late collision, 0 deferred
0 lost carrier, 0 no carrier
0 output buffer failures, 0 output buffers swapped out
GigabitEthernet0/0/1 is administratively down, line protocol is down (disabled)
Hardware is ISR4331-3x1GE, address is 000d.bd45.db02 (bia 000d.bd45.db02)
MTU 1500 bytes, BW 1000000 Kbit, DLY 10 usec,
reliability 255/255, txload 1/255, rxload 1/255
Encapsulation ARPA, loopback not set
Keepalive not supported
output flow-control is on, input flow-control is on
ARP type: ARPA, ARP Timeout 04:00:00,
Last input 00:00:08, output 00:00:05, output hang never
Last clearing of "show interface" counters never
Input queue: 0/375/0 (size/max/drops); Total output drops: 0
Queueing strategy: fifo
Output queue :0/40 (size/max)
5 minute input rate 0 bits/sec, 0 packets/sec
5 minute output rate 0 bits/sec, 0 packets/sec
0 packets input, 0 bytes, 0 no buffer
Received 0 broadcasts (0 IP multicasts)
0 runts, 0 giants, 0 throttles
0 input errors, 0 CRC, 0 frame, 0 overrun, 0 ignored
0 watchdog, 1017 multicast, 0 pause input
0 input packets with dribble condition detected
0 packets output, 0 bytes, 0 underruns
0 output errors, 0 collisions, 1 interface resets
0 unknown protocol drops
0 babbles, 0 late collision, 0 deferred
0 lost carrier, 0 no carrier
0 output buffer failures, 0 output buffers swapped out
GigabitEthernet0/0/2 is administratively down, line protocol is down (disabled)
Hardware is ISR4331-3x1GE, address is 000d.bd45.db03 (bia 000d.bd45.db03)
MTU 1500 bytes, BW 1000000 Kbit, DLY 10 usec,
reliability 255/255, txload 1/255, rxload 1/255
Encapsulation ARPA, loopback not set
Keepalive not supported
Half Duplex, 1000Mbps, link type is auto, media type is unknown media type
output flow-control is on, input flow-control is on
ARP type: ARPA, ARP Timeout 04:00:00,
Last input 00:00:08, output 00:00:05, output hang never
Last clearing of "show interface" counters never
Input queue: 0/375/0 (size/max/drops); Total output drops: 0
Queueing strategy: fifo
Output queue :0/40 (size/max)
5 minute input rate 0 bits/sec, 0 packets/sec
5 minute output rate 0 bits/sec, 0 packets/sec
0 packets input, 0 bytes, 0 no buffer
Received 0 broadcasts (0 IP multicasts)
0 runts, 0 giants, 0 throttles
0 input errors, 0 CRC, 0 frame, 0 overrun, 0 ignored
0 watchdog, 1017 multicast, 0 pause input
0 input packets with dribble condition detected
0 packets output, 0 bytes, 0 underruns
0 output errors, 0 collisions, 1 interface resets
0 unknown protocol drops
0 babbles, 0 late collision, 0 deferred
0 lost carrier, 0 no carrier
0 output buffer failures, 0 output buffers swapped out
Vlan1 is administratively down, line protocol is down
Hardware is CPU Interface, address is 00d0.9715.9967 (bia 00d0.9715.9967)
MTU 1500 bytes, BW 100000 Kbit, DLY 1000000 usec,
reliability 255/255, txload 1/255, rxload 1/255
Encapsulation ARPA, loopback not set
ARP type: ARPA, ARP Timeout 04:00:00
Last input 21:40:21, output never, output hang never
Last clearing of "show interface" counters never
Input queue: 0/75/0/0 (size/max/drops/flushes); Total output drops: 0
Queueing strategy: fifo
Output queue: 0/40 (size/max)
5 minute input rate 0 bits/sec, 0 packets/sec
5 minute output rate 0 bits/sec, 0 packets/sec
1682 packets input, 530955 bytes, 0 no buffer
Received 0 broadcasts (0 IP multicast)
0 runts, 0 giants, 0 throttles
0 input errors, 0 CRC, 0 frame, 0 overrun, 0 ignored
563859 packets output, 0 bytes, 0 underruns
0 output errors, 23 interface resets
0 output buffer failures, 0 output buffers swapped out
show ip interface
GigabitEthernet0/0/0 is up, line protocol is down (disabled)
Internet address is 1.1.1.1/16
Broadcast address is 255.255.255.255
Address determined by setup command
MTU is 1500 bytes
Helper address is not set
Directed broadcast forwarding is disabled
Outgoing access list is not set
Inbound access list is not set
Proxy ARP is enabled
Security level is default
Split horizon is enabled
ICMP redirects are always sent
ICMP unreachables are always sent
ICMP mask replies are never sent
IP fast switching is disabled
IP fast switching on the same interface is disabled
IP Flow switching is disabled
IP Fast switching turbo vector
IP multicast fast switching is disabled
IP multicast distributed fast switching is disabled
Router Discovery is disabled
IP output packet accounting is disabled
IP access violation accounting is disabled
TCP/IP header compression is disabled
RTP/IP header compression is disabled
Probe proxy name replies are disabled
Policy routing is disabled
Network address translation is disabled
BGP Policy Mapping is disabled
Input features: MCI Check
WCCP Redirect outbound is disabled
WCCP Redirect inbound is disabled
WCCP Redirect exclude is disabled
GigabitEthernet0/0/1 is administratively down, line protocol is down (disabled)
Internet protocol processing disabled
GigabitEthernet0/0/2 is administratively down, line protocol is down (disabled)
Internet protocol processing disabled
Vlan1 is administratively down, line protocol is down
Internet protocol processing disabled
20. At which layer of the OSI model would you assume the problem is if you type
show interface serial 1
and receive the following message?
Serial 1 is down, line protocol is down
physical
if you see both interface and protocal down, it's physical
if you see serial1 is up but line protocol down, its data link- data-link keepalives are not being sent from the remote end
END CHAPTER 6
15 hours 1-15 thru 1-19-22
original total hours 63
2.5 hours review 12-21-22
review total hours 13.5
book page 274/822
Chapter 7 Notes - Managing a Cisco Internetwork
notes
Configuration Register
16 bits / 2 bytes... bit values from 15 to 0
uses Hexadecimal nibbles
Chapter 7 Exam Essentials - Managing a Cisco Internetwork
1. Define the Cisco router componenets
ROM
- used to start and maintain the router. Holds bootstrap, POST, mini-IOS
bootstrap
- stored in the microcode of the ROM. Finds where the IOS program is located and loads the file.
POST
- stored in the microcode of the ROM. Used to check the basic funtionality and determine which interfaces are present
ROM monitor
- stored in the microcode of the ROM. Used for manufacturing, testing, and troubleshooting
mini-IOS
- Called the RXBOOT or 'bootloader'. It's a small OS in ROM that can be used to bring up an interface and load a Cisco IOS into flash memory
-----------------------------------------------------------------------------------------------------------------------
flash memory
- EEPROM- default location of the IOS
NVRAM
-holds the router/switch configuration
not erased when the device is reloaded
configuration register
- controls how the router boots up
Tells the router to load the IOS from flash memory as well as to load the configuration from NVRAM
RAM
- used to hold packet buffers, ARP cache, routing tables and the data structures that allow the router to function.
running-config is stored in RAM
routers expand the IOS from flash into RAM at boot
2. Identify the steps in the router boot sequence
POST
bootstrap
load the IOS from flash into RAM
load the configuration file from NVRAM into RAM
running-config and the IOS are both now running in RAM
3. Understand configuration register commands and settings
0x2102 default- find the boot sequence in NVRAM
0x2101 boot from ROM
0x2142 do not load the startup-config in NVRAM. Used for password recovery
4.Perform password recovery
NOTE - this requires physical access to reboot the router
The default configuration register value is 0x2102 which tells the router to load a config stored
in NVRAM(startup-config).
To recover a password, we need to change the config register value to 0x2142 which tells the router to ignore the VRAM contents and load a 'non configured' OS.
"configurations" can be defined as any changes we make to the device: hostname, passwords, interfaces, etc
For this demo, our 4331 router is configured with the hostname 4331 and the password 1234
4331(config)#
enable secret 1234
4331#
copy run start
Destination filename [startup-config]?
Building configuration...
[OK]
Step 1. Bounce the router, then interrupt the boot sequence by performing a break.
Initializing Hardware ...
Checking for PCIe device presence...done
System integrity status: 0x610
Rom image verified correctly
System Bootstrap, Version 16.7(3r), RELEASE SOFTWARE
Copyright (c) 1994-2018 by cisco Systems, Inc.
Current image running: Boot ROM0
Last reset cause: LocalSoft
Cisco ISR4331/K9 platform with 4194304 Kbytes of main memory
no valid BOOT image found
Final autoboot attempt from default boot device...
Located isr4300-universalk9.16.06.04.SPA.bin
###############################################################
CTRL+BREAK
monitor: command "boot" aborted due to user interrupt
rommon 1 >
Step 2. We're given a ROM MONITOR prompt which allows us to change the configuration register (Cisco ISR/2600 Series commands).
rommon 1 >
confreg 0x2142
rommon 1 >
reset must reset or power cycle router to apply the change
system will ask if you want Setup Mode - that is the the generic startup message,
since we are bypassing the startup configuration. Our answer is no.--- System Configuration Dialog ---
Would you like to enter the initial configuration dialog? [yes/no]:
N + Enter
we now have full access to this non-configured OS. We can enter priviliged mode with no password.
Router>
enable
Router#
show version
Cisco IOS Software [Everest], ISR Software (X86_64_LINUX_IOSD-UNIVERSALK9-M), Version 16.6.4,RELEASE SOFTWARE (fc3)
[cut]
Configuration register is 0x2142
this verifies that our configs are not in use (no hostname in the prompt) and our config register has been changed to 2142
HERE IS THE KEY-
we are going to restore the configuration by copying the "startup-config"
into our live environment AKA the "running-config"
Router#
copy startup-config running-config
Destination filename [running-config]? Enter
695 bytes copied in 0.416 secs (1670 bytes/sec)
4331#
%SYS-5-CONFIG_I: Configured from console by console
we get our old prompt back:
4331#
Note that we DO NOT know the password required to enter privliged mode that we are currently inside of!
if you exit this prompt back out to user mode, you will not be able to get back in without the password.
We entered privileged mode from within the generic configuration. Then inserted our saved configuration 'beneath' our prompt.
This action does not kick you out of priv. mode, which will allow us to RESET the password for our saved configuration.
set the new password
4331(config)#
enable secret 0000
set the config register back to default, to point back to NVRAM on the next reboot
(you can do this from global config mode as well as rommon mode)
4331(config)#
config-register 0x2102
4331#
show version
[cut]
Configuration register is 0x2142 (will be 0x2102 at next reload)
now we can save the config with the updated password.
Two ways to do it-
4331#
write
Building configuration...
[OK]
OR
4331#
copy running-config startup-config
Destination filename [startup-config]?
Building configuration...
[OK]
reload the router and your new password will be saved into your config
4331#
reload
this feature is helpful since Cisco equipment tends to run for long stretches of time (years) and the passwords get forgotten.
Thank you to Jeremy Cioara for help on this topic
5. Back up an IOS image
we can copy a router's configuration to a TFTP server with either of these commands:
Router#
copy running-config tftp
Router#
copy startup-config tftp
to verify either of the configs before backup, we can use these commands:
Router#
show running-config
Router#
show startup-config
6. Restore or upgrade an IOS image - note we are talking about the IOS itself, not the 'configuration'
We will download the IOS file from TFTP server to flash memory on the router. Command requires the IP of the TFTP host and the filename
Before we begin we must make sure the IOS file is in the default TFTP directory on the host.
The command will not ask you where the file is on the host....
Router#
copy tftp flash
Address or name of remote host []? 1.1.1.2
Source filename []? c2800nm-advsecurityk9-mz.124.12.bin
Destination filename[c2800nm-advsecurityk9-mz.124.12.bin]? ENTER
%Warning this is a file already existing with this name
Do you want to over write [confirm] ENTER
Accessing tftp://1.1.1.2/c2800nm-advsecurityk9-mz.124-12.bin...
Loading c2800nm-advsecurityk9-mz.124-12.bin from 1.1.1.2 (via FastEthernet0/0): !!!!!!!!!!!!!!!!
!!!!!!!!!!!!!!!!!!!!!!!!!!
[OK - 21710744 bytes]
21710744 bytes copied in 82.880 secs (261954 bytes/sec)
Router#
to restore configuration:
restore from startup-config:
Router#
copy startup-config running-config
or we can restore from a backup on TFTP server
Router#
copy tftp running-config
Address or name of remote host []? 1.1.1.2
Source filename []? todd-confg
Destination filename[running-config?] ENTER
Accessing tftp://1.1.1.2/todd-confg...
Loading todd-confg from 1.1.12 (civa FastEthernet0/0): !
[OK - 776 bytes]
776 bytes copied in 9.212 secs (84 bytes/sec)
Router#
*Jan 23 12:40:00.000: %SYS-5-CONFIG_I: Configured from tftp://1.1.1.2/todd-confg by console
Router#
7. Describe best practices to prepare to back up an IOS image to a network server
Ensure you can acccess the network server, and there is adequate storage space.
Verify the file naming and path requirements
have the source IOS file in the default TFTP directory
8. Save the configuration of a router
Router#
copy running-config startup-config
9. Erase the configuration of a router
Router#
erase startup-config
10. Understand and use the Cisco IFS file system management commands
IFS = IOS File System
UNIX Based
dir
show files in a directory. Requires privliged mode. If not path is given as argument, you'll see the directory of 'flash' root.
NOTE the file paths use a URL format
R1#
dir
Directory of flash:/
3 -rw- 486899872 <no date> isr4300-universalk9.16.06.04.SPA.bin
2 -rw- 28282 <no date> sigdef-category.xml
1 -rw- 227537 <no date> sigdef-default.xml
3249049600 bytes total (2761893909 bytes free)
-------------------------------------------------------------------------------------------------------
copy
often used to backup, restore, or ugprade the IOS
first arg = source
second arg = destination
R1#
copy
source
destination
-------------------------------------------------------------------------------------------------------
more
display a text file
-------------------------------------------------------------------------------------------------------
show file
display a text file
-------------------------------------------------------------------------------------------------------
delete
remote file (may also need to use SQUEEZE to free up the space)
-------------------------------------------------------------------------------------------------------
erase/format
may delete flash drive depending on system
-------------------------------------------------------------------------------------------------------
cd/pwd
change directory / print working directory
-------------------------------------------------------------------------------------------------------
mkdir/rmdir
create / delete directories
11. Describe the value of CDP
Cisco Discovery Protocol - helps to document / troubleshoot the network
See lab 7.4
12. List the information provided by the output of
show cdp neighbors
device ID
local interface
holdtime
capabilility
platform
port ID (remote interface)
13. Understand how to establish a Telnet session with multiple routers simultaneously
Press Ctrl+Shift+6 then x to exit a telnet session without closing it
14. Identify current Telnet sessions
R1#
show sessions
15. Build a static host table on a router
R1#
ip host
host_name
ip_address
manually assigning an IP to a host name. You can apply multiple IP's to one host entry
see lab 7.6
16. Verify the host table on a router
R1#
show hosts
17. Describe the function of the ping command
Packet Internet Groper uses ICMP echo requests and replies to verify an active IP address on a network
18. Ping a vaild host ID from the correct prompt
R1#
ping 1.1.1.1
Note PING works from user or privliged mode but NOT config mode
Chapter 7 Written Lab 7.1 - IOS Management
TFTP Server Setup - network layout is not from book- I created this network to help demo the written lab
TFTP server is already created and switched on by default within the 'Server' object
Router Configuration
R1(config)#
int g0/0/1
R1(config-if)#
ip address 10.1.1.4 255.255.255.0
R1(config-if)#
no shutdown
%LINK-5-CHANGED: Interface GigabitEthernet0/0/1, changed state to up
%LINEPROTO-5-UPDOWN: Line protocol on Interface GigabitEthernet0/0/1, changed state to up
r1(config-if)#
do show ip int brief
Interface IP-Address OK? Method Status Protocol
GigabitEthernet0/0/0 unassigned YES manual administratively down down
GigabitEthernet0/0/1 192.1.1.4 YES NVRAM up up
GigabitEthernet0/0/2 unassigned YES NVRAM administratively down down
Vlan1 unassigned YES NVRAM administratively down down
Switch Configuration
SW1(config)#
int f0/1
SW1(config-if)#
no shutdown
%LINK-5-CHANGED: Interface FastEthernet0/1, changed state to up
%LINEPROTO-5-UPDOWN: Line protocol on Interface FastEthernet0/1, changed state to up
SW1(config-if)#
int f0/2
SW1(config-if)#
no shutdown
%LINK-5-CHANGED: Interface FastEthernet0/2, changed state to up
%LINEPROTO-5-UPDOWN: Line protocol on Interface FastEthernet0/2, changed state to up
Test connectivity to the server
R1#
ping 192.1.1.3
Type escape sequence to abort.
Sending 5, 100-byte ICMP Echos to 192.1.1.3, timeout is 2 seconds:
.!!!!
Success rate is 80 percent (4/5), round-trip min/avg/max = 0/1/6 ms
Find the name of the Router flash file
R1#
show flash
System flash directory:
File Length Name/status
3 486899872isr4300-universalk9.16.06.04.SPA.bin
2 28282 sigdef-category.xml
1 227537 sigdef-default.xml
[487155691 bytes used, 2761893909 available, 3249049600 total]
3.17338e+06K bytes of processor board System flash (Read/Write)
we need to paste that filename into our copy command below
1. command to copy a Cisco IOS to a TFTP server?
R1#
copy flash tftp
Source filename []? isr4300-universalk9.16.06.04.SPA.bin
Address or name of remote host []? 192.1.1.3
Destination filename [isr4300-universalk9.16.06.04.SPA.bin]? ENTER
Writing isr4300-universalk9.16.06.04.SPA.bin...!!!!!!!!!!!!!!!!
!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!
[OK - 486899872 bytes]
486899872 bytes copied in 12.364 secs (126865 bytes/sec)
the file appears on our server
2. command to copy a Cisco startup-config file to a TFTP server?
R1#
copy running-config tftp
Address or name of remote host []? 192.1.1.3
Destination filename [r1-confg]? ENTER
Writing running-config.....!!
[OK - 707 bytes]
707 bytes copied in 3 secs (235 bytes/sec)
the file appears on our server
OR
R1#
copy startup-config tftp
3. command to copy the startup-config file to DRAM?
R1#
copy startup-config running-config
the running configuration exists in DRAM
4. What is an older command that you can use to copy the startup-config file to DRAM?
R1#
config mem
(not supported by packet tracer)
5. What command can you use to see the neighbor router's IP address from your router prompt?
R1#
show cdp neighbor detail
OR
R1#
show cdp entry *
6. What command to see the hostname, local interface, platform, and remote port of a neighbor router?
R1#
show cdp neighbor
7. What keystrokes can you use to telnet into multiple devices simultaneously?
Ctrl + Shift + 6, then X
8. What command will show you your active Telnet connections to neighbor and remote devices?
R1#
show sessions
9. What command can you use to upgrade a Cisco IOS?
R1#
copy tftp flash
10. What command can you use to merge a backup configuration with the configuration in RAM?
R1#
copy tftp run
OR
R1#
copy start run
RAM = running configuration
Chapter 7 Written Lab 7.2 - Router Memory
Identify the location in a router where each of the files is stored by default:
1. Cisco IOS
flash
2. Bootstrap
ROM
3. Startup configuration
NVRAM
4. POST
ROM
5. Running configuration
RAM
6. ARP cache
RAM
7. Mini IOS
ROM
8. ROM Monitor
ROM
9. Routing tables
RAM
10. packet buffers
RAM
****dont make the mistake of thinking arp cache, routing tables, packet buffers, are stored somewhere other than RAM
they are considered part of running-config which exists in RAM
Chapter 7 Hands-on Labs
To complete these labs, we are going to need three routers and one TFTP server.
Here is the topology:
Server Configuration
ipv4 address: 193.1.1.2
subnet mask: 255.255.255.248
default gateway: 193.1.1.1
Switch Configuration
SW1#
interface range f0/1-2
SW1(config-if-range)#
no shut
Router Configurations
R1(config)#
int g0/0/0
R1(config)#
ip addr 193.1.1.9 255.255.255.248
R1(config)#
no shut
R1(config)#
int g0/0/1
R1(config)#
ip addr 193.1.1.1 255.255.255.248
R1(config)#
no shut
the server's default gateway
R2(config)#
int g0/0/0
R2(config)#
ip addr 193.1.1.10 255.255.255.248
R2(config)#
no shut
R2(config)#
int g0/0/1
R2(config)#
ip addr 193.1.1.17 255.255.255.248
R2(config)#
no shut
R3(config)#
int g0/0/0
R3(config)#
ip addr 193.1.1.18 255.255.255.248
R3(config)#
no shut
the segment between R1 and the server
network 193.1.1.0/29
block of 8
hosts .1, .2
the segment between R1 and R2
network 193.1.1.8/29
block of 8
hosts .9 , .10
the segment between the R2 and R3
network 193.1.1.16/29
block of 8
hosts .17 , .18
THIS IS INCORRECT!!!!
I have misunderstood the instructions.
the problem with this topology is that packets cannot pass through the routers. We dont have any ROUTING setup. ROUTING is covered in the next chapter.
For these labs, we dont need routing, but we need multiple routers to demo telnet and CDP. Here are the instructions:
my mistake was not putting all router interfaces in the same subnet. I tried to do this initially, but it wouldnt work because I had the routers linked together rather than connected by a switch.
The instructions say:
"Your PC and the router(s) are connected together with a switch"
this is the part I missed. The pc and all router interfaces should be on the same switch and the same network
Here is the corrected topology
Server Configuration
ipv4 address: 193.1.1.4
subnet mask: 255.255.255.248
default gateway: 193.1.1.1
Switch Configuration
SW1#
interface range f0/1-4
SW1(config-if-range)#
no shut
Router Configurations
R1(config)#
int g0/0/0
R1(config)#
ip addr 193.1.1.1 255.255.255.248
R1(config)#
no shut
the server's default gateway
R2(config)#
int g0/0/0
R2(config)#
ip addr 193.1.1.2 255.255.255.248
R2(config)#
no shut
R3(config)#
int g0/0/0
R3(config)#
ip addr 193.1.1.3 255.255.255.248
R3(config)#
no shut
Chapter 7 Hands-on Lab 7.1 Backing up your router IOS
1. verify connection to the server
R1#
ping 193.1.1.1
Type escape sequence to abort.
Sending 5, 100-byte ICMP Echos to 193.1.1.2, timeout is 2 seconds:
.!!!!
Success rate is 80 percent (4/5), round-trip min/avg/max = 0/1/5 ms
2. show contents of flash memory
R1#
show flash
System flash directory:
File Length Name/status
3 486899872isr4300-universalk9.16.06.04.SPA.bin
2 28282 sigdef-category.xml
1 227537 sigdef-default.xml
[487155691 bytes used, 2761893909 available, 3249049600 total]
3.17338e+06K bytes of processor board System flash (Read/Write)
show flash gives ALL of the files in flash memory
show version gives the current running file
3. show the IOS currently running
R1#
show version
Cisco IOS XE Software, Version 03.16.05.S - Extended Support Release
[cut]
ROM: IOS-XE ROMMON
Router uptime is 9 minutes, 39 seconds
Uptime for this control processor is 9 minutes, 39 seconds
System returned to ROM by power-on
System image file is "bootflash:/isr4300-universalk9.03.16.05.S.155-3.S5-ext.SPA.bin"
Last reload reason: PowerOn
[cut]
note that the file that is currently running is NOT located in the flash storage!!!
4. backup IOS from router to server
R1#
copy flash tftp
Source filename []?isr4300-universalk9.16.06.04.SPA.bin
Address or name of remote host []? 193.1.1.4
Destination filename [isr4300-universalk9.16.06.04.SPA.bin]? ENTER
Writing isr4300-universalk9.16.06.04.SPA.bin...!!!!!!!!!!!!!!!
[OK - 486899872 bytes]
486899872 bytes copied in 12.526 secs (125224 bytes/sec)
Chapter 7 Hands-on Lab 7.2 Upgrading or restoring your router IOS
1. verify connection to the server
R1#
ping 193.1.1.4
Type escape sequence to abort.
Sending 5, 100-byte ICMP Echos to 193.1.1.2, timeout is 2 seconds:
!!!!!
Success rate is 100 percent (5/5), round-trip min/avg/max = 0/0/1 ms
2. copy from tftp sever to flash
R1#
copy tftp flash TFTP comes first in the command since we are pulling from TFTP server.
In this command, remot host address is required before file name
Address or name of remote host []? 193.1.1.4
Source filename []?isr4300-universalk9.16.06.04.SPA.bin
Destination filename [isr4300-universalk9.16.06.04.SPA.bin]? ENTER
%Warning:There is a file already existing with this name
Do you want to over write? [confirm]
Accessing tftp://193.1.1.4/isr4300-universalk9.16.06.04.SPA-12-23-22...
Loading isr4300-universalk9.16.06.04.SPA-12-23-22.bin from 193.1.1.4: !!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!
[OK - 486899872 bytes]
486899872 bytes copied in 12.785 secs (122688 bytes/sec)
Chapter 7 Hands-on Lab 7.3 Backing up the router configuration
1. verify connection to the server
R1#
ping 193.1.1.2
Type escape sequence to abort.
Sending 5, 100-byte ICMP Echos to 193.1.1.4, timeout is 2 seconds:
!!!!!
Success rate is 100 percent (5/5), round-trip min/avg/max = 0/0/1 ms
2. copy running-confing to server
R1#
copy run tftp
Address or name of remote host []? 193.1.1.4
Destination filename [R1-confg]?ENTER "R1-confg" is the default name
Writing running-config...!!
[OK - 668 bytes]
668 bytes copied in 0.004 secs (167000 bytes/sec)
Chapter 7 Hands-on Lab 7.4 Using the Cisco Discovery Protocol (CDP)
R1#
show cdp
Global CDP information:
Sending CDP packets every 60 seconds
Sending a holdtime value of 180 seconds
Sending CDPv2 advertisements is enabled
R1#
show cdp interface
Vlan1 is administratively down, line protocol is down
Sending CDP packets every 60 seconds
Holdtime is 180 seconds
GigabitEthernet0/0/0 is up, line protocol is up
Sending CDP packets every 60 seconds
Holdtime is 180 seconds
GigabitEthernet0/0/1 is administratively down, line protocol is down
Sending CDP packets every 60 seconds
Holdtime is 180 seconds
GigabitEthernet0/0/2 is administratively down, line protocol is down
Sending CDP packets every 60 seconds
Holdtime is 180 seconds
R1#
show cdp entry *
Device ID: SW1
Entry address(es):
Platform: cisco 2960, Capabilities: Switch
Interface: GigabitEthernet0/0/0, Port ID (outgoing port): FastEthernet0/1
NOTE g0/0/0 is the outgoing port on this router, F0/1 is the port on the switch at other end
Holdtime: 157
Version :
Cisco IOS Software, C2960 Software (C2960-LANBASEK9-M), Version 15.0(2)SE4, RELEASE SOFTWARE (fc1)
Technical Support: http://www.cisco.com/techsupport
Copyright (c) 1986-2013 by Cisco Systems, Inc.
Compiled Wed 26-Jun-13 02:49 by mnguyen
advertisement version: 2
Duplex: full
R1#
show cdp entry neighbors
[no output]
R1#
show cdp neighbors detail
Device ID: SW1
Entry address(es):
Platform: cisco 2960, Capabilities: Switch
Interface: GigabitEthernet0/0/0, Port ID (outgoing port): FastEthernet0/1
Holdtime: 178
Version :
Cisco IOS Software, C2960 Software (C2960-LANBASEK9-M), Version 15.0(2)SE4, RELEASE SOFTWARE (fc1)
Technical Support: http://www.cisco.com/techsupport
Copyright (c) 1986-2013 by Cisco Systems, Inc.
Compiled Wed 26-Jun-13 02:49 by mnguyen
advertisement version: 2
Duplex: full
Chapter 7 Hands-on Lab 7.5 Using Telnet
enable telnet on R2 and set password
R2(config)#
line vty 0 15
R2(config-line)#
password telnet
R2(config-line)#
login
enable telnet on R3 and set password
R3(config)#
line vty 0 15
R3(config-line)#
password telnet
R3(config-line)#
login
note that the result of this command on each router, by default,
is to present all 15 lines in TWO SEPERATE chunks: 0-4 and 5-15
R3#
show run
[cut]
!
!
!
line con 0
!
line aux 0
!
line vty 0 4
password telnet
login
line vty 5 15
password telnet
login
!
!
!
end
--------------------------------------------------------------------------------
connect to R2 from R1
R1#
telnet 193.1.1.2
Trying 193.1.1..2 ...Open
User Access Verification
Password: telnet
prompt changes to R2 to indicate we are remoted in
R2>
exit the session
ctrl + shift + 6, x
prompt changes back to R1
R1#
--------------------------------------------------------------------------------
connect to R3 from R1
R1#
193.1.1.3 note that the word 'telnet' is not required bc we are still in telnet mode
Trying 193.1.1..3 ...Open
User Access Verification
Password: telnet
prompt changes to R3 to indicate we are remoted in
R3>
exit the session
ctrl + shift + 6, x
prompt changes back to R1
R1#
--------------------------------------------------------------------------------
We have exited the sessions, but they are still open
R1#
show sessions
Conn Host Address Byte Idle Conn Name
1 193.1.1.2 193.1.1.2 0 0 193.1.1.2
* 2 193.1.1.3 193.1.1.3 0 0 193.1.1.3
two telnet sessions- notice that the 'conn number' doesnt correspond to ip address in any way.
R1#
show users
Line User Host(s) Idle Location
* 0 con 0 193.1.1.2 00:00:03
193.1.1.3 00:00:43
this is saying one user is on this router, with two outbound connections (but it isnt showing that they are vty connections)
... they must both be considered 'console' connections outbound and are not considered 'vty' until they are received inbound
the asterisk means something different here than above... doesnt mean default(most recent)session... what does it mean?
back to R2
R2#
show users
Line User Host(s) Idle Location
* 4 vty 0 idle 00:00:00 193.1.1.1
Interface User Mode Idle Peer Address
this is saying that there is one (unnamed) user remoted in via line vty 4
back to R3
R3#
show users
Line User Host(s) Idle Location
* 4 vty 0 idle 00:00:00 193.1.1.1
Interface User Mode Idle Peer Address
this is saying that there is one (unnamed) user remoted in via line vty 4
-------------------------------------------------------------------------------------
Important Considerations:
-
asterisk indicates default session
-
when telnetting in, you will be in user mode. If there is no password already set for PRIVILEGED MODE, you will be unable to enter
-
be careful with 'exit'. it will exit the telnet session if you exit at priv. mode. Use 'disable' to leave priv mode.
-
after 'suspending' a session with ctrl+shift+6,x and youre back at your original priv. prompt, do not press enter to create line breaks-
rather than break lines as usual, the keystroke will cause this:
[Resuming connection 1 to 193.1.1.2 ... ]
prompt will sit here until you strike enter again, then you'll return to that session. What is actually happening is that
youre connecting to the 'default' telnet connection. The same behavior happens when youre at the 'show sessions' screen.
Even if you are not viewing active sessions, the enter key(twice) will connect you to the default session
-
you can use disconnect or exit to end a session
-
Ex: disconnect 1 at the show sessions screen
Chapter 7 Hands-on Lab 7.6 Resolving Hostnames
We're going to build a host table on R1 so we can connect to the other routers via hostname rather than type in the IP address
the command is ip host name arg ip arg
R1(config)#
ip host R2 193.1.1.2
R1(config)#
ip host R3 193.1.1.3
Now if we enter R2 or telnet R2 we get the telnet prompt
R1# R2
Trying 193.1.1.2 ...Open
User Access Verification
Password:
same for the PING command
R1# ping R2
Type escape sequence to abort.
Sending 5, 100-byte ICMP Echos to 193.1.1.2, timeout is 2 seconds:
!!!!!
Success rate is 100 percent (5/5), round-trip min/avg/max = 0/0/2 ms
R1#
show hosts
Default Domain is not set
Name/address lookup uses domain service
Name servers are 255.255.255.255
Codes: UN - unknown, EX - expired, OK - OK, ?? - revalidate
temp - temporary, perm - permanent
NA - Not Applicable None - Not defined
Host Port Flags Age Type Address(es)
R2 None (perm, OK) 0 IP 193.1.1.2
R3 None (perm, OK) 0 IP 193.1.1.3
R1#
telnet R2
R2>
CTRL + SHIFT + 6, X
R1#
telnet R3
R3>
CTRL + SHIFT + 6, X
R1#
show session
Conn Host Address Byte Idle Conn Name
1 R2 193.1.1.2 0 0 R2
* 2 R3 193.1.1.3 0 0 R3
Chapter 7 Review Questions
1. What does the command
confreg 0x2142
provide?
bypass startup-config, to allow password reset
2. Which command will copy the IOS to a backup host on your network?
copy flash tftp
3. You are troubleshooting a connectivity problem in your corporate network and want to isolate the problem. You suspect that a router on the route to an unreachable
network is at fault. What IOS user exec command should you issue?
traceroute
note this is not a priviliged mode command; it can be run from user mode
4. You copy a configuration from a network host to a router's RAM. The configuration looks correct, yet it is no working at all. What could the problem be?
when you perform a copy from a network host to a router, the interfaces are automatically shut down and have to be manually enabled with no shutdown
5. A network administrator wants to upgrade the IOS of a router without removing the image currently installed. What command will display the amount of memory consumed by the
current IOS image and indicate whether there is enough room available to hold both the current and new images?
show flash
6. The corporate office sends you a new router to connect, but upon connecting the console cable, you see that there is already a configuration on the router.
What should be done before a new configuration is entered in the router?
erase NVRAM and restart the router
erase startup-config
reload
7. Which command loads a new version of the Cisco IOS into a router?
copy tftp flash
8. Which command will show you the IOS version running on your router?
show version
9. What should the configuration register value be after you successfully complete the password recovery procedure and return the router to normal operation?
0x2102
10. You save the configuration on a router with the
copy running-config startup-config
command and reboot the router. The router, however, comes up with a blank configuration. What can the problem be?
wrong config register causing you to bypass startup-confing in NVRAM
11. If you want to have more than one Telnet session open at the same time, what keystroke combination would you use?
CTRL+SHIFT+6, X
12. You are unsuccessful in telnetting into a remote device, but you could telnet to the router earlier, However, you can still ping the remote device.
What can the problem be?
access control list could be filtering telnet
OR
the VTY password may not be set on the target
13. What information is displayed by the
show hosts
command?
gives info on temporary DNS entries and permanent name-to-address mappings created using the ip host command
14. Name three commands that can be used to check LAN connectivity problems on a router?
trace
show interfaces
show ip route
15. You telnet to a router and make your necessary changes; now you want to end the Telnet session. What command do you type in?
exit
16. You telnet into a remote device and type
debug ip rip
but no output from the
debug
command is seen. What could the problem be?
to see console messages through a telnet session, you must enter the command terminal monitor
17. Which command displays the configuration register setting?
show version
18. You need to gather the IP address of a remote switch that is located in Hawaii. What can you do to find the address?
show cdp neighbors detail
19. You have your laptop directly connected into a router's Ethernet port. Which are requirements for the
copy flash tftp
command to be successful?
have a TFTP server running on the laptop
laptop must have an IP on the same subnet as the router interface
give the IP address of the laptop when asked after entering the command
20. The configuration register setting of 0x2102 provides what function to a router?
points to NVRAM for startup-configuration AND boot sequence
END CHAPTER 7
26 hours 1-19 thru 1-26-22
original total hours 89
7 hours review 12-23-22
review total hours 20.5
book page 344/822
avg 15 min/page (reading and exercises/labs)
Chapter 8 Exercises
pg 374
before I begin to configure this network, I want to look closer at the HARDWARE
Todd mentions these routers:
2811 with four serial interfaces and switch module or wireless card
1841
while the book was published in 2011, both routers appear to be available in 2021 packet tracer,
but both are considered legacy as of Feb 2022.
The 2811:
The 1841:
we're going to need to understand the MODULES. What are these?
a few examples:
NM-1E is a 1-port ethernet module
NM-1FE-TX is a fast ethernet module
NM-8A/s is an Eight Port Async/Sync Network Module
HWIC-2T is a 2-port serial WAN interface card
HWIC-AP-AG-B is a wireless card
What is an "NM module"?
A network module is a software module that implements a specific
function in a network stack, such as a data link interface, a transport protocol,
or a network application.
What is a "HWIC module"?
A high-speed WAN interface card
Here is a look inside a real 2811:
Back to the requirements for our lab- Todd says the 2811 'Corp' router needs a switch module
and four serial interfaces. NOTE the book doesnt give specifics on how to create the topology in Packet Tracer.
Our Packet Tracer 2811 offers these modules:
The NM-ESW-16 appears to be the only 'switch module', so I will add that.
And the HWIC-2T is a 2-Port Serial High-Speed WAN Interface Card, providing 2 serial ports.
I will add two of these.
next: R3, which needs to be a 2811 with a wirless card. I will add the HWIC-AP-AG-B:
The HWIC-AP-AG-B module is a High-Speed WAN Interface Card providing integrated Access Point
functionality in the Cisco 1800 (Modular), Cisco 2800,
and Cisco 3800 Integrated Services Routers.
It supports Single Band 802.11b/g or Dual Band 802.11a/b/g radios.
our router hardware is in place:
and here is where we need to end up
Next we need to figure out how to connect the server farm to the switch card on R1:
if I use the auto-select cable, I get a copper crossover cable connecting at fa0/0 on the router.
Per the diagram fa0/0 should
connect to R3. I need to connect the servers to the switch card on R1.
Instead of using the auto-select cable, I'll try a straight-through cable.
Success. While the auto-select cable did not give me an option as to what port it will connect to, I did get the option when
manually applying the straight-through cable. Instead of connecting to F0/0 which would require a crossover-cable(computer to router),
I will connect to the integrated switch at port F1/0, then connect the other two servers to F1/1 and F1/2, respectively.
Also worth noting: the Physical Device diagrams in Packet Tracer do not show cables plugged into the ports.
We are relying on the labels on the logical diagram to see which cables are plugged into which ports...
As far as how we can tell what is connected from within the CLI.. I dont know right now.
Now I will connect the other routers. Here is the chart specifiying what interfaces should be used:
Router
Network Address
Interface
Address
CORP
10.1.1.0
Vlan1 (switch card)
10.1.1.1
10.1.2.0
S0/0/0
10.1.2.1
10.1.3.0
S0/0/1 (DCE)
10.1.3.1
10.1.4.0
S0/1/0
10.1.4.1
10.1.5.0
F0/0
10.1.5.1
R1
10.1.2.0
S0/0/0 (DCE)
10.1.2.2
10.1.3.0
S0/0/1
10.1.3.2
192.168.10.0
F0/0
192.168.10.1
192.168.20.0
F0/1
192.168.20.1
R2
10.1.4.0
S0/0/0 (DCE)
10.1.4.2
192.168.30.0
F0/0
192.168.30.1
192.168.40.0
F0/0
192.168.40.1
R3
10.1.5.0
F0/0
10.1.5.2
172.16.10.0
Dot11Radio0/0/0
172.16.10.1
PROBLEM
The R1 router doesnt appear to have any serial interfaces
I will add an HWIC-2T card to both R1 and R2 since the diagram calls for serial interfaces.
The HWIC-2T is a Cisco 2-Port Serial High-Speed WAN Interface Card, providing 2 serial ports.
PROBLEM
The Corp router is not showing the expected available interfaces. I need to connect R1 to the S0/0/0 interface on Corp and R2 to the S0/0/1 interface on Corp.
My Corp router is not showing those interfaces:
Solution
the placement of the cards on the router determines which interface numbers will be available.
In this case, it seems the interfaces start from the bottom right corner and increase on each slot moving clockwise. I found this out by filling all four slots on my router
which led to all interfaces being available. I then ran a card in each slot individually to isolate which interface numbers correspond to each slot:
Interestingly, while the physical slots seem to follow a 'clockwise' pattern, the list of available slots in the logical diagram does not;
We get an output of interfaces corresponding to slot 2, then 3, 1, and 4. This is a 'bottom to top' then 'left to right' pattern. Tricky.
Having said all that... I will run cards in slots 1 and 2 for this lab since we only need interfaces S0/0/0, S0/0/1, S0/1/0
The Router topology:
I'm not clear on the connections from R1 and R2 to the clients.. I assume there are switches involved.
For now I will follow the next steps in the book which
are to configure the corp router as follows:
Router(config)#
hostname Corp
Corp(config)#
enable secret todd
Corp(config)#
interface vlan 1
Corp(config-if)#
description Switch Card to Core Network
Corp(config-if)#
ip address 10.1.1.1 255.255.255.0
Corp(config-if)#
no shut
----------------------------------------------------------------------------------------------------------------
Corp(config-if)#
int f1/0
Corp(config-if)#
description Switch Port connection to WWW Server
Corp(config-if)#
no shutdown
Corp(config-if)#
int f1/1
Corp(config-if)#
description Switch Port connection to Email Server
Corp(config-if)#
no shutdown
Corp(config-if)#
int f1/2
Corp(config-if)#
description Switch Port connection to DNS Server
Corp(config-if)#
no shutdown
----------------------------------------------------------------------------------------------------------------
Corp(config-if)#
int s0/0/0
Corp(config-if)#
description 1st Connection to R1
Corp(config-if)#
ip address 10.1.2.1 255.255.255.0
Corp(config-if)#
no shut
Corp(config-if)#
int s0/0/1
Corp(config-if)#
description 2nd Connection to R1
Corp(config-if)#
ip address 10.1.3.1 255.255.255.0
Corp(config-if)#
no shut
Corp(config-if)#
int s0/1/0
Corp(config-if)#
description Connection to R2
Corp(config-if)#
ip address 10.1.4.1 255.255.255.0
Corp(config-if)#
no shut
Corp(config-if)#
int fa0/0
Corp(config-if)#
description Connection to R3
Corp(config-if)#
ip address 10.1.5.1 255.255.255.0
Corp(config-if)#
no shut
----------------------------------------------------------------------------------------------------------------
Corp(config-if)#
line con 0
Corp(config-if)#
password console
Corp(config-if)#
login
Corp(config-if)#
logging synchro
Corp(config-if)#
exec-timeout 0 0
----------------------------------------------------------------------------------------------------------------
Corp(config-if)#
line aux 0
Corp(config-if)#
password aux
Corp(config-if)#
login
Corp(config-if)#
exit
----------------------------------------------------------------------------------------------------------------
Corp(config)#
line vty ?
<1-15>Last Line number
Corp(config)#
line vty 0 15
Corp(config-if)#
password telnet
Corp(config-if)#
login
Corp(config-if)#
exit
----------------------------------------------------------------------------------------------------------------
Corp(config)#
no ip domain lookup
Corp(config)#
banner motd # This is my Corp 2811 ISR Router #
Ctrl + Z
%SYS-5-CONFIG_I: Configured from console by console
(Ctrl-Z: When in a config mode, ends the config mode and returns you to privileged EXEC mode.... same as typing exit(?))
Corp#
copy run start
Destination filename [startup-config]?
Building configuration...
[OK]
----------------------------------------------------------------------------------------------------------------
Corp#
show ip int br
Interface IP-Address OK? Method Status Protocol
FastEthernet0/0 10.1.5.1 YES manual up down
FastEthernet0/1 unassigned YES unset administratively down down
Serial0/0/0 10.1.2.1 YES manual down down
Serial0/0/1 10.1.3.1 YES manual down down
Serial0/1/0 10.1.4.1 YES manual down down
Serial0/1/1 unassigned YES unset administratively down down
FastEthernet1/0 unassigned YES unset up up
FastEthernet1/1 unassigned YES unset up up
FastEthernet1/2 unassigned YES unset up up
FastEthernet1/3 unassigned YES unset administratively down down
FastEthernet1/4 unassigned YES unset administratively down down
FastEthernet1/5 unassigned YES unset administratively down down
FastEthernet1/6 unassigned YES unset administratively down down
FastEthernet1/7 unassigned YES unset administratively down down
FastEthernet1/8 unassigned YES unset administratively down down
FastEthernet1/9 unassigned YES unset administratively down down
FastEthernet1/10 unassigned YES unset administratively down down
FastEthernet1/11 unassigned YES unset administratively down down
FastEthernet1/12 unassigned YES unset administratively down down
FastEthernet1/13 unassigned YES unset administratively down down
FastEthernet1/14 unassigned YES unset administratively down down
FastEthernet1/15 unassigned YES unset administratively down down
Vlan1 10.1.1.1 YES manual up up
----------------------------------------------------------------------------------------------------------------
Corp#
show run
Building configuration...
Current configuration : 2073 bytes
!
version 15.1
no service timestamps log datetime msec
no service timestamps debug datetime msec
no service password-encryption
!
hostname Corp
!
!
!
enable secret 5 $1$mERr$V5ujdIM9bTB/I.ipB0gkJ0
!
!
!
!
!
!
no ip cef
no ipv6 cef
!
!
!
!
license udi pid CISCO2811/K9 sn FTX1017U440-
!
!
!
!
!
!
!
!
!
no ip domain-lookup
!
!
spanning-tree mode pvst
!
!
!
!
!
!
interface FastEthernet0/0
description connection to R3
ip address 10.1.5.1 255.255.255.0
duplex auto
speed auto
!
interface FastEthernet0/1
no ip address
duplex auto
speed auto
shutdown
!
interface Serial0/0/0
description 1st connection to R1
ip address 10.1.2.1 255.255.255.0
clock rate 2000000
!
interface Serial0/0/1
description 2nd connection to R1
ip address 10.1.3.1 255.255.255.0
clock rate 2000000
!
interface Serial0/1/0
description connection to R2
ip address 10.1.4.1 255.255.255.0
!
interface Serial0/1/1
no ip address
clock rate 2000000
shutdown
!
interface FastEthernet1/0
description switch port connection to WWW Server
!
interface FastEthernet1/1
description switch port connection to Email Server
!
interface FastEthernet1/2
description switch port connection to DNS Server
!
interface FastEthernet1/3
shutdown
!
interface FastEthernet1/4
shutdown
!
interface FastEthernet1/5
shutdown
!
interface FastEthernet1/6
shutdown
!
interface FastEthernet1/7
shutdown
!
interface FastEthernet1/8
shutdown
!
interface FastEthernet1/9
shutdown
!
interface FastEthernet1/10
shutdown
!
interface FastEthernet1/11
shutdown
!
interface FastEthernet1/12
shutdown
!
interface FastEthernet1/13
shutdown
!
interface FastEthernet1/14
shutdown
!
interface FastEthernet1/15
shutdown
!
interface Vlan1
description Switch Card to Core Network
ip address 10.1.1.1 255.255.255.0
!
ip classless
!
ip flow-export version 9
!
!
!
banner motd ^C This is my Corp 2811 ISR Router ^C
!
!
!
!
!
line con 0
exec-timeout 0 0
password console
logging synchronous
login
!
line aux 0
password aux
login
!
line vty 0 4
password telnet
login
line vty 5 15
password telnet
login
!
!
!
end
-----------------------------------------------------------------------------------------------------------------------
more configurations:
R1
Router(config)#
hostname R1
R1(config)#
enable secret todd
R1(config)#
int s0/0/0
R1(config-if)#
ip address 10.1.2.2 255.255.255.0
R1(config-if)#
Decription 1st connection to corp router
R1(config-if)#
no shut
-----------------------------------------------------------------------------------------------
R1(config-if)#
int s0/0/1
R1(config-if)#
ip address 10.1.3.2 255.255.255.0
R1(config-if)#
Decription 2nd connection to corp router
R1(config-if)#
no shut
-----------------------------------------------------------------------------------------------
R1(config-if)#
int f0/0
R1(config-if)#
ip address 192.168.10.1 255.255.255.0
R1(config-if)#
Decription connection to finance
R1(config-if)#
no shut
-----------------------------------------------------------------------------------------------
R1(config-if)#
int f0/1
R1(config-if)#
ip address 192.168.20.1 255.255.255.0
R1(config-if)#
Decription connection to marketing
R1(config-if)#
no shut
R1(config-if)#
exit
-----------------------------------------------------------------------------------------------
R1(config)#
line con 0
R1(config-line)#
password console
R1(config-line)#
login
R1(config-line)#
logging synchronous
R1(config-line)#
exec-timeout 0 0
-----------------------------------------------------------------------------------------------
R1(config-line)#
line aux 0
R1(config-line)#
password aux
R1(config-line)#
login
R1(config-line)#
exit
-----------------------------------------------------------------------------------------------
R1(config)#
line vty 0 ?
<0-15> Last Line number
R1(config)#
line vty 0 807
R1(config-line)#
password telnet
R1(config-line)#
login
R1(config-line)#
banner motd # This is my R1 Router #
R1(config-line)#
exit
-----------------------------------------------------------------------------------------------
R1(config)#
no ip domain-lookup
R1(config)#
exit
R1#
copy run start
R2
Router(config)#
hostname R2
R2(config)#
enable secret todd
R2(config)#
int s0/0/0
R2(config-if)#
ip address 10.1.4.2 255.255.255.0
R2(config-if)#
description connection to corp router
R2(config-if)#
no shut
-----------------------------------------------------------------------------------------------
R2(config-if)#
int f0/0
R2(config-if)#
ip address 192.168.30.1 255.255.255.0
R2(config-if)#
description connection to sales PC
R2(config-if)#
no shut
-----------------------------------------------------------------------------------------------
R2(config-if)#
int f0/1
R2(config-if)#
ip address 192.168.40.1 255.255.255.0
R2(config-if)#
description connection to HR pc
R2(config-if)#
no shut
-----------------------------------------------------------------------------------------------
R2(config-if)#
line con 0
R2(config-line)#
password console
R2(config-line)#
login
R2(config-line)#
logging synchronous
R2(config-line)#
exec-timeout 0 0
-----------------------------------------------------------------------------------------------
R2(config-line)#
line aux 0
R2(config-line)#
password aux
R2(config-line)#
login
R2(config-line)#
exit
-----------------------------------------------------------------------------------------------
R2(config)#
line vty 0 ?
<0-15> Last Line number
R2(config)#
line vty 0 807
R2(config-line)#
password telnet
R2(config-line)#
login
R2(config-line)#
banner motd # This is my R1 Router #
R2(config-line)#
exit
-----------------------------------------------------------------------------------------------
R2(config)#
no ip domain-lookup
R2(config)#
exit
R2#
copy run start
R3
Router(config)#
hostname R3
R3(config)#
enable secret todd
R3(config)#
int f0/0
R3(config-if)#
ip address 10.1.5.2 255.255.255.0
R3(config-if)#
description connection to corp router
R3(config-if)#
no shut
-----------------------------------------------------------------------------------------------
R3(config-if)#
int dot11radio0/0/0
R3(config-if)#
ip address 172.16.10.1 255.255.255.0
R3(config-if)#
description WLAN for mobile user
R3(config-if)#
no shut
R3(config-if)#
ssid ADMIN
stuck here 2-5-22-- packet tracer isnt taking me into the config-if-ssid prompt
R3(config-if-ssid)#
guest-mode
R3(config-if-ssid)#
authentication open
R3(config-if-ssid)#
ingrastructure-ssid
R3(config-if-ssid)#
exit
-----------------------------------------------------------------------------------------------
R3(config-if)#
line con 0
R3(config-line)#
password console
R3(config-line)#
login
R3(config-line)#
logging synchronous
R3(config-line)#
exec-timeout 0 0
-----------------------------------------------------------------------------------------------
R3(config-line)#
line aux 0
R3(config-line)#
password aux
R3(config-line)#
login
R3(config-line)#
exit
-----------------------------------------------------------------------------------------------
R3(config)#
line vty 0 ?
<0-15> Last Line number
R3(config)#
line vty 0 807
R3(config-line)#
password telnet
R3(config-line)#
login
R3(config-line)#
banner motd # This is my R1 Router #
R3(config-line)#
exit
-----------------------------------------------------------------------------------------------
R3(config)#
no ip domain-lookup
R3(config)#
exit
R3#
copy run start
PROBLEM
i cant get into conf-if-ssid prompt
R3(config-if)#
ssid ADMIN
%LINK-5-CHANGED: Interface Dot11Radio0/0/0, changed state to administratively down
%LINEPROTO-5-UPDOWN: Line protocol on Interface Dot11Radio0/0/0, changed state to down
%LINK-5-CHANGED: Interface Dot11Radio0/0/0, changed state to up
%LINEPROTO-5-UPDOWN: Line protocol on Interface Dot11Radio0/0/0, changed state to up
R3(config-if)#
research led me to this thread, which is a dead end:
further research led me here:
R3(config)# global config mode
R3(config)#
dot11 ssid ADMIN
creates an SSID or lets you config an existing SSID
R3(config-ssid)#
guest-mode
R3(config-ssid)#
%LINK-5-CHANGED: Interface Dot11Radio0/0/0, changed state to administratively down
%LINEPROTO-5-UPDOWN: Line protocol on Interface Dot11Radio0/0/0, changed state to down
%LINK-5-CHANGED: Interface Dot11Radio0/0/0, changed state to up
%LINEPROTO-5-UPDOWN: Line protocol on Interface Dot11Radio0/0/0, changed state to up
R3(config-ssid)#
authentication open
R3(config-ssid)#
%LINK-5-CHANGED: Interface Dot11Radio0/0/0, changed state to administratively down
%LINEPROTO-5-UPDOWN: Line protocol on Interface Dot11Radio0/0/0, changed state to down
%LINK-5-CHANGED: Interface Dot11Radio0/0/0, changed state to up
%LINEPROTO-5-UPDOWN: Line protocol on Interface Dot11Radio0/0/0, changed state to up
R3(config-ssid)#
infrastructure-ssid
R3(config-ssid)#infrastructure-ssid
^
% Invalid input detected at '^' marker.
this command given by the book doesnt appear to be valid
R3(config-ssid)#
?
authentication authentication method
exit Exit from ssid sub mode
guest-mode guest ssid
no Negate a command or set it's defaults
wpa-psk Configure Wi-Fi Protected Access pre-shared key
back into the interface to see what the options are
R3(config-ssid)#
int dot110/0/0
R3(config-if)#
?
arp Set arp type (arpa, probe, snap) or timeout or log options
bandwidth Set bandwidth informational parameter
cdp CDP interface subcommands
crypto Encryption/Decryption commands
delay Specify interface throughput delay
description Interface specific description
encryption Configure dot11 encryption parameters
exit Exit from interface configuration mode
fair-queue Enable Fair Queuing on an Interface
hold-queue Set hold queue depth
ip Interface Internet Protocol config commands
mac-address Manually set interface MAC address
mtu Set the interface Maximum Transmission Unit (MTU)
no Negate a command or set its defaults
priority-group Assign a priority group to an interface
service-policy Configure QoS Service Policy
shutdown Shutdown the selected interface
speed Set allowed radio bit rates
ssid Configure radio service set parameters
tx-ring-limit Configure PA level transmit ring limit
i'll consider the problem *mostly* solved. I was able to assign the SSD.
The infrastructure command may be expendable in this case... to be determined
here is our configuration for R3
R3#
show run
Building configuration...
Current configuration : 1682 bytes
!
version 15.1
no service timestamps log datetime msec
no service timestamps debug datetime msec
no service password-encryption
!
hostname R3
!
!
!
enable secret 5 $1$mERr$V5ujdIM9bTB/I.ipB0gkJ0
!
!
ip dhcp excluded-address 172.16.10.1 172.16.10.10
!
ip dhcp pool Admin
network 172.16.10.0 255.255.255.0
default-router 172.16.10.1
!
dot11 ssid ADMIN
authentication open
guest-mode
!
dot11 ssid ADMIN2
authentication open
guest-mode
!
!
!
ip cef
no ipv6 cef
!
!
!
!
license udi pid CISCO2811/K9 sn FTX1017RE40-
!
!
!
!
!
!
!
!
!
no ip domain-lookup
ip name-server 172.16.10.4
!
!
spanning-tree mode pvst
!
!
!
!
!
!
interface FastEthernet0/0
description connection to corp router
ip address 10.1.5.2 255.255.255.0
duplex auto
speed auto
!
interface FastEthernet0/1
no ip address
duplex auto
speed auto
shutdown
!
interface Dot11Radio0/0/0
description WAN for mobile
ip address 172.16.10.1 255.255.255.0
speed 12.0 18.0 24.0 36.0 48.0 54.0 6.0 9.0 basic-1.0 basic-11.0 basic-2.0 basic-5.5
ssid ADMIN2
!
interface Dot11Radio0/0/1
no ip address
speed 18.0 36.0 48.0 54.0 9.0 basic-12.0 basic-24.0 basic-6.0
!
interface Serial0/1/0
no ip address
clock rate 2000000
!
interface Serial0/1/1
no ip address
clock rate 2000000
!
interface Vlan1
no ip address
shutdown
!
router rip
version 2
network 10.0.0.0
network 172.16.0.0
!
ip classless
ip route 0.0.0.0 0.0.0.0 10.1.5.1
!
ip flow-export version 9
!
!
!
banner motd ^C this is R3 $
this is R3 ^C
!
!
!
!
!
line con 0
exec-timeout 0 0
password console
logging synchronous
login
!
line aux 0
password aux
login
!
line vty 0 4
password telnet
login
line vty 5 15
password telnet
login
!
!
!
end
to summarize...
the book is a little off here.
-----------------------------------------------------------------------------------------------
R3(config-if)#
int dot11radio0/0/0
R3(config-if)#
ip address 172.16.10.1 255.255.255.0
R3(config-if)#
description WLAN for mobile user
R3(config-if)#
no shut
at this point we have created a wireless interface with an IP address but no SSID exists on this router
interface Dot11Radio0/0/0
description test router 2
ip address 172.16.10.1 255.255.255.0
speed 12.0 18.0 24.0 36.0 48.0 54.0 6.0 9.0 basic-1.0 basic-11.0 basic-2.0 basic-5.5
Trying to use the command "ssid ADMIN" doesnt work here. The below commands are invalid here:
R3(config-if)#
ssid ADMIN
R3(config-if-ssid)#
guest-mode
R3(config-if-ssid)#
authentication open
R3(config-if-ssid)#
ingrastructure-ssid
R3(config-if-ssid)#
exit
-----------------------------------------------------------------------------------------------
We need to drop out of config-if, back to config, and enter SSID config mode
-----------------------------------------------------------------------------------------------
R3(config-if)#
exit
R3(config)#
dot11 ssid ADMIN2 creates an ssid named ADMIN2, and puts us into SSID config mode
R3(config-ssid)#
guest-mode
R3(config-ssid)#
authentication open
then out of config-ssid and back to interface config
R3(config-ssid)#
exit
R3(config)
int dot11r0/0/0
R3(config-if)
?
arp Set arp type (arpa, probe, snap) or timeout or log options
bandwidth Set bandwidth informational parameter
cdp CDP interface subcommands
crypto Encryption/Decryption commands
delay Specify interface throughput delay
description Interface specific description
encryption Configure dot11 encryption parameters
exit Exit from interface configuration mode
fair-queue Enable Fair Queuing on an Interface
hold-queue Set hold queue depth
ip Interface Internet Protocol config commands
mac-address Manually set interface MAC address
mtu Set the interface Maximum Transmission Unit (MTU)
no Negate a command or set its defaults
priority-group Assign a priority group to an interface
service-policy Configure QoS Service Policy
shutdown Shutdown the selected interface
speed Set allowed radio bit rates
ssid Configure radio service set parameters
tx-ring-limit Configure PA level transmit ring limit
we have the option for ssid
R3(config-if)
ssid ADMIN2
%LINK-5-CHANGED: Interface Dot11Radio0/0/0, changed state to administratively down
%LINEPROTO-5-UPDOWN: Line protocol on Interface Dot11Radio0/0/0, changed state to down
%LINK-5-CHANGED: Interface Dot11Radio0/0/0, changed state to up
%LINEPROTO-5-UPDOWN: Line protocol on Interface Dot11Radio0/0/0, changed state to up
the router resets the interface..
-----------------------------------------------------------------------------------------------
R3(config-if)
do show run
[cut]
!
!
dot11 ssid ADMIN2
authentication open
guest-mode
!
!
[cut]
!
interface Dot11Radio0/0/0
description test router 2
ip address 172.16.10.1 255.255.255.0
speed 12.0 18.0 24.0 36.0 48.0 54.0 6.0 9.0 basic-1.0 basic-11.0 basic-2.0 basic-5.5
ssid ADMIN2
!
[cut]
the SSID is created and assigned to the interface
To summarize.
Wrong: create the dot11 interface, then create the SSID from CONFIG-IF mode, which puts you into CONFIG-IF-SSID (there is no such mode on this router) mode, then modify the ssid from there...
Correct: create the dot11 interface. Exit CONFIG-IF and go back to GLOBAL CONFIG. Create the SSID which puts you in CONFIG-SSID mode.
Configure the ssid. Then exit CONFIG-SSID. Back into CONFIG-IF, assign the SSID
We have one more task for R3- Configuring the DHCP pool for wireless clients.
R3(config)#
ip dhcp pool Admin creating the pool name as "Admin"
R3(dhcp-config)#
network 172.16.10.0 255.255.255.0
R3(dhcp-config)#
default-router 172.16.10.1 aka default-gateway for clients in the pool
R3(dhcp-config)#
ip name-server 172.16.10.4 dns server
*automatically exits dhcp-config prompt*
R3(config)#
ip dhcp excluded-address 172.16.10.1 172.16.10.10 excludes the range given
172.16.10.1 is the router interface- we need to specifically exclude it from the pool
this setup should allow the wireless client to pick up an IP after connecting to the open SSID.
However, I was having trouble at first-
even though I seemed to have the SSID set correctly, i was hitting a WEP password prompt
i didnt see any obvious issues with the wifi module im using on the laptop:
The Linksys-WPC300N module provides one 2.4GHz wireless interface suitable for connection to wireless networks.
The module supports protocols that use Ethernet for LAN access.
I ended up creating a new SSID, with the same settings as the original:
R3(config)#
dot11 ssid ADMIN2
R3(config-ssid)#
guest-mode
R3(config-ssid)#
authentication open
and then I assigned the ip address to ssid ADMIN2 instead of the orginal ADMIN ssid
R3(config)#
int dot110/0/0
R3(config-if)#
ip address 172.16.10.1 255.255.255.0
R3(config-if)#
description WLAN for mobile user
R3(config-if)#
no shut
R3(config-if)#
ssid ADMIN2
R3#
show run
Building configuration...
Current configuration : 1467 bytes
!
version 15.1
no service timestamps log datetime msec
no service timestamps debug datetime msec
no service password-encryption
!
hostname R3
!
!
!
enable secret 5 $1$mERr$V5ujdIM9bTB/I.ipB0gkJ0
!
!
ip dhcp excluded-address 172.16.10.1 172.16.10.10
!
ip dhcp pool Admin
network 172.16.10.0 255.255.255.0
default-router 172.16.10.1
!
dot11 ssid ADMIN
authentication open
guest-mode
!
dot11 ssid ADMIN2
authentication open
guest-mode
!
!
!
ip cef
no ipv6 cef
!
!
!
!
license udi pid CISCO2811/K9 sn FTX1017RE40-
!
!
!
!
!
!
!
!
!
no ip domain-lookup
ip name-server 172.16.10.4
!
!
spanning-tree mode pvst
!
!
!
!
!
!
interface FastEthernet0/0
description connection to corp router
ip address 10.1.5.2 255.255.255.0
duplex auto
speed auto
!
interface FastEthernet0/1
no ip address
duplex auto
speed auto
shutdown
!
interface Dot11Radio0/0/0
description WAN for mobile
ip address 172.16.10.1 255.255.255.0
speed 12.0 18.0 24.0 36.0 48.0 54.0 6.0 9.0 basic-1.0 basic-11.0 basic-2.0 basic-5.5
ssid ADMIN2
!
interface Dot11Radio0/0/1
no ip address
speed 18.0 36.0 48.0 54.0 9.0 basic-12.0 basic-24.0 basic-6.0
!
interface Vlan1
no ip address
shutdown
!
ip classless
!
ip flow-export version 9
!
!
!
banner motd ^C this is R3 $
this is R3 ^C
!
!
!
!
!
line con 0
exec-timeout 0 0
password console
logging synchronous
login
!
line aux 0
password aux
login
!
line vty 0 4
password telnet
login
line vty 5 15
password telnet
login
!
!
!
end
Recall the DHCP configuration on R3:
R3(config)#
ip dhcp pool Admin creating the pool name as "Admin"
R3(dhcp-config)#
network 172.16.10.0 255.255.255.0
R3(dhcp-config)#
default-router 172.16.10.1 aka default-gateway for clients in the pool
R3(dhcp-config)#
ip name-server 172.16.10.4 dns server
*automatically exits dhcp-config prompt*
R3(config)#
ip dhcp excluded-address 172.16.10.1 172.16.10.10 excludes the range given
172.16.10.1 is the router interface- we need to specifically exclude it from the pool
we can check the configuration:
R3#
show ip dhcp pool
Pool Admin :
Utilization mark (high/low) : 100 / 0
Subnet size (first/next) : 0 / 0
Total addresses : 254
Leased addresses : 1
Excluded addresses : 1
Pending event : none
1 subnet is currently in the pool
Current index IP address range Leased/Excluded/Total
172.16.10.1 172.16.10.1 - 172.16.10.254 1 / 1 / 254
R3#
show ip dhcp binding
IP address Client-ID/ Lease expiration Type
Hardware address
172.16.10.11 00D0.979A.733B -- Automatic
the show command is becoming more familiar
R3#
show ip?
access-lists List access lists
arp IP ARP table
bgp BGP information
cache IP fast-switching route cache
cef Cisco Express Forwarding
dhcp Show items in the DHCP database
eigrp IP-EIGRP show commands
inspect CBAC (Context Based Access Control) information
interface IP interface status and configuration
ips IPS (Intrusion Prevention System) information
nat IP NAT information
nbar Network-Based Application Recognition
ospf OSPF information
protocols IP routing protocol process parameters and statistics
rip IP RIP show commands
route IP routing table
ssh Information on SSH
we'll use show ip route soon on all the routers. For now, here is the output for R3:
R3#
show ip route
Codes: L - local, C - connected, S - static, R - RIP, M - mobile, B - BGP
D - EIGRP, EX - EIGRP external, O - OSPF, IA - OSPF inter area
N1 - OSPF NSSA external type 1, N2 - OSPF NSSA external type 2
E1 - OSPF external type 1, E2 - OSPF external type 2, E - EGP
i - IS-IS, L1 - IS-IS level-1, L2 - IS-IS level-2, ia - IS-IS inter area
* - candidate default, U - per-user static route, o - ODR
P - periodic downloaded static route
Gateway of last resort is not set
10.0.0.0/8 is variably subnetted, 2 subnets, 2 masks
C 10.1.5.0/24 is directly connected, FastEthernet0/0
L 10.1.5.2/32 is directly connected, FastEthernet0/0
172.16.0.0/16 is variably subnetted, 2 subnets, 2 masks
C 172.16.10.0/24 is directly connected, Dot11Radio0/0/0
L 172.16.10.1/32 is directly connected, Dot11Radio0/0/0
Before moving on to the routing configurations, here is a review of the topology
I have switched over to the DrawIO diagram app to lay out the topology.
The Packet Tracer diagram becomes
too crowded to see the labels; it's labeling system forces awkward positioning of the objects; the interface
label's cant be moved, so if objects are too close together their labels cover eachother.. not good.
DrawIO allows a cleaner layout with plenty of room to label interfaces and ip addresses.
As a compromise, I'll use both.
I have the packet tracer objects spread out just enough to see the interfaces
and the label for each router. From here I can jump into the CLI for each device.
The DrawIO diagram allows me to cleary see IP addresses
I want to also review all of the configurations we just performed:
PROBLEM
The book specifies that of the two serial conections between R1 and Corp, there should be a DCE on each end..
Both of my DCE's are on the same end.
First lets be sure we understand what DCE means:
networkengineering.stackexchange.com/
One side of the link (DCE), has to transmit the clock signal, which controls the data rate, and the other side (DTE) receives the clock signal.
That is good enough for now. Note that while the book does specify in the diagram that each side should have a DCE, it was not actually mentioned in the configs.
We did not set a DCE or clock rate when conifguring those interfaces.
To fix this in my Packet Tracer topology, I did some quick research:
While this post wasnt pertaining to Packet Tracer, it got me thinking about the cable itself.
I deleted both of my existing serial connections and looked at the options for creating a new cable.
I noticed one is a DCE and one is a DTE:
Fixed the issue
back to the configuration overview: 4 routers, abbreviated show run output
Corp
interface FastEthernet0/0
description connection to R3
ip address 10.1.5.1 255.255.255.0
duplex auto
speed auto
!
interface FastEthernet0/1
no ip address
duplex auto
speed auto
shutdown
!
interface Serial0/0/0
description 1st connection to R1
ip address 10.1.2.1 255.255.255.0
!
interface Serial0/0/1
description 2nd connection to R1
ip address 10.1.3.1 255.255.255.0
clock rate 2000000
!
interface Serial0/1/0
description connection to R2
ip address 10.1.4.1 255.255.255.0
!
interface Vlan1
description Switch Card to Core Network
ip address 10.1.1.1 255.255.255.0
!
interface FastEthernet1/0
description switch port connection to WWW Server
switchport mode access
switchport nonegotiate
!
interface FastEthernet1/1
description switch port connection to Email Server
switchport mode access
switchport nonegotiate
!
interface FastEthernet1/2
description switch port connection to DNS Server
switchport mode access
switchport nonegotiate
!
R1
interface FastEthernet0/0
description connection to Finance
ip address 192.168.10.1 255.255.255.0
duplex auto
speed auto
!
interface FastEthernet0/1
description connection to Marketing
ip address 192.168.20.1 255.255.255.0
duplex auto
speed auto
!
interface Serial0/0/0
description 1st connection to Corp router
ip address 10.1.2.2 255.255.255.0
clock rate 2000000
!
interface Serial0/0/1
description 2nd connecction to Corp router
ip address 10.1.3.2 255.255.255.0
!
R2
interface FastEthernet0/0
description Connection to Sales PC
ip address 192.168.30.1 255.255.255.0
duplex auto
speed auto
!
interface FastEthernet0/1
description Connection to HR PC
ip address 192.168.40.1 255.255.255.0
duplex auto
speed auto
!
interface Serial0/0/0
description Connection to Corp Router
ip address 10.1.4.2 255.255.255.0
clock rate 2000000
!
interface Serial0/0/1
no ip address
clock rate 2000000
shutdown
!
R3
interface FastEthernet0/0
description connection to corp router
ip address 10.1.5.2 255.255.255.0
duplex auto
speed auto
!
interface FastEthernet0/1
no ip address
duplex auto
speed auto
shutdown
!
interface Dot11Radio0/0/0
description WAN for mobile
ip address 172.16.10.1 255.255.255.0
speed 12.0 18.0 24.0 36.0 48.0 54.0 6.0 9.0 basic-1.0 basic-11.0 basic-2.0 basic-5.5
ssid ADMIN2
and here is the output of show ip route for each router
Codes: C - connected, S - static, I - IGRP, R - RIP, M - mobile, B - BGP
D - EIGRP, EX - EIGRP external, O - OSPF, IA - OSPF inter area
N1 - OSPF NSSA external type 1, N2 - OSPF NSSA external type 2
E1 - OSPF external type 1, E2 - OSPF external type 2, E - EGP
i - IS-IS, L1 - IS-IS level-1, L2 - IS-IS level-2, ia - IS-IS inter area
* - candidate default, U - per-user static route, o - ODR
P - periodic downloaded static route
Gateway of last resort is not set
Corp
10.0.0.0/24 is subnetted, 2 subnets
C 10.1.2.0 is directly connected, Serial0/0/0
C 10.1.3.0 is directly connected, Serial0/0/1
C 192.168.10.0/24 is directly connected, FastEthernet0/0
C 192.168.20.0/24 is directly connected, FastEthernet0/1
R1
10.0.0.0/24 is subnetted, 2 subnets
C 10.1.2.0 is directly connected, Serial0/0/0
C 10.1.3.0 is directly connected, Serial0/0/1
C 192.168.10.0/24 is directly connected, FastEthernet0/0
C 192.168.20.0/24 is directly connected, FastEthernet0/1
R2
10.0.0.0/24 is subnetted, 1 subnets
C 10.1.4.0 is directly connected, Serial0/0/0
C 192.168.30.0/24 is directly connected, FastEthernet0/0
C 192.168.40.0/24 is directly connected, FastEthernet0/1
R3
10.0.0.0/8 is variably subnetted, 2 subnets, 2 masks
C 10.1.5.0/24 is directly connected, FastEthernet0/0
L 10.1.5.2/32 is directly connected, FastEthernet0/0
172.16.0.0/16 is variably subnetted, 2 subnets, 2 masks
C 172.16.10.0/24 is directly connected, Dot11Radio0/0/0
L 172.16.10.1/32 is directly connected, Dot11Radio0/0/0
Note that this is before we have configured any 'routing'. We are seeing configured, directly connected networks.
The output for R3 is particularly interesting
What does 'variably' subnetted mean, and what is the "L" next to these routes. And why do they have a mask of 32?
R3
10.0.0.0/8 is variably subnetted, 2 subnets, 2 masks
C 10.1.5.0/24 is directly connected, FastEthernet0/0
L 10.1.5.2/32 is directly connected, FastEthernet0/0
172.16.0.0/16 is variably subnetted, 2 subnets, 2 masks
C 172.16.10.0/24 is directly connected, Dot11Radio0/0/0
L 172.16.10.1/32 is directly connected, Dot11Radio0/0/0
Cisco forums
That makes sense, but my question is why did the other routing tables not behave the same way? R3 is the only one that shows "L" routes.
The book tells us we're using two different model routers, and indeed they are running different IOS versions:
NOTE that at the time the book was published IOS 15 was not released yet, so the book assumes all routers are running 12.4
But that still doesnt explain why Corp and R3 are behaving differently..
Corp
10.0.0.0/24 is subnetted, 2 subnets
C 10.1.2.0 is directly connected, Serial0/0/0
C 10.1.3.0 is directly connected, Serial0/0/1
C 192.168.10.0/24 is directly connected, FastEthernet0/0
C 192.168.20.0/24 is directly connected, FastEthernet0/1
R1
10.0.0.0/24 is subnetted, 2 subnets
C 10.1.2.0 is directly connected, Serial0/0/0
C 10.1.3.0 is directly connected, Serial0/0/1
C 192.168.10.0/24 is directly connected, FastEthernet0/0
C 192.168.20.0/24 is directly connected, FastEthernet0/1
R2
10.0.0.0/24 is subnetted, 1 subnets
C 10.1.4.0 is directly connected, Serial0/0/0
C 192.168.30.0/24 is directly connected, FastEthernet0/0
C 192.168.40.0/24 is directly connected, FastEthernet0/1
R3
10.0.0.0/8 is variably subnetted, 2 subnets, 2 masks
C 10.1.5.0/24 is directly connected, FastEthernet0/0
L 10.1.5.2/32 is directly connected, FastEthernet0/0
172.16.0.0/16 is variably subnetted, 2 subnets, 2 masks
C 172.16.10.0/24 is directly connected, Dot11Radio0/0/0
L 172.16.10.1/32 is directly connected, Dot11Radio0/0/0
how are Corp and R3 different?
The answer is, they are not...
I have accidentally displayed the R1 output to the Corp windows. Error in translating data from the IOS to this webpage..
here's the corrected output.
Corp
10.0.0.0/8 is variably subnetted, 10 subnets, 2 masks
C 10.1.1.0/24 is directly connected, Vlan1
L 10.1.1.1/32 is directly connected, Vlan1
C 10.1.2.0/24 is directly connected, Serial0/0/0
L 10.1.2.1/32 is directly connected, Serial0/0/0
C 10.1.3.0/24 is directly connected, Serial0/0/1
L 10.1.3.1/32 is directly connected, Serial0/0/1
C 10.1.4.0/24 is directly connected, Serial0/1/0
L 10.1.4.1/32 is directly connected, Serial0/1/0
C 10.1.5.0/24 is directly connected, FastEthernet0/0
L 10.1.5.1/32 is directly connected, FastEthernet0/0
R1
10.0.0.0/24 is subnetted, 2 subnets
C 10.1.2.0 is directly connected, Serial0/0/0
C 10.1.3.0 is directly connected, Serial0/0/1
C 192.168.10.0/24 is directly connected, FastEthernet0/0
C 192.168.20.0/24 is directly connected, FastEthernet0/1
R2
10.0.0.0/24 is subnetted, 1 subnets
C 10.1.4.0 is directly connected, Serial0/0/0
C 192.168.30.0/24 is directly connected, FastEthernet0/0
C 192.168.40.0/24 is directly connected, FastEthernet0/1
R3
10.0.0.0/8 is variably subnetted, 2 subnets, 2 masks
C 10.1.5.0/24 is directly connected, FastEthernet0/0
L 10.1.5.2/32 is directly connected, FastEthernet0/0
172.16.0.0/16 is variably subnetted, 2 subnets, 2 masks
C 172.16.10.0/24 is directly connected, Dot11Radio0/0/0
L 172.16.10.1/32 is directly connected, Dot11Radio0/0/0
We do indeed see consistent behavior differences between IOS versions 12.4 and 15.1
recap Corp and R3 outputs:
update topology with Router versions
That covers the first half of Chapter 8. Now we are ready to configure IP routing on our network.
There are three ways: Static, Default, Dynamic
To set up static routes, we simply need to program the routes using the ip route command
Syntax
ip route
[
destination network
]
[
mask
]
[
next hop
]
[
exitinterface
]
[
administrative distance
]
[
permanent
]
destination network and mask
the network data we're adding to the routing table
next-hop address
the address of the next-hop router that will receive the packet and forward to the remote network.
This is the IP address of a router interface that is directly connected.
It must be pingable.
exit interface
can be used instead of next hop address
administrative distance
by default, static routes have an admin distance of 1 if you use a next hop, or 0 if you use exit interface.
You can change the value by adding an administrative weight at the end of the command. More on this later with dynamic routing.
permanent
if the interface is shut down or the router cant communicate to the next hp router, the route will automatically be discarded from the table by default.
The 'permanent' option keeps the entry in the routing table indefenitely.
-----------------------------------------------------------------------------------------------------
Corp has automatically picked up 5 routes that are directly connected:
10.1.1.0 to corp switch card
10.1.2.0 to R1
10.1.3.0 to R1
10.1.4.0 to R2
10.1.5.0 to R3
We need to program 5 more routes:
192.168.10.0 traverse R1
192.168.20.0 traverse R1
192.168.30.0 traverse R1
192.168.40.0 traverse R2
172.16.10.0 traverse R3
-----------------------------------------------------------------------------------------------------
R1 has automatically picked up 4 routes that are directly connected:
10.1.2.0
10.1.3.0
192.168.10.0
192.168.20.0
We need to program 6 more routes:
10.1.1.0
10.1.4.0
10.1.5.0
192.168.30.0
192.168.40.0
172.16.10.0
-----------------------------------------------------------------------------------------------------
R2 has automatically picked up 3 routes that are directly connected:
10.1.4.0
192.168.30.0
192.168.40.0
We need to program 7 more routes:
10.1.1.0
10.1.2.0
10.1.3.0
10.1.5.0
192.168.10.0
192.168.20.0
172.16.10.0
-----------------------------------------------------------------------------------------------------
R3 has automatically picked up 2 routes that are directly connected:
10.1.5.0
172.16.10.0
We need to program 8 more routes:
10.1.1.0
10.1.2.0
10.1.3.0
10.1.4.0
192.168.10.0
192.168.20.0
192.168.30.0
192.168.40.0
Notice the pattern- each router ends up with 10 routes
There are 10 routes total in this topology. AKA ten broadcast domains
Programming the routes
Corp
Corp(config)#
ip route 192.168.10.0 255.255.255.0 10.1.2.2 150
Corp(config)#
ip route 192.168.20.0 255.255.255.0 10.1.3.2 150
Corp(config)#
ip route 192.168.30.0 255.255.255.0 10.1.4.2 150
Corp(config)#
ip route 192.168.40.0 255.255.255.0 10.1.4.2 150
Corp(config)#
ip route 172.16.10.0 255.255.255.0 10.1.5.2 150
Corp(config)#
do show ip route
In the first line, the router is saying that a
classful A network is being subnetted
There are 5 routes directly connected
We see two lines per route (one for the network and one
for the interface(/32)-
10.0.0.0/8 is variably subnetted, 10 subnets, 2 masks
C 10.1.1.0/24 is directly connected, Vlan1
L 10.1.1.1/32 is directly connected, Vlan1
C 10.1.2.0/24 is directly connected, Serial0/0/0
L 10.1.2.1/32 is directly connected, Serial0/0/0
C 10.1.3.0/24 is directly connected, Serial0/0/1
L 10.1.3.1/32 is directly connected, Serial0/0/1
C 10.1.4.0/24 is directly connected, Serial0/1/0
L 10.1.4.1/32 is directly connected, Serial0/1/0
C 10.1.5.0/24 is directly connected, FastEthernet0/0
L 10.1.5.1/32 is directly connected, FastEthernet0/0
and 5 routes that require traversal of a router to reach
172.16.0.0/24 is subnetted, 1 subnets
S 172.16.10.0/24 [150/0] via 10.1.5.2
S 192.168.10.0/24 [150/0] via 10.1.2.2
S 192.168.20.0/24 [150/0] via 10.1.3.2
S 192.168.30.0/24 [150/0] via 10.1.4.2
S 192.168.40.0/24 [150/0] via 10.1.4.2
R1
R1(config)#
ip route 10.1.1.0 255.255.255.0 10.1.2.1 150
R1(config)#
ip route 10.1.4.0 255.255.255.0 10.1.3.1 150
R1(config)#
ip route 10.1.5.0 255.255.255.0 10.1.2.1 150
R1(config)#
ip route 192.168.30.0 255.255.255.0 10.1.3.1 150
R1(config)#
ip route 192.168.40.0 255.255.255.0 10.1.2.1 150
R1(config)#
ip route 172.16.10.0 255.255.255.0 10.1.3.1 150
the only way to get across the corp router is to go into it via 10.1.2.1 or 10.1.3.1
R1(config)#
do show ip route
10.0.0.0/24 is subnetted, 5 subnets
S 10.1.1.0 [150/0] via 10.1.2.1
C 10.1.2.0 is directly connected, Serial0/0/0
C 10.1.3.0 is directly connected, Serial0/0/1
S 10.1.4.0 [150/0] via 10.1.3.1
S 10.1.5.0 [150/0] via 10.1.2.1
172.16.0.0/24 is subnetted, 1 subnets
S 172.16.10.0 [150/0] via 10.1.3.1
C 192.168.10.0/24 is directly connected, FastEthernet0/0
C 192.168.20.0/24 is directly connected, FastEthernet0/1
S 192.168.30.0/24 [150/0] via 10.1.3.1
S 192.168.40.0/24 [150/0] via 10.1.2.1
R2
R2(config)#
iproute 10.1.1.0 255.255.255.0 10.1.4.1 150
R2(config)#
iproute 10.1.2.0 255.255.255.0 10.1.4.1 150
R2(config)#
iproute 10.1.3.0 255.255.255.0 10.1.4.1 150
R2(config)#
iproute 10.1.5.0 255.255.255.0 10.1.4.1 150
R2(config)#
iproute 192.168.10.0 255.255.255.0 10.1.4.1 150
R2(config)#
iproute 192.168.20.0 255.255.255.0 10.1.4.1 150
the only way to get across Corp is to go into it via 10.1.4.1
R2(config)#
do show ip route
10.0.0.0/24 is subnetted, 5 subnets
S 10.1.1.0 [150/0] via 10.1.4.1
S 10.1.2.0 [150/0] via 10.1.4.1
S 10.1.3.0 [150/0] via 10.1.4.1
C 10.1.4.0 is directly connected, Serial0/0/0
S 10.1.5.0 [150/0] via 10.1.4.1
172.16.0.0/24 is subnetted, 1 subnets
S 172.16.10.0 [150/0] via 10.1.4.1
S 192.168.10.0/24 [150/0] via 10.1.4.1
S 192.168.20.0/24 [150/0] via 10.1.4.1
C 192.168.30.0/24 is directly connected, FastEthernet0/0
C 192.168.40.0/24 is directly connected, FastEthernet0/1
R3
R3(config)#
ip route 10.1.1.0 255.255.255.0 fastethernet 0/0 150
R3(config)#
ip route 10.1.2.0 255.255.255.0 fastethernet 0/0 150
R3(config)#
ip route 10.1.3.0 255.255.255.0 fastethernet 0/0 150
R3(config)#
ip route 10.1.4.0 255.255.255.0 fastethernet 0/0 150
R3(config)#
ip route 192.168.10.0 255.255.255.0 fastethernet 0/0 150
R3(config)#
ip route 192.168.20.0 255.255.255.0 fastethernet 0/0 150
R3(config)#
ip route 192.168.30.0 255.255.255.0 fastethernet 0/0 150
R3(config)#
ip route 192.168.40.0 255.255.255.0 fastethernet 0/0 150
the only way to get across Corp is to EXIT R3 via F0/0
R3(config)#
do show ip route
10.0.0.0/8 is variably subnetted, 6 subnets, 2 masks
S 10.1.1.0/24 is directly connected, FastEthernet0/0
S 10.1.2.0/24 is directly connected, FastEthernet0/0
S 10.1.3.0/24 is directly connected, FastEthernet0/0
S 10.1.4.0/24 is directly connected, FastEthernet0/0
C 10.1.5.0/24 is directly connected, FastEthernet0/0
L 10.1.5.2/32 is directly connected, FastEthernet0/0
172.16.0.0/16 is variably subnetted, 2 subnets, 2 masks
C 172.16.10.0/24 is directly connected, Dot11Radio0/0/0
L 172.16.10.1/32 is directly connected, Dot11Radio0/0/0
S 192.168.10.0/24 is directly connected, FastEthernet0/0
S 192.168.20.0/24 is directly connected, FastEthernet0/0
S 192.168.30.0/24 is directly connected, FastEthernet0/0
S 192.168.40.0/24 is directly connected, FastEthernet0/0
before verifying connectivity across the network, we need to make sure all of our hosts are set. The book is giving us the IP addresses for the servers:
Server Gateway 10.1.1.1
ServerWeb 10.1.1.2
ServerEmail 10.1.1.3
ServerDNS 10.1.1.4
Now we can do some testing across the network:
R3#
ping 10.1.2.2
traverse Corp to R1
R3#
ping 10.1.1.1
traverse Corp to a Corp interface we arent directly connected to
R3#
ping 10.1.1.2
traverse Corp to Web server
R3#
ping 10.1.1.3
traverse Corp to Email server
R3#
ping 10.1.1.4
traverse Corp to DNS server
MobileUser
ping 192.168.10.2
traverse R3, Corp, R1 to Finance client
MobileUser
tracert 192.168.10.2
traverse R3, Corp, R1 to Finance client
Tracing route to 192.168.10.2 over a maximum of 30 hops:
1 19 ms 5 ms 20 ms 172.16.10.1
2 20 ms 6 ms 11 ms 10.1.5.1
3 11 ms 15 ms 10 ms 10.1.3.2
4 9 ms 13 ms 22 ms 192.168.10.2
Trace complete.
notice how the trace doesnt count an egress as a hop, only an ingress
ALSO NOTE that tracert is a Windows command.
the IOS equivalent is traceroute
notice how the output differs from the Windows command
R3
traceroute 192.168.10.2
Type escape sequence to abort.
Tracing the route to 192.168.10.2
1 10.1.5.1 0 msec 0 msec 0 msec
2 10.1.2.2 6 msec 0 msec 5 msec
3 192.168.10.2 1 msec 4 msec 3 msec
Default Routing
we could have done this on R3
R3(config)#
ip route 0.0.0.0 0.0.0.0 10.1.5.1
as an alternative to this configuration on R3
R3(config)#
ip route 10.1.1.0 255.255.255.0 fastethernet 0/0 150
R3(config)#
ip route 10.1.2.0 255.255.255.0 fastethernet 0/0 150
R3(config)#
ip route 10.1.3.0 255.255.255.0 fastethernet 0/0 150
R3(config)#
ip route 10.1.4.0 255.255.255.0 fastethernet 0/0 150
R3(config)#
ip route 192.168.10.0 255.255.255.0 fastethernet 0/0 150
R3(config)#
ip route 192.168.20.0 255.255.255.0 fastethernet 0/0 150
R3(config)#
ip route 192.168.30.0 255.255.255.0 fastethernet 0/0 150
R3(config)#
ip route 192.168.40.0 255.255.255.0 fastethernet 0/0 150
the only way to get across Corp is to EXIT R3 via F0/0
This is called default routing. It should only be used on 'stub routers'- those with only one exit path out of the network.
if you try to put a default route on a non-stub router, you could create loops, since there will be more than one path to other routers...
Think of a default route as a static route that uses a wildcard address and mask. The wildcard is 0.0.0.0
to further analyze this comparison, I'm going to remove the routes from R3...
R3(config)#
no ip route 10.1.1.0 255.255.255.0 fastethernet0/0 150
R3(config)#
no ip route 10.1.2.0 255.255.255.0 fastethernet0/0 150
R3(config)#
no ip route 10.1.3.0 255.255.255.0 fastethernet0/0 150
R3(config)#
no ip route 10.1.4.0 255.255.255.0 fastethernet0/0 150
R3(config)#
no ip route 192.168.10.0 255.255.255.0 fastethernet0/0 150
R3(config)#
no ip route 192.168.20.0 255.255.255.0 fastethernet0/0 150
R3(config)#
no ip route 192.168.30.0 255.255.255.0 fastethernet0/0 150
R3(config)#
no ip route 192.168.40.0 255.255.255.0 fastethernet0/0 150
and then set the default route instead.
R3#
ip route 0.0.0.0 0.0.0.0 10.1.5.1 --- ingress at next hop
OR
R3#
ip route 0.0.0.0 0.0.0.0 Fa0/0 --- egress interface
Then compare the output of show ip route
static routes set
R3#
show ip route
Gateway of last resort is not set
10.0.0.0/8 is variably subnetted, 6 subnets, 2 masks
S 10.1.1.0/24 is directly connected, FastEthernet0/0
S 10.1.2.0/24 is directly connected, FastEthernet0/0
S 10.1.3.0/24 is directly connected, FastEthernet0/0
S 10.1.4.0/24 is directly connected, FastEthernet0/0
C 10.1.5.0/24 is directly connected, FastEthernet0/0
L 10.1.5.2/32 is directly connected, FastEthernet0/0
172.16.0.0/16 is variably subnetted, 2 subnets, 2 masks
C 172.16.10.0/24 is directly connected, Dot11Radio0/0/0
L 172.16.10.1/32 is directly connected, Dot11Radio0/0/0
S 192.168.10.0/24 is directly connected, FastEthernet0/0
S 192.168.20.0/24 is directly connected, FastEthernet0/0
S 192.168.30.0/24 is directly connected, FastEthernet0/0
S 192.168.40.0/24 is directly connected, FastEthernet0/0
default route set
R3#
show ip route
Gateway of last resort is 10.1.5.1 to network 0.0.0.0
10.0.0.0/8 is variably subnetted, 2 subnets, 2 masks
C 10.1.5.0/24 is directly connected, FastEthernet0/0
L 10.1.5.2/32 is directly connected, FastEthernet0/0
172.16.0.0/16 is variably subnetted, 2 subnets, 2 masks
C 172.16.10.0/24 is directly connected, Dot11Radio0/0/0
L 172.16.10.1/32 is directly connected, Dot11Radio0/0/0
S* 0.0.0.0/0 [1/0] via 10.1.5.1
two directly connected networks- 10.1.5.0 and 172.16.10.0
anything not included in those networks goes to ingress of attached neighbor Corp 10.1.5.1
in this toplogy, that includes:
192.168.10.0
192.168.20.0
192.168.30.0
192.168.40.0
and
10.1.1.0
10.1.2.0
10.1.3.0
10.1.4.0
RIP Routing Information Protocol
R1(config)#
router ?
bgp Border Gateway Protocol (BGP)
eigrp Enhanced Interior Gateway Routing Protocol (EIGRP)
ospf Open Shortest Path First (OSPF)
rip Routing Information Protocol (RIP)
set RIP on Corp
Corp(config)#
router rip
Corp(config-router)#
network 10.0.0.0
set RIP on R1
R1(config)#
router rip
R1(config-router)#
network 10.0.0.0
R1 routing table
R1(config)#
do show ip route
10.0.0.0/24 is subnetted, 5 subnets
R 10.1.1.0 [120/1] via 10.1.2.1, 00:00:21, Serial0/0/0
[120/1] via 10.1.3.1, 00:00:21, Serial0/0/1
C 10.1.2.0 is directly connected, Serial0/0/0
C 10.1.3.0 is directly connected, Serial0/0/1
R 10.1.4.0 [120/1] via 10.1.2.1, 00:00:21, Serial0/0/0
[120/1] via 10.1.3.1, 00:00:21, Serial0/0/1
R 10.1.5.0 [120/1] via 10.1.2.1, 00:00:21, Serial0/0/0
[120/1] via 10.1.3.1, 00:00:21, Serial0/0/1
172.16.0.0/24 is subnetted, 1 subnets
S 172.16.10.0 [150/0] via 10.1.3.1
C 192.168.10.0/24 is directly connected, FastEthernet0/0
C 192.168.20.0/24 is directly connected, FastEthernet0/1
S 192.168.30.0/24 [150/0] via 10.1.3.1
S 192.168.40.0/24 [150/0] via 10.1.2.1
here's R1 before RIP, with only static routes set:
R1(config)#
do show ip route
10.0.0.0/24 is subnetted, 5 subnets
S 10.1.1.0 [150/0] via 10.1.2.1
C 10.1.2.0 is directly connected, Serial0/0/0
C 10.1.3.0 is directly connected, Serial0/0/1
S 10.1.4.0 [150/0] via 10.1.3.1
S 10.1.5.0 [150/0] via 10.1.2.1
172.16.0.0/24 is subnetted, 1 subnets
S 172.16.10.0 [150/0] via 10.1.3.1
C 192.168.10.0/24 is directly connected, FastEthernet0/0
C 192.168.20.0/24 is directly connected, FastEthernet0/1
S 192.168.30.0/24 [150/0] via 10.1.3.1
S 192.168.40.0/24 [150/0] via 10.1.2.1
These RIP routes are being advertised as available *to other RIP routers*.
CORP is advertisting THREE routes via RIP to R1 right now
10.1.1.0
10.1.4.0
10.1.5.0
access to those networks can be achieved by R1 by going THROUGH CORP via ingress .2.1 or .3.1
The advantage..... is that we didnt statically program these routes
we engaged RIP, on BOTH routers- R1 and Corp, and handed them BOTH the network "10.0.0.0"
So, why did RIP choose to display these particular routes
Keep in mind that the output above is from R1 only... In the context of the R1 ROUTER ONLY,
there are three relevant routes within the "10.0.0.0" parameter we specified. The three routes involve Corp.
Corp is sending RIP data about these routes to Corp.
Lets look closer at how this is happening:
here's our starting point before any RIP is set
here's our routing tables after i set RIP with 10.0.0.0 on both..
FIRST i set it on Corp, then R1.(per the book's instructions) As a result we are seeing RIP routes in R1 only....
then I went back to a fresh packet tracer file with no RIP set. And I set RIP in the opposite order;
FIRST i set it on R1, then Corp. And again, we are seeing RIP routes in R1 only....
I wanted to prove that it didnt matter which order we enabled RIP on the two routers. What matters here is that
we enable RIP on both of them with the criteria of 10.0.0.0
Recall the topology:
if Corp and R1 are set for RIP and given the criteria 10.0.0.0, meaning that we are trying to reach networks
within that range, then it follows that Corp will advertise 1.1.0, 1.4.0, and 1.5.0 to R1, because Corp stands between those networks
and R1
"Hi R1, I'm Corp I have three networks that fall inside 10.0.0.0, and you can reach them through me via .2.1 or .3.1"
It also follows that Corp's routing table shows no RIP routes- because R1 isnt advertising any. R1 doesnt have any networks
in the 10.0.0.0 range that Corp could reach
To further clarify this, we'll proceed with the book's instructions. We'll now set more RIP routes on R1
R1(config)#
router rip
R1(config-router)#
network 192.168.10.0
R1(config-router)#
network 192.168.20.0
Corp routing table before RIP set on R1:
Corp#
show ip route
10.0.0.0/8 is variably subnetted, 10 subnets, 2 masks
C 10.1.1.0/24 is directly connected, Vlan1
L 10.1.1.1/32 is directly connected, Vlan1
C 10.1.2.0/24 is directly connected, Serial0/0/0
L 10.1.2.1/32 is directly connected, Serial0/0/0
C 10.1.3.0/24 is directly connected, Serial0/0/1
L 10.1.3.1/32 is directly connected, Serial0/0/1
C 10.1.4.0/24 is directly connected, Serial0/1/0
L 10.1.4.1/32 is directly connected, Serial0/1/0
C 10.1.5.0/24 is directly connected, FastEthernet0/0
L 10.1.5.1/32 is directly connected, FastEthernet0/0
172.16.0.0/24 is subnetted, 1 subnets
S 172.16.10.0/24 [150/0] via 10.1.5.2
S 192.168.10.0/24 [150/0] via 10.1.2.2
S 192.168.20.0/24 [150/0] via 10.1.3.2
S 192.168.30.0/24 [150/0] via 10.1.4.2
S 192.168.40.0/24 [150/0] via 10.1.4.2
Corp routing table after RIP set on R1:
Gateway of last resort is not set
10.0.0.0/8 is variably subnetted, 10 subnets, 2 masks
C 10.1.1.0/24 is directly connected, Vlan1
L 10.1.1.1/32 is directly connected, Vlan1
C 10.1.2.0/24 is directly connected, Serial0/0/0
L 10.1.2.1/32 is directly connected, Serial0/0/0
C 10.1.3.0/24 is directly connected, Serial0/0/1
L 10.1.3.1/32 is directly connected, Serial0/0/1
C 10.1.4.0/24 is directly connected, Serial0/1/0
L 10.1.4.1/32 is directly connected, Serial0/1/0
C 10.1.5.0/24 is directly connected, FastEthernet0/0
L 10.1.5.1/32 is directly connected, FastEthernet0/0
nothing changed so far
172.16.0.0/24 is subnetted, 1 subnets
S 172.16.10.0/24 [150/0] via 10.1.5.2
no change
R 192.168.10.0/24 [120/1] via 10.1.2.2, 00:00:08, Serial0/0/0
[120/1] via 10.1.3.2, 00:00:08, Serial0/0/1
RIP overrides static- 2 paths available now
R 192.168.20.0/24 [120/1] via 10.1.2.2, 00:00:08, Serial0/0/0
[120/1] via 10.1.3.2, 00:00:08, Serial0/0/1
RIP overrides static- 2 paths available now
S 192.168.30.0/24 [150/0] via 10.1.4.2
no change
S 192.168.40.0/24 [150/0] via 10.1.4.2
no change
"Hi Corp- I'm R1 and I have zero networks
that fall inside 10.0.0.0, however I do have some networks that fall within
192.168.20.0 and 192.168.10.0
and you can reach them through me(R1) if you ingress at .1.2.2 or .1.3.2"
ok, we have the concept down. Time to proceed and set up RIP on R2............
R2(config)#
router rip
R2(config-router)#
network 10.0.0.0
R2(config-router)#
network 192.168.30.0
R2(config-router)#
network 192.168.40.0
R2 before RIP enabled
R2#
show ip route
10.0.0.0/24 is subnetted, 5 subnets
S 10.1.1.0 [150/0] via 10.1.4.1
S 10.1.2.0 [150/0] via 10.1.4.1
S 10.1.3.0 [150/0] via 10.1.4.1
C 10.1.4.0 is directly connected, Serial0/0/0
S 10.1.5.0 [150/0] via 10.1.4.1
172.16.0.0/24 is subnetted, 1 subnets
S 172.16.10.0 [150/0] via 10.1.4.1
S 192.168.10.0/24 [150/0] via 10.1.4.1
S 192.168.20.0/24 [150/0] via 10.1.4.1
C 192.168.30.0/24 is directly connected, FastEthernet0/0
C 192.168.40.0/24 is directly connected, FastEthernet0/1
R2 after RIP added
R2#
show ip route
10.0.0.0/24 is subnetted, 5 subnets
R 10.1.1.0 [120/1] via 10.1.4.1, 00:00:24, Serial0/0/0
from corp
R 10.1.2.0 [120/1] via 10.1.4.1, 00:00:24, Serial0/0/0
from corp
R 10.1.3.0 [120/1] via 10.1.4.1, 00:00:24, Serial0/0/0
from corp
C 10.1.4.0 is directly connected, Serial0/0/0
R 10.1.5.0 [120/1] via 10.1.4.1, 00:00:24, Serial0/0/0
from corp
172.16.0.0/24 is subnetted, 1 subnets
S 172.16.10.0 [150/0] via 10.1.4.1
R 192.168.10.0/24 [120/2] via 10.1.4.1, 00:00:24, Serial0/0/0
from R1 via corp
R 192.168.20.0/24 [120/2] via 10.1.4.1, 00:00:24, Serial0/0/0
from R1 via corp
C 192.168.30.0/24 is directly connected, FastEthernet0/0
C 192.168.40.0/24 is directly connected, FastEthernet0/1
now lets compare the Corp and R1 routing tables- before RIP was set on R2 and after
Corp before R2 RIP
Corp#
show ip route
10.0.0.0/8 is variably subnetted, 10 subnets, 2 masks
C 10.1.1.0/24 is directly connected, Vlan1
L 10.1.1.1/32 is directly connected, Vlan1
C 10.1.2.0/24 is directly connected, Serial0/0/0
L 10.1.2.1/32 is directly connected, Serial0/0/0
C 10.1.3.0/24 is directly connected, Serial0/0/1
L 10.1.3.1/32 is directly connected, Serial0/0/1
C 10.1.4.0/24 is directly connected, Serial0/1/0
L 10.1.4.1/32 is directly connected, Serial0/1/0
C 10.1.5.0/24 is directly connected, FastEthernet0/0
L 10.1.5.1/32 is directly connected, FastEthernet0/0
172.16.0.0/24 is subnetted, 1 subnets
S 172.16.10.0/24 [150/0] via 10.1.5.2
R 192.168.10.0/24 [120/1] via 10.1.2.2, 00:00:02, Serial0/0/0
[120/1] via 10.1.3.2, 00:00:02, Serial0/0/1
R 192.168.20.0/24 [120/1] via 10.1.2.2, 00:00:02, Serial0/0/0
[120/1] via 10.1.3.2, 00:00:02, Serial0/0/1
from R1
S 192.168.30.0/24 [150/0] via 10.1.4.2
S 192.168.40.0/24 [150/0] via 10.1.4.2
Corp after R2 RIP
Corp#
show ip route
10.0.0.0/8 is variably subnetted, 10 subnets, 2 masks
C 10.1.1.0/24 is directly connected, Vlan1
L 10.1.1.1/32 is directly connected, Vlan1
C 10.1.2.0/24 is directly connected, Serial0/0/0
L 10.1.2.1/32 is directly connected, Serial0/0/0
C 10.1.3.0/24 is directly connected, Serial0/0/1
L 10.1.3.1/32 is directly connected, Serial0/0/1
C 10.1.4.0/24 is directly connected, Serial0/1/0
L 10.1.4.1/32 is directly connected, Serial0/1/0
C 10.1.5.0/24 is directly connected, FastEthernet0/0
L 10.1.5.1/32 is directly connected, FastEthernet0/0
172.16.0.0/24 is subnetted, 1 subnets
S 172.16.10.0/24 [150/0] via 10.1.5.2
R 192.168.10.0/24 [120/1] via 10.1.2.2, 00:00:19, Serial0/0/0
[120/1] via 10.1.3.2, 00:00:19, Serial0/0/1
R 192.168.20.0/24 [120/1] via 10.1.2.2, 00:00:19, Serial0/0/0
[120/1] via 10.1.3.2, 00:00:19, Serial0/0/1
from R1
R 192.168.30.0/24 [120/1] via 10.1.4.2, 00:00:15, Serial0/1/0
R 192.168.40.0/24 [120/1] via 10.1.4.2, 00:00:15, Serial0/1/0
from R2
RIP on R2 is advertising .30.0 and .40.0 to Corp
R1 before R2 RIP
R1#
show ip route
10.0.0.0/24 is subnetted, 5 subnets
R 10.1.1.0 [120/1] via 10.1.2.1, 00:00:05, Serial0/0/0
[120/1] via 10.1.3.1, 00:00:05, Serial0/0/1
from Corp
C 10.1.2.0 is directly connected, Serial0/0/0
C 10.1.3.0 is directly connected, Serial0/0/1
R 10.1.4.0 [120/1] via 10.1.2.1, 00:00:05, Serial0/0/0
[120/1] via 10.1.3.1, 00:00:05, Serial0/0/1
R 10.1.5.0 [120/1] via 10.1.2.1, 00:00:05, Serial0/0/0
[120/1] via 10.1.3.1, 00:00:05, Serial0/0/1
from Corp
172.16.0.0/24 is subnetted, 1 subnets
S 172.16.10.0 [150/0] via 10.1.3.1
C 192.168.10.0/24 is directly connected, FastEthernet0/0
C 192.168.20.0/24 is directly connected, FastEthernet0/1
S 192.168.30.0/24 [150/0] via 10.1.3.1
S 192.168.40.0/24 [150/0] via 10.1.2.1
R1 after R2 RIP
R1#
show ip route
10.0.0.0/24 is subnetted, 5 subnets
R 10.1.1.0 [120/1] via 10.1.2.1, 00:00:06, Serial0/0/0
[120/1] via 10.1.3.1, 00:00:06, Serial0/0/1
from Corp
C 10.1.2.0 is directly connected, Serial0/0/0
C 10.1.3.0 is directly connected, Serial0/0/1
R 10.1.4.0 [120/1] via 10.1.2.1, 00:00:06, Serial0/0/0
[120/1] via 10.1.3.1, 00:00:06, Serial0/0/1
R 10.1.5.0 [120/1] via 10.1.2.1, 00:00:06, Serial0/0/0
[120/1] via 10.1.3.1, 00:00:06, Serial0/0/1
from Corp
172.16.0.0/24 is subnetted, 1 subnets
S 172.16.10.0 [150/0] via 10.1.3.1
C 192.168.10.0/24 is directly connected, FastEthernet0/0
C 192.168.20.0/24 is directly connected, FastEthernet0/1
R 192.168.30.0/24 [120/2] via 10.1.3.1, 00:00:06, Serial0/0/1
[120/2] via 10.1.2.1, 00:00:06, Serial0/0/0
R 192.168.40.0/24 [120/2] via 10.1.2.1, 00:00:06, Serial0/0/0
[120/2] via 10.1.3.1, 00:00:06, Serial0/0/1
from R2 via Corp
Now to set RIP on R3
R3(config)#
router rip
R3(config-router)#
network 10.0.0.0
R3(config-router)#
network 172.16.0.0
note that R3 is our only router with "gateway of last resort" set because we set a default route instead of static routes
As a result, we only see directly connected routes listed, along with a single "S*" for the default gateway
R3 before RIP
R3#
show ip route
Gateway of last resort is 10.1.5.1 to network 0.0.0.0
10.0.0.0/8 is variably subnetted, 2 subnets, 2 masks
C 10.1.5.0/24 is directly connected, FastEthernet0/0
L 10.1.5.2/32 is directly connected, FastEthernet0/0
172.16.0.0/16 is variably subnetted, 2 subnets, 2 masks
C 172.16.10.0/24 is directly connected, Dot11Radio0/0/0
L 172.16.10.1/32 is directly connected, Dot11Radio0/0/0
S* 0.0.0.0/0 [1/0] via 10.1.5.1
R3 after RIP
R3#
show ip route
Gateway of last resort is 10.1.5.1 to network 0.0.0.0
-------------------------------------------------------------
10.0.0.0/8 is variably subnetted, 6 subnets, 2 masks
R 10.1.1.0/24 [120/1] via 10.1.5.1, 00:00:21, FastEthernet0/0
R 10.1.2.0/24 [120/1] via 10.1.5.1, 00:00:21, FastEthernet0/0
R 10.1.3.0/24 [120/1] via 10.1.5.1, 00:00:21, FastEthernet0/0
R 10.1.4.0/24 [120/1] via 10.1.5.1, 00:00:21, FastEthernet0/0
from Corp
C 10.1.5.0/24 is directly connected, FastEthernet0/0
L 10.1.5.2/32 is directly connected, FastEthernet0/0
-------------------------------------------------------------
172.16.0.0/16 is variably subnetted, 2 subnets, 2 masks
C 172.16.10.0/24 is directly connected, Dot11Radio0/0/0
L 172.16.10.1/32 is directly connected, Dot11Radio0/0/0
R 192.168.10.0/24 [120/2] via 10.1.5.1, 00:00:21, FastEthernet0/0
R 192.168.20.0/24 [120/2] via 10.1.5.1, 00:00:21, FastEthernet0/0
From R1 via Corp
R 192.168.30.0/24 [120/2] via 10.1.5.1, 00:00:21, FastEthernet0/0
R 192.168.40.0/24 [120/2] via 10.1.5.1, 00:00:21, FastEthernet0/0
From R2 via Corp
S* 0.0.0.0/0 [1/0] via 10.1.5.1
Corp before R3 RIP
Corp#
show ip route
10.0.0.0/8 is variably subnetted, 10 subnets, 2 masks
C 10.1.1.0/24 is directly connected, Vlan1
L 10.1.1.1/32 is directly connected, Vlan1
C 10.1.2.0/24 is directly connected, Serial0/0/0
L 10.1.2.1/32 is directly connected, Serial0/0/0
C 10.1.3.0/24 is directly connected, Serial0/0/1
L 10.1.3.1/32 is directly connected, Serial0/0/1
C 10.1.4.0/24 is directly connected, Serial0/1/0
L 10.1.4.1/32 is directly connected, Serial0/1/0
C 10.1.5.0/24 is directly connected, FastEthernet0/0
L 10.1.5.1/32 is directly connected, FastEthernet0/0
172.16.0.0/24 is subnetted, 1 subnets
S 172.16.10.0/24 [150/0] via 10.1.5.2
R 192.168.10.0/24 [120/1] via 10.1.2.2, 00:00:26, Serial0/0/0
[120/1] via 10.1.3.2, 00:00:26, Serial0/0/1
R 192.168.20.0/24 [120/1] via 10.1.2.2, 00:00:26, Serial0/0/0
[120/1] via 10.1.3.2, 00:00:26, Serial0/0/1
from R1 via corp
R 192.168.30.0/24 [120/1] via 10.1.4.2, 00:00:21, Serial0/1/0
R 192.168.40.0/24 [120/1] via 10.1.4.2, 00:00:21, Serial0/1/0
from R2 via corp
Corp after R3 RIP
Corp#
show ip route
10.0.0.0/8 is variably subnetted, 10 subnets, 2 masks
C 10.1.1.0/24 is directly connected, Vlan1
L 10.1.1.1/32 is directly connected, Vlan1
C 10.1.2.0/24 is directly connected, Serial0/0/0
L 10.1.2.1/32 is directly connected, Serial0/0/0
C 10.1.3.0/24 is directly connected, Serial0/0/1
L 10.1.3.1/32 is directly connected, Serial0/0/1
C 10.1.4.0/24 is directly connected, Serial0/1/0
L 10.1.4.1/32 is directly connected, Serial0/1/0
C 10.1.5.0/24 is directly connected, FastEthernet0/0
L 10.1.5.1/32 is directly connected, FastEthernet0/0
172.16.0.0/16 is variably subnetted, 2 subnets, 2 masks
R 172.16.0.0/16 [120/1] via 10.1.5.2, 00:00:13, FastEthernet0/0
S 172.16.10.0/24 [150/0] via 10.1.5.2
from R3
R 192.168.10.0/24 [120/1] via 10.1.3.2, 00:00:13, Serial0/0/1
[120/1] via 10.1.2.2, 00:00:13, Serial0/0/0
R 192.168.20.0/24 [120/1] via 10.1.3.2, 00:00:13, Serial0/0/1
[120/1] via 10.1.2.2, 00:00:13, Serial0/0/0
from R1 via corp
R 192.168.30.0/24 [120/1] via 10.1.4.2, 00:00:24, Serial0/1/0
R 192.168.40.0/24 [120/1] via 10.1.4.2, 00:00:24, Serial0/1/0
from R2 via corp
R2 before R3 RIP
R2#
show ip route
10.0.0.0/24 is subnetted, 5 subnets
R 10.1.1.0 [120/1] via 10.1.4.1, 00:00:15, Serial0/0/0
R 10.1.2.0 [120/1] via 10.1.4.1, 00:00:15, Serial0/0/0
R 10.1.3.0 [120/1] via 10.1.4.1, 00:00:15, Serial0/0/0
from Corp
C 10.1.4.0 is directly connected, Serial0/0/0
R 10.1.5.0 [120/1] via 10.1.4.1, 00:00:15, Serial0/0/0
from Corp
172.16.0.0/24 is subnetted, 1 subnets
S 172.16.10.0 [150/0] via 10.1.4.1
R 192.168.10.0/24 [120/2] via 10.1.4.1, 00:00:15, Serial0/0/0
R 192.168.20.0/24 [120/2] via 10.1.4.1, 00:00:15, Serial0/0/0
from R1 via Corp
C 192.168.30.0/24 is directly connected, FastEthernet0/0
C 192.168.40.0/24 is directly connected, FastEthernet0/1
R2 after R3 RIP
R2#
show ip route
10.0.0.0/24 is subnetted, 5 subnets
R 10.1.1.0 [120/1] via 10.1.4.1, 00:00:20, Serial0/0/0
R 10.1.2.0 [120/1] via 10.1.4.1, 00:00:20, Serial0/0/0
R 10.1.3.0 [120/1] via 10.1.4.1, 00:00:20, Serial0/0/0
from Corp
C 10.1.4.0 is directly connected, Serial0/0/0
R 10.1.5.0 [120/1] via 10.1.4.1, 00:00:20, Serial0/0/0
from Corp
172.16.0.0/16 is variably subnetted, 2 subnets, 2 masks
R 172.16.0.0/16 [120/2] via 10.1.4.1, 00:00:20, Serial0/0/0
S 172.16.10.0/24 [150/0] via 10.1.4.1
from R3 via Corp
R 192.168.10.0/24 [120/2] via 10.1.4.1, 00:00:20, Serial0/0/0
R 192.168.20.0/24 [120/2] via 10.1.4.1, 00:00:20, Serial0/0/0
from R1 via Corp
C 192.168.30.0/24 is directly connected, FastEthernet0/0
C 192.168.40.0/24 is directly connected, FastEthernet0/1
R1 before R3 RIP
R1#
show ip route
10.0.0.0/24 is subnetted, 5 subnets
R 10.1.1.0 [120/1] via 10.1.2.1, 00:00:04, Serial0/0/0
[120/1] via 10.1.3.1, 00:00:04, Serial0/0/1
C 10.1.2.0 is directly connected, Serial0/0/0
C 10.1.3.0 is directly connected, Serial0/0/1
R 10.1.4.0 [120/1] via 10.1.2.1, 00:00:04, Serial0/0/0
[120/1] via 10.1.3.1, 00:00:04, Serial0/0/1
R 10.1.5.0 [120/1] via 10.1.2.1, 00:00:04, Serial0/0/0
[120/1] via 10.1.3.1, 00:00:04, Serial0/0/1
from Corp
172.16.0.0/24 is subnetted, 1 subnets
S 172.16.10.0 [150/0] via 10.1.3.1
C 192.168.10.0/24 is directly connected, FastEthernet0/0
C 192.168.20.0/24 is directly connected, FastEthernet0/1
R 192.168.30.0/24 [120/2] via 10.1.2.1, 00:00:04, Serial0/0/0
[120/2] via 10.1.3.1, 00:00:04, Serial0/0/1
R 192.168.40.0/24 [120/2] via 10.1.2.1, 00:00:04, Serial0/0/0
[120/2] via 10.1.3.1, 00:00:04, Serial0/0/1
from R2 via Corp
R1 after R3 RIP
R1#
show ip route
10.0.0.0/24 is subnetted, 5 subnets
R 10.1.1.0 [120/1] via 10.1.3.1, 00:00:03, Serial0/0/1
[120/1] via 10.1.2.1, 00:00:03, Serial0/0/0
C 10.1.2.0 is directly connected, Serial0/0/0
C 10.1.3.0 is directly connected, Serial0/0/1
R 10.1.4.0 [120/1] via 10.1.3.1, 00:00:03, Serial0/0/1
[120/1] via 10.1.2.1, 00:00:03, Serial0/0/0
R 10.1.5.0 [120/1] via 10.1.3.1, 00:00:03, Serial0/0/1
[120/1] via 10.1.2.1, 00:00:03, Serial0/0/0
from Corp
172.16.0.0/16 is variably subnetted, 2 subnets, 2 masks
R 172.16.0.0/16 [120/2] via 10.1.3.1, 00:00:03, Serial0/0/1
[120/2] via 10.1.2.1, 00:00:03, Serial0/0/0
S 172.16.10.0/24 [150/0] via 10.1.3.1
from R3 via Corp
C 192.168.10.0/24 is directly connected, FastEthernet0/0
C 192.168.20.0/24 is directly connected, FastEthernet0/1
R 192.168.30.0/24 [120/2] via 10.1.3.1, 00:00:03, Serial0/0/1
[120/2] via 10.1.2.1, 00:00:03, Serial0/0/0
R 192.168.40.0/24 [120/2] via 10.1.3.1, 00:00:03, Serial0/0/1
[120/2] via 10.1.2.1, 00:00:03, Serial0/0/0
from R2 via Corp
Verifying Configurations
in addition to
show ip route
we can also use
show ip protocols
and
debug rip ip
Corp#
show ip protocols
Routing Protocol is "rip"
Sending updates every 30 seconds, next due in 11 seconds
Invalid after 180 seconds, hold down 180, flushed after 240
Outgoing update filter list for all interfaces is not set
Incoming update filter list for all interfaces is not set
Redistributing: rip
Default version control: send version 1, receive any version
Interface Send Recv Triggered RIP Key-chain
Vlan1 1 2 1
FastEthernet0/0 1 2 1
Serial0/0/1 1 2 1
Serial0/1/0 1 2 1
Serial0/0/0 1 2 1
Automatic network summarization is in effect
Maximum path: 4
Routing for Networks:
10.0.0.0
Passive Interface(s):
Routing Information Sources:
Gateway Distance Last Update
10.1.5.2 120 00:00:00
10.1.3.2 120 00:00:10
10.1.2.2 120 00:00:10
10.1.4.2 120 00:00:20
Distance: (default is 120)
R3#
debug ip rip
R3#RIP: received v1 update from 10.1.5.1 on FastEthernet0/0
10.1.1.0 in 1 hops
10.1.2.0 in 1 hops
10.1.3.0 in 1 hops
10.1.4.0 in 1 hops
192.168.10.0 in 2 hops
192.168.20.0 in 2 hops
192.168.30.0 in 2 hops
192.168.40.0 in 2 hops
R3#RIP: sending v1 update to 255.255.255.255 via Dot11Radio0/0/0 (172.16.10.1)
RIP: build update entries
network 10.0.0.0 metric 1
network 192.168.10.0 metric 3
network 192.168.20.0 metric 3
network 192.168.30.0 metric 3
network 192.168.40.0 metric 3
RIP: sending v1 update to 255.255.255.255 via FastEthernet0/0 (10.1.5.2)
RIP: build update entries
network 172.16.0.0 metric 1
output loops until manually disabled..............
R3#
undebug all
All possible debugging has been turned off
Note that due to the Split Horizon rule, R3 is not sending all of it's known RIP data to Corp.
It is sending all known RIP data out of the wifi interface (even there though there's no router that way),
but it is ONLY sending data about the wifi network back to Corp; data that Corp doesnt already have
Now lets look at some examples with sample routers..
I got hung up on these two examples because I found the
wording to be a bit confusing. Also there was subnetting involved that I was able to figure out, but threw me at first
First source of confusion- we have two seperate examples, and I was mixing them up.
The examples are:
Use the debug ip rip command to both:
discover a problem
and figure out how RIP was configured on a router from a different sample network
The conclusion regarding 'figuring out how RIP is configured' on this router, is that RIP networks are set as 10.0.0.0 and 172.16.0.0.
We determined that we are not the 'first source' of info on the 192.168.1.0 nertwork, since it is a metric of 2. We are sending out RIP data on that network,
but that RIP data is made availbale to us via another router.
I also got tripped up on the fact that RA is sending out S0/0 which corresponds 10.0.8.1,
and then receiving on the same interface S0/0 from an ip address of 10.0.15.0 on the other side of the link
I was able to determine that these two address are actually on the same subnet. My initial assumption was that the network address for the link is 10.0.0.0.
The problem doesn't give the subnet mask- I guessed it as /20 by using a 16 block since we can see that the third octet seems to move in 8's
if the network starts at 10.0.0.0 and we use /20 with 16 block, we would indeed have a last host address of 10.0.15.254, so 10.0.15.2 would be a valid host.
So there was a twist to this problem which needed subnetting to solve. It wasnt particulary releveant to the subject of RIP, but I was curious why the address on
the other side of that link looked so strange.
The problem also points out that we can determine there are 'at least' two routers participating in RIP here since we are sending RIP data out two interfaces but
only receiving RIP data on one interface. I'm unclear on why its worded this way; we know we are a RIP router- the fact that we are receiving data on one interface
would suggest there is 'at least one more' RIP router out there.
that's it for this example. Back to the original statement-
Use the debug ip rip command to both discover a problem and figure out
how RIP was configured on a router from a different sample network
We just 'figured out how RIP was configured on a router'.. The second example is regarding 'discovering a problem', although it is mentioned first.
The second example will use debug ip rip and show ip route to find a problem with the network
it looks like RIP data for 172.16.20.0 was received on S0/0, and then that interface was bumped out of the routing table entry for that network in favor of a static route.
ok, moving on now to RIP V2
RIP V2
enable it on all four routers
Corp(config)
router rip
Corp(config-router)
version 2
R1(config)
router rip
R1(config-router)
version 2
R2(config)
router rip
R2(config-router)
version 2
R3(config)
router rip
R3(config-router)
version 2
We'll use R1 to compare RIPv1 and RIPv2
RIPv1
R1(config)
debug ip rip
R1#RIP: sending v1 update to 255.255.255.255 via FastEthernet0/0 (192.168.10.1)
RIP: build update entries
network 10.0.0.0 metric 1
network 172.16.0.0 metric 3
network 192.168.20.0 metric 1
network 192.168.30.0 metric 3
network 192.168.40.0 metric 3
RIP: sending v1 update to 255.255.255.255 via FastEthernet0/1 (192.168.20.1)
RIP: build update entries
network 10.0.0.0 metric 1
network 172.16.0.0 metric 3
network 192.168.10.0 metric 1
network 192.168.30.0 metric 3
network 192.168.40.0 metric 3
RIP: sending v1 update to 255.255.255.255 via Serial0/0/0 (10.1.2.2)
RIP: build update entries
network 10.1.3.0 metric 1
network 192.168.10.0 metric 1
network 192.168.20.0 metric 1
RIP: sending v1 update to 255.255.255.255 via Serial0/0/1 (10.1.3.2)
RIP: build update entries
network 10.1.2.0 metric 1
network 192.168.10.0 metric 1
network 192.168.20.0 metric 1
RIPv2
R1(config)
debug ip rip
R1#RIP: sending v2 update to 224.0.0.9 via FastEthernet0/0 (192.168.10.1)
RIP: build update entries
10.0.0.0/8 via 0.0.0.0, metric 1, tag 0
172.16.0.0/16 via 0.0.0.0, metric 3, tag 0
192.168.20.0/24 via 0.0.0.0, metric 1, tag 0
192.168.30.0/24 via 0.0.0.0, metric 3, tag 0
192.168.40.0/24 via 0.0.0.0, metric 3, tag 0
RIP: sending v2 update to 224.0.0.9 via FastEthernet0/1 (192.168.20.1)
RIP: build update entries
10.0.0.0/8 via 0.0.0.0, metric 1, tag 0
172.16.0.0/16 via 0.0.0.0, metric 3, tag 0
192.168.10.0/24 via 0.0.0.0, metric 1, tag 0
192.168.30.0/24 via 0.0.0.0, metric 3, tag 0
192.168.40.0/24 via 0.0.0.0, metric 3, tag 0
RIP: sending v2 update to 224.0.0.9 via Serial0/0/0 (10.1.2.2)
RIP: build update entries
10.1.3.0/24 via 0.0.0.0, metric 1, tag 0
192.168.10.0/24 via 0.0.0.0, metric 1, tag 0
192.168.20.0/24 via 0.0.0.0, metric 1, tag 0
RIP: sending v2 update to 224.0.0.9 via Serial0/0/1 (10.1.3.2)
RIP: build update entries
10.1.2.0/24 via 0.0.0.0, metric 1, tag 0
192.168.10.0/24 via 0.0.0.0, metric 1, tag 0
192.168.20.0/24 via 0.0.0.0, metric 1, tag 0
R1(config)
show ip protocols
Routing Protocol is "rip"
Sending updates every 30 seconds, next due in 13 seconds
Invalid after 180 seconds, hold down 180, flushed after 240
Outgoing update filter list for all interfaces is not set
Incoming update filter list for all interfaces is not set
Redistributing: rip
Default version control: send version 2, receive 2
Interface Send Recv Triggered RIP Key-chain
FastEthernet0/0 2 2
FastEthernet0/1 2 2
Serial0/0/0 2 2
Serial0/0/1 2 2
Automatic network summarization is in effect
Maximum path: 4
Routing for Networks:
10.0.0.0
192.168.10.0
192.168.20.0
Passive Interface(s):
Routing Information Sources:
Gateway Distance Last Update
10.1.3.1 120 00:00:21
10.1.2.1 120 00:00:21
Distance: (default is 120)
final task of this chapter
Enable a default route out to the internet , and advertise via RIP
R3(config)#
interface s0/1/0 (this is only for example, so I am not adding a serial card to R3)
R3(config-if)#
ip addr 172.16.10.5 255.255.255.252
R3(config-if)#
exit
R3(config)#
ip route 0.0.0.0 0.0.0.0 s0/0
R3(config)#
ip default-network 172.16.0.0 tells other routers via RIP that default WAN route is through R3
Chapter 8 Exam Essentials IP Routing
1. Describe the Basic IP routing process
frame changes at each hop, but packet doesnt change EXCEPT that the TTL field in the IP header decrements
2. List the information required by a router to successfully route packets
destination IP address, location of other routers, possible routers to all remote networks,
the best route to each network, how to maintain and maintain routing info
3. Describe how MAC addresses are used during the routing process
a MAC will never pass a router interface. MACs will change between router interfaces
4. View and interpret the routing table of a router
use show ip route to see the table
a "C" indicates directly connected, an "R" indicates RIP provided the route info, "S" means static
5. differentiate the three types of routing
static- manually configured
dynamic- routers automatically share info via protocol
default- a special route is configured for all traffic without a more specific destination network found in the table
6. Compare and contrast static and dynamic routing
static routing creates no routing update traffic which means less overhead on the routers and links- but it must be
configured manually and can't react if links are lost.
dynamic routing creates update traffic, but it can react to outages and choose the best route when multiple routes exist to the same network
7. Configure static routes at the CLI
route [dest network] [mask] [next hop address OR exit interface] [admin distance] [permanent]
Ex:
Corp(config)#
ip route 192.168.10.0 255.255.255.0 10.1.2.2 150
8. Create a default route
ip route 0.0.0.0 0.0.0.0 [ip address OR exit interface]
Ex:
R3(config)#
ip route 0.0.0.0 0.0.0.0 10.1.5.1 (ingress at Corp router- use if R3 cant identify route)
9. Understand administrative distance and its role in the selection of the best route
an integer from 0 (most trusted) to 255 (no traffic will pass via this route).
All routing protocols are assigned an AD but it can be changed at the CLI
10. Differentiate distance-vector, link-state, and hybrid routing protocols
distance vector- based on hop count (RIP)
link-state- multiple factors such as bandwidth and delay
hybrid- uses both
11. List mechanisms used to prevent routing loops in the network
max hop count, split horizon, route poisoning, holddown counters
12. Describe the counts used the operation of RIP
route update timer- (30) interval between routing updates
route invalid timer- (180, update x 3) before a route is determined invalid
holddown timer-(180) time info is supressed when a link is lost
route flush timer- (240) seconds before invalid and removal
13. Configure RIP routing
router rip
network x.x.x.x
the network(s) you want to advertise from your router. It only works if the other router has RIP enabled.
By enabling RIP, you are able to RECEIVE RIP data from other RIP routers.
by specifying a network, you are SENDING RIP data on that network
14. Identify commands used to verify RIP routing
show ip route will provide contents of the routing table with codes (R, C, S)
debug ip rip will show RIP updates being sent and received
15. Describe the differences between RIPv1 and RIPv2
RIPv1 sends a broadcast (255.255.255.255) every 30 seconds and has an AD of 120.
RIPv1 is classful only, does not send any mask info. No authentication between routers.
RIPv2 sends multicasts (224.0.0.9) every 30 seconds and sends mask info, which allows it to support classless networking, RIPv2 also supports
autentication between routers.
Chapter 8 Written Lab 8.0
1. At the appropriate prompt, create a static route to network 172.16.10.0/24 with a next-hop
gateway of 172.16.20.1 and an administrative distance of 150.
Router(config)#
ip route 172.16.10.0 255.255.255.0 172.16.20.1 150
2. When a PC sends a packet to another PC in a remote network, what destination IP address and MAC address will
be in the frame that it sends to it's default gateway?
the gateway interface MAC and the remote PC's IP
3. At the appropriate prompt, create a default route to 172.16.40.1
Router(config)#
ip route 0.0.0.0 0.0.0.0 172.16.40.1
"to" is the wrong word.. we are going TO any route VIA 172.16.40.1
4. If you are using default routing in a classless environment, what command must also be used?
Router(config)#
ip classless
5. On which type of network is a default route most beneficial?
stub
6. At the appropriate prompt, display the routing table on your router
Router#
show ip route
7. When creating a static or default route, you dont have to use the next-hop ip address;
you can instead use the ____________
exit interface
8. True/False: To reach a destination host, you must know the MAC address of the remote host
false, you need the MAC of your router
9. True/False: To reach a destination host, you must know the IP address of the remote host
true
10. At the appropriate prompt, execute the command required on a DCE serial interface that is not required
on a DTE serial interface
Router(config-if)#
clock rate X
11. At the appropriate prompt, enable RIP routing on the interface with the IP address 10.0.0.1/24
Router(config)#
router rip
Router(config-router)#
network 10.0.0.0
RIPv1 is CLASSFUL only... use the classful mask based on the first octet given
12. At the appropriate prompt, prevent a router from propagating IP information out serial 1
Router(config)#
router rip
Router(config-router)#
passive-interface S0/1
can receive RIP data but will not send
13. What routing loop prevention mechanism sends out a maximum hop count as soon as a link fails?
route poisoning
14. What routing loop prevention mechanism suppresses the resending of routing information to an interface
through which it was received?
split horizon
15. At the appropriate prompt display RIP routing updates as they are sent and received on the router
to the console session
Router#
debug ip rip
to turn it off:
Router#
undebug all
Chapter 8 Hands-on Labs
For these labs we will need a network with three routers.
Lab 8.1 Creating Static routes
first set the interfaces, then program the static routes
LabA(config)#
int s0/0/0
LabA(config-if)#
ip addr 172.16.20.1
LabA(config-if)#
int f0/0
LabA(config-if)#
ip addr 172.16.10.1
-----------------------------------------------------------------
LabA(config)#
ip route 172.16.30.0 255.255.255.0 172.16.20.2
LabA(config)#
ip route 172.16.40.0 255.255.255.0 172.16.20.2
LabB(config)#
int s0/0/0
LabB(config-if)#
ip addr 172.16.20.2
LabB(config-if)#
int s0/0/1
LabB(config-if)#
ip addr 172.16.30.1
-----------------------------------------------------------------
LabB(config)#
ip route 172.16.10.0 255.255.255.0 172.16.20.1
LabB(config)#
ip route 172.16.40.0 255.255.255.0 172.16.30.2
LabC(config)#
int s0/0/0
LabC(config-if)#
ip addr 172.16.30.2
LabC(config-if)#
int f0/0
LabC(config-if)#
ip addr 172.16.40.1
-----------------------------------------------------------------
LabC(config)#
ip route 172.16.10.0 255.255.255.0 172.16.30.1
LabC(config)#
ip route 172.16.20.0 255.255.255.0 172.16.30.1
Lab 8.2 RIP Configuration
remove the static routes, enable and configure RIP with the classful network id that covers the routes you want to advertise
LabA(config)#
no ip route 172.16.30.0 255.255.255.0 172.16.20.2
LabA(config)#
no ip route 172.16.40.0 255.255.255.0 172.16.20.2
LabA(config)#
router rip
LabA(config-router)#
network 172.16.0.0
LabA(config-router)#
do show ip route
Gateway of last resort is not set
172.16.0.0/16 is variably subnetted, 5 subnets, 2 masks
C 172.16.10.0/24 is directly connected, FastEthernet0/0
L 172.16.10.1/32 is directly connected, FastEthernet0/0
C 172.16.20.0/24 is directly connected, Serial0/0/0
L 172.16.20.1/32 is directly connected, Serial0/0/0
R 172.16.30.0/24 [120/1] via 172.16.20.2, 00:00:07, Serial0/0/0
from Lab B
LabB(config)#
no ip route 172.16.10.0 255.255.255.0 172.16.20.1
LabB(config)#
no ip route 172.16.40.0 255.255.255.0 172.16.30.2
LabB(config)#
router rip
LabB(config-router)#
network 172.16.0.0
LabB(config-router)#
do show ip route
Gateway of last resort is not set
172.16.0.0/16 is variably subnetted, 5 subnets, 2 masks
R 172.16.10.0/24 [120/1] via 172.16.20.1, 00:00:13, Serial0/0/0
from LabA
C 172.16.20.0/24 is directly connected, Serial0/0/0
L 172.16.20.2/32 is directly connected, Serial0/0/0
C 172.16.30.0/24 is directly connected, Serial0/0/1
L 172.16.30.1/32 is directly connected, Serial0/0/1
LabC(config)#
no ip route 172.16.10.0 255.255.255.0 172.16.30.1
LabC(config)#
no ip route 172.16.20.0 255.255.255.0 172.16.30.1
LabC(config)#
router rip
LabC(config-router)#
network 172.16.0.0
LabC(config-router)#
do show ip route
Gateway of last resort is not set
172.16.0.0/16 is variably subnetted, 3 subnets, 2 masks
R 172.16.20.0/24 [120/1] via 172.16.30.1, 00:00:05, Serial0/0/0
from LabB
C 172.16.30.0/24 is directly connected, Serial0/0/0
L 172.16.30.2/32 is directly connected, Serial0/0/0
Chapter 8 Review Questions
1. The Acme company uses a router named Gateway to connect to its ISP. The address of the ISP router is 206.143.5.2.
Which three commands could be configured on the gateway router to allow internet access to the entire network?
Set a default route:
Gateway(config)#
ip route 0.0.0.0 0.0.0.0 206.143.5.2 next hop IP
Gateway(config)#
ip route 0.0.0.0 0.0.0.0 S/0 exit interface instead of next hop IP
Gateway(config)#
ip default-network 206.143.5.0 next hop IP
2. What command will prevent RIP routing updates from exiting an interface but will sill allow the interface to receive RIP updates?
Router(config-if)#
passive-interface
3. Which two statemnts are true about ip route 172.16.4.0 255.255.255.0 192.168.4.2?
the command establishes a static route
the default admin distance is used (since we didnt give an AD argument)
4. What two destination addresses will be used by HostA to send data to the HTTPS server as shown in the following network?
MAC of RouterA f0/0 interface
IP address of the server
5. Which two statements are true about this output?
RIP: received v1 update from 192.168.40.2 on S0/1
192.168.50.0 in 16 hops (inaccessible)
RIP: sending v1 update to 255.255.255.255 via F0/0 (192.168.30.1)
RIP: build update entries
network 192.168.20.0 metric 1
network 192.168.40.0 metric 1
network 192.168.50.0 metric 16
RIP: sending v1 update to 255.255.255.255 via S0/1 (192.168.40.1)
true:
there are at least two routers exchanging information
192.168.40.2 will be successful
FALSE
there are three interfaces on the router participating in this update
false because we only see two interfaces represented in the output: S0/1(twice) and F0/0
a ping to 192.168.50.1 will be successful
false because that route has a metric of 16; it's unreachable
6. Describe split horizon
will not advertise a route back the the same router it was learned from
7. Which would be true if HostA is trying to communicate to HostB and interface F0/0 of RouterC goes down, as shown in the graphic?
RouterC will send an ICMP 'destination unreachable type' message to inform HostA that HostB is unreachable
8. Which two statements are true regarding classless routing protocols?
VLSM is permitted
RIPv2 supports classless
9. Which two are true regarding distance-vector vs link-state?
Distance vector sends the whole routing table out all active interfaces(even if a router isnt on the other end)at periodic time intervals
Link-state sends updates containing the state of its own links to all routers in the inter-network
10. Which command display RIP routing updates?
debug ip rip
11. What does RIPv2 use to prvent routing loops?
split horizon stops an update from being send on the same interface it was received
holdown timers allow time for a network to become stable in the case of a flapping link
12. A network administrator views the output from the show ip route command. A network that is advertised
by both RIP and EIGRP appears in the routing table flagged an EIGRP route. Why is the RIP route to this network not used in this routing table?
EIGRP has a lower AD.
RIP=120
OSPP=110
IGRP=110
EIGRP=90
13. You type debug ip rip on your router console and see that 172.16.10.0 is being advertised to you with a metric of 16. What does this mean?
it is inaccessible. in RIP if you see a route advertised with a metric of 16, it's inaccessible
14. What metric does RIPv2 use to find the best path to the remote network?
distance aka hop count
15. The Corporate router receives an IP packet with a source IP address of 192.168.214.20 and a destination address of 192.168.22.3. Looking at the output from the Corp router,
what will the router do with this packet?
Corp# show ip route
[cut]
R 192.168.215.0 [120/2] via 192.168.20.2, Serail0/0
R 192.168.115.0 [120/1] via 192.168.20.0, Serial0/0
R 192.168.30.0 [120/1] via 192.168.20.2, Serial0/0
C 192.168.20.0 is directly connected, Serial0/0
C 192.168.214.0 is directly connected, FastEthernet0/0
Since there is no route to that network, the router will discard the packet and send an ICMP destination unreachable message out F0/0 back the the source network
16. If your routing table has a static, a RIP and an EIGRP route to the same network, which route will be used by default?
Static routes have an admin distance of 1 by default. Unless you change it, a static route will always be used over any other
dynamically learned route.
17. You have the following routing table. Which network will NOT be placed in the neighbor routing table?
R 192.168.30.0/24 [120/1] via 192.168.40.1, Serial 0
C 192.168.40.0/24 is directly connected, Serial 0
172.16.0.0/2 is subnetted, 1 subnets
C 172.16.30.0 is directly connected, Loopback0
R 192.168.20.0/24 [120/1] via 192.168.40.1, Serial 0
R 10.0.0.0/8 [120/15] via 192.168.40.1, Serial 0
C 192.168.50.0/24 is directly connected, Ethernet 0
10.0.0.0 cant be placed in neighboring routing table because it is at 15 hops. 16 hops is invalid in RIP
18. Two connected routers are configured only with RIP. What will be the result when a router receives a routing update that contains a
higher-cost path to a network already in it's routing table?
The router will ignore the update because it is higher cost. When a routing update is received, the router first checks the AD and always chooses
the route with the lowest AD.
19.Which is true about route poisoning?
The router sets the metric for a downed link to "infinity".
20. Which is true about RIPv2?
it has all the same timers as RIPv1
------------------------------------------------------------------------------
END CHAPTER 8
54 hours 1-28 thru 2-14-22
original total 143 hours
11.5 hours review 12-23,24,26-22
review total hours 32
book page 428/822
avg 20 min/page (reading and exercises/labs)
Chapter 9 EIGRP and OSPF
pages 427-502, start 2-14-22-M
What is EIGRP?
Note it's not officially on CCNA 200-301 but it is still important to learn
Enhanced IGRP is a classless, enchanced distance vector protocol that uses the concept of an autonomous system to describe
the set of contigous routers that run the same routing protocol and share routing information.
Features:
Support for IP and IPv6 via protocol-dependent modules (seperate routing tables)
Considered classless
Support for summaries and discontiguous networks
Eficient neighbor discovery
communication via RTP- Reliable Transport Protocol
best path selection via Diffusing Updae Algorithm DUAL
Cisco considers EIGRP a "distance-vector" routing protocol
or an "advanced distance-vector" protocol
or a "hybrid" protocol
Configuring EIGRP on our network
------------------------------------------------------------------------------------------------------------------------------------
Corp(config)#
router eigrp ?
<1-65535> Autonomous system number
Corp(config)#
router eigrp 10
R2(config-router)#
network 10.0.0.0
after eigrp on R1- links from Corp to R1 are up
%DUAL-5-NBRCHANGE: IP-EIGRP 10: Neighbor 10.1.3.2 (Serial0/0/1) is up: new adjacency
%DUAL-5-NBRCHANGE: IP-EIGRP 10: Neighbor 10.1.2.2 (Serial0/0/0) is up: new adjacency
after eigrp on R2- link from Corp to R2 is up
%DUAL-5-NBRCHANGE: IP-EIGRP 10: Neighbor 10.1.4.2 (Serial0/1/0) is up: new adjacency
after eigrp on R3- link from Corp to R3 is up
%DUAL-5-NBRCHANGE: IP-EIGRP 10: Neighbor 10.1.5.2 (FastEthernet0/0) is up: new adjacency
------------------------------------------------------------------------------------------------------------------------------------
R1(config)#
router eigrp 10
R1(config-router)#
network 10.0.0.0
after eigrp on R1- link from R1 to Corp is up
%DUAL-5-NBRCHANGE: IP-EIGRP 10: Neighbor 10.1.3.1 (Serial0/0/1) is up: new adjacency
%DUAL-5-NBRCHANGE: IP-EIGRP 10: Neighbor 10.1.2.1 (Serial0/0/0) is up: new adjacency
R1(config-router)#
network 192.168.10.0
R1(config-router)#
network 192.168.20.0
------------------------------------------------------------------------------------------------------------------------------------
R2(config)#
router eigrp 10
R2(config-router)#
network 10.0.0.0
after eigrp on R2- link from R2 to Corp is up
%DUAL-5-NBRCHANGE: IP-EIGRP 10: Neighbor 10.1.4.1 (Serial0/0/0) is up: new adjacency
R1(config-router)#
network 192.168.30.0
R1(config-router)#
network 192.168.40.0
------------------------------------------------------------------------------------------------------------------------------------
R3(config)#
router eigrp 10
R3(config-router)#
network 10.0.0.0
after eigrp on R3- link from R3 to Corp is up
%DUAL-5-NBRCHANGE: IP-EIGRP 10: Neighbor 10.1.5.1 (FastEthernet0/0) is up: new adjacency
R1(config-router)#
network 172.16.0.0
------------------------------------------------------------------------------------------------------------------------------------
Corp#
show ip route
Gateway of last resort is not set
Gateway of last resort is not set
10.0.0.0/8 is variably subnetted, 10 subnets, 2 masks
C 10.1.1.0/24 is directly connected, Vlan1
L 10.1.1.1/32 is directly connected, Vlan1
C 10.1.2.0/24 is directly connected, Serial0/0/0
L 10.1.2.1/32 is directly connected, Serial0/0/0
C 10.1.3.0/24 is directly connected, Serial0/0/1
L 10.1.3.1/32 is directly connected, Serial0/0/1
C 10.1.4.0/24 is directly connected, Serial0/1/0
L 10.1.4.1/32 is directly connected, Serial0/1/0
C 10.1.5.0/24 is directly connected, FastEthernet0/0
L 10.1.5.1/32 is directly connected, FastEthernet0/0
172.16.0.0/16 is variably subnetted, 2 subnets, 2 masks
R 172.16.0.0/16 [120/1] via 10.1.5.2, 00:00:17, FastEthernet0/0
D 172.16.10.0/24 [90/28160] via 10.1.5.2, 00:00:16, FastEthernet0/0
via R3
D 192.168.10.0/24 [90/2172416] via 10.1.2.2, 00:19:13, Serial0/0/0
[90/2172416] via 10.1.3.2, 00:19:13, Serial0/0/1
D 192.168.20.0/24 [90/2172416] via 10.1.3.2, 00:19:05, Serial0/0/1
[90/2172416] via 10.1.2.2, 00:19:05, Serial0/0/0
via R1
D 192.168.30.0/24 [90/2172416] via 10.1.4.2, 00:01:31, Serial0/1/0
D 192.168.40.0/24 [90/2172416] via 10.1.4.2, 00:01:08, Serial0/1/0
via R2
The "D" routes are for DUAL- Diffusing Update Algorithm, indicating they are EIGRP routes.
Note that we have RIP and EIGRP set currently
------------------------------------------------------------------------------------------------------------------------------------
R1#
show ip route
Gateway of last resort is not set
10.0.0.0/8 is variably subnetted, 6 subnets, 2 masks
D 10.0.0.0/8 is a summary, 00:25:28, Null0
D 10.1.1.0/24 [90/27769856] via 10.1.2.1, 00:31:33, Serial0/0/0
[90/27769856] via 10.1.3.1, 00:31:30, Serial0/0/1
via Corp
C 10.1.2.0/24 is directly connected, Serial0/0/0
C 10.1.3.0/24 is directly connected, Serial0/0/1
D 10.1.4.0/24 [90/2681856] via 10.1.2.1, 00:31:33, Serial0/0/0
[90/2681856] via 10.1.3.1, 00:31:30, Serial0/0/1
D 10.1.5.0/24 [90/2172416] via 10.1.2.1, 00:31:33, Serial0/0/0
[90/2172416] via 10.1.3.1, 00:31:30, Serial0/0/1
via Corp
172.16.0.0/16 is variably subnetted, 2 subnets, 2 masks
R 172.16.0.0/16 [120/2] via 10.1.2.1, 00:00:07, Serial0/0/0
[120/2] via 10.1.3.1, 00:00:07, Serial0/0/1
D 172.16.10.0/24 [90/2172416] via 10.1.2.1, 00:06:31, Serial0/0/0
[90/2172416] via 10.1.3.1, 00:06:31, Serial0/0/1
via Corp
C 192.168.10.0/24 is directly connected, FastEthernet0/0
C 192.168.20.0/24 is directly connected, FastEthernet0/1
D 192.168.30.0/24 [90/2684416] via 10.1.3.1, 00:07:46, Serial0/0/1
[90/2684416] via 10.1.2.1, 00:07:46, Serial0/0/0
D 192.168.40.0/24 [90/2684416] via 10.1.2.1, 00:07:23, Serial0/0/0
[90/2684416] via 10.1.3.1, 00:07:23, Serial0/0/1
via Corp
------------------------------------------------------------------------------------------------------------------------------------
R2#
show ip route
Gateway of last resort is not set
10.0.0.0/8 is variably subnetted, 6 subnets, 2 masks
D 10.0.0.0/8 is a summary, 00:13:09, Null0
D 10.1.1.0/24 [90/27769856] via 10.1.4.1, 00:36:53, Serial0/0/0
D 10.1.2.0/24 [90/2681856] via 10.1.4.1, 00:36:53, Serial0/0/0
D 10.1.3.0/24 [90/2681856] via 10.1.4.1, 00:36:53, Serial0/0/0
via Corp
C 10.1.4.0/24 is directly connected, Serial0/0/0
D 10.1.5.0/24 [90/2172416] via 10.1.4.1, 00:36:53, Serial0/0/0
via Corp
172.16.0.0/16 is variably subnetted, 2 subnets, 2 masks
R 172.16.0.0/16 [120/2] via 10.1.4.1, 00:00:23, Serial0/0/0
D 172.16.10.0/24 [90/2172416] via 10.1.4.1, 00:11:54, Serial0/0/0
via Corp
D 192.168.10.0/24 [90/2684416] via 10.1.4.1, 00:30:51, Serial0/0/0
D 192.168.20.0/24 [90/2684416] via 10.1.4.1, 00:30:43, Serial0/0/0
via Corp
C 192.168.30.0/24 is directly connected, FastEthernet0/0
C 192.168.40.0/24 is directly connected, FastEthernet0/1
------------------------------------------------------------------------------------------------------------------------------------
R3#
show ip route
Gateway of last resort is 10.1.5.1 to network 0.0.0.0
10.0.0.0/8 is variably subnetted, 6 subnets, 2 masks
D 10.1.1.0/24 [90/25628160] via 10.1.5.1, 00:37:20, FastEthernet0/0
D 10.1.2.0/24 [90/2172416] via 10.1.5.1, 00:37:15, FastEthernet0/0
D 10.1.3.0/24 [90/2172416] via 10.1.5.1, 00:37:20, FastEthernet0/0
D 10.1.4.0/24 [90/2172416] via 10.1.5.1, 00:37:20, FastEthernet0/0
via Corp
C 10.1.5.0/24 is directly connected, FastEthernet0/0
L 10.1.5.2/32 is directly connected, FastEthernet0/0
172.16.0.0/16 is variably subnetted, 2 subnets, 2 masks
C 172.16.10.0/24 is directly connected, Dot11Radio0/0/0
L 172.16.10.1/32 is directly connected, Dot11Radio0/0/0
D 192.168.10.0/24 [90/2174976] via 10.1.5.1, 00:31:10, FastEthernet0/0
D 192.168.20.0/24 [90/2174976] via 10.1.5.1, 00:31:02, FastEthernet0/0
via Corp and R1
D 192.168.30.0/24 [90/2174976] via 10.1.5.1, 00:13:28, FastEthernet0/0
D 192.168.40.0/24 [90/2174976] via 10.1.5.1, 00:13:05, FastEthernet0/0
via Corp and R2
S* 0.0.0.0/0 [1/0] via 10.1.5.1
------------------------------------------------------------------------------------------------------------------------------------
turn off auto summary on each router
------------------------------------------------------------------------------------------------------------------------------------
Corp(config)#
router eigrp 10
Corp(config-router)#
no auto-summary
------------------------------------------------------------------------------------------------------------------------------------
R1(config)#
router eigrp 10
R1(config-router)#
no auto-summary
------------------------------------------------------------------------------------------------------------------------------------
R2(config)#
router eigrp 10
R2(config-router)#
no auto-summary
------------------------------------------------------------------------------------------------------------------------------------
R3(config)#
router eigrp 10
R3(config-router)#
no auto-summary
------------------------------------------------------------------------------------------------------------------------------------
compare Corp before and after auto summary turned off
------------------------------------------------------------------------------------------------------------------------------------
auto summary on
Corp#
show ip route
Gateway of last resort is not set
10.0.0.0/8 is variably subnetted, 10 subnets, 2 masks
C 10.1.1.0/24 is directly connected, Vlan1
L 10.1.1.1/32 is directly connected, Vlan1
C 10.1.2.0/24 is directly connected, Serial0/0/0
L 10.1.2.1/32 is directly connected, Serial0/0/0
C 10.1.3.0/24 is directly connected, Serial0/0/1
L 10.1.3.1/32 is directly connected, Serial0/0/1
C 10.1.4.0/24 is directly connected, Serial0/1/0
L 10.1.4.1/32 is directly connected, Serial0/1/0
C 10.1.5.0/24 is directly connected, FastEthernet0/0
L 10.1.5.1/32 is directly connected, FastEthernet0/0
172.16.0.0/16 is variably subnetted, 2 subnets, 2 masks
R 172.16.0.0/16 [120/1] via 10.1.5.2, 00:00:17, FastEthernet0/0
D 172.16.10.0/24 [90/28160] via 10.1.5.2, 00:00:16, FastEthernet0/0
via R3
D 192.168.10.0/24 [90/2172416] via 10.1.2.2, 00:19:13, Serial0/0/0
[90/2172416] via 10.1.3.2, 00:19:13, Serial0/0/1
D 192.168.20.0/24 [90/2172416] via 10.1.3.2, 00:19:05, Serial0/0/1
[90/2172416] via 10.1.2.2, 00:19:05, Serial0/0/0
via R1
D 192.168.30.0/24 [90/2172416] via 10.1.4.2, 00:01:31, Serial0/1/0
D 192.168.40.0/24 [90/2172416] via 10.1.4.2, 00:01:08, Serial0/1/0
via R2
auto summary off
Corp#
show ip route
Gateway of last resort is not set
10.0.0.0/8 is variably subnetted, 10 subnets, 2 masks
C 10.1.1.0/24 is directly connected, Vlan1
L 10.1.1.1/32 is directly connected, Vlan1
C 10.1.2.0/24 is directly connected, Serial0/0/0
L 10.1.2.1/32 is directly connected, Serial0/0/0
C 10.1.3.0/24 is directly connected, Serial0/0/1
L 10.1.3.1/32 is directly connected, Serial0/0/1
C 10.1.4.0/24 is directly connected, Serial0/1/0
L 10.1.4.1/32 is directly connected, Serial0/1/0
C 10.1.5.0/24 is directly connected, FastEthernet0/0
L 10.1.5.1/32 is directly connected, FastEthernet0/0
172.16.0.0/16 is variably subnetted, 2 subnets, 2 masks
R 172.16.0.0/16 [120/1] via 10.1.5.2, 00:00:12, FastEthernet0/0
D 172.16.10.0/24 [90/28160] via 10.1.5.2, 00:45:29, FastEthernet0/0
via R3
D 192.168.10.0/24 [90/2172416] via 10.1.2.2, 00:01:08, Serial0/0/0
[90/2172416] via 10.1.3.2, 00:01:08, Serial0/0/1
D 192.168.20.0/24 [90/2172416] via 10.1.2.2, 00:01:08, Serial0/0/0
[90/2172416] via 10.1.3.2, 00:01:08, Serial0/0/1
via R1
D 192.168.30.0/24 [90/2172416] via 10.1.4.2, 00:00:46, Serial0/1/0
D 192.168.40.0/24 [90/2172416] via 10.1.4.2, 00:00:46, Serial0/1/0
via R2
We are still seeing an auto summarized route- 172.16.0.0 coming from R3.
The book discusses enabling EIGRP auto summary on all four routers- nothing is said about disabling it within RIP or turning off RIP.
RIP auto summarizes by default. We cant get rid of this auto summary route while RIP is on.
Moving on...
VERIFYING EIGRP
several commands available to verify and troubleshoot
show ip route
show the entire routing table
show ip route eigrp
show only EIGRP entries in the routing table
show ip eigrp neighbors
show all EIGRP neigbors
show ip eigrp topology
show entries in the EIGRP topology table
show ip protocols
shows routing protocols configuration
debug eigrp packet
shows hello packets sent/received between adjacent routers
debug ip eigrp events
shows EIGRP changes and updates as they occur on your network
lets take a look at the state of our 4 routers. RIP and EIGRP are running on each.
Notice how this command is giving different outputs between the two different IOS versions
IOS 15.1
Corp#
show ip protocols
Routing Protocol is "eigrp 10 "
Outgoing update filter list for all interfaces is not set
Incoming update filter list for all interfaces is not set
Default networks flagged in outgoing updates
Default networks accepted from incoming updates
Redistributing: eigrp 10
EIGRP-IPv4 Protocol for AS(10)
Metric weight K1=1, K2=0, K3=1, K4=0, K5=0
NSF-aware route hold timer is 240
Router-ID: 10.1.1.1
Topology : 0 (base)
Active Timer: 3 min
Distance: internal 90 external 170
Maximum path: 4
Maximum hopcount 100
Maximum metric variance 1
Automatic Summarization: disabled
Automatic address summarization:
Maximum path: 4
Routing for Networks:
10.0.0.0
Routing Information Sources:
Gateway Distance Last Update
10.1.5.2 90 0
10.1.3.2 90 6464
10.1.2.2 90 6795
10.1.4.2 90 7955
Distance: internal 90 external 170
Routing Protocol is "rip"
Sending updates every 30 seconds, next due in 10 seconds
Invalid after 180 seconds, hold down 180, flushed after 240
Outgoing update filter list for all interfaces is not set
Incoming update filter list for all interfaces is not set
Redistributing: rip
Default version control: send version 2, receive 2
Interface Send Recv Triggered RIP Key-chain
Vlan1 2 2
FastEthernet0/0 2 2
Serial0/1/0 2 2
Serial0/0/1 2 2
Serial0/0/0 2 2
Automatic network summarization is in effect
Maximum path: 4
Routing for Networks:
10.0.0.0
Passive Interface(s):
Routing Information Sources:
Gateway Distance Last Update
10.1.5.2 120 00:00:12
10.1.3.2 120 00:00:16
10.1.2.2 120 00:00:16
10.1.4.2 120 00:00:13
Distance: (default is 120)
IOS 12.4
R1#
show ip protocols
Routing Protocol is "eigrp 10 "
Outgoing update filter list for all interfaces is not set
Incoming update filter list for all interfaces is not set
Default networks flagged in outgoing updates
Default networks accepted from incoming updates
EIGRP metric weight K1=1, K2=0, K3=1, K4=0, K5=0
EIGRP maximum hopcount 100
EIGRP maximum metric variance 1
Redistributing: eigrp 10
Automatic network summarization is not in effect
Maximum path: 4
Routing for Networks:
10.0.0.0
192.168.10.0
192.168.20.0
Routing Information Sources:
Gateway Distance Last Update
10.1.3.1 90 6465
10.1.2.1 90 6794
Distance: internal 90 external 170
Routing Protocol is "rip"
Sending updates every 30 seconds, next due in 21 seconds
Invalid after 180 seconds, hold down 180, flushed after 240
Outgoing update filter list for all interfaces is not set
Incoming update filter list for all interfaces is not set
Redistributing: rip
Default version control: send version 2, receive 2
Interface Send Recv Triggered RIP Key-chain
FastEthernet0/0 2 2
FastEthernet0/1 2 2
Serial0/0/0 2 2
Serial0/0/1 2 2
Automatic network summarization is not in effect
Maximum path: 4
Routing for Networks:
10.0.0.0
192.168.10.0
192.168.20.0
Passive Interface(s):
Routing Information Sources:
Gateway Distance Last Update
10.1.3.1 120 00:00:06
10.1.2.1 120 00:00:06
Distance: (default is 120)
IOS 12.4
R2#
show ip protocols
Routing Protocol is "eigrp 10 "
Outgoing update filter list for all interfaces is not set
Incoming update filter list for all interfaces is not set
Default networks flagged in outgoing updates
Default networks accepted from incoming updates
EIGRP metric weight K1=1, K2=0, K3=1, K4=0, K5=0
EIGRP maximum hopcount 100
EIGRP maximum metric variance 1
Redistributing: eigrp 10
Automatic network summarization is not in effect
Maximum path: 4
Routing for Networks:
10.0.0.0
192.168.30.0
192.168.40.0
Routing Information Sources:
Gateway Distance Last Update
10.1.4.1 90 7955
Distance: internal 90 external 170
Routing Protocol is "rip"
Sending updates every 30 seconds, next due in 11 seconds
Invalid after 180 seconds, hold down 180, flushed after 240
Outgoing update filter list for all interfaces is not set
Incoming update filter list for all interfaces is not set
Redistributing: rip
Default version control: send version 2, receive 2
Interface Send Recv Triggered RIP Key-chain
FastEthernet0/0 2 2
FastEthernet0/1 2 2
Serial0/0/0 2 2
Automatic network summarization is in effect
Maximum path: 4
Routing for Networks:
10.0.0.0
192.168.30.0
192.168.40.0
Passive Interface(s):
Routing Information Sources:
Gateway Distance Last Update
10.1.4.1 120 00:00:20
Distance: (default is 120)
IOS 15.1
R3#
show ip protocols
Routing Protocol is "eigrp 10 "
Outgoing update filter list for all interfaces is not set
Incoming update filter list for all interfaces is not set
Default networks flagged in outgoing updates
Default networks accepted from incoming updates
Redistributing: eigrp 10
EIGRP-IPv4 Protocol for AS(10)
Metric weight K1=1, K2=0, K3=1, K4=0, K5=0
NSF-aware route hold timer is 240
Router-ID: 10.1.5.2
Topology : 0 (base)
Active Timer: 3 min
Distance: internal 90 external 170
Maximum path: 4
Maximum hopcount 100
Maximum metric variance 1
Automatic Summarization: disabled
Automatic address summarization:
Maximum path: 4
Routing for Networks:
10.0.0.0
172.16.0.0
Routing Information Sources:
Gateway Distance Last Update
10.1.5.1 90 0
Distance: internal 90 external 170
Routing Protocol is "rip"
Sending updates every 30 seconds, next due in 27 seconds
Invalid after 180 seconds, hold down 180, flushed after 240
Outgoing update filter list for all interfaces is not set
Incoming update filter list for all interfaces is not set
Redistributing: rip
Default version control: send version 2, receive 2
Interface Send Recv Triggered RIP Key-chain
Dot11Radio0/0/0 2 2
FastEthernet0/0 2 2
Automatic network summarization is not in effect
Maximum path: 4
Routing for Networks:
10.0.0.0
172.16.0.0
Passive Interface(s):
Routing Information Sources:
Gateway Distance Last Update
10.1.5.1 120 00:00:02
Distance: (default is 120)
I'm also noticing that we have inconsistent auto-summarization settings- I was having trouble with this earlier. The book discusses
getting rid of the 172.16.0.0 summarized route in the EIGRP settings. I was not able to get rid of it, I think because RIP is still on, and RIP forces auto-summary
Part of the challenge here is that the book is strictly dealing with IOS 12.4
I will now make sure to turn auto summary off for both RIP and EIGRP on each of the four routers.
OK the part I am forgetting is that we are running RIP V2 which does not force auto-summary but runs it optionally, and we must turn it off to avoid auto summarization.
Corp(config)#
router rip
Corp(config-router)#
no auto-summary
Corp(config-router)#
router eigrp 10
Corp(config-router)#
no auto-summary
R1(config)#
router rip
R1(config-router)#
no auto-summary
R1(config-router)#
router eigrp 10
R1(config-router)#
no auto-summary
R1(config)#
router rip
R1(config-router)#
no auto-summary
R1(config-router)#
router eigrp 10
R2(config-router)#
no auto-summary
R3(config)#
router rip
R3(config-router)#
no auto-summary
R3(config-router)#
router eigrp 10
R3(config-router)#
no auto-summary
and lets see how the output looks now. This time I'll do show ip protocols and
show ip route side by side for each router
IOS 15.1
Corp#
show ip protocols
Routing Protocol is "eigrp 10 "
Outgoing update filter list for all interfaces is not set
Incoming update filter list for all interfaces is not set
Default networks flagged in outgoing updates
Default networks accepted from incoming updates
Redistributing: eigrp 10
EIGRP-IPv4 Protocol for AS(10)
Metric weight K1=1, K2=0, K3=1, K4=0, K5=0
NSF-aware route hold timer is 240
Router-ID: 10.1.1.1
Topology : 0 (base)
Active Timer: 3 min
Distance: internal 90 external 170
Maximum path: 4
Maximum hopcount 100
Maximum metric variance 1
Automatic Summarization: disabled
Automatic address summarization:
Maximum path: 4
Routing for Networks:
10.0.0.0
Routing Information Sources:
Gateway Distance Last Update
10.1.5.2 90 0
10.1.3.2 90 6464
10.1.2.2 90 6795
10.1.4.2 90 7955
Distance: internal 90 external 170
Routing Protocol is "rip" doesnt necessarily mean RIPv1
Sending updates every 30 seconds, next due in 3 seconds
Invalid after 180 seconds, hold down 180, flushed after 240
Outgoing update filter list for all interfaces is not set
Incoming update filter list for all interfaces is not set
Redistributing: rip
Default version control: send version 2, receive 2 RIPv2 is specified
Interface Send Recv Triggered RIP Key-chain
Vlan1 2 2
FastEthernet0/0 2 2
Serial0/1/0 2 2
Serial0/0/1 2 2
Serial0/0/0 2 2
Automatic network summarization is not in effect
Maximum path: 4
Routing for Networks:
10.0.0.0
Passive Interface(s):
Routing Information Sources:
Gateway Distance Last Update
10.1.5.2 120 00:00:02
10.1.3.2 120 00:00:21
10.1.2.2 120 00:00:21
10.1.4.2 120 00:00:04
Distance: (default is 120)
IOS 15.1
Corp#
show ip route
Gateway of last resort is not set
10.0.0.0/8 is variably subnetted, 10 subnets, 2 masks
C 10.1.1.0/24 is directly connected, Vlan1
L 10.1.1.1/32 is directly connected, Vlan1
C 10.1.2.0/24 is directly connected, Serial0/0/0
L 10.1.2.1/32 is directly connected, Serial0/0/0
C 10.1.3.0/24 is directly connected, Serial0/0/1
L 10.1.3.1/32 is directly connected, Serial0/0/1
C 10.1.4.0/24 is directly connected, Serial0/1/0
L 10.1.4.1/32 is directly connected, Serial0/1/0
C 10.1.5.0/24 is directly connected, FastEthernet0/0
L 10.1.5.1/32 is directly connected, FastEthernet0/0
172.16.0.0/24 is subnetted, 1 subnets
D 172.16.10.0/24 [90/28160] via 10.1.5.2, 00:57:25, FastEthernet0/0
D 192.168.10.0/24 [90/2172416] via 10.1.3.2, 00:57:20, Serial0/0/1
[90/2172416] via 10.1.2.2, 00:57:20, Serial0/0/0
D 192.168.20.0/24 [90/2172416] via 10.1.3.2, 00:57:20, Serial0/0/1
[90/2172416] via 10.1.2.2, 00:57:20, Serial0/0/0
D 192.168.30.0/24 [90/2172416] via 10.1.4.2, 00:57:19, Serial0/1/0
D 192.168.40.0/24 [90/2172416] via 10.1.4.2, 00:57:19, Serial0/1/0
IOS 12.4
R1#
show ip protocols
Routing Protocol is "eigrp 10 "
Outgoing update filter list for all interfaces is not set
Incoming update filter list for all interfaces is not set
Default networks flagged in outgoing updates
Default networks accepted from incoming updates
EIGRP metric weight K1=1, K2=0, K3=1, K4=0, K5=0
EIGRP maximum hopcount 100
EIGRP maximum metric variance 1
Redistributing: eigrp 10
Automatic network summarization is not in effect
Maximum path: 4
Routing for Networks:
10.0.0.0
192.168.10.0
192.168.20.0
Routing Information Sources:
Gateway Distance Last Update
10.1.3.1 90 6465
10.1.2.1 90 6794
Distance: internal 90 external 170
Routing Protocol is "rip"
Sending updates every 30 seconds, next due in 26 seconds
Invalid after 180 seconds, hold down 180, flushed after 240
Outgoing update filter list for all interfaces is not set
Incoming update filter list for all interfaces is not set
Redistributing: rip
Default version control: send version 2, receive 2
Interface Send Recv Triggered RIP Key-chain
FastEthernet0/0 2 2
FastEthernet0/1 2 2
Serial0/0/0 2 2
Serial0/0/1 2 2
Automatic network summarization is not in effect
Maximum path: 4
Routing for Networks:
10.0.0.0
192.168.10.0
192.168.20.0
Passive Interface(s):
Routing Information Sources:
Gateway Distance Last Update
10.1.3.1 120 00:00:03
10.1.2.1 120 00:00:03
Distance: (default is 120)
IOS 12.4
R1#
show ip route
Gateway of last resort is not set
10.0.0.0/24 is subnetted, 5 subnets
D 10.1.1.0 [90/27769856] via 10.1.3.1, 00:54:47, Serial0/0/1
[90/27769856] via 10.1.2.1, 00:54:47, Serial0/0/0
C 10.1.2.0 is directly connected, Serial0/0/0
C 10.1.3.0 is directly connected, Serial0/0/1
D 10.1.4.0 [90/2681856] via 10.1.3.1, 00:54:47, Serial0/0/1
[90/2681856] via 10.1.2.1, 00:54:47, Serial0/0/0
D 10.1.5.0 [90/2172416] via 10.1.3.1, 00:54:47, Serial0/0/1
[90/2172416] via 10.1.2.1, 00:54:47, Serial0/0/0
172.16.0.0/24 is subnetted, 1 subnets
D 172.16.10.0 [90/2172416] via 10.1.3.1, 00:54:47, Serial0/0/1
[90/2172416] via 10.1.2.1, 00:54:47, Serial0/0/0
C 192.168.10.0/24 is directly connected, FastEthernet0/0
C 192.168.20.0/24 is directly connected, FastEthernet0/1
D 192.168.30.0/24 [90/2684416] via 10.1.3.1, 00:54:46, Serial0/0/1
[90/2684416] via 10.1.2.1, 00:54:46, Serial0/0/0
D 192.168.40.0/24 [90/2684416] via 10.1.3.1, 00:54:46, Serial0/0/1
[90/2684416] via 10.1.2.1, 00:54:46, Serial0/0/0
note that the DUAL routes being advertised from the 10.0.0.0 networks are all specific to the third octet.. that's because we are reading those routes
from their source, aka the router which they are directly connected to, Corp.
and on Corp, those networks were added to the interfaces with a /24 mask.
so even though our EIGRP config doesnt specifically include /24 networks.. we told it to include anything with a 10.x.x.x
Corp is advertising to R1 our /24 network interfaces that have a 10 in the first octet, EXCEPT the two which are directly connected to R1
10.1.1.0
10.1.4.0
10.1.5.0
are assumed to be the subnets based on the info we configured, which was 10.1.4.1/24 on corp, and 10.1.4.2/24 on r2 s0/0/0
nowhere in this configuration, have we entered the 10.1.4.0 network.
EIGRP is figuring it out based on the /24 mask we gave when assiging he IPs to the interfaces
IOS 12.4
R2#
show ip protocols
Routing Protocol is "eigrp 10 "
Outgoing update filter list for all interfaces is not set
Incoming update filter list for all interfaces is not set
Default networks flagged in outgoing updates
Default networks accepted from incoming updates
EIGRP metric weight K1=1, K2=0, K3=1, K4=0, K5=0
EIGRP maximum hopcount 100
EIGRP maximum metric variance 1
Redistributing: eigrp 10
Automatic network summarization is not in effect
Maximum path: 4
Routing for Networks:
10.0.0.0
192.168.30.0
192.168.40.0
Routing Information Sources:
Gateway Distance Last Update
10.1.4.1 90 7955
Distance: internal 90 external 170
Routing Protocol is "rip"
Sending updates every 30 seconds, next due in 18 seconds
Invalid after 180 seconds, hold down 180, flushed after 240
Outgoing update filter list for all interfaces is not set
Incoming update filter list for all interfaces is not set
Redistributing: rip
Default version control: send version 2, receive 2
Interface Send Recv Triggered RIP Key-chain
FastEthernet0/0 2 2
FastEthernet0/1 2 2
Serial0/0/0 2 2
Automatic network summarization is not in effect
Maximum path: 4
Routing for Networks:
10.0.0.0
192.168.30.0
192.168.40.0
Passive Interface(s):
Routing Information Sources:
Gateway Distance Last Update
10.1.4.1 120 00:00:07
Distance: (default is 120)
IOS 12.4
R2#
show ip route
Gateway of last resort is not set
10.0.0.0/24 is subnetted, 5 subnets
D 10.1.1.0 [90/27769856] via 10.1.4.1, 00:59:10, Serial0/0/0
D 10.1.2.0 [90/2681856] via 10.1.4.1, 00:59:10, Serial0/0/0
D 10.1.3.0 [90/2681856] via 10.1.4.1, 00:59:10, Serial0/0/0
C 10.1.4.0 is directly connected, Serial0/0/0
D 10.1.5.0 [90/2172416] via 10.1.4.1, 00:59:10, Serial0/0/0
172.16.0.0/24 is subnetted, 1 subnets
D 172.16.10.0 [90/2172416] via 10.1.4.1, 00:59:10, Serial0/0/0
D 192.168.10.0/24 [90/2684416] via 10.1.4.1, 00:59:10, Serial0/0/0
D 192.168.20.0/24 [90/2684416] via 10.1.4.1, 00:59:10, Serial0/0/0
C 192.168.30.0/24 is directly connected, FastEthernet0/0
C 192.168.40.0/24 is directly connected, FastEthernet0/1
IOS 15.1
R3#
show ip protocols
Routing Protocol is "eigrp 10 "
Outgoing update filter list for all interfaces is not set
Incoming update filter list for all interfaces is not set
Default networks flagged in outgoing updates
Default networks accepted from incoming updates
Redistributing: eigrp 10
EIGRP-IPv4 Protocol for AS(10)
Metric weight K1=1, K2=0, K3=1, K4=0, K5=0
NSF-aware route hold timer is 240
Router-ID: 10.1.5.2
Topology : 0 (base)
Active Timer: 3 min
Distance: internal 90 external 170
Maximum path: 4
Maximum hopcount 100
Maximum metric variance 1
Automatic Summarization: disabled
Automatic address summarization:
Maximum path: 4
Routing for Networks:
10.0.0.0
172.16.0.0
Routing Information Sources:
Gateway Distance Last Update
10.1.5.1 90 0
Distance: internal 90 external 170
Routing Protocol is "rip"
Sending updates every 30 seconds, next due in 15 seconds
Invalid after 180 seconds, hold down 180, flushed after 240
Outgoing update filter list for all interfaces is not set
Incoming update filter list for all interfaces is not set
Redistributing: rip
Default version control: send version 2, receive 2
Interface Send Recv Triggered RIP Key-chain
Dot11Radio0/0/0 2 2
FastEthernet0/0 2 2
Automatic network summarization is not in effect
Maximum path: 4
Routing for Networks:
10.0.0.0
172.16.0.0
Passive Interface(s):
Routing Information Sources:
Gateway Distance Last Update
10.1.5.1 120 00:00:14
Distance: (default is 120)
IOS 15.1
R3#
show ip route
Gateway of last resort is 10.1.5.1 to network 0.0.0.0
10.0.0.0/8 is variably subnetted, 6 subnets, 2 masks
D 10.1.1.0/24 [90/25628160] via 10.1.5.1, 00:59:52, FastEthernet0/0
D 10.1.2.0/24 [90/2172416] via 10.1.5.1, 00:59:47, FastEthernet0/0
D 10.1.3.0/24 [90/2172416] via 10.1.5.1, 00:59:52, FastEthernet0/0
D 10.1.4.0/24 [90/2172416] via 10.1.5.1, 00:59:52, FastEthernet0/0
C 10.1.5.0/24 is directly connected, FastEthernet0/0
L 10.1.5.2/32 is directly connected, FastEthernet0/0
172.16.0.0/16 is variably subnetted, 2 subnets, 2 masks
C 172.16.10.0/24 is directly connected, Dot11Radio0/0/0
L 172.16.10.1/32 is directly connected, Dot11Radio0/0/0
D 192.168.10.0/24 [90/2174976] via 10.1.5.1, 00:59:47, FastEthernet0/0
D 192.168.20.0/24 [90/2174976] via 10.1.5.1, 00:59:47, FastEthernet0/0
D 192.168.30.0/24 [90/2174976] via 10.1.5.1, 00:59:46, FastEthernet0/0
D 192.168.40.0/24 [90/2174976] via 10.1.5.1, 00:59:46, FastEthernet0/0
S* 0.0.0.0/0 [1/0] via 10.1.5.1
Observations:
Since this is a 15.1 router, we always get a "L" local route when
we have a "C" connected route. In R3's case, the 172.16.10.0 network
is directly connected. The interface which connects it, 172.16.10.1,
counts as a "local" route. This is NOT the case on the 12.4 routers.
looking to the left, our protocol output tells us two key facts for both EIGRP and RIP:
Routing for networks:
10.0.0.0
172.16.0.0
R3 is responsible for *sending* data about these two networks to our other EIGRP routers...
"I'm R3 and I can connect you to networks on the R3
router or networks on the Corp router"
Notice how the 192 networks arent listed. R3 isnt connected to a 192 network directly, nor is it connected to a neighbor who is directly connected.
If I, as a client, am sending data to a 192 network from the 172 network, I will start
at R3. Since R3 is receiving routes for the 192 networks via Corp, I will be able to reach a 192 network via Corp.
My connection to corp will happen VIA a "10.0.0.0" route.
R3 is technically only routing for 172 and 10 networks. Beyond that, it could potentially connect to many other different networks. But in terms of the R3 routing table,
all it can offer is a path out to the 172 network or the 10 network
Routing information sources:
10.1.5.1
In this case I can see that R3 is receiving routing data from one interface only,
and that is it's link to Corp. Some of the data we are receiving from Corp actually originates
at other routers, but we cant see that here; the data comes to us from Corp, and that is all we know
EIGRP TERMINOLOGY
FEASIBLE DISTANCE (FD)
the best metric among all paths, including to the next hop neighbor. You will only see the route with the lowest FD appear in the routing table
The FD is calculated by adding the reported distance from the neighbor (AD) plus the metric to that neighbor
ADVERTISED DISTANCE (AD)
the metric of a remote network as reported by a neighbor, listed second in parenthesis in toplogy table
P 192.168.20.0/24, 2 successors, FD is 2172416
via 10.1.3.2 (2172416/28160), Serial0/0/1
feasible / advertised
Neighbor Table
each router keeps state information about adjacent neighbors.. When a new neighbor is learned, the address and interface are recorded.
The neighbor table is stored in RAM.
Sequence numbres are used to match acks with update packets. The last squence number received from a neighbor is recorded so out of order packets
can be detected
Topology Table
acted upon by DUAL Diffusing Update Alogorithm. Contains all destinations advertised by neighboring routers.
For each neighbor, the adversited distance, which comes only from that neighbor's routing table, is recorded
The feasible distance is also recorded.
Feasible Successor
a PATH whose advertised distance is less than the feasible distance of the current succesor, and is considered a backup route.
EIGRP keeps up to 16 feasible successors in the toplogy table.
The one with the best metric (The Successor) is copied and placed into the routing table
Successor
the best route to a remote network, used by EIGRP to forward traffic. It's backed up by a feasible successor, if one is available.
lets demo some more of the commands
VERIFYING EIGRP
several commands available to verify and troubleshoot
show ip route
show the entire routing table
show ip route eigrp
show only EIGRP entries in the routing table
show ip eigrp neighbors
show all EIGRP neigbors
show ip eigrp topology
show entries in the EIGRP topology table
show ip protocols
shows routing protocols configuration
debug eigrp packet
shows hello packets sent/received between adjacent routers
debug ip eigrp events
shows EIGRP changes and updates as they occur on your network
Corp#
show ip eigrp ?
interfaces IP-EIGRP interfaces
neighbors IP-EIGRP neighbors
topology IP-EIGRP Topology Table
traffic IP-EIGRP Traffic Statistics
Corp#
show ip eigrp topology
IP-EIGRP Topology Table for AS 10/ID(10.1.5.1)
Codes: P - Passive, A - Active, U - Update, Q - Query, R - Reply,
r - Reply status
P 10.1.1.0/24, 1 successors, FD is 25625600
via Connected, Vlan1
P 10.1.2.0/24, 1 successors, FD is 2169856
via Connected, Serial0/0/0
P 10.1.3.0/24, 1 successors, FD is 2169856
via Connected, Serial0/0/1
P 10.1.4.0/24, 1 successors, FD is 2169856
via Connected, Serial0/1/0
P 10.1.5.0/24, 1 successors, FD is 28160
via Connected, FastEthernet0/0
P 172.16.10.0/24, 1 successors, FD is 28160
via 10.1.5.2 (28160/25600), FastEthernet0/0
P 192.168.10.0/24, 2 successors, FD is 2172416
via 10.1.3.2 (2172416/28160), Serial0/0/1
via 10.1.2.2 (2172416/28160), Serial0/0/0
P 192.168.20.0/24, 2 successors, FD is 2172416
via 10.1.3.2 (2172416/28160), Serial0/0/1
via 10.1.2.2 (2172416/28160), Serial0/0/0
P 192.168.30.0/24, 1 successors, FD is 2172416
via 10.1.4.2 (2172416/28160), Serial0/1/0
P 192.168.40.0/24, 1 successors, FD is 2172416
via 10.1.4.2 (2172416/28160), Serial0/1/0
the "P" preceding each entry is for PASSIVE
these routes are in a passive state, which is good
if they move to an ACTIVE state, it means the have lost their path in the network and looking for a replacement.
Each entry also shows the FEASIBLE DISTANCE, the next hop address, and the local egress interface
Corp#
show ip eigrp neighbors
IP-EIGRP neighbors for process 10
H Address Interface Hold Uptime SRTT RTO Q Seq
(sec) (ms) Cnt Num
0 10.1.5.2 Fa0/0 14 02:00:05 40 1000 0 19
1 10.1.3.2 Se0/0/1 13 01:59:59 40 1000 0 14
2 10.1.2.2 Se0/0/0 13 01:59:59 40 1000 0 13
3 10.1.4.2 Se0/1/0 12 01:59:57 40 1000 0 15
fields:
H - the order in which the neighbors were discovered
hold - how long the router will wait for a hello packet
uptime - how long the neigborship has been established
SRTT - smooth round trip timer - the time it takes for a round trip from this router, to neighbor, and back.
SRTT is used to determine how long to wait for a MULTICAST reply.
if a reply isnt received in time, the router switches to UNICASTS
RTO - Retransmission Time Out- is the time EIGRP waits before retransmitting a packet from the retransmission queue
Q - indicates wheter there are oustanding messages in the queue
Seq - indicates the sequence number of the last update from that neighbor. This is used to maintain syncrhonization and avoid duplicate
or out-of-sequence processing of messages
Corp#
show ip route eigrp
172.16.0.0/24 is subnetted, 1 subnets
D 172.16.10.0 [90/28160] via 10.1.5.2, 02:08:04, FastEthernet0/0
D 192.168.10.0/24 [90/2172416] via 10.1.3.2, 02:07:59, Serial0/0/1
[90/2172416] via 10.1.2.2, 02:07:59, Serial0/0/0
D 192.168.20.0/24 [90/2172416] via 10.1.3.2, 02:07:59, Serial0/0/1
[90/2172416] via 10.1.2.2, 02:07:59, Serial0/0/0
D 192.168.30.0/24 [90/2172416] via 10.1.4.2, 02:07:58, Serial0/1/0
D 192.168.40.0/24 [90/2172416] via 10.1.4.2, 02:07:58, Serial0/1/0
Corp#
show ip eigrp interfaces
IP-EIGRP interfaces for process 10
Xmit Queue Mean Pacing Time Multicast Pending
Interface Peers Un/Reliable SRTT Un/Reliable Flow Timer Routes
Vlan 0 0/0 1236 0/10 0 0
Fa0/0 1 0/0 1236 0/10 0 0
Se0/1/0 1 0/0 1236 0/10 0 0
Se0/0/1 1 0/0 1236 0/10 0 0
Se0/0/0 1 0/0 1236 0/10 0 0
Corp#
show ip protocols
Routing Protocol is "eigrp 10 "
Outgoing update filter list for all interfaces is not set
Incoming update filter list for all interfaces is not set
Default networks flagged in outgoing updates
Default networks accepted from incoming updates
Redistributing: eigrp 10
EIGRP-IPv4 Protocol for AS(10)
Metric weight K1=1, K2=0, K3=1, K4=0, K5=0 using K1 bandwidth and K2 delay by default
NSF-aware route hold timer is 240
Router-ID: 10.1.1.1
Topology : 0 (base)
Active Timer: 3 min
Distance: internal 90 external 170
Maximum path: 4
Maximum hopcount 100
Maximum metric variance 1
Automatic Summarization: disabled
Automatic address summarization:
Maximum path: 4
Routing for Networks:
10.0.0.0
Routing Information Sources:
Gateway Distance Last Update
10.1.5.2 90 0
10.1.3.2 90 8936
10.1.4.2 90 9511
10.1.2.2 90 9597
Distance: internal 90 external 170
Routing Protocol is "rip"
Sending updates every 30 seconds, next due in 13 seconds
Invalid after 180 seconds, hold down 180, flushed after 240
Outgoing update filter list for all interfaces is not set
Incoming update filter list for all interfaces is not set
Redistributing: rip
Default version control: send version 2, receive 2
Interface Send Recv Triggered RIP Key-chain
Vlan1 2 2
FastEthernet0/0 2 2
Serial0/0/1 2 2
Serial0/1/0 2 2
Serial0/0/0 2 2
Automatic network summarization is not in effect
Maximum path: 4
Routing for Networks:
10.0.0.0
Passive Interface(s):
Routing Information Sources:
Gateway Distance Last Update
10.1.5.2 120 00:00:05
10.1.3.2 120 00:00:12
10.1.2.2 120 00:00:12
10.1.4.2 120 00:00:17
Distance: (default is 120)
corp#
debug eigrp packet
break into two columns for readability
Observations:
There doesnt appear to be a pattern in the order each router is addressed, except that the TO's and FROM"s are grouped together
The TO messages dont show the destination IP, only the egress local interface
The FROM messages do show the remote IP, as well as the local ingress interface
Corp#
EIGRP: Received HELLO on FastEthernet0/0 nbr 10.1.5.2
AS 10, Flags 0x0, Seq 18/0 idbQ 0/0
hello from R3
Corp#
EIGRP: Received HELLO on Serial0/1/0 nbr 10.1.4.2
AS 10, Flags 0x0, Seq 16/0 idbQ 0/0
hello from R2
Corp#
EIGRP: Received HELLO on Serial0/0/0 nbr 10.1.2.2
AS 10, Flags 0x0, Seq 19/0 idbQ 0/0
hello from R1
------------------------------------------------------------
Corp#
EIGRP: Sending HELLO on Serial0/1/0
AS 10, Flags 0x0, Seq 21/0 idbQ 0/0 iidbQ un/rely 0/0
hello to R2
Corp#
EIGRP: Sending HELLO on FastEthernet0/0
AS 10, Flags 0x0, Seq 21/0 idbQ 0/0 iidbQ un/rely 0/0
hello to R3
Corp#
EIGRP: Sending HELLO on Serial0/0/1
AS 10, Flags 0x0, Seq 21/0 idbQ 0/0 iidbQ un/rely 0/0
hello to R1
Corp#
EIGRP: Sending HELLO on Serial0/0/0
AS 10, Flags 0x0, Seq 21/0 idbQ 0/0 iidbQ un/rely 0/0
hello to R1
Corp#
EIGRP: Sending HELLO on Vlan1
AS 10, Flags 0x0, Seq 21/0 idbQ 0/0 iidbQ un/rely 0/0
hello to switch card (not a router....)
------------------------------------------------------------
Corp#
EIGRP: Received HELLO on Serial0/0/1 nbr 10.1.3.2
AS 10, Flags 0x0, Seq 19/0 idbQ 0/0
hello from R1
Corp#
EIGRP: Received HELLO on FastEthernet0/0 nbr 10.1.5.2
AS 10, Flags 0x0, Seq 18/0 idbQ 0/0
hello from R3
Corp#
EIGRP: Received HELLO on Serial0/0/0 nbr 10.1.2.2
AS 10, Flags 0x0, Seq 19/0 idbQ 0/0
hello from R1
Corp#
EIGRP: Received HELLO on Serial0/1/0 nbr 10.1.4.2
AS 10, Flags 0x0, Seq 16/0 idbQ 0/0
hello from R2
------------------------------------------------------------
Corp#
EIGRP: Sending HELLO on Serial0/1/0
AS 10, Flags 0x0, Seq 21/0 idbQ 0/0 iidbQ un/rely 0/0
hello to R2... no neighbor IP?
Corp#
EIGRP: Sending HELLO on Serial0/0/0
AS 10, Flags 0x0, Seq 21/0 idbQ 0/0 iidbQ un/rely 0/0
hello to R1... no neighbor IP?
Corp#
EIGRP: Sending HELLO on FastEthernet0/0
AS 10, Flags 0x0, Seq 21/0 idbQ 0/0 iidbQ un/rely 0/0
hello to R3... no neighbor IP?
Corp#
EIGRP: Sending HELLO on Serial0/0/1
AS 10, Flags 0x0, Seq 21/0 idbQ 0/0 iidbQ un/rely 0/0
hello to R1
Corp#
EIGRP: Sending HELLO on Vlan1
AS 10, Flags 0x0, Seq 21/0 idbQ 0/0 iidbQ un/rely 0/0
hello to switch card (not a router)
------------------------------------------------------------
OUTPUT CONTINUES IN NEXT COLUMN
Corp#
EIGRP: Received HELLO on Serial0/0/1 nbr 10.1.3.2
AS 10, Flags 0x0, Seq 19/0 idbQ 0/0
hello from R1
Corp#
EIGRP: Received HELLO on FastEthernet0/0 nbr 10.1.5.2
AS 10, Flags 0x0, Seq 18/0 idbQ 0/0
hello from R3
Corp#
EIGRP: Received HELLO on Serial0/0/0 nbr 10.1.2.2
AS 10, Flags 0x0, Seq 19/0 idbQ 0/0
hello from R1
Corp#
EIGRP: Received HELLO on Serial0/1/0 nbr 10.1.4.2
AS 10, Flags 0x0, Seq 16/0 idbQ 0/0
hello from R2
------------------------------------------------------------
Corp#
EIGRP: Sending HELLO on Serial0/1/0
AS 10, Flags 0x0, Seq 21/0 idbQ 0/0 iidbQ un/rely 0/0
hello to R2
Corp#
EIGRP: Sending HELLO on Serial0/0/0
AS 10, Flags 0x0, Seq 21/0 idbQ 0/0 iidbQ un/rely 0/0
hello to R1
Corp#
EIGRP: Sending HELLO on Vlan1
AS 10, Flags 0x0, Seq 21/0 idbQ 0/0 iidbQ un/rely 0/0
hello to Corp switchcard
Corp#
EIGRP: Sending HELLO on Serial0/0/1
AS 10, Flags 0x0, Seq 21/0 idbQ 0/0 iidbQ un/rely 0/0
hello to R1
Corp#
EIGRP: Sending HELLO on FastEthernet0/0
AS 10, Flags 0x0, Seq 21/0 idbQ 0/0 iidbQ un/rely 0/0
hello to R3... no neighbor IP?
------------------------------------------------------------
Corp#
EIGRP: Received HELLO on Serial0/0/1 nbr 10.1.3.2
AS 10, Flags 0x0, Seq 19/0 idbQ 0/0
hello from R1
Corp#
EIGRP: Received HELLO on FastEthernet0/0 nbr 10.1.5.2
AS 10, Flags 0x0, Seq 18/0 idbQ 0/0
hello from R3
Corp#
EIGRP: Received HELLO on Serial0/1/0 nbr 10.1.4.2
AS 10, Flags 0x0, Seq 16/0 idbQ 0/0
hello from R2
Corp#
EIGRP: Received HELLO on Serial0/0/0 nbr 10.1.2.2
AS 10, Flags 0x0, Seq 19/0 idbQ 0/0
hello from R1
------------------------------------------------------------
Corp#
EIGRP: Sending HELLO on Serial0/1/0
AS 10, Flags 0x0, Seq 21/0 idbQ 0/0 iidbQ un/rely 0/0
hello to R2
Corp#
EIGRP: Sending HELLO on Vlan1
AS 10, Flags 0x0, Seq 21/0 idbQ 0/0 iidbQ un/rely 0/0
hello to Corp switchcard
EIGRP: Sending HELLO on Serial0/0/0
AS 10, Flags 0x0, Seq 21/0 idbQ 0/0 iidbQ un/rely 0/0
hello to R1
EIGRP: Sending HELLO on Serial0/0/1
AS 10, Flags 0x0, Seq 21/0 idbQ 0/0 iidbQ un/rely 0/0
hello to R1
Corp#
EIGRP: Sending HELLO on FastEthernet0/0
AS 10, Flags 0x0, Seq 21/0 idbQ 0/0 iidbQ un/rely 0/0
hello to R3
------------------------------------------------------------
Now some videos. To reinforce EIGRP concepts, and lead into OSPF
OSPF - OPEN SHORTEST PATH FIRST
Before enabling OSPF, we'll turn off RIP and EIGRP on all four routers.
Device(config)#
no router eigrp 10
Device(config)#
no router rip
The OSPF configs for the local egress ip address
Corp(config)#
router ospf 132
Corp(config)#
network 10.1.0.0 0.0.255.255 area 0
R1(config)#
router ospf 1
R1(config)#
network 10.1.0.0 0.0.255.255 area 0
R1(config)#
network 192.168.0.0 0.0.255.255 area 0
R2(config)#
router ospf 45678
R2(config)#
network 10.0.0.0 0.0.0.255 area 0
R2(config)#
network 192.168.30.1 0.0.0.0 area 0
R2(config)#
network 192.168.40.1 0.0.0.0 area 0
all 32 bits of the mask are specified for the 192 entries;
these are not network id's, they are HOST id's of the specific interfaces, which are EGRESS interfaces on the router we are configuring
R3(config)#
router ospf 1
R2(config)#
network 10.1.5.2 0.0.0.255 area 0
R2(config)#
network 172.16.10.0 0.0.0.255 area 0
Wildcard Masks
these notes are not intended to be a precise explanation of wlidcard masking, but rather a look into my thought process as I am learning the concept.
resources:
traceroute blog examples
routerjockey blog examples
subnetonline wildcard calculator
Ch 9 Exam Essentials
1. Know EIGRP features
classless (like RipV2 and OSPF)
distance vector
supports IP, IPX, appleTalk, IPV6
supports summaries and discontiguous networks
uses the Diffusing Update Algorithm (DUAL) to maintain route information
uses RTP to communicate with other EIGRP routers
uses the concept of an autonomous system to describe the set of contiguous routers that run the same routing protocol and share routing information
considered CLASSLESS- includes the subnet mask in its route updates
sends traditional distance-vector updates containing info about networks plus the cost of reaching them from the perspective of the advertising router
but not strictly distance-vector. Has link-state characteristics: synchronizes routing tables between neighbors at startup and then sends specific updates only when topology changes.
max hop count of 255 (default is 100)
but hop count is NOT a metric, like in RIP. Hop count is how many routers an EIGRP route update can traverse before being discarded. This limits the size of the AS.
2. Know how to configure EIGRP
the router eigrp [as] command turns EIGRP routing on in the router. Unlike RIPv1, EIGRP uses classless routing. BUT you can still configure as classful.
R1(config)#
router eigrp 10
enters router config mode
R1(config-router)#
network 10.0.0.0
on this router, interfaces that fall within 10.0.0.0 will advertise EIGRP info
3. Know how to verify EIGRP operation
Corp#
show ip
protocols
Corp#
show ip
route
Corp#
show ip
route eigrp
Corp#
show ip
eigrp neighbors
Corp#
show ip
eigrp topology
Corp#
show ip
eigrp interfaces
Corp#
show ip
protocols
info about all active routing protocols
Routing Protocol is "eigrp 10 "
Outgoing update filter list for all interfaces is not set
Incoming update filter list for all interfaces is not set
Default networks flagged in outgoing updates
Default networks accepted from incoming updates
Redistributing: eigrp 10
EIGRP-IPv4 Protocol for AS(10)
Metric weight K1=1, K2=0, K3=1, K4=0, K5=0
NSF-aware route hold timer is 240
Router-ID: 10.1.1.1
Topology : 0 (base)
Active Timer: 3 min
Distance: internal 90 external 170
Maximum path: 4
Maximum hopcount 100
Maximum metric variance 1
Automatic Summarization: disabled
Automatic address summarization:
Maximum path: 4
Routing for Networks:
10.0.0.0
Routing Information Sources:
Gateway Distance Last Update
10.1.2.2 90 200105
10.1.3.2 90 200113
10.1.4.2 90 254351
10.1.5.2 90 303742
Distance: internal 90 external 170
Corp#
show ip
protocols
(continued)
Routing Protocol is "rip"
Sending updates every 30 seconds, next due in 6 seconds
Invalid after 180 seconds, hold down 180, flushed after 240
Outgoing update filter list for all interfaces is not set
Incoming update filter list for all interfaces is not set
Redistributing: rip
Default version control: send version 2, receive 2
Interface Send Recv Triggered RIP Key-chain
Vlan1 2 2
FastEthernet0/0 2 2
Serial0/1/0 2 2
Serial0/0/1 2 2
Serial0/0/0 2 2
Automatic network summarization is not in effect
Maximum path: 4
Routing for Networks:
10.0.0.0
Passive Interface(s):
Routing Information Sources:
Gateway Distance Last Update
10.1.5.2 120 00:00:15
10.1.3.2 120 00:00:01
10.1.2.2 120 00:00:01
10.1.4.2 120 00:00:17
Distance: (default is 120)
Corp#
show ip
route
entire routing table
Codes: L - local, C - connected, S - static, R - RIP, M - mobile, B - BGP
D - EIGRP, EX - EIGRP external, O - OSPF, IA - OSPF inter area
N1 - OSPF NSSA external type 1, N2 - OSPF NSSA external type 2
E1 - OSPF external type 1, E2 - OSPF external type 2, E - EGP
i - IS-IS, L1 - IS-IS level-1, L2 - IS-IS level-2, ia - IS-IS inter area
* - candidate default, U - per-user static route, o - ODR
P - periodic downloaded static route
Gateway of last resort is not set
10.0.0.0/8 is variably subnetted, 10 subnets, 2 masks
C 10.1.1.0/24 is directly connected, Vlan1
L 10.1.1.1/32 is directly connected, Vlan1
C 10.1.2.0/24 is directly connected, Serial0/0/0
L 10.1.2.1/32 is directly connected, Serial0/0/0
C 10.1.3.0/24 is directly connected, Serial0/0/1
L 10.1.3.1/32 is directly connected, Serial0/0/1
C 10.1.4.0/24 is directly connected, Serial0/1/0
L 10.1.4.1/32 is directly connected, Serial0/1/0
C 10.1.5.0/24 is directly connected, FastEthernet0/0
L 10.1.5.1/32 is directly connected, FastEthernet0/0
172.16.0.0/16 is variably subnetted, 2 subnets, 2 masks
R 172.16.0.0/16 [120/1] via 10.1.5.2, 00:00:14, FastEthernet0/0
D 172.16.10.0/24 [90/28160] via 10.1.5.2, 00:07:23, FastEthernet0/0
D 192.168.10.0/24 [90/2172416] via 10.1.3.2, 00:09:13, Serial0/0/1
[90/2172416] via 10.1.2.2, 00:09:13, Serial0/0/0
D 192.168.20.0/24 [90/2172416] via 10.1.3.2, 00:09:13, Serial0/0/1
[90/2172416] via 10.1.2.2, 00:09:13, Serial0/0/0
D 192.168.30.0/24 [90/2172416] via 10.1.4.2, 00:08:59, Serial0/1/0
D 192.168.40.0/24 [90/2172416] via 10.1.4.2, 00:08:59, Serial0/1/0
Shows the entire routing table
Corp#
show ip
eigrp toplogy
all nets the Corp router can see, including on the other side of other routers
IP-EIGRP Topology Table for AS 10/ID(10.1.5.1)
Codes: P - Passive, A - Active, U - Update, Q - Query, R - Reply,
r - Reply status
directly connected via local egress interface
P 10.1.1.0/24, 1 successors, FD is 25625600
via Connected, Vlan1
P 10.1.2.0/24, 1 successors, FD is 2169856
via Connected, Serial0/0/0
P 10.1.3.0/24, 1 successors, FD is 2169856
via Connected, Serial0/0/1
P 10.1.4.0/24, 1 successors, FD is 2169856
via Connected, Serial0/1/0
P 10.1.5.0/24, 1 successors, FD is 28160
via Connected, FastEthernet0/0
remotely connected via remote ingress ip address
P 172.16.10.0/24, 1 successors, FD is 28160
via 10.1.5.2 (28160/25600), FastEthernet0/0
P 192.168.10.0/24, 2 successors, FD is 2172416
via 10.1.3.2 (2172416/28160), Serial0/0/1
via 10.1.2.2 (2172416/28160), Serial0/0/0
P 192.168.20.0/24, 2 successors, FD is 2172416
via 10.1.3.2 (2172416/28160), Serial0/0/1
via 10.1.2.2 (2172416/28160), Serial0/0/0
P 192.168.30.0/24, 1 successors, FD is 2172416
via 10.1.4.2 (2172416/28160), Serial0/1/0
P 192.168.40.0/24, 1 successors, FD is 2172416
via 10.1.4.2 (2172416/28160), Serial0/1/0
Corp#
show ip
eigrp interfaces
local interfaces on Corp, with peer data, 5 total, including VLAN1 (0 peers, no router on this network)
IP-EIGRP interfaces for process 10
Xmit Queue Mean Pacing Time Multicast Pending
Interface Peers Un/Reliable SRTT Un/Reliable Flow Timer Routes
Vlan 0 0/0 1236 0/10 0 0
Fa0/0 1 0/0 1236 0/10 0 0
Se0/0/1 1 0/0 1236 0/10 0 0
Se0/1/0 1 0/0 1236 0/10 0 0
Se0/0/0 1 0/0 1236 0/10 0 0
Corp#
show ip
eigrp neighbors
remote interfaces on the 4 neighboring routers
IP-EIGRP neighbors for process 10
H Address Interface Hold Uptime SRTT RTO Q Seq
(sec) (ms) Cnt Num
0 10.1.2.2 Se0/0/0 14 00:54:33 40 1000 0 58
1 10.1.3.2 Se0/0/1 10 00:54:33 40 1000 0 57
2 10.1.4.2 Se0/1/0 14 00:53:38 40 1000 0 51
3 10.1.5.2 Fa0/0 11 00:52:49 40 1000 0 33
4. Compare OSPF and RIPv1
RIPv1 is distance-vector and supports only classful routing. No VLSM
OSPF is link-state and supports VLSM and classless routing
5. Know how OSPF routers become neighboars and/or adjacent
they become neighbors when they see eachother's hello packets.
area id must match, links must be on the same subnet, hello/dead timers must be the same.
OSPF only shares routes with neigbors who have also established adjacencies. NOT ALL NEIGHBORS become adjacent.
When an OSPF router first receives a hello packet, it verifies that the data in some fields matches its own locally configured information.
Should any of the checked data be different, the hello packet is discarded and not processed. The data fields verified are the Area ID,
Authentication, Network Mask (on broadcast networks), Hello Interval, Router Dead Interval, and Options fields. If this information doesn’t match,
then neighborship is stuck in the down stage.
packetpushers.net
6. Be able to configure single-area OSPF
two commands:
router ospf [process id]
network x.x.x.x y.y.y.y area z
7. Be able to verify the operation of OSPF
Corp#
show ip
protocols
Corp#
show ip
route
Corp#
show ip
ospf
Corp#
show ip
ospf database
Corp#
show ip
ospf interface
Corp#
show ip
ospf neighbor
IOS 15.1
Corp#
show ip
protocols
Routing Protocol is "ospf 132"
Outgoing update filter list for all interfaces is not set
Incoming update filter list for all interfaces is not set
Router ID 10.1.5.1
Number of areas in this router is 1. 1 normal 0 stub 0 nssa
Maximum path: 4
Routing for Networks:
10.1.0.0 0.0.255.255 area 0
Routing Information Sources:
Gateway Distance Last Update
10.1.5.1 110 00:08:51
172.16.10.1 110 00:08:51
192.168.20.1 110 00:12:53
192.168.40.1 110 00:09:35
Distance: (default is 110)
IOS 15.1
Corp#
show ip
route
10.0.0.0/8 is variably subnetted, 10 subnets, 2 masks
C 10.1.1.0/24 is directly connected, Vlan1
L 10.1.1.1/32 is directly connected, Vlan1
C 10.1.2.0/24 is directly connected, Serial0/0/0
L 10.1.2.1/32 is directly connected, Serial0/0/0
C 10.1.3.0/24 is directly connected, Serial0/0/1
L 10.1.3.1/32 is directly connected, Serial0/0/1
C 10.1.4.0/24 is directly connected, Serial0/1/0
L 10.1.4.1/32 is directly connected, Serial0/1/0
C 10.1.5.0/24 is directly connected, FastEthernet0/0
L 10.1.5.1/32 is directly connected, FastEthernet0/0
172.16.0.0/24 is subnetted, 1 subnets
O 172.16.10.0/24 [110/10] via 10.1.5.2, 00:09:09, FastEthernet0/0
O 192.168.10.0/24 [110/65] via 10.1.2.2, 00:13:11, Serial0/0/0
O 192.168.20.0/24 [110/65] via 10.1.2.2, 00:13:01, Serial0/0/0
O 192.168.30.0/24 [110/65] via 10.1.4.2, 00:09:54, Serial0/1/0
O 192.168.40.0/24 [110/65] via 10.1.4.2, 00:09:54, Serial0/1/0
IOS 15.1
Corp#
show ip
ospf
Routing Process "ospf 132" with ID 10.1.5.1
Supports only single TOS(TOS0) routes
Supports opaque LSA
SPF schedule delay 5 secs, Hold time between two SPFs 10 secs
Minimum LSA interval 5 secs. Minimum LSA arrival 1 secs
Number of external LSA 0. Checksum Sum 0x000000
Number of opaque AS LSA 0. Checksum Sum 0x000000
Number of DCbitless external and opaque AS LSA 0
Number of DoNotAge external and opaque AS LSA 0
Number of areas in this router is 1. 1 normal 0 stub 0 nssa
External flood list length 0
Area BACKBONE(0)
Number of interfaces in this area is 5
Area has no authentication
SPF algorithm executed 7 times
Area ranges are
Number of LSA 5. Checksum Sum 0x034486
Number of opaque link LSA 0. Checksum Sum 0x000000
Number of DCbitless LSA 0
Number of indication LSA 0
Number of DoNotAge LSA 0
Flood list length 0
IOS 15.1
Corp#
show ip
ospf database
OSPF Router with ID (10.1.5.1) (Process ID 132)
Router Link States (Area 0)
Link ID ADV Router Age Seq# Checksum Link count
192.168.20.1 192.168.20.1 854 0x80000006 0x00ae08 6
192.168.40.1 192.168.40.1 656 0x80000004 0x006bc6 4
10.1.5.1 10.1.5.1 612 0x8000000f 0x00ab77 8
172.16.10.1 172.16.10.1 612 0x80000003 0x00b30d 2
Net Link States (Area 0)
Link ID ADV Router Age Seq# Checksum
10.1.5.1 10.1.5.1 612 0x80000001 0x00cc34
ADV Router aka RID/Router ID, the highest IP address on the router
we are seeing three connected routers + our own router (Corp at 10.1.5.1)
IOS 15.1
Corp#
show ip
ospf interface
Vlan1 is up, line protocol is up
Internet address is 10.1.1.1/24, Area 0
Process ID 132, Router ID 10.1.5.1, Network Type BROADCAST, Cost: 1
Transmit Delay is 1 sec, State DR, Priority 1
Designated Router (ID) 10.1.5.1, Interface address 10.1.1.1
No backup designated router on this network
Timer intervals configured, Hello 10, Dead 40, Wait 40, Retransmit 5
Hello due in 00:00:08
Index 1/1, flood queue length 0
Next 0x0(0)/0x0(0)
Last flood scan length is 1, maximum is 1
Last flood scan time is 0 msec, maximum is 0 msec
Neighbor Count is 0, Adjacent neighbor count is 0
Suppress hello for 0 neighbor(s)
FastEthernet0/0 is up, line protocol is up
Internet address is 10.1.5.1/24, Area 0
Process ID 132, Router ID 10.1.5.1, Network Type BROADCAST, Cost: 1
Transmit Delay is 1 sec, State DR, Priority 1
Designated Router (ID) 10.1.5.1, Interface address 10.1.5.1
Backup Designated Router (ID) 172.16.10.1, Interface address 10.1.5.2
Timer intervals configured, Hello 10, Dead 40, Wait 40, Retransmit 5
Hello due in 00:00:07
Index 2/2, flood queue length 0
Next 0x0(0)/0x0(0)
Last flood scan length is 1, maximum is 1
Last flood scan time is 0 msec, maximum is 0 msec
Neighbor Count is 1, Adjacent neighbor count is 1
Adjacent with neighbor 172.16.10.1 (Backup Designated Router)
Suppress hello for 0 neighbor(s)
Serial0/0/1 is up, line protocol is up
Internet address is 10.1.3.1/24, Area 0
Process ID 132, Router ID 10.1.5.1, Network Type POINT-TO-POINT, Cost: 64
Transmit Delay is 1 sec, State POINT-TO-POINT,
Timer intervals configured, Hello 10, Dead 40, Wait 40, Retransmit 5
Hello due in 00:00:07
Index 3/3, flood queue length 0
Next 0x0(0)/0x0(0)
Last flood scan length is 1, maximum is 1
Last flood scan time is 0 msec, maximum is 0 msec
Neighbor Count is 1 , Adjacent neighbor count is 1
Adjacent with neighbor 192.168.20.1
Suppress hello for 0 neighbor(s)
Serial0/1/0 is up, line protocol is up
Internet address is 10.1.4.1/24, Area 0
Process ID 132, Router ID 10.1.5.1, Network Type POINT-TO-POINT, Cost: 64
Transmit Delay is 1 sec, State POINT-TO-POINT,
Timer intervals configured, Hello 10, Dead 40, Wait 40, Retransmit 5
Hello due in 00:00:07
Index 4/4, flood queue length 0
Next 0x0(0)/0x0(0)
Last flood scan length is 1, maximum is 1
Last flood scan time is 0 msec, maximum is 0 msec
Neighbor Count is 1 , Adjacent neighbor count is 1
Adjacent with neighbor 192.168.40.1
Suppress hello for 0 neighbor(s)
Serial0/0/0 is up, line protocol is up
Internet address is 10.1.2.1/24, Area 0
Process ID 132, Router ID 10.1.5.1, Network Type POINT-TO-POINT, Cost: 64
Transmit Delay is 1 sec, State POINT-TO-POINT,
Timer intervals configured, Hello 10, Dead 40, Wait 40, Retransmit 5
Hello due in 00:00:07
Index 5/5, flood queue length 0
Next 0x0(0)/0x0(0)
Last flood scan length is 1, maximum is 1
Last flood scan time is 0 msec, maximum is 0 msec
Neighbor Count is 1 , Adjacent neighbor count is 1
Adjacent with neighbor 192.168.20.1
Suppress hello for 0 neighbor(s)
IOS 15.1
Corp#
show ip
ospf neighbor
Neighbor ID Pri State Dead Time Address Interface
192.168.20.1 0 FULL/ - 00:00:31 10.1.3.2 Serial0/0/1
192.168.40.1 0 FULL/ - 00:00:33 10.1.4.2 Serial0/1/0
192.168.20.1 0 FULL/ - 00:00:31 10.1.2.2 Serial0/0/0
172.16.10.1 1 FULL/BDR 00:00:32 10.1.5.2 FastEthernet0/0
Flashcards
Chapter 9 Written Lab 9.0
1. What four routed protocols are supported by EIGRP?
IPX, IPv4, IPv6, AppleTalk
2. When is redistribution required for EIGRP?
when there are multiple autonomous systems
redistribution is required when more than one EIGRP session or process is running and they are identified with different ASNs.
redistribution shares toplogy information between EIGRP sessions
3. What command would be used to enable EIGRP with an autonmous system number of 300?
router eigrp 300
4. What command will tell EIGRP that it is connected to network 172.10.0.0?
network 172.10.0.0
5. What type of EIGRP interface will neither send nor receive Hello packets?
passive-interface s0/0
6. Write the command that will enable OSPF process 101 on a router
router ospf 101
7. Write the command that will display details of all OSFP routing processes enabled on a router
show ip ospf
8. Write the command that will display interface-specific OSPF information
show ip ospf interface
9. Write the command that will display all OSPF neighbors
show ip ospf neighbor
10. Write the command that will display all different OSPF route types that are currently known by the router
show ip route ospf
Chapter 9 Hands-On Labs
Build the network and configure interfaces
LabA(config)#
int f0/0
LabA(config-if)#
ip addr 172.16.10.1 255.255.255.0
LabA(config-if)#
no shut
LabB(config)#
int f0/0
LabB(config-if)#
ip addr 172.16.10.2 255.255.255.0
LabB(config-if)#
no shut
LabB(config-if)#
int s0/0/0
LabB(config-if)#
ip addr 172.16.20.1 255.255.255.0
LabB(config-if)#
no shut
LabC(config)#
int f0/0
LabC(config-if)#
ip addr 172.16.30.1 255.255.255.0
LabC(config-if)#
no shut
LabC(config-if)#
int s0/0/0
LabC(config-if)#
ip addr 172.16.20.2 255.255.255.0
LabC(config-if)#
no shut
LabC(config-if)#
int s0/0/1
LabC(config-if)#
ip addr 172.16.40.1 255.255.255.0
LabC(config-if)#
no shut
LabD(config)#
int s0/0/0
LabD(config-if)#
ip addr 172.16.40.2 255.255.255.0
LabD(config-if)#
no shut
LabD(config-if)#
int f0/0
LabD(config-if)#
ip addr 172.16.50.1 255.255.255.0
LabD(config-if)#
no shut
9.1 - Configure and Verfiy EIGRP
configure EIGRP on all 4 routers and observe results
LabA
LabA(config)#
router eigrp 100
LabA(config-router)#
net 172.16.0.0
[no output]
LabA#
show ip eigrp neighbors
IP-EIGRP neighbors for process 100
LabA#
show ip eigrp topology
IP-EIGRP Topology Table for AS 100/ID(172.16.10.1)
Codes: P - Passive, A - Active, U - Update, Q - Query, R - Reply,
r - Reply status
P 172.16.10.0/24, 1 successors, FD is 28160
via Connected, FastEthernet0/0
LabA#
show ip eigrp interfaces
IP-EIGRP interfaces for process 100
Xmit Queue Mean Pacing Time Multicast Pending
Interface Peers Un/Reliable SRTT Un/Reliable Flow Timer Routes
Fa0/0 0 0/0 1236 0/10 0 0
no neighbors at this point since EIGRP is only active on this router. One successor AKA route, which is the connection out of this router.
But note that we have no information about what's on the other side of that link
LabB
LabB(config)#
router eigrp 100
LabB(config-router)#
net 172.16.0.0
%DUAL-5-NBRCHANGE: IP-EIGRP 100:
Neighbor 172.16.10.1 (FastEthernet0/0) is up: new adjacency
LabB#
show ip eigrp neighbors
IP-EIGRP neighbors for process 100
H Address Interface Hold Uptime SRTT RTO Q Seq
(sec) (ms) Cnt Num
0 172.16.10.1 Fa0/0 12 00:00:14 40 1000 0 1
LabB#
show ip eigrp topology
IP-EIGRP Topology Table for AS 100/ID(172.16.20.1)
Codes: P - Passive, A - Active, U - Update, Q - Query, R - Reply,
r - Reply status
P 172.16.10.0/24, 1 successors, FD is 28160
via Connected, FastEthernet0/0
P 172.16.20.0/24, 1 successors, FD is 2169856
via Connected, Serial0/0/0
LabB#
show ip eigrp interfaces
IP-EIGRP interfaces for process 100
Xmit Queue Mean Pacing Time Multicast Pending
Interface Peers Un/Reliable SRTT Un/Reliable Flow Timer Routes
Fa0/0 1 0/0 1236 0/10 0 0
Se0/0/0 0 0/0 1236 0/10 0 0
We can see a neighbor at .1
We now have two paths out of this router. Left to neighbor. Exit at right is available as successor(route), but again we have no info about
what is on the other side, since that router has no EIGRP yet (s0/0/0 has no peers, but is an EIGRP interface)
LabC
LabC(config)#
router eigrp 100
LabC(config-router)#
net 172.16.0.0
%DUAL-5-NBRCHANGE: IP-EIGRP 100:
Neighbor 172.16.20.1 (Serial0/0/0) is up: new adjacency
LabC#
show ip eigrp neighbors
IP-EIGRP neighbors for process 100
H Address Interface Hold Uptime SRTT RTO Q Seq
(sec) (ms) Cnt Num
0 172.16.20.1 Se0/0/0 12 00:00:25 40 1000 0 8
LabC#
show ip eigrp toplogy
IP-EIGRP Topology Table for AS 100/ID(172.16.40.1)
Codes: P - Passive, A - Active, U - Update, Q - Query, R - Reply,
r - Reply status
P 172.16.10.0/24, 1 successors, FD is 2172416
via 172.16.20.1 (2172416/28160), Serial0/0/0
P 172.16.20.0/24, 1 successors, FD is 2169856
via Connected, Serial0/0/0
P 172.16.30.0/24, 1 successors, FD is 28160
via Connected, FastEthernet0/0
P 172.16.40.0/24, 1 successors, FD is 2169856
via Connected, Serial0/0/1
LabC#
show ip eigrp interfaces
IP-EIGRP interfaces for process 100
Xmit Queue Mean Pacing Time Multicast Pending
Interface Peers Un/Reliable SRTT Un/Reliable Flow Timer Routes
Fa0/0 0 0/0 1236 0/10 0 0
Se0/0/0 1 0/0 1236 0/10 0 0
Se0/0/1 0 0/0 1236 0/10 0 0
.1 router B interface is now a neighbor.
LabC topology shows the 3 direct connected networks AND the network on the other side of LabB since LabB is our EIGRP neighbor
3 eigrp interfaces:
Fa0/0 is ours at LabC- no peers bc there is no eigrp router on the other end
s0/0/0 is our interface out left to LabB which is an EIGRP peer
s0/0/1 is our interface out right which does not see an EIGRP peer but does put that net 172.16.40.0 in our topology
LabD
LabD(config)#
router eigrp 100
LabD(config-router)#
net 172.16.0.0
%DUAL-5-NBRCHANGE: IP-EIGRP 100:
Neighbor 172.16.40.1 (Serial0/0/0) is up: new adjacency
LabD#
show ip eigrp neighbors
IP-EIGRP neighbors for process 100
H Address Interface Hold Uptime SRTT RTO Q Seq
(sec) (ms) Cnt Num
0 172.16.40.1 Se0/0/0 11 00:00:14 40 1000 0 6
LabD#
show ip eigrp topology
IP-EIGRP Topology Table for AS 100/ID(172.16.50.1)
Codes: P - Passive, A - Active, U - Update, Q - Query, R - Reply,
r - Reply status
P 172.16.10.0/24, 1 successors, FD is 2684416
via 172.16.40.1 (2684416/2172416), Serial0/0/0
P 172.16.20.0/24, 1 successors, FD is 2681856
via 172.16.40.1 (2681856/2169856), Serial0/0/0
P 172.16.30.0/24, 1 successors, FD is 2172416
via 172.16.40.1 (2172416/28160), Serial0/0/0
P 172.16.40.0/24, 1 successors, FD is 2169856
via Connected, Serial0/0/0
P 172.16.50.0/24, 1 successors, FD is 28160
via Connected, FastEthernet0/0
LabD#
show ip eigrp interfaces
IP-EIGRP interfaces for process 100
Xmit Queue Mean Pacing Time Multicast Pending
Interface Peers Un/Reliable SRTT Un/Reliable Flow Timer Routes
Fa0/0 0 0/0 1236 0/10 0 0
Se0/0/0 1 0/0 1236 0/10 0 0
LabC to our left is now a neighbor at 172.16.40.1
toplogy shows a route out to the right (no router on that end)
a route to the left to LabC .40.0
the .10.0, .20.0, and .30.0 networks via info from LabC
2 eigrp interfaces-
fa0/0 out to the right
s0/0/0 out left to LabC
Time to remove EIGRP from all four routers to prepare for the OSPF lab next,
since EIGRP has a lower AD than OSPF
LabA(config)#
no router eigrp 100
LabB(config)#
no router eigrp 100
LabC(config)#
no router eigrp 100
LabD(config)#
no router eigrp 100
9.2 - Enabling the OSPF Process
9.3 - Configuring OSPF Interfaces
9.4 - Verifying OSPF Operation
LabA
LabA(config)#
router ospf 100
LabA(config-router)#
net 172.16.10.1 0.0.0.0 area 0
[no output]
LabA#
show ip ospf neighbor
[no output]
LabA#
show ip ospf database
OSPF Router with ID (172.16.10.1) (Process ID 100)
Router Link States (Area 0)
Link ID ADV Router Age Seq# Checksum Link count
172.16.10.1 172.16.10.1 44 0x80000001 0x00b24b 1
LabA#
show ip ospf interface
FastEthernet0/0 is up, line protocol is up
Internet address is 172.16.10.1/24, Area 0
Process ID 100, Router ID 172.16.10.1, Network Type BROADCAST, Cost: 1
Transmit Delay is 1 sec, State DR, Priority 1
Designated Router (ID) 172.16.10.1, Interface address 172.16.10.1
No backup designated router on this network
Timer intervals configured, Hello 10, Dead 40, Wait 40, Retransmit 5
Hello due in 00:00:08
Index 1/1, flood queue length 0
Next 0x0(0)/0x0(0)
Last flood scan length is 1, maximum is 1
Last flood scan time is 0 msec, maximum is 0 msec
Neighbor Count is 0, Adjacent neighbor count is 0
Suppress hello for 0 neighbor(s)
we're including this router's interface 172.16.10.1 in our ospf area 0
fa0/0 now registers as an ospf interface
the ospf database includes data about this link only.... LabA is counting itself(10.1) as ADVERTISTING router?
the designated router is .1 LabA
LabB
LabB(config)#
router ospf 101
LabB(config-router)#
net 172.16.10.2 0.0.0.0 area 0
LabB(config-router)#
net 172.16.20.1 0.0.0.0 area 0
01:26:36: %OSPF-5-ADJCHG: Process 101, Nbr 172.16.10.1
on FastEthernet0/0 from LOADING to FULL, Loading Done
LabB#
show ip ospf neighbor
Neighbor ID Pri State Dead Time Address Interface
172.16.10.1 1 FULL/DR 00:00:33 172.16.10.1
LabB#
show ip ospf database
OSPF Router with ID (172.16.20.1) (Process ID 101)
Router Link States (Area 0)
Link ID ADV Router Age Seq# Checksum Link count
172.16.10.1 172.16.10.1 145 0x80000002 0x0067cd 1
172.16.20.1 172.16.20.1 32 0x80000003 0x006e8f 2
Net Link States (Area 0)
Link ID ADV Router Age Seq# Checksum
172.16.10.1 172.16.10.1 145 0x80000001 0x00953d
LabB#
show ip ospf interface
FastEthernet0/0 is up, line protocol is up
Internet address is 172.16.10.2/24, Area 0
Process ID 101, Router ID 172.16.20.1, Network Type BROADCAST, Cost: 1
Transmit Delay is 1 sec, State BDR, Priority 1
Designated Router (ID) 172.16.10.1, Interface address 172.16.10.1
Backup Designated Router (ID) 172.16.20.1, Interface address 172.16.10.2
Timer intervals configured, Hello 10, Dead 40, Wait 40, Retransmit 5
Hello due in 00:00:03
Index 1/1, flood queue length 0
Next 0x0(0)/0x0(0)
Last flood scan length is 1, maximum is 1
Last flood scan time is 0 msec, maximum is 0 msec
Neighbor Count is 1, Adjacent neighbor count is 1
Adjacent with neighbor 172.16.10.1 (Designated Router)
Suppress hello for 0 neighbor(s)
Serial0/0/0 is up, line protocol is up
Internet address is 172.16.20.1/24, Area 0
Process ID 101, Router ID 172.16.20.1, Network Type POINT-TO-POINT, Cost: 64
Transmit Delay is 1 sec, State POINT-TO-POINT,
Timer intervals configured, Hello 10, Dead 40, Wait 40, Retransmit 5
Hello due in 00:00:04
Index 2/2, flood queue length 0
Next 0x0(0)/0x0(0)
Last flood scan length is 1, maximum is 1
Last flood scan time is 0 msec, maximum is 0 msec
Suppress hello for 0 neighbor(s)
We've include the two interfaces on this router in the OSPF area
and can now see Router A's interface 10.1 to the left as a neighbor in the area
the "OSPF Database" now shows two links 20.1(local) and 10.1(neighbor) as 'router link states'.
"ADV Router" means advertising router for the two links. The link address is used as the advertising router.
database shows "Net Link States" category with one entry- 172.16.10.1 which is the address of neighbor router to our left
we have two local OSPF interfaces- f0/0 and s0/0/0
LabC
LabC(config)#
router ospf 102
LabC(config-router)#
net 172.16.20.2 0.0.0.0 area 0
LabC(config-router)#
net 172.16.30.1 0.0.0.0 area 0
LabC(config-router)#
net 172.16.40.1 0.0.0.0 area 0
01:33:54: %OSPF-5-ADJCHG: Process 102, Nbr 172.16.20.1
on Serial0/0/0 from LOADING to FULL, Loading Done
LabC#
show ip ospf neighbor
Neighbor ID Pri State Dead Time Address Interface
172.16.20.1 0 FULL/ - 00:00:30 172.16.20.1 Serial0/0/0
LabC#
show ip ospf database
OSPF Router with ID (172.16.40.1) (Process ID 102)
Router Link States (Area 0)
Link ID ADV Router Age Seq# Checksum Link count
172.16.10.1 172.16.10.1 542 0x80000002 0x0067cd 1
172.16.20.1 172.16.20.1 90 0x80000004 0x00a551 3
172.16.40.1 172.16.40.1 37 0x80000004 0x00e47c 4
Net Link States (Area 0)
Link ID ADV Router Age Seq# Checksum
172.16.10.1 172.16.10.1 542 0x80000001 0x00953d
LabC#
show ip ospf interface
Serial0/0/0 is up, line protocol is up
Internet address is 172.16.20.2/24, Area 0
Process ID 102, Router ID 172.16.40.1, Network Type POINT-TO-POINT, Cost: 64
Transmit Delay is 1 sec, State POINT-TO-POINT,
Timer intervals configured, Hello 10, Dead 40, Wait 40, Retransmit 5
Hello due in 00:00:01
Index 1/1, flood queue length 0
Next 0x0(0)/0x0(0)
Last flood scan length is 1, maximum is 1
Last flood scan time is 0 msec, maximum is 0 msec
Neighbor Count is 1 , Adjacent neighbor count is 1
Adjacent with neighbor 172.16.20.1
Suppress hello for 0 neighbor(s)
FastEthernet0/0 is up, line protocol is up
Internet address is 172.16.30.1/24, Area 0
Process ID 102, Router ID 172.16.40.1, Network Type BROADCAST, Cost: 1
Transmit Delay is 1 sec, State DR, Priority 1
Designated Router (ID) 172.16.40.1, Interface address 172.16.30.1
No backup designated router on this network
Timer intervals configured, Hello 10, Dead 40, Wait 40, Retransmit 5
Hello due in 00:00:02
Index 2/2, flood queue length 0
Next 0x0(0)/0x0(0)
Last flood scan length is 1, maximum is 1
Last flood scan time is 0 msec, maximum is 0 msec
Neighbor Count is 0, Adjacent neighbor count is 0
Suppress hello for 0 neighbor(s)
Serial0/0/1 is up, line protocol is up
Internet address is 172.16.40.1/24, Area 0
Process ID 102, Router ID 172.16.40.1, Network Type POINT-TO-POINT, Cost: 64
Transmit Delay is 1 sec, State POINT-TO-POINT,
Timer intervals configured, Hello 10, Dead 40, Wait 40, Retransmit 5
Hello due in 00:00:08
Index 3/3, flood queue length 0
Next 0x0(0)/0x0(0)
Last flood scan length is 1, maximum is 1
Last flood scan time is 0 msec, maximum is 0 msec
Suppress hello for 0 neighbor(s)
we include the three nets conneted to labC in the area.. 20.0, 30.0, and 40.0
link to our left, 20.1 is visible as "Neighbor"
OSPF Database-
Router Link States are
10.1(Router A)
20.1(Router B)
40.1(Router C)(This router)
Net Link States
10.1(Router A)... why does only Router A show here?
Reference- router link state vs net link state
Router Link States are type 1 LSAs. It lists all the routers in the area and the number of interfaces. 40.1 has 4 interfaces
Net Link States are the multi-access networks (Type 2 LSAs). The ADV (advertising router) is the DR.
LabD
LabD(config)#
router ospf 103
LabD(config-router)#
net 172.16.40.2 0.0.0.0 area 0
LabD(config-router)#
net 172.16.50.1 0.0.0.0 area 0
01:37:11: %OSPF-5-ADJCHG: Process 103, Nbr 172.16.40.1
on Serial0/0/0 from LOADING to FULL, Loading Done
LabD#
show ip ospf neighbor
Neighbor ID Pri State Dead Time Address Interface
172.16.40.1 0 FULL/ - 00:00:32 172.16.40.1 Serial0/0/0
LabD#
show ip ospf database
OSPF Router with ID (172.16.50.1) (Process ID 103)
Router Link States (Area 0)
Link ID ADV Router Age Seq# Checksum Link count
172.16.10.1 172.16.10.1 785 0x80000002 0x0067cd 1
172.16.20.1 172.16.20.1 333 0x80000004 0x00a551 3
172.16.40.1 172.16.40.1 111 0x80000005 0x00013b 5
172.16.50.1 172.16.50.1 53 0x80000003 0x001023 3
Net Link States (Area 0)
Link ID ADV Router Age Seq# Checksum
172.16.10.1 172.16.10.1 785 0x80000001 0x00953d
LabD#
show ip ospf interface
Serial0/0/0 is up, line protocol is up
Internet address is 172.16.40.2/24, Area 0
Process ID 103, Router ID 172.16.50.1, Network Type POINT-TO-POINT, Cost: 64
Transmit Delay is 1 sec, State POINT-TO-POINT,
Timer intervals configured, Hello 10, Dead 40, Wait 40, Retransmit 5
Hello due in 00:00:01
Index 1/1, flood queue length 0
Next 0x0(0)/0x0(0)
Last flood scan length is 1, maximum is 1
Last flood scan time is 0 msec, maximum is 0 msec
Neighbor Count is 1 , Adjacent neighbor count is 1
Adjacent with neighbor 172.16.40.1
Suppress hello for 0 neighbor(s)
FastEthernet0/0 is up, line protocol is up
Internet address is 172.16.50.1/24, Area 0
Process ID 103, Router ID 172.16.50.1, Network Type BROADCAST, Cost: 1
Transmit Delay is 1 sec, State WAITING, Priority 1
No designated router on this network
No backup designated router on this network
Timer intervals configured, Hello 10, Dead 40, Wait 40, Retransmit 5
Hello due in 00:00:04
Index 2/2, flood queue length 0
Next 0x0(0)/0x0(0)
Last flood scan length is 1, maximum is 1
Last flood scan time is 0 msec, maximum is 0 msec
Neighbor Count is 0, Adjacent neighbor count is 0
Suppress hello for 0 neighbor(s)
observations
the OSPF databases now match across all 4 routers.
NOTE that this is a database of routers, identified by
router ID. It is not a topology that lists routers AND routes,
like in the "equivalent" eigrp command.show eigrp topology
----------------------------------------------------------------------------------
PAUSE- a tale of a misconfigured network
After a 9 month hiatus, I am reviewing this book and have made it back to Chapter 9. I'm studing this webpage, working thorough the OSPF configurations
described above, and I get stuck on the concept of "link count" under "Router Link States" found in the output of show ip ospf database
The structure of the notes above is helpful, because I was tracking the state of each router BEFORE i made changes to the subsquent router. But just to be sure,
today I decided to recreate the topology, then configure each router one at a time, noting the results as I went.
And I ran into some problems.
Here is the original topology:
And today's recreated toplogy:
After replicating the toplogy and programming the IP addresses on each router, I started on configurations, just like before:
LabA
LabA(config)#
router ospf 100
LabA(config-router)#
net 172.16.10.1 0.0.0.0 area 0
[no output]
LabA#
show ip ospf neighbor
[no output]
LabA#
show ip ospf database
OSPF Router with ID (172.16.10.1) (Process ID 100)
Router Link States (Area 0)
Link ID ADV Router Age Seq# Checksum Link count
172.16.10.1 172.16.10.1 44 0x80000001 0x00b24b 1
LabA#
show ip ospf interface
FastEthernet0/0 is up, line protocol is up
Internet address is 172.16.10.1/24, Area 0
Process ID 100, Router ID 172.16.10.1, Network Type BROADCAST, Cost: 1
Transmit Delay is 1 sec, State DR, Priority 1
Designated Router (ID) 172.16.10.1, Interface address 172.16.10.1
No backup designated router on this network
Timer intervals configured, Hello 10, Dead 40, Wait 40, Retransmit 5
Hello due in 00:00:08
Index 1/1, flood queue length 0
Next 0x0(0)/0x0(0)
Last flood scan length is 1, maximum is 1
Last flood scan time is 0 msec, maximum is 0 msec
Neighbor Count is 0, Adjacent neighbor count is 0
Suppress hello for 0 neighbor(s)
good so far.... On to LabB router
LabB
LabB(config)#
router ospf 101
LabB(config-router)#
net 172.16.10.2 0.0.0.0 area 0
LabB(config-router)#
net 172.16.20.1 0.0.0.0 area 0
01:26:36: %OSPF-5-ADJCHG: Process 101, Nbr 172.16.10.1
on FastEthernet0/0 from LOADING to FULL, Loading Done
LabB#
show ip ospf neighbor
Neighbor ID Pri State Dead Time Address Interface
172.16.10.1 1 FULL/DR 00:00:33 172.16.10.1
LabB#
show ip ospf database
OSPF Router with ID (172.16.20.1) (Process ID 101)
Router Link States (Area 0)
Link ID ADV Router Age Seq# Checksum Link count
172.16.10.1 172.16.10.1 145 0x80000002 0x0067cd 1
172.16.20.1 172.16.20.1 32 0x80000003 0x006e8f 2
Net Link States (Area 0)
Link ID ADV Router Age Seq# Checksum
172.16.10.1 172.16.10.1 145 0x80000001 0x00953d
LabB#
show ip ospf interface
FastEthernet0/0 is up, line protocol is up
Internet address is 172.16.10.2/24, Area 0
Process ID 101, Router ID 172.16.20.1, Network Type BROADCAST, Cost: 1
Transmit Delay is 1 sec, State BDR, Priority 1
Designated Router (ID) 172.16.10.1, Interface address 172.16.10.1
Backup Designated Router (ID) 172.16.20.1, Interface address 172.16.10.2
Timer intervals configured, Hello 10, Dead 40, Wait 40, Retransmit 5
Hello due in 00:00:03
Index 1/1, flood queue length 0
Next 0x0(0)/0x0(0)
Last flood scan length is 1, maximum is 1
Last flood scan time is 0 msec, maximum is 0 msec
Neighbor Count is 1, Adjacent neighbor count is 1
Adjacent with neighbor 172.16.10.1 (Designated Router)
Suppress hello for 0 neighbor(s)
Serial0/0/0 is up, line protocol is up
Internet address is 172.16.20.1/24, Area 0
Process ID 101, Router ID 172.16.20.1, Network Type POINT-TO-POINT, Cost: 64
Transmit Delay is 1 sec, State POINT-TO-POINT,
Timer intervals configured, Hello 10, Dead 40, Wait 40, Retransmit 5
Hello due in 00:00:04
Index 2/2, flood queue length 0
Next 0x0(0)/0x0(0)
Last flood scan length is 1, maximum is 1
Last flood scan time is 0 msec, maximum is 0 msec
Suppress hello for 0 neighbor(s)
still looks good; same as before.... On to LabC router
LabC
LabC(config)#
router ospf 102
LabC(config-router)#
net 172.16.20.2 0.0.0.0 area 0
LabC(config-router)#
net 172.16.30.1 0.0.0.0 area 0
LabC(config-router)#
net 172.16.40.1 0.0.0.0 area 0
01:33:54: %OSPF-5-ADJCHG: Process 102, Nbr 172.16.20.1
on Serial0/0/0 from LOADING to FULL, Loading Done
LabC#
show ip ospf neighbor
[no output]
And here is where I ran into trouble. The show ip ospf neighbor command returns nothing. How can
that be?
After awhile I realized it is due to a misconfiguration in the topology.
For Lab C, I programmed the interfaces as follows:
LabC(config)#
int f0/0
LabC(config-if)#
ip addr 172.16.30.1 255.255.255.0
LabC(config-if)#
no shut
LabC(config-if)#
int s0/0/0
LabC(config-if)#
ip addr 172.16.20.2 255.255.255.0
LabC(config-if)#
no shut
LabC(config-if)#
int s0/0/1
LabC(config-if)#
ip addr 172.16.40.1 255.255.255.0
LabC(config-if)#
no shut
and again here is the topology for that router:
but here is what it SHOULD HAVE looked like (as it did the first time I built it)
S0/0/0 and S0/0/1 are swapped. When I gave the IP 172.16.20.2 to s/0/0/0, thinking that was the interface on the left side
which faces Lab B, I was actually giving 172.16.20.2 to the right side, facing LabC (which has no OSPF configs yet.)
Since the left side got got the IP intended for the right side which was 172.16.40.1
the inverse also occured-
the right side got the IP intended for the left which was 172.16.20.2
LabC left side should have been
s0/0/0 with 20.2
and LabC right side should have been
s0/0/1 with 40.1
The correct IPs were mapped to the correct interfaces. But the mistake happened before I even programmed them.
When I made the connections from LabB to LabC and from LabD to LabC, I plugged then into the wrong ports.
Interestingly.. not only is this causing OSPF to not see B as a neighbor from C.. but B and C cannot ping eachother either.
@B the config is 172.16.20.1/24 @ S0/0/0
@C the config is 172.16.40.1/24 @ S/0/0/1
meaning they are not even on the same network! But the system is not throwing any errors or bringing it to my attention.
It just fails to connect.
To correct the issue, I simply deleted those two links and re-created them. Worth noting, I used the auto select cable here,
which does not ask which interface you want to use when attaching. Earlier I must have plugged the right side first, and
auto select plugged into 0/0/0.
This time I plugged into left side first.
Now LabC OSPF data is reading out correctly...
LabC
LabC(config)#
router ospf 102
LabC(config-router)#
net 172.16.20.2 0.0.0.0 area 0
LabC(config-router)#
net 172.16.30.1 0.0.0.0 area 0
LabC(config-router)#
net 172.16.40.1 0.0.0.0 area 0
01:33:54: %OSPF-5-ADJCHG: Process 102, Nbr 172.16.20.1
on Serial0/0/0 from LOADING to FULL, Loading Done
LabC#
show ip ospf neighbor
Neighbor ID Pri State Dead Time Address Interface
172.16.20.1 0 FULL/ - 00:00:30 172.16.20.1 Serial0/0/0
LabC#
show ip ospf database
OSPF Router with ID (172.16.40.1) (Process ID 102)
Router Link States (Area 0)
Link ID ADV Router Age Seq# Checksum Link count
172.16.10.1 172.16.10.1 542 0x80000002 0x0067cd 1
172.16.20.1 172.16.20.1 90 0x80000004 0x00a551 3
172.16.40.1 172.16.40.1 37 0x80000004 0x00e47c 4
Net Link States (Area 0)
Link ID ADV Router Age Seq# Checksum
172.16.10.1 172.16.10.1 542 0x80000001 0x00953d
LabC#
show ip ospf interface
Serial0/0/0 is up, line protocol is up
Internet address is 172.16.20.2/24, Area 0
Process ID 102, Router ID 172.16.40.1, Network Type POINT-TO-POINT, Cost: 64
Transmit Delay is 1 sec, State POINT-TO-POINT,
Timer intervals configured, Hello 10, Dead 40, Wait 40, Retransmit 5
Hello due in 00:00:01
Index 1/1, flood queue length 0
Next 0x0(0)/0x0(0)
Last flood scan length is 1, maximum is 1
Last flood scan time is 0 msec, maximum is 0 msec
Neighbor Count is 1 , Adjacent neighbor count is 1
Adjacent with neighbor 172.16.20.1
Suppress hello for 0 neighbor(s)
FastEthernet0/0 is up, line protocol is up
Internet address is 172.16.30.1/24, Area 0
Process ID 102, Router ID 172.16.40.1, Network Type BROADCAST, Cost: 1
Transmit Delay is 1 sec, State DR, Priority 1
Designated Router (ID) 172.16.40.1, Interface address 172.16.30.1
No backup designated router on this network
Timer intervals configured, Hello 10, Dead 40, Wait 40, Retransmit 5
Hello due in 00:00:02
Index 2/2, flood queue length 0
Next 0x0(0)/0x0(0)
Last flood scan length is 1, maximum is 1
Last flood scan time is 0 msec, maximum is 0 msec
Neighbor Count is 0, Adjacent neighbor count is 0
Suppress hello for 0 neighbor(s)
Serial0/0/1 is up, line protocol is up
Internet address is 172.16.40.1/24, Area 0
Process ID 102, Router ID 172.16.40.1, Network Type POINT-TO-POINT, Cost: 64
Transmit Delay is 1 sec, State POINT-TO-POINT,
Timer intervals configured, Hello 10, Dead 40, Wait 40, Retransmit 5
Hello due in 00:00:08
Index 3/3, flood queue length 0
Next 0x0(0)/0x0(0)
Last flood scan length is 1, maximum is 1
Last flood scan time is 0 msec, maximum is 0 msec
Suppress hello for 0 neighbor(s)
Which brings me to the original reason I re-created this topology... I was confused about the LINK COUNTS
here:
OSPF Router with ID (172.16.40.1) (Process ID 102)
Router Link States (Area 0)
Link ID ADV Router Age Seq# Checksum Link count
172.16.10.1 172.16.10.1 542 0x80000002 0x0067cd 1
172.16.20.1 172.16.20.1 90 0x80000004 0x00a551 3
172.16.40.1 172.16.40.1 37 0x80000004 0x00e47c 4
Net Link States (Area 0)
Link ID ADV Router Age Seq# Checksum
172.16.10.1 172.16.10.1 542 0x80000001 0x00953d
The steps of recreating the lab were helpful, but this link answered the question:
Here is the output of each router's command show ip ospf interface as they are
set up one at a time.
LabA - No OSPF at B, C, or D yet
show ip ospf database
OSPF Router with ID (172.16.10.1) (Process ID 100)
Router Link States (Area 0)
Link ID ADV Router Age Seq# Checksum Link count
172.16.10.1 172.16.10.1 44 0x80000001 0x00b24b 1
LabB - No OSPF at C or D yet
show ip ospf database
OSPF Router with ID (172.16.20.1) (Process ID 101)
Router Link States (Area 0)
Link ID ADV Router Age Seq# Checksum Link count
172.16.10.1 172.16.10.1 145 0x80000002 0x0067cd 1
172.16.20.1 172.16.20.1 32 0x80000003 0x006e8f 2
Net Link States (Area 0)
Link ID ADV Router Age Seq# Checksum
172.16.10.1 172.16.10.1 145 0x80000001 0x00953d
the 20.2 interface on this router has 2 ospf links.
The left-facing out to RA, a crossover cable
The right-facing out to RC, a serial cable.
If the solution I found is correct, why is this serial link not being counted twice? The solution (I think)
is revealed after the configuration of the next router...
LabC - No OSPF at D yet
show ip ospf database
OSPF Router with ID (172.16.40.1) (Process ID 102)
Router Link States (Area 0)
Link ID ADV Router Age Seq# Checksum Link count
172.16.10.1 172.16.10.1 542 0x80000002 0x0067cd 1
172.16.20.1 172.16.20.1 90 0x80000004 0x00a551 3
172.16.40.1 172.16.40.1 37 0x80000004 0x00e47c 4
Net Link States (Area 0)
Link ID ADV Router Age Seq# Checksum
172.16.10.1 172.16.10.1 542 0x80000001 0x00953d
NOW we can see that the 20.1 link, which is the right-facing interface on LabB.. aka the router ID..
has THREE OSPF links.
Nothing changed on the left side of B. But on the right side, we now have an active OSPF router at the
other end of the link. This leads me to believe that the forum post was correct that 'serial links are counted twice',
but, more specifically, BOTH ENDS of the serial(PPP) link are counted... IF there is an OSPF router on each end.
This is backed up by the fact that LabC, OSPF id 40.1, has four OSPF links. The top-facing link to the 30
network DOES count.. even though it has no OSPF router on the other end. It counts because it's not a serial link.
The requirement of having an OSPF router on the other end for an interface to count here, only applies
to serial links. And pertains to BOTH ends of the link being counted.
In LabC's case, we have one serial at left, being counted twice. One ethernet at top, being counted once. And
one serial at right only being counted once because LabD is not active with OSPF yet.
If this is correct, then we should see Lab C's 40.1 count go to 5 after LabD is set for OSPF....
LabD - all 4 routers have OSPF
show ip ospf database
OSPF Router with ID (172.16.50.1) (Process ID 103)
Router Link States (Area 0)
Link ID ADV Router Age Seq# Checksum Link count
172.16.10.1 172.16.10.1 785 0x80000002 0x0067cd 1
172.16.20.1 172.16.20.1 333 0x80000004 0x00a551 3
172.16.40.1 172.16.40.1 111 0x80000005 0x00013b 5
172.16.50.1 172.16.50.1 53 0x80000003 0x001023 3
Net Link States (Area 0)
Link ID ADV Router Age Seq# Checksum
172.16.10.1 172.16.10.1 785 0x80000001 0x00953d
and back to LabC.....
show ip ospf database
OSPF Router with ID (172.16.40.1) (Process ID 102)
Router Link States (Area 0)
Link ID ADV Router Age Seq# Checksum Link count
172.16.10.1 172.16.10.1 1174 0x80000002 0x0067cd 1
172.16.20.1 172.16.20.1 722 0x80000004 0x00a551 3
172.16.40.1 172.16.40.1 500 0x80000005 0x00013b 5
172.16.50.1 172.16.50.1 441 0x80000003 0x001023 3
Net Link States (Area 0)
Link ID ADV Router Age Seq# Checksum
172.16.10.1 172.16.10.1 1174 0x80000001 0x00953d
Looks good! The link count for each router makes sense if you count the serial interfaces twice (one for each end).
the OSPF databases now match across all 4 routers.
NOTE that this is a database of routers, identified by
router ID. It is not a topology that lists routers AND routes, like in
the "equivalent" eigrp command show eigrp topology
Note that the .30 network is NOT represented here.
LabA#
show ip ospf database
OSPF Router with ID (172.16.10.1) (Process ID 100)
Router Link States (Area 0)
Link ID ADV Router Age Seq# Checksum Link count
172.16.10.1 172.16.10.1 1138 0x80000002 0x0067cd 1
172.16.20.1 172.16.20.1 686 0x80000004 0x00a551 3
172.16.40.1 172.16.40.1 463 0x80000005 0x00013b 5
172.16.50.1 172.16.50.1 404 0x80000003 0x001023 3
Net Link States (Area 0)
Link ID ADV Router Age Seq# Checksum
172.16.10.1 172.16.10.1 1138 0x80000001 0x00953d
LabB#
show ip ospf database
OSPF Router with ID (172.16.20.1) (Process ID 101)
Router Link States (Area 0)
Link ID ADV Router Age Seq# Checksum Link count
172.16.10.1 172.16.10.1 1151 0x80000002 0x0067cd 1
172.16.20.1 172.16.20.1 699 0x80000004 0x00a551 3
172.16.40.1 172.16.40.1 476 0x80000005 0x00013b 5
172.16.50.1 172.16.50.1 417 0x80000003 0x001023 3
Net Link States (Area 0)
Link ID ADV Router Age Seq# Checksum
172.16.10.1 172.16.10.1 1151 0x80000001 0x00953d
LabC#
show ip ospf database
OSPF Router with ID (172.16.40.1) (Process ID 102)
Router Link States (Area 0)
Link ID ADV Router Age Seq# Checksum Link count
172.16.10.1 172.16.10.1 1174 0x80000002 0x0067cd 1
172.16.20.1 172.16.20.1 722 0x80000004 0x00a551 3
172.16.40.1 172.16.40.1 500 0x80000005 0x00013b 5
172.16.50.1 172.16.50.1 441 0x80000003 0x001023 3
Net Link States (Area 0)
Link ID ADV Router Age Seq# Checksum
172.16.10.1 172.16.10.1 1174 0x80000001 0x00953d
LabD#
show ip ospf database
OSPF Router with ID (172.16.50.1) (Process ID 103)
Router Link States (Area 0)
Link ID ADV Router Age Seq# Checksum Link count
172.16.10.1 172.16.10.1 785 0x80000002 0x0067cd 1
172.16.20.1 172.16.20.1 333 0x80000004 0x00a551 3
172.16.40.1 172.16.40.1 111 0x80000005 0x00013b 5
172.16.50.1 172.16.50.1 53 0x80000003 0x001023 3
Net Link States (Area 0)
Link ID ADV Router Age Seq# Checksum
172.16.10.1 172.16.10.1 785 0x80000001 0x00953d
Below is our routing tables with OSPF data. We do see the .30 network here.
Everyone can reach it:
LabA via LabB's 10.2
LabB via LabC's 20.2
LabC via direct connection
LabD via LabC's 40.1
LabA#
show ip route
172.16.0.0/16 is variably subnetted, 6 subnets, 2 masks
C 172.16.10.0/24 is directly connected, FastEthernet0/0
L 172.16.10.1/32 is directly connected, FastEthernet0/0
O 172.16.20.0/24 [110/65] via 172.16.10.2, 00:28:03, FastEthernet0/0
O 172.16.30.0/24 [110/66] via 172.16.10.2, 00:21:35, FastEthernet0/0
O 172.16.40.0/24 [110/129] via 172.16.10.2, 00:21:25, FastEthernet0/0
O 172.16.50.0/24 [110/130] via 172.16.10.2, 00:17:40, FastEthernet0/0
LabB#
show ip route
172.16.0.0/16 is variably subnetted, 7 subnets, 2 masks
C 172.16.10.0/24 is directly connected, FastEthernet0/0
L 172.16.10.2/32 is directly connected, FastEthernet0/0
C 172.16.20.0/24 is directly connected, Serial0/0/0
L 172.16.20.1/32 is directly connected, Serial0/0/0
O 172.16.30.0/24 [110/65] via 172.16.20.2, 00:27:04, Serial0/0/0
O 172.16.40.0/24 [110/128] via 172.16.20.2, 00:26:54, Serial0/0/0
O 172.16.50.0/24 [110/129] via 172.16.20.2, 00:23:09, Serial0/0/0
LabC#
show ip route
172.16.0.0/16 is variably subnetted, 8 subnets, 2 masks
O 172.16.10.0/24 [110/65] via 172.16.20.1, 00:27:52, Serial0/0/0
C 172.16.20.0/24 is directly connected, Serial0/0/0
L 172.16.20.2/32 is directly connected, Serial0/0/0
C 172.16.30.0/24 is directly connected, FastEthernet0/0
L 172.16.30.1/32 is directly connected, FastEthernet0/0
C 172.16.40.0/24 is directly connected, Serial0/0/1
L 172.16.40.1/32 is directly connected, Serial0/0/1
O 172.16.50.0/24 [110/65] via 172.16.40.2, 00:23:36, Serial0/0/1
LabD#
show ip route
172.16.0.0/16 is variably subnetted, 7 subnets, 2 masks
O 172.16.10.0/24 [110/129] via 172.16.40.1, 00:25:20, Serial0/0/0
O 172.16.20.0/24 [110/128] via 172.16.40.1, 00:25:20, Serial0/0/0
O 172.16.30.0/24 [110/65] via 172.16.40.1, 00:25:20, Serial0/0/0
C 172.16.40.0/24 is directly connected, Serial0/0/0
L 172.16.40.2/32 is directly connected, Serial0/0/0
C 172.16.50.0/24 is directly connected, FastEthernet0/0
L 172.16.50.1/32 is directly connected, FastEthernet0/0
moving on.......
9.5 - OSPF DR and BDR Elections
EachRouter(config)#
hostname X (A, B, or C)
EachRouter(config)#
line con 0
EachRouter(config-line)#
exec-timeout 0 0
A(config)#
int f0/0
A(config-if)#
ip addr 10.1.1.1 255.255.255.0
A(config-if)#
no shut
A(config)#
router ospf 12345
A(config-router)#
net 10.1.1.0 0.0.0.255 area 0
00:23:30: %OSPF-5-ADJCHG: Process 12345, Nbr 10.1.1.3 on FastEthernet0/0 from LOADING to FULL, Loading Done
00:23:30: %OSPF-5-ADJCHG: Process 12345, Nbr 10.1.1.2 on FastEthernet0/0 from LOADING to FULL, Loading Done
A#
show ip ospf int
note this output was generated AFTER all 3 routers set for OSPF
FastEthernet0/0 is up, line protocol is up
Internet address is 10.1.1.1/24, Area 0
Process ID 12345, Router ID 10.1.1.1, Network Type BROADCAST, Cost: 1
Transmit Delay is 1 sec, State DROTHER, Priority 1
Designated Router (ID) 10.1.1.3, Interface address 10.1.1.3
Backup Designated Router (ID) 10.1.1.2, Interface address 10.1.1.2
Timer intervals configured, Hello 10, Dead 40, Wait 40, Retransmit 5
Hello due in 00:00:04
Index 1/1, flood queue length 0
Next 0x0(0)/0x0(0)
Last flood scan length is 1, maximum is 1
Last flood scan time is 0 msec, maximum is 0 msec
Neighbor Count is 2, Adjacent neighbor count is 2
Adjacent with neighbor 10.1.1.3 (Designated Router)
Adjacent with neighbor 10.1.1.2 (Backup Designated Router)
Suppress hello for 0 neighbor(s)
A(config-if)#shut
A(config-if)#
%LINK-5-CHANGED: Interface FastEthernet0/0, changed state to administratively down
%LINEPROTO-5-UPDOWN: Line protocol on Interface FastEthernet0/0, changed state to down
00:40:28: %OSPF-5-ADJCHG: Process 12345, Nbr 10.1.1.2 on FastEthernet0/0 from FULL to DOWN, Neighbor Down: Interface down or detached
00:40:28: OSPF: Build router LSA for area 0, router ID 10.1.1.1, seq 0xffffffff80000003
00:40:28: %OSPF-5-ADJCHG: Process 12345, Nbr 10.1.1.3 on FastEthernet0/0 from FULL to DOWN, Neighbor Down: Interface down or detached
00:40:28: OSPF: Build router LSA for area 0, router ID 10.1.1.1, seq 0xffffffff80000004
00:40:28: OSPF: Build router LSA for area 0, router ID 10.1.1.1, seq 0xffffffff80000004
A(config-if)#no shut
A(config-if)#
%LINK-5-CHANGED: Interface FastEthernet0/0, changed state to up
%LINEPROTO-5-UPDOWN: Line protocol on Interface FastEthernet0/0, changed state to up
00:40:48: OSPF: Build router LSA for area 0, router ID 10.1.1.1, seq 0xffffffff80000004
00:41:27: OSPF: Backup seen Event before WAIT timer on FastEthernet0/0
00:41:27: OSPF: DR/BDR election on FastEthernet0/0
00:41:27: OSPF: Elect BDR 10.1.1.2
00:41:27: OSPF: Elect DR 10.1.1.3
00:41:27: DR: 10.1.1.3 (Id) BDR: 10.1.1.2 (Id)
00:41:27: OSPF: Send DBD to 10.1.1.3 on FastEthernet0/0 seq 0x5accb8e2 opt 0x00 flag 0x7 len 32
B(config)#
int f0/0
B(config-if)#
ip addr 10.1.1.2 255.255.255.0
B(config-if)#
no shut
B(config)#
router ospf 12345
B(config-router)#
net 10.1.1.0 0.0.0.255 area 0
00:23:29: %OSPF-5-ADJCHG: Process 12345, Nbr 10.1.1.3 on FastEthernet0/0 from LOADING to FULL, Loading Done
00:23:29: %OSPF-5-ADJCHG: Process 12345, Nbr 10.1.1.1 on FastEthernet0/0 from LOADING to FULL, Loading Done
B#
show ip ospf int
note this output was generated AFTER all 3 routers set for OSPF
FastEthernet0/0 is up, line protocol is up
Internet address is 10.1.1.2/24, Area 0
Process ID 12345, Router ID 10.1.1.2, Network Type BROADCAST, Cost: 1
Transmit Delay is 1 sec, State BDR, Priority 1
Designated Router (ID) 10.1.1.3, Interface address 10.1.1.3
Backup Designated Router (ID) 10.1.1.2, Interface address 10.1.1.2
Timer intervals configured, Hello 10, Dead 40, Wait 40, Retransmit 5
Hello due in 00:00:05
Index 1/1, flood queue length 0
Next 0x0(0)/0x0(0)
Last flood scan length is 1, maximum is 1
Last flood scan time is 0 msec, maximum is 0 msec
Neighbor Count is 2, Adjacent neighbor count is 2
Adjacent with neighbor 10.1.1.1
Adjacent with neighbor 10.1.1.3 (Designated Router)
Suppress hello for 0 neighbor(s)
B#debug ip ospf adj
OSPF adjacency events debugging is on
B#
00:39:21: OSPF: DR/BDR election on FastEthernet0/0
00:39:21: OSPF: Elect BDR 10.1.1.2
00:39:21: OSPF: Elect DR 10.1.1.3
00:39:21: DR: 10.1.1.3 (Id) BDR: 10.1.1.2 (Id)
00:41:01: %OSPF-5-ADJCHG: Process 12345, Nbr 10.1.1.1 on FastEthernet0/0 from FULL to DOWN, Neighbor Down: Dead timer expired
00:41:01: %OSPF-5-ADJCHG: Process 12345, Nbr 10.1.1.1 on FastEthernet0/0 from FULL to DOWN, Neighbor Down: Interface down or detached
00:41:01: OSPF: Build router LSA for area 0, router ID 10.1.1.2, seq 0xffffffff80000003
00:41:01: OSPF: DR/BDR election on FastEthernet0/0
00:41:01: OSPF: Elect BDR 10.1.1.2
00:41:01: OSPF: Elect DR 10.1.1.3
C(config)#
int f0/0
C(config-if)#
ip addr 10.1.1.3 255.255.255.0
C(config-if)#
no shut
C(config)#
router ospf 12345
C(config-router)#
net 10.1.1.0 0.0.0.255 area 0
00:23:27: %OSPF-5-ADJCHG: Process 12345, Nbr 10.1.1.1 on FastEthernet0/0 from LOADING to FULL, Loading Done
00:23:27: %OSPF-5-ADJCHG: Process 12345, Nbr 10.1.1.2 on FastEthernet0/0 from LOADING to FULL, Loading Done
C#
show ip ospf int
note this output was generated AFTER all 3 routers set for OSPF
FastEthernet0/0 is up, line protocol is up
Internet address is 10.1.1.3/24, Area 0
Process ID 12345, Router ID 10.1.1.3, Network Type BROADCAST, Cost: 1
Transmit Delay is 1 sec, State DR, Priority 1
Designated Router (ID) 10.1.1.3, Interface address 10.1.1.3
Backup Designated Router (ID) 10.1.1.2, Interface address 10.1.1.2
Timer intervals configured, Hello 10, Dead 40, Wait 40, Retransmit 5
Hello due in 00:00:00
Index 1/1, flood queue length 0
Next 0x0(0)/0x0(0)
Last flood scan length is 1, maximum is 1
Last flood scan time is 0 msec, maximum is 0 msec
Neighbor Count is 2, Adjacent neighbor count is 2
Adjacent with neighbor 10.1.1.1
Adjacent with neighbor 10.1.1.2 (Backup Designated Router)
Suppress hello for 0 neighbor(s)
C#debug ip ospf adj
OSPF adjacency events debugging is on
C#
00:39:19: OSPF: DR/BDR election on FastEthernet0/0
00:39:19: OSPF: Elect BDR 10.1.1.2
00:39:19: OSPF: Elect DR 10.1.1.3
00:39:19: DR: 10.1.1.3 (Id) BDR: 10.1.1.2 (Id)
00:40:59: %OSPF-5-ADJCHG: Process 12345, Nbr 10.1.1.1 on FastEthernet0/0 from FULL to DOWN, Neighbor Down: Dead timer expired
00:40:59: %OSPF-5-ADJCHG: Process 12345, Nbr 10.1.1.1 on FastEthernet0/0 from FULL to DOWN, Neighbor Down: Interface down or detached
00:40:59: OSPF: Build router LSA for area 0, router ID 10.1.1.3, seq 0xffffffff80000003
00:40:59: OSPF: Build net LSA for area 0, router ID 10.1.1.3, seq 0xffffffff80000003
00:40:59: OSPF: DR/BDR election on FastEthernet0/0
00:40:59: OSPF: Elect BDR 10.1.1.2
00:40:59: OSPF: Elect DR 10.1.1.3
DR and BDR automtically set based on higest IP address
Note our network type is BROADCAST because we're using ethernet interfaces...
it would be point-to-point if using a serial connection
we want to manually overide the priority of the router. ZERO priority means it wont participate in the election process
MAX priority of 255 means no other router can beat it for DR
We'll set the priority for router A to 3.
It will beome the DR only after we shut/no shut the interface router
AND
manually power on/off the other two routers
A(config)#
int f0/0
A(config-int)#
ip ospf priority 3
A(config-int)#
shut
A(config-int)#
no shut
A#
debug ip ospf adj
B#
debug ip ospf adj
00:05:50: OSPF: DR/BDR election on FastEthernet0/0
00:05:50: OSPF: Elect BDR 10.1.1.2
00:05:50: OSPF: Elect DR 10.1.1.1
00:05:50: OSPF: Elect BDR 10.1.1.2
00:05:50: OSPF: Elect DR 10.1.1.1
00:05:50: DR: 10.1.1.1 (Id) BDR: 10.1.1.2 (Id)
00:05:50: OSPF: Send DBD to 10.1.1.1 on FastEthernet0/0 seq 0x10164ebb opt 0x00 flag 0x7 len 32
00:05:50: OSPF: Build router LSA for area 0, router ID 10.1.1.2, seq 0xffffffff80000002
00:05:52: OSPF: Rcv DBD from 10.1.1.1 on FastEthernet0/0 seq 0x20368093 opt 0x00 flag 0x7 len 32 mtu 1500 state EXSTART
00:05:52: OSPF: First DBD and we are not SLAVE
00:05:55: OSPF: Send DBD to 10.1.1.1 on FastEthernet0/0 seq 0x10164ebb opt 0x00 flag 0x7 len 32
00:05:55: OSPF: Rcv DBD from 10.1.1.1 on FastEthernet0/0 seq 0x10164ebb opt 0x00 flag 0x2 len 112 mtu 1500 state EXSTART
00:05:55: OSPF: NBR Negotiation Done. We are the MASTER
00:05:55: OSPF: Send DBD to 10.1.1.1 on FastEthernet0/0 seq 0x10164ebc opt 0x00 flag 0x3 len 52
00:05:55: OSPF: Rcv DBD from 10.1.1.1 on FastEthernet0/0 seq 0x10164ebc opt 0x00 flag 0x0 len 32 mtu 1500 state EXCHANGE
00:05:55: OSPF: Send DBD to 10.1.1.1 on FastEthernet0/0 seq 0x10164ebd opt 0x00 flag 0x1 len 32
00:05:55: OSPF: Rcv DBD from 10.1.1.1 on FastEthernet0/0 seq 0x10164ebd opt 0x00 flag 0x0 len 32 mtu 1500 state EXCHANGE
00:05:55: Exchange Done with 10.1.1.1 on FastEthernet0/0
00:05:55: OSPF: Database request to 10.1.1.1
00:05:55: OSPF: sent LS REQ packet to 10.1.1.1, length 36
00:05:55: OSPF: Rcv DBD from 10.1.1.1 on FastEthernet0/0 seq 0x10164ebd opt 0x00 flag 0x0 len 32 mtu 1500 state LOADING
00:05:55: Synchronized with with 10.1.1.1 on FastEthernet0/0, state FULL
00:05:55: %OSPF-5-ADJCHG: Process 12345, Nbr 10.1.1.1 on FastEthernet0/0 from LOADING to FULL, Loading Done
00:05:55: OSPF: Build router LSA for area 0, router ID 10.1.1.2, seq 0xffffffff80000002
C#
debug ip ospf adj
00:06:13: OSPF: DR/BDR election on FastEthernet0/0
00:06:13: OSPF: Elect BDR 10.1.1.2
00:06:13: OSPF: Elect DR 10.1.1.1
00:06:13: DR: 10.1.1.1 (Id) BDR: 10.1.1.2 (Id)
00:06:13: OSPF: Send DBD to 10.1.1.1 on FastEthernet0/0 seq 0x1cc5536d opt 0x00 flag 0x7 len 32
00:06:13: OSPF: Send DBD to 10.1.1.2 on FastEthernet0/0 seq 0x3d51ca66 opt 0x00 flag 0x7 len 32
00:06:13: OSPF: Build router LSA for area 0, router ID 10.1.1.3, seq 0xffffffff80000002
00:06:17: OSPF: Rcv DBD from 10.1.1.1 on FastEthernet0/0 seq 0x6b532eec opt 0x00 flag 0x7 len 32 mtu 1500 state EXSTART
00:06:17: OSPF: First DBD and we are not SLAVE
00:06:17: OSPF: Rcv DBD from 10.1.1.2 on FastEthernet0/0 seq 0x783110f4 opt 0x00 flag 0x7 len 32 mtu 1500 state EXSTART
00:06:17: OSPF: First DBD and we are not SLAVE
00:06:18: OSPF: Send DBD to 10.1.1.2 on FastEthernet0/0 seq 0x3d51ca66 opt 0x00 flag 0x7 len 32
00:06:18: OSPF: Send DBD to 10.1.1.1 on FastEthernet0/0 seq 0x1cc5536d opt 0x00 flag 0x7 len 32
00:06:18: OSPF: Rcv DBD from 10.1.1.2 on FastEthernet0/0 seq 0x3d51ca66 opt 0x00 flag 0x2 len 132 mtu 1500 state EXSTART
00:06:18: OSPF: NBR Negotiation Done. We are the MASTER
00:06:18: OSPF: Send DBD to 10.1.1.2 on FastEthernet0/0 seq 0x3d51ca67 opt 0x00 flag 0x3 len 52
00:06:18: OSPF: Rcv DBD from 10.1.1.1 on FastEthernet0/0 seq 0x1cc5536d opt 0x00 flag 0x2 len 132 mtu 1500 state EXSTART
00:06:18: OSPF: NBR Negotiation Done. We are the MASTER
00:06:18: OSPF: Send DBD to 10.1.1.1 on FastEthernet0/0 seq 0x1cc5536e opt 0x00 flag 0x3 len 52
00:06:18: OSPF: Rcv DBD from 10.1.1.2 on FastEthernet0/0 seq 0x3d51ca67 opt 0x00 flag 0x0 len 32 mtu 1500 state EXCHANGE
00:06:18: OSPF: Send DBD to 10.1.1.2 on FastEthernet0/0 seq 0x3d51ca68 opt 0x00 flag 0x1 len 32
00:06:18: OSPF: Rcv DBD from 10.1.1.1 on FastEthernet0/0 seq 0x1cc5536e opt 0x00 flag 0x0 len 32 mtu 1500 state EXCHANGE
00:06:18: OSPF: Send DBD to 10.1.1.1 on FastEthernet0/0 seq 0x1cc5536f opt 0x00 flag 0x1 len 32
00:06:18: OSPF: Rcv DBD from 10.1.1.2 on FastEthernet0/0 seq 0x3d51ca68 opt 0x00 flag 0x0 len 32 mtu 1500 state EXCHANGE
00:06:18: Exchange Done with 10.1.1.2 on FastEthernet0/0
00:06:18: OSPF: Database request to 10.1.1.2
00:06:18: OSPF: sent LS REQ packet to 10.1.1.2, length 48
00:06:18: OSPF: Rcv DBD from 10.1.1.1 on FastEthernet0/0 seq 0x1cc5536f opt 0x00 flag 0x0 len 32 mtu 1500 state EXCHANGE
verify on all three routers
A#
show ip ospf interface f0/0
FastEthernet0/0 is up, line protocol is up
Internet address is 10.1.1.1/24, Area 0
Process ID 12345, Router ID 10.1.1.1, Network Type BROADCAST, Cost: 1
Transmit Delay is 1 sec, State DR, Priority 3
Designated Router (ID) 10.1.1.1, Interface address 10.1.1.1
Backup Designated Router (ID) 10.1.1.2, Interface address 10.1.1.2
Timer intervals configured, Hello 10, Dead 40, Wait 40, Retransmit 5
Hello due in 00:00:09
Index 1/1, flood queue length 0
Next 0x0(0)/0x0(0)
Last flood scan length is 1, maximum is 1
Last flood scan time is 0 msec, maximum is 0 msec
Neighbor Count is 2, Adjacent neighbor count is 2
Adjacent with neighbor 10.1.1.2 (Backup Designated Router)
Adjacent with neighbor 10.1.1.3
Suppress hello for 0 neighbor(s)
A#
show ip ospf neighbor
Neighbor ID Pri State Dead Time Address Interface
10.1.1.2 1 FULL/BDR 00:00:37 10.1.1.2 FastEthernet0/0
10.1.1.3 1 FULL/DROTHER 00:00:30 10.1.1.3 FastEthernet0/0
B#
show ip ospf interface f0/0
FastEthernet0/0 is up, line protocol is up
Internet address is 10.1.1.2/24, Area 0
Process ID 12345, Router ID 10.1.1.2, Network Type BROADCAST, Cost: 1
Transmit Delay is 1 sec, State BDR, Priority 1
Designated Router (ID) 10.1.1.1, Interface address 10.1.1.1
Backup Designated Router (ID) 10.1.1.2, Interface address 10.1.1.2
Timer intervals configured, Hello 10, Dead 40, Wait 40, Retransmit 5
Hello due in 00:00:08
Index 1/1, flood queue length 0
Next 0x0(0)/0x0(0)
Last flood scan length is 1, maximum is 1
Last flood scan time is 0 msec, maximum is 0 msec
Neighbor Count is 2, Adjacent neighbor count is 2
Adjacent with neighbor 10.1.1.1 (Designated Router)
Adjacent with neighbor 10.1.1.3
Suppress hello for 0 neighbor(s)
B#
show ip ospf neighbor
Neighbor ID Pri State Dead Time Address Interface
10.1.1.1 3 FULL/DR 00:00:35 10.1.1.1 FastEthernet0/0
10.1.1.3 1 FULL/DROTHER 00:00:31 10.1.1.3 FastEthernet0/0
C#
show ip ospf interface f0/0
FastEthernet0/0 is up, line protocol is up
Internet address is 10.1.1.3/24, Area 0
Process ID 12345, Router ID 10.1.1.3, Network Type BROADCAST, Cost: 1
Transmit Delay is 1 sec, State DROTHER, Priority 1
Designated Router (ID) 10.1.1.1, Interface address 10.1.1.1
Backup Designated Router (ID) 10.1.1.2, Interface address 10.1.1.2
Timer intervals configured, Hello 10, Dead 40, Wait 40, Retransmit 5
Hello due in 00:00:06
Index 1/1, flood queue length 0
Next 0x0(0)/0x0(0)
Last flood scan length is 1, maximum is 1
Last flood scan time is 0 msec, maximum is 0 msec
Neighbor Count is 2, Adjacent neighbor count is 2
Adjacent with neighbor 10.1.1.1 (Designated Router)
Adjacent with neighbor 10.1.1.2 (Backup Designated Router)
Suppress hello for 0 neighbor(s)
C#
show ip ospf neighbor/span>
Neighbor ID Pri State Dead Time Address Interface
10.1.1.1 3 FULL/DR 00:00:35 10.1.1.1 FastEthernet0/0
10.1.1.2 1 FULL/BDR 00:00:37 10.1.1.2 FastEthernet0/0
Router1 is the DR with priority 3
still need more work to understand the output of the defbu ospf adj
Chapter 9 Review Questions
1. There are three possible routes for a router to reach a destination network:
OSPF with a metric of 782
RIPv2 with a metric of 4
EIGRP with a composite metric of 20514560
Which route will be installed in the routing table?
EIGRP because it has the lowest Administrative Distance, and AD is always used before metric
ADs are:
ExternalEIGRP 170
RIP 120
OSPF 110
IGRP 100
EIGRP 90
Static 1
Connected 0
2. Which EIGRP information is held in RAM and maintained through the use of Hello and update packets?
Neighbor table
and
toplogy table
3. Describe the process identifier that is used to run OSPF on a router
The OSPF process id is only locally significant. A random number can be selected. But it's required in order to identify
a unique OSPF database instance. You can use the same, or a different number on each router, doesnt matter.
Any number can be used from 1 to 65,535. Process ID is supplied as an argument to the command router ospf
NOT to be confused with the area number which can be any number up to 4 billion. The area id identifies a logical grouping of routers.
area id is supplied as argument to the OSPF network id and mask command
Ex:
R1(config)#
router ospf 12345
R1(config-router)#
net 10.1.1.0 0.0.0.255 area 0
4. Where are EIGRP successor routes stored?
EIGRP succesor routers are stored in the routing table. The "succesor" is the successful or primary route.
The successor route is ALSO listed in the topology table,
The feasible successor is a BACKUP route and will ONLY be listed in the topology table, unless the successor route fails,
in which case the feasible successor would become the successor
Note that my EIGRP setup doesnt seem to folow this.
CTRL-F jump to "remotely connected via remote ingress ip address"
the book states that EIGRP is automatically load-balancing our two links from R1 to corp.. is this why there is no feasible successor here?
I did some research and found that in our case, we are not using a Feasible Successor. You CAN have two Successors with equal metric, in which case EIGRP will
automatically load-balance.
But I wanted to find out what a Feasible Successor actually looks like in the EIGRP topology table..
Kevin Wallace EIGRP article
Conclusion:
EIGRP topology table wouldnt specifically say "Feasible Successor", but you would know by two routes appearing, one with a lower metric.
In my topology we have two equal-metric links and they are both considered "Successors". EIGRP uses them equally (load-balanced)
Corp#
show ip eigrp toplogy
[cut]
P 172.16.10.0/24, 1 successors, FD is 28160
via 10.1.5.2 (28160/25600), FastEthernet0/0
P 192.168.10.0/24, 2 successors, FD is 2172416
via 10.1.3.2 (2172416/28160), Serial0/0/1
via 10.1.2.2 (2172416/28160), Serial0/0/0
P 192.168.20.0/24, 2 successors, FD is 2172416
via 10.1.3.2 (2172416/28160), Serial0/0/1
via 10.1.2.2 (2172416/28160), Serial0/0/0
P 192.168.30.0/24, 1 successors, FD is 2172416
via 10.1.4.2 (2172416/28160), Serial0/1/0
P 192.168.40.0/24, 1 successors, FD is 2172416
via 10.1.4.2 (2172416/28160), Serial0/1/0
5. Which command will display all the EIGRP feasible successor routes to a known router.
show ip eigrp topology
6. Find the configuration error. You type the following into your router, but dont see any routes in the routing table?
Router(config)#
router ospf 1
Router(config-router)#
network 10.0.0.0 255.0.0.0
wrong wildcard mask
instead, could have used
0.255.255.255
or
0.0.0.255
the point is we need to specify the first octet as "allowed" into our OSPF config with a 0 mask.
The remaining bits are 'dont care' bits aka 'wildcard' aka 255
7. Which three protocols support VLSM, summarization, and discontigous networking?
RIPv2
EIGRP
OSPF
all 3 build and mainting routing tables, provide classless routing which allows VLSM, summarization, and discontigous networks
RIPv1 and IGRP build/maintain routing tables, but dont offer classless routing
8. Which are true regarding OSPF areas?
the 'backbone' is area 0
if using other areas, they all must directly connect to area 0
9. Which two network types have a designated router and a backup designated router?
Broadcast
NBMA- Non broadcast multi access. Ex: Frame Relay
network types that DO NOT use DR/BDR:
point to point
broadcast multipoint
10. You need to configure a router with a distance-vector protocol that allows classless routing. Which to use?
EIGRP is considered 'advanced distance vector' (ripv2 wasnt an option)
11. You need the IP address of the devices with which the router has established an adjacency.
Also, the retransmit interval and the queue counts for the adjacent routers need to be checked. What command will display the required information?
show ip eigrp neighbors
WRONG: show ip eigrp adjacency - there is no such command.. the word 'adjacency' is only used with debug ip OSPF adjacency
here are the possible commands for show ip eigrp and debug ip eigrp
show ip eigrp ?
interfaces IP-EIGRP interfaces
neighbors IP-EIGRP neighbors
topology IP-EIGRP Topology Table
traffic IP-EIGRP Traffic Statistics
debug ip eigrp ?
summary IP-EIGRP summary route processing
12. You cant establish an adjacency relationship on a common ethernet link between two routers. Based on the output below, what is the cause of the problem?
RouterA#
Ethernet0/0 is up, line protocol is up
Internet Address 172.16.1.2/16, Area 0
Process ID 2, Router ID 172.126.1.2, Network Type BROADCAST, Cost: 10
Transmit Delay is 1 sec, State DR, Priority 1
Designated Router (ID) 172.16.1.2, interface address 172.16.1.1.
No backup designated router on this network
Timer intervals configured, Hello 5, Dead 20, Wait 20, Retransmit 5
Router B#
Internet Address 172.16.1.1/16, Area 0
Process ID 2, Router ID 172.126.1.1, Network Type BROADCAST, Cost: 10
Transmit Delay is 1 sec, State DR, Priority 1
Designated Router (ID) 172.16.1.1, interface address 172.16.1.2.
No backup designated router on this network
Timer intervals configured, Hello 10, Dead 40, Wait 40, Retransmit 5
mismatched timer intervals
OSPF default Hello is 10 and Dead is 40... RouterA was modified
13. Which is true regarding EIGRP successor routes?
Used in the routing table
also appears in the topolgy table
may (or may not) have a backup feasabile successor
14. Which type of OSPF network will elect a backup designated router?
broadcast multi-access
non-broadcast multiaccess
types of network that will NOT elect a BDR:
point to point and brodacast multipoint (hub/spoke topology)
15. Which two commands will place network 10.2.3.0/24 into area 0?
Router(config)#
router ospf 10
Router(config-router)#
network 10.2.3.0 0.0.0.255 area 0
16. With which network type will OSPF establish router adjacencies but not perform the DR/BDR election process?
Point to point
no election process occurs, there is never a DR on point to point
17. What are three reasons for creating OSPF in a heirarchical design?
decrease routing overhead
speed up convergence
confine stability to single areas of the network
18. What is the administrative distance of OSPF?
110
19.
no auto summary
the network is considered discontigous because we have two classful network subnetted (on the left and right),
seperated by a different classful address.
if auto summarization is taking place, the routers cant determine which side is which because both sides would be summarized as
Class B, 172.16.0.0, which isnt specific enough to distinguish between the sides.
20. IF routers in a single area are configured with the same priority value, what value does a router use for the OSPF router ID in the absence of a loopback interface?
The highest IP of any PHSYICAL interface.
Trick question. Highest IP of any LOGICAL interface is an option. And is correct IF you had logical interfaces, but the question
states that any "logical interfaces are absent".
At OSPF startup, the highest IP of *any* active interface on the router becomes the OSPF router ID. If you have loopback (logical) interfaces configured,
one of them (the largest IP) will *override* the phsyical interfaces and the loopback IP becomes the RID.
Reference for which loopback (if multiple) wins:
packetpushers.net
------------------------------------------------------------------------------
END CHAPTER 9
41 hours 2-14 thru 2-28-22
original total 184 hours
14 hours review 12-26 thru 12-28-22
review total hours 46
book page 502/822
184 + 46 = 230 hours * 60 = (13,800 min) / 500 pages =
avg 28 min/page (includes reading and exercises/labs + online research)
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add a secret password
router(config)# enable secret 1234
remove the secret password
router(config)# no enable secret
Note youre not prompted for the secret, since you already had to provide it in order to enter conf mode
add a regular password
router(config)# enable password 4321
Can coexist with the secret password, but the two passwords must be different
----------------------------------------------------------------------
add password for Telnet aka VTY
router(config)# line vty 0 15
16 virtual telnet lines on this router
We can set the whole range, a portion of the range, or a single line
router(config)# login activate authentication
router(config)# password telnet123
----------------------------------------------------------------------
add password for Auxiliary
router(config)# line aux 0 there's only sone aux line
router(config)# login activate authentication
router(config)# password aux123
----------------------------------------------------------------------
add password for Console
router(config)# line console 0 there's only one console line
router(config)# login activate authentication
router(config)# password console123
router(config)# exec-timeout 0 0 min/sec
stop the console from timing out and logging you out
router(config)# logging synchronous
dont overwrite input commands with console messages
router(config)# enable secret 1234
remove the secret password
router(config)# no enable secret
Note youre not prompted for the secret, since you already had to provide it in order to enter conf mode
add a regular password
router(config)# enable password 4321
Can coexist with the secret password, but the two passwords must be different
----------------------------------------------------------------------
add password for Telnet aka VTY
router(config)# line vty 0 15
16 virtual telnet lines on this router
We can set the whole range, a portion of the range, or a single line
router(config)# login activate authentication
router(config)# password telnet123
----------------------------------------------------------------------
add password for Auxiliary
router(config)# line aux 0 there's only sone aux line
router(config)# login activate authentication
router(config)# password aux123
----------------------------------------------------------------------
add password for Console
router(config)# line console 0 there's only one console line
router(config)# login activate authentication
router(config)# password console123
router(config)# exec-timeout 0 0 min/sec
stop the console from timing out and logging you out
router(config)# logging synchronous
dont overwrite input commands with console messages
set router name
router(config)# hostname routerA
------------------------------------------
set motd banner
routerA(config)# banner ?
login Set login banner
motd Set Message of the Day banner
router(config)#
banner motd #
Enter TEXT message. End with the character '#'.
welcome to the router #
router(config)#
------------------------------------------
remove the banner
router(config)# no banner motd
------------------------------------------
set login banner
router(config)# banner login #
Enter TEXT message. End with the character '#'.
please login now #
router(config)#
------------------------------------------
add an IP address to an interface
router(config)# do show interfaces use "do" to enable this command within config mode
GigabitEthernet0/0/0 is administratively down, line protocol is down (disabled)
---cut---
GigabitEthernet0/0/1 is administratively down, line protocol is down (disabled)
---cut---
GigabitEthernet0/0/2 is administratively down, line protocol is down (disabled)
---cut---
Vlan1 is administratively down, line protocol is down
router(config)#
interface g0/0/0
router(config-if)# ip address 1.1.1.1 255.255.0.0
router(config-if)# no shutdown
%LINK-5-CHANGED: Interface GigabitEthernet0/0/0, changed state to up
router(config-if)# do show interfaces
GigabitEthernet0/0/0 is up, line protocol is down (disabled)
Internet address is 1.1.1.1/16
router(config-if)# description WAN link to Miami
Chapter 6 Review Questions
1. You type show running-config and get this output:
---cut---
line console 0
Exec-timeout 1 44
Password 7 098C0BQR
Login
---cut---
What do the two numbers following the exec-timeout command mean?
minutes and seconds
2. Which connection method for connecting to a router is considered "out-of-band"?
auxiliary
The aux port can be configured to allow a modem to connect to the router.
It lets you dial up to a remote router in order to connect to the aux port if the router is down.
This method is considered "out of band" since its not connecting via "the network"
3. Which two commands are required when configuring SSH on your router?
ip domain-name name
username name password password
Example: Using SSH instead of Telnet
set your hostname, domain, and username
router(config)#
hostname Dallas
Dallas(config)#
ip domain-name Lammle.com
Dallas(config)#
username Michael password 1234
generate encryption keys
Dallas(config)#
crypto key generate rsa genral-keys modulus 1024
The name for the keys will be Michael.Lammle.com
% The key modulus size is 1024 bits
% Generating 1024 bit RSA keys, keys will be non-exportable...[ok]
*June 24 19:25:30.035: %SSH-5-ENABLED: SSH 1.99 has been enabled
enable SSH version 2
router(config)#
ssh version 2
connect to the vty lines of the router
router(config)#
line vty 0 1180
configure SSH and then Telnet as access protocols
router(config-line)#
transport input ssh telnet
4. Which command will show you wheter a DTE or a DCE cable is plugged into serial 0?
show controllers serial 0
will show whether DTE or DCE cable is connected to the interface
NOTE if it is a DTE connection you must add clocking with the
clock rate command
5. Which is a correct combination of file type and default location on a Cisco router?
IOS- flash memory
startup config- NVRAM
running config- RAM
6. You set the console password, but when you display the configuration, the password doesn't show up;
it looks like this:
[output cut]
line console 0
Exec-timeout 1 44
Password 7 098C0BQR
Login
[output cut]
What command would configure the password to be stored this way?
service password-encryption
7. Which command will configure all the default VTY ports on a router?
from global config mode:
line vty 0 4
will set all 5 default lines
8. Which command set the secret password to Cisco?
enable secret Cisco
9. If you wanted to see a message when logging into the router, which command would you use?
MOTD
10. Which prompt indicate that the router is currently in priviliged mode?
router#
11. What command do you type to save the configuration stored in RAM to NVRAM?
copy running-config startup-config
12. You try to telnet into SSFRouter from router to Corp and receive this message:
Corp#telnet SFRouter
Trying SFRouter (10.0.0.1)...Open
Password required, but none set
[Connection to SFRouter closed by foreing host]
Corp#
Which command sequence will address the problem correctly?
SFRouter(config)#
line vty 0 4
SFRouter(config-line)#
password password1234
SFRouter(config-line)#
login
13. Which command will delete the contents of NVRAM on a router?
erase startup-config
14. What is the problem with an interface if you type
show interface serial 9
and receive the following message?
Serial0 is administratively down, line protocol is down
is set to 'shut' by default, fix with no shut
15. Which command displays the configurable parameters and statistics of all interfaces on a router?
show interfaces
16. If you delete the contents of NVRAM and reboot the router, what mode will you be in?
setup mode
--- System Configuration Dialog ---
Would you like to enter the initial configuration dialog? [yes/no]:
17. You type the following command into the router and receive the following output:
Router#show serial 0/0
^
% Invalid input detected at '^' marker.
show interface serial 0/0
18. You type Router#sh ru and receive a % ambiguous command error.
Why did you receive this error?
not specific enough- there is more than one possible
show
command that starts with
ru
19. Which of the following commands will display the current
IP addressing and the layer 1 and 2 status of an interface?
show interfaces
GigabitEthernet0/0/0 is up, line protocol is down (disabled)
Hardware is ISR4331-3x1GE, address is 000d.bd45.db01 (bia 000d.bd45.db01)
Internet address is 1.1.1.1/16
MTU 1500 bytes, BW 1000000 Kbit, DLY 10 usec,
reliability 255/255, txload 1/255, rxload 1/255
Encapsulation ARPA, loopback not set
Keepalive not supported
Half Duplex, 1000Mbps, link type is auto, media type is Auto Select
output flow-control is on, input flow-control is on
ARP type: ARPA, ARP Timeout 04:00:00,
Last input 00:00:08, output 00:00:05, output hang never
Last clearing of "show interface" counters never
Input queue: 0/375/0 (size/max/drops); Total output drops: 0
Queueing strategy: fifo
Output queue :0/40 (size/max)
5 minute input rate 0 bits/sec, 0 packets/sec
5 minute output rate 0 bits/sec, 0 packets/sec
0 packets input, 0 bytes, 0 no buffer
Received 0 broadcasts (0 IP multicasts)
0 runts, 0 giants, 0 throttles
0 input errors, 0 CRC, 0 frame, 0 overrun, 0 ignored
0 watchdog, 1017 multicast, 0 pause input
0 input packets with dribble condition detected
0 packets output, 0 bytes, 0 underruns
0 output errors, 0 collisions, 1 interface resets
0 unknown protocol drops
0 babbles, 0 late collision, 0 deferred
0 lost carrier, 0 no carrier
0 output buffer failures, 0 output buffers swapped out
GigabitEthernet0/0/1 is administratively down, line protocol is down (disabled)
Hardware is ISR4331-3x1GE, address is 000d.bd45.db02 (bia 000d.bd45.db02)
MTU 1500 bytes, BW 1000000 Kbit, DLY 10 usec,
reliability 255/255, txload 1/255, rxload 1/255
Encapsulation ARPA, loopback not set
Keepalive not supported
output flow-control is on, input flow-control is on
ARP type: ARPA, ARP Timeout 04:00:00,
Last input 00:00:08, output 00:00:05, output hang never
Last clearing of "show interface" counters never
Input queue: 0/375/0 (size/max/drops); Total output drops: 0
Queueing strategy: fifo
Output queue :0/40 (size/max)
5 minute input rate 0 bits/sec, 0 packets/sec
5 minute output rate 0 bits/sec, 0 packets/sec
0 packets input, 0 bytes, 0 no buffer
Received 0 broadcasts (0 IP multicasts)
0 runts, 0 giants, 0 throttles
0 input errors, 0 CRC, 0 frame, 0 overrun, 0 ignored
0 watchdog, 1017 multicast, 0 pause input
0 input packets with dribble condition detected
0 packets output, 0 bytes, 0 underruns
0 output errors, 0 collisions, 1 interface resets
0 unknown protocol drops
0 babbles, 0 late collision, 0 deferred
0 lost carrier, 0 no carrier
0 output buffer failures, 0 output buffers swapped out
GigabitEthernet0/0/2 is administratively down, line protocol is down (disabled)
Hardware is ISR4331-3x1GE, address is 000d.bd45.db03 (bia 000d.bd45.db03)
MTU 1500 bytes, BW 1000000 Kbit, DLY 10 usec,
reliability 255/255, txload 1/255, rxload 1/255
Encapsulation ARPA, loopback not set
Keepalive not supported
Half Duplex, 1000Mbps, link type is auto, media type is unknown media type
output flow-control is on, input flow-control is on
ARP type: ARPA, ARP Timeout 04:00:00,
Last input 00:00:08, output 00:00:05, output hang never
Last clearing of "show interface" counters never
Input queue: 0/375/0 (size/max/drops); Total output drops: 0
Queueing strategy: fifo
Output queue :0/40 (size/max)
5 minute input rate 0 bits/sec, 0 packets/sec
5 minute output rate 0 bits/sec, 0 packets/sec
0 packets input, 0 bytes, 0 no buffer
Received 0 broadcasts (0 IP multicasts)
0 runts, 0 giants, 0 throttles
0 input errors, 0 CRC, 0 frame, 0 overrun, 0 ignored
0 watchdog, 1017 multicast, 0 pause input
0 input packets with dribble condition detected
0 packets output, 0 bytes, 0 underruns
0 output errors, 0 collisions, 1 interface resets
0 unknown protocol drops
0 babbles, 0 late collision, 0 deferred
0 lost carrier, 0 no carrier
0 output buffer failures, 0 output buffers swapped out
Vlan1 is administratively down, line protocol is down
Hardware is CPU Interface, address is 00d0.9715.9967 (bia 00d0.9715.9967)
MTU 1500 bytes, BW 100000 Kbit, DLY 1000000 usec,
reliability 255/255, txload 1/255, rxload 1/255
Encapsulation ARPA, loopback not set
ARP type: ARPA, ARP Timeout 04:00:00
Last input 21:40:21, output never, output hang never
Last clearing of "show interface" counters never
Input queue: 0/75/0/0 (size/max/drops/flushes); Total output drops: 0
Queueing strategy: fifo
Output queue: 0/40 (size/max)
5 minute input rate 0 bits/sec, 0 packets/sec
5 minute output rate 0 bits/sec, 0 packets/sec
1682 packets input, 530955 bytes, 0 no buffer
Received 0 broadcasts (0 IP multicast)
0 runts, 0 giants, 0 throttles
0 input errors, 0 CRC, 0 frame, 0 overrun, 0 ignored
563859 packets output, 0 bytes, 0 underruns
0 output errors, 23 interface resets
0 output buffer failures, 0 output buffers swapped out
show ip interface
GigabitEthernet0/0/0 is up, line protocol is down (disabled)
Internet address is 1.1.1.1/16
Broadcast address is 255.255.255.255
Address determined by setup command
MTU is 1500 bytes
Helper address is not set
Directed broadcast forwarding is disabled
Outgoing access list is not set
Inbound access list is not set
Proxy ARP is enabled
Security level is default
Split horizon is enabled
ICMP redirects are always sent
ICMP unreachables are always sent
ICMP mask replies are never sent
IP fast switching is disabled
IP fast switching on the same interface is disabled
IP Flow switching is disabled
IP Fast switching turbo vector
IP multicast fast switching is disabled
IP multicast distributed fast switching is disabled
Router Discovery is disabled
IP output packet accounting is disabled
IP access violation accounting is disabled
TCP/IP header compression is disabled
RTP/IP header compression is disabled
Probe proxy name replies are disabled
Policy routing is disabled
Network address translation is disabled
BGP Policy Mapping is disabled
Input features: MCI Check
WCCP Redirect outbound is disabled
WCCP Redirect inbound is disabled
WCCP Redirect exclude is disabled
GigabitEthernet0/0/1 is administratively down, line protocol is down (disabled)
Internet protocol processing disabled
GigabitEthernet0/0/2 is administratively down, line protocol is down (disabled)
Internet protocol processing disabled
Vlan1 is administratively down, line protocol is down
Internet protocol processing disabled
20. At which layer of the OSI model would you assume the problem is if you type
show interface serial 1
and receive the following message?
Serial 1 is down, line protocol is down
physical
if you see both interface and protocal down, it's physical
if you see serial1 is up but line protocol down, its data link- data-link keepalives are not being sent from the remote end
END CHAPTER 6
15 hours 1-15 thru 1-19-22
original total hours 63
2.5 hours review 12-21-22
review total hours 13.5
book page 274/822
Chapter 7 Notes - Managing a Cisco Internetwork
notes
Configuration Register
16 bits / 2 bytes... bit values from 15 to 0
uses Hexadecimal nibbles
Chapter 7 Exam Essentials - Managing a Cisco Internetwork
1. Define the Cisco router componenets
ROM
- used to start and maintain the router. Holds bootstrap, POST, mini-IOS
bootstrap
- stored in the microcode of the ROM. Finds where the IOS program is located and loads the file.
POST
- stored in the microcode of the ROM. Used to check the basic funtionality and determine which interfaces are present
ROM monitor
- stored in the microcode of the ROM. Used for manufacturing, testing, and troubleshooting
mini-IOS
- Called the RXBOOT or 'bootloader'. It's a small OS in ROM that can be used to bring up an interface and load a Cisco IOS into flash memory
-----------------------------------------------------------------------------------------------------------------------
flash memory
- EEPROM- default location of the IOS
NVRAM
-holds the router/switch configuration
not erased when the device is reloaded
configuration register
- controls how the router boots up
Tells the router to load the IOS from flash memory as well as to load the configuration from NVRAM
RAM
- used to hold packet buffers, ARP cache, routing tables and the data structures that allow the router to function.
running-config is stored in RAM
routers expand the IOS from flash into RAM at boot
2. Identify the steps in the router boot sequence
POST
bootstrap
load the IOS from flash into RAM
load the configuration file from NVRAM into RAM
running-config and the IOS are both now running in RAM
3. Understand configuration register commands and settings
0x2102 default- find the boot sequence in NVRAM
0x2101 boot from ROM
0x2142 do not load the startup-config in NVRAM. Used for password recovery
4.Perform password recovery
NOTE - this requires physical access to reboot the router
The default configuration register value is 0x2102 which tells the router to load a config stored
in NVRAM(startup-config).
To recover a password, we need to change the config register value to 0x2142 which tells the router to ignore the VRAM contents and load a 'non configured' OS.
"configurations" can be defined as any changes we make to the device: hostname, passwords, interfaces, etc
For this demo, our 4331 router is configured with the hostname 4331 and the password 1234
4331(config)#
enable secret 1234
4331#
copy run start
Destination filename [startup-config]?
Building configuration...
[OK]
Step 1. Bounce the router, then interrupt the boot sequence by performing a break.
Initializing Hardware ...
Checking for PCIe device presence...done
System integrity status: 0x610
Rom image verified correctly
System Bootstrap, Version 16.7(3r), RELEASE SOFTWARE
Copyright (c) 1994-2018 by cisco Systems, Inc.
Current image running: Boot ROM0
Last reset cause: LocalSoft
Cisco ISR4331/K9 platform with 4194304 Kbytes of main memory
no valid BOOT image found
Final autoboot attempt from default boot device...
Located isr4300-universalk9.16.06.04.SPA.bin
###############################################################
CTRL+BREAK
monitor: command "boot" aborted due to user interrupt
rommon 1 >
Step 2. We're given a ROM MONITOR prompt which allows us to change the configuration register (Cisco ISR/2600 Series commands).
rommon 1 >
confreg 0x2142
rommon 1 >
reset must reset or power cycle router to apply the change
system will ask if you want Setup Mode - that is the the generic startup message,
since we are bypassing the startup configuration. Our answer is no.--- System Configuration Dialog ---
Would you like to enter the initial configuration dialog? [yes/no]:
N + Enter
we now have full access to this non-configured OS. We can enter priviliged mode with no password.
Router>
enable
Router#
show version
Cisco IOS Software [Everest], ISR Software (X86_64_LINUX_IOSD-UNIVERSALK9-M), Version 16.6.4,RELEASE SOFTWARE (fc3)
[cut]
Configuration register is 0x2142
this verifies that our configs are not in use (no hostname in the prompt) and our config register has been changed to 2142
HERE IS THE KEY-
we are going to restore the configuration by copying the "startup-config"
into our live environment AKA the "running-config"
Router#
copy startup-config running-config
Destination filename [running-config]? Enter
695 bytes copied in 0.416 secs (1670 bytes/sec)
4331#
%SYS-5-CONFIG_I: Configured from console by console
we get our old prompt back:
4331#
Note that we DO NOT know the password required to enter privliged mode that we are currently inside of!
if you exit this prompt back out to user mode, you will not be able to get back in without the password.
We entered privileged mode from within the generic configuration. Then inserted our saved configuration 'beneath' our prompt.
This action does not kick you out of priv. mode, which will allow us to RESET the password for our saved configuration.
set the new password
4331(config)#
enable secret 0000
set the config register back to default, to point back to NVRAM on the next reboot
(you can do this from global config mode as well as rommon mode)
4331(config)#
config-register 0x2102
4331#
show version
[cut]
Configuration register is 0x2142 (will be 0x2102 at next reload)
now we can save the config with the updated password.
Two ways to do it-
4331#
write
Building configuration...
[OK]
OR
4331#
copy running-config startup-config
Destination filename [startup-config]?
Building configuration...
[OK]
reload the router and your new password will be saved into your config
4331#
reload
this feature is helpful since Cisco equipment tends to run for long stretches of time (years) and the passwords get forgotten.
Thank you to Jeremy Cioara for help on this topic
5. Back up an IOS image
we can copy a router's configuration to a TFTP server with either of these commands:
Router#
copy running-config tftp
Router#
copy startup-config tftp
to verify either of the configs before backup, we can use these commands:
Router#
show running-config
Router#
show startup-config
6. Restore or upgrade an IOS image - note we are talking about the IOS itself, not the 'configuration'
We will download the IOS file from TFTP server to flash memory on the router. Command requires the IP of the TFTP host and the filename
Before we begin we must make sure the IOS file is in the default TFTP directory on the host.
The command will not ask you where the file is on the host....
Router#
copy tftp flash
Address or name of remote host []? 1.1.1.2
Source filename []? c2800nm-advsecurityk9-mz.124.12.bin
Destination filename[c2800nm-advsecurityk9-mz.124.12.bin]? ENTER
%Warning this is a file already existing with this name
Do you want to over write [confirm] ENTER
Accessing tftp://1.1.1.2/c2800nm-advsecurityk9-mz.124-12.bin...
Loading c2800nm-advsecurityk9-mz.124-12.bin from 1.1.1.2 (via FastEthernet0/0): !!!!!!!!!!!!!!!!
!!!!!!!!!!!!!!!!!!!!!!!!!!
[OK - 21710744 bytes]
21710744 bytes copied in 82.880 secs (261954 bytes/sec)
Router#
to restore configuration:
restore from startup-config:
Router#
copy startup-config running-config
or we can restore from a backup on TFTP server
Router#
copy tftp running-config
Address or name of remote host []? 1.1.1.2
Source filename []? todd-confg
Destination filename[running-config?] ENTER
Accessing tftp://1.1.1.2/todd-confg...
Loading todd-confg from 1.1.12 (civa FastEthernet0/0): !
[OK - 776 bytes]
776 bytes copied in 9.212 secs (84 bytes/sec)
Router#
*Jan 23 12:40:00.000: %SYS-5-CONFIG_I: Configured from tftp://1.1.1.2/todd-confg by console
Router#
7. Describe best practices to prepare to back up an IOS image to a network server
Ensure you can acccess the network server, and there is adequate storage space.
Verify the file naming and path requirements
have the source IOS file in the default TFTP directory
8. Save the configuration of a router
Router#
copy running-config startup-config
9. Erase the configuration of a router
Router#
erase startup-config
10. Understand and use the Cisco IFS file system management commands
IFS = IOS File System
UNIX Based
dir
show files in a directory. Requires privliged mode. If not path is given as argument, you'll see the directory of 'flash' root.
NOTE the file paths use a URL format
R1#
dir
Directory of flash:/
3 -rw- 486899872 <no date> isr4300-universalk9.16.06.04.SPA.bin
2 -rw- 28282 <no date> sigdef-category.xml
1 -rw- 227537 <no date> sigdef-default.xml
3249049600 bytes total (2761893909 bytes free)
-------------------------------------------------------------------------------------------------------
copy
often used to backup, restore, or ugprade the IOS
first arg = source
second arg = destination
R1#
copy
source
destination
-------------------------------------------------------------------------------------------------------
more
display a text file
-------------------------------------------------------------------------------------------------------
show file
display a text file
-------------------------------------------------------------------------------------------------------
delete
remote file (may also need to use SQUEEZE to free up the space)
-------------------------------------------------------------------------------------------------------
erase/format
may delete flash drive depending on system
-------------------------------------------------------------------------------------------------------
cd/pwd
change directory / print working directory
-------------------------------------------------------------------------------------------------------
mkdir/rmdir
create / delete directories
11. Describe the value of CDP
Cisco Discovery Protocol - helps to document / troubleshoot the network
See lab 7.4
12. List the information provided by the output of
show cdp neighbors
device ID
local interface
holdtime
capabilility
platform
port ID (remote interface)
13. Understand how to establish a Telnet session with multiple routers simultaneously
Press Ctrl+Shift+6 then x to exit a telnet session without closing it
14. Identify current Telnet sessions
R1#
show sessions
15. Build a static host table on a router
R1#
ip host
host_name
ip_address
manually assigning an IP to a host name. You can apply multiple IP's to one host entry
see lab 7.6
16. Verify the host table on a router
R1#
show hosts
17. Describe the function of the ping command
Packet Internet Groper uses ICMP echo requests and replies to verify an active IP address on a network
18. Ping a vaild host ID from the correct prompt
R1#
ping 1.1.1.1
Note PING works from user or privliged mode but NOT config mode
Chapter 7 Written Lab 7.1 - IOS Management
TFTP Server Setup - network layout is not from book- I created this network to help demo the written lab
TFTP server is already created and switched on by default within the 'Server' object
Router Configuration
R1(config)#
int g0/0/1
R1(config-if)#
ip address 10.1.1.4 255.255.255.0
R1(config-if)#
no shutdown
%LINK-5-CHANGED: Interface GigabitEthernet0/0/1, changed state to up
%LINEPROTO-5-UPDOWN: Line protocol on Interface GigabitEthernet0/0/1, changed state to up
r1(config-if)#
do show ip int brief
Interface IP-Address OK? Method Status Protocol
GigabitEthernet0/0/0 unassigned YES manual administratively down down
GigabitEthernet0/0/1 192.1.1.4 YES NVRAM up up
GigabitEthernet0/0/2 unassigned YES NVRAM administratively down down
Vlan1 unassigned YES NVRAM administratively down down
Switch Configuration
SW1(config)#
int f0/1
SW1(config-if)#
no shutdown
%LINK-5-CHANGED: Interface FastEthernet0/1, changed state to up
%LINEPROTO-5-UPDOWN: Line protocol on Interface FastEthernet0/1, changed state to up
SW1(config-if)#
int f0/2
SW1(config-if)#
no shutdown
%LINK-5-CHANGED: Interface FastEthernet0/2, changed state to up
%LINEPROTO-5-UPDOWN: Line protocol on Interface FastEthernet0/2, changed state to up
Test connectivity to the server
R1#
ping 192.1.1.3
Type escape sequence to abort.
Sending 5, 100-byte ICMP Echos to 192.1.1.3, timeout is 2 seconds:
.!!!!
Success rate is 80 percent (4/5), round-trip min/avg/max = 0/1/6 ms
Find the name of the Router flash file
R1#
show flash
System flash directory:
File Length Name/status
3 486899872isr4300-universalk9.16.06.04.SPA.bin
2 28282 sigdef-category.xml
1 227537 sigdef-default.xml
[487155691 bytes used, 2761893909 available, 3249049600 total]
3.17338e+06K bytes of processor board System flash (Read/Write)
we need to paste that filename into our copy command below
1. command to copy a Cisco IOS to a TFTP server?
R1#
copy flash tftp
Source filename []? isr4300-universalk9.16.06.04.SPA.bin
Address or name of remote host []? 192.1.1.3
Destination filename [isr4300-universalk9.16.06.04.SPA.bin]? ENTER
Writing isr4300-universalk9.16.06.04.SPA.bin...!!!!!!!!!!!!!!!!
!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!
[OK - 486899872 bytes]
486899872 bytes copied in 12.364 secs (126865 bytes/sec)
the file appears on our server
2. command to copy a Cisco startup-config file to a TFTP server?
R1#
copy running-config tftp
Address or name of remote host []? 192.1.1.3
Destination filename [r1-confg]? ENTER
Writing running-config.....!!
[OK - 707 bytes]
707 bytes copied in 3 secs (235 bytes/sec)
the file appears on our server
OR
R1#
copy startup-config tftp
3. command to copy the startup-config file to DRAM?
R1#
copy startup-config running-config
the running configuration exists in DRAM
4. What is an older command that you can use to copy the startup-config file to DRAM?
R1#
config mem
(not supported by packet tracer)
5. What command can you use to see the neighbor router's IP address from your router prompt?
R1#
show cdp neighbor detail
OR
R1#
show cdp entry *
6. What command to see the hostname, local interface, platform, and remote port of a neighbor router?
R1#
show cdp neighbor
7. What keystrokes can you use to telnet into multiple devices simultaneously?
Ctrl + Shift + 6, then X
8. What command will show you your active Telnet connections to neighbor and remote devices?
R1#
show sessions
9. What command can you use to upgrade a Cisco IOS?
R1#
copy tftp flash
10. What command can you use to merge a backup configuration with the configuration in RAM?
R1#
copy tftp run
OR
R1#
copy start run
RAM = running configuration
Chapter 7 Written Lab 7.2 - Router Memory
Identify the location in a router where each of the files is stored by default:
1. Cisco IOS
flash
2. Bootstrap
ROM
3. Startup configuration
NVRAM
4. POST
ROM
5. Running configuration
RAM
6. ARP cache
RAM
7. Mini IOS
ROM
8. ROM Monitor
ROM
9. Routing tables
RAM
10. packet buffers
RAM
****dont make the mistake of thinking arp cache, routing tables, packet buffers, are stored somewhere other than RAM
they are considered part of running-config which exists in RAM
Chapter 7 Hands-on Labs
To complete these labs, we are going to need three routers and one TFTP server.
Here is the topology:
Server Configuration
ipv4 address: 193.1.1.2
subnet mask: 255.255.255.248
default gateway: 193.1.1.1
Switch Configuration
SW1#
interface range f0/1-2
SW1(config-if-range)#
no shut
Router Configurations
R1(config)#
int g0/0/0
R1(config)#
ip addr 193.1.1.9 255.255.255.248
R1(config)#
no shut
R1(config)#
int g0/0/1
R1(config)#
ip addr 193.1.1.1 255.255.255.248
R1(config)#
no shut
the server's default gateway
R2(config)#
int g0/0/0
R2(config)#
ip addr 193.1.1.10 255.255.255.248
R2(config)#
no shut
R2(config)#
int g0/0/1
R2(config)#
ip addr 193.1.1.17 255.255.255.248
R2(config)#
no shut
R3(config)#
int g0/0/0
R3(config)#
ip addr 193.1.1.18 255.255.255.248
R3(config)#
no shut
the segment between R1 and the server
network 193.1.1.0/29
block of 8
hosts .1, .2
the segment between R1 and R2
network 193.1.1.8/29
block of 8
hosts .9 , .10
the segment between the R2 and R3
network 193.1.1.16/29
block of 8
hosts .17 , .18
THIS IS INCORRECT!!!!
I have misunderstood the instructions.
the problem with this topology is that packets cannot pass through the routers. We dont have any ROUTING setup. ROUTING is covered in the next chapter.
For these labs, we dont need routing, but we need multiple routers to demo telnet and CDP. Here are the instructions:
my mistake was not putting all router interfaces in the same subnet. I tried to do this initially, but it wouldnt work because I had the routers linked together rather than connected by a switch.
The instructions say:
"Your PC and the router(s) are connected together with a switch"
this is the part I missed. The pc and all router interfaces should be on the same switch and the same network
Here is the corrected topology
Server Configuration
ipv4 address: 193.1.1.4
subnet mask: 255.255.255.248
default gateway: 193.1.1.1
Switch Configuration
SW1#
interface range f0/1-4
SW1(config-if-range)#
no shut
Router Configurations
R1(config)#
int g0/0/0
R1(config)#
ip addr 193.1.1.1 255.255.255.248
R1(config)#
no shut
the server's default gateway
R2(config)#
int g0/0/0
R2(config)#
ip addr 193.1.1.2 255.255.255.248
R2(config)#
no shut
R3(config)#
int g0/0/0
R3(config)#
ip addr 193.1.1.3 255.255.255.248
R3(config)#
no shut
Chapter 7 Hands-on Lab 7.1 Backing up your router IOS
1. verify connection to the server
R1#
ping 193.1.1.1
Type escape sequence to abort.
Sending 5, 100-byte ICMP Echos to 193.1.1.2, timeout is 2 seconds:
.!!!!
Success rate is 80 percent (4/5), round-trip min/avg/max = 0/1/5 ms
2. show contents of flash memory
R1#
show flash
System flash directory:
File Length Name/status
3 486899872isr4300-universalk9.16.06.04.SPA.bin
2 28282 sigdef-category.xml
1 227537 sigdef-default.xml
[487155691 bytes used, 2761893909 available, 3249049600 total]
3.17338e+06K bytes of processor board System flash (Read/Write)
show flash gives ALL of the files in flash memory
show version gives the current running file
3. show the IOS currently running
R1#
show version
Cisco IOS XE Software, Version 03.16.05.S - Extended Support Release
[cut]
ROM: IOS-XE ROMMON
Router uptime is 9 minutes, 39 seconds
Uptime for this control processor is 9 minutes, 39 seconds
System returned to ROM by power-on
System image file is "bootflash:/isr4300-universalk9.03.16.05.S.155-3.S5-ext.SPA.bin"
Last reload reason: PowerOn
[cut]
note that the file that is currently running is NOT located in the flash storage!!!
4. backup IOS from router to server
R1#
copy flash tftp
Source filename []?isr4300-universalk9.16.06.04.SPA.bin
Address or name of remote host []? 193.1.1.4
Destination filename [isr4300-universalk9.16.06.04.SPA.bin]? ENTER
Writing isr4300-universalk9.16.06.04.SPA.bin...!!!!!!!!!!!!!!!
[OK - 486899872 bytes]
486899872 bytes copied in 12.526 secs (125224 bytes/sec)
Chapter 7 Hands-on Lab 7.2 Upgrading or restoring your router IOS
1. verify connection to the server
R1#
ping 193.1.1.4
Type escape sequence to abort.
Sending 5, 100-byte ICMP Echos to 193.1.1.2, timeout is 2 seconds:
!!!!!
Success rate is 100 percent (5/5), round-trip min/avg/max = 0/0/1 ms
2. copy from tftp sever to flash
R1#
copy tftp flash TFTP comes first in the command since we are pulling from TFTP server.
In this command, remot host address is required before file name
Address or name of remote host []? 193.1.1.4
Source filename []?isr4300-universalk9.16.06.04.SPA.bin
Destination filename [isr4300-universalk9.16.06.04.SPA.bin]? ENTER
%Warning:There is a file already existing with this name
Do you want to over write? [confirm]
Accessing tftp://193.1.1.4/isr4300-universalk9.16.06.04.SPA-12-23-22...
Loading isr4300-universalk9.16.06.04.SPA-12-23-22.bin from 193.1.1.4: !!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!
[OK - 486899872 bytes]
486899872 bytes copied in 12.785 secs (122688 bytes/sec)
Chapter 7 Hands-on Lab 7.3 Backing up the router configuration
1. verify connection to the server
R1#
ping 193.1.1.2
Type escape sequence to abort.
Sending 5, 100-byte ICMP Echos to 193.1.1.4, timeout is 2 seconds:
!!!!!
Success rate is 100 percent (5/5), round-trip min/avg/max = 0/0/1 ms
2. copy running-confing to server
R1#
copy run tftp
Address or name of remote host []? 193.1.1.4
Destination filename [R1-confg]?ENTER "R1-confg" is the default name
Writing running-config...!!
[OK - 668 bytes]
668 bytes copied in 0.004 secs (167000 bytes/sec)
Chapter 7 Hands-on Lab 7.4 Using the Cisco Discovery Protocol (CDP)
R1#
show cdp
Global CDP information:
Sending CDP packets every 60 seconds
Sending a holdtime value of 180 seconds
Sending CDPv2 advertisements is enabled
R1#
show cdp interface
Vlan1 is administratively down, line protocol is down
Sending CDP packets every 60 seconds
Holdtime is 180 seconds
GigabitEthernet0/0/0 is up, line protocol is up
Sending CDP packets every 60 seconds
Holdtime is 180 seconds
GigabitEthernet0/0/1 is administratively down, line protocol is down
Sending CDP packets every 60 seconds
Holdtime is 180 seconds
GigabitEthernet0/0/2 is administratively down, line protocol is down
Sending CDP packets every 60 seconds
Holdtime is 180 seconds
R1#
show cdp entry *
Device ID: SW1
Entry address(es):
Platform: cisco 2960, Capabilities: Switch
Interface: GigabitEthernet0/0/0, Port ID (outgoing port): FastEthernet0/1
NOTE g0/0/0 is the outgoing port on this router, F0/1 is the port on the switch at other end
Holdtime: 157
Version :
Cisco IOS Software, C2960 Software (C2960-LANBASEK9-M), Version 15.0(2)SE4, RELEASE SOFTWARE (fc1)
Technical Support: http://www.cisco.com/techsupport
Copyright (c) 1986-2013 by Cisco Systems, Inc.
Compiled Wed 26-Jun-13 02:49 by mnguyen
advertisement version: 2
Duplex: full
R1#
show cdp entry neighbors
[no output]
R1#
show cdp neighbors detail
Device ID: SW1
Entry address(es):
Platform: cisco 2960, Capabilities: Switch
Interface: GigabitEthernet0/0/0, Port ID (outgoing port): FastEthernet0/1
Holdtime: 178
Version :
Cisco IOS Software, C2960 Software (C2960-LANBASEK9-M), Version 15.0(2)SE4, RELEASE SOFTWARE (fc1)
Technical Support: http://www.cisco.com/techsupport
Copyright (c) 1986-2013 by Cisco Systems, Inc.
Compiled Wed 26-Jun-13 02:49 by mnguyen
advertisement version: 2
Duplex: full
Chapter 7 Hands-on Lab 7.5 Using Telnet
enable telnet on R2 and set password
R2(config)#
line vty 0 15
R2(config-line)#
password telnet
R2(config-line)#
login
enable telnet on R3 and set password
R3(config)#
line vty 0 15
R3(config-line)#
password telnet
R3(config-line)#
login
note that the result of this command on each router, by default,
is to present all 15 lines in TWO SEPERATE chunks: 0-4 and 5-15
R3#
show run
[cut]
!
!
!
line con 0
!
line aux 0
!
line vty 0 4
password telnet
login
line vty 5 15
password telnet
login
!
!
!
end
--------------------------------------------------------------------------------
connect to R2 from R1
R1#
telnet 193.1.1.2
Trying 193.1.1..2 ...Open
User Access Verification
Password: telnet
prompt changes to R2 to indicate we are remoted in
R2>
exit the session
ctrl + shift + 6, x
prompt changes back to R1
R1#
--------------------------------------------------------------------------------
connect to R3 from R1
R1#
193.1.1.3 note that the word 'telnet' is not required bc we are still in telnet mode
Trying 193.1.1..3 ...Open
User Access Verification
Password: telnet
prompt changes to R3 to indicate we are remoted in
R3>
exit the session
ctrl + shift + 6, x
prompt changes back to R1
R1#
--------------------------------------------------------------------------------
We have exited the sessions, but they are still open
R1#
show sessions
Conn Host Address Byte Idle Conn Name
1 193.1.1.2 193.1.1.2 0 0 193.1.1.2
* 2 193.1.1.3 193.1.1.3 0 0 193.1.1.3
two telnet sessions- notice that the 'conn number' doesnt correspond to ip address in any way.
R1#
show users
Line User Host(s) Idle Location
* 0 con 0 193.1.1.2 00:00:03
193.1.1.3 00:00:43
this is saying one user is on this router, with two outbound connections (but it isnt showing that they are vty connections)
... they must both be considered 'console' connections outbound and are not considered 'vty' until they are received inbound
the asterisk means something different here than above... doesnt mean default(most recent)session... what does it mean?
back to R2
R2#
show users
Line User Host(s) Idle Location
* 4 vty 0 idle 00:00:00 193.1.1.1
Interface User Mode Idle Peer Address
this is saying that there is one (unnamed) user remoted in via line vty 4
back to R3
R3#
show users
Line User Host(s) Idle Location
* 4 vty 0 idle 00:00:00 193.1.1.1
Interface User Mode Idle Peer Address
this is saying that there is one (unnamed) user remoted in via line vty 4
-------------------------------------------------------------------------------------
Important Considerations:
-
asterisk indicates default session
-
when telnetting in, you will be in user mode. If there is no password already set for PRIVILEGED MODE, you will be unable to enter
-
be careful with 'exit'. it will exit the telnet session if you exit at priv. mode. Use 'disable' to leave priv mode.
-
after 'suspending' a session with ctrl+shift+6,x and youre back at your original priv. prompt, do not press enter to create line breaks-
rather than break lines as usual, the keystroke will cause this:
[Resuming connection 1 to 193.1.1.2 ... ]
prompt will sit here until you strike enter again, then you'll return to that session. What is actually happening is that
youre connecting to the 'default' telnet connection. The same behavior happens when youre at the 'show sessions' screen.
Even if you are not viewing active sessions, the enter key(twice) will connect you to the default session
-
you can use disconnect or exit to end a session
-
Ex: disconnect 1 at the show sessions screen
Chapter 7 Hands-on Lab 7.6 Resolving Hostnames
We're going to build a host table on R1 so we can connect to the other routers via hostname rather than type in the IP address
the command is ip host name arg ip arg
R1(config)#
ip host R2 193.1.1.2
R1(config)#
ip host R3 193.1.1.3
Now if we enter R2 or telnet R2 we get the telnet prompt
R1# R2
Trying 193.1.1.2 ...Open
User Access Verification
Password:
same for the PING command
R1# ping R2
Type escape sequence to abort.
Sending 5, 100-byte ICMP Echos to 193.1.1.2, timeout is 2 seconds:
!!!!!
Success rate is 100 percent (5/5), round-trip min/avg/max = 0/0/2 ms
R1#
show hosts
Default Domain is not set
Name/address lookup uses domain service
Name servers are 255.255.255.255
Codes: UN - unknown, EX - expired, OK - OK, ?? - revalidate
temp - temporary, perm - permanent
NA - Not Applicable None - Not defined
Host Port Flags Age Type Address(es)
R2 None (perm, OK) 0 IP 193.1.1.2
R3 None (perm, OK) 0 IP 193.1.1.3
R1#
telnet R2
R2>
CTRL + SHIFT + 6, X
R1#
telnet R3
R3>
CTRL + SHIFT + 6, X
R1#
show session
Conn Host Address Byte Idle Conn Name
1 R2 193.1.1.2 0 0 R2
* 2 R3 193.1.1.3 0 0 R3
Chapter 7 Review Questions
1. What does the command
confreg 0x2142
provide?
bypass startup-config, to allow password reset
2. Which command will copy the IOS to a backup host on your network?
copy flash tftp
3. You are troubleshooting a connectivity problem in your corporate network and want to isolate the problem. You suspect that a router on the route to an unreachable
network is at fault. What IOS user exec command should you issue?
traceroute
note this is not a priviliged mode command; it can be run from user mode
4. You copy a configuration from a network host to a router's RAM. The configuration looks correct, yet it is no working at all. What could the problem be?
when you perform a copy from a network host to a router, the interfaces are automatically shut down and have to be manually enabled with no shutdown
5. A network administrator wants to upgrade the IOS of a router without removing the image currently installed. What command will display the amount of memory consumed by the
current IOS image and indicate whether there is enough room available to hold both the current and new images?
show flash
6. The corporate office sends you a new router to connect, but upon connecting the console cable, you see that there is already a configuration on the router.
What should be done before a new configuration is entered in the router?
erase NVRAM and restart the router
erase startup-config
reload
7. Which command loads a new version of the Cisco IOS into a router?
copy tftp flash
8. Which command will show you the IOS version running on your router?
show version
9. What should the configuration register value be after you successfully complete the password recovery procedure and return the router to normal operation?
0x2102
10. You save the configuration on a router with the
copy running-config startup-config
command and reboot the router. The router, however, comes up with a blank configuration. What can the problem be?
wrong config register causing you to bypass startup-confing in NVRAM
11. If you want to have more than one Telnet session open at the same time, what keystroke combination would you use?
CTRL+SHIFT+6, X
12. You are unsuccessful in telnetting into a remote device, but you could telnet to the router earlier, However, you can still ping the remote device.
What can the problem be?
access control list could be filtering telnet
OR
the VTY password may not be set on the target
13. What information is displayed by the
show hosts
command?
gives info on temporary DNS entries and permanent name-to-address mappings created using the ip host command
14. Name three commands that can be used to check LAN connectivity problems on a router?
trace
show interfaces
show ip route
15. You telnet to a router and make your necessary changes; now you want to end the Telnet session. What command do you type in?
exit
16. You telnet into a remote device and type
debug ip rip
but no output from the
debug
command is seen. What could the problem be?
to see console messages through a telnet session, you must enter the command terminal monitor
17. Which command displays the configuration register setting?
show version
18. You need to gather the IP address of a remote switch that is located in Hawaii. What can you do to find the address?
show cdp neighbors detail
19. You have your laptop directly connected into a router's Ethernet port. Which are requirements for the
copy flash tftp
command to be successful?
have a TFTP server running on the laptop
laptop must have an IP on the same subnet as the router interface
give the IP address of the laptop when asked after entering the command
20. The configuration register setting of 0x2102 provides what function to a router?
points to NVRAM for startup-configuration AND boot sequence
END CHAPTER 7
26 hours 1-19 thru 1-26-22
original total hours 89
7 hours review 12-23-22
review total hours 20.5
book page 344/822
avg 15 min/page (reading and exercises/labs)
Chapter 8 Exercises
pg 374
before I begin to configure this network, I want to look closer at the HARDWARE
Todd mentions these routers:
2811 with four serial interfaces and switch module or wireless card
1841
while the book was published in 2011, both routers appear to be available in 2021 packet tracer,
but both are considered legacy as of Feb 2022.
The 2811:
The 1841:
we're going to need to understand the MODULES. What are these?
a few examples:
NM-1E is a 1-port ethernet module
NM-1FE-TX is a fast ethernet module
NM-8A/s is an Eight Port Async/Sync Network Module
HWIC-2T is a 2-port serial WAN interface card
HWIC-AP-AG-B is a wireless card
What is an "NM module"?
A network module is a software module that implements a specific
function in a network stack, such as a data link interface, a transport protocol,
or a network application.
What is a "HWIC module"?
A high-speed WAN interface card
Here is a look inside a real 2811:
Back to the requirements for our lab- Todd says the 2811 'Corp' router needs a switch module
and four serial interfaces. NOTE the book doesnt give specifics on how to create the topology in Packet Tracer.
Our Packet Tracer 2811 offers these modules:
The NM-ESW-16 appears to be the only 'switch module', so I will add that.
And the HWIC-2T is a 2-Port Serial High-Speed WAN Interface Card, providing 2 serial ports.
I will add two of these.
next: R3, which needs to be a 2811 with a wirless card. I will add the HWIC-AP-AG-B:
The HWIC-AP-AG-B module is a High-Speed WAN Interface Card providing integrated Access Point
functionality in the Cisco 1800 (Modular), Cisco 2800,
and Cisco 3800 Integrated Services Routers.
It supports Single Band 802.11b/g or Dual Band 802.11a/b/g radios.
our router hardware is in place:
and here is where we need to end up
Next we need to figure out how to connect the server farm to the switch card on R1:
if I use the auto-select cable, I get a copper crossover cable connecting at fa0/0 on the router.
Per the diagram fa0/0 should
connect to R3. I need to connect the servers to the switch card on R1.
Instead of using the auto-select cable, I'll try a straight-through cable.
Success. While the auto-select cable did not give me an option as to what port it will connect to, I did get the option when
manually applying the straight-through cable. Instead of connecting to F0/0 which would require a crossover-cable(computer to router),
I will connect to the integrated switch at port F1/0, then connect the other two servers to F1/1 and F1/2, respectively.
Also worth noting: the Physical Device diagrams in Packet Tracer do not show cables plugged into the ports.
We are relying on the labels on the logical diagram to see which cables are plugged into which ports...
As far as how we can tell what is connected from within the CLI.. I dont know right now.
Now I will connect the other routers. Here is the chart specifiying what interfaces should be used:
Router
Network Address
Interface
Address
CORP
10.1.1.0
Vlan1 (switch card)
10.1.1.1
10.1.2.0
S0/0/0
10.1.2.1
10.1.3.0
S0/0/1 (DCE)
10.1.3.1
10.1.4.0
S0/1/0
10.1.4.1
10.1.5.0
F0/0
10.1.5.1
R1
10.1.2.0
S0/0/0 (DCE)
10.1.2.2
10.1.3.0
S0/0/1
10.1.3.2
192.168.10.0
F0/0
192.168.10.1
192.168.20.0
F0/1
192.168.20.1
R2
10.1.4.0
S0/0/0 (DCE)
10.1.4.2
192.168.30.0
F0/0
192.168.30.1
192.168.40.0
F0/0
192.168.40.1
R3
10.1.5.0
F0/0
10.1.5.2
172.16.10.0
Dot11Radio0/0/0
172.16.10.1
PROBLEM
The R1 router doesnt appear to have any serial interfaces
I will add an HWIC-2T card to both R1 and R2 since the diagram calls for serial interfaces.
The HWIC-2T is a Cisco 2-Port Serial High-Speed WAN Interface Card, providing 2 serial ports.
PROBLEM
The Corp router is not showing the expected available interfaces. I need to connect R1 to the S0/0/0 interface on Corp and R2 to the S0/0/1 interface on Corp.
My Corp router is not showing those interfaces:
Solution
the placement of the cards on the router determines which interface numbers will be available.
In this case, it seems the interfaces start from the bottom right corner and increase on each slot moving clockwise. I found this out by filling all four slots on my router
which led to all interfaces being available. I then ran a card in each slot individually to isolate which interface numbers correspond to each slot:
Interestingly, while the physical slots seem to follow a 'clockwise' pattern, the list of available slots in the logical diagram does not;
We get an output of interfaces corresponding to slot 2, then 3, 1, and 4. This is a 'bottom to top' then 'left to right' pattern. Tricky.
Having said all that... I will run cards in slots 1 and 2 for this lab since we only need interfaces S0/0/0, S0/0/1, S0/1/0
The Router topology:
I'm not clear on the connections from R1 and R2 to the clients.. I assume there are switches involved.
For now I will follow the next steps in the book which
are to configure the corp router as follows:
Router(config)#
hostname Corp
Corp(config)#
enable secret todd
Corp(config)#
interface vlan 1
Corp(config-if)#
description Switch Card to Core Network
Corp(config-if)#
ip address 10.1.1.1 255.255.255.0
Corp(config-if)#
no shut
----------------------------------------------------------------------------------------------------------------
Corp(config-if)#
int f1/0
Corp(config-if)#
description Switch Port connection to WWW Server
Corp(config-if)#
no shutdown
Corp(config-if)#
int f1/1
Corp(config-if)#
description Switch Port connection to Email Server
Corp(config-if)#
no shutdown
Corp(config-if)#
int f1/2
Corp(config-if)#
description Switch Port connection to DNS Server
Corp(config-if)#
no shutdown
----------------------------------------------------------------------------------------------------------------
Corp(config-if)#
int s0/0/0
Corp(config-if)#
description 1st Connection to R1
Corp(config-if)#
ip address 10.1.2.1 255.255.255.0
Corp(config-if)#
no shut
Corp(config-if)#
int s0/0/1
Corp(config-if)#
description 2nd Connection to R1
Corp(config-if)#
ip address 10.1.3.1 255.255.255.0
Corp(config-if)#
no shut
Corp(config-if)#
int s0/1/0
Corp(config-if)#
description Connection to R2
Corp(config-if)#
ip address 10.1.4.1 255.255.255.0
Corp(config-if)#
no shut
Corp(config-if)#
int fa0/0
Corp(config-if)#
description Connection to R3
Corp(config-if)#
ip address 10.1.5.1 255.255.255.0
Corp(config-if)#
no shut
----------------------------------------------------------------------------------------------------------------
Corp(config-if)#
line con 0
Corp(config-if)#
password console
Corp(config-if)#
login
Corp(config-if)#
logging synchro
Corp(config-if)#
exec-timeout 0 0
----------------------------------------------------------------------------------------------------------------
Corp(config-if)#
line aux 0
Corp(config-if)#
password aux
Corp(config-if)#
login
Corp(config-if)#
exit
----------------------------------------------------------------------------------------------------------------
Corp(config)#
line vty ?
<1-15>Last Line number
Corp(config)#
line vty 0 15
Corp(config-if)#
password telnet
Corp(config-if)#
login
Corp(config-if)#
exit
----------------------------------------------------------------------------------------------------------------
Corp(config)#
no ip domain lookup
Corp(config)#
banner motd # This is my Corp 2811 ISR Router #
Ctrl + Z
%SYS-5-CONFIG_I: Configured from console by console
(Ctrl-Z: When in a config mode, ends the config mode and returns you to privileged EXEC mode.... same as typing exit(?))
Corp#
copy run start
Destination filename [startup-config]?
Building configuration...
[OK]
----------------------------------------------------------------------------------------------------------------
Corp#
show ip int br
Interface IP-Address OK? Method Status Protocol
FastEthernet0/0 10.1.5.1 YES manual up down
FastEthernet0/1 unassigned YES unset administratively down down
Serial0/0/0 10.1.2.1 YES manual down down
Serial0/0/1 10.1.3.1 YES manual down down
Serial0/1/0 10.1.4.1 YES manual down down
Serial0/1/1 unassigned YES unset administratively down down
FastEthernet1/0 unassigned YES unset up up
FastEthernet1/1 unassigned YES unset up up
FastEthernet1/2 unassigned YES unset up up
FastEthernet1/3 unassigned YES unset administratively down down
FastEthernet1/4 unassigned YES unset administratively down down
FastEthernet1/5 unassigned YES unset administratively down down
FastEthernet1/6 unassigned YES unset administratively down down
FastEthernet1/7 unassigned YES unset administratively down down
FastEthernet1/8 unassigned YES unset administratively down down
FastEthernet1/9 unassigned YES unset administratively down down
FastEthernet1/10 unassigned YES unset administratively down down
FastEthernet1/11 unassigned YES unset administratively down down
FastEthernet1/12 unassigned YES unset administratively down down
FastEthernet1/13 unassigned YES unset administratively down down
FastEthernet1/14 unassigned YES unset administratively down down
FastEthernet1/15 unassigned YES unset administratively down down
Vlan1 10.1.1.1 YES manual up up
----------------------------------------------------------------------------------------------------------------
Corp#
show run
Building configuration...
Current configuration : 2073 bytes
!
version 15.1
no service timestamps log datetime msec
no service timestamps debug datetime msec
no service password-encryption
!
hostname Corp
!
!
!
enable secret 5 $1$mERr$V5ujdIM9bTB/I.ipB0gkJ0
!
!
!
!
!
!
no ip cef
no ipv6 cef
!
!
!
!
license udi pid CISCO2811/K9 sn FTX1017U440-
!
!
!
!
!
!
!
!
!
no ip domain-lookup
!
!
spanning-tree mode pvst
!
!
!
!
!
!
interface FastEthernet0/0
description connection to R3
ip address 10.1.5.1 255.255.255.0
duplex auto
speed auto
!
interface FastEthernet0/1
no ip address
duplex auto
speed auto
shutdown
!
interface Serial0/0/0
description 1st connection to R1
ip address 10.1.2.1 255.255.255.0
clock rate 2000000
!
interface Serial0/0/1
description 2nd connection to R1
ip address 10.1.3.1 255.255.255.0
clock rate 2000000
!
interface Serial0/1/0
description connection to R2
ip address 10.1.4.1 255.255.255.0
!
interface Serial0/1/1
no ip address
clock rate 2000000
shutdown
!
interface FastEthernet1/0
description switch port connection to WWW Server
!
interface FastEthernet1/1
description switch port connection to Email Server
!
interface FastEthernet1/2
description switch port connection to DNS Server
!
interface FastEthernet1/3
shutdown
!
interface FastEthernet1/4
shutdown
!
interface FastEthernet1/5
shutdown
!
interface FastEthernet1/6
shutdown
!
interface FastEthernet1/7
shutdown
!
interface FastEthernet1/8
shutdown
!
interface FastEthernet1/9
shutdown
!
interface FastEthernet1/10
shutdown
!
interface FastEthernet1/11
shutdown
!
interface FastEthernet1/12
shutdown
!
interface FastEthernet1/13
shutdown
!
interface FastEthernet1/14
shutdown
!
interface FastEthernet1/15
shutdown
!
interface Vlan1
description Switch Card to Core Network
ip address 10.1.1.1 255.255.255.0
!
ip classless
!
ip flow-export version 9
!
!
!
banner motd ^C This is my Corp 2811 ISR Router ^C
!
!
!
!
!
line con 0
exec-timeout 0 0
password console
logging synchronous
login
!
line aux 0
password aux
login
!
line vty 0 4
password telnet
login
line vty 5 15
password telnet
login
!
!
!
end
-----------------------------------------------------------------------------------------------------------------------
more configurations:
R1
Router(config)#
hostname R1
R1(config)#
enable secret todd
R1(config)#
int s0/0/0
R1(config-if)#
ip address 10.1.2.2 255.255.255.0
R1(config-if)#
Decription 1st connection to corp router
R1(config-if)#
no shut
-----------------------------------------------------------------------------------------------
R1(config-if)#
int s0/0/1
R1(config-if)#
ip address 10.1.3.2 255.255.255.0
R1(config-if)#
Decription 2nd connection to corp router
R1(config-if)#
no shut
-----------------------------------------------------------------------------------------------
R1(config-if)#
int f0/0
R1(config-if)#
ip address 192.168.10.1 255.255.255.0
R1(config-if)#
Decription connection to finance
R1(config-if)#
no shut
-----------------------------------------------------------------------------------------------
R1(config-if)#
int f0/1
R1(config-if)#
ip address 192.168.20.1 255.255.255.0
R1(config-if)#
Decription connection to marketing
R1(config-if)#
no shut
R1(config-if)#
exit
-----------------------------------------------------------------------------------------------
R1(config)#
line con 0
R1(config-line)#
password console
R1(config-line)#
login
R1(config-line)#
logging synchronous
R1(config-line)#
exec-timeout 0 0
-----------------------------------------------------------------------------------------------
R1(config-line)#
line aux 0
R1(config-line)#
password aux
R1(config-line)#
login
R1(config-line)#
exit
-----------------------------------------------------------------------------------------------
R1(config)#
line vty 0 ?
<0-15> Last Line number
R1(config)#
line vty 0 807
R1(config-line)#
password telnet
R1(config-line)#
login
R1(config-line)#
banner motd # This is my R1 Router #
R1(config-line)#
exit
-----------------------------------------------------------------------------------------------
R1(config)#
no ip domain-lookup
R1(config)#
exit
R1#
copy run start
R2
Router(config)#
hostname R2
R2(config)#
enable secret todd
R2(config)#
int s0/0/0
R2(config-if)#
ip address 10.1.4.2 255.255.255.0
R2(config-if)#
description connection to corp router
R2(config-if)#
no shut
-----------------------------------------------------------------------------------------------
R2(config-if)#
int f0/0
R2(config-if)#
ip address 192.168.30.1 255.255.255.0
R2(config-if)#
description connection to sales PC
R2(config-if)#
no shut
-----------------------------------------------------------------------------------------------
R2(config-if)#
int f0/1
R2(config-if)#
ip address 192.168.40.1 255.255.255.0
R2(config-if)#
description connection to HR pc
R2(config-if)#
no shut
-----------------------------------------------------------------------------------------------
R2(config-if)#
line con 0
R2(config-line)#
password console
R2(config-line)#
login
R2(config-line)#
logging synchronous
R2(config-line)#
exec-timeout 0 0
-----------------------------------------------------------------------------------------------
R2(config-line)#
line aux 0
R2(config-line)#
password aux
R2(config-line)#
login
R2(config-line)#
exit
-----------------------------------------------------------------------------------------------
R2(config)#
line vty 0 ?
<0-15> Last Line number
R2(config)#
line vty 0 807
R2(config-line)#
password telnet
R2(config-line)#
login
R2(config-line)#
banner motd # This is my R1 Router #
R2(config-line)#
exit
-----------------------------------------------------------------------------------------------
R2(config)#
no ip domain-lookup
R2(config)#
exit
R2#
copy run start
R3
Router(config)#
hostname R3
R3(config)#
enable secret todd
R3(config)#
int f0/0
R3(config-if)#
ip address 10.1.5.2 255.255.255.0
R3(config-if)#
description connection to corp router
R3(config-if)#
no shut
-----------------------------------------------------------------------------------------------
R3(config-if)#
int dot11radio0/0/0
R3(config-if)#
ip address 172.16.10.1 255.255.255.0
R3(config-if)#
description WLAN for mobile user
R3(config-if)#
no shut
R3(config-if)#
ssid ADMIN
stuck here 2-5-22-- packet tracer isnt taking me into the config-if-ssid prompt
R3(config-if-ssid)#
guest-mode
R3(config-if-ssid)#
authentication open
R3(config-if-ssid)#
ingrastructure-ssid
R3(config-if-ssid)#
exit
-----------------------------------------------------------------------------------------------
R3(config-if)#
line con 0
R3(config-line)#
password console
R3(config-line)#
login
R3(config-line)#
logging synchronous
R3(config-line)#
exec-timeout 0 0
-----------------------------------------------------------------------------------------------
R3(config-line)#
line aux 0
R3(config-line)#
password aux
R3(config-line)#
login
R3(config-line)#
exit
-----------------------------------------------------------------------------------------------
R3(config)#
line vty 0 ?
<0-15> Last Line number
R3(config)#
line vty 0 807
R3(config-line)#
password telnet
R3(config-line)#
login
R3(config-line)#
banner motd # This is my R1 Router #
R3(config-line)#
exit
-----------------------------------------------------------------------------------------------
R3(config)#
no ip domain-lookup
R3(config)#
exit
R3#
copy run start
PROBLEM
i cant get into conf-if-ssid prompt
R3(config-if)#
ssid ADMIN
%LINK-5-CHANGED: Interface Dot11Radio0/0/0, changed state to administratively down
%LINEPROTO-5-UPDOWN: Line protocol on Interface Dot11Radio0/0/0, changed state to down
%LINK-5-CHANGED: Interface Dot11Radio0/0/0, changed state to up
%LINEPROTO-5-UPDOWN: Line protocol on Interface Dot11Radio0/0/0, changed state to up
R3(config-if)#
research led me to this thread, which is a dead end:
further research led me here:
R3(config)# global config mode
R3(config)#
dot11 ssid ADMIN
creates an SSID or lets you config an existing SSID
R3(config-ssid)#
guest-mode
R3(config-ssid)#
%LINK-5-CHANGED: Interface Dot11Radio0/0/0, changed state to administratively down
%LINEPROTO-5-UPDOWN: Line protocol on Interface Dot11Radio0/0/0, changed state to down
%LINK-5-CHANGED: Interface Dot11Radio0/0/0, changed state to up
%LINEPROTO-5-UPDOWN: Line protocol on Interface Dot11Radio0/0/0, changed state to up
R3(config-ssid)#
authentication open
R3(config-ssid)#
%LINK-5-CHANGED: Interface Dot11Radio0/0/0, changed state to administratively down
%LINEPROTO-5-UPDOWN: Line protocol on Interface Dot11Radio0/0/0, changed state to down
%LINK-5-CHANGED: Interface Dot11Radio0/0/0, changed state to up
%LINEPROTO-5-UPDOWN: Line protocol on Interface Dot11Radio0/0/0, changed state to up
R3(config-ssid)#
infrastructure-ssid
R3(config-ssid)#infrastructure-ssid
^
% Invalid input detected at '^' marker.
this command given by the book doesnt appear to be valid
R3(config-ssid)#
?
authentication authentication method
exit Exit from ssid sub mode
guest-mode guest ssid
no Negate a command or set it's defaults
wpa-psk Configure Wi-Fi Protected Access pre-shared key
back into the interface to see what the options are
R3(config-ssid)#
int dot110/0/0
R3(config-if)#
?
arp Set arp type (arpa, probe, snap) or timeout or log options
bandwidth Set bandwidth informational parameter
cdp CDP interface subcommands
crypto Encryption/Decryption commands
delay Specify interface throughput delay
description Interface specific description
encryption Configure dot11 encryption parameters
exit Exit from interface configuration mode
fair-queue Enable Fair Queuing on an Interface
hold-queue Set hold queue depth
ip Interface Internet Protocol config commands
mac-address Manually set interface MAC address
mtu Set the interface Maximum Transmission Unit (MTU)
no Negate a command or set its defaults
priority-group Assign a priority group to an interface
service-policy Configure QoS Service Policy
shutdown Shutdown the selected interface
speed Set allowed radio bit rates
ssid Configure radio service set parameters
tx-ring-limit Configure PA level transmit ring limit
i'll consider the problem *mostly* solved. I was able to assign the SSD.
The infrastructure command may be expendable in this case... to be determined
here is our configuration for R3
R3#
show run
Building configuration...
Current configuration : 1682 bytes
!
version 15.1
no service timestamps log datetime msec
no service timestamps debug datetime msec
no service password-encryption
!
hostname R3
!
!
!
enable secret 5 $1$mERr$V5ujdIM9bTB/I.ipB0gkJ0
!
!
ip dhcp excluded-address 172.16.10.1 172.16.10.10
!
ip dhcp pool Admin
network 172.16.10.0 255.255.255.0
default-router 172.16.10.1
!
dot11 ssid ADMIN
authentication open
guest-mode
!
dot11 ssid ADMIN2
authentication open
guest-mode
!
!
!
ip cef
no ipv6 cef
!
!
!
!
license udi pid CISCO2811/K9 sn FTX1017RE40-
!
!
!
!
!
!
!
!
!
no ip domain-lookup
ip name-server 172.16.10.4
!
!
spanning-tree mode pvst
!
!
!
!
!
!
interface FastEthernet0/0
description connection to corp router
ip address 10.1.5.2 255.255.255.0
duplex auto
speed auto
!
interface FastEthernet0/1
no ip address
duplex auto
speed auto
shutdown
!
interface Dot11Radio0/0/0
description WAN for mobile
ip address 172.16.10.1 255.255.255.0
speed 12.0 18.0 24.0 36.0 48.0 54.0 6.0 9.0 basic-1.0 basic-11.0 basic-2.0 basic-5.5
ssid ADMIN2
!
interface Dot11Radio0/0/1
no ip address
speed 18.0 36.0 48.0 54.0 9.0 basic-12.0 basic-24.0 basic-6.0
!
interface Serial0/1/0
no ip address
clock rate 2000000
!
interface Serial0/1/1
no ip address
clock rate 2000000
!
interface Vlan1
no ip address
shutdown
!
router rip
version 2
network 10.0.0.0
network 172.16.0.0
!
ip classless
ip route 0.0.0.0 0.0.0.0 10.1.5.1
!
ip flow-export version 9
!
!
!
banner motd ^C this is R3 $
this is R3 ^C
!
!
!
!
!
line con 0
exec-timeout 0 0
password console
logging synchronous
login
!
line aux 0
password aux
login
!
line vty 0 4
password telnet
login
line vty 5 15
password telnet
login
!
!
!
end
to summarize...
the book is a little off here.
-----------------------------------------------------------------------------------------------
R3(config-if)#
int dot11radio0/0/0
R3(config-if)#
ip address 172.16.10.1 255.255.255.0
R3(config-if)#
description WLAN for mobile user
R3(config-if)#
no shut
at this point we have created a wireless interface with an IP address but no SSID exists on this router
interface Dot11Radio0/0/0
description test router 2
ip address 172.16.10.1 255.255.255.0
speed 12.0 18.0 24.0 36.0 48.0 54.0 6.0 9.0 basic-1.0 basic-11.0 basic-2.0 basic-5.5
Trying to use the command "ssid ADMIN" doesnt work here. The below commands are invalid here:
R3(config-if)#
ssid ADMIN
R3(config-if-ssid)#
guest-mode
R3(config-if-ssid)#
authentication open
R3(config-if-ssid)#
ingrastructure-ssid
R3(config-if-ssid)#
exit
-----------------------------------------------------------------------------------------------
We need to drop out of config-if, back to config, and enter SSID config mode
-----------------------------------------------------------------------------------------------
R3(config-if)#
exit
R3(config)#
dot11 ssid ADMIN2 creates an ssid named ADMIN2, and puts us into SSID config mode
R3(config-ssid)#
guest-mode
R3(config-ssid)#
authentication open
then out of config-ssid and back to interface config
R3(config-ssid)#
exit
R3(config)
int dot11r0/0/0
R3(config-if)
?
arp Set arp type (arpa, probe, snap) or timeout or log options
bandwidth Set bandwidth informational parameter
cdp CDP interface subcommands
crypto Encryption/Decryption commands
delay Specify interface throughput delay
description Interface specific description
encryption Configure dot11 encryption parameters
exit Exit from interface configuration mode
fair-queue Enable Fair Queuing on an Interface
hold-queue Set hold queue depth
ip Interface Internet Protocol config commands
mac-address Manually set interface MAC address
mtu Set the interface Maximum Transmission Unit (MTU)
no Negate a command or set its defaults
priority-group Assign a priority group to an interface
service-policy Configure QoS Service Policy
shutdown Shutdown the selected interface
speed Set allowed radio bit rates
ssid Configure radio service set parameters
tx-ring-limit Configure PA level transmit ring limit
we have the option for ssid
R3(config-if)
ssid ADMIN2
%LINK-5-CHANGED: Interface Dot11Radio0/0/0, changed state to administratively down
%LINEPROTO-5-UPDOWN: Line protocol on Interface Dot11Radio0/0/0, changed state to down
%LINK-5-CHANGED: Interface Dot11Radio0/0/0, changed state to up
%LINEPROTO-5-UPDOWN: Line protocol on Interface Dot11Radio0/0/0, changed state to up
the router resets the interface..
-----------------------------------------------------------------------------------------------
R3(config-if)
do show run
[cut]
!
!
dot11 ssid ADMIN2
authentication open
guest-mode
!
!
[cut]
!
interface Dot11Radio0/0/0
description test router 2
ip address 172.16.10.1 255.255.255.0
speed 12.0 18.0 24.0 36.0 48.0 54.0 6.0 9.0 basic-1.0 basic-11.0 basic-2.0 basic-5.5
ssid ADMIN2
!
[cut]
the SSID is created and assigned to the interface
To summarize.
Wrong: create the dot11 interface, then create the SSID from CONFIG-IF mode, which puts you into CONFIG-IF-SSID (there is no such mode on this router) mode, then modify the ssid from there...
Correct: create the dot11 interface. Exit CONFIG-IF and go back to GLOBAL CONFIG. Create the SSID which puts you in CONFIG-SSID mode.
Configure the ssid. Then exit CONFIG-SSID. Back into CONFIG-IF, assign the SSID
We have one more task for R3- Configuring the DHCP pool for wireless clients.
R3(config)#
ip dhcp pool Admin creating the pool name as "Admin"
R3(dhcp-config)#
network 172.16.10.0 255.255.255.0
R3(dhcp-config)#
default-router 172.16.10.1 aka default-gateway for clients in the pool
R3(dhcp-config)#
ip name-server 172.16.10.4 dns server
*automatically exits dhcp-config prompt*
R3(config)#
ip dhcp excluded-address 172.16.10.1 172.16.10.10 excludes the range given
172.16.10.1 is the router interface- we need to specifically exclude it from the pool
this setup should allow the wireless client to pick up an IP after connecting to the open SSID.
However, I was having trouble at first-
even though I seemed to have the SSID set correctly, i was hitting a WEP password prompt
i didnt see any obvious issues with the wifi module im using on the laptop:
The Linksys-WPC300N module provides one 2.4GHz wireless interface suitable for connection to wireless networks.
The module supports protocols that use Ethernet for LAN access.
I ended up creating a new SSID, with the same settings as the original:
R3(config)#
dot11 ssid ADMIN2
R3(config-ssid)#
guest-mode
R3(config-ssid)#
authentication open
and then I assigned the ip address to ssid ADMIN2 instead of the orginal ADMIN ssid
R3(config)#
int dot110/0/0
R3(config-if)#
ip address 172.16.10.1 255.255.255.0
R3(config-if)#
description WLAN for mobile user
R3(config-if)#
no shut
R3(config-if)#
ssid ADMIN2
R3#
show run
Building configuration...
Current configuration : 1467 bytes
!
version 15.1
no service timestamps log datetime msec
no service timestamps debug datetime msec
no service password-encryption
!
hostname R3
!
!
!
enable secret 5 $1$mERr$V5ujdIM9bTB/I.ipB0gkJ0
!
!
ip dhcp excluded-address 172.16.10.1 172.16.10.10
!
ip dhcp pool Admin
network 172.16.10.0 255.255.255.0
default-router 172.16.10.1
!
dot11 ssid ADMIN
authentication open
guest-mode
!
dot11 ssid ADMIN2
authentication open
guest-mode
!
!
!
ip cef
no ipv6 cef
!
!
!
!
license udi pid CISCO2811/K9 sn FTX1017RE40-
!
!
!
!
!
!
!
!
!
no ip domain-lookup
ip name-server 172.16.10.4
!
!
spanning-tree mode pvst
!
!
!
!
!
!
interface FastEthernet0/0
description connection to corp router
ip address 10.1.5.2 255.255.255.0
duplex auto
speed auto
!
interface FastEthernet0/1
no ip address
duplex auto
speed auto
shutdown
!
interface Dot11Radio0/0/0
description WAN for mobile
ip address 172.16.10.1 255.255.255.0
speed 12.0 18.0 24.0 36.0 48.0 54.0 6.0 9.0 basic-1.0 basic-11.0 basic-2.0 basic-5.5
ssid ADMIN2
!
interface Dot11Radio0/0/1
no ip address
speed 18.0 36.0 48.0 54.0 9.0 basic-12.0 basic-24.0 basic-6.0
!
interface Vlan1
no ip address
shutdown
!
ip classless
!
ip flow-export version 9
!
!
!
banner motd ^C this is R3 $
this is R3 ^C
!
!
!
!
!
line con 0
exec-timeout 0 0
password console
logging synchronous
login
!
line aux 0
password aux
login
!
line vty 0 4
password telnet
login
line vty 5 15
password telnet
login
!
!
!
end
Recall the DHCP configuration on R3:
R3(config)#
ip dhcp pool Admin creating the pool name as "Admin"
R3(dhcp-config)#
network 172.16.10.0 255.255.255.0
R3(dhcp-config)#
default-router 172.16.10.1 aka default-gateway for clients in the pool
R3(dhcp-config)#
ip name-server 172.16.10.4 dns server
*automatically exits dhcp-config prompt*
R3(config)#
ip dhcp excluded-address 172.16.10.1 172.16.10.10 excludes the range given
172.16.10.1 is the router interface- we need to specifically exclude it from the pool
we can check the configuration:
R3#
show ip dhcp pool
Pool Admin :
Utilization mark (high/low) : 100 / 0
Subnet size (first/next) : 0 / 0
Total addresses : 254
Leased addresses : 1
Excluded addresses : 1
Pending event : none
1 subnet is currently in the pool
Current index IP address range Leased/Excluded/Total
172.16.10.1 172.16.10.1 - 172.16.10.254 1 / 1 / 254
R3#
show ip dhcp binding
IP address Client-ID/ Lease expiration Type
Hardware address
172.16.10.11 00D0.979A.733B -- Automatic
the show command is becoming more familiar
R3#
show ip?
access-lists List access lists
arp IP ARP table
bgp BGP information
cache IP fast-switching route cache
cef Cisco Express Forwarding
dhcp Show items in the DHCP database
eigrp IP-EIGRP show commands
inspect CBAC (Context Based Access Control) information
interface IP interface status and configuration
ips IPS (Intrusion Prevention System) information
nat IP NAT information
nbar Network-Based Application Recognition
ospf OSPF information
protocols IP routing protocol process parameters and statistics
rip IP RIP show commands
route IP routing table
ssh Information on SSH
we'll use show ip route soon on all the routers. For now, here is the output for R3:
R3#
show ip route
Codes: L - local, C - connected, S - static, R - RIP, M - mobile, B - BGP
D - EIGRP, EX - EIGRP external, O - OSPF, IA - OSPF inter area
N1 - OSPF NSSA external type 1, N2 - OSPF NSSA external type 2
E1 - OSPF external type 1, E2 - OSPF external type 2, E - EGP
i - IS-IS, L1 - IS-IS level-1, L2 - IS-IS level-2, ia - IS-IS inter area
* - candidate default, U - per-user static route, o - ODR
P - periodic downloaded static route
Gateway of last resort is not set
10.0.0.0/8 is variably subnetted, 2 subnets, 2 masks
C 10.1.5.0/24 is directly connected, FastEthernet0/0
L 10.1.5.2/32 is directly connected, FastEthernet0/0
172.16.0.0/16 is variably subnetted, 2 subnets, 2 masks
C 172.16.10.0/24 is directly connected, Dot11Radio0/0/0
L 172.16.10.1/32 is directly connected, Dot11Radio0/0/0
Before moving on to the routing configurations, here is a review of the topology
I have switched over to the DrawIO diagram app to lay out the topology.
The Packet Tracer diagram becomes
too crowded to see the labels; it's labeling system forces awkward positioning of the objects; the interface
label's cant be moved, so if objects are too close together their labels cover eachother.. not good.
DrawIO allows a cleaner layout with plenty of room to label interfaces and ip addresses.
As a compromise, I'll use both.
I have the packet tracer objects spread out just enough to see the interfaces
and the label for each router. From here I can jump into the CLI for each device.
The DrawIO diagram allows me to cleary see IP addresses
I want to also review all of the configurations we just performed:
PROBLEM
The book specifies that of the two serial conections between R1 and Corp, there should be a DCE on each end..
Both of my DCE's are on the same end.
First lets be sure we understand what DCE means:
networkengineering.stackexchange.com/
One side of the link (DCE), has to transmit the clock signal, which controls the data rate, and the other side (DTE) receives the clock signal.
That is good enough for now. Note that while the book does specify in the diagram that each side should have a DCE, it was not actually mentioned in the configs.
We did not set a DCE or clock rate when conifguring those interfaces.
To fix this in my Packet Tracer topology, I did some quick research:
While this post wasnt pertaining to Packet Tracer, it got me thinking about the cable itself.
I deleted both of my existing serial connections and looked at the options for creating a new cable.
I noticed one is a DCE and one is a DTE:
Fixed the issue
back to the configuration overview: 4 routers, abbreviated show run output
Corp
interface FastEthernet0/0
description connection to R3
ip address 10.1.5.1 255.255.255.0
duplex auto
speed auto
!
interface FastEthernet0/1
no ip address
duplex auto
speed auto
shutdown
!
interface Serial0/0/0
description 1st connection to R1
ip address 10.1.2.1 255.255.255.0
!
interface Serial0/0/1
description 2nd connection to R1
ip address 10.1.3.1 255.255.255.0
clock rate 2000000
!
interface Serial0/1/0
description connection to R2
ip address 10.1.4.1 255.255.255.0
!
interface Vlan1
description Switch Card to Core Network
ip address 10.1.1.1 255.255.255.0
!
interface FastEthernet1/0
description switch port connection to WWW Server
switchport mode access
switchport nonegotiate
!
interface FastEthernet1/1
description switch port connection to Email Server
switchport mode access
switchport nonegotiate
!
interface FastEthernet1/2
description switch port connection to DNS Server
switchport mode access
switchport nonegotiate
!
R1
interface FastEthernet0/0
description connection to Finance
ip address 192.168.10.1 255.255.255.0
duplex auto
speed auto
!
interface FastEthernet0/1
description connection to Marketing
ip address 192.168.20.1 255.255.255.0
duplex auto
speed auto
!
interface Serial0/0/0
description 1st connection to Corp router
ip address 10.1.2.2 255.255.255.0
clock rate 2000000
!
interface Serial0/0/1
description 2nd connecction to Corp router
ip address 10.1.3.2 255.255.255.0
!
R2
interface FastEthernet0/0
description Connection to Sales PC
ip address 192.168.30.1 255.255.255.0
duplex auto
speed auto
!
interface FastEthernet0/1
description Connection to HR PC
ip address 192.168.40.1 255.255.255.0
duplex auto
speed auto
!
interface Serial0/0/0
description Connection to Corp Router
ip address 10.1.4.2 255.255.255.0
clock rate 2000000
!
interface Serial0/0/1
no ip address
clock rate 2000000
shutdown
!
R3
interface FastEthernet0/0
description connection to corp router
ip address 10.1.5.2 255.255.255.0
duplex auto
speed auto
!
interface FastEthernet0/1
no ip address
duplex auto
speed auto
shutdown
!
interface Dot11Radio0/0/0
description WAN for mobile
ip address 172.16.10.1 255.255.255.0
speed 12.0 18.0 24.0 36.0 48.0 54.0 6.0 9.0 basic-1.0 basic-11.0 basic-2.0 basic-5.5
ssid ADMIN2
and here is the output of show ip route for each router
Codes: C - connected, S - static, I - IGRP, R - RIP, M - mobile, B - BGP
D - EIGRP, EX - EIGRP external, O - OSPF, IA - OSPF inter area
N1 - OSPF NSSA external type 1, N2 - OSPF NSSA external type 2
E1 - OSPF external type 1, E2 - OSPF external type 2, E - EGP
i - IS-IS, L1 - IS-IS level-1, L2 - IS-IS level-2, ia - IS-IS inter area
* - candidate default, U - per-user static route, o - ODR
P - periodic downloaded static route
Gateway of last resort is not set
Corp
10.0.0.0/24 is subnetted, 2 subnets
C 10.1.2.0 is directly connected, Serial0/0/0
C 10.1.3.0 is directly connected, Serial0/0/1
C 192.168.10.0/24 is directly connected, FastEthernet0/0
C 192.168.20.0/24 is directly connected, FastEthernet0/1
R1
10.0.0.0/24 is subnetted, 2 subnets
C 10.1.2.0 is directly connected, Serial0/0/0
C 10.1.3.0 is directly connected, Serial0/0/1
C 192.168.10.0/24 is directly connected, FastEthernet0/0
C 192.168.20.0/24 is directly connected, FastEthernet0/1
R2
10.0.0.0/24 is subnetted, 1 subnets
C 10.1.4.0 is directly connected, Serial0/0/0
C 192.168.30.0/24 is directly connected, FastEthernet0/0
C 192.168.40.0/24 is directly connected, FastEthernet0/1
R3
10.0.0.0/8 is variably subnetted, 2 subnets, 2 masks
C 10.1.5.0/24 is directly connected, FastEthernet0/0
L 10.1.5.2/32 is directly connected, FastEthernet0/0
172.16.0.0/16 is variably subnetted, 2 subnets, 2 masks
C 172.16.10.0/24 is directly connected, Dot11Radio0/0/0
L 172.16.10.1/32 is directly connected, Dot11Radio0/0/0
Note that this is before we have configured any 'routing'. We are seeing configured, directly connected networks.
The output for R3 is particularly interesting
What does 'variably' subnetted mean, and what is the "L" next to these routes. And why do they have a mask of 32?
R3
10.0.0.0/8 is variably subnetted, 2 subnets, 2 masks
C 10.1.5.0/24 is directly connected, FastEthernet0/0
L 10.1.5.2/32 is directly connected, FastEthernet0/0
172.16.0.0/16 is variably subnetted, 2 subnets, 2 masks
C 172.16.10.0/24 is directly connected, Dot11Radio0/0/0
L 172.16.10.1/32 is directly connected, Dot11Radio0/0/0
Cisco forums
That makes sense, but my question is why did the other routing tables not behave the same way? R3 is the only one that shows "L" routes.
The book tells us we're using two different model routers, and indeed they are running different IOS versions:
NOTE that at the time the book was published IOS 15 was not released yet, so the book assumes all routers are running 12.4
But that still doesnt explain why Corp and R3 are behaving differently..
Corp
10.0.0.0/24 is subnetted, 2 subnets
C 10.1.2.0 is directly connected, Serial0/0/0
C 10.1.3.0 is directly connected, Serial0/0/1
C 192.168.10.0/24 is directly connected, FastEthernet0/0
C 192.168.20.0/24 is directly connected, FastEthernet0/1
R1
10.0.0.0/24 is subnetted, 2 subnets
C 10.1.2.0 is directly connected, Serial0/0/0
C 10.1.3.0 is directly connected, Serial0/0/1
C 192.168.10.0/24 is directly connected, FastEthernet0/0
C 192.168.20.0/24 is directly connected, FastEthernet0/1
R2
10.0.0.0/24 is subnetted, 1 subnets
C 10.1.4.0 is directly connected, Serial0/0/0
C 192.168.30.0/24 is directly connected, FastEthernet0/0
C 192.168.40.0/24 is directly connected, FastEthernet0/1
R3
10.0.0.0/8 is variably subnetted, 2 subnets, 2 masks
C 10.1.5.0/24 is directly connected, FastEthernet0/0
L 10.1.5.2/32 is directly connected, FastEthernet0/0
172.16.0.0/16 is variably subnetted, 2 subnets, 2 masks
C 172.16.10.0/24 is directly connected, Dot11Radio0/0/0
L 172.16.10.1/32 is directly connected, Dot11Radio0/0/0
how are Corp and R3 different?
The answer is, they are not...
I have accidentally displayed the R1 output to the Corp windows. Error in translating data from the IOS to this webpage..
here's the corrected output.
Corp
10.0.0.0/8 is variably subnetted, 10 subnets, 2 masks
C 10.1.1.0/24 is directly connected, Vlan1
L 10.1.1.1/32 is directly connected, Vlan1
C 10.1.2.0/24 is directly connected, Serial0/0/0
L 10.1.2.1/32 is directly connected, Serial0/0/0
C 10.1.3.0/24 is directly connected, Serial0/0/1
L 10.1.3.1/32 is directly connected, Serial0/0/1
C 10.1.4.0/24 is directly connected, Serial0/1/0
L 10.1.4.1/32 is directly connected, Serial0/1/0
C 10.1.5.0/24 is directly connected, FastEthernet0/0
L 10.1.5.1/32 is directly connected, FastEthernet0/0
R1
10.0.0.0/24 is subnetted, 2 subnets
C 10.1.2.0 is directly connected, Serial0/0/0
C 10.1.3.0 is directly connected, Serial0/0/1
C 192.168.10.0/24 is directly connected, FastEthernet0/0
C 192.168.20.0/24 is directly connected, FastEthernet0/1
R2
10.0.0.0/24 is subnetted, 1 subnets
C 10.1.4.0 is directly connected, Serial0/0/0
C 192.168.30.0/24 is directly connected, FastEthernet0/0
C 192.168.40.0/24 is directly connected, FastEthernet0/1
R3
10.0.0.0/8 is variably subnetted, 2 subnets, 2 masks
C 10.1.5.0/24 is directly connected, FastEthernet0/0
L 10.1.5.2/32 is directly connected, FastEthernet0/0
172.16.0.0/16 is variably subnetted, 2 subnets, 2 masks
C 172.16.10.0/24 is directly connected, Dot11Radio0/0/0
L 172.16.10.1/32 is directly connected, Dot11Radio0/0/0
We do indeed see consistent behavior differences between IOS versions 12.4 and 15.1
recap Corp and R3 outputs:
update topology with Router versions
That covers the first half of Chapter 8. Now we are ready to configure IP routing on our network.
There are three ways: Static, Default, Dynamic
To set up static routes, we simply need to program the routes using the ip route command
Syntax
ip route
[
destination network
]
[
mask
]
[
next hop
]
[
exitinterface
]
[
administrative distance
]
[
permanent
]
destination network and mask
the network data we're adding to the routing table
next-hop address
the address of the next-hop router that will receive the packet and forward to the remote network.
This is the IP address of a router interface that is directly connected.
It must be pingable.
exit interface
can be used instead of next hop address
administrative distance
by default, static routes have an admin distance of 1 if you use a next hop, or 0 if you use exit interface.
You can change the value by adding an administrative weight at the end of the command. More on this later with dynamic routing.
permanent
if the interface is shut down or the router cant communicate to the next hp router, the route will automatically be discarded from the table by default.
The 'permanent' option keeps the entry in the routing table indefenitely.
-----------------------------------------------------------------------------------------------------
Corp has automatically picked up 5 routes that are directly connected:
10.1.1.0 to corp switch card
10.1.2.0 to R1
10.1.3.0 to R1
10.1.4.0 to R2
10.1.5.0 to R3
We need to program 5 more routes:
192.168.10.0 traverse R1
192.168.20.0 traverse R1
192.168.30.0 traverse R1
192.168.40.0 traverse R2
172.16.10.0 traverse R3
-----------------------------------------------------------------------------------------------------
R1 has automatically picked up 4 routes that are directly connected:
10.1.2.0
10.1.3.0
192.168.10.0
192.168.20.0
We need to program 6 more routes:
10.1.1.0
10.1.4.0
10.1.5.0
192.168.30.0
192.168.40.0
172.16.10.0
-----------------------------------------------------------------------------------------------------
R2 has automatically picked up 3 routes that are directly connected:
10.1.4.0
192.168.30.0
192.168.40.0
We need to program 7 more routes:
10.1.1.0
10.1.2.0
10.1.3.0
10.1.5.0
192.168.10.0
192.168.20.0
172.16.10.0
-----------------------------------------------------------------------------------------------------
R3 has automatically picked up 2 routes that are directly connected:
10.1.5.0
172.16.10.0
We need to program 8 more routes:
10.1.1.0
10.1.2.0
10.1.3.0
10.1.4.0
192.168.10.0
192.168.20.0
192.168.30.0
192.168.40.0
Notice the pattern- each router ends up with 10 routes
There are 10 routes total in this topology. AKA ten broadcast domains
Programming the routes
Corp
Corp(config)#
ip route 192.168.10.0 255.255.255.0 10.1.2.2 150
Corp(config)#
ip route 192.168.20.0 255.255.255.0 10.1.3.2 150
Corp(config)#
ip route 192.168.30.0 255.255.255.0 10.1.4.2 150
Corp(config)#
ip route 192.168.40.0 255.255.255.0 10.1.4.2 150
Corp(config)#
ip route 172.16.10.0 255.255.255.0 10.1.5.2 150
Corp(config)#
do show ip route
In the first line, the router is saying that a
classful A network is being subnetted
There are 5 routes directly connected
We see two lines per route (one for the network and one
for the interface(/32)-
10.0.0.0/8 is variably subnetted, 10 subnets, 2 masks
C 10.1.1.0/24 is directly connected, Vlan1
L 10.1.1.1/32 is directly connected, Vlan1
C 10.1.2.0/24 is directly connected, Serial0/0/0
L 10.1.2.1/32 is directly connected, Serial0/0/0
C 10.1.3.0/24 is directly connected, Serial0/0/1
L 10.1.3.1/32 is directly connected, Serial0/0/1
C 10.1.4.0/24 is directly connected, Serial0/1/0
L 10.1.4.1/32 is directly connected, Serial0/1/0
C 10.1.5.0/24 is directly connected, FastEthernet0/0
L 10.1.5.1/32 is directly connected, FastEthernet0/0
and 5 routes that require traversal of a router to reach
172.16.0.0/24 is subnetted, 1 subnets
S 172.16.10.0/24 [150/0] via 10.1.5.2
S 192.168.10.0/24 [150/0] via 10.1.2.2
S 192.168.20.0/24 [150/0] via 10.1.3.2
S 192.168.30.0/24 [150/0] via 10.1.4.2
S 192.168.40.0/24 [150/0] via 10.1.4.2
R1
R1(config)#
ip route 10.1.1.0 255.255.255.0 10.1.2.1 150
R1(config)#
ip route 10.1.4.0 255.255.255.0 10.1.3.1 150
R1(config)#
ip route 10.1.5.0 255.255.255.0 10.1.2.1 150
R1(config)#
ip route 192.168.30.0 255.255.255.0 10.1.3.1 150
R1(config)#
ip route 192.168.40.0 255.255.255.0 10.1.2.1 150
R1(config)#
ip route 172.16.10.0 255.255.255.0 10.1.3.1 150
the only way to get across the corp router is to go into it via 10.1.2.1 or 10.1.3.1
R1(config)#
do show ip route
10.0.0.0/24 is subnetted, 5 subnets
S 10.1.1.0 [150/0] via 10.1.2.1
C 10.1.2.0 is directly connected, Serial0/0/0
C 10.1.3.0 is directly connected, Serial0/0/1
S 10.1.4.0 [150/0] via 10.1.3.1
S 10.1.5.0 [150/0] via 10.1.2.1
172.16.0.0/24 is subnetted, 1 subnets
S 172.16.10.0 [150/0] via 10.1.3.1
C 192.168.10.0/24 is directly connected, FastEthernet0/0
C 192.168.20.0/24 is directly connected, FastEthernet0/1
S 192.168.30.0/24 [150/0] via 10.1.3.1
S 192.168.40.0/24 [150/0] via 10.1.2.1
R2
R2(config)#
iproute 10.1.1.0 255.255.255.0 10.1.4.1 150
R2(config)#
iproute 10.1.2.0 255.255.255.0 10.1.4.1 150
R2(config)#
iproute 10.1.3.0 255.255.255.0 10.1.4.1 150
R2(config)#
iproute 10.1.5.0 255.255.255.0 10.1.4.1 150
R2(config)#
iproute 192.168.10.0 255.255.255.0 10.1.4.1 150
R2(config)#
iproute 192.168.20.0 255.255.255.0 10.1.4.1 150
the only way to get across Corp is to go into it via 10.1.4.1
R2(config)#
do show ip route
10.0.0.0/24 is subnetted, 5 subnets
S 10.1.1.0 [150/0] via 10.1.4.1
S 10.1.2.0 [150/0] via 10.1.4.1
S 10.1.3.0 [150/0] via 10.1.4.1
C 10.1.4.0 is directly connected, Serial0/0/0
S 10.1.5.0 [150/0] via 10.1.4.1
172.16.0.0/24 is subnetted, 1 subnets
S 172.16.10.0 [150/0] via 10.1.4.1
S 192.168.10.0/24 [150/0] via 10.1.4.1
S 192.168.20.0/24 [150/0] via 10.1.4.1
C 192.168.30.0/24 is directly connected, FastEthernet0/0
C 192.168.40.0/24 is directly connected, FastEthernet0/1
R3
R3(config)#
ip route 10.1.1.0 255.255.255.0 fastethernet 0/0 150
R3(config)#
ip route 10.1.2.0 255.255.255.0 fastethernet 0/0 150
R3(config)#
ip route 10.1.3.0 255.255.255.0 fastethernet 0/0 150
R3(config)#
ip route 10.1.4.0 255.255.255.0 fastethernet 0/0 150
R3(config)#
ip route 192.168.10.0 255.255.255.0 fastethernet 0/0 150
R3(config)#
ip route 192.168.20.0 255.255.255.0 fastethernet 0/0 150
R3(config)#
ip route 192.168.30.0 255.255.255.0 fastethernet 0/0 150
R3(config)#
ip route 192.168.40.0 255.255.255.0 fastethernet 0/0 150
the only way to get across Corp is to EXIT R3 via F0/0
R3(config)#
do show ip route
10.0.0.0/8 is variably subnetted, 6 subnets, 2 masks
S 10.1.1.0/24 is directly connected, FastEthernet0/0
S 10.1.2.0/24 is directly connected, FastEthernet0/0
S 10.1.3.0/24 is directly connected, FastEthernet0/0
S 10.1.4.0/24 is directly connected, FastEthernet0/0
C 10.1.5.0/24 is directly connected, FastEthernet0/0
L 10.1.5.2/32 is directly connected, FastEthernet0/0
172.16.0.0/16 is variably subnetted, 2 subnets, 2 masks
C 172.16.10.0/24 is directly connected, Dot11Radio0/0/0
L 172.16.10.1/32 is directly connected, Dot11Radio0/0/0
S 192.168.10.0/24 is directly connected, FastEthernet0/0
S 192.168.20.0/24 is directly connected, FastEthernet0/0
S 192.168.30.0/24 is directly connected, FastEthernet0/0
S 192.168.40.0/24 is directly connected, FastEthernet0/0
before verifying connectivity across the network, we need to make sure all of our hosts are set. The book is giving us the IP addresses for the servers:
Server Gateway 10.1.1.1
ServerWeb 10.1.1.2
ServerEmail 10.1.1.3
ServerDNS 10.1.1.4
Now we can do some testing across the network:
R3#
ping 10.1.2.2
traverse Corp to R1
R3#
ping 10.1.1.1
traverse Corp to a Corp interface we arent directly connected to
R3#
ping 10.1.1.2
traverse Corp to Web server
R3#
ping 10.1.1.3
traverse Corp to Email server
R3#
ping 10.1.1.4
traverse Corp to DNS server
MobileUser
ping 192.168.10.2
traverse R3, Corp, R1 to Finance client
MobileUser
tracert 192.168.10.2
traverse R3, Corp, R1 to Finance client
Tracing route to 192.168.10.2 over a maximum of 30 hops:
1 19 ms 5 ms 20 ms 172.16.10.1
2 20 ms 6 ms 11 ms 10.1.5.1
3 11 ms 15 ms 10 ms 10.1.3.2
4 9 ms 13 ms 22 ms 192.168.10.2
Trace complete.
notice how the trace doesnt count an egress as a hop, only an ingress
ALSO NOTE that tracert is a Windows command.
the IOS equivalent is traceroute
notice how the output differs from the Windows command
R3
traceroute 192.168.10.2
Type escape sequence to abort.
Tracing the route to 192.168.10.2
1 10.1.5.1 0 msec 0 msec 0 msec
2 10.1.2.2 6 msec 0 msec 5 msec
3 192.168.10.2 1 msec 4 msec 3 msec
Default Routing
we could have done this on R3
R3(config)#
ip route 0.0.0.0 0.0.0.0 10.1.5.1
as an alternative to this configuration on R3
R3(config)#
ip route 10.1.1.0 255.255.255.0 fastethernet 0/0 150
R3(config)#
ip route 10.1.2.0 255.255.255.0 fastethernet 0/0 150
R3(config)#
ip route 10.1.3.0 255.255.255.0 fastethernet 0/0 150
R3(config)#
ip route 10.1.4.0 255.255.255.0 fastethernet 0/0 150
R3(config)#
ip route 192.168.10.0 255.255.255.0 fastethernet 0/0 150
R3(config)#
ip route 192.168.20.0 255.255.255.0 fastethernet 0/0 150
R3(config)#
ip route 192.168.30.0 255.255.255.0 fastethernet 0/0 150
R3(config)#
ip route 192.168.40.0 255.255.255.0 fastethernet 0/0 150
the only way to get across Corp is to EXIT R3 via F0/0
This is called default routing. It should only be used on 'stub routers'- those with only one exit path out of the network.
if you try to put a default route on a non-stub router, you could create loops, since there will be more than one path to other routers...
Think of a default route as a static route that uses a wildcard address and mask. The wildcard is 0.0.0.0
to further analyze this comparison, I'm going to remove the routes from R3...
R3(config)#
no ip route 10.1.1.0 255.255.255.0 fastethernet0/0 150
R3(config)#
no ip route 10.1.2.0 255.255.255.0 fastethernet0/0 150
R3(config)#
no ip route 10.1.3.0 255.255.255.0 fastethernet0/0 150
R3(config)#
no ip route 10.1.4.0 255.255.255.0 fastethernet0/0 150
R3(config)#
no ip route 192.168.10.0 255.255.255.0 fastethernet0/0 150
R3(config)#
no ip route 192.168.20.0 255.255.255.0 fastethernet0/0 150
R3(config)#
no ip route 192.168.30.0 255.255.255.0 fastethernet0/0 150
R3(config)#
no ip route 192.168.40.0 255.255.255.0 fastethernet0/0 150
and then set the default route instead.
R3#
ip route 0.0.0.0 0.0.0.0 10.1.5.1 --- ingress at next hop
OR
R3#
ip route 0.0.0.0 0.0.0.0 Fa0/0 --- egress interface
Then compare the output of show ip route
static routes set
R3#
show ip route
Gateway of last resort is not set
10.0.0.0/8 is variably subnetted, 6 subnets, 2 masks
S 10.1.1.0/24 is directly connected, FastEthernet0/0
S 10.1.2.0/24 is directly connected, FastEthernet0/0
S 10.1.3.0/24 is directly connected, FastEthernet0/0
S 10.1.4.0/24 is directly connected, FastEthernet0/0
C 10.1.5.0/24 is directly connected, FastEthernet0/0
L 10.1.5.2/32 is directly connected, FastEthernet0/0
172.16.0.0/16 is variably subnetted, 2 subnets, 2 masks
C 172.16.10.0/24 is directly connected, Dot11Radio0/0/0
L 172.16.10.1/32 is directly connected, Dot11Radio0/0/0
S 192.168.10.0/24 is directly connected, FastEthernet0/0
S 192.168.20.0/24 is directly connected, FastEthernet0/0
S 192.168.30.0/24 is directly connected, FastEthernet0/0
S 192.168.40.0/24 is directly connected, FastEthernet0/0
default route set
R3#
show ip route
Gateway of last resort is 10.1.5.1 to network 0.0.0.0
10.0.0.0/8 is variably subnetted, 2 subnets, 2 masks
C 10.1.5.0/24 is directly connected, FastEthernet0/0
L 10.1.5.2/32 is directly connected, FastEthernet0/0
172.16.0.0/16 is variably subnetted, 2 subnets, 2 masks
C 172.16.10.0/24 is directly connected, Dot11Radio0/0/0
L 172.16.10.1/32 is directly connected, Dot11Radio0/0/0
S* 0.0.0.0/0 [1/0] via 10.1.5.1
two directly connected networks- 10.1.5.0 and 172.16.10.0
anything not included in those networks goes to ingress of attached neighbor Corp 10.1.5.1
in this toplogy, that includes:
192.168.10.0
192.168.20.0
192.168.30.0
192.168.40.0
and
10.1.1.0
10.1.2.0
10.1.3.0
10.1.4.0
RIP Routing Information Protocol
R1(config)#
router ?
bgp Border Gateway Protocol (BGP)
eigrp Enhanced Interior Gateway Routing Protocol (EIGRP)
ospf Open Shortest Path First (OSPF)
rip Routing Information Protocol (RIP)
set RIP on Corp
Corp(config)#
router rip
Corp(config-router)#
network 10.0.0.0
set RIP on R1
R1(config)#
router rip
R1(config-router)#
network 10.0.0.0
R1 routing table
R1(config)#
do show ip route
10.0.0.0/24 is subnetted, 5 subnets
R 10.1.1.0 [120/1] via 10.1.2.1, 00:00:21, Serial0/0/0
[120/1] via 10.1.3.1, 00:00:21, Serial0/0/1
C 10.1.2.0 is directly connected, Serial0/0/0
C 10.1.3.0 is directly connected, Serial0/0/1
R 10.1.4.0 [120/1] via 10.1.2.1, 00:00:21, Serial0/0/0
[120/1] via 10.1.3.1, 00:00:21, Serial0/0/1
R 10.1.5.0 [120/1] via 10.1.2.1, 00:00:21, Serial0/0/0
[120/1] via 10.1.3.1, 00:00:21, Serial0/0/1
172.16.0.0/24 is subnetted, 1 subnets
S 172.16.10.0 [150/0] via 10.1.3.1
C 192.168.10.0/24 is directly connected, FastEthernet0/0
C 192.168.20.0/24 is directly connected, FastEthernet0/1
S 192.168.30.0/24 [150/0] via 10.1.3.1
S 192.168.40.0/24 [150/0] via 10.1.2.1
here's R1 before RIP, with only static routes set:
R1(config)#
do show ip route
10.0.0.0/24 is subnetted, 5 subnets
S 10.1.1.0 [150/0] via 10.1.2.1
C 10.1.2.0 is directly connected, Serial0/0/0
C 10.1.3.0 is directly connected, Serial0/0/1
S 10.1.4.0 [150/0] via 10.1.3.1
S 10.1.5.0 [150/0] via 10.1.2.1
172.16.0.0/24 is subnetted, 1 subnets
S 172.16.10.0 [150/0] via 10.1.3.1
C 192.168.10.0/24 is directly connected, FastEthernet0/0
C 192.168.20.0/24 is directly connected, FastEthernet0/1
S 192.168.30.0/24 [150/0] via 10.1.3.1
S 192.168.40.0/24 [150/0] via 10.1.2.1
These RIP routes are being advertised as available *to other RIP routers*.
CORP is advertisting THREE routes via RIP to R1 right now
10.1.1.0
10.1.4.0
10.1.5.0
access to those networks can be achieved by R1 by going THROUGH CORP via ingress .2.1 or .3.1
The advantage..... is that we didnt statically program these routes
we engaged RIP, on BOTH routers- R1 and Corp, and handed them BOTH the network "10.0.0.0"
So, why did RIP choose to display these particular routes
Keep in mind that the output above is from R1 only... In the context of the R1 ROUTER ONLY,
there are three relevant routes within the "10.0.0.0" parameter we specified. The three routes involve Corp.
Corp is sending RIP data about these routes to Corp.
Lets look closer at how this is happening:
here's our starting point before any RIP is set
here's our routing tables after i set RIP with 10.0.0.0 on both..
FIRST i set it on Corp, then R1.(per the book's instructions) As a result we are seeing RIP routes in R1 only....
then I went back to a fresh packet tracer file with no RIP set. And I set RIP in the opposite order;
FIRST i set it on R1, then Corp. And again, we are seeing RIP routes in R1 only....
I wanted to prove that it didnt matter which order we enabled RIP on the two routers. What matters here is that
we enable RIP on both of them with the criteria of 10.0.0.0
Recall the topology:
if Corp and R1 are set for RIP and given the criteria 10.0.0.0, meaning that we are trying to reach networks
within that range, then it follows that Corp will advertise 1.1.0, 1.4.0, and 1.5.0 to R1, because Corp stands between those networks
and R1
"Hi R1, I'm Corp I have three networks that fall inside 10.0.0.0, and you can reach them through me via .2.1 or .3.1"
It also follows that Corp's routing table shows no RIP routes- because R1 isnt advertising any. R1 doesnt have any networks
in the 10.0.0.0 range that Corp could reach
To further clarify this, we'll proceed with the book's instructions. We'll now set more RIP routes on R1
R1(config)#
router rip
R1(config-router)#
network 192.168.10.0
R1(config-router)#
network 192.168.20.0
Corp routing table before RIP set on R1:
Corp#
show ip route
10.0.0.0/8 is variably subnetted, 10 subnets, 2 masks
C 10.1.1.0/24 is directly connected, Vlan1
L 10.1.1.1/32 is directly connected, Vlan1
C 10.1.2.0/24 is directly connected, Serial0/0/0
L 10.1.2.1/32 is directly connected, Serial0/0/0
C 10.1.3.0/24 is directly connected, Serial0/0/1
L 10.1.3.1/32 is directly connected, Serial0/0/1
C 10.1.4.0/24 is directly connected, Serial0/1/0
L 10.1.4.1/32 is directly connected, Serial0/1/0
C 10.1.5.0/24 is directly connected, FastEthernet0/0
L 10.1.5.1/32 is directly connected, FastEthernet0/0
172.16.0.0/24 is subnetted, 1 subnets
S 172.16.10.0/24 [150/0] via 10.1.5.2
S 192.168.10.0/24 [150/0] via 10.1.2.2
S 192.168.20.0/24 [150/0] via 10.1.3.2
S 192.168.30.0/24 [150/0] via 10.1.4.2
S 192.168.40.0/24 [150/0] via 10.1.4.2
Corp routing table after RIP set on R1:
Gateway of last resort is not set
10.0.0.0/8 is variably subnetted, 10 subnets, 2 masks
C 10.1.1.0/24 is directly connected, Vlan1
L 10.1.1.1/32 is directly connected, Vlan1
C 10.1.2.0/24 is directly connected, Serial0/0/0
L 10.1.2.1/32 is directly connected, Serial0/0/0
C 10.1.3.0/24 is directly connected, Serial0/0/1
L 10.1.3.1/32 is directly connected, Serial0/0/1
C 10.1.4.0/24 is directly connected, Serial0/1/0
L 10.1.4.1/32 is directly connected, Serial0/1/0
C 10.1.5.0/24 is directly connected, FastEthernet0/0
L 10.1.5.1/32 is directly connected, FastEthernet0/0
nothing changed so far
172.16.0.0/24 is subnetted, 1 subnets
S 172.16.10.0/24 [150/0] via 10.1.5.2
no change
R 192.168.10.0/24 [120/1] via 10.1.2.2, 00:00:08, Serial0/0/0
[120/1] via 10.1.3.2, 00:00:08, Serial0/0/1
RIP overrides static- 2 paths available now
R 192.168.20.0/24 [120/1] via 10.1.2.2, 00:00:08, Serial0/0/0
[120/1] via 10.1.3.2, 00:00:08, Serial0/0/1
RIP overrides static- 2 paths available now
S 192.168.30.0/24 [150/0] via 10.1.4.2
no change
S 192.168.40.0/24 [150/0] via 10.1.4.2
no change
"Hi Corp- I'm R1 and I have zero networks
that fall inside 10.0.0.0, however I do have some networks that fall within
192.168.20.0 and 192.168.10.0
and you can reach them through me(R1) if you ingress at .1.2.2 or .1.3.2"
ok, we have the concept down. Time to proceed and set up RIP on R2............
R2(config)#
router rip
R2(config-router)#
network 10.0.0.0
R2(config-router)#
network 192.168.30.0
R2(config-router)#
network 192.168.40.0
R2 before RIP enabled
R2#
show ip route
10.0.0.0/24 is subnetted, 5 subnets
S 10.1.1.0 [150/0] via 10.1.4.1
S 10.1.2.0 [150/0] via 10.1.4.1
S 10.1.3.0 [150/0] via 10.1.4.1
C 10.1.4.0 is directly connected, Serial0/0/0
S 10.1.5.0 [150/0] via 10.1.4.1
172.16.0.0/24 is subnetted, 1 subnets
S 172.16.10.0 [150/0] via 10.1.4.1
S 192.168.10.0/24 [150/0] via 10.1.4.1
S 192.168.20.0/24 [150/0] via 10.1.4.1
C 192.168.30.0/24 is directly connected, FastEthernet0/0
C 192.168.40.0/24 is directly connected, FastEthernet0/1
R2 after RIP added
R2#
show ip route
10.0.0.0/24 is subnetted, 5 subnets
R 10.1.1.0 [120/1] via 10.1.4.1, 00:00:24, Serial0/0/0
from corp
R 10.1.2.0 [120/1] via 10.1.4.1, 00:00:24, Serial0/0/0
from corp
R 10.1.3.0 [120/1] via 10.1.4.1, 00:00:24, Serial0/0/0
from corp
C 10.1.4.0 is directly connected, Serial0/0/0
R 10.1.5.0 [120/1] via 10.1.4.1, 00:00:24, Serial0/0/0
from corp
172.16.0.0/24 is subnetted, 1 subnets
S 172.16.10.0 [150/0] via 10.1.4.1
R 192.168.10.0/24 [120/2] via 10.1.4.1, 00:00:24, Serial0/0/0
from R1 via corp
R 192.168.20.0/24 [120/2] via 10.1.4.1, 00:00:24, Serial0/0/0
from R1 via corp
C 192.168.30.0/24 is directly connected, FastEthernet0/0
C 192.168.40.0/24 is directly connected, FastEthernet0/1
now lets compare the Corp and R1 routing tables- before RIP was set on R2 and after
Corp before R2 RIP
Corp#
show ip route
10.0.0.0/8 is variably subnetted, 10 subnets, 2 masks
C 10.1.1.0/24 is directly connected, Vlan1
L 10.1.1.1/32 is directly connected, Vlan1
C 10.1.2.0/24 is directly connected, Serial0/0/0
L 10.1.2.1/32 is directly connected, Serial0/0/0
C 10.1.3.0/24 is directly connected, Serial0/0/1
L 10.1.3.1/32 is directly connected, Serial0/0/1
C 10.1.4.0/24 is directly connected, Serial0/1/0
L 10.1.4.1/32 is directly connected, Serial0/1/0
C 10.1.5.0/24 is directly connected, FastEthernet0/0
L 10.1.5.1/32 is directly connected, FastEthernet0/0
172.16.0.0/24 is subnetted, 1 subnets
S 172.16.10.0/24 [150/0] via 10.1.5.2
R 192.168.10.0/24 [120/1] via 10.1.2.2, 00:00:02, Serial0/0/0
[120/1] via 10.1.3.2, 00:00:02, Serial0/0/1
R 192.168.20.0/24 [120/1] via 10.1.2.2, 00:00:02, Serial0/0/0
[120/1] via 10.1.3.2, 00:00:02, Serial0/0/1
from R1
S 192.168.30.0/24 [150/0] via 10.1.4.2
S 192.168.40.0/24 [150/0] via 10.1.4.2
Corp after R2 RIP
Corp#
show ip route
10.0.0.0/8 is variably subnetted, 10 subnets, 2 masks
C 10.1.1.0/24 is directly connected, Vlan1
L 10.1.1.1/32 is directly connected, Vlan1
C 10.1.2.0/24 is directly connected, Serial0/0/0
L 10.1.2.1/32 is directly connected, Serial0/0/0
C 10.1.3.0/24 is directly connected, Serial0/0/1
L 10.1.3.1/32 is directly connected, Serial0/0/1
C 10.1.4.0/24 is directly connected, Serial0/1/0
L 10.1.4.1/32 is directly connected, Serial0/1/0
C 10.1.5.0/24 is directly connected, FastEthernet0/0
L 10.1.5.1/32 is directly connected, FastEthernet0/0
172.16.0.0/24 is subnetted, 1 subnets
S 172.16.10.0/24 [150/0] via 10.1.5.2
R 192.168.10.0/24 [120/1] via 10.1.2.2, 00:00:19, Serial0/0/0
[120/1] via 10.1.3.2, 00:00:19, Serial0/0/1
R 192.168.20.0/24 [120/1] via 10.1.2.2, 00:00:19, Serial0/0/0
[120/1] via 10.1.3.2, 00:00:19, Serial0/0/1
from R1
R 192.168.30.0/24 [120/1] via 10.1.4.2, 00:00:15, Serial0/1/0
R 192.168.40.0/24 [120/1] via 10.1.4.2, 00:00:15, Serial0/1/0
from R2
RIP on R2 is advertising .30.0 and .40.0 to Corp
R1 before R2 RIP
R1#
show ip route
10.0.0.0/24 is subnetted, 5 subnets
R 10.1.1.0 [120/1] via 10.1.2.1, 00:00:05, Serial0/0/0
[120/1] via 10.1.3.1, 00:00:05, Serial0/0/1
from Corp
C 10.1.2.0 is directly connected, Serial0/0/0
C 10.1.3.0 is directly connected, Serial0/0/1
R 10.1.4.0 [120/1] via 10.1.2.1, 00:00:05, Serial0/0/0
[120/1] via 10.1.3.1, 00:00:05, Serial0/0/1
R 10.1.5.0 [120/1] via 10.1.2.1, 00:00:05, Serial0/0/0
[120/1] via 10.1.3.1, 00:00:05, Serial0/0/1
from Corp
172.16.0.0/24 is subnetted, 1 subnets
S 172.16.10.0 [150/0] via 10.1.3.1
C 192.168.10.0/24 is directly connected, FastEthernet0/0
C 192.168.20.0/24 is directly connected, FastEthernet0/1
S 192.168.30.0/24 [150/0] via 10.1.3.1
S 192.168.40.0/24 [150/0] via 10.1.2.1
R1 after R2 RIP
R1#
show ip route
10.0.0.0/24 is subnetted, 5 subnets
R 10.1.1.0 [120/1] via 10.1.2.1, 00:00:06, Serial0/0/0
[120/1] via 10.1.3.1, 00:00:06, Serial0/0/1
from Corp
C 10.1.2.0 is directly connected, Serial0/0/0
C 10.1.3.0 is directly connected, Serial0/0/1
R 10.1.4.0 [120/1] via 10.1.2.1, 00:00:06, Serial0/0/0
[120/1] via 10.1.3.1, 00:00:06, Serial0/0/1
R 10.1.5.0 [120/1] via 10.1.2.1, 00:00:06, Serial0/0/0
[120/1] via 10.1.3.1, 00:00:06, Serial0/0/1
from Corp
172.16.0.0/24 is subnetted, 1 subnets
S 172.16.10.0 [150/0] via 10.1.3.1
C 192.168.10.0/24 is directly connected, FastEthernet0/0
C 192.168.20.0/24 is directly connected, FastEthernet0/1
R 192.168.30.0/24 [120/2] via 10.1.3.1, 00:00:06, Serial0/0/1
[120/2] via 10.1.2.1, 00:00:06, Serial0/0/0
R 192.168.40.0/24 [120/2] via 10.1.2.1, 00:00:06, Serial0/0/0
[120/2] via 10.1.3.1, 00:00:06, Serial0/0/1
from R2 via Corp
Now to set RIP on R3
R3(config)#
router rip
R3(config-router)#
network 10.0.0.0
R3(config-router)#
network 172.16.0.0
note that R3 is our only router with "gateway of last resort" set because we set a default route instead of static routes
As a result, we only see directly connected routes listed, along with a single "S*" for the default gateway
R3 before RIP
R3#
show ip route
Gateway of last resort is 10.1.5.1 to network 0.0.0.0
10.0.0.0/8 is variably subnetted, 2 subnets, 2 masks
C 10.1.5.0/24 is directly connected, FastEthernet0/0
L 10.1.5.2/32 is directly connected, FastEthernet0/0
172.16.0.0/16 is variably subnetted, 2 subnets, 2 masks
C 172.16.10.0/24 is directly connected, Dot11Radio0/0/0
L 172.16.10.1/32 is directly connected, Dot11Radio0/0/0
S* 0.0.0.0/0 [1/0] via 10.1.5.1
R3 after RIP
R3#
show ip route
Gateway of last resort is 10.1.5.1 to network 0.0.0.0
-------------------------------------------------------------
10.0.0.0/8 is variably subnetted, 6 subnets, 2 masks
R 10.1.1.0/24 [120/1] via 10.1.5.1, 00:00:21, FastEthernet0/0
R 10.1.2.0/24 [120/1] via 10.1.5.1, 00:00:21, FastEthernet0/0
R 10.1.3.0/24 [120/1] via 10.1.5.1, 00:00:21, FastEthernet0/0
R 10.1.4.0/24 [120/1] via 10.1.5.1, 00:00:21, FastEthernet0/0
from Corp
C 10.1.5.0/24 is directly connected, FastEthernet0/0
L 10.1.5.2/32 is directly connected, FastEthernet0/0
-------------------------------------------------------------
172.16.0.0/16 is variably subnetted, 2 subnets, 2 masks
C 172.16.10.0/24 is directly connected, Dot11Radio0/0/0
L 172.16.10.1/32 is directly connected, Dot11Radio0/0/0
R 192.168.10.0/24 [120/2] via 10.1.5.1, 00:00:21, FastEthernet0/0
R 192.168.20.0/24 [120/2] via 10.1.5.1, 00:00:21, FastEthernet0/0
From R1 via Corp
R 192.168.30.0/24 [120/2] via 10.1.5.1, 00:00:21, FastEthernet0/0
R 192.168.40.0/24 [120/2] via 10.1.5.1, 00:00:21, FastEthernet0/0
From R2 via Corp
S* 0.0.0.0/0 [1/0] via 10.1.5.1
Corp before R3 RIP
Corp#
show ip route
10.0.0.0/8 is variably subnetted, 10 subnets, 2 masks
C 10.1.1.0/24 is directly connected, Vlan1
L 10.1.1.1/32 is directly connected, Vlan1
C 10.1.2.0/24 is directly connected, Serial0/0/0
L 10.1.2.1/32 is directly connected, Serial0/0/0
C 10.1.3.0/24 is directly connected, Serial0/0/1
L 10.1.3.1/32 is directly connected, Serial0/0/1
C 10.1.4.0/24 is directly connected, Serial0/1/0
L 10.1.4.1/32 is directly connected, Serial0/1/0
C 10.1.5.0/24 is directly connected, FastEthernet0/0
L 10.1.5.1/32 is directly connected, FastEthernet0/0
172.16.0.0/24 is subnetted, 1 subnets
S 172.16.10.0/24 [150/0] via 10.1.5.2
R 192.168.10.0/24 [120/1] via 10.1.2.2, 00:00:26, Serial0/0/0
[120/1] via 10.1.3.2, 00:00:26, Serial0/0/1
R 192.168.20.0/24 [120/1] via 10.1.2.2, 00:00:26, Serial0/0/0
[120/1] via 10.1.3.2, 00:00:26, Serial0/0/1
from R1 via corp
R 192.168.30.0/24 [120/1] via 10.1.4.2, 00:00:21, Serial0/1/0
R 192.168.40.0/24 [120/1] via 10.1.4.2, 00:00:21, Serial0/1/0
from R2 via corp
Corp after R3 RIP
Corp#
show ip route
10.0.0.0/8 is variably subnetted, 10 subnets, 2 masks
C 10.1.1.0/24 is directly connected, Vlan1
L 10.1.1.1/32 is directly connected, Vlan1
C 10.1.2.0/24 is directly connected, Serial0/0/0
L 10.1.2.1/32 is directly connected, Serial0/0/0
C 10.1.3.0/24 is directly connected, Serial0/0/1
L 10.1.3.1/32 is directly connected, Serial0/0/1
C 10.1.4.0/24 is directly connected, Serial0/1/0
L 10.1.4.1/32 is directly connected, Serial0/1/0
C 10.1.5.0/24 is directly connected, FastEthernet0/0
L 10.1.5.1/32 is directly connected, FastEthernet0/0
172.16.0.0/16 is variably subnetted, 2 subnets, 2 masks
R 172.16.0.0/16 [120/1] via 10.1.5.2, 00:00:13, FastEthernet0/0
S 172.16.10.0/24 [150/0] via 10.1.5.2
from R3
R 192.168.10.0/24 [120/1] via 10.1.3.2, 00:00:13, Serial0/0/1
[120/1] via 10.1.2.2, 00:00:13, Serial0/0/0
R 192.168.20.0/24 [120/1] via 10.1.3.2, 00:00:13, Serial0/0/1
[120/1] via 10.1.2.2, 00:00:13, Serial0/0/0
from R1 via corp
R 192.168.30.0/24 [120/1] via 10.1.4.2, 00:00:24, Serial0/1/0
R 192.168.40.0/24 [120/1] via 10.1.4.2, 00:00:24, Serial0/1/0
from R2 via corp
R2 before R3 RIP
R2#
show ip route
10.0.0.0/24 is subnetted, 5 subnets
R 10.1.1.0 [120/1] via 10.1.4.1, 00:00:15, Serial0/0/0
R 10.1.2.0 [120/1] via 10.1.4.1, 00:00:15, Serial0/0/0
R 10.1.3.0 [120/1] via 10.1.4.1, 00:00:15, Serial0/0/0
from Corp
C 10.1.4.0 is directly connected, Serial0/0/0
R 10.1.5.0 [120/1] via 10.1.4.1, 00:00:15, Serial0/0/0
from Corp
172.16.0.0/24 is subnetted, 1 subnets
S 172.16.10.0 [150/0] via 10.1.4.1
R 192.168.10.0/24 [120/2] via 10.1.4.1, 00:00:15, Serial0/0/0
R 192.168.20.0/24 [120/2] via 10.1.4.1, 00:00:15, Serial0/0/0
from R1 via Corp
C 192.168.30.0/24 is directly connected, FastEthernet0/0
C 192.168.40.0/24 is directly connected, FastEthernet0/1
R2 after R3 RIP
R2#
show ip route
10.0.0.0/24 is subnetted, 5 subnets
R 10.1.1.0 [120/1] via 10.1.4.1, 00:00:20, Serial0/0/0
R 10.1.2.0 [120/1] via 10.1.4.1, 00:00:20, Serial0/0/0
R 10.1.3.0 [120/1] via 10.1.4.1, 00:00:20, Serial0/0/0
from Corp
C 10.1.4.0 is directly connected, Serial0/0/0
R 10.1.5.0 [120/1] via 10.1.4.1, 00:00:20, Serial0/0/0
from Corp
172.16.0.0/16 is variably subnetted, 2 subnets, 2 masks
R 172.16.0.0/16 [120/2] via 10.1.4.1, 00:00:20, Serial0/0/0
S 172.16.10.0/24 [150/0] via 10.1.4.1
from R3 via Corp
R 192.168.10.0/24 [120/2] via 10.1.4.1, 00:00:20, Serial0/0/0
R 192.168.20.0/24 [120/2] via 10.1.4.1, 00:00:20, Serial0/0/0
from R1 via Corp
C 192.168.30.0/24 is directly connected, FastEthernet0/0
C 192.168.40.0/24 is directly connected, FastEthernet0/1
R1 before R3 RIP
R1#
show ip route
10.0.0.0/24 is subnetted, 5 subnets
R 10.1.1.0 [120/1] via 10.1.2.1, 00:00:04, Serial0/0/0
[120/1] via 10.1.3.1, 00:00:04, Serial0/0/1
C 10.1.2.0 is directly connected, Serial0/0/0
C 10.1.3.0 is directly connected, Serial0/0/1
R 10.1.4.0 [120/1] via 10.1.2.1, 00:00:04, Serial0/0/0
[120/1] via 10.1.3.1, 00:00:04, Serial0/0/1
R 10.1.5.0 [120/1] via 10.1.2.1, 00:00:04, Serial0/0/0
[120/1] via 10.1.3.1, 00:00:04, Serial0/0/1
from Corp
172.16.0.0/24 is subnetted, 1 subnets
S 172.16.10.0 [150/0] via 10.1.3.1
C 192.168.10.0/24 is directly connected, FastEthernet0/0
C 192.168.20.0/24 is directly connected, FastEthernet0/1
R 192.168.30.0/24 [120/2] via 10.1.2.1, 00:00:04, Serial0/0/0
[120/2] via 10.1.3.1, 00:00:04, Serial0/0/1
R 192.168.40.0/24 [120/2] via 10.1.2.1, 00:00:04, Serial0/0/0
[120/2] via 10.1.3.1, 00:00:04, Serial0/0/1
from R2 via Corp
R1 after R3 RIP
R1#
show ip route
10.0.0.0/24 is subnetted, 5 subnets
R 10.1.1.0 [120/1] via 10.1.3.1, 00:00:03, Serial0/0/1
[120/1] via 10.1.2.1, 00:00:03, Serial0/0/0
C 10.1.2.0 is directly connected, Serial0/0/0
C 10.1.3.0 is directly connected, Serial0/0/1
R 10.1.4.0 [120/1] via 10.1.3.1, 00:00:03, Serial0/0/1
[120/1] via 10.1.2.1, 00:00:03, Serial0/0/0
R 10.1.5.0 [120/1] via 10.1.3.1, 00:00:03, Serial0/0/1
[120/1] via 10.1.2.1, 00:00:03, Serial0/0/0
from Corp
172.16.0.0/16 is variably subnetted, 2 subnets, 2 masks
R 172.16.0.0/16 [120/2] via 10.1.3.1, 00:00:03, Serial0/0/1
[120/2] via 10.1.2.1, 00:00:03, Serial0/0/0
S 172.16.10.0/24 [150/0] via 10.1.3.1
from R3 via Corp
C 192.168.10.0/24 is directly connected, FastEthernet0/0
C 192.168.20.0/24 is directly connected, FastEthernet0/1
R 192.168.30.0/24 [120/2] via 10.1.3.1, 00:00:03, Serial0/0/1
[120/2] via 10.1.2.1, 00:00:03, Serial0/0/0
R 192.168.40.0/24 [120/2] via 10.1.3.1, 00:00:03, Serial0/0/1
[120/2] via 10.1.2.1, 00:00:03, Serial0/0/0
from R2 via Corp
Verifying Configurations
in addition to
show ip route
we can also use
show ip protocols
and
debug rip ip
Corp#
show ip protocols
Routing Protocol is "rip"
Sending updates every 30 seconds, next due in 11 seconds
Invalid after 180 seconds, hold down 180, flushed after 240
Outgoing update filter list for all interfaces is not set
Incoming update filter list for all interfaces is not set
Redistributing: rip
Default version control: send version 1, receive any version
Interface Send Recv Triggered RIP Key-chain
Vlan1 1 2 1
FastEthernet0/0 1 2 1
Serial0/0/1 1 2 1
Serial0/1/0 1 2 1
Serial0/0/0 1 2 1
Automatic network summarization is in effect
Maximum path: 4
Routing for Networks:
10.0.0.0
Passive Interface(s):
Routing Information Sources:
Gateway Distance Last Update
10.1.5.2 120 00:00:00
10.1.3.2 120 00:00:10
10.1.2.2 120 00:00:10
10.1.4.2 120 00:00:20
Distance: (default is 120)
R3#
debug ip rip
R3#RIP: received v1 update from 10.1.5.1 on FastEthernet0/0
10.1.1.0 in 1 hops
10.1.2.0 in 1 hops
10.1.3.0 in 1 hops
10.1.4.0 in 1 hops
192.168.10.0 in 2 hops
192.168.20.0 in 2 hops
192.168.30.0 in 2 hops
192.168.40.0 in 2 hops
R3#RIP: sending v1 update to 255.255.255.255 via Dot11Radio0/0/0 (172.16.10.1)
RIP: build update entries
network 10.0.0.0 metric 1
network 192.168.10.0 metric 3
network 192.168.20.0 metric 3
network 192.168.30.0 metric 3
network 192.168.40.0 metric 3
RIP: sending v1 update to 255.255.255.255 via FastEthernet0/0 (10.1.5.2)
RIP: build update entries
network 172.16.0.0 metric 1
output loops until manually disabled..............
R3#
undebug all
All possible debugging has been turned off
Note that due to the Split Horizon rule, R3 is not sending all of it's known RIP data to Corp.
It is sending all known RIP data out of the wifi interface (even there though there's no router that way),
but it is ONLY sending data about the wifi network back to Corp; data that Corp doesnt already have
Now lets look at some examples with sample routers..
I got hung up on these two examples because I found the
wording to be a bit confusing. Also there was subnetting involved that I was able to figure out, but threw me at first
First source of confusion- we have two seperate examples, and I was mixing them up.
The examples are:
Use the debug ip rip command to both:
discover a problem
and figure out how RIP was configured on a router from a different sample network
The conclusion regarding 'figuring out how RIP is configured' on this router, is that RIP networks are set as 10.0.0.0 and 172.16.0.0.
We determined that we are not the 'first source' of info on the 192.168.1.0 nertwork, since it is a metric of 2. We are sending out RIP data on that network,
but that RIP data is made availbale to us via another router.
I also got tripped up on the fact that RA is sending out S0/0 which corresponds 10.0.8.1,
and then receiving on the same interface S0/0 from an ip address of 10.0.15.0 on the other side of the link
I was able to determine that these two address are actually on the same subnet. My initial assumption was that the network address for the link is 10.0.0.0.
The problem doesn't give the subnet mask- I guessed it as /20 by using a 16 block since we can see that the third octet seems to move in 8's
if the network starts at 10.0.0.0 and we use /20 with 16 block, we would indeed have a last host address of 10.0.15.254, so 10.0.15.2 would be a valid host.
So there was a twist to this problem which needed subnetting to solve. It wasnt particulary releveant to the subject of RIP, but I was curious why the address on
the other side of that link looked so strange.
The problem also points out that we can determine there are 'at least' two routers participating in RIP here since we are sending RIP data out two interfaces but
only receiving RIP data on one interface. I'm unclear on why its worded this way; we know we are a RIP router- the fact that we are receiving data on one interface
would suggest there is 'at least one more' RIP router out there.
that's it for this example. Back to the original statement-
Use the debug ip rip command to both discover a problem and figure out
how RIP was configured on a router from a different sample network
We just 'figured out how RIP was configured on a router'.. The second example is regarding 'discovering a problem', although it is mentioned first.
The second example will use debug ip rip and show ip route to find a problem with the network
it looks like RIP data for 172.16.20.0 was received on S0/0, and then that interface was bumped out of the routing table entry for that network in favor of a static route.
ok, moving on now to RIP V2
RIP V2
enable it on all four routers
Corp(config)
router rip
Corp(config-router)
version 2
R1(config)
router rip
R1(config-router)
version 2
R2(config)
router rip
R2(config-router)
version 2
R3(config)
router rip
R3(config-router)
version 2
We'll use R1 to compare RIPv1 and RIPv2
RIPv1
R1(config)
debug ip rip
R1#RIP: sending v1 update to 255.255.255.255 via FastEthernet0/0 (192.168.10.1)
RIP: build update entries
network 10.0.0.0 metric 1
network 172.16.0.0 metric 3
network 192.168.20.0 metric 1
network 192.168.30.0 metric 3
network 192.168.40.0 metric 3
RIP: sending v1 update to 255.255.255.255 via FastEthernet0/1 (192.168.20.1)
RIP: build update entries
network 10.0.0.0 metric 1
network 172.16.0.0 metric 3
network 192.168.10.0 metric 1
network 192.168.30.0 metric 3
network 192.168.40.0 metric 3
RIP: sending v1 update to 255.255.255.255 via Serial0/0/0 (10.1.2.2)
RIP: build update entries
network 10.1.3.0 metric 1
network 192.168.10.0 metric 1
network 192.168.20.0 metric 1
RIP: sending v1 update to 255.255.255.255 via Serial0/0/1 (10.1.3.2)
RIP: build update entries
network 10.1.2.0 metric 1
network 192.168.10.0 metric 1
network 192.168.20.0 metric 1
RIPv2
R1(config)
debug ip rip
R1#RIP: sending v2 update to 224.0.0.9 via FastEthernet0/0 (192.168.10.1)
RIP: build update entries
10.0.0.0/8 via 0.0.0.0, metric 1, tag 0
172.16.0.0/16 via 0.0.0.0, metric 3, tag 0
192.168.20.0/24 via 0.0.0.0, metric 1, tag 0
192.168.30.0/24 via 0.0.0.0, metric 3, tag 0
192.168.40.0/24 via 0.0.0.0, metric 3, tag 0
RIP: sending v2 update to 224.0.0.9 via FastEthernet0/1 (192.168.20.1)
RIP: build update entries
10.0.0.0/8 via 0.0.0.0, metric 1, tag 0
172.16.0.0/16 via 0.0.0.0, metric 3, tag 0
192.168.10.0/24 via 0.0.0.0, metric 1, tag 0
192.168.30.0/24 via 0.0.0.0, metric 3, tag 0
192.168.40.0/24 via 0.0.0.0, metric 3, tag 0
RIP: sending v2 update to 224.0.0.9 via Serial0/0/0 (10.1.2.2)
RIP: build update entries
10.1.3.0/24 via 0.0.0.0, metric 1, tag 0
192.168.10.0/24 via 0.0.0.0, metric 1, tag 0
192.168.20.0/24 via 0.0.0.0, metric 1, tag 0
RIP: sending v2 update to 224.0.0.9 via Serial0/0/1 (10.1.3.2)
RIP: build update entries
10.1.2.0/24 via 0.0.0.0, metric 1, tag 0
192.168.10.0/24 via 0.0.0.0, metric 1, tag 0
192.168.20.0/24 via 0.0.0.0, metric 1, tag 0
R1(config)
show ip protocols
Routing Protocol is "rip"
Sending updates every 30 seconds, next due in 13 seconds
Invalid after 180 seconds, hold down 180, flushed after 240
Outgoing update filter list for all interfaces is not set
Incoming update filter list for all interfaces is not set
Redistributing: rip
Default version control: send version 2, receive 2
Interface Send Recv Triggered RIP Key-chain
FastEthernet0/0 2 2
FastEthernet0/1 2 2
Serial0/0/0 2 2
Serial0/0/1 2 2
Automatic network summarization is in effect
Maximum path: 4
Routing for Networks:
10.0.0.0
192.168.10.0
192.168.20.0
Passive Interface(s):
Routing Information Sources:
Gateway Distance Last Update
10.1.3.1 120 00:00:21
10.1.2.1 120 00:00:21
Distance: (default is 120)
final task of this chapter
Enable a default route out to the internet , and advertise via RIP
R3(config)#
interface s0/1/0 (this is only for example, so I am not adding a serial card to R3)
R3(config-if)#
ip addr 172.16.10.5 255.255.255.252
R3(config-if)#
exit
R3(config)#
ip route 0.0.0.0 0.0.0.0 s0/0
R3(config)#
ip default-network 172.16.0.0 tells other routers via RIP that default WAN route is through R3
Chapter 8 Exam Essentials IP Routing
1. Describe the Basic IP routing process
frame changes at each hop, but packet doesnt change EXCEPT that the TTL field in the IP header decrements
2. List the information required by a router to successfully route packets
destination IP address, location of other routers, possible routers to all remote networks,
the best route to each network, how to maintain and maintain routing info
3. Describe how MAC addresses are used during the routing process
a MAC will never pass a router interface. MACs will change between router interfaces
4. View and interpret the routing table of a router
use show ip route to see the table
a "C" indicates directly connected, an "R" indicates RIP provided the route info, "S" means static
5. differentiate the three types of routing
static- manually configured
dynamic- routers automatically share info via protocol
default- a special route is configured for all traffic without a more specific destination network found in the table
6. Compare and contrast static and dynamic routing
static routing creates no routing update traffic which means less overhead on the routers and links- but it must be
configured manually and can't react if links are lost.
dynamic routing creates update traffic, but it can react to outages and choose the best route when multiple routes exist to the same network
7. Configure static routes at the CLI
route [dest network] [mask] [next hop address OR exit interface] [admin distance] [permanent]
Ex:
Corp(config)#
ip route 192.168.10.0 255.255.255.0 10.1.2.2 150
8. Create a default route
ip route 0.0.0.0 0.0.0.0 [ip address OR exit interface]
Ex:
R3(config)#
ip route 0.0.0.0 0.0.0.0 10.1.5.1 (ingress at Corp router- use if R3 cant identify route)
9. Understand administrative distance and its role in the selection of the best route
an integer from 0 (most trusted) to 255 (no traffic will pass via this route).
All routing protocols are assigned an AD but it can be changed at the CLI
10. Differentiate distance-vector, link-state, and hybrid routing protocols
distance vector- based on hop count (RIP)
link-state- multiple factors such as bandwidth and delay
hybrid- uses both
11. List mechanisms used to prevent routing loops in the network
max hop count, split horizon, route poisoning, holddown counters
12. Describe the counts used the operation of RIP
route update timer- (30) interval between routing updates
route invalid timer- (180, update x 3) before a route is determined invalid
holddown timer-(180) time info is supressed when a link is lost
route flush timer- (240) seconds before invalid and removal
13. Configure RIP routing
router rip
network x.x.x.x
the network(s) you want to advertise from your router. It only works if the other router has RIP enabled.
By enabling RIP, you are able to RECEIVE RIP data from other RIP routers.
by specifying a network, you are SENDING RIP data on that network
14. Identify commands used to verify RIP routing
show ip route will provide contents of the routing table with codes (R, C, S)
debug ip rip will show RIP updates being sent and received
15. Describe the differences between RIPv1 and RIPv2
RIPv1 sends a broadcast (255.255.255.255) every 30 seconds and has an AD of 120.
RIPv1 is classful only, does not send any mask info. No authentication between routers.
RIPv2 sends multicasts (224.0.0.9) every 30 seconds and sends mask info, which allows it to support classless networking, RIPv2 also supports
autentication between routers.
Chapter 8 Written Lab 8.0
1. At the appropriate prompt, create a static route to network 172.16.10.0/24 with a next-hop
gateway of 172.16.20.1 and an administrative distance of 150.
Router(config)#
ip route 172.16.10.0 255.255.255.0 172.16.20.1 150
2. When a PC sends a packet to another PC in a remote network, what destination IP address and MAC address will
be in the frame that it sends to it's default gateway?
the gateway interface MAC and the remote PC's IP
3. At the appropriate prompt, create a default route to 172.16.40.1
Router(config)#
ip route 0.0.0.0 0.0.0.0 172.16.40.1
"to" is the wrong word.. we are going TO any route VIA 172.16.40.1
4. If you are using default routing in a classless environment, what command must also be used?
Router(config)#
ip classless
5. On which type of network is a default route most beneficial?
stub
6. At the appropriate prompt, display the routing table on your router
Router#
show ip route
7. When creating a static or default route, you dont have to use the next-hop ip address;
you can instead use the ____________
exit interface
8. True/False: To reach a destination host, you must know the MAC address of the remote host
false, you need the MAC of your router
9. True/False: To reach a destination host, you must know the IP address of the remote host
true
10. At the appropriate prompt, execute the command required on a DCE serial interface that is not required
on a DTE serial interface
Router(config-if)#
clock rate X
11. At the appropriate prompt, enable RIP routing on the interface with the IP address 10.0.0.1/24
Router(config)#
router rip
Router(config-router)#
network 10.0.0.0
RIPv1 is CLASSFUL only... use the classful mask based on the first octet given
12. At the appropriate prompt, prevent a router from propagating IP information out serial 1
Router(config)#
router rip
Router(config-router)#
passive-interface S0/1
can receive RIP data but will not send
13. What routing loop prevention mechanism sends out a maximum hop count as soon as a link fails?
route poisoning
14. What routing loop prevention mechanism suppresses the resending of routing information to an interface
through which it was received?
split horizon
15. At the appropriate prompt display RIP routing updates as they are sent and received on the router
to the console session
Router#
debug ip rip
to turn it off:
Router#
undebug all
Chapter 8 Hands-on Labs
For these labs we will need a network with three routers.
Lab 8.1 Creating Static routes
first set the interfaces, then program the static routes
LabA(config)#
int s0/0/0
LabA(config-if)#
ip addr 172.16.20.1
LabA(config-if)#
int f0/0
LabA(config-if)#
ip addr 172.16.10.1
-----------------------------------------------------------------
LabA(config)#
ip route 172.16.30.0 255.255.255.0 172.16.20.2
LabA(config)#
ip route 172.16.40.0 255.255.255.0 172.16.20.2
LabB(config)#
int s0/0/0
LabB(config-if)#
ip addr 172.16.20.2
LabB(config-if)#
int s0/0/1
LabB(config-if)#
ip addr 172.16.30.1
-----------------------------------------------------------------
LabB(config)#
ip route 172.16.10.0 255.255.255.0 172.16.20.1
LabB(config)#
ip route 172.16.40.0 255.255.255.0 172.16.30.2
LabC(config)#
int s0/0/0
LabC(config-if)#
ip addr 172.16.30.2
LabC(config-if)#
int f0/0
LabC(config-if)#
ip addr 172.16.40.1
-----------------------------------------------------------------
LabC(config)#
ip route 172.16.10.0 255.255.255.0 172.16.30.1
LabC(config)#
ip route 172.16.20.0 255.255.255.0 172.16.30.1
Lab 8.2 RIP Configuration
remove the static routes, enable and configure RIP with the classful network id that covers the routes you want to advertise
LabA(config)#
no ip route 172.16.30.0 255.255.255.0 172.16.20.2
LabA(config)#
no ip route 172.16.40.0 255.255.255.0 172.16.20.2
LabA(config)#
router rip
LabA(config-router)#
network 172.16.0.0
LabA(config-router)#
do show ip route
Gateway of last resort is not set
172.16.0.0/16 is variably subnetted, 5 subnets, 2 masks
C 172.16.10.0/24 is directly connected, FastEthernet0/0
L 172.16.10.1/32 is directly connected, FastEthernet0/0
C 172.16.20.0/24 is directly connected, Serial0/0/0
L 172.16.20.1/32 is directly connected, Serial0/0/0
R 172.16.30.0/24 [120/1] via 172.16.20.2, 00:00:07, Serial0/0/0
from Lab B
LabB(config)#
no ip route 172.16.10.0 255.255.255.0 172.16.20.1
LabB(config)#
no ip route 172.16.40.0 255.255.255.0 172.16.30.2
LabB(config)#
router rip
LabB(config-router)#
network 172.16.0.0
LabB(config-router)#
do show ip route
Gateway of last resort is not set
172.16.0.0/16 is variably subnetted, 5 subnets, 2 masks
R 172.16.10.0/24 [120/1] via 172.16.20.1, 00:00:13, Serial0/0/0
from LabA
C 172.16.20.0/24 is directly connected, Serial0/0/0
L 172.16.20.2/32 is directly connected, Serial0/0/0
C 172.16.30.0/24 is directly connected, Serial0/0/1
L 172.16.30.1/32 is directly connected, Serial0/0/1
LabC(config)#
no ip route 172.16.10.0 255.255.255.0 172.16.30.1
LabC(config)#
no ip route 172.16.20.0 255.255.255.0 172.16.30.1
LabC(config)#
router rip
LabC(config-router)#
network 172.16.0.0
LabC(config-router)#
do show ip route
Gateway of last resort is not set
172.16.0.0/16 is variably subnetted, 3 subnets, 2 masks
R 172.16.20.0/24 [120/1] via 172.16.30.1, 00:00:05, Serial0/0/0
from LabB
C 172.16.30.0/24 is directly connected, Serial0/0/0
L 172.16.30.2/32 is directly connected, Serial0/0/0
Chapter 8 Review Questions
1. The Acme company uses a router named Gateway to connect to its ISP. The address of the ISP router is 206.143.5.2.
Which three commands could be configured on the gateway router to allow internet access to the entire network?
Set a default route:
Gateway(config)#
ip route 0.0.0.0 0.0.0.0 206.143.5.2 next hop IP
Gateway(config)#
ip route 0.0.0.0 0.0.0.0 S/0 exit interface instead of next hop IP
Gateway(config)#
ip default-network 206.143.5.0 next hop IP
2. What command will prevent RIP routing updates from exiting an interface but will sill allow the interface to receive RIP updates?
Router(config-if)#
passive-interface
3. Which two statemnts are true about ip route 172.16.4.0 255.255.255.0 192.168.4.2?
the command establishes a static route
the default admin distance is used (since we didnt give an AD argument)
4. What two destination addresses will be used by HostA to send data to the HTTPS server as shown in the following network?
MAC of RouterA f0/0 interface
IP address of the server
5. Which two statements are true about this output?
RIP: received v1 update from 192.168.40.2 on S0/1
192.168.50.0 in 16 hops (inaccessible)
RIP: sending v1 update to 255.255.255.255 via F0/0 (192.168.30.1)
RIP: build update entries
network 192.168.20.0 metric 1
network 192.168.40.0 metric 1
network 192.168.50.0 metric 16
RIP: sending v1 update to 255.255.255.255 via S0/1 (192.168.40.1)
true:
there are at least two routers exchanging information
192.168.40.2 will be successful
FALSE
there are three interfaces on the router participating in this update
false because we only see two interfaces represented in the output: S0/1(twice) and F0/0
a ping to 192.168.50.1 will be successful
false because that route has a metric of 16; it's unreachable
6. Describe split horizon
will not advertise a route back the the same router it was learned from
7. Which would be true if HostA is trying to communicate to HostB and interface F0/0 of RouterC goes down, as shown in the graphic?
RouterC will send an ICMP 'destination unreachable type' message to inform HostA that HostB is unreachable
8. Which two statements are true regarding classless routing protocols?
VLSM is permitted
RIPv2 supports classless
9. Which two are true regarding distance-vector vs link-state?
Distance vector sends the whole routing table out all active interfaces(even if a router isnt on the other end)at periodic time intervals
Link-state sends updates containing the state of its own links to all routers in the inter-network
10. Which command display RIP routing updates?
debug ip rip
11. What does RIPv2 use to prvent routing loops?
split horizon stops an update from being send on the same interface it was received
holdown timers allow time for a network to become stable in the case of a flapping link
12. A network administrator views the output from the show ip route command. A network that is advertised
by both RIP and EIGRP appears in the routing table flagged an EIGRP route. Why is the RIP route to this network not used in this routing table?
EIGRP has a lower AD.
RIP=120
OSPP=110
IGRP=110
EIGRP=90
13. You type debug ip rip on your router console and see that 172.16.10.0 is being advertised to you with a metric of 16. What does this mean?
it is inaccessible. in RIP if you see a route advertised with a metric of 16, it's inaccessible
14. What metric does RIPv2 use to find the best path to the remote network?
distance aka hop count
15. The Corporate router receives an IP packet with a source IP address of 192.168.214.20 and a destination address of 192.168.22.3. Looking at the output from the Corp router,
what will the router do with this packet?
Corp# show ip route
[cut]
R 192.168.215.0 [120/2] via 192.168.20.2, Serail0/0
R 192.168.115.0 [120/1] via 192.168.20.0, Serial0/0
R 192.168.30.0 [120/1] via 192.168.20.2, Serial0/0
C 192.168.20.0 is directly connected, Serial0/0
C 192.168.214.0 is directly connected, FastEthernet0/0
Since there is no route to that network, the router will discard the packet and send an ICMP destination unreachable message out F0/0 back the the source network
16. If your routing table has a static, a RIP and an EIGRP route to the same network, which route will be used by default?
Static routes have an admin distance of 1 by default. Unless you change it, a static route will always be used over any other
dynamically learned route.
17. You have the following routing table. Which network will NOT be placed in the neighbor routing table?
R 192.168.30.0/24 [120/1] via 192.168.40.1, Serial 0
C 192.168.40.0/24 is directly connected, Serial 0
172.16.0.0/2 is subnetted, 1 subnets
C 172.16.30.0 is directly connected, Loopback0
R 192.168.20.0/24 [120/1] via 192.168.40.1, Serial 0
R 10.0.0.0/8 [120/15] via 192.168.40.1, Serial 0
C 192.168.50.0/24 is directly connected, Ethernet 0
10.0.0.0 cant be placed in neighboring routing table because it is at 15 hops. 16 hops is invalid in RIP
18. Two connected routers are configured only with RIP. What will be the result when a router receives a routing update that contains a
higher-cost path to a network already in it's routing table?
The router will ignore the update because it is higher cost. When a routing update is received, the router first checks the AD and always chooses
the route with the lowest AD.
19.Which is true about route poisoning?
The router sets the metric for a downed link to "infinity".
20. Which is true about RIPv2?
it has all the same timers as RIPv1
------------------------------------------------------------------------------
END CHAPTER 8
54 hours 1-28 thru 2-14-22
original total 143 hours
11.5 hours review 12-23,24,26-22
review total hours 32
book page 428/822
avg 20 min/page (reading and exercises/labs)
Chapter 9 EIGRP and OSPF
pages 427-502, start 2-14-22-M
What is EIGRP?
Note it's not officially on CCNA 200-301 but it is still important to learn
Enhanced IGRP is a classless, enchanced distance vector protocol that uses the concept of an autonomous system to describe
the set of contigous routers that run the same routing protocol and share routing information.
Features:
Support for IP and IPv6 via protocol-dependent modules (seperate routing tables)
Considered classless
Support for summaries and discontiguous networks
Eficient neighbor discovery
communication via RTP- Reliable Transport Protocol
best path selection via Diffusing Updae Algorithm DUAL
Cisco considers EIGRP a "distance-vector" routing protocol
or an "advanced distance-vector" protocol
or a "hybrid" protocol
Configuring EIGRP on our network
------------------------------------------------------------------------------------------------------------------------------------
Corp(config)#
router eigrp ?
<1-65535> Autonomous system number
Corp(config)#
router eigrp 10
R2(config-router)#
network 10.0.0.0
after eigrp on R1- links from Corp to R1 are up
%DUAL-5-NBRCHANGE: IP-EIGRP 10: Neighbor 10.1.3.2 (Serial0/0/1) is up: new adjacency
%DUAL-5-NBRCHANGE: IP-EIGRP 10: Neighbor 10.1.2.2 (Serial0/0/0) is up: new adjacency
after eigrp on R2- link from Corp to R2 is up
%DUAL-5-NBRCHANGE: IP-EIGRP 10: Neighbor 10.1.4.2 (Serial0/1/0) is up: new adjacency
after eigrp on R3- link from Corp to R3 is up
%DUAL-5-NBRCHANGE: IP-EIGRP 10: Neighbor 10.1.5.2 (FastEthernet0/0) is up: new adjacency
------------------------------------------------------------------------------------------------------------------------------------
R1(config)#
router eigrp 10
R1(config-router)#
network 10.0.0.0
after eigrp on R1- link from R1 to Corp is up
%DUAL-5-NBRCHANGE: IP-EIGRP 10: Neighbor 10.1.3.1 (Serial0/0/1) is up: new adjacency
%DUAL-5-NBRCHANGE: IP-EIGRP 10: Neighbor 10.1.2.1 (Serial0/0/0) is up: new adjacency
R1(config-router)#
network 192.168.10.0
R1(config-router)#
network 192.168.20.0
------------------------------------------------------------------------------------------------------------------------------------
R2(config)#
router eigrp 10
R2(config-router)#
network 10.0.0.0
after eigrp on R2- link from R2 to Corp is up
%DUAL-5-NBRCHANGE: IP-EIGRP 10: Neighbor 10.1.4.1 (Serial0/0/0) is up: new adjacency
R1(config-router)#
network 192.168.30.0
R1(config-router)#
network 192.168.40.0
------------------------------------------------------------------------------------------------------------------------------------
R3(config)#
router eigrp 10
R3(config-router)#
network 10.0.0.0
after eigrp on R3- link from R3 to Corp is up
%DUAL-5-NBRCHANGE: IP-EIGRP 10: Neighbor 10.1.5.1 (FastEthernet0/0) is up: new adjacency
R1(config-router)#
network 172.16.0.0
------------------------------------------------------------------------------------------------------------------------------------
Corp#
show ip route
Gateway of last resort is not set
Gateway of last resort is not set
10.0.0.0/8 is variably subnetted, 10 subnets, 2 masks
C 10.1.1.0/24 is directly connected, Vlan1
L 10.1.1.1/32 is directly connected, Vlan1
C 10.1.2.0/24 is directly connected, Serial0/0/0
L 10.1.2.1/32 is directly connected, Serial0/0/0
C 10.1.3.0/24 is directly connected, Serial0/0/1
L 10.1.3.1/32 is directly connected, Serial0/0/1
C 10.1.4.0/24 is directly connected, Serial0/1/0
L 10.1.4.1/32 is directly connected, Serial0/1/0
C 10.1.5.0/24 is directly connected, FastEthernet0/0
L 10.1.5.1/32 is directly connected, FastEthernet0/0
172.16.0.0/16 is variably subnetted, 2 subnets, 2 masks
R 172.16.0.0/16 [120/1] via 10.1.5.2, 00:00:17, FastEthernet0/0
D 172.16.10.0/24 [90/28160] via 10.1.5.2, 00:00:16, FastEthernet0/0
via R3
D 192.168.10.0/24 [90/2172416] via 10.1.2.2, 00:19:13, Serial0/0/0
[90/2172416] via 10.1.3.2, 00:19:13, Serial0/0/1
D 192.168.20.0/24 [90/2172416] via 10.1.3.2, 00:19:05, Serial0/0/1
[90/2172416] via 10.1.2.2, 00:19:05, Serial0/0/0
via R1
D 192.168.30.0/24 [90/2172416] via 10.1.4.2, 00:01:31, Serial0/1/0
D 192.168.40.0/24 [90/2172416] via 10.1.4.2, 00:01:08, Serial0/1/0
via R2
The "D" routes are for DUAL- Diffusing Update Algorithm, indicating they are EIGRP routes.
Note that we have RIP and EIGRP set currently
------------------------------------------------------------------------------------------------------------------------------------
R1#
show ip route
Gateway of last resort is not set
10.0.0.0/8 is variably subnetted, 6 subnets, 2 masks
D 10.0.0.0/8 is a summary, 00:25:28, Null0
D 10.1.1.0/24 [90/27769856] via 10.1.2.1, 00:31:33, Serial0/0/0
[90/27769856] via 10.1.3.1, 00:31:30, Serial0/0/1
via Corp
C 10.1.2.0/24 is directly connected, Serial0/0/0
C 10.1.3.0/24 is directly connected, Serial0/0/1
D 10.1.4.0/24 [90/2681856] via 10.1.2.1, 00:31:33, Serial0/0/0
[90/2681856] via 10.1.3.1, 00:31:30, Serial0/0/1
D 10.1.5.0/24 [90/2172416] via 10.1.2.1, 00:31:33, Serial0/0/0
[90/2172416] via 10.1.3.1, 00:31:30, Serial0/0/1
via Corp
172.16.0.0/16 is variably subnetted, 2 subnets, 2 masks
R 172.16.0.0/16 [120/2] via 10.1.2.1, 00:00:07, Serial0/0/0
[120/2] via 10.1.3.1, 00:00:07, Serial0/0/1
D 172.16.10.0/24 [90/2172416] via 10.1.2.1, 00:06:31, Serial0/0/0
[90/2172416] via 10.1.3.1, 00:06:31, Serial0/0/1
via Corp
C 192.168.10.0/24 is directly connected, FastEthernet0/0
C 192.168.20.0/24 is directly connected, FastEthernet0/1
D 192.168.30.0/24 [90/2684416] via 10.1.3.1, 00:07:46, Serial0/0/1
[90/2684416] via 10.1.2.1, 00:07:46, Serial0/0/0
D 192.168.40.0/24 [90/2684416] via 10.1.2.1, 00:07:23, Serial0/0/0
[90/2684416] via 10.1.3.1, 00:07:23, Serial0/0/1
via Corp
------------------------------------------------------------------------------------------------------------------------------------
R2#
show ip route
Gateway of last resort is not set
10.0.0.0/8 is variably subnetted, 6 subnets, 2 masks
D 10.0.0.0/8 is a summary, 00:13:09, Null0
D 10.1.1.0/24 [90/27769856] via 10.1.4.1, 00:36:53, Serial0/0/0
D 10.1.2.0/24 [90/2681856] via 10.1.4.1, 00:36:53, Serial0/0/0
D 10.1.3.0/24 [90/2681856] via 10.1.4.1, 00:36:53, Serial0/0/0
via Corp
C 10.1.4.0/24 is directly connected, Serial0/0/0
D 10.1.5.0/24 [90/2172416] via 10.1.4.1, 00:36:53, Serial0/0/0
via Corp
172.16.0.0/16 is variably subnetted, 2 subnets, 2 masks
R 172.16.0.0/16 [120/2] via 10.1.4.1, 00:00:23, Serial0/0/0
D 172.16.10.0/24 [90/2172416] via 10.1.4.1, 00:11:54, Serial0/0/0
via Corp
D 192.168.10.0/24 [90/2684416] via 10.1.4.1, 00:30:51, Serial0/0/0
D 192.168.20.0/24 [90/2684416] via 10.1.4.1, 00:30:43, Serial0/0/0
via Corp
C 192.168.30.0/24 is directly connected, FastEthernet0/0
C 192.168.40.0/24 is directly connected, FastEthernet0/1
------------------------------------------------------------------------------------------------------------------------------------
R3#
show ip route
Gateway of last resort is 10.1.5.1 to network 0.0.0.0
10.0.0.0/8 is variably subnetted, 6 subnets, 2 masks
D 10.1.1.0/24 [90/25628160] via 10.1.5.1, 00:37:20, FastEthernet0/0
D 10.1.2.0/24 [90/2172416] via 10.1.5.1, 00:37:15, FastEthernet0/0
D 10.1.3.0/24 [90/2172416] via 10.1.5.1, 00:37:20, FastEthernet0/0
D 10.1.4.0/24 [90/2172416] via 10.1.5.1, 00:37:20, FastEthernet0/0
via Corp
C 10.1.5.0/24 is directly connected, FastEthernet0/0
L 10.1.5.2/32 is directly connected, FastEthernet0/0
172.16.0.0/16 is variably subnetted, 2 subnets, 2 masks
C 172.16.10.0/24 is directly connected, Dot11Radio0/0/0
L 172.16.10.1/32 is directly connected, Dot11Radio0/0/0
D 192.168.10.0/24 [90/2174976] via 10.1.5.1, 00:31:10, FastEthernet0/0
D 192.168.20.0/24 [90/2174976] via 10.1.5.1, 00:31:02, FastEthernet0/0
via Corp and R1
D 192.168.30.0/24 [90/2174976] via 10.1.5.1, 00:13:28, FastEthernet0/0
D 192.168.40.0/24 [90/2174976] via 10.1.5.1, 00:13:05, FastEthernet0/0
via Corp and R2
S* 0.0.0.0/0 [1/0] via 10.1.5.1
------------------------------------------------------------------------------------------------------------------------------------
turn off auto summary on each router
------------------------------------------------------------------------------------------------------------------------------------
Corp(config)#
router eigrp 10
Corp(config-router)#
no auto-summary
------------------------------------------------------------------------------------------------------------------------------------
R1(config)#
router eigrp 10
R1(config-router)#
no auto-summary
------------------------------------------------------------------------------------------------------------------------------------
R2(config)#
router eigrp 10
R2(config-router)#
no auto-summary
------------------------------------------------------------------------------------------------------------------------------------
R3(config)#
router eigrp 10
R3(config-router)#
no auto-summary
------------------------------------------------------------------------------------------------------------------------------------
compare Corp before and after auto summary turned off
------------------------------------------------------------------------------------------------------------------------------------
auto summary on
Corp#
show ip route
Gateway of last resort is not set
10.0.0.0/8 is variably subnetted, 10 subnets, 2 masks
C 10.1.1.0/24 is directly connected, Vlan1
L 10.1.1.1/32 is directly connected, Vlan1
C 10.1.2.0/24 is directly connected, Serial0/0/0
L 10.1.2.1/32 is directly connected, Serial0/0/0
C 10.1.3.0/24 is directly connected, Serial0/0/1
L 10.1.3.1/32 is directly connected, Serial0/0/1
C 10.1.4.0/24 is directly connected, Serial0/1/0
L 10.1.4.1/32 is directly connected, Serial0/1/0
C 10.1.5.0/24 is directly connected, FastEthernet0/0
L 10.1.5.1/32 is directly connected, FastEthernet0/0
172.16.0.0/16 is variably subnetted, 2 subnets, 2 masks
R 172.16.0.0/16 [120/1] via 10.1.5.2, 00:00:17, FastEthernet0/0
D 172.16.10.0/24 [90/28160] via 10.1.5.2, 00:00:16, FastEthernet0/0
via R3
D 192.168.10.0/24 [90/2172416] via 10.1.2.2, 00:19:13, Serial0/0/0
[90/2172416] via 10.1.3.2, 00:19:13, Serial0/0/1
D 192.168.20.0/24 [90/2172416] via 10.1.3.2, 00:19:05, Serial0/0/1
[90/2172416] via 10.1.2.2, 00:19:05, Serial0/0/0
via R1
D 192.168.30.0/24 [90/2172416] via 10.1.4.2, 00:01:31, Serial0/1/0
D 192.168.40.0/24 [90/2172416] via 10.1.4.2, 00:01:08, Serial0/1/0
via R2
auto summary off
Corp#
show ip route
Gateway of last resort is not set
10.0.0.0/8 is variably subnetted, 10 subnets, 2 masks
C 10.1.1.0/24 is directly connected, Vlan1
L 10.1.1.1/32 is directly connected, Vlan1
C 10.1.2.0/24 is directly connected, Serial0/0/0
L 10.1.2.1/32 is directly connected, Serial0/0/0
C 10.1.3.0/24 is directly connected, Serial0/0/1
L 10.1.3.1/32 is directly connected, Serial0/0/1
C 10.1.4.0/24 is directly connected, Serial0/1/0
L 10.1.4.1/32 is directly connected, Serial0/1/0
C 10.1.5.0/24 is directly connected, FastEthernet0/0
L 10.1.5.1/32 is directly connected, FastEthernet0/0
172.16.0.0/16 is variably subnetted, 2 subnets, 2 masks
R 172.16.0.0/16 [120/1] via 10.1.5.2, 00:00:12, FastEthernet0/0
D 172.16.10.0/24 [90/28160] via 10.1.5.2, 00:45:29, FastEthernet0/0
via R3
D 192.168.10.0/24 [90/2172416] via 10.1.2.2, 00:01:08, Serial0/0/0
[90/2172416] via 10.1.3.2, 00:01:08, Serial0/0/1
D 192.168.20.0/24 [90/2172416] via 10.1.2.2, 00:01:08, Serial0/0/0
[90/2172416] via 10.1.3.2, 00:01:08, Serial0/0/1
via R1
D 192.168.30.0/24 [90/2172416] via 10.1.4.2, 00:00:46, Serial0/1/0
D 192.168.40.0/24 [90/2172416] via 10.1.4.2, 00:00:46, Serial0/1/0
via R2
We are still seeing an auto summarized route- 172.16.0.0 coming from R3.
The book discusses enabling EIGRP auto summary on all four routers- nothing is said about disabling it within RIP or turning off RIP.
RIP auto summarizes by default. We cant get rid of this auto summary route while RIP is on.
Moving on...
VERIFYING EIGRP
several commands available to verify and troubleshoot
show ip route
show the entire routing table
show ip route eigrp
show only EIGRP entries in the routing table
show ip eigrp neighbors
show all EIGRP neigbors
show ip eigrp topology
show entries in the EIGRP topology table
show ip protocols
shows routing protocols configuration
debug eigrp packet
shows hello packets sent/received between adjacent routers
debug ip eigrp events
shows EIGRP changes and updates as they occur on your network
lets take a look at the state of our 4 routers. RIP and EIGRP are running on each.
Notice how this command is giving different outputs between the two different IOS versions
IOS 15.1
Corp#
show ip protocols
Routing Protocol is "eigrp 10 "
Outgoing update filter list for all interfaces is not set
Incoming update filter list for all interfaces is not set
Default networks flagged in outgoing updates
Default networks accepted from incoming updates
Redistributing: eigrp 10
EIGRP-IPv4 Protocol for AS(10)
Metric weight K1=1, K2=0, K3=1, K4=0, K5=0
NSF-aware route hold timer is 240
Router-ID: 10.1.1.1
Topology : 0 (base)
Active Timer: 3 min
Distance: internal 90 external 170
Maximum path: 4
Maximum hopcount 100
Maximum metric variance 1
Automatic Summarization: disabled
Automatic address summarization:
Maximum path: 4
Routing for Networks:
10.0.0.0
Routing Information Sources:
Gateway Distance Last Update
10.1.5.2 90 0
10.1.3.2 90 6464
10.1.2.2 90 6795
10.1.4.2 90 7955
Distance: internal 90 external 170
Routing Protocol is "rip"
Sending updates every 30 seconds, next due in 10 seconds
Invalid after 180 seconds, hold down 180, flushed after 240
Outgoing update filter list for all interfaces is not set
Incoming update filter list for all interfaces is not set
Redistributing: rip
Default version control: send version 2, receive 2
Interface Send Recv Triggered RIP Key-chain
Vlan1 2 2
FastEthernet0/0 2 2
Serial0/1/0 2 2
Serial0/0/1 2 2
Serial0/0/0 2 2
Automatic network summarization is in effect
Maximum path: 4
Routing for Networks:
10.0.0.0
Passive Interface(s):
Routing Information Sources:
Gateway Distance Last Update
10.1.5.2 120 00:00:12
10.1.3.2 120 00:00:16
10.1.2.2 120 00:00:16
10.1.4.2 120 00:00:13
Distance: (default is 120)
IOS 12.4
R1#
show ip protocols
Routing Protocol is "eigrp 10 "
Outgoing update filter list for all interfaces is not set
Incoming update filter list for all interfaces is not set
Default networks flagged in outgoing updates
Default networks accepted from incoming updates
EIGRP metric weight K1=1, K2=0, K3=1, K4=0, K5=0
EIGRP maximum hopcount 100
EIGRP maximum metric variance 1
Redistributing: eigrp 10
Automatic network summarization is not in effect
Maximum path: 4
Routing for Networks:
10.0.0.0
192.168.10.0
192.168.20.0
Routing Information Sources:
Gateway Distance Last Update
10.1.3.1 90 6465
10.1.2.1 90 6794
Distance: internal 90 external 170
Routing Protocol is "rip"
Sending updates every 30 seconds, next due in 21 seconds
Invalid after 180 seconds, hold down 180, flushed after 240
Outgoing update filter list for all interfaces is not set
Incoming update filter list for all interfaces is not set
Redistributing: rip
Default version control: send version 2, receive 2
Interface Send Recv Triggered RIP Key-chain
FastEthernet0/0 2 2
FastEthernet0/1 2 2
Serial0/0/0 2 2
Serial0/0/1 2 2
Automatic network summarization is not in effect
Maximum path: 4
Routing for Networks:
10.0.0.0
192.168.10.0
192.168.20.0
Passive Interface(s):
Routing Information Sources:
Gateway Distance Last Update
10.1.3.1 120 00:00:06
10.1.2.1 120 00:00:06
Distance: (default is 120)
IOS 12.4
R2#
show ip protocols
Routing Protocol is "eigrp 10 "
Outgoing update filter list for all interfaces is not set
Incoming update filter list for all interfaces is not set
Default networks flagged in outgoing updates
Default networks accepted from incoming updates
EIGRP metric weight K1=1, K2=0, K3=1, K4=0, K5=0
EIGRP maximum hopcount 100
EIGRP maximum metric variance 1
Redistributing: eigrp 10
Automatic network summarization is not in effect
Maximum path: 4
Routing for Networks:
10.0.0.0
192.168.30.0
192.168.40.0
Routing Information Sources:
Gateway Distance Last Update
10.1.4.1 90 7955
Distance: internal 90 external 170
Routing Protocol is "rip"
Sending updates every 30 seconds, next due in 11 seconds
Invalid after 180 seconds, hold down 180, flushed after 240
Outgoing update filter list for all interfaces is not set
Incoming update filter list for all interfaces is not set
Redistributing: rip
Default version control: send version 2, receive 2
Interface Send Recv Triggered RIP Key-chain
FastEthernet0/0 2 2
FastEthernet0/1 2 2
Serial0/0/0 2 2
Automatic network summarization is in effect
Maximum path: 4
Routing for Networks:
10.0.0.0
192.168.30.0
192.168.40.0
Passive Interface(s):
Routing Information Sources:
Gateway Distance Last Update
10.1.4.1 120 00:00:20
Distance: (default is 120)
IOS 15.1
R3#
show ip protocols
Routing Protocol is "eigrp 10 "
Outgoing update filter list for all interfaces is not set
Incoming update filter list for all interfaces is not set
Default networks flagged in outgoing updates
Default networks accepted from incoming updates
Redistributing: eigrp 10
EIGRP-IPv4 Protocol for AS(10)
Metric weight K1=1, K2=0, K3=1, K4=0, K5=0
NSF-aware route hold timer is 240
Router-ID: 10.1.5.2
Topology : 0 (base)
Active Timer: 3 min
Distance: internal 90 external 170
Maximum path: 4
Maximum hopcount 100
Maximum metric variance 1
Automatic Summarization: disabled
Automatic address summarization:
Maximum path: 4
Routing for Networks:
10.0.0.0
172.16.0.0
Routing Information Sources:
Gateway Distance Last Update
10.1.5.1 90 0
Distance: internal 90 external 170
Routing Protocol is "rip"
Sending updates every 30 seconds, next due in 27 seconds
Invalid after 180 seconds, hold down 180, flushed after 240
Outgoing update filter list for all interfaces is not set
Incoming update filter list for all interfaces is not set
Redistributing: rip
Default version control: send version 2, receive 2
Interface Send Recv Triggered RIP Key-chain
Dot11Radio0/0/0 2 2
FastEthernet0/0 2 2
Automatic network summarization is not in effect
Maximum path: 4
Routing for Networks:
10.0.0.0
172.16.0.0
Passive Interface(s):
Routing Information Sources:
Gateway Distance Last Update
10.1.5.1 120 00:00:02
Distance: (default is 120)
I'm also noticing that we have inconsistent auto-summarization settings- I was having trouble with this earlier. The book discusses
getting rid of the 172.16.0.0 summarized route in the EIGRP settings. I was not able to get rid of it, I think because RIP is still on, and RIP forces auto-summary
Part of the challenge here is that the book is strictly dealing with IOS 12.4
I will now make sure to turn auto summary off for both RIP and EIGRP on each of the four routers.
OK the part I am forgetting is that we are running RIP V2 which does not force auto-summary but runs it optionally, and we must turn it off to avoid auto summarization.
Corp(config)#
router rip
Corp(config-router)#
no auto-summary
Corp(config-router)#
router eigrp 10
Corp(config-router)#
no auto-summary
R1(config)#
router rip
R1(config-router)#
no auto-summary
R1(config-router)#
router eigrp 10
R1(config-router)#
no auto-summary
R1(config)#
router rip
R1(config-router)#
no auto-summary
R1(config-router)#
router eigrp 10
R2(config-router)#
no auto-summary
R3(config)#
router rip
R3(config-router)#
no auto-summary
R3(config-router)#
router eigrp 10
R3(config-router)#
no auto-summary
and lets see how the output looks now. This time I'll do show ip protocols and
show ip route side by side for each router
IOS 15.1
Corp#
show ip protocols
Routing Protocol is "eigrp 10 "
Outgoing update filter list for all interfaces is not set
Incoming update filter list for all interfaces is not set
Default networks flagged in outgoing updates
Default networks accepted from incoming updates
Redistributing: eigrp 10
EIGRP-IPv4 Protocol for AS(10)
Metric weight K1=1, K2=0, K3=1, K4=0, K5=0
NSF-aware route hold timer is 240
Router-ID: 10.1.1.1
Topology : 0 (base)
Active Timer: 3 min
Distance: internal 90 external 170
Maximum path: 4
Maximum hopcount 100
Maximum metric variance 1
Automatic Summarization: disabled
Automatic address summarization:
Maximum path: 4
Routing for Networks:
10.0.0.0
Routing Information Sources:
Gateway Distance Last Update
10.1.5.2 90 0
10.1.3.2 90 6464
10.1.2.2 90 6795
10.1.4.2 90 7955
Distance: internal 90 external 170
Routing Protocol is "rip" doesnt necessarily mean RIPv1
Sending updates every 30 seconds, next due in 3 seconds
Invalid after 180 seconds, hold down 180, flushed after 240
Outgoing update filter list for all interfaces is not set
Incoming update filter list for all interfaces is not set
Redistributing: rip
Default version control: send version 2, receive 2 RIPv2 is specified
Interface Send Recv Triggered RIP Key-chain
Vlan1 2 2
FastEthernet0/0 2 2
Serial0/1/0 2 2
Serial0/0/1 2 2
Serial0/0/0 2 2
Automatic network summarization is not in effect
Maximum path: 4
Routing for Networks:
10.0.0.0
Passive Interface(s):
Routing Information Sources:
Gateway Distance Last Update
10.1.5.2 120 00:00:02
10.1.3.2 120 00:00:21
10.1.2.2 120 00:00:21
10.1.4.2 120 00:00:04
Distance: (default is 120)
IOS 15.1
Corp#
show ip route
Gateway of last resort is not set
10.0.0.0/8 is variably subnetted, 10 subnets, 2 masks
C 10.1.1.0/24 is directly connected, Vlan1
L 10.1.1.1/32 is directly connected, Vlan1
C 10.1.2.0/24 is directly connected, Serial0/0/0
L 10.1.2.1/32 is directly connected, Serial0/0/0
C 10.1.3.0/24 is directly connected, Serial0/0/1
L 10.1.3.1/32 is directly connected, Serial0/0/1
C 10.1.4.0/24 is directly connected, Serial0/1/0
L 10.1.4.1/32 is directly connected, Serial0/1/0
C 10.1.5.0/24 is directly connected, FastEthernet0/0
L 10.1.5.1/32 is directly connected, FastEthernet0/0
172.16.0.0/24 is subnetted, 1 subnets
D 172.16.10.0/24 [90/28160] via 10.1.5.2, 00:57:25, FastEthernet0/0
D 192.168.10.0/24 [90/2172416] via 10.1.3.2, 00:57:20, Serial0/0/1
[90/2172416] via 10.1.2.2, 00:57:20, Serial0/0/0
D 192.168.20.0/24 [90/2172416] via 10.1.3.2, 00:57:20, Serial0/0/1
[90/2172416] via 10.1.2.2, 00:57:20, Serial0/0/0
D 192.168.30.0/24 [90/2172416] via 10.1.4.2, 00:57:19, Serial0/1/0
D 192.168.40.0/24 [90/2172416] via 10.1.4.2, 00:57:19, Serial0/1/0
IOS 12.4
R1#
show ip protocols
Routing Protocol is "eigrp 10 "
Outgoing update filter list for all interfaces is not set
Incoming update filter list for all interfaces is not set
Default networks flagged in outgoing updates
Default networks accepted from incoming updates
EIGRP metric weight K1=1, K2=0, K3=1, K4=0, K5=0
EIGRP maximum hopcount 100
EIGRP maximum metric variance 1
Redistributing: eigrp 10
Automatic network summarization is not in effect
Maximum path: 4
Routing for Networks:
10.0.0.0
192.168.10.0
192.168.20.0
Routing Information Sources:
Gateway Distance Last Update
10.1.3.1 90 6465
10.1.2.1 90 6794
Distance: internal 90 external 170
Routing Protocol is "rip"
Sending updates every 30 seconds, next due in 26 seconds
Invalid after 180 seconds, hold down 180, flushed after 240
Outgoing update filter list for all interfaces is not set
Incoming update filter list for all interfaces is not set
Redistributing: rip
Default version control: send version 2, receive 2
Interface Send Recv Triggered RIP Key-chain
FastEthernet0/0 2 2
FastEthernet0/1 2 2
Serial0/0/0 2 2
Serial0/0/1 2 2
Automatic network summarization is not in effect
Maximum path: 4
Routing for Networks:
10.0.0.0
192.168.10.0
192.168.20.0
Passive Interface(s):
Routing Information Sources:
Gateway Distance Last Update
10.1.3.1 120 00:00:03
10.1.2.1 120 00:00:03
Distance: (default is 120)
IOS 12.4
R1#
show ip route
Gateway of last resort is not set
10.0.0.0/24 is subnetted, 5 subnets
D 10.1.1.0 [90/27769856] via 10.1.3.1, 00:54:47, Serial0/0/1
[90/27769856] via 10.1.2.1, 00:54:47, Serial0/0/0
C 10.1.2.0 is directly connected, Serial0/0/0
C 10.1.3.0 is directly connected, Serial0/0/1
D 10.1.4.0 [90/2681856] via 10.1.3.1, 00:54:47, Serial0/0/1
[90/2681856] via 10.1.2.1, 00:54:47, Serial0/0/0
D 10.1.5.0 [90/2172416] via 10.1.3.1, 00:54:47, Serial0/0/1
[90/2172416] via 10.1.2.1, 00:54:47, Serial0/0/0
172.16.0.0/24 is subnetted, 1 subnets
D 172.16.10.0 [90/2172416] via 10.1.3.1, 00:54:47, Serial0/0/1
[90/2172416] via 10.1.2.1, 00:54:47, Serial0/0/0
C 192.168.10.0/24 is directly connected, FastEthernet0/0
C 192.168.20.0/24 is directly connected, FastEthernet0/1
D 192.168.30.0/24 [90/2684416] via 10.1.3.1, 00:54:46, Serial0/0/1
[90/2684416] via 10.1.2.1, 00:54:46, Serial0/0/0
D 192.168.40.0/24 [90/2684416] via 10.1.3.1, 00:54:46, Serial0/0/1
[90/2684416] via 10.1.2.1, 00:54:46, Serial0/0/0
note that the DUAL routes being advertised from the 10.0.0.0 networks are all specific to the third octet.. that's because we are reading those routes
from their source, aka the router which they are directly connected to, Corp.
and on Corp, those networks were added to the interfaces with a /24 mask.
so even though our EIGRP config doesnt specifically include /24 networks.. we told it to include anything with a 10.x.x.x
Corp is advertising to R1 our /24 network interfaces that have a 10 in the first octet, EXCEPT the two which are directly connected to R1
10.1.1.0
10.1.4.0
10.1.5.0
are assumed to be the subnets based on the info we configured, which was 10.1.4.1/24 on corp, and 10.1.4.2/24 on r2 s0/0/0
nowhere in this configuration, have we entered the 10.1.4.0 network.
EIGRP is figuring it out based on the /24 mask we gave when assiging he IPs to the interfaces
IOS 12.4
R2#
show ip protocols
Routing Protocol is "eigrp 10 "
Outgoing update filter list for all interfaces is not set
Incoming update filter list for all interfaces is not set
Default networks flagged in outgoing updates
Default networks accepted from incoming updates
EIGRP metric weight K1=1, K2=0, K3=1, K4=0, K5=0
EIGRP maximum hopcount 100
EIGRP maximum metric variance 1
Redistributing: eigrp 10
Automatic network summarization is not in effect
Maximum path: 4
Routing for Networks:
10.0.0.0
192.168.30.0
192.168.40.0
Routing Information Sources:
Gateway Distance Last Update
10.1.4.1 90 7955
Distance: internal 90 external 170
Routing Protocol is "rip"
Sending updates every 30 seconds, next due in 18 seconds
Invalid after 180 seconds, hold down 180, flushed after 240
Outgoing update filter list for all interfaces is not set
Incoming update filter list for all interfaces is not set
Redistributing: rip
Default version control: send version 2, receive 2
Interface Send Recv Triggered RIP Key-chain
FastEthernet0/0 2 2
FastEthernet0/1 2 2
Serial0/0/0 2 2
Automatic network summarization is not in effect
Maximum path: 4
Routing for Networks:
10.0.0.0
192.168.30.0
192.168.40.0
Passive Interface(s):
Routing Information Sources:
Gateway Distance Last Update
10.1.4.1 120 00:00:07
Distance: (default is 120)
IOS 12.4
R2#
show ip route
Gateway of last resort is not set
10.0.0.0/24 is subnetted, 5 subnets
D 10.1.1.0 [90/27769856] via 10.1.4.1, 00:59:10, Serial0/0/0
D 10.1.2.0 [90/2681856] via 10.1.4.1, 00:59:10, Serial0/0/0
D 10.1.3.0 [90/2681856] via 10.1.4.1, 00:59:10, Serial0/0/0
C 10.1.4.0 is directly connected, Serial0/0/0
D 10.1.5.0 [90/2172416] via 10.1.4.1, 00:59:10, Serial0/0/0
172.16.0.0/24 is subnetted, 1 subnets
D 172.16.10.0 [90/2172416] via 10.1.4.1, 00:59:10, Serial0/0/0
D 192.168.10.0/24 [90/2684416] via 10.1.4.1, 00:59:10, Serial0/0/0
D 192.168.20.0/24 [90/2684416] via 10.1.4.1, 00:59:10, Serial0/0/0
C 192.168.30.0/24 is directly connected, FastEthernet0/0
C 192.168.40.0/24 is directly connected, FastEthernet0/1
IOS 15.1
R3#
show ip protocols
Routing Protocol is "eigrp 10 "
Outgoing update filter list for all interfaces is not set
Incoming update filter list for all interfaces is not set
Default networks flagged in outgoing updates
Default networks accepted from incoming updates
Redistributing: eigrp 10
EIGRP-IPv4 Protocol for AS(10)
Metric weight K1=1, K2=0, K3=1, K4=0, K5=0
NSF-aware route hold timer is 240
Router-ID: 10.1.5.2
Topology : 0 (base)
Active Timer: 3 min
Distance: internal 90 external 170
Maximum path: 4
Maximum hopcount 100
Maximum metric variance 1
Automatic Summarization: disabled
Automatic address summarization:
Maximum path: 4
Routing for Networks:
10.0.0.0
172.16.0.0
Routing Information Sources:
Gateway Distance Last Update
10.1.5.1 90 0
Distance: internal 90 external 170
Routing Protocol is "rip"
Sending updates every 30 seconds, next due in 15 seconds
Invalid after 180 seconds, hold down 180, flushed after 240
Outgoing update filter list for all interfaces is not set
Incoming update filter list for all interfaces is not set
Redistributing: rip
Default version control: send version 2, receive 2
Interface Send Recv Triggered RIP Key-chain
Dot11Radio0/0/0 2 2
FastEthernet0/0 2 2
Automatic network summarization is not in effect
Maximum path: 4
Routing for Networks:
10.0.0.0
172.16.0.0
Passive Interface(s):
Routing Information Sources:
Gateway Distance Last Update
10.1.5.1 120 00:00:14
Distance: (default is 120)
IOS 15.1
R3#
show ip route
Gateway of last resort is 10.1.5.1 to network 0.0.0.0
10.0.0.0/8 is variably subnetted, 6 subnets, 2 masks
D 10.1.1.0/24 [90/25628160] via 10.1.5.1, 00:59:52, FastEthernet0/0
D 10.1.2.0/24 [90/2172416] via 10.1.5.1, 00:59:47, FastEthernet0/0
D 10.1.3.0/24 [90/2172416] via 10.1.5.1, 00:59:52, FastEthernet0/0
D 10.1.4.0/24 [90/2172416] via 10.1.5.1, 00:59:52, FastEthernet0/0
C 10.1.5.0/24 is directly connected, FastEthernet0/0
L 10.1.5.2/32 is directly connected, FastEthernet0/0
172.16.0.0/16 is variably subnetted, 2 subnets, 2 masks
C 172.16.10.0/24 is directly connected, Dot11Radio0/0/0
L 172.16.10.1/32 is directly connected, Dot11Radio0/0/0
D 192.168.10.0/24 [90/2174976] via 10.1.5.1, 00:59:47, FastEthernet0/0
D 192.168.20.0/24 [90/2174976] via 10.1.5.1, 00:59:47, FastEthernet0/0
D 192.168.30.0/24 [90/2174976] via 10.1.5.1, 00:59:46, FastEthernet0/0
D 192.168.40.0/24 [90/2174976] via 10.1.5.1, 00:59:46, FastEthernet0/0
S* 0.0.0.0/0 [1/0] via 10.1.5.1
Observations:
Since this is a 15.1 router, we always get a "L" local route when
we have a "C" connected route. In R3's case, the 172.16.10.0 network
is directly connected. The interface which connects it, 172.16.10.1,
counts as a "local" route. This is NOT the case on the 12.4 routers.
looking to the left, our protocol output tells us two key facts for both EIGRP and RIP:
Routing for networks:
10.0.0.0
172.16.0.0
R3 is responsible for *sending* data about these two networks to our other EIGRP routers...
"I'm R3 and I can connect you to networks on the R3
router or networks on the Corp router"
Notice how the 192 networks arent listed. R3 isnt connected to a 192 network directly, nor is it connected to a neighbor who is directly connected.
If I, as a client, am sending data to a 192 network from the 172 network, I will start
at R3. Since R3 is receiving routes for the 192 networks via Corp, I will be able to reach a 192 network via Corp.
My connection to corp will happen VIA a "10.0.0.0" route.
R3 is technically only routing for 172 and 10 networks. Beyond that, it could potentially connect to many other different networks. But in terms of the R3 routing table,
all it can offer is a path out to the 172 network or the 10 network
Routing information sources:
10.1.5.1
In this case I can see that R3 is receiving routing data from one interface only,
and that is it's link to Corp. Some of the data we are receiving from Corp actually originates
at other routers, but we cant see that here; the data comes to us from Corp, and that is all we know
EIGRP TERMINOLOGY
FEASIBLE DISTANCE (FD)
the best metric among all paths, including to the next hop neighbor. You will only see the route with the lowest FD appear in the routing table
The FD is calculated by adding the reported distance from the neighbor (AD) plus the metric to that neighbor
ADVERTISED DISTANCE (AD)
the metric of a remote network as reported by a neighbor, listed second in parenthesis in toplogy table
P 192.168.20.0/24, 2 successors, FD is 2172416
via 10.1.3.2 (2172416/28160), Serial0/0/1
feasible / advertised
Neighbor Table
each router keeps state information about adjacent neighbors.. When a new neighbor is learned, the address and interface are recorded.
The neighbor table is stored in RAM.
Sequence numbres are used to match acks with update packets. The last squence number received from a neighbor is recorded so out of order packets
can be detected
Topology Table
acted upon by DUAL Diffusing Update Alogorithm. Contains all destinations advertised by neighboring routers.
For each neighbor, the adversited distance, which comes only from that neighbor's routing table, is recorded
The feasible distance is also recorded.
Feasible Successor
a PATH whose advertised distance is less than the feasible distance of the current succesor, and is considered a backup route.
EIGRP keeps up to 16 feasible successors in the toplogy table.
The one with the best metric (The Successor) is copied and placed into the routing table
Successor
the best route to a remote network, used by EIGRP to forward traffic. It's backed up by a feasible successor, if one is available.
lets demo some more of the commands
VERIFYING EIGRP
several commands available to verify and troubleshoot
show ip route
show the entire routing table
show ip route eigrp
show only EIGRP entries in the routing table
show ip eigrp neighbors
show all EIGRP neigbors
show ip eigrp topology
show entries in the EIGRP topology table
show ip protocols
shows routing protocols configuration
debug eigrp packet
shows hello packets sent/received between adjacent routers
debug ip eigrp events
shows EIGRP changes and updates as they occur on your network
Corp#
show ip eigrp ?
interfaces IP-EIGRP interfaces
neighbors IP-EIGRP neighbors
topology IP-EIGRP Topology Table
traffic IP-EIGRP Traffic Statistics
Corp#
show ip eigrp topology
IP-EIGRP Topology Table for AS 10/ID(10.1.5.1)
Codes: P - Passive, A - Active, U - Update, Q - Query, R - Reply,
r - Reply status
P 10.1.1.0/24, 1 successors, FD is 25625600
via Connected, Vlan1
P 10.1.2.0/24, 1 successors, FD is 2169856
via Connected, Serial0/0/0
P 10.1.3.0/24, 1 successors, FD is 2169856
via Connected, Serial0/0/1
P 10.1.4.0/24, 1 successors, FD is 2169856
via Connected, Serial0/1/0
P 10.1.5.0/24, 1 successors, FD is 28160
via Connected, FastEthernet0/0
P 172.16.10.0/24, 1 successors, FD is 28160
via 10.1.5.2 (28160/25600), FastEthernet0/0
P 192.168.10.0/24, 2 successors, FD is 2172416
via 10.1.3.2 (2172416/28160), Serial0/0/1
via 10.1.2.2 (2172416/28160), Serial0/0/0
P 192.168.20.0/24, 2 successors, FD is 2172416
via 10.1.3.2 (2172416/28160), Serial0/0/1
via 10.1.2.2 (2172416/28160), Serial0/0/0
P 192.168.30.0/24, 1 successors, FD is 2172416
via 10.1.4.2 (2172416/28160), Serial0/1/0
P 192.168.40.0/24, 1 successors, FD is 2172416
via 10.1.4.2 (2172416/28160), Serial0/1/0
the "P" preceding each entry is for PASSIVE
these routes are in a passive state, which is good
if they move to an ACTIVE state, it means the have lost their path in the network and looking for a replacement.
Each entry also shows the FEASIBLE DISTANCE, the next hop address, and the local egress interface
Corp#
show ip eigrp neighbors
IP-EIGRP neighbors for process 10
H Address Interface Hold Uptime SRTT RTO Q Seq
(sec) (ms) Cnt Num
0 10.1.5.2 Fa0/0 14 02:00:05 40 1000 0 19
1 10.1.3.2 Se0/0/1 13 01:59:59 40 1000 0 14
2 10.1.2.2 Se0/0/0 13 01:59:59 40 1000 0 13
3 10.1.4.2 Se0/1/0 12 01:59:57 40 1000 0 15
fields:
H - the order in which the neighbors were discovered
hold - how long the router will wait for a hello packet
uptime - how long the neigborship has been established
SRTT - smooth round trip timer - the time it takes for a round trip from this router, to neighbor, and back.
SRTT is used to determine how long to wait for a MULTICAST reply.
if a reply isnt received in time, the router switches to UNICASTS
RTO - Retransmission Time Out- is the time EIGRP waits before retransmitting a packet from the retransmission queue
Q - indicates wheter there are oustanding messages in the queue
Seq - indicates the sequence number of the last update from that neighbor. This is used to maintain syncrhonization and avoid duplicate
or out-of-sequence processing of messages
Corp#
show ip route eigrp
172.16.0.0/24 is subnetted, 1 subnets
D 172.16.10.0 [90/28160] via 10.1.5.2, 02:08:04, FastEthernet0/0
D 192.168.10.0/24 [90/2172416] via 10.1.3.2, 02:07:59, Serial0/0/1
[90/2172416] via 10.1.2.2, 02:07:59, Serial0/0/0
D 192.168.20.0/24 [90/2172416] via 10.1.3.2, 02:07:59, Serial0/0/1
[90/2172416] via 10.1.2.2, 02:07:59, Serial0/0/0
D 192.168.30.0/24 [90/2172416] via 10.1.4.2, 02:07:58, Serial0/1/0
D 192.168.40.0/24 [90/2172416] via 10.1.4.2, 02:07:58, Serial0/1/0
Corp#
show ip eigrp interfaces
IP-EIGRP interfaces for process 10
Xmit Queue Mean Pacing Time Multicast Pending
Interface Peers Un/Reliable SRTT Un/Reliable Flow Timer Routes
Vlan 0 0/0 1236 0/10 0 0
Fa0/0 1 0/0 1236 0/10 0 0
Se0/1/0 1 0/0 1236 0/10 0 0
Se0/0/1 1 0/0 1236 0/10 0 0
Se0/0/0 1 0/0 1236 0/10 0 0
Corp#
show ip protocols
Routing Protocol is "eigrp 10 "
Outgoing update filter list for all interfaces is not set
Incoming update filter list for all interfaces is not set
Default networks flagged in outgoing updates
Default networks accepted from incoming updates
Redistributing: eigrp 10
EIGRP-IPv4 Protocol for AS(10)
Metric weight K1=1, K2=0, K3=1, K4=0, K5=0 using K1 bandwidth and K2 delay by default
NSF-aware route hold timer is 240
Router-ID: 10.1.1.1
Topology : 0 (base)
Active Timer: 3 min
Distance: internal 90 external 170
Maximum path: 4
Maximum hopcount 100
Maximum metric variance 1
Automatic Summarization: disabled
Automatic address summarization:
Maximum path: 4
Routing for Networks:
10.0.0.0
Routing Information Sources:
Gateway Distance Last Update
10.1.5.2 90 0
10.1.3.2 90 8936
10.1.4.2 90 9511
10.1.2.2 90 9597
Distance: internal 90 external 170
Routing Protocol is "rip"
Sending updates every 30 seconds, next due in 13 seconds
Invalid after 180 seconds, hold down 180, flushed after 240
Outgoing update filter list for all interfaces is not set
Incoming update filter list for all interfaces is not set
Redistributing: rip
Default version control: send version 2, receive 2
Interface Send Recv Triggered RIP Key-chain
Vlan1 2 2
FastEthernet0/0 2 2
Serial0/0/1 2 2
Serial0/1/0 2 2
Serial0/0/0 2 2
Automatic network summarization is not in effect
Maximum path: 4
Routing for Networks:
10.0.0.0
Passive Interface(s):
Routing Information Sources:
Gateway Distance Last Update
10.1.5.2 120 00:00:05
10.1.3.2 120 00:00:12
10.1.2.2 120 00:00:12
10.1.4.2 120 00:00:17
Distance: (default is 120)
corp#
debug eigrp packet
break into two columns for readability
Observations:
There doesnt appear to be a pattern in the order each router is addressed, except that the TO's and FROM"s are grouped together
The TO messages dont show the destination IP, only the egress local interface
The FROM messages do show the remote IP, as well as the local ingress interface
Corp#
EIGRP: Received HELLO on FastEthernet0/0 nbr 10.1.5.2
AS 10, Flags 0x0, Seq 18/0 idbQ 0/0
hello from R3
Corp#
EIGRP: Received HELLO on Serial0/1/0 nbr 10.1.4.2
AS 10, Flags 0x0, Seq 16/0 idbQ 0/0
hello from R2
Corp#
EIGRP: Received HELLO on Serial0/0/0 nbr 10.1.2.2
AS 10, Flags 0x0, Seq 19/0 idbQ 0/0
hello from R1
------------------------------------------------------------
Corp#
EIGRP: Sending HELLO on Serial0/1/0
AS 10, Flags 0x0, Seq 21/0 idbQ 0/0 iidbQ un/rely 0/0
hello to R2
Corp#
EIGRP: Sending HELLO on FastEthernet0/0
AS 10, Flags 0x0, Seq 21/0 idbQ 0/0 iidbQ un/rely 0/0
hello to R3
Corp#
EIGRP: Sending HELLO on Serial0/0/1
AS 10, Flags 0x0, Seq 21/0 idbQ 0/0 iidbQ un/rely 0/0
hello to R1
Corp#
EIGRP: Sending HELLO on Serial0/0/0
AS 10, Flags 0x0, Seq 21/0 idbQ 0/0 iidbQ un/rely 0/0
hello to R1
Corp#
EIGRP: Sending HELLO on Vlan1
AS 10, Flags 0x0, Seq 21/0 idbQ 0/0 iidbQ un/rely 0/0
hello to switch card (not a router....)
------------------------------------------------------------
Corp#
EIGRP: Received HELLO on Serial0/0/1 nbr 10.1.3.2
AS 10, Flags 0x0, Seq 19/0 idbQ 0/0
hello from R1
Corp#
EIGRP: Received HELLO on FastEthernet0/0 nbr 10.1.5.2
AS 10, Flags 0x0, Seq 18/0 idbQ 0/0
hello from R3
Corp#
EIGRP: Received HELLO on Serial0/0/0 nbr 10.1.2.2
AS 10, Flags 0x0, Seq 19/0 idbQ 0/0
hello from R1
Corp#
EIGRP: Received HELLO on Serial0/1/0 nbr 10.1.4.2
AS 10, Flags 0x0, Seq 16/0 idbQ 0/0
hello from R2
------------------------------------------------------------
Corp#
EIGRP: Sending HELLO on Serial0/1/0
AS 10, Flags 0x0, Seq 21/0 idbQ 0/0 iidbQ un/rely 0/0
hello to R2... no neighbor IP?
Corp#
EIGRP: Sending HELLO on Serial0/0/0
AS 10, Flags 0x0, Seq 21/0 idbQ 0/0 iidbQ un/rely 0/0
hello to R1... no neighbor IP?
Corp#
EIGRP: Sending HELLO on FastEthernet0/0
AS 10, Flags 0x0, Seq 21/0 idbQ 0/0 iidbQ un/rely 0/0
hello to R3... no neighbor IP?
Corp#
EIGRP: Sending HELLO on Serial0/0/1
AS 10, Flags 0x0, Seq 21/0 idbQ 0/0 iidbQ un/rely 0/0
hello to R1
Corp#
EIGRP: Sending HELLO on Vlan1
AS 10, Flags 0x0, Seq 21/0 idbQ 0/0 iidbQ un/rely 0/0
hello to switch card (not a router)
------------------------------------------------------------
OUTPUT CONTINUES IN NEXT COLUMN
Corp#
EIGRP: Received HELLO on Serial0/0/1 nbr 10.1.3.2
AS 10, Flags 0x0, Seq 19/0 idbQ 0/0
hello from R1
Corp#
EIGRP: Received HELLO on FastEthernet0/0 nbr 10.1.5.2
AS 10, Flags 0x0, Seq 18/0 idbQ 0/0
hello from R3
Corp#
EIGRP: Received HELLO on Serial0/0/0 nbr 10.1.2.2
AS 10, Flags 0x0, Seq 19/0 idbQ 0/0
hello from R1
Corp#
EIGRP: Received HELLO on Serial0/1/0 nbr 10.1.4.2
AS 10, Flags 0x0, Seq 16/0 idbQ 0/0
hello from R2
------------------------------------------------------------
Corp#
EIGRP: Sending HELLO on Serial0/1/0
AS 10, Flags 0x0, Seq 21/0 idbQ 0/0 iidbQ un/rely 0/0
hello to R2
Corp#
EIGRP: Sending HELLO on Serial0/0/0
AS 10, Flags 0x0, Seq 21/0 idbQ 0/0 iidbQ un/rely 0/0
hello to R1
Corp#
EIGRP: Sending HELLO on Vlan1
AS 10, Flags 0x0, Seq 21/0 idbQ 0/0 iidbQ un/rely 0/0
hello to Corp switchcard
Corp#
EIGRP: Sending HELLO on Serial0/0/1
AS 10, Flags 0x0, Seq 21/0 idbQ 0/0 iidbQ un/rely 0/0
hello to R1
Corp#
EIGRP: Sending HELLO on FastEthernet0/0
AS 10, Flags 0x0, Seq 21/0 idbQ 0/0 iidbQ un/rely 0/0
hello to R3... no neighbor IP?
------------------------------------------------------------
Corp#
EIGRP: Received HELLO on Serial0/0/1 nbr 10.1.3.2
AS 10, Flags 0x0, Seq 19/0 idbQ 0/0
hello from R1
Corp#
EIGRP: Received HELLO on FastEthernet0/0 nbr 10.1.5.2
AS 10, Flags 0x0, Seq 18/0 idbQ 0/0
hello from R3
Corp#
EIGRP: Received HELLO on Serial0/1/0 nbr 10.1.4.2
AS 10, Flags 0x0, Seq 16/0 idbQ 0/0
hello from R2
Corp#
EIGRP: Received HELLO on Serial0/0/0 nbr 10.1.2.2
AS 10, Flags 0x0, Seq 19/0 idbQ 0/0
hello from R1
------------------------------------------------------------
Corp#
EIGRP: Sending HELLO on Serial0/1/0
AS 10, Flags 0x0, Seq 21/0 idbQ 0/0 iidbQ un/rely 0/0
hello to R2
Corp#
EIGRP: Sending HELLO on Vlan1
AS 10, Flags 0x0, Seq 21/0 idbQ 0/0 iidbQ un/rely 0/0
hello to Corp switchcard
EIGRP: Sending HELLO on Serial0/0/0
AS 10, Flags 0x0, Seq 21/0 idbQ 0/0 iidbQ un/rely 0/0
hello to R1
EIGRP: Sending HELLO on Serial0/0/1
AS 10, Flags 0x0, Seq 21/0 idbQ 0/0 iidbQ un/rely 0/0
hello to R1
Corp#
EIGRP: Sending HELLO on FastEthernet0/0
AS 10, Flags 0x0, Seq 21/0 idbQ 0/0 iidbQ un/rely 0/0
hello to R3
------------------------------------------------------------
Now some videos. To reinforce EIGRP concepts, and lead into OSPF
OSPF - OPEN SHORTEST PATH FIRST
Before enabling OSPF, we'll turn off RIP and EIGRP on all four routers.
Device(config)#
no router eigrp 10
Device(config)#
no router rip
The OSPF configs for the local egress ip address
Corp(config)#
router ospf 132
Corp(config)#
network 10.1.0.0 0.0.255.255 area 0
R1(config)#
router ospf 1
R1(config)#
network 10.1.0.0 0.0.255.255 area 0
R1(config)#
network 192.168.0.0 0.0.255.255 area 0
R2(config)#
router ospf 45678
R2(config)#
network 10.0.0.0 0.0.0.255 area 0
R2(config)#
network 192.168.30.1 0.0.0.0 area 0
R2(config)#
network 192.168.40.1 0.0.0.0 area 0
all 32 bits of the mask are specified for the 192 entries;
these are not network id's, they are HOST id's of the specific interfaces, which are EGRESS interfaces on the router we are configuring
R3(config)#
router ospf 1
R2(config)#
network 10.1.5.2 0.0.0.255 area 0
R2(config)#
network 172.16.10.0 0.0.0.255 area 0
Wildcard Masks
these notes are not intended to be a precise explanation of wlidcard masking, but rather a look into my thought process as I am learning the concept.
resources:
traceroute blog examples
routerjockey blog examples
subnetonline wildcard calculator
Ch 9 Exam Essentials
1. Know EIGRP features
classless (like RipV2 and OSPF)
distance vector
supports IP, IPX, appleTalk, IPV6
supports summaries and discontiguous networks
uses the Diffusing Update Algorithm (DUAL) to maintain route information
uses RTP to communicate with other EIGRP routers
uses the concept of an autonomous system to describe the set of contiguous routers that run the same routing protocol and share routing information
considered CLASSLESS- includes the subnet mask in its route updates
sends traditional distance-vector updates containing info about networks plus the cost of reaching them from the perspective of the advertising router
but not strictly distance-vector. Has link-state characteristics: synchronizes routing tables between neighbors at startup and then sends specific updates only when topology changes.
max hop count of 255 (default is 100)
but hop count is NOT a metric, like in RIP. Hop count is how many routers an EIGRP route update can traverse before being discarded. This limits the size of the AS.
2. Know how to configure EIGRP
the router eigrp [as] command turns EIGRP routing on in the router. Unlike RIPv1, EIGRP uses classless routing. BUT you can still configure as classful.
R1(config)#
router eigrp 10
enters router config mode
R1(config-router)#
network 10.0.0.0
on this router, interfaces that fall within 10.0.0.0 will advertise EIGRP info
3. Know how to verify EIGRP operation
Corp#
show ip
protocols
Corp#
show ip
route
Corp#
show ip
route eigrp
Corp#
show ip
eigrp neighbors
Corp#
show ip
eigrp topology
Corp#
show ip
eigrp interfaces
Corp#
show ip
protocols
info about all active routing protocols
Routing Protocol is "eigrp 10 "
Outgoing update filter list for all interfaces is not set
Incoming update filter list for all interfaces is not set
Default networks flagged in outgoing updates
Default networks accepted from incoming updates
Redistributing: eigrp 10
EIGRP-IPv4 Protocol for AS(10)
Metric weight K1=1, K2=0, K3=1, K4=0, K5=0
NSF-aware route hold timer is 240
Router-ID: 10.1.1.1
Topology : 0 (base)
Active Timer: 3 min
Distance: internal 90 external 170
Maximum path: 4
Maximum hopcount 100
Maximum metric variance 1
Automatic Summarization: disabled
Automatic address summarization:
Maximum path: 4
Routing for Networks:
10.0.0.0
Routing Information Sources:
Gateway Distance Last Update
10.1.2.2 90 200105
10.1.3.2 90 200113
10.1.4.2 90 254351
10.1.5.2 90 303742
Distance: internal 90 external 170
Corp#
show ip
protocols
(continued)
Routing Protocol is "rip"
Sending updates every 30 seconds, next due in 6 seconds
Invalid after 180 seconds, hold down 180, flushed after 240
Outgoing update filter list for all interfaces is not set
Incoming update filter list for all interfaces is not set
Redistributing: rip
Default version control: send version 2, receive 2
Interface Send Recv Triggered RIP Key-chain
Vlan1 2 2
FastEthernet0/0 2 2
Serial0/1/0 2 2
Serial0/0/1 2 2
Serial0/0/0 2 2
Automatic network summarization is not in effect
Maximum path: 4
Routing for Networks:
10.0.0.0
Passive Interface(s):
Routing Information Sources:
Gateway Distance Last Update
10.1.5.2 120 00:00:15
10.1.3.2 120 00:00:01
10.1.2.2 120 00:00:01
10.1.4.2 120 00:00:17
Distance: (default is 120)
Corp#
show ip
route
entire routing table
Codes: L - local, C - connected, S - static, R - RIP, M - mobile, B - BGP
D - EIGRP, EX - EIGRP external, O - OSPF, IA - OSPF inter area
N1 - OSPF NSSA external type 1, N2 - OSPF NSSA external type 2
E1 - OSPF external type 1, E2 - OSPF external type 2, E - EGP
i - IS-IS, L1 - IS-IS level-1, L2 - IS-IS level-2, ia - IS-IS inter area
* - candidate default, U - per-user static route, o - ODR
P - periodic downloaded static route
Gateway of last resort is not set
10.0.0.0/8 is variably subnetted, 10 subnets, 2 masks
C 10.1.1.0/24 is directly connected, Vlan1
L 10.1.1.1/32 is directly connected, Vlan1
C 10.1.2.0/24 is directly connected, Serial0/0/0
L 10.1.2.1/32 is directly connected, Serial0/0/0
C 10.1.3.0/24 is directly connected, Serial0/0/1
L 10.1.3.1/32 is directly connected, Serial0/0/1
C 10.1.4.0/24 is directly connected, Serial0/1/0
L 10.1.4.1/32 is directly connected, Serial0/1/0
C 10.1.5.0/24 is directly connected, FastEthernet0/0
L 10.1.5.1/32 is directly connected, FastEthernet0/0
172.16.0.0/16 is variably subnetted, 2 subnets, 2 masks
R 172.16.0.0/16 [120/1] via 10.1.5.2, 00:00:14, FastEthernet0/0
D 172.16.10.0/24 [90/28160] via 10.1.5.2, 00:07:23, FastEthernet0/0
D 192.168.10.0/24 [90/2172416] via 10.1.3.2, 00:09:13, Serial0/0/1
[90/2172416] via 10.1.2.2, 00:09:13, Serial0/0/0
D 192.168.20.0/24 [90/2172416] via 10.1.3.2, 00:09:13, Serial0/0/1
[90/2172416] via 10.1.2.2, 00:09:13, Serial0/0/0
D 192.168.30.0/24 [90/2172416] via 10.1.4.2, 00:08:59, Serial0/1/0
D 192.168.40.0/24 [90/2172416] via 10.1.4.2, 00:08:59, Serial0/1/0
Shows the entire routing table
Corp#
show ip
eigrp toplogy
all nets the Corp router can see, including on the other side of other routers
IP-EIGRP Topology Table for AS 10/ID(10.1.5.1)
Codes: P - Passive, A - Active, U - Update, Q - Query, R - Reply,
r - Reply status
directly connected via local egress interface
P 10.1.1.0/24, 1 successors, FD is 25625600
via Connected, Vlan1
P 10.1.2.0/24, 1 successors, FD is 2169856
via Connected, Serial0/0/0
P 10.1.3.0/24, 1 successors, FD is 2169856
via Connected, Serial0/0/1
P 10.1.4.0/24, 1 successors, FD is 2169856
via Connected, Serial0/1/0
P 10.1.5.0/24, 1 successors, FD is 28160
via Connected, FastEthernet0/0
remotely connected via remote ingress ip address
P 172.16.10.0/24, 1 successors, FD is 28160
via 10.1.5.2 (28160/25600), FastEthernet0/0
P 192.168.10.0/24, 2 successors, FD is 2172416
via 10.1.3.2 (2172416/28160), Serial0/0/1
via 10.1.2.2 (2172416/28160), Serial0/0/0
P 192.168.20.0/24, 2 successors, FD is 2172416
via 10.1.3.2 (2172416/28160), Serial0/0/1
via 10.1.2.2 (2172416/28160), Serial0/0/0
P 192.168.30.0/24, 1 successors, FD is 2172416
via 10.1.4.2 (2172416/28160), Serial0/1/0
P 192.168.40.0/24, 1 successors, FD is 2172416
via 10.1.4.2 (2172416/28160), Serial0/1/0
Corp#
show ip
eigrp interfaces
local interfaces on Corp, with peer data, 5 total, including VLAN1 (0 peers, no router on this network)
IP-EIGRP interfaces for process 10
Xmit Queue Mean Pacing Time Multicast Pending
Interface Peers Un/Reliable SRTT Un/Reliable Flow Timer Routes
Vlan 0 0/0 1236 0/10 0 0
Fa0/0 1 0/0 1236 0/10 0 0
Se0/0/1 1 0/0 1236 0/10 0 0
Se0/1/0 1 0/0 1236 0/10 0 0
Se0/0/0 1 0/0 1236 0/10 0 0
Corp#
show ip
eigrp neighbors
remote interfaces on the 4 neighboring routers
IP-EIGRP neighbors for process 10
H Address Interface Hold Uptime SRTT RTO Q Seq
(sec) (ms) Cnt Num
0 10.1.2.2 Se0/0/0 14 00:54:33 40 1000 0 58
1 10.1.3.2 Se0/0/1 10 00:54:33 40 1000 0 57
2 10.1.4.2 Se0/1/0 14 00:53:38 40 1000 0 51
3 10.1.5.2 Fa0/0 11 00:52:49 40 1000 0 33
4. Compare OSPF and RIPv1
RIPv1 is distance-vector and supports only classful routing. No VLSM
OSPF is link-state and supports VLSM and classless routing
5. Know how OSPF routers become neighboars and/or adjacent
they become neighbors when they see eachother's hello packets.
area id must match, links must be on the same subnet, hello/dead timers must be the same.
OSPF only shares routes with neigbors who have also established adjacencies. NOT ALL NEIGHBORS become adjacent.
When an OSPF router first receives a hello packet, it verifies that the data in some fields matches its own locally configured information.
Should any of the checked data be different, the hello packet is discarded and not processed. The data fields verified are the Area ID,
Authentication, Network Mask (on broadcast networks), Hello Interval, Router Dead Interval, and Options fields. If this information doesn’t match,
then neighborship is stuck in the down stage.
packetpushers.net
6. Be able to configure single-area OSPF
two commands:
router ospf [process id]
network x.x.x.x y.y.y.y area z
7. Be able to verify the operation of OSPF
Corp#
show ip
protocols
Corp#
show ip
route
Corp#
show ip
ospf
Corp#
show ip
ospf database
Corp#
show ip
ospf interface
Corp#
show ip
ospf neighbor
IOS 15.1
Corp#
show ip
protocols
Routing Protocol is "ospf 132"
Outgoing update filter list for all interfaces is not set
Incoming update filter list for all interfaces is not set
Router ID 10.1.5.1
Number of areas in this router is 1. 1 normal 0 stub 0 nssa
Maximum path: 4
Routing for Networks:
10.1.0.0 0.0.255.255 area 0
Routing Information Sources:
Gateway Distance Last Update
10.1.5.1 110 00:08:51
172.16.10.1 110 00:08:51
192.168.20.1 110 00:12:53
192.168.40.1 110 00:09:35
Distance: (default is 110)
IOS 15.1
Corp#
show ip
route
10.0.0.0/8 is variably subnetted, 10 subnets, 2 masks
C 10.1.1.0/24 is directly connected, Vlan1
L 10.1.1.1/32 is directly connected, Vlan1
C 10.1.2.0/24 is directly connected, Serial0/0/0
L 10.1.2.1/32 is directly connected, Serial0/0/0
C 10.1.3.0/24 is directly connected, Serial0/0/1
L 10.1.3.1/32 is directly connected, Serial0/0/1
C 10.1.4.0/24 is directly connected, Serial0/1/0
L 10.1.4.1/32 is directly connected, Serial0/1/0
C 10.1.5.0/24 is directly connected, FastEthernet0/0
L 10.1.5.1/32 is directly connected, FastEthernet0/0
172.16.0.0/24 is subnetted, 1 subnets
O 172.16.10.0/24 [110/10] via 10.1.5.2, 00:09:09, FastEthernet0/0
O 192.168.10.0/24 [110/65] via 10.1.2.2, 00:13:11, Serial0/0/0
O 192.168.20.0/24 [110/65] via 10.1.2.2, 00:13:01, Serial0/0/0
O 192.168.30.0/24 [110/65] via 10.1.4.2, 00:09:54, Serial0/1/0
O 192.168.40.0/24 [110/65] via 10.1.4.2, 00:09:54, Serial0/1/0
IOS 15.1
Corp#
show ip
ospf
Routing Process "ospf 132" with ID 10.1.5.1
Supports only single TOS(TOS0) routes
Supports opaque LSA
SPF schedule delay 5 secs, Hold time between two SPFs 10 secs
Minimum LSA interval 5 secs. Minimum LSA arrival 1 secs
Number of external LSA 0. Checksum Sum 0x000000
Number of opaque AS LSA 0. Checksum Sum 0x000000
Number of DCbitless external and opaque AS LSA 0
Number of DoNotAge external and opaque AS LSA 0
Number of areas in this router is 1. 1 normal 0 stub 0 nssa
External flood list length 0
Area BACKBONE(0)
Number of interfaces in this area is 5
Area has no authentication
SPF algorithm executed 7 times
Area ranges are
Number of LSA 5. Checksum Sum 0x034486
Number of opaque link LSA 0. Checksum Sum 0x000000
Number of DCbitless LSA 0
Number of indication LSA 0
Number of DoNotAge LSA 0
Flood list length 0
IOS 15.1
Corp#
show ip
ospf database
OSPF Router with ID (10.1.5.1) (Process ID 132)
Router Link States (Area 0)
Link ID ADV Router Age Seq# Checksum Link count
192.168.20.1 192.168.20.1 854 0x80000006 0x00ae08 6
192.168.40.1 192.168.40.1 656 0x80000004 0x006bc6 4
10.1.5.1 10.1.5.1 612 0x8000000f 0x00ab77 8
172.16.10.1 172.16.10.1 612 0x80000003 0x00b30d 2
Net Link States (Area 0)
Link ID ADV Router Age Seq# Checksum
10.1.5.1 10.1.5.1 612 0x80000001 0x00cc34
ADV Router aka RID/Router ID, the highest IP address on the router
we are seeing three connected routers + our own router (Corp at 10.1.5.1)
IOS 15.1
Corp#
show ip
ospf interface
Vlan1 is up, line protocol is up
Internet address is 10.1.1.1/24, Area 0
Process ID 132, Router ID 10.1.5.1, Network Type BROADCAST, Cost: 1
Transmit Delay is 1 sec, State DR, Priority 1
Designated Router (ID) 10.1.5.1, Interface address 10.1.1.1
No backup designated router on this network
Timer intervals configured, Hello 10, Dead 40, Wait 40, Retransmit 5
Hello due in 00:00:08
Index 1/1, flood queue length 0
Next 0x0(0)/0x0(0)
Last flood scan length is 1, maximum is 1
Last flood scan time is 0 msec, maximum is 0 msec
Neighbor Count is 0, Adjacent neighbor count is 0
Suppress hello for 0 neighbor(s)
FastEthernet0/0 is up, line protocol is up
Internet address is 10.1.5.1/24, Area 0
Process ID 132, Router ID 10.1.5.1, Network Type BROADCAST, Cost: 1
Transmit Delay is 1 sec, State DR, Priority 1
Designated Router (ID) 10.1.5.1, Interface address 10.1.5.1
Backup Designated Router (ID) 172.16.10.1, Interface address 10.1.5.2
Timer intervals configured, Hello 10, Dead 40, Wait 40, Retransmit 5
Hello due in 00:00:07
Index 2/2, flood queue length 0
Next 0x0(0)/0x0(0)
Last flood scan length is 1, maximum is 1
Last flood scan time is 0 msec, maximum is 0 msec
Neighbor Count is 1, Adjacent neighbor count is 1
Adjacent with neighbor 172.16.10.1 (Backup Designated Router)
Suppress hello for 0 neighbor(s)
Serial0/0/1 is up, line protocol is up
Internet address is 10.1.3.1/24, Area 0
Process ID 132, Router ID 10.1.5.1, Network Type POINT-TO-POINT, Cost: 64
Transmit Delay is 1 sec, State POINT-TO-POINT,
Timer intervals configured, Hello 10, Dead 40, Wait 40, Retransmit 5
Hello due in 00:00:07
Index 3/3, flood queue length 0
Next 0x0(0)/0x0(0)
Last flood scan length is 1, maximum is 1
Last flood scan time is 0 msec, maximum is 0 msec
Neighbor Count is 1 , Adjacent neighbor count is 1
Adjacent with neighbor 192.168.20.1
Suppress hello for 0 neighbor(s)
Serial0/1/0 is up, line protocol is up
Internet address is 10.1.4.1/24, Area 0
Process ID 132, Router ID 10.1.5.1, Network Type POINT-TO-POINT, Cost: 64
Transmit Delay is 1 sec, State POINT-TO-POINT,
Timer intervals configured, Hello 10, Dead 40, Wait 40, Retransmit 5
Hello due in 00:00:07
Index 4/4, flood queue length 0
Next 0x0(0)/0x0(0)
Last flood scan length is 1, maximum is 1
Last flood scan time is 0 msec, maximum is 0 msec
Neighbor Count is 1 , Adjacent neighbor count is 1
Adjacent with neighbor 192.168.40.1
Suppress hello for 0 neighbor(s)
Serial0/0/0 is up, line protocol is up
Internet address is 10.1.2.1/24, Area 0
Process ID 132, Router ID 10.1.5.1, Network Type POINT-TO-POINT, Cost: 64
Transmit Delay is 1 sec, State POINT-TO-POINT,
Timer intervals configured, Hello 10, Dead 40, Wait 40, Retransmit 5
Hello due in 00:00:07
Index 5/5, flood queue length 0
Next 0x0(0)/0x0(0)
Last flood scan length is 1, maximum is 1
Last flood scan time is 0 msec, maximum is 0 msec
Neighbor Count is 1 , Adjacent neighbor count is 1
Adjacent with neighbor 192.168.20.1
Suppress hello for 0 neighbor(s)
IOS 15.1
Corp#
show ip
ospf neighbor
Neighbor ID Pri State Dead Time Address Interface
192.168.20.1 0 FULL/ - 00:00:31 10.1.3.2 Serial0/0/1
192.168.40.1 0 FULL/ - 00:00:33 10.1.4.2 Serial0/1/0
192.168.20.1 0 FULL/ - 00:00:31 10.1.2.2 Serial0/0/0
172.16.10.1 1 FULL/BDR 00:00:32 10.1.5.2 FastEthernet0/0
Flashcards
Chapter 9 Written Lab 9.0
1. What four routed protocols are supported by EIGRP?
IPX, IPv4, IPv6, AppleTalk
2. When is redistribution required for EIGRP?
when there are multiple autonomous systems
redistribution is required when more than one EIGRP session or process is running and they are identified with different ASNs.
redistribution shares toplogy information between EIGRP sessions
3. What command would be used to enable EIGRP with an autonmous system number of 300?
router eigrp 300
4. What command will tell EIGRP that it is connected to network 172.10.0.0?
network 172.10.0.0
5. What type of EIGRP interface will neither send nor receive Hello packets?
passive-interface s0/0
6. Write the command that will enable OSPF process 101 on a router
router ospf 101
7. Write the command that will display details of all OSFP routing processes enabled on a router
show ip ospf
8. Write the command that will display interface-specific OSPF information
show ip ospf interface
9. Write the command that will display all OSPF neighbors
show ip ospf neighbor
10. Write the command that will display all different OSPF route types that are currently known by the router
show ip route ospf
Chapter 9 Hands-On Labs
Build the network and configure interfaces
LabA(config)#
int f0/0
LabA(config-if)#
ip addr 172.16.10.1 255.255.255.0
LabA(config-if)#
no shut
LabB(config)#
int f0/0
LabB(config-if)#
ip addr 172.16.10.2 255.255.255.0
LabB(config-if)#
no shut
LabB(config-if)#
int s0/0/0
LabB(config-if)#
ip addr 172.16.20.1 255.255.255.0
LabB(config-if)#
no shut
LabC(config)#
int f0/0
LabC(config-if)#
ip addr 172.16.30.1 255.255.255.0
LabC(config-if)#
no shut
LabC(config-if)#
int s0/0/0
LabC(config-if)#
ip addr 172.16.20.2 255.255.255.0
LabC(config-if)#
no shut
LabC(config-if)#
int s0/0/1
LabC(config-if)#
ip addr 172.16.40.1 255.255.255.0
LabC(config-if)#
no shut
LabD(config)#
int s0/0/0
LabD(config-if)#
ip addr 172.16.40.2 255.255.255.0
LabD(config-if)#
no shut
LabD(config-if)#
int f0/0
LabD(config-if)#
ip addr 172.16.50.1 255.255.255.0
LabD(config-if)#
no shut
9.1 - Configure and Verfiy EIGRP
configure EIGRP on all 4 routers and observe results
LabA
LabA(config)#
router eigrp 100
LabA(config-router)#
net 172.16.0.0
[no output]
LabA#
show ip eigrp neighbors
IP-EIGRP neighbors for process 100
LabA#
show ip eigrp topology
IP-EIGRP Topology Table for AS 100/ID(172.16.10.1)
Codes: P - Passive, A - Active, U - Update, Q - Query, R - Reply,
r - Reply status
P 172.16.10.0/24, 1 successors, FD is 28160
via Connected, FastEthernet0/0
LabA#
show ip eigrp interfaces
IP-EIGRP interfaces for process 100
Xmit Queue Mean Pacing Time Multicast Pending
Interface Peers Un/Reliable SRTT Un/Reliable Flow Timer Routes
Fa0/0 0 0/0 1236 0/10 0 0
no neighbors at this point since EIGRP is only active on this router. One successor AKA route, which is the connection out of this router.
But note that we have no information about what's on the other side of that link
LabB
LabB(config)#
router eigrp 100
LabB(config-router)#
net 172.16.0.0
%DUAL-5-NBRCHANGE: IP-EIGRP 100:
Neighbor 172.16.10.1 (FastEthernet0/0) is up: new adjacency
LabB#
show ip eigrp neighbors
IP-EIGRP neighbors for process 100
H Address Interface Hold Uptime SRTT RTO Q Seq
(sec) (ms) Cnt Num
0 172.16.10.1 Fa0/0 12 00:00:14 40 1000 0 1
LabB#
show ip eigrp topology
IP-EIGRP Topology Table for AS 100/ID(172.16.20.1)
Codes: P - Passive, A - Active, U - Update, Q - Query, R - Reply,
r - Reply status
P 172.16.10.0/24, 1 successors, FD is 28160
via Connected, FastEthernet0/0
P 172.16.20.0/24, 1 successors, FD is 2169856
via Connected, Serial0/0/0
LabB#
show ip eigrp interfaces
IP-EIGRP interfaces for process 100
Xmit Queue Mean Pacing Time Multicast Pending
Interface Peers Un/Reliable SRTT Un/Reliable Flow Timer Routes
Fa0/0 1 0/0 1236 0/10 0 0
Se0/0/0 0 0/0 1236 0/10 0 0
We can see a neighbor at .1
We now have two paths out of this router. Left to neighbor. Exit at right is available as successor(route), but again we have no info about
what is on the other side, since that router has no EIGRP yet (s0/0/0 has no peers, but is an EIGRP interface)
LabC
LabC(config)#
router eigrp 100
LabC(config-router)#
net 172.16.0.0
%DUAL-5-NBRCHANGE: IP-EIGRP 100:
Neighbor 172.16.20.1 (Serial0/0/0) is up: new adjacency
LabC#
show ip eigrp neighbors
IP-EIGRP neighbors for process 100
H Address Interface Hold Uptime SRTT RTO Q Seq
(sec) (ms) Cnt Num
0 172.16.20.1 Se0/0/0 12 00:00:25 40 1000 0 8
LabC#
show ip eigrp toplogy
IP-EIGRP Topology Table for AS 100/ID(172.16.40.1)
Codes: P - Passive, A - Active, U - Update, Q - Query, R - Reply,
r - Reply status
P 172.16.10.0/24, 1 successors, FD is 2172416
via 172.16.20.1 (2172416/28160), Serial0/0/0
P 172.16.20.0/24, 1 successors, FD is 2169856
via Connected, Serial0/0/0
P 172.16.30.0/24, 1 successors, FD is 28160
via Connected, FastEthernet0/0
P 172.16.40.0/24, 1 successors, FD is 2169856
via Connected, Serial0/0/1
LabC#
show ip eigrp interfaces
IP-EIGRP interfaces for process 100
Xmit Queue Mean Pacing Time Multicast Pending
Interface Peers Un/Reliable SRTT Un/Reliable Flow Timer Routes
Fa0/0 0 0/0 1236 0/10 0 0
Se0/0/0 1 0/0 1236 0/10 0 0
Se0/0/1 0 0/0 1236 0/10 0 0
.1 router B interface is now a neighbor.
LabC topology shows the 3 direct connected networks AND the network on the other side of LabB since LabB is our EIGRP neighbor
3 eigrp interfaces:
Fa0/0 is ours at LabC- no peers bc there is no eigrp router on the other end
s0/0/0 is our interface out left to LabB which is an EIGRP peer
s0/0/1 is our interface out right which does not see an EIGRP peer but does put that net 172.16.40.0 in our topology
LabD
LabD(config)#
router eigrp 100
LabD(config-router)#
net 172.16.0.0
%DUAL-5-NBRCHANGE: IP-EIGRP 100:
Neighbor 172.16.40.1 (Serial0/0/0) is up: new adjacency
LabD#
show ip eigrp neighbors
IP-EIGRP neighbors for process 100
H Address Interface Hold Uptime SRTT RTO Q Seq
(sec) (ms) Cnt Num
0 172.16.40.1 Se0/0/0 11 00:00:14 40 1000 0 6
LabD#
show ip eigrp topology
IP-EIGRP Topology Table for AS 100/ID(172.16.50.1)
Codes: P - Passive, A - Active, U - Update, Q - Query, R - Reply,
r - Reply status
P 172.16.10.0/24, 1 successors, FD is 2684416
via 172.16.40.1 (2684416/2172416), Serial0/0/0
P 172.16.20.0/24, 1 successors, FD is 2681856
via 172.16.40.1 (2681856/2169856), Serial0/0/0
P 172.16.30.0/24, 1 successors, FD is 2172416
via 172.16.40.1 (2172416/28160), Serial0/0/0
P 172.16.40.0/24, 1 successors, FD is 2169856
via Connected, Serial0/0/0
P 172.16.50.0/24, 1 successors, FD is 28160
via Connected, FastEthernet0/0
LabD#
show ip eigrp interfaces
IP-EIGRP interfaces for process 100
Xmit Queue Mean Pacing Time Multicast Pending
Interface Peers Un/Reliable SRTT Un/Reliable Flow Timer Routes
Fa0/0 0 0/0 1236 0/10 0 0
Se0/0/0 1 0/0 1236 0/10 0 0
LabC to our left is now a neighbor at 172.16.40.1
toplogy shows a route out to the right (no router on that end)
a route to the left to LabC .40.0
the .10.0, .20.0, and .30.0 networks via info from LabC
2 eigrp interfaces-
fa0/0 out to the right
s0/0/0 out left to LabC
Time to remove EIGRP from all four routers to prepare for the OSPF lab next,
since EIGRP has a lower AD than OSPF
LabA(config)#
no router eigrp 100
LabB(config)#
no router eigrp 100
LabC(config)#
no router eigrp 100
LabD(config)#
no router eigrp 100
9.2 - Enabling the OSPF Process
9.3 - Configuring OSPF Interfaces
9.4 - Verifying OSPF Operation
LabA
LabA(config)#
router ospf 100
LabA(config-router)#
net 172.16.10.1 0.0.0.0 area 0
[no output]
LabA#
show ip ospf neighbor
[no output]
LabA#
show ip ospf database
OSPF Router with ID (172.16.10.1) (Process ID 100)
Router Link States (Area 0)
Link ID ADV Router Age Seq# Checksum Link count
172.16.10.1 172.16.10.1 44 0x80000001 0x00b24b 1
LabA#
show ip ospf interface
FastEthernet0/0 is up, line protocol is up
Internet address is 172.16.10.1/24, Area 0
Process ID 100, Router ID 172.16.10.1, Network Type BROADCAST, Cost: 1
Transmit Delay is 1 sec, State DR, Priority 1
Designated Router (ID) 172.16.10.1, Interface address 172.16.10.1
No backup designated router on this network
Timer intervals configured, Hello 10, Dead 40, Wait 40, Retransmit 5
Hello due in 00:00:08
Index 1/1, flood queue length 0
Next 0x0(0)/0x0(0)
Last flood scan length is 1, maximum is 1
Last flood scan time is 0 msec, maximum is 0 msec
Neighbor Count is 0, Adjacent neighbor count is 0
Suppress hello for 0 neighbor(s)
we're including this router's interface 172.16.10.1 in our ospf area 0
fa0/0 now registers as an ospf interface
the ospf database includes data about this link only.... LabA is counting itself(10.1) as ADVERTISTING router?
the designated router is .1 LabA
LabB
LabB(config)#
router ospf 101
LabB(config-router)#
net 172.16.10.2 0.0.0.0 area 0
LabB(config-router)#
net 172.16.20.1 0.0.0.0 area 0
01:26:36: %OSPF-5-ADJCHG: Process 101, Nbr 172.16.10.1
on FastEthernet0/0 from LOADING to FULL, Loading Done
LabB#
show ip ospf neighbor
Neighbor ID Pri State Dead Time Address Interface
172.16.10.1 1 FULL/DR 00:00:33 172.16.10.1
LabB#
show ip ospf database
OSPF Router with ID (172.16.20.1) (Process ID 101)
Router Link States (Area 0)
Link ID ADV Router Age Seq# Checksum Link count
172.16.10.1 172.16.10.1 145 0x80000002 0x0067cd 1
172.16.20.1 172.16.20.1 32 0x80000003 0x006e8f 2
Net Link States (Area 0)
Link ID ADV Router Age Seq# Checksum
172.16.10.1 172.16.10.1 145 0x80000001 0x00953d
LabB#
show ip ospf interface
FastEthernet0/0 is up, line protocol is up
Internet address is 172.16.10.2/24, Area 0
Process ID 101, Router ID 172.16.20.1, Network Type BROADCAST, Cost: 1
Transmit Delay is 1 sec, State BDR, Priority 1
Designated Router (ID) 172.16.10.1, Interface address 172.16.10.1
Backup Designated Router (ID) 172.16.20.1, Interface address 172.16.10.2
Timer intervals configured, Hello 10, Dead 40, Wait 40, Retransmit 5
Hello due in 00:00:03
Index 1/1, flood queue length 0
Next 0x0(0)/0x0(0)
Last flood scan length is 1, maximum is 1
Last flood scan time is 0 msec, maximum is 0 msec
Neighbor Count is 1, Adjacent neighbor count is 1
Adjacent with neighbor 172.16.10.1 (Designated Router)
Suppress hello for 0 neighbor(s)
Serial0/0/0 is up, line protocol is up
Internet address is 172.16.20.1/24, Area 0
Process ID 101, Router ID 172.16.20.1, Network Type POINT-TO-POINT, Cost: 64
Transmit Delay is 1 sec, State POINT-TO-POINT,
Timer intervals configured, Hello 10, Dead 40, Wait 40, Retransmit 5
Hello due in 00:00:04
Index 2/2, flood queue length 0
Next 0x0(0)/0x0(0)
Last flood scan length is 1, maximum is 1
Last flood scan time is 0 msec, maximum is 0 msec
Suppress hello for 0 neighbor(s)
We've include the two interfaces on this router in the OSPF area
and can now see Router A's interface 10.1 to the left as a neighbor in the area
the "OSPF Database" now shows two links 20.1(local) and 10.1(neighbor) as 'router link states'.
"ADV Router" means advertising router for the two links. The link address is used as the advertising router.
database shows "Net Link States" category with one entry- 172.16.10.1 which is the address of neighbor router to our left
we have two local OSPF interfaces- f0/0 and s0/0/0
LabC
LabC(config)#
router ospf 102
LabC(config-router)#
net 172.16.20.2 0.0.0.0 area 0
LabC(config-router)#
net 172.16.30.1 0.0.0.0 area 0
LabC(config-router)#
net 172.16.40.1 0.0.0.0 area 0
01:33:54: %OSPF-5-ADJCHG: Process 102, Nbr 172.16.20.1
on Serial0/0/0 from LOADING to FULL, Loading Done
LabC#
show ip ospf neighbor
Neighbor ID Pri State Dead Time Address Interface
172.16.20.1 0 FULL/ - 00:00:30 172.16.20.1 Serial0/0/0
LabC#
show ip ospf database
OSPF Router with ID (172.16.40.1) (Process ID 102)
Router Link States (Area 0)
Link ID ADV Router Age Seq# Checksum Link count
172.16.10.1 172.16.10.1 542 0x80000002 0x0067cd 1
172.16.20.1 172.16.20.1 90 0x80000004 0x00a551 3
172.16.40.1 172.16.40.1 37 0x80000004 0x00e47c 4
Net Link States (Area 0)
Link ID ADV Router Age Seq# Checksum
172.16.10.1 172.16.10.1 542 0x80000001 0x00953d
LabC#
show ip ospf interface
Serial0/0/0 is up, line protocol is up
Internet address is 172.16.20.2/24, Area 0
Process ID 102, Router ID 172.16.40.1, Network Type POINT-TO-POINT, Cost: 64
Transmit Delay is 1 sec, State POINT-TO-POINT,
Timer intervals configured, Hello 10, Dead 40, Wait 40, Retransmit 5
Hello due in 00:00:01
Index 1/1, flood queue length 0
Next 0x0(0)/0x0(0)
Last flood scan length is 1, maximum is 1
Last flood scan time is 0 msec, maximum is 0 msec
Neighbor Count is 1 , Adjacent neighbor count is 1
Adjacent with neighbor 172.16.20.1
Suppress hello for 0 neighbor(s)
FastEthernet0/0 is up, line protocol is up
Internet address is 172.16.30.1/24, Area 0
Process ID 102, Router ID 172.16.40.1, Network Type BROADCAST, Cost: 1
Transmit Delay is 1 sec, State DR, Priority 1
Designated Router (ID) 172.16.40.1, Interface address 172.16.30.1
No backup designated router on this network
Timer intervals configured, Hello 10, Dead 40, Wait 40, Retransmit 5
Hello due in 00:00:02
Index 2/2, flood queue length 0
Next 0x0(0)/0x0(0)
Last flood scan length is 1, maximum is 1
Last flood scan time is 0 msec, maximum is 0 msec
Neighbor Count is 0, Adjacent neighbor count is 0
Suppress hello for 0 neighbor(s)
Serial0/0/1 is up, line protocol is up
Internet address is 172.16.40.1/24, Area 0
Process ID 102, Router ID 172.16.40.1, Network Type POINT-TO-POINT, Cost: 64
Transmit Delay is 1 sec, State POINT-TO-POINT,
Timer intervals configured, Hello 10, Dead 40, Wait 40, Retransmit 5
Hello due in 00:00:08
Index 3/3, flood queue length 0
Next 0x0(0)/0x0(0)
Last flood scan length is 1, maximum is 1
Last flood scan time is 0 msec, maximum is 0 msec
Suppress hello for 0 neighbor(s)
we include the three nets conneted to labC in the area.. 20.0, 30.0, and 40.0
link to our left, 20.1 is visible as "Neighbor"
OSPF Database-
Router Link States are
10.1(Router A)
20.1(Router B)
40.1(Router C)(This router)
Net Link States
10.1(Router A)... why does only Router A show here?
Reference- router link state vs net link state
Router Link States are type 1 LSAs. It lists all the routers in the area and the number of interfaces. 40.1 has 4 interfaces
Net Link States are the multi-access networks (Type 2 LSAs). The ADV (advertising router) is the DR.
LabD
LabD(config)#
router ospf 103
LabD(config-router)#
net 172.16.40.2 0.0.0.0 area 0
LabD(config-router)#
net 172.16.50.1 0.0.0.0 area 0
01:37:11: %OSPF-5-ADJCHG: Process 103, Nbr 172.16.40.1
on Serial0/0/0 from LOADING to FULL, Loading Done
LabD#
show ip ospf neighbor
Neighbor ID Pri State Dead Time Address Interface
172.16.40.1 0 FULL/ - 00:00:32 172.16.40.1 Serial0/0/0
LabD#
show ip ospf database
OSPF Router with ID (172.16.50.1) (Process ID 103)
Router Link States (Area 0)
Link ID ADV Router Age Seq# Checksum Link count
172.16.10.1 172.16.10.1 785 0x80000002 0x0067cd 1
172.16.20.1 172.16.20.1 333 0x80000004 0x00a551 3
172.16.40.1 172.16.40.1 111 0x80000005 0x00013b 5
172.16.50.1 172.16.50.1 53 0x80000003 0x001023 3
Net Link States (Area 0)
Link ID ADV Router Age Seq# Checksum
172.16.10.1 172.16.10.1 785 0x80000001 0x00953d
LabD#
show ip ospf interface
Serial0/0/0 is up, line protocol is up
Internet address is 172.16.40.2/24, Area 0
Process ID 103, Router ID 172.16.50.1, Network Type POINT-TO-POINT, Cost: 64
Transmit Delay is 1 sec, State POINT-TO-POINT,
Timer intervals configured, Hello 10, Dead 40, Wait 40, Retransmit 5
Hello due in 00:00:01
Index 1/1, flood queue length 0
Next 0x0(0)/0x0(0)
Last flood scan length is 1, maximum is 1
Last flood scan time is 0 msec, maximum is 0 msec
Neighbor Count is 1 , Adjacent neighbor count is 1
Adjacent with neighbor 172.16.40.1
Suppress hello for 0 neighbor(s)
FastEthernet0/0 is up, line protocol is up
Internet address is 172.16.50.1/24, Area 0
Process ID 103, Router ID 172.16.50.1, Network Type BROADCAST, Cost: 1
Transmit Delay is 1 sec, State WAITING, Priority 1
No designated router on this network
No backup designated router on this network
Timer intervals configured, Hello 10, Dead 40, Wait 40, Retransmit 5
Hello due in 00:00:04
Index 2/2, flood queue length 0
Next 0x0(0)/0x0(0)
Last flood scan length is 1, maximum is 1
Last flood scan time is 0 msec, maximum is 0 msec
Neighbor Count is 0, Adjacent neighbor count is 0
Suppress hello for 0 neighbor(s)
observations
the OSPF databases now match across all 4 routers.
NOTE that this is a database of routers, identified by
router ID. It is not a topology that lists routers AND routes,
like in the "equivalent" eigrp command.show eigrp topology
----------------------------------------------------------------------------------
PAUSE- a tale of a misconfigured network
After a 9 month hiatus, I am reviewing this book and have made it back to Chapter 9. I'm studing this webpage, working thorough the OSPF configurations
described above, and I get stuck on the concept of "link count" under "Router Link States" found in the output of show ip ospf database
The structure of the notes above is helpful, because I was tracking the state of each router BEFORE i made changes to the subsquent router. But just to be sure,
today I decided to recreate the topology, then configure each router one at a time, noting the results as I went.
And I ran into some problems.
Here is the original topology:
And today's recreated toplogy:
After replicating the toplogy and programming the IP addresses on each router, I started on configurations, just like before:
LabA
LabA(config)#
router ospf 100
LabA(config-router)#
net 172.16.10.1 0.0.0.0 area 0
[no output]
LabA#
show ip ospf neighbor
[no output]
LabA#
show ip ospf database
OSPF Router with ID (172.16.10.1) (Process ID 100)
Router Link States (Area 0)
Link ID ADV Router Age Seq# Checksum Link count
172.16.10.1 172.16.10.1 44 0x80000001 0x00b24b 1
LabA#
show ip ospf interface
FastEthernet0/0 is up, line protocol is up
Internet address is 172.16.10.1/24, Area 0
Process ID 100, Router ID 172.16.10.1, Network Type BROADCAST, Cost: 1
Transmit Delay is 1 sec, State DR, Priority 1
Designated Router (ID) 172.16.10.1, Interface address 172.16.10.1
No backup designated router on this network
Timer intervals configured, Hello 10, Dead 40, Wait 40, Retransmit 5
Hello due in 00:00:08
Index 1/1, flood queue length 0
Next 0x0(0)/0x0(0)
Last flood scan length is 1, maximum is 1
Last flood scan time is 0 msec, maximum is 0 msec
Neighbor Count is 0, Adjacent neighbor count is 0
Suppress hello for 0 neighbor(s)
good so far.... On to LabB router
LabB
LabB(config)#
router ospf 101
LabB(config-router)#
net 172.16.10.2 0.0.0.0 area 0
LabB(config-router)#
net 172.16.20.1 0.0.0.0 area 0
01:26:36: %OSPF-5-ADJCHG: Process 101, Nbr 172.16.10.1
on FastEthernet0/0 from LOADING to FULL, Loading Done
LabB#
show ip ospf neighbor
Neighbor ID Pri State Dead Time Address Interface
172.16.10.1 1 FULL/DR 00:00:33 172.16.10.1
LabB#
show ip ospf database
OSPF Router with ID (172.16.20.1) (Process ID 101)
Router Link States (Area 0)
Link ID ADV Router Age Seq# Checksum Link count
172.16.10.1 172.16.10.1 145 0x80000002 0x0067cd 1
172.16.20.1 172.16.20.1 32 0x80000003 0x006e8f 2
Net Link States (Area 0)
Link ID ADV Router Age Seq# Checksum
172.16.10.1 172.16.10.1 145 0x80000001 0x00953d
LabB#
show ip ospf interface
FastEthernet0/0 is up, line protocol is up
Internet address is 172.16.10.2/24, Area 0
Process ID 101, Router ID 172.16.20.1, Network Type BROADCAST, Cost: 1
Transmit Delay is 1 sec, State BDR, Priority 1
Designated Router (ID) 172.16.10.1, Interface address 172.16.10.1
Backup Designated Router (ID) 172.16.20.1, Interface address 172.16.10.2
Timer intervals configured, Hello 10, Dead 40, Wait 40, Retransmit 5
Hello due in 00:00:03
Index 1/1, flood queue length 0
Next 0x0(0)/0x0(0)
Last flood scan length is 1, maximum is 1
Last flood scan time is 0 msec, maximum is 0 msec
Neighbor Count is 1, Adjacent neighbor count is 1
Adjacent with neighbor 172.16.10.1 (Designated Router)
Suppress hello for 0 neighbor(s)
Serial0/0/0 is up, line protocol is up
Internet address is 172.16.20.1/24, Area 0
Process ID 101, Router ID 172.16.20.1, Network Type POINT-TO-POINT, Cost: 64
Transmit Delay is 1 sec, State POINT-TO-POINT,
Timer intervals configured, Hello 10, Dead 40, Wait 40, Retransmit 5
Hello due in 00:00:04
Index 2/2, flood queue length 0
Next 0x0(0)/0x0(0)
Last flood scan length is 1, maximum is 1
Last flood scan time is 0 msec, maximum is 0 msec
Suppress hello for 0 neighbor(s)
still looks good; same as before.... On to LabC router
LabC
LabC(config)#
router ospf 102
LabC(config-router)#
net 172.16.20.2 0.0.0.0 area 0
LabC(config-router)#
net 172.16.30.1 0.0.0.0 area 0
LabC(config-router)#
net 172.16.40.1 0.0.0.0 area 0
01:33:54: %OSPF-5-ADJCHG: Process 102, Nbr 172.16.20.1
on Serial0/0/0 from LOADING to FULL, Loading Done
LabC#
show ip ospf neighbor
[no output]
And here is where I ran into trouble. The show ip ospf neighbor command returns nothing. How can
that be?
After awhile I realized it is due to a misconfiguration in the topology.
For Lab C, I programmed the interfaces as follows:
LabC(config)#
int f0/0
LabC(config-if)#
ip addr 172.16.30.1 255.255.255.0
LabC(config-if)#
no shut
LabC(config-if)#
int s0/0/0
LabC(config-if)#
ip addr 172.16.20.2 255.255.255.0
LabC(config-if)#
no shut
LabC(config-if)#
int s0/0/1
LabC(config-if)#
ip addr 172.16.40.1 255.255.255.0
LabC(config-if)#
no shut
and again here is the topology for that router:
but here is what it SHOULD HAVE looked like (as it did the first time I built it)
S0/0/0 and S0/0/1 are swapped. When I gave the IP 172.16.20.2 to s/0/0/0, thinking that was the interface on the left side
which faces Lab B, I was actually giving 172.16.20.2 to the right side, facing LabC (which has no OSPF configs yet.)
Since the left side got got the IP intended for the right side which was 172.16.40.1
the inverse also occured-
the right side got the IP intended for the left which was 172.16.20.2
LabC left side should have been
s0/0/0 with 20.2
and LabC right side should have been
s0/0/1 with 40.1
The correct IPs were mapped to the correct interfaces. But the mistake happened before I even programmed them.
When I made the connections from LabB to LabC and from LabD to LabC, I plugged then into the wrong ports.
Interestingly.. not only is this causing OSPF to not see B as a neighbor from C.. but B and C cannot ping eachother either.
@B the config is 172.16.20.1/24 @ S0/0/0
@C the config is 172.16.40.1/24 @ S/0/0/1
meaning they are not even on the same network! But the system is not throwing any errors or bringing it to my attention.
It just fails to connect.
To correct the issue, I simply deleted those two links and re-created them. Worth noting, I used the auto select cable here,
which does not ask which interface you want to use when attaching. Earlier I must have plugged the right side first, and
auto select plugged into 0/0/0.
This time I plugged into left side first.
Now LabC OSPF data is reading out correctly...
LabC
LabC(config)#
router ospf 102
LabC(config-router)#
net 172.16.20.2 0.0.0.0 area 0
LabC(config-router)#
net 172.16.30.1 0.0.0.0 area 0
LabC(config-router)#
net 172.16.40.1 0.0.0.0 area 0
01:33:54: %OSPF-5-ADJCHG: Process 102, Nbr 172.16.20.1
on Serial0/0/0 from LOADING to FULL, Loading Done
LabC#
show ip ospf neighbor
Neighbor ID Pri State Dead Time Address Interface
172.16.20.1 0 FULL/ - 00:00:30 172.16.20.1 Serial0/0/0
LabC#
show ip ospf database
OSPF Router with ID (172.16.40.1) (Process ID 102)
Router Link States (Area 0)
Link ID ADV Router Age Seq# Checksum Link count
172.16.10.1 172.16.10.1 542 0x80000002 0x0067cd 1
172.16.20.1 172.16.20.1 90 0x80000004 0x00a551 3
172.16.40.1 172.16.40.1 37 0x80000004 0x00e47c 4
Net Link States (Area 0)
Link ID ADV Router Age Seq# Checksum
172.16.10.1 172.16.10.1 542 0x80000001 0x00953d
LabC#
show ip ospf interface
Serial0/0/0 is up, line protocol is up
Internet address is 172.16.20.2/24, Area 0
Process ID 102, Router ID 172.16.40.1, Network Type POINT-TO-POINT, Cost: 64
Transmit Delay is 1 sec, State POINT-TO-POINT,
Timer intervals configured, Hello 10, Dead 40, Wait 40, Retransmit 5
Hello due in 00:00:01
Index 1/1, flood queue length 0
Next 0x0(0)/0x0(0)
Last flood scan length is 1, maximum is 1
Last flood scan time is 0 msec, maximum is 0 msec
Neighbor Count is 1 , Adjacent neighbor count is 1
Adjacent with neighbor 172.16.20.1
Suppress hello for 0 neighbor(s)
FastEthernet0/0 is up, line protocol is up
Internet address is 172.16.30.1/24, Area 0
Process ID 102, Router ID 172.16.40.1, Network Type BROADCAST, Cost: 1
Transmit Delay is 1 sec, State DR, Priority 1
Designated Router (ID) 172.16.40.1, Interface address 172.16.30.1
No backup designated router on this network
Timer intervals configured, Hello 10, Dead 40, Wait 40, Retransmit 5
Hello due in 00:00:02
Index 2/2, flood queue length 0
Next 0x0(0)/0x0(0)
Last flood scan length is 1, maximum is 1
Last flood scan time is 0 msec, maximum is 0 msec
Neighbor Count is 0, Adjacent neighbor count is 0
Suppress hello for 0 neighbor(s)
Serial0/0/1 is up, line protocol is up
Internet address is 172.16.40.1/24, Area 0
Process ID 102, Router ID 172.16.40.1, Network Type POINT-TO-POINT, Cost: 64
Transmit Delay is 1 sec, State POINT-TO-POINT,
Timer intervals configured, Hello 10, Dead 40, Wait 40, Retransmit 5
Hello due in 00:00:08
Index 3/3, flood queue length 0
Next 0x0(0)/0x0(0)
Last flood scan length is 1, maximum is 1
Last flood scan time is 0 msec, maximum is 0 msec
Suppress hello for 0 neighbor(s)
Which brings me to the original reason I re-created this topology... I was confused about the LINK COUNTS
here:
OSPF Router with ID (172.16.40.1) (Process ID 102)
Router Link States (Area 0)
Link ID ADV Router Age Seq# Checksum Link count
172.16.10.1 172.16.10.1 542 0x80000002 0x0067cd 1
172.16.20.1 172.16.20.1 90 0x80000004 0x00a551 3
172.16.40.1 172.16.40.1 37 0x80000004 0x00e47c 4
Net Link States (Area 0)
Link ID ADV Router Age Seq# Checksum
172.16.10.1 172.16.10.1 542 0x80000001 0x00953d
The steps of recreating the lab were helpful, but this link answered the question:
Here is the output of each router's command show ip ospf interface as they are
set up one at a time.
LabA - No OSPF at B, C, or D yet
show ip ospf database
OSPF Router with ID (172.16.10.1) (Process ID 100)
Router Link States (Area 0)
Link ID ADV Router Age Seq# Checksum Link count
172.16.10.1 172.16.10.1 44 0x80000001 0x00b24b 1
LabB - No OSPF at C or D yet
show ip ospf database
OSPF Router with ID (172.16.20.1) (Process ID 101)
Router Link States (Area 0)
Link ID ADV Router Age Seq# Checksum Link count
172.16.10.1 172.16.10.1 145 0x80000002 0x0067cd 1
172.16.20.1 172.16.20.1 32 0x80000003 0x006e8f 2
Net Link States (Area 0)
Link ID ADV Router Age Seq# Checksum
172.16.10.1 172.16.10.1 145 0x80000001 0x00953d
the 20.2 interface on this router has 2 ospf links.
The left-facing out to RA, a crossover cable
The right-facing out to RC, a serial cable.
If the solution I found is correct, why is this serial link not being counted twice? The solution (I think)
is revealed after the configuration of the next router...
LabC - No OSPF at D yet
show ip ospf database
OSPF Router with ID (172.16.40.1) (Process ID 102)
Router Link States (Area 0)
Link ID ADV Router Age Seq# Checksum Link count
172.16.10.1 172.16.10.1 542 0x80000002 0x0067cd 1
172.16.20.1 172.16.20.1 90 0x80000004 0x00a551 3
172.16.40.1 172.16.40.1 37 0x80000004 0x00e47c 4
Net Link States (Area 0)
Link ID ADV Router Age Seq# Checksum
172.16.10.1 172.16.10.1 542 0x80000001 0x00953d
NOW we can see that the 20.1 link, which is the right-facing interface on LabB.. aka the router ID..
has THREE OSPF links.
Nothing changed on the left side of B. But on the right side, we now have an active OSPF router at the
other end of the link. This leads me to believe that the forum post was correct that 'serial links are counted twice',
but, more specifically, BOTH ENDS of the serial(PPP) link are counted... IF there is an OSPF router on each end.
This is backed up by the fact that LabC, OSPF id 40.1, has four OSPF links. The top-facing link to the 30
network DOES count.. even though it has no OSPF router on the other end. It counts because it's not a serial link.
The requirement of having an OSPF router on the other end for an interface to count here, only applies
to serial links. And pertains to BOTH ends of the link being counted.
In LabC's case, we have one serial at left, being counted twice. One ethernet at top, being counted once. And
one serial at right only being counted once because LabD is not active with OSPF yet.
If this is correct, then we should see Lab C's 40.1 count go to 5 after LabD is set for OSPF....
LabD - all 4 routers have OSPF
show ip ospf database
OSPF Router with ID (172.16.50.1) (Process ID 103)
Router Link States (Area 0)
Link ID ADV Router Age Seq# Checksum Link count
172.16.10.1 172.16.10.1 785 0x80000002 0x0067cd 1
172.16.20.1 172.16.20.1 333 0x80000004 0x00a551 3
172.16.40.1 172.16.40.1 111 0x80000005 0x00013b 5
172.16.50.1 172.16.50.1 53 0x80000003 0x001023 3
Net Link States (Area 0)
Link ID ADV Router Age Seq# Checksum
172.16.10.1 172.16.10.1 785 0x80000001 0x00953d
and back to LabC.....
show ip ospf database
OSPF Router with ID (172.16.40.1) (Process ID 102)
Router Link States (Area 0)
Link ID ADV Router Age Seq# Checksum Link count
172.16.10.1 172.16.10.1 1174 0x80000002 0x0067cd 1
172.16.20.1 172.16.20.1 722 0x80000004 0x00a551 3
172.16.40.1 172.16.40.1 500 0x80000005 0x00013b 5
172.16.50.1 172.16.50.1 441 0x80000003 0x001023 3
Net Link States (Area 0)
Link ID ADV Router Age Seq# Checksum
172.16.10.1 172.16.10.1 1174 0x80000001 0x00953d
Looks good! The link count for each router makes sense if you count the serial interfaces twice (one for each end).
the OSPF databases now match across all 4 routers.
NOTE that this is a database of routers, identified by
router ID. It is not a topology that lists routers AND routes, like in
the "equivalent" eigrp command show eigrp topology
Note that the .30 network is NOT represented here.
LabA#
show ip ospf database
OSPF Router with ID (172.16.10.1) (Process ID 100)
Router Link States (Area 0)
Link ID ADV Router Age Seq# Checksum Link count
172.16.10.1 172.16.10.1 1138 0x80000002 0x0067cd 1
172.16.20.1 172.16.20.1 686 0x80000004 0x00a551 3
172.16.40.1 172.16.40.1 463 0x80000005 0x00013b 5
172.16.50.1 172.16.50.1 404 0x80000003 0x001023 3
Net Link States (Area 0)
Link ID ADV Router Age Seq# Checksum
172.16.10.1 172.16.10.1 1138 0x80000001 0x00953d
LabB#
show ip ospf database
OSPF Router with ID (172.16.20.1) (Process ID 101)
Router Link States (Area 0)
Link ID ADV Router Age Seq# Checksum Link count
172.16.10.1 172.16.10.1 1151 0x80000002 0x0067cd 1
172.16.20.1 172.16.20.1 699 0x80000004 0x00a551 3
172.16.40.1 172.16.40.1 476 0x80000005 0x00013b 5
172.16.50.1 172.16.50.1 417 0x80000003 0x001023 3
Net Link States (Area 0)
Link ID ADV Router Age Seq# Checksum
172.16.10.1 172.16.10.1 1151 0x80000001 0x00953d
LabC#
show ip ospf database
OSPF Router with ID (172.16.40.1) (Process ID 102)
Router Link States (Area 0)
Link ID ADV Router Age Seq# Checksum Link count
172.16.10.1 172.16.10.1 1174 0x80000002 0x0067cd 1
172.16.20.1 172.16.20.1 722 0x80000004 0x00a551 3
172.16.40.1 172.16.40.1 500 0x80000005 0x00013b 5
172.16.50.1 172.16.50.1 441 0x80000003 0x001023 3
Net Link States (Area 0)
Link ID ADV Router Age Seq# Checksum
172.16.10.1 172.16.10.1 1174 0x80000001 0x00953d
LabD#
show ip ospf database
OSPF Router with ID (172.16.50.1) (Process ID 103)
Router Link States (Area 0)
Link ID ADV Router Age Seq# Checksum Link count
172.16.10.1 172.16.10.1 785 0x80000002 0x0067cd 1
172.16.20.1 172.16.20.1 333 0x80000004 0x00a551 3
172.16.40.1 172.16.40.1 111 0x80000005 0x00013b 5
172.16.50.1 172.16.50.1 53 0x80000003 0x001023 3
Net Link States (Area 0)
Link ID ADV Router Age Seq# Checksum
172.16.10.1 172.16.10.1 785 0x80000001 0x00953d
Below is our routing tables with OSPF data. We do see the .30 network here.
Everyone can reach it:
LabA via LabB's 10.2
LabB via LabC's 20.2
LabC via direct connection
LabD via LabC's 40.1
LabA#
show ip route
172.16.0.0/16 is variably subnetted, 6 subnets, 2 masks
C 172.16.10.0/24 is directly connected, FastEthernet0/0
L 172.16.10.1/32 is directly connected, FastEthernet0/0
O 172.16.20.0/24 [110/65] via 172.16.10.2, 00:28:03, FastEthernet0/0
O 172.16.30.0/24 [110/66] via 172.16.10.2, 00:21:35, FastEthernet0/0
O 172.16.40.0/24 [110/129] via 172.16.10.2, 00:21:25, FastEthernet0/0
O 172.16.50.0/24 [110/130] via 172.16.10.2, 00:17:40, FastEthernet0/0
LabB#
show ip route
172.16.0.0/16 is variably subnetted, 7 subnets, 2 masks
C 172.16.10.0/24 is directly connected, FastEthernet0/0
L 172.16.10.2/32 is directly connected, FastEthernet0/0
C 172.16.20.0/24 is directly connected, Serial0/0/0
L 172.16.20.1/32 is directly connected, Serial0/0/0
O 172.16.30.0/24 [110/65] via 172.16.20.2, 00:27:04, Serial0/0/0
O 172.16.40.0/24 [110/128] via 172.16.20.2, 00:26:54, Serial0/0/0
O 172.16.50.0/24 [110/129] via 172.16.20.2, 00:23:09, Serial0/0/0
LabC#
show ip route
172.16.0.0/16 is variably subnetted, 8 subnets, 2 masks
O 172.16.10.0/24 [110/65] via 172.16.20.1, 00:27:52, Serial0/0/0
C 172.16.20.0/24 is directly connected, Serial0/0/0
L 172.16.20.2/32 is directly connected, Serial0/0/0
C 172.16.30.0/24 is directly connected, FastEthernet0/0
L 172.16.30.1/32 is directly connected, FastEthernet0/0
C 172.16.40.0/24 is directly connected, Serial0/0/1
L 172.16.40.1/32 is directly connected, Serial0/0/1
O 172.16.50.0/24 [110/65] via 172.16.40.2, 00:23:36, Serial0/0/1
LabD#
show ip route
172.16.0.0/16 is variably subnetted, 7 subnets, 2 masks
O 172.16.10.0/24 [110/129] via 172.16.40.1, 00:25:20, Serial0/0/0
O 172.16.20.0/24 [110/128] via 172.16.40.1, 00:25:20, Serial0/0/0
O 172.16.30.0/24 [110/65] via 172.16.40.1, 00:25:20, Serial0/0/0
C 172.16.40.0/24 is directly connected, Serial0/0/0
L 172.16.40.2/32 is directly connected, Serial0/0/0
C 172.16.50.0/24 is directly connected, FastEthernet0/0
L 172.16.50.1/32 is directly connected, FastEthernet0/0
moving on.......
9.5 - OSPF DR and BDR Elections
EachRouter(config)#
hostname X (A, B, or C)
EachRouter(config)#
line con 0
EachRouter(config-line)#
exec-timeout 0 0
A(config)#
int f0/0
A(config-if)#
ip addr 10.1.1.1 255.255.255.0
A(config-if)#
no shut
A(config)#
router ospf 12345
A(config-router)#
net 10.1.1.0 0.0.0.255 area 0
00:23:30: %OSPF-5-ADJCHG: Process 12345, Nbr 10.1.1.3 on FastEthernet0/0 from LOADING to FULL, Loading Done
00:23:30: %OSPF-5-ADJCHG: Process 12345, Nbr 10.1.1.2 on FastEthernet0/0 from LOADING to FULL, Loading Done
A#
show ip ospf int
note this output was generated AFTER all 3 routers set for OSPF
FastEthernet0/0 is up, line protocol is up
Internet address is 10.1.1.1/24, Area 0
Process ID 12345, Router ID 10.1.1.1, Network Type BROADCAST, Cost: 1
Transmit Delay is 1 sec, State DROTHER, Priority 1
Designated Router (ID) 10.1.1.3, Interface address 10.1.1.3
Backup Designated Router (ID) 10.1.1.2, Interface address 10.1.1.2
Timer intervals configured, Hello 10, Dead 40, Wait 40, Retransmit 5
Hello due in 00:00:04
Index 1/1, flood queue length 0
Next 0x0(0)/0x0(0)
Last flood scan length is 1, maximum is 1
Last flood scan time is 0 msec, maximum is 0 msec
Neighbor Count is 2, Adjacent neighbor count is 2
Adjacent with neighbor 10.1.1.3 (Designated Router)
Adjacent with neighbor 10.1.1.2 (Backup Designated Router)
Suppress hello for 0 neighbor(s)
A(config-if)#shut
A(config-if)#
%LINK-5-CHANGED: Interface FastEthernet0/0, changed state to administratively down
%LINEPROTO-5-UPDOWN: Line protocol on Interface FastEthernet0/0, changed state to down
00:40:28: %OSPF-5-ADJCHG: Process 12345, Nbr 10.1.1.2 on FastEthernet0/0 from FULL to DOWN, Neighbor Down: Interface down or detached
00:40:28: OSPF: Build router LSA for area 0, router ID 10.1.1.1, seq 0xffffffff80000003
00:40:28: %OSPF-5-ADJCHG: Process 12345, Nbr 10.1.1.3 on FastEthernet0/0 from FULL to DOWN, Neighbor Down: Interface down or detached
00:40:28: OSPF: Build router LSA for area 0, router ID 10.1.1.1, seq 0xffffffff80000004
00:40:28: OSPF: Build router LSA for area 0, router ID 10.1.1.1, seq 0xffffffff80000004
A(config-if)#no shut
A(config-if)#
%LINK-5-CHANGED: Interface FastEthernet0/0, changed state to up
%LINEPROTO-5-UPDOWN: Line protocol on Interface FastEthernet0/0, changed state to up
00:40:48: OSPF: Build router LSA for area 0, router ID 10.1.1.1, seq 0xffffffff80000004
00:41:27: OSPF: Backup seen Event before WAIT timer on FastEthernet0/0
00:41:27: OSPF: DR/BDR election on FastEthernet0/0
00:41:27: OSPF: Elect BDR 10.1.1.2
00:41:27: OSPF: Elect DR 10.1.1.3
00:41:27: DR: 10.1.1.3 (Id) BDR: 10.1.1.2 (Id)
00:41:27: OSPF: Send DBD to 10.1.1.3 on FastEthernet0/0 seq 0x5accb8e2 opt 0x00 flag 0x7 len 32
B(config)#
int f0/0
B(config-if)#
ip addr 10.1.1.2 255.255.255.0
B(config-if)#
no shut
B(config)#
router ospf 12345
B(config-router)#
net 10.1.1.0 0.0.0.255 area 0
00:23:29: %OSPF-5-ADJCHG: Process 12345, Nbr 10.1.1.3 on FastEthernet0/0 from LOADING to FULL, Loading Done
00:23:29: %OSPF-5-ADJCHG: Process 12345, Nbr 10.1.1.1 on FastEthernet0/0 from LOADING to FULL, Loading Done
B#
show ip ospf int
note this output was generated AFTER all 3 routers set for OSPF
FastEthernet0/0 is up, line protocol is up
Internet address is 10.1.1.2/24, Area 0
Process ID 12345, Router ID 10.1.1.2, Network Type BROADCAST, Cost: 1
Transmit Delay is 1 sec, State BDR, Priority 1
Designated Router (ID) 10.1.1.3, Interface address 10.1.1.3
Backup Designated Router (ID) 10.1.1.2, Interface address 10.1.1.2
Timer intervals configured, Hello 10, Dead 40, Wait 40, Retransmit 5
Hello due in 00:00:05
Index 1/1, flood queue length 0
Next 0x0(0)/0x0(0)
Last flood scan length is 1, maximum is 1
Last flood scan time is 0 msec, maximum is 0 msec
Neighbor Count is 2, Adjacent neighbor count is 2
Adjacent with neighbor 10.1.1.1
Adjacent with neighbor 10.1.1.3 (Designated Router)
Suppress hello for 0 neighbor(s)
B#debug ip ospf adj
OSPF adjacency events debugging is on
B#
00:39:21: OSPF: DR/BDR election on FastEthernet0/0
00:39:21: OSPF: Elect BDR 10.1.1.2
00:39:21: OSPF: Elect DR 10.1.1.3
00:39:21: DR: 10.1.1.3 (Id) BDR: 10.1.1.2 (Id)
00:41:01: %OSPF-5-ADJCHG: Process 12345, Nbr 10.1.1.1 on FastEthernet0/0 from FULL to DOWN, Neighbor Down: Dead timer expired
00:41:01: %OSPF-5-ADJCHG: Process 12345, Nbr 10.1.1.1 on FastEthernet0/0 from FULL to DOWN, Neighbor Down: Interface down or detached
00:41:01: OSPF: Build router LSA for area 0, router ID 10.1.1.2, seq 0xffffffff80000003
00:41:01: OSPF: DR/BDR election on FastEthernet0/0
00:41:01: OSPF: Elect BDR 10.1.1.2
00:41:01: OSPF: Elect DR 10.1.1.3
C(config)#
int f0/0
C(config-if)#
ip addr 10.1.1.3 255.255.255.0
C(config-if)#
no shut
C(config)#
router ospf 12345
C(config-router)#
net 10.1.1.0 0.0.0.255 area 0
00:23:27: %OSPF-5-ADJCHG: Process 12345, Nbr 10.1.1.1 on FastEthernet0/0 from LOADING to FULL, Loading Done
00:23:27: %OSPF-5-ADJCHG: Process 12345, Nbr 10.1.1.2 on FastEthernet0/0 from LOADING to FULL, Loading Done
C#
show ip ospf int
note this output was generated AFTER all 3 routers set for OSPF
FastEthernet0/0 is up, line protocol is up
Internet address is 10.1.1.3/24, Area 0
Process ID 12345, Router ID 10.1.1.3, Network Type BROADCAST, Cost: 1
Transmit Delay is 1 sec, State DR, Priority 1
Designated Router (ID) 10.1.1.3, Interface address 10.1.1.3
Backup Designated Router (ID) 10.1.1.2, Interface address 10.1.1.2
Timer intervals configured, Hello 10, Dead 40, Wait 40, Retransmit 5
Hello due in 00:00:00
Index 1/1, flood queue length 0
Next 0x0(0)/0x0(0)
Last flood scan length is 1, maximum is 1
Last flood scan time is 0 msec, maximum is 0 msec
Neighbor Count is 2, Adjacent neighbor count is 2
Adjacent with neighbor 10.1.1.1
Adjacent with neighbor 10.1.1.2 (Backup Designated Router)
Suppress hello for 0 neighbor(s)
C#debug ip ospf adj
OSPF adjacency events debugging is on
C#
00:39:19: OSPF: DR/BDR election on FastEthernet0/0
00:39:19: OSPF: Elect BDR 10.1.1.2
00:39:19: OSPF: Elect DR 10.1.1.3
00:39:19: DR: 10.1.1.3 (Id) BDR: 10.1.1.2 (Id)
00:40:59: %OSPF-5-ADJCHG: Process 12345, Nbr 10.1.1.1 on FastEthernet0/0 from FULL to DOWN, Neighbor Down: Dead timer expired
00:40:59: %OSPF-5-ADJCHG: Process 12345, Nbr 10.1.1.1 on FastEthernet0/0 from FULL to DOWN, Neighbor Down: Interface down or detached
00:40:59: OSPF: Build router LSA for area 0, router ID 10.1.1.3, seq 0xffffffff80000003
00:40:59: OSPF: Build net LSA for area 0, router ID 10.1.1.3, seq 0xffffffff80000003
00:40:59: OSPF: DR/BDR election on FastEthernet0/0
00:40:59: OSPF: Elect BDR 10.1.1.2
00:40:59: OSPF: Elect DR 10.1.1.3
DR and BDR automtically set based on higest IP address
Note our network type is BROADCAST because we're using ethernet interfaces...
it would be point-to-point if using a serial connection
we want to manually overide the priority of the router. ZERO priority means it wont participate in the election process
MAX priority of 255 means no other router can beat it for DR
We'll set the priority for router A to 3.
It will beome the DR only after we shut/no shut the interface router
AND
manually power on/off the other two routers
A(config)#
int f0/0
A(config-int)#
ip ospf priority 3
A(config-int)#
shut
A(config-int)#
no shut
A#
debug ip ospf adj
B#
debug ip ospf adj
00:05:50: OSPF: DR/BDR election on FastEthernet0/0
00:05:50: OSPF: Elect BDR 10.1.1.2
00:05:50: OSPF: Elect DR 10.1.1.1
00:05:50: OSPF: Elect BDR 10.1.1.2
00:05:50: OSPF: Elect DR 10.1.1.1
00:05:50: DR: 10.1.1.1 (Id) BDR: 10.1.1.2 (Id)
00:05:50: OSPF: Send DBD to 10.1.1.1 on FastEthernet0/0 seq 0x10164ebb opt 0x00 flag 0x7 len 32
00:05:50: OSPF: Build router LSA for area 0, router ID 10.1.1.2, seq 0xffffffff80000002
00:05:52: OSPF: Rcv DBD from 10.1.1.1 on FastEthernet0/0 seq 0x20368093 opt 0x00 flag 0x7 len 32 mtu 1500 state EXSTART
00:05:52: OSPF: First DBD and we are not SLAVE
00:05:55: OSPF: Send DBD to 10.1.1.1 on FastEthernet0/0 seq 0x10164ebb opt 0x00 flag 0x7 len 32
00:05:55: OSPF: Rcv DBD from 10.1.1.1 on FastEthernet0/0 seq 0x10164ebb opt 0x00 flag 0x2 len 112 mtu 1500 state EXSTART
00:05:55: OSPF: NBR Negotiation Done. We are the MASTER
00:05:55: OSPF: Send DBD to 10.1.1.1 on FastEthernet0/0 seq 0x10164ebc opt 0x00 flag 0x3 len 52
00:05:55: OSPF: Rcv DBD from 10.1.1.1 on FastEthernet0/0 seq 0x10164ebc opt 0x00 flag 0x0 len 32 mtu 1500 state EXCHANGE
00:05:55: OSPF: Send DBD to 10.1.1.1 on FastEthernet0/0 seq 0x10164ebd opt 0x00 flag 0x1 len 32
00:05:55: OSPF: Rcv DBD from 10.1.1.1 on FastEthernet0/0 seq 0x10164ebd opt 0x00 flag 0x0 len 32 mtu 1500 state EXCHANGE
00:05:55: Exchange Done with 10.1.1.1 on FastEthernet0/0
00:05:55: OSPF: Database request to 10.1.1.1
00:05:55: OSPF: sent LS REQ packet to 10.1.1.1, length 36
00:05:55: OSPF: Rcv DBD from 10.1.1.1 on FastEthernet0/0 seq 0x10164ebd opt 0x00 flag 0x0 len 32 mtu 1500 state LOADING
00:05:55: Synchronized with with 10.1.1.1 on FastEthernet0/0, state FULL
00:05:55: %OSPF-5-ADJCHG: Process 12345, Nbr 10.1.1.1 on FastEthernet0/0 from LOADING to FULL, Loading Done
00:05:55: OSPF: Build router LSA for area 0, router ID 10.1.1.2, seq 0xffffffff80000002
C#
debug ip ospf adj
00:06:13: OSPF: DR/BDR election on FastEthernet0/0
00:06:13: OSPF: Elect BDR 10.1.1.2
00:06:13: OSPF: Elect DR 10.1.1.1
00:06:13: DR: 10.1.1.1 (Id) BDR: 10.1.1.2 (Id)
00:06:13: OSPF: Send DBD to 10.1.1.1 on FastEthernet0/0 seq 0x1cc5536d opt 0x00 flag 0x7 len 32
00:06:13: OSPF: Send DBD to 10.1.1.2 on FastEthernet0/0 seq 0x3d51ca66 opt 0x00 flag 0x7 len 32
00:06:13: OSPF: Build router LSA for area 0, router ID 10.1.1.3, seq 0xffffffff80000002
00:06:17: OSPF: Rcv DBD from 10.1.1.1 on FastEthernet0/0 seq 0x6b532eec opt 0x00 flag 0x7 len 32 mtu 1500 state EXSTART
00:06:17: OSPF: First DBD and we are not SLAVE
00:06:17: OSPF: Rcv DBD from 10.1.1.2 on FastEthernet0/0 seq 0x783110f4 opt 0x00 flag 0x7 len 32 mtu 1500 state EXSTART
00:06:17: OSPF: First DBD and we are not SLAVE
00:06:18: OSPF: Send DBD to 10.1.1.2 on FastEthernet0/0 seq 0x3d51ca66 opt 0x00 flag 0x7 len 32
00:06:18: OSPF: Send DBD to 10.1.1.1 on FastEthernet0/0 seq 0x1cc5536d opt 0x00 flag 0x7 len 32
00:06:18: OSPF: Rcv DBD from 10.1.1.2 on FastEthernet0/0 seq 0x3d51ca66 opt 0x00 flag 0x2 len 132 mtu 1500 state EXSTART
00:06:18: OSPF: NBR Negotiation Done. We are the MASTER
00:06:18: OSPF: Send DBD to 10.1.1.2 on FastEthernet0/0 seq 0x3d51ca67 opt 0x00 flag 0x3 len 52
00:06:18: OSPF: Rcv DBD from 10.1.1.1 on FastEthernet0/0 seq 0x1cc5536d opt 0x00 flag 0x2 len 132 mtu 1500 state EXSTART
00:06:18: OSPF: NBR Negotiation Done. We are the MASTER
00:06:18: OSPF: Send DBD to 10.1.1.1 on FastEthernet0/0 seq 0x1cc5536e opt 0x00 flag 0x3 len 52
00:06:18: OSPF: Rcv DBD from 10.1.1.2 on FastEthernet0/0 seq 0x3d51ca67 opt 0x00 flag 0x0 len 32 mtu 1500 state EXCHANGE
00:06:18: OSPF: Send DBD to 10.1.1.2 on FastEthernet0/0 seq 0x3d51ca68 opt 0x00 flag 0x1 len 32
00:06:18: OSPF: Rcv DBD from 10.1.1.1 on FastEthernet0/0 seq 0x1cc5536e opt 0x00 flag 0x0 len 32 mtu 1500 state EXCHANGE
00:06:18: OSPF: Send DBD to 10.1.1.1 on FastEthernet0/0 seq 0x1cc5536f opt 0x00 flag 0x1 len 32
00:06:18: OSPF: Rcv DBD from 10.1.1.2 on FastEthernet0/0 seq 0x3d51ca68 opt 0x00 flag 0x0 len 32 mtu 1500 state EXCHANGE
00:06:18: Exchange Done with 10.1.1.2 on FastEthernet0/0
00:06:18: OSPF: Database request to 10.1.1.2
00:06:18: OSPF: sent LS REQ packet to 10.1.1.2, length 48
00:06:18: OSPF: Rcv DBD from 10.1.1.1 on FastEthernet0/0 seq 0x1cc5536f opt 0x00 flag 0x0 len 32 mtu 1500 state EXCHANGE
verify on all three routers
A#
show ip ospf interface f0/0
FastEthernet0/0 is up, line protocol is up
Internet address is 10.1.1.1/24, Area 0
Process ID 12345, Router ID 10.1.1.1, Network Type BROADCAST, Cost: 1
Transmit Delay is 1 sec, State DR, Priority 3
Designated Router (ID) 10.1.1.1, Interface address 10.1.1.1
Backup Designated Router (ID) 10.1.1.2, Interface address 10.1.1.2
Timer intervals configured, Hello 10, Dead 40, Wait 40, Retransmit 5
Hello due in 00:00:09
Index 1/1, flood queue length 0
Next 0x0(0)/0x0(0)
Last flood scan length is 1, maximum is 1
Last flood scan time is 0 msec, maximum is 0 msec
Neighbor Count is 2, Adjacent neighbor count is 2
Adjacent with neighbor 10.1.1.2 (Backup Designated Router)
Adjacent with neighbor 10.1.1.3
Suppress hello for 0 neighbor(s)
A#
show ip ospf neighbor
Neighbor ID Pri State Dead Time Address Interface
10.1.1.2 1 FULL/BDR 00:00:37 10.1.1.2 FastEthernet0/0
10.1.1.3 1 FULL/DROTHER 00:00:30 10.1.1.3 FastEthernet0/0
B#
show ip ospf interface f0/0
FastEthernet0/0 is up, line protocol is up
Internet address is 10.1.1.2/24, Area 0
Process ID 12345, Router ID 10.1.1.2, Network Type BROADCAST, Cost: 1
Transmit Delay is 1 sec, State BDR, Priority 1
Designated Router (ID) 10.1.1.1, Interface address 10.1.1.1
Backup Designated Router (ID) 10.1.1.2, Interface address 10.1.1.2
Timer intervals configured, Hello 10, Dead 40, Wait 40, Retransmit 5
Hello due in 00:00:08
Index 1/1, flood queue length 0
Next 0x0(0)/0x0(0)
Last flood scan length is 1, maximum is 1
Last flood scan time is 0 msec, maximum is 0 msec
Neighbor Count is 2, Adjacent neighbor count is 2
Adjacent with neighbor 10.1.1.1 (Designated Router)
Adjacent with neighbor 10.1.1.3
Suppress hello for 0 neighbor(s)
B#
show ip ospf neighbor
Neighbor ID Pri State Dead Time Address Interface
10.1.1.1 3 FULL/DR 00:00:35 10.1.1.1 FastEthernet0/0
10.1.1.3 1 FULL/DROTHER 00:00:31 10.1.1.3 FastEthernet0/0
C#
show ip ospf interface f0/0
FastEthernet0/0 is up, line protocol is up
Internet address is 10.1.1.3/24, Area 0
Process ID 12345, Router ID 10.1.1.3, Network Type BROADCAST, Cost: 1
Transmit Delay is 1 sec, State DROTHER, Priority 1
Designated Router (ID) 10.1.1.1, Interface address 10.1.1.1
Backup Designated Router (ID) 10.1.1.2, Interface address 10.1.1.2
Timer intervals configured, Hello 10, Dead 40, Wait 40, Retransmit 5
Hello due in 00:00:06
Index 1/1, flood queue length 0
Next 0x0(0)/0x0(0)
Last flood scan length is 1, maximum is 1
Last flood scan time is 0 msec, maximum is 0 msec
Neighbor Count is 2, Adjacent neighbor count is 2
Adjacent with neighbor 10.1.1.1 (Designated Router)
Adjacent with neighbor 10.1.1.2 (Backup Designated Router)
Suppress hello for 0 neighbor(s)
C#
show ip ospf neighbor/span>
Neighbor ID Pri State Dead Time Address Interface
10.1.1.1 3 FULL/DR 00:00:35 10.1.1.1 FastEthernet0/0
10.1.1.2 1 FULL/BDR 00:00:37 10.1.1.2 FastEthernet0/0
Router1 is the DR with priority 3
still need more work to understand the output of the defbu ospf adj
Chapter 9 Review Questions
1. There are three possible routes for a router to reach a destination network:
OSPF with a metric of 782
RIPv2 with a metric of 4
EIGRP with a composite metric of 20514560
Which route will be installed in the routing table?
EIGRP because it has the lowest Administrative Distance, and AD is always used before metric
ADs are:
ExternalEIGRP 170
RIP 120
OSPF 110
IGRP 100
EIGRP 90
Static 1
Connected 0
2. Which EIGRP information is held in RAM and maintained through the use of Hello and update packets?
Neighbor table
and
toplogy table
3. Describe the process identifier that is used to run OSPF on a router
The OSPF process id is only locally significant. A random number can be selected. But it's required in order to identify
a unique OSPF database instance. You can use the same, or a different number on each router, doesnt matter.
Any number can be used from 1 to 65,535. Process ID is supplied as an argument to the command router ospf
NOT to be confused with the area number which can be any number up to 4 billion. The area id identifies a logical grouping of routers.
area id is supplied as argument to the OSPF network id and mask command
Ex:
R1(config)#
router ospf 12345
R1(config-router)#
net 10.1.1.0 0.0.0.255 area 0
4. Where are EIGRP successor routes stored?
EIGRP succesor routers are stored in the routing table. The "succesor" is the successful or primary route.
The successor route is ALSO listed in the topology table,
The feasible successor is a BACKUP route and will ONLY be listed in the topology table, unless the successor route fails,
in which case the feasible successor would become the successor
Note that my EIGRP setup doesnt seem to folow this.
CTRL-F jump to "remotely connected via remote ingress ip address"
the book states that EIGRP is automatically load-balancing our two links from R1 to corp.. is this why there is no feasible successor here?
I did some research and found that in our case, we are not using a Feasible Successor. You CAN have two Successors with equal metric, in which case EIGRP will
automatically load-balance.
But I wanted to find out what a Feasible Successor actually looks like in the EIGRP topology table..
Kevin Wallace EIGRP article
Conclusion:
EIGRP topology table wouldnt specifically say "Feasible Successor", but you would know by two routes appearing, one with a lower metric.
In my topology we have two equal-metric links and they are both considered "Successors". EIGRP uses them equally (load-balanced)
Corp#
show ip eigrp toplogy
[cut]
P 172.16.10.0/24, 1 successors, FD is 28160
via 10.1.5.2 (28160/25600), FastEthernet0/0
P 192.168.10.0/24, 2 successors, FD is 2172416
via 10.1.3.2 (2172416/28160), Serial0/0/1
via 10.1.2.2 (2172416/28160), Serial0/0/0
P 192.168.20.0/24, 2 successors, FD is 2172416
via 10.1.3.2 (2172416/28160), Serial0/0/1
via 10.1.2.2 (2172416/28160), Serial0/0/0
P 192.168.30.0/24, 1 successors, FD is 2172416
via 10.1.4.2 (2172416/28160), Serial0/1/0
P 192.168.40.0/24, 1 successors, FD is 2172416
via 10.1.4.2 (2172416/28160), Serial0/1/0
5. Which command will display all the EIGRP feasible successor routes to a known router.
show ip eigrp topology
6. Find the configuration error. You type the following into your router, but dont see any routes in the routing table?
Router(config)#
router ospf 1
Router(config-router)#
network 10.0.0.0 255.0.0.0
wrong wildcard mask
instead, could have used
0.255.255.255
or
0.0.0.255
the point is we need to specify the first octet as "allowed" into our OSPF config with a 0 mask.
The remaining bits are 'dont care' bits aka 'wildcard' aka 255
7. Which three protocols support VLSM, summarization, and discontigous networking?
RIPv2
EIGRP
OSPF
all 3 build and mainting routing tables, provide classless routing which allows VLSM, summarization, and discontigous networks
RIPv1 and IGRP build/maintain routing tables, but dont offer classless routing
8. Which are true regarding OSPF areas?
the 'backbone' is area 0
if using other areas, they all must directly connect to area 0
9. Which two network types have a designated router and a backup designated router?
Broadcast
NBMA- Non broadcast multi access. Ex: Frame Relay
network types that DO NOT use DR/BDR:
point to point
broadcast multipoint
10. You need to configure a router with a distance-vector protocol that allows classless routing. Which to use?
EIGRP is considered 'advanced distance vector' (ripv2 wasnt an option)
11. You need the IP address of the devices with which the router has established an adjacency.
Also, the retransmit interval and the queue counts for the adjacent routers need to be checked. What command will display the required information?
show ip eigrp neighbors
WRONG: show ip eigrp adjacency - there is no such command.. the word 'adjacency' is only used with debug ip OSPF adjacency
here are the possible commands for show ip eigrp and debug ip eigrp
show ip eigrp ?
interfaces IP-EIGRP interfaces
neighbors IP-EIGRP neighbors
topology IP-EIGRP Topology Table
traffic IP-EIGRP Traffic Statistics
debug ip eigrp ?
summary IP-EIGRP summary route processing
12. You cant establish an adjacency relationship on a common ethernet link between two routers. Based on the output below, what is the cause of the problem?
RouterA#
Ethernet0/0 is up, line protocol is up
Internet Address 172.16.1.2/16, Area 0
Process ID 2, Router ID 172.126.1.2, Network Type BROADCAST, Cost: 10
Transmit Delay is 1 sec, State DR, Priority 1
Designated Router (ID) 172.16.1.2, interface address 172.16.1.1.
No backup designated router on this network
Timer intervals configured, Hello 5, Dead 20, Wait 20, Retransmit 5
Router B#
Internet Address 172.16.1.1/16, Area 0
Process ID 2, Router ID 172.126.1.1, Network Type BROADCAST, Cost: 10
Transmit Delay is 1 sec, State DR, Priority 1
Designated Router (ID) 172.16.1.1, interface address 172.16.1.2.
No backup designated router on this network
Timer intervals configured, Hello 10, Dead 40, Wait 40, Retransmit 5
mismatched timer intervals
OSPF default Hello is 10 and Dead is 40... RouterA was modified
13. Which is true regarding EIGRP successor routes?
Used in the routing table
also appears in the topolgy table
may (or may not) have a backup feasabile successor
14. Which type of OSPF network will elect a backup designated router?
broadcast multi-access
non-broadcast multiaccess
types of network that will NOT elect a BDR:
point to point and brodacast multipoint (hub/spoke topology)
15. Which two commands will place network 10.2.3.0/24 into area 0?
Router(config)#
router ospf 10
Router(config-router)#
network 10.2.3.0 0.0.0.255 area 0
16. With which network type will OSPF establish router adjacencies but not perform the DR/BDR election process?
Point to point
no election process occurs, there is never a DR on point to point
17. What are three reasons for creating OSPF in a heirarchical design?
decrease routing overhead
speed up convergence
confine stability to single areas of the network
18. What is the administrative distance of OSPF?
110
19.
no auto summary
the network is considered discontigous because we have two classful network subnetted (on the left and right),
seperated by a different classful address.
if auto summarization is taking place, the routers cant determine which side is which because both sides would be summarized as
Class B, 172.16.0.0, which isnt specific enough to distinguish between the sides.
20. IF routers in a single area are configured with the same priority value, what value does a router use for the OSPF router ID in the absence of a loopback interface?
The highest IP of any PHSYICAL interface.
Trick question. Highest IP of any LOGICAL interface is an option. And is correct IF you had logical interfaces, but the question
states that any "logical interfaces are absent".
At OSPF startup, the highest IP of *any* active interface on the router becomes the OSPF router ID. If you have loopback (logical) interfaces configured,
one of them (the largest IP) will *override* the phsyical interfaces and the loopback IP becomes the RID.
Reference for which loopback (if multiple) wins:
packetpushers.net
------------------------------------------------------------------------------
END CHAPTER 9
41 hours 2-14 thru 2-28-22
original total 184 hours
14 hours review 12-26 thru 12-28-22
review total hours 46
book page 502/822
184 + 46 = 230 hours * 60 = (13,800 min) / 500 pages =
avg 28 min/page (includes reading and exercises/labs + online research)
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1. You type show running-config and get this output:
---cut---
line console 0
Exec-timeout 1 44
Password 7 098C0BQR
Login
---cut---
What do the two numbers following the exec-timeout command mean?
---cut---
line console 0
Exec-timeout 1 44
Password 7 098C0BQR
Login
---cut---
What do the two numbers following the exec-timeout command mean?
minutes and seconds
2. Which connection method for connecting to a router is considered "out-of-band"?
auxiliary
The aux port can be configured to allow a modem to connect to the router.
It lets you dial up to a remote router in order to connect to the aux port if the router is down.
This method is considered "out of band" since its not connecting via "the network"
The aux port can be configured to allow a modem to connect to the router.
It lets you dial up to a remote router in order to connect to the aux port if the router is down.
This method is considered "out of band" since its not connecting via "the network"
3. Which two commands are required when configuring SSH on your router?
ip domain-name name
username name password password
Example: Using SSH instead of Telnet
set your hostname, domain, and username
router(config)# hostname Dallas
Dallas(config)# ip domain-name Lammle.com
Dallas(config)# username Michael password 1234
generate encryption keys
Dallas(config)# crypto key generate rsa genral-keys modulus 1024
router(config)# ssh version 2
connect to the vty lines of the router
router(config)# line vty 0 1180
configure SSH and then Telnet as access protocols
router(config-line)# transport input ssh telnet
username name password password
Example: Using SSH instead of Telnet
set your hostname, domain, and username
router(config)# hostname Dallas
Dallas(config)# ip domain-name Lammle.com
Dallas(config)# username Michael password 1234
generate encryption keys
Dallas(config)# crypto key generate rsa genral-keys modulus 1024
The name for the keys will be Michael.Lammle.com
% The key modulus size is 1024 bits
% Generating 1024 bit RSA keys, keys will be non-exportable...[ok]
*June 24 19:25:30.035: %SSH-5-ENABLED: SSH 1.99 has been enabled
enable SSH version 2
router(config)# ssh version 2
connect to the vty lines of the router
router(config)# line vty 0 1180
configure SSH and then Telnet as access protocols
router(config-line)# transport input ssh telnet
4. Which command will show you wheter a DTE or a DCE cable is plugged into serial 0?
show controllers serial 0
will show whether DTE or DCE cable is connected to the interface
NOTE if it is a DTE connection you must add clocking with the clock rate command
will show whether DTE or DCE cable is connected to the interface
NOTE if it is a DTE connection you must add clocking with the clock rate command
5. Which is a correct combination of file type and default location on a Cisco router?
IOS- flash memory
startup config- NVRAM
running config- RAM
startup config- NVRAM
running config- RAM
6. You set the console password, but when you display the configuration, the password doesn't show up;
it looks like this:
[output cut]
line console 0
Exec-timeout 1 44
Password 7 098C0BQR
Login
[output cut]
What command would configure the password to be stored this way?
it looks like this:
[output cut]
line console 0
Exec-timeout 1 44
Password 7 098C0BQR
Login
[output cut]
What command would configure the password to be stored this way?
service password-encryption
7. Which command will configure all the default VTY ports on a router?
from global config mode:
line vty 0 4
will set all 5 default lines
line vty 0 4
will set all 5 default lines
8. Which command set the secret password to Cisco?
enable secret Cisco
9. If you wanted to see a message when logging into the router, which command would you use?
MOTD
10. Which prompt indicate that the router is currently in priviliged mode?
router#
11. What command do you type to save the configuration stored in RAM to NVRAM?
copy running-config startup-config
12. You try to telnet into SSFRouter from router to Corp and receive this message:
Corp#telnet SFRouter
Trying SFRouter (10.0.0.1)...Open
Password required, but none set
[Connection to SFRouter closed by foreing host]
Corp#
Which command sequence will address the problem correctly?
Corp#telnet SFRouter
Trying SFRouter (10.0.0.1)...Open
Password required, but none set
[Connection to SFRouter closed by foreing host]
Corp#
Which command sequence will address the problem correctly?
SFRouter(config)#
line vty 0 4
SFRouter(config-line)# password password1234
SFRouter(config-line)# login
SFRouter(config-line)# password password1234
SFRouter(config-line)# login
13. Which command will delete the contents of NVRAM on a router?
erase startup-config
14. What is the problem with an interface if you type
show interface serial 9
and receive the following message?
Serial0 is administratively down, line protocol is down
Serial0 is administratively down, line protocol is down
is set to 'shut' by default, fix with no shut
15. Which command displays the configurable parameters and statistics of all interfaces on a router?
show interfaces
16. If you delete the contents of NVRAM and reboot the router, what mode will you be in?
setup mode
--- System Configuration Dialog ---
Would you like to enter the initial configuration dialog? [yes/no]:
17. You type the following command into the router and receive the following output:
Router#show serial 0/0
^
% Invalid input detected at '^' marker.
Router#show serial 0/0
^
% Invalid input detected at '^' marker.
show interface serial 0/0
18. You type Router#sh ru and receive a % ambiguous command error.
Why did you receive this error?
not specific enough- there is more than one possible
show
command that starts with
ru
19. Which of the following commands will display the current
IP addressing and the layer 1 and 2 status of an interface?
show interfaces
show ip interface
GigabitEthernet0/0/0 is up, line protocol is down (disabled)
Hardware is ISR4331-3x1GE, address is 000d.bd45.db01 (bia 000d.bd45.db01)
Internet address is 1.1.1.1/16
MTU 1500 bytes, BW 1000000 Kbit, DLY 10 usec,
reliability 255/255, txload 1/255, rxload 1/255
Encapsulation ARPA, loopback not set
Keepalive not supported
Half Duplex, 1000Mbps, link type is auto, media type is Auto Select
output flow-control is on, input flow-control is on
ARP type: ARPA, ARP Timeout 04:00:00,
Last input 00:00:08, output 00:00:05, output hang never
Last clearing of "show interface" counters never
Input queue: 0/375/0 (size/max/drops); Total output drops: 0
Queueing strategy: fifo
Output queue :0/40 (size/max)
5 minute input rate 0 bits/sec, 0 packets/sec
5 minute output rate 0 bits/sec, 0 packets/sec
0 packets input, 0 bytes, 0 no buffer
Received 0 broadcasts (0 IP multicasts)
0 runts, 0 giants, 0 throttles
0 input errors, 0 CRC, 0 frame, 0 overrun, 0 ignored
0 watchdog, 1017 multicast, 0 pause input
0 input packets with dribble condition detected
0 packets output, 0 bytes, 0 underruns
0 output errors, 0 collisions, 1 interface resets
0 unknown protocol drops
0 babbles, 0 late collision, 0 deferred
0 lost carrier, 0 no carrier
0 output buffer failures, 0 output buffers swapped out
GigabitEthernet0/0/1 is administratively down, line protocol is down (disabled)
Hardware is ISR4331-3x1GE, address is 000d.bd45.db02 (bia 000d.bd45.db02)
MTU 1500 bytes, BW 1000000 Kbit, DLY 10 usec,
reliability 255/255, txload 1/255, rxload 1/255
Encapsulation ARPA, loopback not set
Keepalive not supported
output flow-control is on, input flow-control is on
ARP type: ARPA, ARP Timeout 04:00:00,
Last input 00:00:08, output 00:00:05, output hang never
Last clearing of "show interface" counters never
Input queue: 0/375/0 (size/max/drops); Total output drops: 0
Queueing strategy: fifo
Output queue :0/40 (size/max)
5 minute input rate 0 bits/sec, 0 packets/sec
5 minute output rate 0 bits/sec, 0 packets/sec
0 packets input, 0 bytes, 0 no buffer
Received 0 broadcasts (0 IP multicasts)
0 runts, 0 giants, 0 throttles
0 input errors, 0 CRC, 0 frame, 0 overrun, 0 ignored
0 watchdog, 1017 multicast, 0 pause input
0 input packets with dribble condition detected
0 packets output, 0 bytes, 0 underruns
0 output errors, 0 collisions, 1 interface resets
0 unknown protocol drops
0 babbles, 0 late collision, 0 deferred
0 lost carrier, 0 no carrier
0 output buffer failures, 0 output buffers swapped out
GigabitEthernet0/0/2 is administratively down, line protocol is down (disabled)
Hardware is ISR4331-3x1GE, address is 000d.bd45.db03 (bia 000d.bd45.db03)
MTU 1500 bytes, BW 1000000 Kbit, DLY 10 usec,
reliability 255/255, txload 1/255, rxload 1/255
Encapsulation ARPA, loopback not set
Keepalive not supported
Half Duplex, 1000Mbps, link type is auto, media type is unknown media type
output flow-control is on, input flow-control is on
ARP type: ARPA, ARP Timeout 04:00:00,
Last input 00:00:08, output 00:00:05, output hang never
Last clearing of "show interface" counters never
Input queue: 0/375/0 (size/max/drops); Total output drops: 0
Queueing strategy: fifo
Output queue :0/40 (size/max)
5 minute input rate 0 bits/sec, 0 packets/sec
5 minute output rate 0 bits/sec, 0 packets/sec
0 packets input, 0 bytes, 0 no buffer
Received 0 broadcasts (0 IP multicasts)
0 runts, 0 giants, 0 throttles
0 input errors, 0 CRC, 0 frame, 0 overrun, 0 ignored
0 watchdog, 1017 multicast, 0 pause input
0 input packets with dribble condition detected
0 packets output, 0 bytes, 0 underruns
0 output errors, 0 collisions, 1 interface resets
0 unknown protocol drops
0 babbles, 0 late collision, 0 deferred
0 lost carrier, 0 no carrier
0 output buffer failures, 0 output buffers swapped out
Vlan1 is administratively down, line protocol is down
Hardware is CPU Interface, address is 00d0.9715.9967 (bia 00d0.9715.9967)
MTU 1500 bytes, BW 100000 Kbit, DLY 1000000 usec,
reliability 255/255, txload 1/255, rxload 1/255
Encapsulation ARPA, loopback not set
ARP type: ARPA, ARP Timeout 04:00:00
Last input 21:40:21, output never, output hang never
Last clearing of "show interface" counters never
Input queue: 0/75/0/0 (size/max/drops/flushes); Total output drops: 0
Queueing strategy: fifo
Output queue: 0/40 (size/max)
5 minute input rate 0 bits/sec, 0 packets/sec
5 minute output rate 0 bits/sec, 0 packets/sec
1682 packets input, 530955 bytes, 0 no buffer
Received 0 broadcasts (0 IP multicast)
0 runts, 0 giants, 0 throttles
0 input errors, 0 CRC, 0 frame, 0 overrun, 0 ignored
563859 packets output, 0 bytes, 0 underruns
0 output errors, 23 interface resets
0 output buffer failures, 0 output buffers swapped out
show ip interface
GigabitEthernet0/0/0 is up, line protocol is down (disabled)
Internet address is 1.1.1.1/16
Broadcast address is 255.255.255.255
Address determined by setup command
MTU is 1500 bytes
Helper address is not set
Directed broadcast forwarding is disabled
Outgoing access list is not set
Inbound access list is not set
Proxy ARP is enabled
Security level is default
Split horizon is enabled
ICMP redirects are always sent
ICMP unreachables are always sent
ICMP mask replies are never sent
IP fast switching is disabled
IP fast switching on the same interface is disabled
IP Flow switching is disabled
IP Fast switching turbo vector
IP multicast fast switching is disabled
IP multicast distributed fast switching is disabled
Router Discovery is disabled
IP output packet accounting is disabled
IP access violation accounting is disabled
TCP/IP header compression is disabled
RTP/IP header compression is disabled
Probe proxy name replies are disabled
Policy routing is disabled
Network address translation is disabled
BGP Policy Mapping is disabled
Input features: MCI Check
WCCP Redirect outbound is disabled
WCCP Redirect inbound is disabled
WCCP Redirect exclude is disabled
GigabitEthernet0/0/1 is administratively down, line protocol is down (disabled)
Internet protocol processing disabled
GigabitEthernet0/0/2 is administratively down, line protocol is down (disabled)
Internet protocol processing disabled
Vlan1 is administratively down, line protocol is down
Internet protocol processing disabled
20. At which layer of the OSI model would you assume the problem is if you type
show interface serial 1 and receive the following message?
Serial 1 is down, line protocol is down
show interface serial 1 and receive the following message?
Serial 1 is down, line protocol is down
physical
if you see both interface and protocal down, it's physical
if you see serial1 is up but line protocol down, its data link- data-link keepalives are not being sent from the remote end
if you see both interface and protocal down, it's physical
if you see serial1 is up but line protocol down, its data link- data-link keepalives are not being sent from the remote end
Configuration Register
16 bits / 2 bytes... bit values from 15 to 0
uses Hexadecimal nibbles
Chapter 7 Exam Essentials - Managing a Cisco Internetwork
1. Define the Cisco router componenets
ROM
- used to start and maintain the router. Holds bootstrap, POST, mini-IOS
bootstrap
- stored in the microcode of the ROM. Finds where the IOS program is located and loads the file.
POST
- stored in the microcode of the ROM. Used to check the basic funtionality and determine which interfaces are present
ROM monitor
- stored in the microcode of the ROM. Used for manufacturing, testing, and troubleshooting
mini-IOS
- Called the RXBOOT or 'bootloader'. It's a small OS in ROM that can be used to bring up an interface and load a Cisco IOS into flash memory
-----------------------------------------------------------------------------------------------------------------------
flash memory
- EEPROM- default location of the IOS
NVRAM
-holds the router/switch configuration
not erased when the device is reloaded
configuration register
- controls how the router boots up
Tells the router to load the IOS from flash memory as well as to load the configuration from NVRAM
RAM
- used to hold packet buffers, ARP cache, routing tables and the data structures that allow the router to function.
running-config is stored in RAM
routers expand the IOS from flash into RAM at boot
2. Identify the steps in the router boot sequence
POST
bootstrap
load the IOS from flash into RAM
load the configuration file from NVRAM into RAM
running-config and the IOS are both now running in RAM
3. Understand configuration register commands and settings
0x2102 default- find the boot sequence in NVRAM
0x2101 boot from ROM
0x2142 do not load the startup-config in NVRAM. Used for password recovery
4.Perform password recovery
NOTE - this requires physical access to reboot the router
The default configuration register value is 0x2102 which tells the router to load a config stored
in NVRAM(startup-config).
To recover a password, we need to change the config register value to 0x2142 which tells the router to ignore the VRAM contents and load a 'non configured' OS.
"configurations" can be defined as any changes we make to the device: hostname, passwords, interfaces, etc
For this demo, our 4331 router is configured with the hostname 4331 and the password 1234
4331(config)#
enable secret 1234
4331#
copy run start
Destination filename [startup-config]?
Building configuration...
[OK]
Step 1. Bounce the router, then interrupt the boot sequence by performing a break.
Initializing Hardware ...
Checking for PCIe device presence...done
System integrity status: 0x610
Rom image verified correctly
System Bootstrap, Version 16.7(3r), RELEASE SOFTWARE
Copyright (c) 1994-2018 by cisco Systems, Inc.
Current image running: Boot ROM0
Last reset cause: LocalSoft
Cisco ISR4331/K9 platform with 4194304 Kbytes of main memory
no valid BOOT image found
Final autoboot attempt from default boot device...
Located isr4300-universalk9.16.06.04.SPA.bin
###############################################################
CTRL+BREAK
monitor: command "boot" aborted due to user interrupt
rommon 1 >
Step 2. We're given a ROM MONITOR prompt which allows us to change the configuration register (Cisco ISR/2600 Series commands).
rommon 1 >
confreg 0x2142
rommon 1 >
reset must reset or power cycle router to apply the change
system will ask if you want Setup Mode - that is the the generic startup message,
since we are bypassing the startup configuration. Our answer is no.--- System Configuration Dialog ---
Would you like to enter the initial configuration dialog? [yes/no]:
N + Enter
we now have full access to this non-configured OS. We can enter priviliged mode with no password.
Router>
enable
Router#
show version
Cisco IOS Software [Everest], ISR Software (X86_64_LINUX_IOSD-UNIVERSALK9-M), Version 16.6.4,RELEASE SOFTWARE (fc3)
[cut]
Configuration register is 0x2142
this verifies that our configs are not in use (no hostname in the prompt) and our config register has been changed to 2142
HERE IS THE KEY-
we are going to restore the configuration by copying the "startup-config"
into our live environment AKA the "running-config"
Router#
copy startup-config running-config
Destination filename [running-config]? Enter
695 bytes copied in 0.416 secs (1670 bytes/sec)
4331#
%SYS-5-CONFIG_I: Configured from console by console
we get our old prompt back:
4331#
Note that we DO NOT know the password required to enter privliged mode that we are currently inside of!
if you exit this prompt back out to user mode, you will not be able to get back in without the password.
We entered privileged mode from within the generic configuration. Then inserted our saved configuration 'beneath' our prompt.
This action does not kick you out of priv. mode, which will allow us to RESET the password for our saved configuration.
set the new password
4331(config)#
enable secret 0000
set the config register back to default, to point back to NVRAM on the next reboot
(you can do this from global config mode as well as rommon mode)
4331(config)#
config-register 0x2102
4331#
show version
[cut]
Configuration register is 0x2142 (will be 0x2102 at next reload)
now we can save the config with the updated password.
Two ways to do it-
4331#
write
Building configuration...
[OK]
OR
4331#
copy running-config startup-config
Destination filename [startup-config]?
Building configuration...
[OK]
reload the router and your new password will be saved into your config
4331#
reload
this feature is helpful since Cisco equipment tends to run for long stretches of time (years) and the passwords get forgotten.
Thank you to Jeremy Cioara for help on this topic
5. Back up an IOS image
we can copy a router's configuration to a TFTP server with either of these commands:
Router#
copy running-config tftp
Router#
copy startup-config tftp
to verify either of the configs before backup, we can use these commands:
Router#
show running-config
Router#
show startup-config
6. Restore or upgrade an IOS image - note we are talking about the IOS itself, not the 'configuration'
We will download the IOS file from TFTP server to flash memory on the router. Command requires the IP of the TFTP host and the filename
Before we begin we must make sure the IOS file is in the default TFTP directory on the host.
The command will not ask you where the file is on the host....
Router#
copy tftp flash
Address or name of remote host []? 1.1.1.2
Source filename []? c2800nm-advsecurityk9-mz.124.12.bin
Destination filename[c2800nm-advsecurityk9-mz.124.12.bin]? ENTER
%Warning this is a file already existing with this name
Do you want to over write [confirm] ENTER
Accessing tftp://1.1.1.2/c2800nm-advsecurityk9-mz.124-12.bin...
Loading c2800nm-advsecurityk9-mz.124-12.bin from 1.1.1.2 (via FastEthernet0/0): !!!!!!!!!!!!!!!!
!!!!!!!!!!!!!!!!!!!!!!!!!!
[OK - 21710744 bytes]
21710744 bytes copied in 82.880 secs (261954 bytes/sec)
Router#
to restore configuration:
restore from startup-config:
Router#
copy startup-config running-config
or we can restore from a backup on TFTP server
Router#
copy tftp running-config
Address or name of remote host []? 1.1.1.2
Source filename []? todd-confg
Destination filename[running-config?] ENTER
Accessing tftp://1.1.1.2/todd-confg...
Loading todd-confg from 1.1.12 (civa FastEthernet0/0): !
[OK - 776 bytes]
776 bytes copied in 9.212 secs (84 bytes/sec)
Router#
*Jan 23 12:40:00.000: %SYS-5-CONFIG_I: Configured from tftp://1.1.1.2/todd-confg by console
Router#
7. Describe best practices to prepare to back up an IOS image to a network server
Ensure you can acccess the network server, and there is adequate storage space.
Verify the file naming and path requirements
have the source IOS file in the default TFTP directory
8. Save the configuration of a router
Router#
copy running-config startup-config
9. Erase the configuration of a router
Router#
erase startup-config
10. Understand and use the Cisco IFS file system management commands
IFS = IOS File System
UNIX Based
dir
show files in a directory. Requires privliged mode. If not path is given as argument, you'll see the directory of 'flash' root.
NOTE the file paths use a URL format
R1#
dir
Directory of flash:/
3 -rw- 486899872 <no date> isr4300-universalk9.16.06.04.SPA.bin
2 -rw- 28282 <no date> sigdef-category.xml
1 -rw- 227537 <no date> sigdef-default.xml
3249049600 bytes total (2761893909 bytes free)
-------------------------------------------------------------------------------------------------------
copy
often used to backup, restore, or ugprade the IOS
first arg = source
second arg = destination
R1#
copy
source
destination
-------------------------------------------------------------------------------------------------------
more
display a text file
-------------------------------------------------------------------------------------------------------
show file
display a text file
-------------------------------------------------------------------------------------------------------
delete
remote file (may also need to use SQUEEZE to free up the space)
-------------------------------------------------------------------------------------------------------
erase/format
may delete flash drive depending on system
-------------------------------------------------------------------------------------------------------
cd/pwd
change directory / print working directory
-------------------------------------------------------------------------------------------------------
mkdir/rmdir
create / delete directories
11. Describe the value of CDP
Cisco Discovery Protocol - helps to document / troubleshoot the network
See lab 7.4
12. List the information provided by the output of
show cdp neighbors
device ID
local interface
holdtime
capabilility
platform
port ID (remote interface)
13. Understand how to establish a Telnet session with multiple routers simultaneously
Press Ctrl+Shift+6 then x to exit a telnet session without closing it
14. Identify current Telnet sessions
R1#
show sessions
15. Build a static host table on a router
R1#
ip host
host_name
ip_address
manually assigning an IP to a host name. You can apply multiple IP's to one host entry
see lab 7.6
16. Verify the host table on a router
R1#
show hosts
17. Describe the function of the ping command
Packet Internet Groper uses ICMP echo requests and replies to verify an active IP address on a network
18. Ping a vaild host ID from the correct prompt
R1#
ping 1.1.1.1
Note PING works from user or privliged mode but NOT config mode
Chapter 7 Written Lab 7.1 - IOS Management
TFTP Server Setup - network layout is not from book- I created this network to help demo the written lab
TFTP server is already created and switched on by default within the 'Server' object
Router Configuration
R1(config)#
int g0/0/1
R1(config-if)#
ip address 10.1.1.4 255.255.255.0
R1(config-if)#
no shutdown
%LINK-5-CHANGED: Interface GigabitEthernet0/0/1, changed state to up
%LINEPROTO-5-UPDOWN: Line protocol on Interface GigabitEthernet0/0/1, changed state to up
r1(config-if)#
do show ip int brief
Interface IP-Address OK? Method Status Protocol
GigabitEthernet0/0/0 unassigned YES manual administratively down down
GigabitEthernet0/0/1 192.1.1.4 YES NVRAM up up
GigabitEthernet0/0/2 unassigned YES NVRAM administratively down down
Vlan1 unassigned YES NVRAM administratively down down
Switch Configuration
SW1(config)#
int f0/1
SW1(config-if)#
no shutdown
%LINK-5-CHANGED: Interface FastEthernet0/1, changed state to up
%LINEPROTO-5-UPDOWN: Line protocol on Interface FastEthernet0/1, changed state to up
SW1(config-if)#
int f0/2
SW1(config-if)#
no shutdown
%LINK-5-CHANGED: Interface FastEthernet0/2, changed state to up
%LINEPROTO-5-UPDOWN: Line protocol on Interface FastEthernet0/2, changed state to up
Test connectivity to the server
R1#
ping 192.1.1.3
Type escape sequence to abort.
Sending 5, 100-byte ICMP Echos to 192.1.1.3, timeout is 2 seconds:
.!!!!
Success rate is 80 percent (4/5), round-trip min/avg/max = 0/1/6 ms
Find the name of the Router flash file
R1#
show flash
System flash directory:
File Length Name/status
3 486899872isr4300-universalk9.16.06.04.SPA.bin
2 28282 sigdef-category.xml
1 227537 sigdef-default.xml
[487155691 bytes used, 2761893909 available, 3249049600 total]
3.17338e+06K bytes of processor board System flash (Read/Write)
we need to paste that filename into our copy command below
1. command to copy a Cisco IOS to a TFTP server?
R1#
copy flash tftp
Source filename []? isr4300-universalk9.16.06.04.SPA.bin
Address or name of remote host []? 192.1.1.3
Destination filename [isr4300-universalk9.16.06.04.SPA.bin]? ENTER
Writing isr4300-universalk9.16.06.04.SPA.bin...!!!!!!!!!!!!!!!!
!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!
[OK - 486899872 bytes]
486899872 bytes copied in 12.364 secs (126865 bytes/sec)
the file appears on our server
2. command to copy a Cisco startup-config file to a TFTP server?
R1#
copy running-config tftp
Address or name of remote host []? 192.1.1.3
Destination filename [r1-confg]? ENTER
Writing running-config.....!!
[OK - 707 bytes]
707 bytes copied in 3 secs (235 bytes/sec)
the file appears on our server
OR
R1#
copy startup-config tftp
3. command to copy the startup-config file to DRAM?
R1#
copy startup-config running-config
the running configuration exists in DRAM
4. What is an older command that you can use to copy the startup-config file to DRAM?
R1#
config mem
(not supported by packet tracer)
5. What command can you use to see the neighbor router's IP address from your router prompt?
R1#
show cdp neighbor detail
OR
R1#
show cdp entry *
6. What command to see the hostname, local interface, platform, and remote port of a neighbor router?
R1#
show cdp neighbor
7. What keystrokes can you use to telnet into multiple devices simultaneously?
Ctrl + Shift + 6, then X
8. What command will show you your active Telnet connections to neighbor and remote devices?
R1#
show sessions
9. What command can you use to upgrade a Cisco IOS?
R1#
copy tftp flash
10. What command can you use to merge a backup configuration with the configuration in RAM?
R1#
copy tftp run
OR
R1#
copy start run
RAM = running configuration
Chapter 7 Written Lab 7.2 - Router Memory
Identify the location in a router where each of the files is stored by default:
1. Cisco IOS
flash
2. Bootstrap
ROM
3. Startup configuration
NVRAM
4. POST
ROM
5. Running configuration
RAM
6. ARP cache
RAM
7. Mini IOS
ROM
8. ROM Monitor
ROM
9. Routing tables
RAM
10. packet buffers
RAM
****dont make the mistake of thinking arp cache, routing tables, packet buffers, are stored somewhere other than RAM
they are considered part of running-config which exists in RAM
Chapter 7 Hands-on Labs
To complete these labs, we are going to need three routers and one TFTP server.
Here is the topology:
Server Configuration
ipv4 address: 193.1.1.2
subnet mask: 255.255.255.248
default gateway: 193.1.1.1
Switch Configuration
SW1#
interface range f0/1-2
SW1(config-if-range)#
no shut
Router Configurations
R1(config)#
int g0/0/0
R1(config)#
ip addr 193.1.1.9 255.255.255.248
R1(config)#
no shut
R1(config)#
int g0/0/1
R1(config)#
ip addr 193.1.1.1 255.255.255.248
R1(config)#
no shut
the server's default gateway
R2(config)#
int g0/0/0
R2(config)#
ip addr 193.1.1.10 255.255.255.248
R2(config)#
no shut
R2(config)#
int g0/0/1
R2(config)#
ip addr 193.1.1.17 255.255.255.248
R2(config)#
no shut
R3(config)#
int g0/0/0
R3(config)#
ip addr 193.1.1.18 255.255.255.248
R3(config)#
no shut
the segment between R1 and the server
network 193.1.1.0/29
block of 8
hosts .1, .2
the segment between R1 and R2
network 193.1.1.8/29
block of 8
hosts .9 , .10
the segment between the R2 and R3
network 193.1.1.16/29
block of 8
hosts .17 , .18
THIS IS INCORRECT!!!!
I have misunderstood the instructions.
the problem with this topology is that packets cannot pass through the routers. We dont have any ROUTING setup. ROUTING is covered in the next chapter.
For these labs, we dont need routing, but we need multiple routers to demo telnet and CDP. Here are the instructions:
my mistake was not putting all router interfaces in the same subnet. I tried to do this initially, but it wouldnt work because I had the routers linked together rather than connected by a switch.
The instructions say:
"Your PC and the router(s) are connected together with a switch"
this is the part I missed. The pc and all router interfaces should be on the same switch and the same network
Here is the corrected topology
Server Configuration
ipv4 address: 193.1.1.4
subnet mask: 255.255.255.248
default gateway: 193.1.1.1
Switch Configuration
SW1#
interface range f0/1-4
SW1(config-if-range)#
no shut
Router Configurations
R1(config)#
int g0/0/0
R1(config)#
ip addr 193.1.1.1 255.255.255.248
R1(config)#
no shut
the server's default gateway
R2(config)#
int g0/0/0
R2(config)#
ip addr 193.1.1.2 255.255.255.248
R2(config)#
no shut
R3(config)#
int g0/0/0
R3(config)#
ip addr 193.1.1.3 255.255.255.248
R3(config)#
no shut
Chapter 7 Hands-on Lab 7.1 Backing up your router IOS
1. verify connection to the server
R1#
ping 193.1.1.1
Type escape sequence to abort.
Sending 5, 100-byte ICMP Echos to 193.1.1.2, timeout is 2 seconds:
.!!!!
Success rate is 80 percent (4/5), round-trip min/avg/max = 0/1/5 ms
2. show contents of flash memory
R1#
show flash
System flash directory:
File Length Name/status
3 486899872isr4300-universalk9.16.06.04.SPA.bin
2 28282 sigdef-category.xml
1 227537 sigdef-default.xml
[487155691 bytes used, 2761893909 available, 3249049600 total]
3.17338e+06K bytes of processor board System flash (Read/Write)
show flash gives ALL of the files in flash memory
show version gives the current running file
3. show the IOS currently running
R1#
show version
Cisco IOS XE Software, Version 03.16.05.S - Extended Support Release
[cut]
ROM: IOS-XE ROMMON
Router uptime is 9 minutes, 39 seconds
Uptime for this control processor is 9 minutes, 39 seconds
System returned to ROM by power-on
System image file is "bootflash:/isr4300-universalk9.03.16.05.S.155-3.S5-ext.SPA.bin"
Last reload reason: PowerOn
[cut]
note that the file that is currently running is NOT located in the flash storage!!!
4. backup IOS from router to server
R1#
copy flash tftp
Source filename []?isr4300-universalk9.16.06.04.SPA.bin
Address or name of remote host []? 193.1.1.4
Destination filename [isr4300-universalk9.16.06.04.SPA.bin]? ENTER
Writing isr4300-universalk9.16.06.04.SPA.bin...!!!!!!!!!!!!!!!
[OK - 486899872 bytes]
486899872 bytes copied in 12.526 secs (125224 bytes/sec)
Chapter 7 Hands-on Lab 7.2 Upgrading or restoring your router IOS
1. verify connection to the server
R1#
ping 193.1.1.4
Type escape sequence to abort.
Sending 5, 100-byte ICMP Echos to 193.1.1.2, timeout is 2 seconds:
!!!!!
Success rate is 100 percent (5/5), round-trip min/avg/max = 0/0/1 ms
2. copy from tftp sever to flash
R1#
copy tftp flash TFTP comes first in the command since we are pulling from TFTP server.
In this command, remot host address is required before file name
Address or name of remote host []? 193.1.1.4
Source filename []?isr4300-universalk9.16.06.04.SPA.bin
Destination filename [isr4300-universalk9.16.06.04.SPA.bin]? ENTER
%Warning:There is a file already existing with this name
Do you want to over write? [confirm]
Accessing tftp://193.1.1.4/isr4300-universalk9.16.06.04.SPA-12-23-22...
Loading isr4300-universalk9.16.06.04.SPA-12-23-22.bin from 193.1.1.4: !!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!
[OK - 486899872 bytes]
486899872 bytes copied in 12.785 secs (122688 bytes/sec)
Chapter 7 Hands-on Lab 7.3 Backing up the router configuration
1. verify connection to the server
R1#
ping 193.1.1.2
Type escape sequence to abort.
Sending 5, 100-byte ICMP Echos to 193.1.1.4, timeout is 2 seconds:
!!!!!
Success rate is 100 percent (5/5), round-trip min/avg/max = 0/0/1 ms
2. copy running-confing to server
R1#
copy run tftp
Address or name of remote host []? 193.1.1.4
Destination filename [R1-confg]?ENTER "R1-confg" is the default name
Writing running-config...!!
[OK - 668 bytes]
668 bytes copied in 0.004 secs (167000 bytes/sec)
Chapter 7 Hands-on Lab 7.4 Using the Cisco Discovery Protocol (CDP)
R1#
show cdp
Global CDP information:
Sending CDP packets every 60 seconds
Sending a holdtime value of 180 seconds
Sending CDPv2 advertisements is enabled
R1#
show cdp interface
Vlan1 is administratively down, line protocol is down
Sending CDP packets every 60 seconds
Holdtime is 180 seconds
GigabitEthernet0/0/0 is up, line protocol is up
Sending CDP packets every 60 seconds
Holdtime is 180 seconds
GigabitEthernet0/0/1 is administratively down, line protocol is down
Sending CDP packets every 60 seconds
Holdtime is 180 seconds
GigabitEthernet0/0/2 is administratively down, line protocol is down
Sending CDP packets every 60 seconds
Holdtime is 180 seconds
R1#
show cdp entry *
Device ID: SW1
Entry address(es):
Platform: cisco 2960, Capabilities: Switch
Interface: GigabitEthernet0/0/0, Port ID (outgoing port): FastEthernet0/1
NOTE g0/0/0 is the outgoing port on this router, F0/1 is the port on the switch at other end
Holdtime: 157
Version :
Cisco IOS Software, C2960 Software (C2960-LANBASEK9-M), Version 15.0(2)SE4, RELEASE SOFTWARE (fc1)
Technical Support: http://www.cisco.com/techsupport
Copyright (c) 1986-2013 by Cisco Systems, Inc.
Compiled Wed 26-Jun-13 02:49 by mnguyen
advertisement version: 2
Duplex: full
R1#
show cdp entry neighbors
[no output]
R1#
show cdp neighbors detail
Device ID: SW1
Entry address(es):
Platform: cisco 2960, Capabilities: Switch
Interface: GigabitEthernet0/0/0, Port ID (outgoing port): FastEthernet0/1
Holdtime: 178
Version :
Cisco IOS Software, C2960 Software (C2960-LANBASEK9-M), Version 15.0(2)SE4, RELEASE SOFTWARE (fc1)
Technical Support: http://www.cisco.com/techsupport
Copyright (c) 1986-2013 by Cisco Systems, Inc.
Compiled Wed 26-Jun-13 02:49 by mnguyen
advertisement version: 2
Duplex: full
Chapter 7 Hands-on Lab 7.5 Using Telnet
enable telnet on R2 and set password
R2(config)#
line vty 0 15
R2(config-line)#
password telnet
R2(config-line)#
login
enable telnet on R3 and set password
R3(config)#
line vty 0 15
R3(config-line)#
password telnet
R3(config-line)#
login
note that the result of this command on each router, by default,
is to present all 15 lines in TWO SEPERATE chunks: 0-4 and 5-15
R3#
show run
[cut]
!
!
!
line con 0
!
line aux 0
!
line vty 0 4
password telnet
login
line vty 5 15
password telnet
login
!
!
!
end
--------------------------------------------------------------------------------
connect to R2 from R1
R1#
telnet 193.1.1.2
Trying 193.1.1..2 ...Open
User Access Verification
Password: telnet
prompt changes to R2 to indicate we are remoted in
R2>
exit the session
ctrl + shift + 6, x
prompt changes back to R1
R1#
--------------------------------------------------------------------------------
connect to R3 from R1
R1#
193.1.1.3 note that the word 'telnet' is not required bc we are still in telnet mode
Trying 193.1.1..3 ...Open
User Access Verification
Password: telnet
prompt changes to R3 to indicate we are remoted in
R3>
exit the session
ctrl + shift + 6, x
prompt changes back to R1
R1#
--------------------------------------------------------------------------------
We have exited the sessions, but they are still open
R1#
show sessions
Conn Host Address Byte Idle Conn Name
1 193.1.1.2 193.1.1.2 0 0 193.1.1.2
* 2 193.1.1.3 193.1.1.3 0 0 193.1.1.3
two telnet sessions- notice that the 'conn number' doesnt correspond to ip address in any way.
R1#
show users
Line User Host(s) Idle Location
* 0 con 0 193.1.1.2 00:00:03
193.1.1.3 00:00:43
this is saying one user is on this router, with two outbound connections (but it isnt showing that they are vty connections)
... they must both be considered 'console' connections outbound and are not considered 'vty' until they are received inbound
the asterisk means something different here than above... doesnt mean default(most recent)session... what does it mean?
back to R2
R2#
show users
Line User Host(s) Idle Location
* 4 vty 0 idle 00:00:00 193.1.1.1
Interface User Mode Idle Peer Address
this is saying that there is one (unnamed) user remoted in via line vty 4
back to R3
R3#
show users
Line User Host(s) Idle Location
* 4 vty 0 idle 00:00:00 193.1.1.1
Interface User Mode Idle Peer Address
this is saying that there is one (unnamed) user remoted in via line vty 4
-------------------------------------------------------------------------------------
Important Considerations:
-
asterisk indicates default session
-
when telnetting in, you will be in user mode. If there is no password already set for PRIVILEGED MODE, you will be unable to enter
-
be careful with 'exit'. it will exit the telnet session if you exit at priv. mode. Use 'disable' to leave priv mode.
-
after 'suspending' a session with ctrl+shift+6,x and youre back at your original priv. prompt, do not press enter to create line breaks-
rather than break lines as usual, the keystroke will cause this:
[Resuming connection 1 to 193.1.1.2 ... ]
prompt will sit here until you strike enter again, then you'll return to that session. What is actually happening is that
youre connecting to the 'default' telnet connection. The same behavior happens when youre at the 'show sessions' screen.
Even if you are not viewing active sessions, the enter key(twice) will connect you to the default session
-
you can use disconnect or exit to end a session
-
Ex: disconnect 1 at the show sessions screen
Chapter 7 Hands-on Lab 7.6 Resolving Hostnames
We're going to build a host table on R1 so we can connect to the other routers via hostname rather than type in the IP address
the command is ip host name arg ip arg
R1(config)#
ip host R2 193.1.1.2
R1(config)#
ip host R3 193.1.1.3
Now if we enter R2 or telnet R2 we get the telnet prompt
R1# R2
Trying 193.1.1.2 ...Open
User Access Verification
Password:
same for the PING command
R1# ping R2
Type escape sequence to abort.
Sending 5, 100-byte ICMP Echos to 193.1.1.2, timeout is 2 seconds:
!!!!!
Success rate is 100 percent (5/5), round-trip min/avg/max = 0/0/2 ms
R1#
show hosts
Default Domain is not set
Name/address lookup uses domain service
Name servers are 255.255.255.255
Codes: UN - unknown, EX - expired, OK - OK, ?? - revalidate
temp - temporary, perm - permanent
NA - Not Applicable None - Not defined
Host Port Flags Age Type Address(es)
R2 None (perm, OK) 0 IP 193.1.1.2
R3 None (perm, OK) 0 IP 193.1.1.3
R1#
telnet R2
R2>
CTRL + SHIFT + 6, X
R1#
telnet R3
R3>
CTRL + SHIFT + 6, X
R1#
show session
Conn Host Address Byte Idle Conn Name
1 R2 193.1.1.2 0 0 R2
* 2 R3 193.1.1.3 0 0 R3
Chapter 7 Review Questions
1. What does the command
confreg 0x2142
provide?
bypass startup-config, to allow password reset
2. Which command will copy the IOS to a backup host on your network?
copy flash tftp
3. You are troubleshooting a connectivity problem in your corporate network and want to isolate the problem. You suspect that a router on the route to an unreachable
network is at fault. What IOS user exec command should you issue?
traceroute
note this is not a priviliged mode command; it can be run from user mode
4. You copy a configuration from a network host to a router's RAM. The configuration looks correct, yet it is no working at all. What could the problem be?
when you perform a copy from a network host to a router, the interfaces are automatically shut down and have to be manually enabled with no shutdown
5. A network administrator wants to upgrade the IOS of a router without removing the image currently installed. What command will display the amount of memory consumed by the
current IOS image and indicate whether there is enough room available to hold both the current and new images?
show flash
6. The corporate office sends you a new router to connect, but upon connecting the console cable, you see that there is already a configuration on the router.
What should be done before a new configuration is entered in the router?
erase NVRAM and restart the router
erase startup-config
reload
7. Which command loads a new version of the Cisco IOS into a router?
copy tftp flash
8. Which command will show you the IOS version running on your router?
show version
9. What should the configuration register value be after you successfully complete the password recovery procedure and return the router to normal operation?
0x2102
10. You save the configuration on a router with the
copy running-config startup-config
command and reboot the router. The router, however, comes up with a blank configuration. What can the problem be?
wrong config register causing you to bypass startup-confing in NVRAM
11. If you want to have more than one Telnet session open at the same time, what keystroke combination would you use?
CTRL+SHIFT+6, X
12. You are unsuccessful in telnetting into a remote device, but you could telnet to the router earlier, However, you can still ping the remote device.
What can the problem be?
access control list could be filtering telnet
OR
the VTY password may not be set on the target
13. What information is displayed by the
show hosts
command?
gives info on temporary DNS entries and permanent name-to-address mappings created using the ip host command
14. Name three commands that can be used to check LAN connectivity problems on a router?
trace
show interfaces
show ip route
15. You telnet to a router and make your necessary changes; now you want to end the Telnet session. What command do you type in?
exit
16. You telnet into a remote device and type
debug ip rip
but no output from the
debug
command is seen. What could the problem be?
to see console messages through a telnet session, you must enter the command terminal monitor
17. Which command displays the configuration register setting?
show version
18. You need to gather the IP address of a remote switch that is located in Hawaii. What can you do to find the address?
show cdp neighbors detail
19. You have your laptop directly connected into a router's Ethernet port. Which are requirements for the
copy flash tftp
command to be successful?
have a TFTP server running on the laptop
laptop must have an IP on the same subnet as the router interface
give the IP address of the laptop when asked after entering the command
20. The configuration register setting of 0x2102 provides what function to a router?
points to NVRAM for startup-configuration AND boot sequence
END CHAPTER 7
26 hours 1-19 thru 1-26-22
original total hours 89
7 hours review 12-23-22
review total hours 20.5
book page 344/822
avg 15 min/page (reading and exercises/labs)
Chapter 8 Exercises
pg 374
before I begin to configure this network, I want to look closer at the HARDWARE
Todd mentions these routers:
2811 with four serial interfaces and switch module or wireless card
1841
while the book was published in 2011, both routers appear to be available in 2021 packet tracer,
but both are considered legacy as of Feb 2022.
The 2811:
The 1841:
we're going to need to understand the MODULES. What are these?
a few examples:
NM-1E is a 1-port ethernet module
NM-1FE-TX is a fast ethernet module
NM-8A/s is an Eight Port Async/Sync Network Module
HWIC-2T is a 2-port serial WAN interface card
HWIC-AP-AG-B is a wireless card
What is an "NM module"?
A network module is a software module that implements a specific
function in a network stack, such as a data link interface, a transport protocol,
or a network application.
What is a "HWIC module"?
A high-speed WAN interface card
Here is a look inside a real 2811:
Back to the requirements for our lab- Todd says the 2811 'Corp' router needs a switch module
and four serial interfaces. NOTE the book doesnt give specifics on how to create the topology in Packet Tracer.
Our Packet Tracer 2811 offers these modules:
The NM-ESW-16 appears to be the only 'switch module', so I will add that.
And the HWIC-2T is a 2-Port Serial High-Speed WAN Interface Card, providing 2 serial ports.
I will add two of these.
next: R3, which needs to be a 2811 with a wirless card. I will add the HWIC-AP-AG-B:
The HWIC-AP-AG-B module is a High-Speed WAN Interface Card providing integrated Access Point
functionality in the Cisco 1800 (Modular), Cisco 2800,
and Cisco 3800 Integrated Services Routers.
It supports Single Band 802.11b/g or Dual Band 802.11a/b/g radios.
our router hardware is in place:
and here is where we need to end up
Next we need to figure out how to connect the server farm to the switch card on R1:
if I use the auto-select cable, I get a copper crossover cable connecting at fa0/0 on the router.
Per the diagram fa0/0 should
connect to R3. I need to connect the servers to the switch card on R1.
Instead of using the auto-select cable, I'll try a straight-through cable.
Success. While the auto-select cable did not give me an option as to what port it will connect to, I did get the option when
manually applying the straight-through cable. Instead of connecting to F0/0 which would require a crossover-cable(computer to router),
I will connect to the integrated switch at port F1/0, then connect the other two servers to F1/1 and F1/2, respectively.
Also worth noting: the Physical Device diagrams in Packet Tracer do not show cables plugged into the ports.
We are relying on the labels on the logical diagram to see which cables are plugged into which ports...
As far as how we can tell what is connected from within the CLI.. I dont know right now.
Now I will connect the other routers. Here is the chart specifiying what interfaces should be used:
Router
Network Address
Interface
Address
CORP
10.1.1.0
Vlan1 (switch card)
10.1.1.1
10.1.2.0
S0/0/0
10.1.2.1
10.1.3.0
S0/0/1 (DCE)
10.1.3.1
10.1.4.0
S0/1/0
10.1.4.1
10.1.5.0
F0/0
10.1.5.1
R1
10.1.2.0
S0/0/0 (DCE)
10.1.2.2
10.1.3.0
S0/0/1
10.1.3.2
192.168.10.0
F0/0
192.168.10.1
192.168.20.0
F0/1
192.168.20.1
R2
10.1.4.0
S0/0/0 (DCE)
10.1.4.2
192.168.30.0
F0/0
192.168.30.1
192.168.40.0
F0/0
192.168.40.1
R3
10.1.5.0
F0/0
10.1.5.2
172.16.10.0
Dot11Radio0/0/0
172.16.10.1
PROBLEM
The R1 router doesnt appear to have any serial interfaces
I will add an HWIC-2T card to both R1 and R2 since the diagram calls for serial interfaces.
The HWIC-2T is a Cisco 2-Port Serial High-Speed WAN Interface Card, providing 2 serial ports.
PROBLEM
The Corp router is not showing the expected available interfaces. I need to connect R1 to the S0/0/0 interface on Corp and R2 to the S0/0/1 interface on Corp.
My Corp router is not showing those interfaces:
Solution
the placement of the cards on the router determines which interface numbers will be available.
In this case, it seems the interfaces start from the bottom right corner and increase on each slot moving clockwise. I found this out by filling all four slots on my router
which led to all interfaces being available. I then ran a card in each slot individually to isolate which interface numbers correspond to each slot:
Interestingly, while the physical slots seem to follow a 'clockwise' pattern, the list of available slots in the logical diagram does not;
We get an output of interfaces corresponding to slot 2, then 3, 1, and 4. This is a 'bottom to top' then 'left to right' pattern. Tricky.
Having said all that... I will run cards in slots 1 and 2 for this lab since we only need interfaces S0/0/0, S0/0/1, S0/1/0
The Router topology:
I'm not clear on the connections from R1 and R2 to the clients.. I assume there are switches involved.
For now I will follow the next steps in the book which
are to configure the corp router as follows:
Router(config)#
hostname Corp
Corp(config)#
enable secret todd
Corp(config)#
interface vlan 1
Corp(config-if)#
description Switch Card to Core Network
Corp(config-if)#
ip address 10.1.1.1 255.255.255.0
Corp(config-if)#
no shut
----------------------------------------------------------------------------------------------------------------
Corp(config-if)#
int f1/0
Corp(config-if)#
description Switch Port connection to WWW Server
Corp(config-if)#
no shutdown
Corp(config-if)#
int f1/1
Corp(config-if)#
description Switch Port connection to Email Server
Corp(config-if)#
no shutdown
Corp(config-if)#
int f1/2
Corp(config-if)#
description Switch Port connection to DNS Server
Corp(config-if)#
no shutdown
----------------------------------------------------------------------------------------------------------------
Corp(config-if)#
int s0/0/0
Corp(config-if)#
description 1st Connection to R1
Corp(config-if)#
ip address 10.1.2.1 255.255.255.0
Corp(config-if)#
no shut
Corp(config-if)#
int s0/0/1
Corp(config-if)#
description 2nd Connection to R1
Corp(config-if)#
ip address 10.1.3.1 255.255.255.0
Corp(config-if)#
no shut
Corp(config-if)#
int s0/1/0
Corp(config-if)#
description Connection to R2
Corp(config-if)#
ip address 10.1.4.1 255.255.255.0
Corp(config-if)#
no shut
Corp(config-if)#
int fa0/0
Corp(config-if)#
description Connection to R3
Corp(config-if)#
ip address 10.1.5.1 255.255.255.0
Corp(config-if)#
no shut
----------------------------------------------------------------------------------------------------------------
Corp(config-if)#
line con 0
Corp(config-if)#
password console
Corp(config-if)#
login
Corp(config-if)#
logging synchro
Corp(config-if)#
exec-timeout 0 0
----------------------------------------------------------------------------------------------------------------
Corp(config-if)#
line aux 0
Corp(config-if)#
password aux
Corp(config-if)#
login
Corp(config-if)#
exit
----------------------------------------------------------------------------------------------------------------
Corp(config)#
line vty ?
<1-15>Last Line number
Corp(config)#
line vty 0 15
Corp(config-if)#
password telnet
Corp(config-if)#
login
Corp(config-if)#
exit
----------------------------------------------------------------------------------------------------------------
Corp(config)#
no ip domain lookup
Corp(config)#
banner motd # This is my Corp 2811 ISR Router #
Ctrl + Z
%SYS-5-CONFIG_I: Configured from console by console
(Ctrl-Z: When in a config mode, ends the config mode and returns you to privileged EXEC mode.... same as typing exit(?))
Corp#
copy run start
Destination filename [startup-config]?
Building configuration...
[OK]
----------------------------------------------------------------------------------------------------------------
Corp#
show ip int br
Interface IP-Address OK? Method Status Protocol
FastEthernet0/0 10.1.5.1 YES manual up down
FastEthernet0/1 unassigned YES unset administratively down down
Serial0/0/0 10.1.2.1 YES manual down down
Serial0/0/1 10.1.3.1 YES manual down down
Serial0/1/0 10.1.4.1 YES manual down down
Serial0/1/1 unassigned YES unset administratively down down
FastEthernet1/0 unassigned YES unset up up
FastEthernet1/1 unassigned YES unset up up
FastEthernet1/2 unassigned YES unset up up
FastEthernet1/3 unassigned YES unset administratively down down
FastEthernet1/4 unassigned YES unset administratively down down
FastEthernet1/5 unassigned YES unset administratively down down
FastEthernet1/6 unassigned YES unset administratively down down
FastEthernet1/7 unassigned YES unset administratively down down
FastEthernet1/8 unassigned YES unset administratively down down
FastEthernet1/9 unassigned YES unset administratively down down
FastEthernet1/10 unassigned YES unset administratively down down
FastEthernet1/11 unassigned YES unset administratively down down
FastEthernet1/12 unassigned YES unset administratively down down
FastEthernet1/13 unassigned YES unset administratively down down
FastEthernet1/14 unassigned YES unset administratively down down
FastEthernet1/15 unassigned YES unset administratively down down
Vlan1 10.1.1.1 YES manual up up
----------------------------------------------------------------------------------------------------------------
Corp#
show run
Building configuration...
Current configuration : 2073 bytes
!
version 15.1
no service timestamps log datetime msec
no service timestamps debug datetime msec
no service password-encryption
!
hostname Corp
!
!
!
enable secret 5 $1$mERr$V5ujdIM9bTB/I.ipB0gkJ0
!
!
!
!
!
!
no ip cef
no ipv6 cef
!
!
!
!
license udi pid CISCO2811/K9 sn FTX1017U440-
!
!
!
!
!
!
!
!
!
no ip domain-lookup
!
!
spanning-tree mode pvst
!
!
!
!
!
!
interface FastEthernet0/0
description connection to R3
ip address 10.1.5.1 255.255.255.0
duplex auto
speed auto
!
interface FastEthernet0/1
no ip address
duplex auto
speed auto
shutdown
!
interface Serial0/0/0
description 1st connection to R1
ip address 10.1.2.1 255.255.255.0
clock rate 2000000
!
interface Serial0/0/1
description 2nd connection to R1
ip address 10.1.3.1 255.255.255.0
clock rate 2000000
!
interface Serial0/1/0
description connection to R2
ip address 10.1.4.1 255.255.255.0
!
interface Serial0/1/1
no ip address
clock rate 2000000
shutdown
!
interface FastEthernet1/0
description switch port connection to WWW Server
!
interface FastEthernet1/1
description switch port connection to Email Server
!
interface FastEthernet1/2
description switch port connection to DNS Server
!
interface FastEthernet1/3
shutdown
!
interface FastEthernet1/4
shutdown
!
interface FastEthernet1/5
shutdown
!
interface FastEthernet1/6
shutdown
!
interface FastEthernet1/7
shutdown
!
interface FastEthernet1/8
shutdown
!
interface FastEthernet1/9
shutdown
!
interface FastEthernet1/10
shutdown
!
interface FastEthernet1/11
shutdown
!
interface FastEthernet1/12
shutdown
!
interface FastEthernet1/13
shutdown
!
interface FastEthernet1/14
shutdown
!
interface FastEthernet1/15
shutdown
!
interface Vlan1
description Switch Card to Core Network
ip address 10.1.1.1 255.255.255.0
!
ip classless
!
ip flow-export version 9
!
!
!
banner motd ^C This is my Corp 2811 ISR Router ^C
!
!
!
!
!
line con 0
exec-timeout 0 0
password console
logging synchronous
login
!
line aux 0
password aux
login
!
line vty 0 4
password telnet
login
line vty 5 15
password telnet
login
!
!
!
end
-----------------------------------------------------------------------------------------------------------------------
more configurations:
R1
Router(config)#
hostname R1
R1(config)#
enable secret todd
R1(config)#
int s0/0/0
R1(config-if)#
ip address 10.1.2.2 255.255.255.0
R1(config-if)#
Decription 1st connection to corp router
R1(config-if)#
no shut
-----------------------------------------------------------------------------------------------
R1(config-if)#
int s0/0/1
R1(config-if)#
ip address 10.1.3.2 255.255.255.0
R1(config-if)#
Decription 2nd connection to corp router
R1(config-if)#
no shut
-----------------------------------------------------------------------------------------------
R1(config-if)#
int f0/0
R1(config-if)#
ip address 192.168.10.1 255.255.255.0
R1(config-if)#
Decription connection to finance
R1(config-if)#
no shut
-----------------------------------------------------------------------------------------------
R1(config-if)#
int f0/1
R1(config-if)#
ip address 192.168.20.1 255.255.255.0
R1(config-if)#
Decription connection to marketing
R1(config-if)#
no shut
R1(config-if)#
exit
-----------------------------------------------------------------------------------------------
R1(config)#
line con 0
R1(config-line)#
password console
R1(config-line)#
login
R1(config-line)#
logging synchronous
R1(config-line)#
exec-timeout 0 0
-----------------------------------------------------------------------------------------------
R1(config-line)#
line aux 0
R1(config-line)#
password aux
R1(config-line)#
login
R1(config-line)#
exit
-----------------------------------------------------------------------------------------------
R1(config)#
line vty 0 ?
<0-15> Last Line number
R1(config)#
line vty 0 807
R1(config-line)#
password telnet
R1(config-line)#
login
R1(config-line)#
banner motd # This is my R1 Router #
R1(config-line)#
exit
-----------------------------------------------------------------------------------------------
R1(config)#
no ip domain-lookup
R1(config)#
exit
R1#
copy run start
R2
Router(config)#
hostname R2
R2(config)#
enable secret todd
R2(config)#
int s0/0/0
R2(config-if)#
ip address 10.1.4.2 255.255.255.0
R2(config-if)#
description connection to corp router
R2(config-if)#
no shut
-----------------------------------------------------------------------------------------------
R2(config-if)#
int f0/0
R2(config-if)#
ip address 192.168.30.1 255.255.255.0
R2(config-if)#
description connection to sales PC
R2(config-if)#
no shut
-----------------------------------------------------------------------------------------------
R2(config-if)#
int f0/1
R2(config-if)#
ip address 192.168.40.1 255.255.255.0
R2(config-if)#
description connection to HR pc
R2(config-if)#
no shut
-----------------------------------------------------------------------------------------------
R2(config-if)#
line con 0
R2(config-line)#
password console
R2(config-line)#
login
R2(config-line)#
logging synchronous
R2(config-line)#
exec-timeout 0 0
-----------------------------------------------------------------------------------------------
R2(config-line)#
line aux 0
R2(config-line)#
password aux
R2(config-line)#
login
R2(config-line)#
exit
-----------------------------------------------------------------------------------------------
R2(config)#
line vty 0 ?
<0-15> Last Line number
R2(config)#
line vty 0 807
R2(config-line)#
password telnet
R2(config-line)#
login
R2(config-line)#
banner motd # This is my R1 Router #
R2(config-line)#
exit
-----------------------------------------------------------------------------------------------
R2(config)#
no ip domain-lookup
R2(config)#
exit
R2#
copy run start
R3
Router(config)#
hostname R3
R3(config)#
enable secret todd
R3(config)#
int f0/0
R3(config-if)#
ip address 10.1.5.2 255.255.255.0
R3(config-if)#
description connection to corp router
R3(config-if)#
no shut
-----------------------------------------------------------------------------------------------
R3(config-if)#
int dot11radio0/0/0
R3(config-if)#
ip address 172.16.10.1 255.255.255.0
R3(config-if)#
description WLAN for mobile user
R3(config-if)#
no shut
R3(config-if)#
ssid ADMIN
stuck here 2-5-22-- packet tracer isnt taking me into the config-if-ssid prompt
R3(config-if-ssid)#
guest-mode
R3(config-if-ssid)#
authentication open
R3(config-if-ssid)#
ingrastructure-ssid
R3(config-if-ssid)#
exit
-----------------------------------------------------------------------------------------------
R3(config-if)#
line con 0
R3(config-line)#
password console
R3(config-line)#
login
R3(config-line)#
logging synchronous
R3(config-line)#
exec-timeout 0 0
-----------------------------------------------------------------------------------------------
R3(config-line)#
line aux 0
R3(config-line)#
password aux
R3(config-line)#
login
R3(config-line)#
exit
-----------------------------------------------------------------------------------------------
R3(config)#
line vty 0 ?
<0-15> Last Line number
R3(config)#
line vty 0 807
R3(config-line)#
password telnet
R3(config-line)#
login
R3(config-line)#
banner motd # This is my R1 Router #
R3(config-line)#
exit
-----------------------------------------------------------------------------------------------
R3(config)#
no ip domain-lookup
R3(config)#
exit
R3#
copy run start
PROBLEM
i cant get into conf-if-ssid prompt
R3(config-if)#
ssid ADMIN
%LINK-5-CHANGED: Interface Dot11Radio0/0/0, changed state to administratively down
%LINEPROTO-5-UPDOWN: Line protocol on Interface Dot11Radio0/0/0, changed state to down
%LINK-5-CHANGED: Interface Dot11Radio0/0/0, changed state to up
%LINEPROTO-5-UPDOWN: Line protocol on Interface Dot11Radio0/0/0, changed state to up
R3(config-if)#
research led me to this thread, which is a dead end:
further research led me here:
R3(config)# global config mode
R3(config)#
dot11 ssid ADMIN
creates an SSID or lets you config an existing SSID
R3(config-ssid)#
guest-mode
R3(config-ssid)#
%LINK-5-CHANGED: Interface Dot11Radio0/0/0, changed state to administratively down
%LINEPROTO-5-UPDOWN: Line protocol on Interface Dot11Radio0/0/0, changed state to down
%LINK-5-CHANGED: Interface Dot11Radio0/0/0, changed state to up
%LINEPROTO-5-UPDOWN: Line protocol on Interface Dot11Radio0/0/0, changed state to up
R3(config-ssid)#
authentication open
R3(config-ssid)#
%LINK-5-CHANGED: Interface Dot11Radio0/0/0, changed state to administratively down
%LINEPROTO-5-UPDOWN: Line protocol on Interface Dot11Radio0/0/0, changed state to down
%LINK-5-CHANGED: Interface Dot11Radio0/0/0, changed state to up
%LINEPROTO-5-UPDOWN: Line protocol on Interface Dot11Radio0/0/0, changed state to up
R3(config-ssid)#
infrastructure-ssid
R3(config-ssid)#infrastructure-ssid
^
% Invalid input detected at '^' marker.
this command given by the book doesnt appear to be valid
R3(config-ssid)#
?
authentication authentication method
exit Exit from ssid sub mode
guest-mode guest ssid
no Negate a command or set it's defaults
wpa-psk Configure Wi-Fi Protected Access pre-shared key
back into the interface to see what the options are
R3(config-ssid)#
int dot110/0/0
R3(config-if)#
?
arp Set arp type (arpa, probe, snap) or timeout or log options
bandwidth Set bandwidth informational parameter
cdp CDP interface subcommands
crypto Encryption/Decryption commands
delay Specify interface throughput delay
description Interface specific description
encryption Configure dot11 encryption parameters
exit Exit from interface configuration mode
fair-queue Enable Fair Queuing on an Interface
hold-queue Set hold queue depth
ip Interface Internet Protocol config commands
mac-address Manually set interface MAC address
mtu Set the interface Maximum Transmission Unit (MTU)
no Negate a command or set its defaults
priority-group Assign a priority group to an interface
service-policy Configure QoS Service Policy
shutdown Shutdown the selected interface
speed Set allowed radio bit rates
ssid Configure radio service set parameters
tx-ring-limit Configure PA level transmit ring limit
i'll consider the problem *mostly* solved. I was able to assign the SSD.
The infrastructure command may be expendable in this case... to be determined
here is our configuration for R3
R3#
show run
Building configuration...
Current configuration : 1682 bytes
!
version 15.1
no service timestamps log datetime msec
no service timestamps debug datetime msec
no service password-encryption
!
hostname R3
!
!
!
enable secret 5 $1$mERr$V5ujdIM9bTB/I.ipB0gkJ0
!
!
ip dhcp excluded-address 172.16.10.1 172.16.10.10
!
ip dhcp pool Admin
network 172.16.10.0 255.255.255.0
default-router 172.16.10.1
!
dot11 ssid ADMIN
authentication open
guest-mode
!
dot11 ssid ADMIN2
authentication open
guest-mode
!
!
!
ip cef
no ipv6 cef
!
!
!
!
license udi pid CISCO2811/K9 sn FTX1017RE40-
!
!
!
!
!
!
!
!
!
no ip domain-lookup
ip name-server 172.16.10.4
!
!
spanning-tree mode pvst
!
!
!
!
!
!
interface FastEthernet0/0
description connection to corp router
ip address 10.1.5.2 255.255.255.0
duplex auto
speed auto
!
interface FastEthernet0/1
no ip address
duplex auto
speed auto
shutdown
!
interface Dot11Radio0/0/0
description WAN for mobile
ip address 172.16.10.1 255.255.255.0
speed 12.0 18.0 24.0 36.0 48.0 54.0 6.0 9.0 basic-1.0 basic-11.0 basic-2.0 basic-5.5
ssid ADMIN2
!
interface Dot11Radio0/0/1
no ip address
speed 18.0 36.0 48.0 54.0 9.0 basic-12.0 basic-24.0 basic-6.0
!
interface Serial0/1/0
no ip address
clock rate 2000000
!
interface Serial0/1/1
no ip address
clock rate 2000000
!
interface Vlan1
no ip address
shutdown
!
router rip
version 2
network 10.0.0.0
network 172.16.0.0
!
ip classless
ip route 0.0.0.0 0.0.0.0 10.1.5.1
!
ip flow-export version 9
!
!
!
banner motd ^C this is R3 $
this is R3 ^C
!
!
!
!
!
line con 0
exec-timeout 0 0
password console
logging synchronous
login
!
line aux 0
password aux
login
!
line vty 0 4
password telnet
login
line vty 5 15
password telnet
login
!
!
!
end
to summarize...
the book is a little off here.
-----------------------------------------------------------------------------------------------
R3(config-if)#
int dot11radio0/0/0
R3(config-if)#
ip address 172.16.10.1 255.255.255.0
R3(config-if)#
description WLAN for mobile user
R3(config-if)#
no shut
at this point we have created a wireless interface with an IP address but no SSID exists on this router
interface Dot11Radio0/0/0
description test router 2
ip address 172.16.10.1 255.255.255.0
speed 12.0 18.0 24.0 36.0 48.0 54.0 6.0 9.0 basic-1.0 basic-11.0 basic-2.0 basic-5.5
Trying to use the command "ssid ADMIN" doesnt work here. The below commands are invalid here:
R3(config-if)#
ssid ADMIN
R3(config-if-ssid)#
guest-mode
R3(config-if-ssid)#
authentication open
R3(config-if-ssid)#
ingrastructure-ssid
R3(config-if-ssid)#
exit
-----------------------------------------------------------------------------------------------
We need to drop out of config-if, back to config, and enter SSID config mode
-----------------------------------------------------------------------------------------------
R3(config-if)#
exit
R3(config)#
dot11 ssid ADMIN2 creates an ssid named ADMIN2, and puts us into SSID config mode
R3(config-ssid)#
guest-mode
R3(config-ssid)#
authentication open
then out of config-ssid and back to interface config
R3(config-ssid)#
exit
R3(config)
int dot11r0/0/0
R3(config-if)
?
arp Set arp type (arpa, probe, snap) or timeout or log options
bandwidth Set bandwidth informational parameter
cdp CDP interface subcommands
crypto Encryption/Decryption commands
delay Specify interface throughput delay
description Interface specific description
encryption Configure dot11 encryption parameters
exit Exit from interface configuration mode
fair-queue Enable Fair Queuing on an Interface
hold-queue Set hold queue depth
ip Interface Internet Protocol config commands
mac-address Manually set interface MAC address
mtu Set the interface Maximum Transmission Unit (MTU)
no Negate a command or set its defaults
priority-group Assign a priority group to an interface
service-policy Configure QoS Service Policy
shutdown Shutdown the selected interface
speed Set allowed radio bit rates
ssid Configure radio service set parameters
tx-ring-limit Configure PA level transmit ring limit
we have the option for ssid
R3(config-if)
ssid ADMIN2
%LINK-5-CHANGED: Interface Dot11Radio0/0/0, changed state to administratively down
%LINEPROTO-5-UPDOWN: Line protocol on Interface Dot11Radio0/0/0, changed state to down
%LINK-5-CHANGED: Interface Dot11Radio0/0/0, changed state to up
%LINEPROTO-5-UPDOWN: Line protocol on Interface Dot11Radio0/0/0, changed state to up
the router resets the interface..
-----------------------------------------------------------------------------------------------
R3(config-if)
do show run
[cut]
!
!
dot11 ssid ADMIN2
authentication open
guest-mode
!
!
[cut]
!
interface Dot11Radio0/0/0
description test router 2
ip address 172.16.10.1 255.255.255.0
speed 12.0 18.0 24.0 36.0 48.0 54.0 6.0 9.0 basic-1.0 basic-11.0 basic-2.0 basic-5.5
ssid ADMIN2
!
[cut]
the SSID is created and assigned to the interface
To summarize.
Wrong: create the dot11 interface, then create the SSID from CONFIG-IF mode, which puts you into CONFIG-IF-SSID (there is no such mode on this router) mode, then modify the ssid from there...
Correct: create the dot11 interface. Exit CONFIG-IF and go back to GLOBAL CONFIG. Create the SSID which puts you in CONFIG-SSID mode.
Configure the ssid. Then exit CONFIG-SSID. Back into CONFIG-IF, assign the SSID
We have one more task for R3- Configuring the DHCP pool for wireless clients.
R3(config)#
ip dhcp pool Admin creating the pool name as "Admin"
R3(dhcp-config)#
network 172.16.10.0 255.255.255.0
R3(dhcp-config)#
default-router 172.16.10.1 aka default-gateway for clients in the pool
R3(dhcp-config)#
ip name-server 172.16.10.4 dns server
*automatically exits dhcp-config prompt*
R3(config)#
ip dhcp excluded-address 172.16.10.1 172.16.10.10 excludes the range given
172.16.10.1 is the router interface- we need to specifically exclude it from the pool
this setup should allow the wireless client to pick up an IP after connecting to the open SSID.
However, I was having trouble at first-
even though I seemed to have the SSID set correctly, i was hitting a WEP password prompt
i didnt see any obvious issues with the wifi module im using on the laptop:
The Linksys-WPC300N module provides one 2.4GHz wireless interface suitable for connection to wireless networks.
The module supports protocols that use Ethernet for LAN access.
I ended up creating a new SSID, with the same settings as the original:
R3(config)#
dot11 ssid ADMIN2
R3(config-ssid)#
guest-mode
R3(config-ssid)#
authentication open
and then I assigned the ip address to ssid ADMIN2 instead of the orginal ADMIN ssid
R3(config)#
int dot110/0/0
R3(config-if)#
ip address 172.16.10.1 255.255.255.0
R3(config-if)#
description WLAN for mobile user
R3(config-if)#
no shut
R3(config-if)#
ssid ADMIN2
R3#
show run
Building configuration...
Current configuration : 1467 bytes
!
version 15.1
no service timestamps log datetime msec
no service timestamps debug datetime msec
no service password-encryption
!
hostname R3
!
!
!
enable secret 5 $1$mERr$V5ujdIM9bTB/I.ipB0gkJ0
!
!
ip dhcp excluded-address 172.16.10.1 172.16.10.10
!
ip dhcp pool Admin
network 172.16.10.0 255.255.255.0
default-router 172.16.10.1
!
dot11 ssid ADMIN
authentication open
guest-mode
!
dot11 ssid ADMIN2
authentication open
guest-mode
!
!
!
ip cef
no ipv6 cef
!
!
!
!
license udi pid CISCO2811/K9 sn FTX1017RE40-
!
!
!
!
!
!
!
!
!
no ip domain-lookup
ip name-server 172.16.10.4
!
!
spanning-tree mode pvst
!
!
!
!
!
!
interface FastEthernet0/0
description connection to corp router
ip address 10.1.5.2 255.255.255.0
duplex auto
speed auto
!
interface FastEthernet0/1
no ip address
duplex auto
speed auto
shutdown
!
interface Dot11Radio0/0/0
description WAN for mobile
ip address 172.16.10.1 255.255.255.0
speed 12.0 18.0 24.0 36.0 48.0 54.0 6.0 9.0 basic-1.0 basic-11.0 basic-2.0 basic-5.5
ssid ADMIN2
!
interface Dot11Radio0/0/1
no ip address
speed 18.0 36.0 48.0 54.0 9.0 basic-12.0 basic-24.0 basic-6.0
!
interface Vlan1
no ip address
shutdown
!
ip classless
!
ip flow-export version 9
!
!
!
banner motd ^C this is R3 $
this is R3 ^C
!
!
!
!
!
line con 0
exec-timeout 0 0
password console
logging synchronous
login
!
line aux 0
password aux
login
!
line vty 0 4
password telnet
login
line vty 5 15
password telnet
login
!
!
!
end
Recall the DHCP configuration on R3:
R3(config)#
ip dhcp pool Admin creating the pool name as "Admin"
R3(dhcp-config)#
network 172.16.10.0 255.255.255.0
R3(dhcp-config)#
default-router 172.16.10.1 aka default-gateway for clients in the pool
R3(dhcp-config)#
ip name-server 172.16.10.4 dns server
*automatically exits dhcp-config prompt*
R3(config)#
ip dhcp excluded-address 172.16.10.1 172.16.10.10 excludes the range given
172.16.10.1 is the router interface- we need to specifically exclude it from the pool
we can check the configuration:
R3#
show ip dhcp pool
Pool Admin :
Utilization mark (high/low) : 100 / 0
Subnet size (first/next) : 0 / 0
Total addresses : 254
Leased addresses : 1
Excluded addresses : 1
Pending event : none
1 subnet is currently in the pool
Current index IP address range Leased/Excluded/Total
172.16.10.1 172.16.10.1 - 172.16.10.254 1 / 1 / 254
R3#
show ip dhcp binding
IP address Client-ID/ Lease expiration Type
Hardware address
172.16.10.11 00D0.979A.733B -- Automatic
the show command is becoming more familiar
R3#
show ip?
access-lists List access lists
arp IP ARP table
bgp BGP information
cache IP fast-switching route cache
cef Cisco Express Forwarding
dhcp Show items in the DHCP database
eigrp IP-EIGRP show commands
inspect CBAC (Context Based Access Control) information
interface IP interface status and configuration
ips IPS (Intrusion Prevention System) information
nat IP NAT information
nbar Network-Based Application Recognition
ospf OSPF information
protocols IP routing protocol process parameters and statistics
rip IP RIP show commands
route IP routing table
ssh Information on SSH
we'll use show ip route soon on all the routers. For now, here is the output for R3:
R3#
show ip route
Codes: L - local, C - connected, S - static, R - RIP, M - mobile, B - BGP
D - EIGRP, EX - EIGRP external, O - OSPF, IA - OSPF inter area
N1 - OSPF NSSA external type 1, N2 - OSPF NSSA external type 2
E1 - OSPF external type 1, E2 - OSPF external type 2, E - EGP
i - IS-IS, L1 - IS-IS level-1, L2 - IS-IS level-2, ia - IS-IS inter area
* - candidate default, U - per-user static route, o - ODR
P - periodic downloaded static route
Gateway of last resort is not set
10.0.0.0/8 is variably subnetted, 2 subnets, 2 masks
C 10.1.5.0/24 is directly connected, FastEthernet0/0
L 10.1.5.2/32 is directly connected, FastEthernet0/0
172.16.0.0/16 is variably subnetted, 2 subnets, 2 masks
C 172.16.10.0/24 is directly connected, Dot11Radio0/0/0
L 172.16.10.1/32 is directly connected, Dot11Radio0/0/0
Before moving on to the routing configurations, here is a review of the topology
I have switched over to the DrawIO diagram app to lay out the topology.
The Packet Tracer diagram becomes
too crowded to see the labels; it's labeling system forces awkward positioning of the objects; the interface
label's cant be moved, so if objects are too close together their labels cover eachother.. not good.
DrawIO allows a cleaner layout with plenty of room to label interfaces and ip addresses.
As a compromise, I'll use both.
I have the packet tracer objects spread out just enough to see the interfaces
and the label for each router. From here I can jump into the CLI for each device.
The DrawIO diagram allows me to cleary see IP addresses
I want to also review all of the configurations we just performed:
PROBLEM
The book specifies that of the two serial conections between R1 and Corp, there should be a DCE on each end..
Both of my DCE's are on the same end.
First lets be sure we understand what DCE means:
networkengineering.stackexchange.com/
One side of the link (DCE), has to transmit the clock signal, which controls the data rate, and the other side (DTE) receives the clock signal.
That is good enough for now. Note that while the book does specify in the diagram that each side should have a DCE, it was not actually mentioned in the configs.
We did not set a DCE or clock rate when conifguring those interfaces.
To fix this in my Packet Tracer topology, I did some quick research:
While this post wasnt pertaining to Packet Tracer, it got me thinking about the cable itself.
I deleted both of my existing serial connections and looked at the options for creating a new cable.
I noticed one is a DCE and one is a DTE:
Fixed the issue
back to the configuration overview: 4 routers, abbreviated show run output
Corp
interface FastEthernet0/0
description connection to R3
ip address 10.1.5.1 255.255.255.0
duplex auto
speed auto
!
interface FastEthernet0/1
no ip address
duplex auto
speed auto
shutdown
!
interface Serial0/0/0
description 1st connection to R1
ip address 10.1.2.1 255.255.255.0
!
interface Serial0/0/1
description 2nd connection to R1
ip address 10.1.3.1 255.255.255.0
clock rate 2000000
!
interface Serial0/1/0
description connection to R2
ip address 10.1.4.1 255.255.255.0
!
interface Vlan1
description Switch Card to Core Network
ip address 10.1.1.1 255.255.255.0
!
interface FastEthernet1/0
description switch port connection to WWW Server
switchport mode access
switchport nonegotiate
!
interface FastEthernet1/1
description switch port connection to Email Server
switchport mode access
switchport nonegotiate
!
interface FastEthernet1/2
description switch port connection to DNS Server
switchport mode access
switchport nonegotiate
!
R1
interface FastEthernet0/0
description connection to Finance
ip address 192.168.10.1 255.255.255.0
duplex auto
speed auto
!
interface FastEthernet0/1
description connection to Marketing
ip address 192.168.20.1 255.255.255.0
duplex auto
speed auto
!
interface Serial0/0/0
description 1st connection to Corp router
ip address 10.1.2.2 255.255.255.0
clock rate 2000000
!
interface Serial0/0/1
description 2nd connecction to Corp router
ip address 10.1.3.2 255.255.255.0
!
R2
interface FastEthernet0/0
description Connection to Sales PC
ip address 192.168.30.1 255.255.255.0
duplex auto
speed auto
!
interface FastEthernet0/1
description Connection to HR PC
ip address 192.168.40.1 255.255.255.0
duplex auto
speed auto
!
interface Serial0/0/0
description Connection to Corp Router
ip address 10.1.4.2 255.255.255.0
clock rate 2000000
!
interface Serial0/0/1
no ip address
clock rate 2000000
shutdown
!
R3
interface FastEthernet0/0
description connection to corp router
ip address 10.1.5.2 255.255.255.0
duplex auto
speed auto
!
interface FastEthernet0/1
no ip address
duplex auto
speed auto
shutdown
!
interface Dot11Radio0/0/0
description WAN for mobile
ip address 172.16.10.1 255.255.255.0
speed 12.0 18.0 24.0 36.0 48.0 54.0 6.0 9.0 basic-1.0 basic-11.0 basic-2.0 basic-5.5
ssid ADMIN2
and here is the output of show ip route for each router
Codes: C - connected, S - static, I - IGRP, R - RIP, M - mobile, B - BGP
D - EIGRP, EX - EIGRP external, O - OSPF, IA - OSPF inter area
N1 - OSPF NSSA external type 1, N2 - OSPF NSSA external type 2
E1 - OSPF external type 1, E2 - OSPF external type 2, E - EGP
i - IS-IS, L1 - IS-IS level-1, L2 - IS-IS level-2, ia - IS-IS inter area
* - candidate default, U - per-user static route, o - ODR
P - periodic downloaded static route
Gateway of last resort is not set
Corp
10.0.0.0/24 is subnetted, 2 subnets
C 10.1.2.0 is directly connected, Serial0/0/0
C 10.1.3.0 is directly connected, Serial0/0/1
C 192.168.10.0/24 is directly connected, FastEthernet0/0
C 192.168.20.0/24 is directly connected, FastEthernet0/1
R1
10.0.0.0/24 is subnetted, 2 subnets
C 10.1.2.0 is directly connected, Serial0/0/0
C 10.1.3.0 is directly connected, Serial0/0/1
C 192.168.10.0/24 is directly connected, FastEthernet0/0
C 192.168.20.0/24 is directly connected, FastEthernet0/1
R2
10.0.0.0/24 is subnetted, 1 subnets
C 10.1.4.0 is directly connected, Serial0/0/0
C 192.168.30.0/24 is directly connected, FastEthernet0/0
C 192.168.40.0/24 is directly connected, FastEthernet0/1
R3
10.0.0.0/8 is variably subnetted, 2 subnets, 2 masks
C 10.1.5.0/24 is directly connected, FastEthernet0/0
L 10.1.5.2/32 is directly connected, FastEthernet0/0
172.16.0.0/16 is variably subnetted, 2 subnets, 2 masks
C 172.16.10.0/24 is directly connected, Dot11Radio0/0/0
L 172.16.10.1/32 is directly connected, Dot11Radio0/0/0
Note that this is before we have configured any 'routing'. We are seeing configured, directly connected networks.
The output for R3 is particularly interesting
What does 'variably' subnetted mean, and what is the "L" next to these routes. And why do they have a mask of 32?
R3
10.0.0.0/8 is variably subnetted, 2 subnets, 2 masks
C 10.1.5.0/24 is directly connected, FastEthernet0/0
L 10.1.5.2/32 is directly connected, FastEthernet0/0
172.16.0.0/16 is variably subnetted, 2 subnets, 2 masks
C 172.16.10.0/24 is directly connected, Dot11Radio0/0/0
L 172.16.10.1/32 is directly connected, Dot11Radio0/0/0
Cisco forums
That makes sense, but my question is why did the other routing tables not behave the same way? R3 is the only one that shows "L" routes.
The book tells us we're using two different model routers, and indeed they are running different IOS versions:
NOTE that at the time the book was published IOS 15 was not released yet, so the book assumes all routers are running 12.4
But that still doesnt explain why Corp and R3 are behaving differently..
Corp
10.0.0.0/24 is subnetted, 2 subnets
C 10.1.2.0 is directly connected, Serial0/0/0
C 10.1.3.0 is directly connected, Serial0/0/1
C 192.168.10.0/24 is directly connected, FastEthernet0/0
C 192.168.20.0/24 is directly connected, FastEthernet0/1
R1
10.0.0.0/24 is subnetted, 2 subnets
C 10.1.2.0 is directly connected, Serial0/0/0
C 10.1.3.0 is directly connected, Serial0/0/1
C 192.168.10.0/24 is directly connected, FastEthernet0/0
C 192.168.20.0/24 is directly connected, FastEthernet0/1
R2
10.0.0.0/24 is subnetted, 1 subnets
C 10.1.4.0 is directly connected, Serial0/0/0
C 192.168.30.0/24 is directly connected, FastEthernet0/0
C 192.168.40.0/24 is directly connected, FastEthernet0/1
R3
10.0.0.0/8 is variably subnetted, 2 subnets, 2 masks
C 10.1.5.0/24 is directly connected, FastEthernet0/0
L 10.1.5.2/32 is directly connected, FastEthernet0/0
172.16.0.0/16 is variably subnetted, 2 subnets, 2 masks
C 172.16.10.0/24 is directly connected, Dot11Radio0/0/0
L 172.16.10.1/32 is directly connected, Dot11Radio0/0/0
how are Corp and R3 different?
The answer is, they are not...
I have accidentally displayed the R1 output to the Corp windows. Error in translating data from the IOS to this webpage..
here's the corrected output.
Corp
10.0.0.0/8 is variably subnetted, 10 subnets, 2 masks
C 10.1.1.0/24 is directly connected, Vlan1
L 10.1.1.1/32 is directly connected, Vlan1
C 10.1.2.0/24 is directly connected, Serial0/0/0
L 10.1.2.1/32 is directly connected, Serial0/0/0
C 10.1.3.0/24 is directly connected, Serial0/0/1
L 10.1.3.1/32 is directly connected, Serial0/0/1
C 10.1.4.0/24 is directly connected, Serial0/1/0
L 10.1.4.1/32 is directly connected, Serial0/1/0
C 10.1.5.0/24 is directly connected, FastEthernet0/0
L 10.1.5.1/32 is directly connected, FastEthernet0/0
R1
10.0.0.0/24 is subnetted, 2 subnets
C 10.1.2.0 is directly connected, Serial0/0/0
C 10.1.3.0 is directly connected, Serial0/0/1
C 192.168.10.0/24 is directly connected, FastEthernet0/0
C 192.168.20.0/24 is directly connected, FastEthernet0/1
R2
10.0.0.0/24 is subnetted, 1 subnets
C 10.1.4.0 is directly connected, Serial0/0/0
C 192.168.30.0/24 is directly connected, FastEthernet0/0
C 192.168.40.0/24 is directly connected, FastEthernet0/1
R3
10.0.0.0/8 is variably subnetted, 2 subnets, 2 masks
C 10.1.5.0/24 is directly connected, FastEthernet0/0
L 10.1.5.2/32 is directly connected, FastEthernet0/0
172.16.0.0/16 is variably subnetted, 2 subnets, 2 masks
C 172.16.10.0/24 is directly connected, Dot11Radio0/0/0
L 172.16.10.1/32 is directly connected, Dot11Radio0/0/0
We do indeed see consistent behavior differences between IOS versions 12.4 and 15.1
recap Corp and R3 outputs:
update topology with Router versions
That covers the first half of Chapter 8. Now we are ready to configure IP routing on our network.
There are three ways: Static, Default, Dynamic
To set up static routes, we simply need to program the routes using the ip route command
Syntax
ip route
[
destination network
]
[
mask
]
[
next hop
]
[
exitinterface
]
[
administrative distance
]
[
permanent
]
destination network and mask
the network data we're adding to the routing table
next-hop address
the address of the next-hop router that will receive the packet and forward to the remote network.
This is the IP address of a router interface that is directly connected.
It must be pingable.
exit interface
can be used instead of next hop address
administrative distance
by default, static routes have an admin distance of 1 if you use a next hop, or 0 if you use exit interface.
You can change the value by adding an administrative weight at the end of the command. More on this later with dynamic routing.
permanent
if the interface is shut down or the router cant communicate to the next hp router, the route will automatically be discarded from the table by default.
The 'permanent' option keeps the entry in the routing table indefenitely.
-----------------------------------------------------------------------------------------------------
Corp has automatically picked up 5 routes that are directly connected:
10.1.1.0 to corp switch card
10.1.2.0 to R1
10.1.3.0 to R1
10.1.4.0 to R2
10.1.5.0 to R3
We need to program 5 more routes:
192.168.10.0 traverse R1
192.168.20.0 traverse R1
192.168.30.0 traverse R1
192.168.40.0 traverse R2
172.16.10.0 traverse R3
-----------------------------------------------------------------------------------------------------
R1 has automatically picked up 4 routes that are directly connected:
10.1.2.0
10.1.3.0
192.168.10.0
192.168.20.0
We need to program 6 more routes:
10.1.1.0
10.1.4.0
10.1.5.0
192.168.30.0
192.168.40.0
172.16.10.0
-----------------------------------------------------------------------------------------------------
R2 has automatically picked up 3 routes that are directly connected:
10.1.4.0
192.168.30.0
192.168.40.0
We need to program 7 more routes:
10.1.1.0
10.1.2.0
10.1.3.0
10.1.5.0
192.168.10.0
192.168.20.0
172.16.10.0
-----------------------------------------------------------------------------------------------------
R3 has automatically picked up 2 routes that are directly connected:
10.1.5.0
172.16.10.0
We need to program 8 more routes:
10.1.1.0
10.1.2.0
10.1.3.0
10.1.4.0
192.168.10.0
192.168.20.0
192.168.30.0
192.168.40.0
Notice the pattern- each router ends up with 10 routes
There are 10 routes total in this topology. AKA ten broadcast domains
Programming the routes
Corp
Corp(config)#
ip route 192.168.10.0 255.255.255.0 10.1.2.2 150
Corp(config)#
ip route 192.168.20.0 255.255.255.0 10.1.3.2 150
Corp(config)#
ip route 192.168.30.0 255.255.255.0 10.1.4.2 150
Corp(config)#
ip route 192.168.40.0 255.255.255.0 10.1.4.2 150
Corp(config)#
ip route 172.16.10.0 255.255.255.0 10.1.5.2 150
Corp(config)#
do show ip route
In the first line, the router is saying that a
classful A network is being subnetted
There are 5 routes directly connected
We see two lines per route (one for the network and one
for the interface(/32)-
10.0.0.0/8 is variably subnetted, 10 subnets, 2 masks
C 10.1.1.0/24 is directly connected, Vlan1
L 10.1.1.1/32 is directly connected, Vlan1
C 10.1.2.0/24 is directly connected, Serial0/0/0
L 10.1.2.1/32 is directly connected, Serial0/0/0
C 10.1.3.0/24 is directly connected, Serial0/0/1
L 10.1.3.1/32 is directly connected, Serial0/0/1
C 10.1.4.0/24 is directly connected, Serial0/1/0
L 10.1.4.1/32 is directly connected, Serial0/1/0
C 10.1.5.0/24 is directly connected, FastEthernet0/0
L 10.1.5.1/32 is directly connected, FastEthernet0/0
and 5 routes that require traversal of a router to reach
172.16.0.0/24 is subnetted, 1 subnets
S 172.16.10.0/24 [150/0] via 10.1.5.2
S 192.168.10.0/24 [150/0] via 10.1.2.2
S 192.168.20.0/24 [150/0] via 10.1.3.2
S 192.168.30.0/24 [150/0] via 10.1.4.2
S 192.168.40.0/24 [150/0] via 10.1.4.2
R1
R1(config)#
ip route 10.1.1.0 255.255.255.0 10.1.2.1 150
R1(config)#
ip route 10.1.4.0 255.255.255.0 10.1.3.1 150
R1(config)#
ip route 10.1.5.0 255.255.255.0 10.1.2.1 150
R1(config)#
ip route 192.168.30.0 255.255.255.0 10.1.3.1 150
R1(config)#
ip route 192.168.40.0 255.255.255.0 10.1.2.1 150
R1(config)#
ip route 172.16.10.0 255.255.255.0 10.1.3.1 150
the only way to get across the corp router is to go into it via 10.1.2.1 or 10.1.3.1
R1(config)#
do show ip route
10.0.0.0/24 is subnetted, 5 subnets
S 10.1.1.0 [150/0] via 10.1.2.1
C 10.1.2.0 is directly connected, Serial0/0/0
C 10.1.3.0 is directly connected, Serial0/0/1
S 10.1.4.0 [150/0] via 10.1.3.1
S 10.1.5.0 [150/0] via 10.1.2.1
172.16.0.0/24 is subnetted, 1 subnets
S 172.16.10.0 [150/0] via 10.1.3.1
C 192.168.10.0/24 is directly connected, FastEthernet0/0
C 192.168.20.0/24 is directly connected, FastEthernet0/1
S 192.168.30.0/24 [150/0] via 10.1.3.1
S 192.168.40.0/24 [150/0] via 10.1.2.1
R2
R2(config)#
iproute 10.1.1.0 255.255.255.0 10.1.4.1 150
R2(config)#
iproute 10.1.2.0 255.255.255.0 10.1.4.1 150
R2(config)#
iproute 10.1.3.0 255.255.255.0 10.1.4.1 150
R2(config)#
iproute 10.1.5.0 255.255.255.0 10.1.4.1 150
R2(config)#
iproute 192.168.10.0 255.255.255.0 10.1.4.1 150
R2(config)#
iproute 192.168.20.0 255.255.255.0 10.1.4.1 150
the only way to get across Corp is to go into it via 10.1.4.1
R2(config)#
do show ip route
10.0.0.0/24 is subnetted, 5 subnets
S 10.1.1.0 [150/0] via 10.1.4.1
S 10.1.2.0 [150/0] via 10.1.4.1
S 10.1.3.0 [150/0] via 10.1.4.1
C 10.1.4.0 is directly connected, Serial0/0/0
S 10.1.5.0 [150/0] via 10.1.4.1
172.16.0.0/24 is subnetted, 1 subnets
S 172.16.10.0 [150/0] via 10.1.4.1
S 192.168.10.0/24 [150/0] via 10.1.4.1
S 192.168.20.0/24 [150/0] via 10.1.4.1
C 192.168.30.0/24 is directly connected, FastEthernet0/0
C 192.168.40.0/24 is directly connected, FastEthernet0/1
R3
R3(config)#
ip route 10.1.1.0 255.255.255.0 fastethernet 0/0 150
R3(config)#
ip route 10.1.2.0 255.255.255.0 fastethernet 0/0 150
R3(config)#
ip route 10.1.3.0 255.255.255.0 fastethernet 0/0 150
R3(config)#
ip route 10.1.4.0 255.255.255.0 fastethernet 0/0 150
R3(config)#
ip route 192.168.10.0 255.255.255.0 fastethernet 0/0 150
R3(config)#
ip route 192.168.20.0 255.255.255.0 fastethernet 0/0 150
R3(config)#
ip route 192.168.30.0 255.255.255.0 fastethernet 0/0 150
R3(config)#
ip route 192.168.40.0 255.255.255.0 fastethernet 0/0 150
the only way to get across Corp is to EXIT R3 via F0/0
R3(config)#
do show ip route
10.0.0.0/8 is variably subnetted, 6 subnets, 2 masks
S 10.1.1.0/24 is directly connected, FastEthernet0/0
S 10.1.2.0/24 is directly connected, FastEthernet0/0
S 10.1.3.0/24 is directly connected, FastEthernet0/0
S 10.1.4.0/24 is directly connected, FastEthernet0/0
C 10.1.5.0/24 is directly connected, FastEthernet0/0
L 10.1.5.2/32 is directly connected, FastEthernet0/0
172.16.0.0/16 is variably subnetted, 2 subnets, 2 masks
C 172.16.10.0/24 is directly connected, Dot11Radio0/0/0
L 172.16.10.1/32 is directly connected, Dot11Radio0/0/0
S 192.168.10.0/24 is directly connected, FastEthernet0/0
S 192.168.20.0/24 is directly connected, FastEthernet0/0
S 192.168.30.0/24 is directly connected, FastEthernet0/0
S 192.168.40.0/24 is directly connected, FastEthernet0/0
before verifying connectivity across the network, we need to make sure all of our hosts are set. The book is giving us the IP addresses for the servers:
Server Gateway 10.1.1.1
ServerWeb 10.1.1.2
ServerEmail 10.1.1.3
ServerDNS 10.1.1.4
Now we can do some testing across the network:
R3#
ping 10.1.2.2
traverse Corp to R1
R3#
ping 10.1.1.1
traverse Corp to a Corp interface we arent directly connected to
R3#
ping 10.1.1.2
traverse Corp to Web server
R3#
ping 10.1.1.3
traverse Corp to Email server
R3#
ping 10.1.1.4
traverse Corp to DNS server
MobileUser
ping 192.168.10.2
traverse R3, Corp, R1 to Finance client
MobileUser
tracert 192.168.10.2
traverse R3, Corp, R1 to Finance client
Tracing route to 192.168.10.2 over a maximum of 30 hops:
1 19 ms 5 ms 20 ms 172.16.10.1
2 20 ms 6 ms 11 ms 10.1.5.1
3 11 ms 15 ms 10 ms 10.1.3.2
4 9 ms 13 ms 22 ms 192.168.10.2
Trace complete.
notice how the trace doesnt count an egress as a hop, only an ingress
ALSO NOTE that tracert is a Windows command.
the IOS equivalent is traceroute
notice how the output differs from the Windows command
R3
traceroute 192.168.10.2
Type escape sequence to abort.
Tracing the route to 192.168.10.2
1 10.1.5.1 0 msec 0 msec 0 msec
2 10.1.2.2 6 msec 0 msec 5 msec
3 192.168.10.2 1 msec 4 msec 3 msec
Default Routing
we could have done this on R3
R3(config)#
ip route 0.0.0.0 0.0.0.0 10.1.5.1
as an alternative to this configuration on R3
R3(config)#
ip route 10.1.1.0 255.255.255.0 fastethernet 0/0 150
R3(config)#
ip route 10.1.2.0 255.255.255.0 fastethernet 0/0 150
R3(config)#
ip route 10.1.3.0 255.255.255.0 fastethernet 0/0 150
R3(config)#
ip route 10.1.4.0 255.255.255.0 fastethernet 0/0 150
R3(config)#
ip route 192.168.10.0 255.255.255.0 fastethernet 0/0 150
R3(config)#
ip route 192.168.20.0 255.255.255.0 fastethernet 0/0 150
R3(config)#
ip route 192.168.30.0 255.255.255.0 fastethernet 0/0 150
R3(config)#
ip route 192.168.40.0 255.255.255.0 fastethernet 0/0 150
the only way to get across Corp is to EXIT R3 via F0/0
This is called default routing. It should only be used on 'stub routers'- those with only one exit path out of the network.
if you try to put a default route on a non-stub router, you could create loops, since there will be more than one path to other routers...
Think of a default route as a static route that uses a wildcard address and mask. The wildcard is 0.0.0.0
to further analyze this comparison, I'm going to remove the routes from R3...
R3(config)#
no ip route 10.1.1.0 255.255.255.0 fastethernet0/0 150
R3(config)#
no ip route 10.1.2.0 255.255.255.0 fastethernet0/0 150
R3(config)#
no ip route 10.1.3.0 255.255.255.0 fastethernet0/0 150
R3(config)#
no ip route 10.1.4.0 255.255.255.0 fastethernet0/0 150
R3(config)#
no ip route 192.168.10.0 255.255.255.0 fastethernet0/0 150
R3(config)#
no ip route 192.168.20.0 255.255.255.0 fastethernet0/0 150
R3(config)#
no ip route 192.168.30.0 255.255.255.0 fastethernet0/0 150
R3(config)#
no ip route 192.168.40.0 255.255.255.0 fastethernet0/0 150
and then set the default route instead.
R3#
ip route 0.0.0.0 0.0.0.0 10.1.5.1 --- ingress at next hop
OR
R3#
ip route 0.0.0.0 0.0.0.0 Fa0/0 --- egress interface
Then compare the output of show ip route
static routes set
R3#
show ip route
Gateway of last resort is not set
10.0.0.0/8 is variably subnetted, 6 subnets, 2 masks
S 10.1.1.0/24 is directly connected, FastEthernet0/0
S 10.1.2.0/24 is directly connected, FastEthernet0/0
S 10.1.3.0/24 is directly connected, FastEthernet0/0
S 10.1.4.0/24 is directly connected, FastEthernet0/0
C 10.1.5.0/24 is directly connected, FastEthernet0/0
L 10.1.5.2/32 is directly connected, FastEthernet0/0
172.16.0.0/16 is variably subnetted, 2 subnets, 2 masks
C 172.16.10.0/24 is directly connected, Dot11Radio0/0/0
L 172.16.10.1/32 is directly connected, Dot11Radio0/0/0
S 192.168.10.0/24 is directly connected, FastEthernet0/0
S 192.168.20.0/24 is directly connected, FastEthernet0/0
S 192.168.30.0/24 is directly connected, FastEthernet0/0
S 192.168.40.0/24 is directly connected, FastEthernet0/0
default route set
R3#
show ip route
Gateway of last resort is 10.1.5.1 to network 0.0.0.0
10.0.0.0/8 is variably subnetted, 2 subnets, 2 masks
C 10.1.5.0/24 is directly connected, FastEthernet0/0
L 10.1.5.2/32 is directly connected, FastEthernet0/0
172.16.0.0/16 is variably subnetted, 2 subnets, 2 masks
C 172.16.10.0/24 is directly connected, Dot11Radio0/0/0
L 172.16.10.1/32 is directly connected, Dot11Radio0/0/0
S* 0.0.0.0/0 [1/0] via 10.1.5.1
two directly connected networks- 10.1.5.0 and 172.16.10.0
anything not included in those networks goes to ingress of attached neighbor Corp 10.1.5.1
in this toplogy, that includes:
192.168.10.0
192.168.20.0
192.168.30.0
192.168.40.0
and
10.1.1.0
10.1.2.0
10.1.3.0
10.1.4.0
RIP Routing Information Protocol
R1(config)#
router ?
bgp Border Gateway Protocol (BGP)
eigrp Enhanced Interior Gateway Routing Protocol (EIGRP)
ospf Open Shortest Path First (OSPF)
rip Routing Information Protocol (RIP)
set RIP on Corp
Corp(config)#
router rip
Corp(config-router)#
network 10.0.0.0
set RIP on R1
R1(config)#
router rip
R1(config-router)#
network 10.0.0.0
R1 routing table
R1(config)#
do show ip route
10.0.0.0/24 is subnetted, 5 subnets
R 10.1.1.0 [120/1] via 10.1.2.1, 00:00:21, Serial0/0/0
[120/1] via 10.1.3.1, 00:00:21, Serial0/0/1
C 10.1.2.0 is directly connected, Serial0/0/0
C 10.1.3.0 is directly connected, Serial0/0/1
R 10.1.4.0 [120/1] via 10.1.2.1, 00:00:21, Serial0/0/0
[120/1] via 10.1.3.1, 00:00:21, Serial0/0/1
R 10.1.5.0 [120/1] via 10.1.2.1, 00:00:21, Serial0/0/0
[120/1] via 10.1.3.1, 00:00:21, Serial0/0/1
172.16.0.0/24 is subnetted, 1 subnets
S 172.16.10.0 [150/0] via 10.1.3.1
C 192.168.10.0/24 is directly connected, FastEthernet0/0
C 192.168.20.0/24 is directly connected, FastEthernet0/1
S 192.168.30.0/24 [150/0] via 10.1.3.1
S 192.168.40.0/24 [150/0] via 10.1.2.1
here's R1 before RIP, with only static routes set:
R1(config)#
do show ip route
10.0.0.0/24 is subnetted, 5 subnets
S 10.1.1.0 [150/0] via 10.1.2.1
C 10.1.2.0 is directly connected, Serial0/0/0
C 10.1.3.0 is directly connected, Serial0/0/1
S 10.1.4.0 [150/0] via 10.1.3.1
S 10.1.5.0 [150/0] via 10.1.2.1
172.16.0.0/24 is subnetted, 1 subnets
S 172.16.10.0 [150/0] via 10.1.3.1
C 192.168.10.0/24 is directly connected, FastEthernet0/0
C 192.168.20.0/24 is directly connected, FastEthernet0/1
S 192.168.30.0/24 [150/0] via 10.1.3.1
S 192.168.40.0/24 [150/0] via 10.1.2.1
These RIP routes are being advertised as available *to other RIP routers*.
CORP is advertisting THREE routes via RIP to R1 right now
10.1.1.0
10.1.4.0
10.1.5.0
access to those networks can be achieved by R1 by going THROUGH CORP via ingress .2.1 or .3.1
The advantage..... is that we didnt statically program these routes
we engaged RIP, on BOTH routers- R1 and Corp, and handed them BOTH the network "10.0.0.0"
So, why did RIP choose to display these particular routes
Keep in mind that the output above is from R1 only... In the context of the R1 ROUTER ONLY,
there are three relevant routes within the "10.0.0.0" parameter we specified. The three routes involve Corp.
Corp is sending RIP data about these routes to Corp.
Lets look closer at how this is happening:
here's our starting point before any RIP is set
here's our routing tables after i set RIP with 10.0.0.0 on both..
FIRST i set it on Corp, then R1.(per the book's instructions) As a result we are seeing RIP routes in R1 only....
then I went back to a fresh packet tracer file with no RIP set. And I set RIP in the opposite order;
FIRST i set it on R1, then Corp. And again, we are seeing RIP routes in R1 only....
I wanted to prove that it didnt matter which order we enabled RIP on the two routers. What matters here is that
we enable RIP on both of them with the criteria of 10.0.0.0
Recall the topology:
if Corp and R1 are set for RIP and given the criteria 10.0.0.0, meaning that we are trying to reach networks
within that range, then it follows that Corp will advertise 1.1.0, 1.4.0, and 1.5.0 to R1, because Corp stands between those networks
and R1
"Hi R1, I'm Corp I have three networks that fall inside 10.0.0.0, and you can reach them through me via .2.1 or .3.1"
It also follows that Corp's routing table shows no RIP routes- because R1 isnt advertising any. R1 doesnt have any networks
in the 10.0.0.0 range that Corp could reach
To further clarify this, we'll proceed with the book's instructions. We'll now set more RIP routes on R1
R1(config)#
router rip
R1(config-router)#
network 192.168.10.0
R1(config-router)#
network 192.168.20.0
Corp routing table before RIP set on R1:
Corp#
show ip route
10.0.0.0/8 is variably subnetted, 10 subnets, 2 masks
C 10.1.1.0/24 is directly connected, Vlan1
L 10.1.1.1/32 is directly connected, Vlan1
C 10.1.2.0/24 is directly connected, Serial0/0/0
L 10.1.2.1/32 is directly connected, Serial0/0/0
C 10.1.3.0/24 is directly connected, Serial0/0/1
L 10.1.3.1/32 is directly connected, Serial0/0/1
C 10.1.4.0/24 is directly connected, Serial0/1/0
L 10.1.4.1/32 is directly connected, Serial0/1/0
C 10.1.5.0/24 is directly connected, FastEthernet0/0
L 10.1.5.1/32 is directly connected, FastEthernet0/0
172.16.0.0/24 is subnetted, 1 subnets
S 172.16.10.0/24 [150/0] via 10.1.5.2
S 192.168.10.0/24 [150/0] via 10.1.2.2
S 192.168.20.0/24 [150/0] via 10.1.3.2
S 192.168.30.0/24 [150/0] via 10.1.4.2
S 192.168.40.0/24 [150/0] via 10.1.4.2
Corp routing table after RIP set on R1:
Gateway of last resort is not set
10.0.0.0/8 is variably subnetted, 10 subnets, 2 masks
C 10.1.1.0/24 is directly connected, Vlan1
L 10.1.1.1/32 is directly connected, Vlan1
C 10.1.2.0/24 is directly connected, Serial0/0/0
L 10.1.2.1/32 is directly connected, Serial0/0/0
C 10.1.3.0/24 is directly connected, Serial0/0/1
L 10.1.3.1/32 is directly connected, Serial0/0/1
C 10.1.4.0/24 is directly connected, Serial0/1/0
L 10.1.4.1/32 is directly connected, Serial0/1/0
C 10.1.5.0/24 is directly connected, FastEthernet0/0
L 10.1.5.1/32 is directly connected, FastEthernet0/0
nothing changed so far
172.16.0.0/24 is subnetted, 1 subnets
S 172.16.10.0/24 [150/0] via 10.1.5.2
no change
R 192.168.10.0/24 [120/1] via 10.1.2.2, 00:00:08, Serial0/0/0
[120/1] via 10.1.3.2, 00:00:08, Serial0/0/1
RIP overrides static- 2 paths available now
R 192.168.20.0/24 [120/1] via 10.1.2.2, 00:00:08, Serial0/0/0
[120/1] via 10.1.3.2, 00:00:08, Serial0/0/1
RIP overrides static- 2 paths available now
S 192.168.30.0/24 [150/0] via 10.1.4.2
no change
S 192.168.40.0/24 [150/0] via 10.1.4.2
no change
"Hi Corp- I'm R1 and I have zero networks
that fall inside 10.0.0.0, however I do have some networks that fall within
192.168.20.0 and 192.168.10.0
and you can reach them through me(R1) if you ingress at .1.2.2 or .1.3.2"
ok, we have the concept down. Time to proceed and set up RIP on R2............
R2(config)#
router rip
R2(config-router)#
network 10.0.0.0
R2(config-router)#
network 192.168.30.0
R2(config-router)#
network 192.168.40.0
R2 before RIP enabled
R2#
show ip route
10.0.0.0/24 is subnetted, 5 subnets
S 10.1.1.0 [150/0] via 10.1.4.1
S 10.1.2.0 [150/0] via 10.1.4.1
S 10.1.3.0 [150/0] via 10.1.4.1
C 10.1.4.0 is directly connected, Serial0/0/0
S 10.1.5.0 [150/0] via 10.1.4.1
172.16.0.0/24 is subnetted, 1 subnets
S 172.16.10.0 [150/0] via 10.1.4.1
S 192.168.10.0/24 [150/0] via 10.1.4.1
S 192.168.20.0/24 [150/0] via 10.1.4.1
C 192.168.30.0/24 is directly connected, FastEthernet0/0
C 192.168.40.0/24 is directly connected, FastEthernet0/1
R2 after RIP added
R2#
show ip route
10.0.0.0/24 is subnetted, 5 subnets
R 10.1.1.0 [120/1] via 10.1.4.1, 00:00:24, Serial0/0/0
from corp
R 10.1.2.0 [120/1] via 10.1.4.1, 00:00:24, Serial0/0/0
from corp
R 10.1.3.0 [120/1] via 10.1.4.1, 00:00:24, Serial0/0/0
from corp
C 10.1.4.0 is directly connected, Serial0/0/0
R 10.1.5.0 [120/1] via 10.1.4.1, 00:00:24, Serial0/0/0
from corp
172.16.0.0/24 is subnetted, 1 subnets
S 172.16.10.0 [150/0] via 10.1.4.1
R 192.168.10.0/24 [120/2] via 10.1.4.1, 00:00:24, Serial0/0/0
from R1 via corp
R 192.168.20.0/24 [120/2] via 10.1.4.1, 00:00:24, Serial0/0/0
from R1 via corp
C 192.168.30.0/24 is directly connected, FastEthernet0/0
C 192.168.40.0/24 is directly connected, FastEthernet0/1
now lets compare the Corp and R1 routing tables- before RIP was set on R2 and after
Corp before R2 RIP
Corp#
show ip route
10.0.0.0/8 is variably subnetted, 10 subnets, 2 masks
C 10.1.1.0/24 is directly connected, Vlan1
L 10.1.1.1/32 is directly connected, Vlan1
C 10.1.2.0/24 is directly connected, Serial0/0/0
L 10.1.2.1/32 is directly connected, Serial0/0/0
C 10.1.3.0/24 is directly connected, Serial0/0/1
L 10.1.3.1/32 is directly connected, Serial0/0/1
C 10.1.4.0/24 is directly connected, Serial0/1/0
L 10.1.4.1/32 is directly connected, Serial0/1/0
C 10.1.5.0/24 is directly connected, FastEthernet0/0
L 10.1.5.1/32 is directly connected, FastEthernet0/0
172.16.0.0/24 is subnetted, 1 subnets
S 172.16.10.0/24 [150/0] via 10.1.5.2
R 192.168.10.0/24 [120/1] via 10.1.2.2, 00:00:02, Serial0/0/0
[120/1] via 10.1.3.2, 00:00:02, Serial0/0/1
R 192.168.20.0/24 [120/1] via 10.1.2.2, 00:00:02, Serial0/0/0
[120/1] via 10.1.3.2, 00:00:02, Serial0/0/1
from R1
S 192.168.30.0/24 [150/0] via 10.1.4.2
S 192.168.40.0/24 [150/0] via 10.1.4.2
Corp after R2 RIP
Corp#
show ip route
10.0.0.0/8 is variably subnetted, 10 subnets, 2 masks
C 10.1.1.0/24 is directly connected, Vlan1
L 10.1.1.1/32 is directly connected, Vlan1
C 10.1.2.0/24 is directly connected, Serial0/0/0
L 10.1.2.1/32 is directly connected, Serial0/0/0
C 10.1.3.0/24 is directly connected, Serial0/0/1
L 10.1.3.1/32 is directly connected, Serial0/0/1
C 10.1.4.0/24 is directly connected, Serial0/1/0
L 10.1.4.1/32 is directly connected, Serial0/1/0
C 10.1.5.0/24 is directly connected, FastEthernet0/0
L 10.1.5.1/32 is directly connected, FastEthernet0/0
172.16.0.0/24 is subnetted, 1 subnets
S 172.16.10.0/24 [150/0] via 10.1.5.2
R 192.168.10.0/24 [120/1] via 10.1.2.2, 00:00:19, Serial0/0/0
[120/1] via 10.1.3.2, 00:00:19, Serial0/0/1
R 192.168.20.0/24 [120/1] via 10.1.2.2, 00:00:19, Serial0/0/0
[120/1] via 10.1.3.2, 00:00:19, Serial0/0/1
from R1
R 192.168.30.0/24 [120/1] via 10.1.4.2, 00:00:15, Serial0/1/0
R 192.168.40.0/24 [120/1] via 10.1.4.2, 00:00:15, Serial0/1/0
from R2
RIP on R2 is advertising .30.0 and .40.0 to Corp
R1 before R2 RIP
R1#
show ip route
10.0.0.0/24 is subnetted, 5 subnets
R 10.1.1.0 [120/1] via 10.1.2.1, 00:00:05, Serial0/0/0
[120/1] via 10.1.3.1, 00:00:05, Serial0/0/1
from Corp
C 10.1.2.0 is directly connected, Serial0/0/0
C 10.1.3.0 is directly connected, Serial0/0/1
R 10.1.4.0 [120/1] via 10.1.2.1, 00:00:05, Serial0/0/0
[120/1] via 10.1.3.1, 00:00:05, Serial0/0/1
R 10.1.5.0 [120/1] via 10.1.2.1, 00:00:05, Serial0/0/0
[120/1] via 10.1.3.1, 00:00:05, Serial0/0/1
from Corp
172.16.0.0/24 is subnetted, 1 subnets
S 172.16.10.0 [150/0] via 10.1.3.1
C 192.168.10.0/24 is directly connected, FastEthernet0/0
C 192.168.20.0/24 is directly connected, FastEthernet0/1
S 192.168.30.0/24 [150/0] via 10.1.3.1
S 192.168.40.0/24 [150/0] via 10.1.2.1
R1 after R2 RIP
R1#
show ip route
10.0.0.0/24 is subnetted, 5 subnets
R 10.1.1.0 [120/1] via 10.1.2.1, 00:00:06, Serial0/0/0
[120/1] via 10.1.3.1, 00:00:06, Serial0/0/1
from Corp
C 10.1.2.0 is directly connected, Serial0/0/0
C 10.1.3.0 is directly connected, Serial0/0/1
R 10.1.4.0 [120/1] via 10.1.2.1, 00:00:06, Serial0/0/0
[120/1] via 10.1.3.1, 00:00:06, Serial0/0/1
R 10.1.5.0 [120/1] via 10.1.2.1, 00:00:06, Serial0/0/0
[120/1] via 10.1.3.1, 00:00:06, Serial0/0/1
from Corp
172.16.0.0/24 is subnetted, 1 subnets
S 172.16.10.0 [150/0] via 10.1.3.1
C 192.168.10.0/24 is directly connected, FastEthernet0/0
C 192.168.20.0/24 is directly connected, FastEthernet0/1
R 192.168.30.0/24 [120/2] via 10.1.3.1, 00:00:06, Serial0/0/1
[120/2] via 10.1.2.1, 00:00:06, Serial0/0/0
R 192.168.40.0/24 [120/2] via 10.1.2.1, 00:00:06, Serial0/0/0
[120/2] via 10.1.3.1, 00:00:06, Serial0/0/1
from R2 via Corp
Now to set RIP on R3
R3(config)#
router rip
R3(config-router)#
network 10.0.0.0
R3(config-router)#
network 172.16.0.0
note that R3 is our only router with "gateway of last resort" set because we set a default route instead of static routes
As a result, we only see directly connected routes listed, along with a single "S*" for the default gateway
R3 before RIP
R3#
show ip route
Gateway of last resort is 10.1.5.1 to network 0.0.0.0
10.0.0.0/8 is variably subnetted, 2 subnets, 2 masks
C 10.1.5.0/24 is directly connected, FastEthernet0/0
L 10.1.5.2/32 is directly connected, FastEthernet0/0
172.16.0.0/16 is variably subnetted, 2 subnets, 2 masks
C 172.16.10.0/24 is directly connected, Dot11Radio0/0/0
L 172.16.10.1/32 is directly connected, Dot11Radio0/0/0
S* 0.0.0.0/0 [1/0] via 10.1.5.1
R3 after RIP
R3#
show ip route
Gateway of last resort is 10.1.5.1 to network 0.0.0.0
-------------------------------------------------------------
10.0.0.0/8 is variably subnetted, 6 subnets, 2 masks
R 10.1.1.0/24 [120/1] via 10.1.5.1, 00:00:21, FastEthernet0/0
R 10.1.2.0/24 [120/1] via 10.1.5.1, 00:00:21, FastEthernet0/0
R 10.1.3.0/24 [120/1] via 10.1.5.1, 00:00:21, FastEthernet0/0
R 10.1.4.0/24 [120/1] via 10.1.5.1, 00:00:21, FastEthernet0/0
from Corp
C 10.1.5.0/24 is directly connected, FastEthernet0/0
L 10.1.5.2/32 is directly connected, FastEthernet0/0
-------------------------------------------------------------
172.16.0.0/16 is variably subnetted, 2 subnets, 2 masks
C 172.16.10.0/24 is directly connected, Dot11Radio0/0/0
L 172.16.10.1/32 is directly connected, Dot11Radio0/0/0
R 192.168.10.0/24 [120/2] via 10.1.5.1, 00:00:21, FastEthernet0/0
R 192.168.20.0/24 [120/2] via 10.1.5.1, 00:00:21, FastEthernet0/0
From R1 via Corp
R 192.168.30.0/24 [120/2] via 10.1.5.1, 00:00:21, FastEthernet0/0
R 192.168.40.0/24 [120/2] via 10.1.5.1, 00:00:21, FastEthernet0/0
From R2 via Corp
S* 0.0.0.0/0 [1/0] via 10.1.5.1
Corp before R3 RIP
Corp#
show ip route
10.0.0.0/8 is variably subnetted, 10 subnets, 2 masks
C 10.1.1.0/24 is directly connected, Vlan1
L 10.1.1.1/32 is directly connected, Vlan1
C 10.1.2.0/24 is directly connected, Serial0/0/0
L 10.1.2.1/32 is directly connected, Serial0/0/0
C 10.1.3.0/24 is directly connected, Serial0/0/1
L 10.1.3.1/32 is directly connected, Serial0/0/1
C 10.1.4.0/24 is directly connected, Serial0/1/0
L 10.1.4.1/32 is directly connected, Serial0/1/0
C 10.1.5.0/24 is directly connected, FastEthernet0/0
L 10.1.5.1/32 is directly connected, FastEthernet0/0
172.16.0.0/24 is subnetted, 1 subnets
S 172.16.10.0/24 [150/0] via 10.1.5.2
R 192.168.10.0/24 [120/1] via 10.1.2.2, 00:00:26, Serial0/0/0
[120/1] via 10.1.3.2, 00:00:26, Serial0/0/1
R 192.168.20.0/24 [120/1] via 10.1.2.2, 00:00:26, Serial0/0/0
[120/1] via 10.1.3.2, 00:00:26, Serial0/0/1
from R1 via corp
R 192.168.30.0/24 [120/1] via 10.1.4.2, 00:00:21, Serial0/1/0
R 192.168.40.0/24 [120/1] via 10.1.4.2, 00:00:21, Serial0/1/0
from R2 via corp
Corp after R3 RIP
Corp#
show ip route
10.0.0.0/8 is variably subnetted, 10 subnets, 2 masks
C 10.1.1.0/24 is directly connected, Vlan1
L 10.1.1.1/32 is directly connected, Vlan1
C 10.1.2.0/24 is directly connected, Serial0/0/0
L 10.1.2.1/32 is directly connected, Serial0/0/0
C 10.1.3.0/24 is directly connected, Serial0/0/1
L 10.1.3.1/32 is directly connected, Serial0/0/1
C 10.1.4.0/24 is directly connected, Serial0/1/0
L 10.1.4.1/32 is directly connected, Serial0/1/0
C 10.1.5.0/24 is directly connected, FastEthernet0/0
L 10.1.5.1/32 is directly connected, FastEthernet0/0
172.16.0.0/16 is variably subnetted, 2 subnets, 2 masks
R 172.16.0.0/16 [120/1] via 10.1.5.2, 00:00:13, FastEthernet0/0
S 172.16.10.0/24 [150/0] via 10.1.5.2
from R3
R 192.168.10.0/24 [120/1] via 10.1.3.2, 00:00:13, Serial0/0/1
[120/1] via 10.1.2.2, 00:00:13, Serial0/0/0
R 192.168.20.0/24 [120/1] via 10.1.3.2, 00:00:13, Serial0/0/1
[120/1] via 10.1.2.2, 00:00:13, Serial0/0/0
from R1 via corp
R 192.168.30.0/24 [120/1] via 10.1.4.2, 00:00:24, Serial0/1/0
R 192.168.40.0/24 [120/1] via 10.1.4.2, 00:00:24, Serial0/1/0
from R2 via corp
R2 before R3 RIP
R2#
show ip route
10.0.0.0/24 is subnetted, 5 subnets
R 10.1.1.0 [120/1] via 10.1.4.1, 00:00:15, Serial0/0/0
R 10.1.2.0 [120/1] via 10.1.4.1, 00:00:15, Serial0/0/0
R 10.1.3.0 [120/1] via 10.1.4.1, 00:00:15, Serial0/0/0
from Corp
C 10.1.4.0 is directly connected, Serial0/0/0
R 10.1.5.0 [120/1] via 10.1.4.1, 00:00:15, Serial0/0/0
from Corp
172.16.0.0/24 is subnetted, 1 subnets
S 172.16.10.0 [150/0] via 10.1.4.1
R 192.168.10.0/24 [120/2] via 10.1.4.1, 00:00:15, Serial0/0/0
R 192.168.20.0/24 [120/2] via 10.1.4.1, 00:00:15, Serial0/0/0
from R1 via Corp
C 192.168.30.0/24 is directly connected, FastEthernet0/0
C 192.168.40.0/24 is directly connected, FastEthernet0/1
R2 after R3 RIP
R2#
show ip route
10.0.0.0/24 is subnetted, 5 subnets
R 10.1.1.0 [120/1] via 10.1.4.1, 00:00:20, Serial0/0/0
R 10.1.2.0 [120/1] via 10.1.4.1, 00:00:20, Serial0/0/0
R 10.1.3.0 [120/1] via 10.1.4.1, 00:00:20, Serial0/0/0
from Corp
C 10.1.4.0 is directly connected, Serial0/0/0
R 10.1.5.0 [120/1] via 10.1.4.1, 00:00:20, Serial0/0/0
from Corp
172.16.0.0/16 is variably subnetted, 2 subnets, 2 masks
R 172.16.0.0/16 [120/2] via 10.1.4.1, 00:00:20, Serial0/0/0
S 172.16.10.0/24 [150/0] via 10.1.4.1
from R3 via Corp
R 192.168.10.0/24 [120/2] via 10.1.4.1, 00:00:20, Serial0/0/0
R 192.168.20.0/24 [120/2] via 10.1.4.1, 00:00:20, Serial0/0/0
from R1 via Corp
C 192.168.30.0/24 is directly connected, FastEthernet0/0
C 192.168.40.0/24 is directly connected, FastEthernet0/1
R1 before R3 RIP
R1#
show ip route
10.0.0.0/24 is subnetted, 5 subnets
R 10.1.1.0 [120/1] via 10.1.2.1, 00:00:04, Serial0/0/0
[120/1] via 10.1.3.1, 00:00:04, Serial0/0/1
C 10.1.2.0 is directly connected, Serial0/0/0
C 10.1.3.0 is directly connected, Serial0/0/1
R 10.1.4.0 [120/1] via 10.1.2.1, 00:00:04, Serial0/0/0
[120/1] via 10.1.3.1, 00:00:04, Serial0/0/1
R 10.1.5.0 [120/1] via 10.1.2.1, 00:00:04, Serial0/0/0
[120/1] via 10.1.3.1, 00:00:04, Serial0/0/1
from Corp
172.16.0.0/24 is subnetted, 1 subnets
S 172.16.10.0 [150/0] via 10.1.3.1
C 192.168.10.0/24 is directly connected, FastEthernet0/0
C 192.168.20.0/24 is directly connected, FastEthernet0/1
R 192.168.30.0/24 [120/2] via 10.1.2.1, 00:00:04, Serial0/0/0
[120/2] via 10.1.3.1, 00:00:04, Serial0/0/1
R 192.168.40.0/24 [120/2] via 10.1.2.1, 00:00:04, Serial0/0/0
[120/2] via 10.1.3.1, 00:00:04, Serial0/0/1
from R2 via Corp
R1 after R3 RIP
R1#
show ip route
10.0.0.0/24 is subnetted, 5 subnets
R 10.1.1.0 [120/1] via 10.1.3.1, 00:00:03, Serial0/0/1
[120/1] via 10.1.2.1, 00:00:03, Serial0/0/0
C 10.1.2.0 is directly connected, Serial0/0/0
C 10.1.3.0 is directly connected, Serial0/0/1
R 10.1.4.0 [120/1] via 10.1.3.1, 00:00:03, Serial0/0/1
[120/1] via 10.1.2.1, 00:00:03, Serial0/0/0
R 10.1.5.0 [120/1] via 10.1.3.1, 00:00:03, Serial0/0/1
[120/1] via 10.1.2.1, 00:00:03, Serial0/0/0
from Corp
172.16.0.0/16 is variably subnetted, 2 subnets, 2 masks
R 172.16.0.0/16 [120/2] via 10.1.3.1, 00:00:03, Serial0/0/1
[120/2] via 10.1.2.1, 00:00:03, Serial0/0/0
S 172.16.10.0/24 [150/0] via 10.1.3.1
from R3 via Corp
C 192.168.10.0/24 is directly connected, FastEthernet0/0
C 192.168.20.0/24 is directly connected, FastEthernet0/1
R 192.168.30.0/24 [120/2] via 10.1.3.1, 00:00:03, Serial0/0/1
[120/2] via 10.1.2.1, 00:00:03, Serial0/0/0
R 192.168.40.0/24 [120/2] via 10.1.3.1, 00:00:03, Serial0/0/1
[120/2] via 10.1.2.1, 00:00:03, Serial0/0/0
from R2 via Corp
Verifying Configurations
in addition to
show ip route
we can also use
show ip protocols
and
debug rip ip
Corp#
show ip protocols
Routing Protocol is "rip"
Sending updates every 30 seconds, next due in 11 seconds
Invalid after 180 seconds, hold down 180, flushed after 240
Outgoing update filter list for all interfaces is not set
Incoming update filter list for all interfaces is not set
Redistributing: rip
Default version control: send version 1, receive any version
Interface Send Recv Triggered RIP Key-chain
Vlan1 1 2 1
FastEthernet0/0 1 2 1
Serial0/0/1 1 2 1
Serial0/1/0 1 2 1
Serial0/0/0 1 2 1
Automatic network summarization is in effect
Maximum path: 4
Routing for Networks:
10.0.0.0
Passive Interface(s):
Routing Information Sources:
Gateway Distance Last Update
10.1.5.2 120 00:00:00
10.1.3.2 120 00:00:10
10.1.2.2 120 00:00:10
10.1.4.2 120 00:00:20
Distance: (default is 120)
R3#
debug ip rip
R3#RIP: received v1 update from 10.1.5.1 on FastEthernet0/0
10.1.1.0 in 1 hops
10.1.2.0 in 1 hops
10.1.3.0 in 1 hops
10.1.4.0 in 1 hops
192.168.10.0 in 2 hops
192.168.20.0 in 2 hops
192.168.30.0 in 2 hops
192.168.40.0 in 2 hops
R3#RIP: sending v1 update to 255.255.255.255 via Dot11Radio0/0/0 (172.16.10.1)
RIP: build update entries
network 10.0.0.0 metric 1
network 192.168.10.0 metric 3
network 192.168.20.0 metric 3
network 192.168.30.0 metric 3
network 192.168.40.0 metric 3
RIP: sending v1 update to 255.255.255.255 via FastEthernet0/0 (10.1.5.2)
RIP: build update entries
network 172.16.0.0 metric 1
output loops until manually disabled..............
R3#
undebug all
All possible debugging has been turned off
Note that due to the Split Horizon rule, R3 is not sending all of it's known RIP data to Corp.
It is sending all known RIP data out of the wifi interface (even there though there's no router that way),
but it is ONLY sending data about the wifi network back to Corp; data that Corp doesnt already have
Now lets look at some examples with sample routers..
I got hung up on these two examples because I found the
wording to be a bit confusing. Also there was subnetting involved that I was able to figure out, but threw me at first
First source of confusion- we have two seperate examples, and I was mixing them up.
The examples are:
Use the debug ip rip command to both:
discover a problem
and figure out how RIP was configured on a router from a different sample network
The conclusion regarding 'figuring out how RIP is configured' on this router, is that RIP networks are set as 10.0.0.0 and 172.16.0.0.
We determined that we are not the 'first source' of info on the 192.168.1.0 nertwork, since it is a metric of 2. We are sending out RIP data on that network,
but that RIP data is made availbale to us via another router.
I also got tripped up on the fact that RA is sending out S0/0 which corresponds 10.0.8.1,
and then receiving on the same interface S0/0 from an ip address of 10.0.15.0 on the other side of the link
I was able to determine that these two address are actually on the same subnet. My initial assumption was that the network address for the link is 10.0.0.0.
The problem doesn't give the subnet mask- I guessed it as /20 by using a 16 block since we can see that the third octet seems to move in 8's
if the network starts at 10.0.0.0 and we use /20 with 16 block, we would indeed have a last host address of 10.0.15.254, so 10.0.15.2 would be a valid host.
So there was a twist to this problem which needed subnetting to solve. It wasnt particulary releveant to the subject of RIP, but I was curious why the address on
the other side of that link looked so strange.
The problem also points out that we can determine there are 'at least' two routers participating in RIP here since we are sending RIP data out two interfaces but
only receiving RIP data on one interface. I'm unclear on why its worded this way; we know we are a RIP router- the fact that we are receiving data on one interface
would suggest there is 'at least one more' RIP router out there.
that's it for this example. Back to the original statement-
Use the debug ip rip command to both discover a problem and figure out
how RIP was configured on a router from a different sample network
We just 'figured out how RIP was configured on a router'.. The second example is regarding 'discovering a problem', although it is mentioned first.
The second example will use debug ip rip and show ip route to find a problem with the network
it looks like RIP data for 172.16.20.0 was received on S0/0, and then that interface was bumped out of the routing table entry for that network in favor of a static route.
ok, moving on now to RIP V2
RIP V2
enable it on all four routers
Corp(config)
router rip
Corp(config-router)
version 2
R1(config)
router rip
R1(config-router)
version 2
R2(config)
router rip
R2(config-router)
version 2
R3(config)
router rip
R3(config-router)
version 2
We'll use R1 to compare RIPv1 and RIPv2
RIPv1
R1(config)
debug ip rip
R1#RIP: sending v1 update to 255.255.255.255 via FastEthernet0/0 (192.168.10.1)
RIP: build update entries
network 10.0.0.0 metric 1
network 172.16.0.0 metric 3
network 192.168.20.0 metric 1
network 192.168.30.0 metric 3
network 192.168.40.0 metric 3
RIP: sending v1 update to 255.255.255.255 via FastEthernet0/1 (192.168.20.1)
RIP: build update entries
network 10.0.0.0 metric 1
network 172.16.0.0 metric 3
network 192.168.10.0 metric 1
network 192.168.30.0 metric 3
network 192.168.40.0 metric 3
RIP: sending v1 update to 255.255.255.255 via Serial0/0/0 (10.1.2.2)
RIP: build update entries
network 10.1.3.0 metric 1
network 192.168.10.0 metric 1
network 192.168.20.0 metric 1
RIP: sending v1 update to 255.255.255.255 via Serial0/0/1 (10.1.3.2)
RIP: build update entries
network 10.1.2.0 metric 1
network 192.168.10.0 metric 1
network 192.168.20.0 metric 1
RIPv2
R1(config)
debug ip rip
R1#RIP: sending v2 update to 224.0.0.9 via FastEthernet0/0 (192.168.10.1)
RIP: build update entries
10.0.0.0/8 via 0.0.0.0, metric 1, tag 0
172.16.0.0/16 via 0.0.0.0, metric 3, tag 0
192.168.20.0/24 via 0.0.0.0, metric 1, tag 0
192.168.30.0/24 via 0.0.0.0, metric 3, tag 0
192.168.40.0/24 via 0.0.0.0, metric 3, tag 0
RIP: sending v2 update to 224.0.0.9 via FastEthernet0/1 (192.168.20.1)
RIP: build update entries
10.0.0.0/8 via 0.0.0.0, metric 1, tag 0
172.16.0.0/16 via 0.0.0.0, metric 3, tag 0
192.168.10.0/24 via 0.0.0.0, metric 1, tag 0
192.168.30.0/24 via 0.0.0.0, metric 3, tag 0
192.168.40.0/24 via 0.0.0.0, metric 3, tag 0
RIP: sending v2 update to 224.0.0.9 via Serial0/0/0 (10.1.2.2)
RIP: build update entries
10.1.3.0/24 via 0.0.0.0, metric 1, tag 0
192.168.10.0/24 via 0.0.0.0, metric 1, tag 0
192.168.20.0/24 via 0.0.0.0, metric 1, tag 0
RIP: sending v2 update to 224.0.0.9 via Serial0/0/1 (10.1.3.2)
RIP: build update entries
10.1.2.0/24 via 0.0.0.0, metric 1, tag 0
192.168.10.0/24 via 0.0.0.0, metric 1, tag 0
192.168.20.0/24 via 0.0.0.0, metric 1, tag 0
R1(config)
show ip protocols
Routing Protocol is "rip"
Sending updates every 30 seconds, next due in 13 seconds
Invalid after 180 seconds, hold down 180, flushed after 240
Outgoing update filter list for all interfaces is not set
Incoming update filter list for all interfaces is not set
Redistributing: rip
Default version control: send version 2, receive 2
Interface Send Recv Triggered RIP Key-chain
FastEthernet0/0 2 2
FastEthernet0/1 2 2
Serial0/0/0 2 2
Serial0/0/1 2 2
Automatic network summarization is in effect
Maximum path: 4
Routing for Networks:
10.0.0.0
192.168.10.0
192.168.20.0
Passive Interface(s):
Routing Information Sources:
Gateway Distance Last Update
10.1.3.1 120 00:00:21
10.1.2.1 120 00:00:21
Distance: (default is 120)
final task of this chapter
Enable a default route out to the internet , and advertise via RIP
R3(config)#
interface s0/1/0 (this is only for example, so I am not adding a serial card to R3)
R3(config-if)#
ip addr 172.16.10.5 255.255.255.252
R3(config-if)#
exit
R3(config)#
ip route 0.0.0.0 0.0.0.0 s0/0
R3(config)#
ip default-network 172.16.0.0 tells other routers via RIP that default WAN route is through R3
Chapter 8 Exam Essentials IP Routing
1. Describe the Basic IP routing process
frame changes at each hop, but packet doesnt change EXCEPT that the TTL field in the IP header decrements
2. List the information required by a router to successfully route packets
destination IP address, location of other routers, possible routers to all remote networks,
the best route to each network, how to maintain and maintain routing info
3. Describe how MAC addresses are used during the routing process
a MAC will never pass a router interface. MACs will change between router interfaces
4. View and interpret the routing table of a router
use show ip route to see the table
a "C" indicates directly connected, an "R" indicates RIP provided the route info, "S" means static
5. differentiate the three types of routing
static- manually configured
dynamic- routers automatically share info via protocol
default- a special route is configured for all traffic without a more specific destination network found in the table
6. Compare and contrast static and dynamic routing
static routing creates no routing update traffic which means less overhead on the routers and links- but it must be
configured manually and can't react if links are lost.
dynamic routing creates update traffic, but it can react to outages and choose the best route when multiple routes exist to the same network
7. Configure static routes at the CLI
route [dest network] [mask] [next hop address OR exit interface] [admin distance] [permanent]
Ex:
Corp(config)#
ip route 192.168.10.0 255.255.255.0 10.1.2.2 150
8. Create a default route
ip route 0.0.0.0 0.0.0.0 [ip address OR exit interface]
Ex:
R3(config)#
ip route 0.0.0.0 0.0.0.0 10.1.5.1 (ingress at Corp router- use if R3 cant identify route)
9. Understand administrative distance and its role in the selection of the best route
an integer from 0 (most trusted) to 255 (no traffic will pass via this route).
All routing protocols are assigned an AD but it can be changed at the CLI
10. Differentiate distance-vector, link-state, and hybrid routing protocols
distance vector- based on hop count (RIP)
link-state- multiple factors such as bandwidth and delay
hybrid- uses both
11. List mechanisms used to prevent routing loops in the network
max hop count, split horizon, route poisoning, holddown counters
12. Describe the counts used the operation of RIP
route update timer- (30) interval between routing updates
route invalid timer- (180, update x 3) before a route is determined invalid
holddown timer-(180) time info is supressed when a link is lost
route flush timer- (240) seconds before invalid and removal
13. Configure RIP routing
router rip
network x.x.x.x
the network(s) you want to advertise from your router. It only works if the other router has RIP enabled.
By enabling RIP, you are able to RECEIVE RIP data from other RIP routers.
by specifying a network, you are SENDING RIP data on that network
14. Identify commands used to verify RIP routing
show ip route will provide contents of the routing table with codes (R, C, S)
debug ip rip will show RIP updates being sent and received
15. Describe the differences between RIPv1 and RIPv2
RIPv1 sends a broadcast (255.255.255.255) every 30 seconds and has an AD of 120.
RIPv1 is classful only, does not send any mask info. No authentication between routers.
RIPv2 sends multicasts (224.0.0.9) every 30 seconds and sends mask info, which allows it to support classless networking, RIPv2 also supports
autentication between routers.
Chapter 8 Written Lab 8.0
1. At the appropriate prompt, create a static route to network 172.16.10.0/24 with a next-hop
gateway of 172.16.20.1 and an administrative distance of 150.
Router(config)#
ip route 172.16.10.0 255.255.255.0 172.16.20.1 150
2. When a PC sends a packet to another PC in a remote network, what destination IP address and MAC address will
be in the frame that it sends to it's default gateway?
the gateway interface MAC and the remote PC's IP
3. At the appropriate prompt, create a default route to 172.16.40.1
Router(config)#
ip route 0.0.0.0 0.0.0.0 172.16.40.1
"to" is the wrong word.. we are going TO any route VIA 172.16.40.1
4. If you are using default routing in a classless environment, what command must also be used?
Router(config)#
ip classless
5. On which type of network is a default route most beneficial?
stub
6. At the appropriate prompt, display the routing table on your router
Router#
show ip route
7. When creating a static or default route, you dont have to use the next-hop ip address;
you can instead use the ____________
exit interface
8. True/False: To reach a destination host, you must know the MAC address of the remote host
false, you need the MAC of your router
9. True/False: To reach a destination host, you must know the IP address of the remote host
true
10. At the appropriate prompt, execute the command required on a DCE serial interface that is not required
on a DTE serial interface
Router(config-if)#
clock rate X
11. At the appropriate prompt, enable RIP routing on the interface with the IP address 10.0.0.1/24
Router(config)#
router rip
Router(config-router)#
network 10.0.0.0
RIPv1 is CLASSFUL only... use the classful mask based on the first octet given
12. At the appropriate prompt, prevent a router from propagating IP information out serial 1
Router(config)#
router rip
Router(config-router)#
passive-interface S0/1
can receive RIP data but will not send
13. What routing loop prevention mechanism sends out a maximum hop count as soon as a link fails?
route poisoning
14. What routing loop prevention mechanism suppresses the resending of routing information to an interface
through which it was received?
split horizon
15. At the appropriate prompt display RIP routing updates as they are sent and received on the router
to the console session
Router#
debug ip rip
to turn it off:
Router#
undebug all
Chapter 8 Hands-on Labs
For these labs we will need a network with three routers.
Lab 8.1 Creating Static routes
first set the interfaces, then program the static routes
LabA(config)#
int s0/0/0
LabA(config-if)#
ip addr 172.16.20.1
LabA(config-if)#
int f0/0
LabA(config-if)#
ip addr 172.16.10.1
-----------------------------------------------------------------
LabA(config)#
ip route 172.16.30.0 255.255.255.0 172.16.20.2
LabA(config)#
ip route 172.16.40.0 255.255.255.0 172.16.20.2
LabB(config)#
int s0/0/0
LabB(config-if)#
ip addr 172.16.20.2
LabB(config-if)#
int s0/0/1
LabB(config-if)#
ip addr 172.16.30.1
-----------------------------------------------------------------
LabB(config)#
ip route 172.16.10.0 255.255.255.0 172.16.20.1
LabB(config)#
ip route 172.16.40.0 255.255.255.0 172.16.30.2
LabC(config)#
int s0/0/0
LabC(config-if)#
ip addr 172.16.30.2
LabC(config-if)#
int f0/0
LabC(config-if)#
ip addr 172.16.40.1
-----------------------------------------------------------------
LabC(config)#
ip route 172.16.10.0 255.255.255.0 172.16.30.1
LabC(config)#
ip route 172.16.20.0 255.255.255.0 172.16.30.1
Lab 8.2 RIP Configuration
remove the static routes, enable and configure RIP with the classful network id that covers the routes you want to advertise
LabA(config)#
no ip route 172.16.30.0 255.255.255.0 172.16.20.2
LabA(config)#
no ip route 172.16.40.0 255.255.255.0 172.16.20.2
LabA(config)#
router rip
LabA(config-router)#
network 172.16.0.0
LabA(config-router)#
do show ip route
Gateway of last resort is not set
172.16.0.0/16 is variably subnetted, 5 subnets, 2 masks
C 172.16.10.0/24 is directly connected, FastEthernet0/0
L 172.16.10.1/32 is directly connected, FastEthernet0/0
C 172.16.20.0/24 is directly connected, Serial0/0/0
L 172.16.20.1/32 is directly connected, Serial0/0/0
R 172.16.30.0/24 [120/1] via 172.16.20.2, 00:00:07, Serial0/0/0
from Lab B
LabB(config)#
no ip route 172.16.10.0 255.255.255.0 172.16.20.1
LabB(config)#
no ip route 172.16.40.0 255.255.255.0 172.16.30.2
LabB(config)#
router rip
LabB(config-router)#
network 172.16.0.0
LabB(config-router)#
do show ip route
Gateway of last resort is not set
172.16.0.0/16 is variably subnetted, 5 subnets, 2 masks
R 172.16.10.0/24 [120/1] via 172.16.20.1, 00:00:13, Serial0/0/0
from LabA
C 172.16.20.0/24 is directly connected, Serial0/0/0
L 172.16.20.2/32 is directly connected, Serial0/0/0
C 172.16.30.0/24 is directly connected, Serial0/0/1
L 172.16.30.1/32 is directly connected, Serial0/0/1
LabC(config)#
no ip route 172.16.10.0 255.255.255.0 172.16.30.1
LabC(config)#
no ip route 172.16.20.0 255.255.255.0 172.16.30.1
LabC(config)#
router rip
LabC(config-router)#
network 172.16.0.0
LabC(config-router)#
do show ip route
Gateway of last resort is not set
172.16.0.0/16 is variably subnetted, 3 subnets, 2 masks
R 172.16.20.0/24 [120/1] via 172.16.30.1, 00:00:05, Serial0/0/0
from LabB
C 172.16.30.0/24 is directly connected, Serial0/0/0
L 172.16.30.2/32 is directly connected, Serial0/0/0
Chapter 8 Review Questions
1. The Acme company uses a router named Gateway to connect to its ISP. The address of the ISP router is 206.143.5.2.
Which three commands could be configured on the gateway router to allow internet access to the entire network?
Set a default route:
Gateway(config)#
ip route 0.0.0.0 0.0.0.0 206.143.5.2 next hop IP
Gateway(config)#
ip route 0.0.0.0 0.0.0.0 S/0 exit interface instead of next hop IP
Gateway(config)#
ip default-network 206.143.5.0 next hop IP
2. What command will prevent RIP routing updates from exiting an interface but will sill allow the interface to receive RIP updates?
Router(config-if)#
passive-interface
3. Which two statemnts are true about ip route 172.16.4.0 255.255.255.0 192.168.4.2?
the command establishes a static route
the default admin distance is used (since we didnt give an AD argument)
4. What two destination addresses will be used by HostA to send data to the HTTPS server as shown in the following network?
MAC of RouterA f0/0 interface
IP address of the server
5. Which two statements are true about this output?
RIP: received v1 update from 192.168.40.2 on S0/1
192.168.50.0 in 16 hops (inaccessible)
RIP: sending v1 update to 255.255.255.255 via F0/0 (192.168.30.1)
RIP: build update entries
network 192.168.20.0 metric 1
network 192.168.40.0 metric 1
network 192.168.50.0 metric 16
RIP: sending v1 update to 255.255.255.255 via S0/1 (192.168.40.1)
true:
there are at least two routers exchanging information
192.168.40.2 will be successful
FALSE
there are three interfaces on the router participating in this update
false because we only see two interfaces represented in the output: S0/1(twice) and F0/0
a ping to 192.168.50.1 will be successful
false because that route has a metric of 16; it's unreachable
6. Describe split horizon
will not advertise a route back the the same router it was learned from
7. Which would be true if HostA is trying to communicate to HostB and interface F0/0 of RouterC goes down, as shown in the graphic?
RouterC will send an ICMP 'destination unreachable type' message to inform HostA that HostB is unreachable
8. Which two statements are true regarding classless routing protocols?
VLSM is permitted
RIPv2 supports classless
9. Which two are true regarding distance-vector vs link-state?
Distance vector sends the whole routing table out all active interfaces(even if a router isnt on the other end)at periodic time intervals
Link-state sends updates containing the state of its own links to all routers in the inter-network
10. Which command display RIP routing updates?
debug ip rip
11. What does RIPv2 use to prvent routing loops?
split horizon stops an update from being send on the same interface it was received
holdown timers allow time for a network to become stable in the case of a flapping link
12. A network administrator views the output from the show ip route command. A network that is advertised
by both RIP and EIGRP appears in the routing table flagged an EIGRP route. Why is the RIP route to this network not used in this routing table?
EIGRP has a lower AD.
RIP=120
OSPP=110
IGRP=110
EIGRP=90
13. You type debug ip rip on your router console and see that 172.16.10.0 is being advertised to you with a metric of 16. What does this mean?
it is inaccessible. in RIP if you see a route advertised with a metric of 16, it's inaccessible
14. What metric does RIPv2 use to find the best path to the remote network?
distance aka hop count
15. The Corporate router receives an IP packet with a source IP address of 192.168.214.20 and a destination address of 192.168.22.3. Looking at the output from the Corp router,
what will the router do with this packet?
Corp# show ip route
[cut]
R 192.168.215.0 [120/2] via 192.168.20.2, Serail0/0
R 192.168.115.0 [120/1] via 192.168.20.0, Serial0/0
R 192.168.30.0 [120/1] via 192.168.20.2, Serial0/0
C 192.168.20.0 is directly connected, Serial0/0
C 192.168.214.0 is directly connected, FastEthernet0/0
Since there is no route to that network, the router will discard the packet and send an ICMP destination unreachable message out F0/0 back the the source network
16. If your routing table has a static, a RIP and an EIGRP route to the same network, which route will be used by default?
Static routes have an admin distance of 1 by default. Unless you change it, a static route will always be used over any other
dynamically learned route.
17. You have the following routing table. Which network will NOT be placed in the neighbor routing table?
R 192.168.30.0/24 [120/1] via 192.168.40.1, Serial 0
C 192.168.40.0/24 is directly connected, Serial 0
172.16.0.0/2 is subnetted, 1 subnets
C 172.16.30.0 is directly connected, Loopback0
R 192.168.20.0/24 [120/1] via 192.168.40.1, Serial 0
R 10.0.0.0/8 [120/15] via 192.168.40.1, Serial 0
C 192.168.50.0/24 is directly connected, Ethernet 0
10.0.0.0 cant be placed in neighboring routing table because it is at 15 hops. 16 hops is invalid in RIP
18. Two connected routers are configured only with RIP. What will be the result when a router receives a routing update that contains a
higher-cost path to a network already in it's routing table?
The router will ignore the update because it is higher cost. When a routing update is received, the router first checks the AD and always chooses
the route with the lowest AD.
19.Which is true about route poisoning?
The router sets the metric for a downed link to "infinity".
20. Which is true about RIPv2?
it has all the same timers as RIPv1
------------------------------------------------------------------------------
END CHAPTER 8
54 hours 1-28 thru 2-14-22
original total 143 hours
11.5 hours review 12-23,24,26-22
review total hours 32
book page 428/822
avg 20 min/page (reading and exercises/labs)
Chapter 9 EIGRP and OSPF
pages 427-502, start 2-14-22-M
What is EIGRP?
Note it's not officially on CCNA 200-301 but it is still important to learn
Enhanced IGRP is a classless, enchanced distance vector protocol that uses the concept of an autonomous system to describe
the set of contigous routers that run the same routing protocol and share routing information.
Features:
Support for IP and IPv6 via protocol-dependent modules (seperate routing tables)
Considered classless
Support for summaries and discontiguous networks
Eficient neighbor discovery
communication via RTP- Reliable Transport Protocol
best path selection via Diffusing Updae Algorithm DUAL
Cisco considers EIGRP a "distance-vector" routing protocol
or an "advanced distance-vector" protocol
or a "hybrid" protocol
Configuring EIGRP on our network
------------------------------------------------------------------------------------------------------------------------------------
Corp(config)#
router eigrp ?
<1-65535> Autonomous system number
Corp(config)#
router eigrp 10
R2(config-router)#
network 10.0.0.0
after eigrp on R1- links from Corp to R1 are up
%DUAL-5-NBRCHANGE: IP-EIGRP 10: Neighbor 10.1.3.2 (Serial0/0/1) is up: new adjacency
%DUAL-5-NBRCHANGE: IP-EIGRP 10: Neighbor 10.1.2.2 (Serial0/0/0) is up: new adjacency
after eigrp on R2- link from Corp to R2 is up
%DUAL-5-NBRCHANGE: IP-EIGRP 10: Neighbor 10.1.4.2 (Serial0/1/0) is up: new adjacency
after eigrp on R3- link from Corp to R3 is up
%DUAL-5-NBRCHANGE: IP-EIGRP 10: Neighbor 10.1.5.2 (FastEthernet0/0) is up: new adjacency
------------------------------------------------------------------------------------------------------------------------------------
R1(config)#
router eigrp 10
R1(config-router)#
network 10.0.0.0
after eigrp on R1- link from R1 to Corp is up
%DUAL-5-NBRCHANGE: IP-EIGRP 10: Neighbor 10.1.3.1 (Serial0/0/1) is up: new adjacency
%DUAL-5-NBRCHANGE: IP-EIGRP 10: Neighbor 10.1.2.1 (Serial0/0/0) is up: new adjacency
R1(config-router)#
network 192.168.10.0
R1(config-router)#
network 192.168.20.0
------------------------------------------------------------------------------------------------------------------------------------
R2(config)#
router eigrp 10
R2(config-router)#
network 10.0.0.0
after eigrp on R2- link from R2 to Corp is up
%DUAL-5-NBRCHANGE: IP-EIGRP 10: Neighbor 10.1.4.1 (Serial0/0/0) is up: new adjacency
R1(config-router)#
network 192.168.30.0
R1(config-router)#
network 192.168.40.0
------------------------------------------------------------------------------------------------------------------------------------
R3(config)#
router eigrp 10
R3(config-router)#
network 10.0.0.0
after eigrp on R3- link from R3 to Corp is up
%DUAL-5-NBRCHANGE: IP-EIGRP 10: Neighbor 10.1.5.1 (FastEthernet0/0) is up: new adjacency
R1(config-router)#
network 172.16.0.0
------------------------------------------------------------------------------------------------------------------------------------
Corp#
show ip route
Gateway of last resort is not set
Gateway of last resort is not set
10.0.0.0/8 is variably subnetted, 10 subnets, 2 masks
C 10.1.1.0/24 is directly connected, Vlan1
L 10.1.1.1/32 is directly connected, Vlan1
C 10.1.2.0/24 is directly connected, Serial0/0/0
L 10.1.2.1/32 is directly connected, Serial0/0/0
C 10.1.3.0/24 is directly connected, Serial0/0/1
L 10.1.3.1/32 is directly connected, Serial0/0/1
C 10.1.4.0/24 is directly connected, Serial0/1/0
L 10.1.4.1/32 is directly connected, Serial0/1/0
C 10.1.5.0/24 is directly connected, FastEthernet0/0
L 10.1.5.1/32 is directly connected, FastEthernet0/0
172.16.0.0/16 is variably subnetted, 2 subnets, 2 masks
R 172.16.0.0/16 [120/1] via 10.1.5.2, 00:00:17, FastEthernet0/0
D 172.16.10.0/24 [90/28160] via 10.1.5.2, 00:00:16, FastEthernet0/0
via R3
D 192.168.10.0/24 [90/2172416] via 10.1.2.2, 00:19:13, Serial0/0/0
[90/2172416] via 10.1.3.2, 00:19:13, Serial0/0/1
D 192.168.20.0/24 [90/2172416] via 10.1.3.2, 00:19:05, Serial0/0/1
[90/2172416] via 10.1.2.2, 00:19:05, Serial0/0/0
via R1
D 192.168.30.0/24 [90/2172416] via 10.1.4.2, 00:01:31, Serial0/1/0
D 192.168.40.0/24 [90/2172416] via 10.1.4.2, 00:01:08, Serial0/1/0
via R2
The "D" routes are for DUAL- Diffusing Update Algorithm, indicating they are EIGRP routes.
Note that we have RIP and EIGRP set currently
------------------------------------------------------------------------------------------------------------------------------------
R1#
show ip route
Gateway of last resort is not set
10.0.0.0/8 is variably subnetted, 6 subnets, 2 masks
D 10.0.0.0/8 is a summary, 00:25:28, Null0
D 10.1.1.0/24 [90/27769856] via 10.1.2.1, 00:31:33, Serial0/0/0
[90/27769856] via 10.1.3.1, 00:31:30, Serial0/0/1
via Corp
C 10.1.2.0/24 is directly connected, Serial0/0/0
C 10.1.3.0/24 is directly connected, Serial0/0/1
D 10.1.4.0/24 [90/2681856] via 10.1.2.1, 00:31:33, Serial0/0/0
[90/2681856] via 10.1.3.1, 00:31:30, Serial0/0/1
D 10.1.5.0/24 [90/2172416] via 10.1.2.1, 00:31:33, Serial0/0/0
[90/2172416] via 10.1.3.1, 00:31:30, Serial0/0/1
via Corp
172.16.0.0/16 is variably subnetted, 2 subnets, 2 masks
R 172.16.0.0/16 [120/2] via 10.1.2.1, 00:00:07, Serial0/0/0
[120/2] via 10.1.3.1, 00:00:07, Serial0/0/1
D 172.16.10.0/24 [90/2172416] via 10.1.2.1, 00:06:31, Serial0/0/0
[90/2172416] via 10.1.3.1, 00:06:31, Serial0/0/1
via Corp
C 192.168.10.0/24 is directly connected, FastEthernet0/0
C 192.168.20.0/24 is directly connected, FastEthernet0/1
D 192.168.30.0/24 [90/2684416] via 10.1.3.1, 00:07:46, Serial0/0/1
[90/2684416] via 10.1.2.1, 00:07:46, Serial0/0/0
D 192.168.40.0/24 [90/2684416] via 10.1.2.1, 00:07:23, Serial0/0/0
[90/2684416] via 10.1.3.1, 00:07:23, Serial0/0/1
via Corp
------------------------------------------------------------------------------------------------------------------------------------
R2#
show ip route
Gateway of last resort is not set
10.0.0.0/8 is variably subnetted, 6 subnets, 2 masks
D 10.0.0.0/8 is a summary, 00:13:09, Null0
D 10.1.1.0/24 [90/27769856] via 10.1.4.1, 00:36:53, Serial0/0/0
D 10.1.2.0/24 [90/2681856] via 10.1.4.1, 00:36:53, Serial0/0/0
D 10.1.3.0/24 [90/2681856] via 10.1.4.1, 00:36:53, Serial0/0/0
via Corp
C 10.1.4.0/24 is directly connected, Serial0/0/0
D 10.1.5.0/24 [90/2172416] via 10.1.4.1, 00:36:53, Serial0/0/0
via Corp
172.16.0.0/16 is variably subnetted, 2 subnets, 2 masks
R 172.16.0.0/16 [120/2] via 10.1.4.1, 00:00:23, Serial0/0/0
D 172.16.10.0/24 [90/2172416] via 10.1.4.1, 00:11:54, Serial0/0/0
via Corp
D 192.168.10.0/24 [90/2684416] via 10.1.4.1, 00:30:51, Serial0/0/0
D 192.168.20.0/24 [90/2684416] via 10.1.4.1, 00:30:43, Serial0/0/0
via Corp
C 192.168.30.0/24 is directly connected, FastEthernet0/0
C 192.168.40.0/24 is directly connected, FastEthernet0/1
------------------------------------------------------------------------------------------------------------------------------------
R3#
show ip route
Gateway of last resort is 10.1.5.1 to network 0.0.0.0
10.0.0.0/8 is variably subnetted, 6 subnets, 2 masks
D 10.1.1.0/24 [90/25628160] via 10.1.5.1, 00:37:20, FastEthernet0/0
D 10.1.2.0/24 [90/2172416] via 10.1.5.1, 00:37:15, FastEthernet0/0
D 10.1.3.0/24 [90/2172416] via 10.1.5.1, 00:37:20, FastEthernet0/0
D 10.1.4.0/24 [90/2172416] via 10.1.5.1, 00:37:20, FastEthernet0/0
via Corp
C 10.1.5.0/24 is directly connected, FastEthernet0/0
L 10.1.5.2/32 is directly connected, FastEthernet0/0
172.16.0.0/16 is variably subnetted, 2 subnets, 2 masks
C 172.16.10.0/24 is directly connected, Dot11Radio0/0/0
L 172.16.10.1/32 is directly connected, Dot11Radio0/0/0
D 192.168.10.0/24 [90/2174976] via 10.1.5.1, 00:31:10, FastEthernet0/0
D 192.168.20.0/24 [90/2174976] via 10.1.5.1, 00:31:02, FastEthernet0/0
via Corp and R1
D 192.168.30.0/24 [90/2174976] via 10.1.5.1, 00:13:28, FastEthernet0/0
D 192.168.40.0/24 [90/2174976] via 10.1.5.1, 00:13:05, FastEthernet0/0
via Corp and R2
S* 0.0.0.0/0 [1/0] via 10.1.5.1
------------------------------------------------------------------------------------------------------------------------------------
turn off auto summary on each router
------------------------------------------------------------------------------------------------------------------------------------
Corp(config)#
router eigrp 10
Corp(config-router)#
no auto-summary
------------------------------------------------------------------------------------------------------------------------------------
R1(config)#
router eigrp 10
R1(config-router)#
no auto-summary
------------------------------------------------------------------------------------------------------------------------------------
R2(config)#
router eigrp 10
R2(config-router)#
no auto-summary
------------------------------------------------------------------------------------------------------------------------------------
R3(config)#
router eigrp 10
R3(config-router)#
no auto-summary
------------------------------------------------------------------------------------------------------------------------------------
compare Corp before and after auto summary turned off
------------------------------------------------------------------------------------------------------------------------------------
auto summary on
Corp#
show ip route
Gateway of last resort is not set
10.0.0.0/8 is variably subnetted, 10 subnets, 2 masks
C 10.1.1.0/24 is directly connected, Vlan1
L 10.1.1.1/32 is directly connected, Vlan1
C 10.1.2.0/24 is directly connected, Serial0/0/0
L 10.1.2.1/32 is directly connected, Serial0/0/0
C 10.1.3.0/24 is directly connected, Serial0/0/1
L 10.1.3.1/32 is directly connected, Serial0/0/1
C 10.1.4.0/24 is directly connected, Serial0/1/0
L 10.1.4.1/32 is directly connected, Serial0/1/0
C 10.1.5.0/24 is directly connected, FastEthernet0/0
L 10.1.5.1/32 is directly connected, FastEthernet0/0
172.16.0.0/16 is variably subnetted, 2 subnets, 2 masks
R 172.16.0.0/16 [120/1] via 10.1.5.2, 00:00:17, FastEthernet0/0
D 172.16.10.0/24 [90/28160] via 10.1.5.2, 00:00:16, FastEthernet0/0
via R3
D 192.168.10.0/24 [90/2172416] via 10.1.2.2, 00:19:13, Serial0/0/0
[90/2172416] via 10.1.3.2, 00:19:13, Serial0/0/1
D 192.168.20.0/24 [90/2172416] via 10.1.3.2, 00:19:05, Serial0/0/1
[90/2172416] via 10.1.2.2, 00:19:05, Serial0/0/0
via R1
D 192.168.30.0/24 [90/2172416] via 10.1.4.2, 00:01:31, Serial0/1/0
D 192.168.40.0/24 [90/2172416] via 10.1.4.2, 00:01:08, Serial0/1/0
via R2
auto summary off
Corp#
show ip route
Gateway of last resort is not set
10.0.0.0/8 is variably subnetted, 10 subnets, 2 masks
C 10.1.1.0/24 is directly connected, Vlan1
L 10.1.1.1/32 is directly connected, Vlan1
C 10.1.2.0/24 is directly connected, Serial0/0/0
L 10.1.2.1/32 is directly connected, Serial0/0/0
C 10.1.3.0/24 is directly connected, Serial0/0/1
L 10.1.3.1/32 is directly connected, Serial0/0/1
C 10.1.4.0/24 is directly connected, Serial0/1/0
L 10.1.4.1/32 is directly connected, Serial0/1/0
C 10.1.5.0/24 is directly connected, FastEthernet0/0
L 10.1.5.1/32 is directly connected, FastEthernet0/0
172.16.0.0/16 is variably subnetted, 2 subnets, 2 masks
R 172.16.0.0/16 [120/1] via 10.1.5.2, 00:00:12, FastEthernet0/0
D 172.16.10.0/24 [90/28160] via 10.1.5.2, 00:45:29, FastEthernet0/0
via R3
D 192.168.10.0/24 [90/2172416] via 10.1.2.2, 00:01:08, Serial0/0/0
[90/2172416] via 10.1.3.2, 00:01:08, Serial0/0/1
D 192.168.20.0/24 [90/2172416] via 10.1.2.2, 00:01:08, Serial0/0/0
[90/2172416] via 10.1.3.2, 00:01:08, Serial0/0/1
via R1
D 192.168.30.0/24 [90/2172416] via 10.1.4.2, 00:00:46, Serial0/1/0
D 192.168.40.0/24 [90/2172416] via 10.1.4.2, 00:00:46, Serial0/1/0
via R2
We are still seeing an auto summarized route- 172.16.0.0 coming from R3.
The book discusses enabling EIGRP auto summary on all four routers- nothing is said about disabling it within RIP or turning off RIP.
RIP auto summarizes by default. We cant get rid of this auto summary route while RIP is on.
Moving on...
VERIFYING EIGRP
several commands available to verify and troubleshoot
show ip route
show the entire routing table
show ip route eigrp
show only EIGRP entries in the routing table
show ip eigrp neighbors
show all EIGRP neigbors
show ip eigrp topology
show entries in the EIGRP topology table
show ip protocols
shows routing protocols configuration
debug eigrp packet
shows hello packets sent/received between adjacent routers
debug ip eigrp events
shows EIGRP changes and updates as they occur on your network
lets take a look at the state of our 4 routers. RIP and EIGRP are running on each.
Notice how this command is giving different outputs between the two different IOS versions
IOS 15.1
Corp#
show ip protocols
Routing Protocol is "eigrp 10 "
Outgoing update filter list for all interfaces is not set
Incoming update filter list for all interfaces is not set
Default networks flagged in outgoing updates
Default networks accepted from incoming updates
Redistributing: eigrp 10
EIGRP-IPv4 Protocol for AS(10)
Metric weight K1=1, K2=0, K3=1, K4=0, K5=0
NSF-aware route hold timer is 240
Router-ID: 10.1.1.1
Topology : 0 (base)
Active Timer: 3 min
Distance: internal 90 external 170
Maximum path: 4
Maximum hopcount 100
Maximum metric variance 1
Automatic Summarization: disabled
Automatic address summarization:
Maximum path: 4
Routing for Networks:
10.0.0.0
Routing Information Sources:
Gateway Distance Last Update
10.1.5.2 90 0
10.1.3.2 90 6464
10.1.2.2 90 6795
10.1.4.2 90 7955
Distance: internal 90 external 170
Routing Protocol is "rip"
Sending updates every 30 seconds, next due in 10 seconds
Invalid after 180 seconds, hold down 180, flushed after 240
Outgoing update filter list for all interfaces is not set
Incoming update filter list for all interfaces is not set
Redistributing: rip
Default version control: send version 2, receive 2
Interface Send Recv Triggered RIP Key-chain
Vlan1 2 2
FastEthernet0/0 2 2
Serial0/1/0 2 2
Serial0/0/1 2 2
Serial0/0/0 2 2
Automatic network summarization is in effect
Maximum path: 4
Routing for Networks:
10.0.0.0
Passive Interface(s):
Routing Information Sources:
Gateway Distance Last Update
10.1.5.2 120 00:00:12
10.1.3.2 120 00:00:16
10.1.2.2 120 00:00:16
10.1.4.2 120 00:00:13
Distance: (default is 120)
IOS 12.4
R1#
show ip protocols
Routing Protocol is "eigrp 10 "
Outgoing update filter list for all interfaces is not set
Incoming update filter list for all interfaces is not set
Default networks flagged in outgoing updates
Default networks accepted from incoming updates
EIGRP metric weight K1=1, K2=0, K3=1, K4=0, K5=0
EIGRP maximum hopcount 100
EIGRP maximum metric variance 1
Redistributing: eigrp 10
Automatic network summarization is not in effect
Maximum path: 4
Routing for Networks:
10.0.0.0
192.168.10.0
192.168.20.0
Routing Information Sources:
Gateway Distance Last Update
10.1.3.1 90 6465
10.1.2.1 90 6794
Distance: internal 90 external 170
Routing Protocol is "rip"
Sending updates every 30 seconds, next due in 21 seconds
Invalid after 180 seconds, hold down 180, flushed after 240
Outgoing update filter list for all interfaces is not set
Incoming update filter list for all interfaces is not set
Redistributing: rip
Default version control: send version 2, receive 2
Interface Send Recv Triggered RIP Key-chain
FastEthernet0/0 2 2
FastEthernet0/1 2 2
Serial0/0/0 2 2
Serial0/0/1 2 2
Automatic network summarization is not in effect
Maximum path: 4
Routing for Networks:
10.0.0.0
192.168.10.0
192.168.20.0
Passive Interface(s):
Routing Information Sources:
Gateway Distance Last Update
10.1.3.1 120 00:00:06
10.1.2.1 120 00:00:06
Distance: (default is 120)
IOS 12.4
R2#
show ip protocols
Routing Protocol is "eigrp 10 "
Outgoing update filter list for all interfaces is not set
Incoming update filter list for all interfaces is not set
Default networks flagged in outgoing updates
Default networks accepted from incoming updates
EIGRP metric weight K1=1, K2=0, K3=1, K4=0, K5=0
EIGRP maximum hopcount 100
EIGRP maximum metric variance 1
Redistributing: eigrp 10
Automatic network summarization is not in effect
Maximum path: 4
Routing for Networks:
10.0.0.0
192.168.30.0
192.168.40.0
Routing Information Sources:
Gateway Distance Last Update
10.1.4.1 90 7955
Distance: internal 90 external 170
Routing Protocol is "rip"
Sending updates every 30 seconds, next due in 11 seconds
Invalid after 180 seconds, hold down 180, flushed after 240
Outgoing update filter list for all interfaces is not set
Incoming update filter list for all interfaces is not set
Redistributing: rip
Default version control: send version 2, receive 2
Interface Send Recv Triggered RIP Key-chain
FastEthernet0/0 2 2
FastEthernet0/1 2 2
Serial0/0/0 2 2
Automatic network summarization is in effect
Maximum path: 4
Routing for Networks:
10.0.0.0
192.168.30.0
192.168.40.0
Passive Interface(s):
Routing Information Sources:
Gateway Distance Last Update
10.1.4.1 120 00:00:20
Distance: (default is 120)
IOS 15.1
R3#
show ip protocols
Routing Protocol is "eigrp 10 "
Outgoing update filter list for all interfaces is not set
Incoming update filter list for all interfaces is not set
Default networks flagged in outgoing updates
Default networks accepted from incoming updates
Redistributing: eigrp 10
EIGRP-IPv4 Protocol for AS(10)
Metric weight K1=1, K2=0, K3=1, K4=0, K5=0
NSF-aware route hold timer is 240
Router-ID: 10.1.5.2
Topology : 0 (base)
Active Timer: 3 min
Distance: internal 90 external 170
Maximum path: 4
Maximum hopcount 100
Maximum metric variance 1
Automatic Summarization: disabled
Automatic address summarization:
Maximum path: 4
Routing for Networks:
10.0.0.0
172.16.0.0
Routing Information Sources:
Gateway Distance Last Update
10.1.5.1 90 0
Distance: internal 90 external 170
Routing Protocol is "rip"
Sending updates every 30 seconds, next due in 27 seconds
Invalid after 180 seconds, hold down 180, flushed after 240
Outgoing update filter list for all interfaces is not set
Incoming update filter list for all interfaces is not set
Redistributing: rip
Default version control: send version 2, receive 2
Interface Send Recv Triggered RIP Key-chain
Dot11Radio0/0/0 2 2
FastEthernet0/0 2 2
Automatic network summarization is not in effect
Maximum path: 4
Routing for Networks:
10.0.0.0
172.16.0.0
Passive Interface(s):
Routing Information Sources:
Gateway Distance Last Update
10.1.5.1 120 00:00:02
Distance: (default is 120)
I'm also noticing that we have inconsistent auto-summarization settings- I was having trouble with this earlier. The book discusses
getting rid of the 172.16.0.0 summarized route in the EIGRP settings. I was not able to get rid of it, I think because RIP is still on, and RIP forces auto-summary
Part of the challenge here is that the book is strictly dealing with IOS 12.4
I will now make sure to turn auto summary off for both RIP and EIGRP on each of the four routers.
OK the part I am forgetting is that we are running RIP V2 which does not force auto-summary but runs it optionally, and we must turn it off to avoid auto summarization.
Corp(config)#
router rip
Corp(config-router)#
no auto-summary
Corp(config-router)#
router eigrp 10
Corp(config-router)#
no auto-summary
R1(config)#
router rip
R1(config-router)#
no auto-summary
R1(config-router)#
router eigrp 10
R1(config-router)#
no auto-summary
R1(config)#
router rip
R1(config-router)#
no auto-summary
R1(config-router)#
router eigrp 10
R2(config-router)#
no auto-summary
R3(config)#
router rip
R3(config-router)#
no auto-summary
R3(config-router)#
router eigrp 10
R3(config-router)#
no auto-summary
and lets see how the output looks now. This time I'll do show ip protocols and
show ip route side by side for each router
IOS 15.1
Corp#
show ip protocols
Routing Protocol is "eigrp 10 "
Outgoing update filter list for all interfaces is not set
Incoming update filter list for all interfaces is not set
Default networks flagged in outgoing updates
Default networks accepted from incoming updates
Redistributing: eigrp 10
EIGRP-IPv4 Protocol for AS(10)
Metric weight K1=1, K2=0, K3=1, K4=0, K5=0
NSF-aware route hold timer is 240
Router-ID: 10.1.1.1
Topology : 0 (base)
Active Timer: 3 min
Distance: internal 90 external 170
Maximum path: 4
Maximum hopcount 100
Maximum metric variance 1
Automatic Summarization: disabled
Automatic address summarization:
Maximum path: 4
Routing for Networks:
10.0.0.0
Routing Information Sources:
Gateway Distance Last Update
10.1.5.2 90 0
10.1.3.2 90 6464
10.1.2.2 90 6795
10.1.4.2 90 7955
Distance: internal 90 external 170
Routing Protocol is "rip" doesnt necessarily mean RIPv1
Sending updates every 30 seconds, next due in 3 seconds
Invalid after 180 seconds, hold down 180, flushed after 240
Outgoing update filter list for all interfaces is not set
Incoming update filter list for all interfaces is not set
Redistributing: rip
Default version control: send version 2, receive 2 RIPv2 is specified
Interface Send Recv Triggered RIP Key-chain
Vlan1 2 2
FastEthernet0/0 2 2
Serial0/1/0 2 2
Serial0/0/1 2 2
Serial0/0/0 2 2
Automatic network summarization is not in effect
Maximum path: 4
Routing for Networks:
10.0.0.0
Passive Interface(s):
Routing Information Sources:
Gateway Distance Last Update
10.1.5.2 120 00:00:02
10.1.3.2 120 00:00:21
10.1.2.2 120 00:00:21
10.1.4.2 120 00:00:04
Distance: (default is 120)
IOS 15.1
Corp#
show ip route
Gateway of last resort is not set
10.0.0.0/8 is variably subnetted, 10 subnets, 2 masks
C 10.1.1.0/24 is directly connected, Vlan1
L 10.1.1.1/32 is directly connected, Vlan1
C 10.1.2.0/24 is directly connected, Serial0/0/0
L 10.1.2.1/32 is directly connected, Serial0/0/0
C 10.1.3.0/24 is directly connected, Serial0/0/1
L 10.1.3.1/32 is directly connected, Serial0/0/1
C 10.1.4.0/24 is directly connected, Serial0/1/0
L 10.1.4.1/32 is directly connected, Serial0/1/0
C 10.1.5.0/24 is directly connected, FastEthernet0/0
L 10.1.5.1/32 is directly connected, FastEthernet0/0
172.16.0.0/24 is subnetted, 1 subnets
D 172.16.10.0/24 [90/28160] via 10.1.5.2, 00:57:25, FastEthernet0/0
D 192.168.10.0/24 [90/2172416] via 10.1.3.2, 00:57:20, Serial0/0/1
[90/2172416] via 10.1.2.2, 00:57:20, Serial0/0/0
D 192.168.20.0/24 [90/2172416] via 10.1.3.2, 00:57:20, Serial0/0/1
[90/2172416] via 10.1.2.2, 00:57:20, Serial0/0/0
D 192.168.30.0/24 [90/2172416] via 10.1.4.2, 00:57:19, Serial0/1/0
D 192.168.40.0/24 [90/2172416] via 10.1.4.2, 00:57:19, Serial0/1/0
IOS 12.4
R1#
show ip protocols
Routing Protocol is "eigrp 10 "
Outgoing update filter list for all interfaces is not set
Incoming update filter list for all interfaces is not set
Default networks flagged in outgoing updates
Default networks accepted from incoming updates
EIGRP metric weight K1=1, K2=0, K3=1, K4=0, K5=0
EIGRP maximum hopcount 100
EIGRP maximum metric variance 1
Redistributing: eigrp 10
Automatic network summarization is not in effect
Maximum path: 4
Routing for Networks:
10.0.0.0
192.168.10.0
192.168.20.0
Routing Information Sources:
Gateway Distance Last Update
10.1.3.1 90 6465
10.1.2.1 90 6794
Distance: internal 90 external 170
Routing Protocol is "rip"
Sending updates every 30 seconds, next due in 26 seconds
Invalid after 180 seconds, hold down 180, flushed after 240
Outgoing update filter list for all interfaces is not set
Incoming update filter list for all interfaces is not set
Redistributing: rip
Default version control: send version 2, receive 2
Interface Send Recv Triggered RIP Key-chain
FastEthernet0/0 2 2
FastEthernet0/1 2 2
Serial0/0/0 2 2
Serial0/0/1 2 2
Automatic network summarization is not in effect
Maximum path: 4
Routing for Networks:
10.0.0.0
192.168.10.0
192.168.20.0
Passive Interface(s):
Routing Information Sources:
Gateway Distance Last Update
10.1.3.1 120 00:00:03
10.1.2.1 120 00:00:03
Distance: (default is 120)
IOS 12.4
R1#
show ip route
Gateway of last resort is not set
10.0.0.0/24 is subnetted, 5 subnets
D 10.1.1.0 [90/27769856] via 10.1.3.1, 00:54:47, Serial0/0/1
[90/27769856] via 10.1.2.1, 00:54:47, Serial0/0/0
C 10.1.2.0 is directly connected, Serial0/0/0
C 10.1.3.0 is directly connected, Serial0/0/1
D 10.1.4.0 [90/2681856] via 10.1.3.1, 00:54:47, Serial0/0/1
[90/2681856] via 10.1.2.1, 00:54:47, Serial0/0/0
D 10.1.5.0 [90/2172416] via 10.1.3.1, 00:54:47, Serial0/0/1
[90/2172416] via 10.1.2.1, 00:54:47, Serial0/0/0
172.16.0.0/24 is subnetted, 1 subnets
D 172.16.10.0 [90/2172416] via 10.1.3.1, 00:54:47, Serial0/0/1
[90/2172416] via 10.1.2.1, 00:54:47, Serial0/0/0
C 192.168.10.0/24 is directly connected, FastEthernet0/0
C 192.168.20.0/24 is directly connected, FastEthernet0/1
D 192.168.30.0/24 [90/2684416] via 10.1.3.1, 00:54:46, Serial0/0/1
[90/2684416] via 10.1.2.1, 00:54:46, Serial0/0/0
D 192.168.40.0/24 [90/2684416] via 10.1.3.1, 00:54:46, Serial0/0/1
[90/2684416] via 10.1.2.1, 00:54:46, Serial0/0/0
note that the DUAL routes being advertised from the 10.0.0.0 networks are all specific to the third octet.. that's because we are reading those routes
from their source, aka the router which they are directly connected to, Corp.
and on Corp, those networks were added to the interfaces with a /24 mask.
so even though our EIGRP config doesnt specifically include /24 networks.. we told it to include anything with a 10.x.x.x
Corp is advertising to R1 our /24 network interfaces that have a 10 in the first octet, EXCEPT the two which are directly connected to R1
10.1.1.0
10.1.4.0
10.1.5.0
are assumed to be the subnets based on the info we configured, which was 10.1.4.1/24 on corp, and 10.1.4.2/24 on r2 s0/0/0
nowhere in this configuration, have we entered the 10.1.4.0 network.
EIGRP is figuring it out based on the /24 mask we gave when assiging he IPs to the interfaces
IOS 12.4
R2#
show ip protocols
Routing Protocol is "eigrp 10 "
Outgoing update filter list for all interfaces is not set
Incoming update filter list for all interfaces is not set
Default networks flagged in outgoing updates
Default networks accepted from incoming updates
EIGRP metric weight K1=1, K2=0, K3=1, K4=0, K5=0
EIGRP maximum hopcount 100
EIGRP maximum metric variance 1
Redistributing: eigrp 10
Automatic network summarization is not in effect
Maximum path: 4
Routing for Networks:
10.0.0.0
192.168.30.0
192.168.40.0
Routing Information Sources:
Gateway Distance Last Update
10.1.4.1 90 7955
Distance: internal 90 external 170
Routing Protocol is "rip"
Sending updates every 30 seconds, next due in 18 seconds
Invalid after 180 seconds, hold down 180, flushed after 240
Outgoing update filter list for all interfaces is not set
Incoming update filter list for all interfaces is not set
Redistributing: rip
Default version control: send version 2, receive 2
Interface Send Recv Triggered RIP Key-chain
FastEthernet0/0 2 2
FastEthernet0/1 2 2
Serial0/0/0 2 2
Automatic network summarization is not in effect
Maximum path: 4
Routing for Networks:
10.0.0.0
192.168.30.0
192.168.40.0
Passive Interface(s):
Routing Information Sources:
Gateway Distance Last Update
10.1.4.1 120 00:00:07
Distance: (default is 120)
IOS 12.4
R2#
show ip route
Gateway of last resort is not set
10.0.0.0/24 is subnetted, 5 subnets
D 10.1.1.0 [90/27769856] via 10.1.4.1, 00:59:10, Serial0/0/0
D 10.1.2.0 [90/2681856] via 10.1.4.1, 00:59:10, Serial0/0/0
D 10.1.3.0 [90/2681856] via 10.1.4.1, 00:59:10, Serial0/0/0
C 10.1.4.0 is directly connected, Serial0/0/0
D 10.1.5.0 [90/2172416] via 10.1.4.1, 00:59:10, Serial0/0/0
172.16.0.0/24 is subnetted, 1 subnets
D 172.16.10.0 [90/2172416] via 10.1.4.1, 00:59:10, Serial0/0/0
D 192.168.10.0/24 [90/2684416] via 10.1.4.1, 00:59:10, Serial0/0/0
D 192.168.20.0/24 [90/2684416] via 10.1.4.1, 00:59:10, Serial0/0/0
C 192.168.30.0/24 is directly connected, FastEthernet0/0
C 192.168.40.0/24 is directly connected, FastEthernet0/1
IOS 15.1
R3#
show ip protocols
Routing Protocol is "eigrp 10 "
Outgoing update filter list for all interfaces is not set
Incoming update filter list for all interfaces is not set
Default networks flagged in outgoing updates
Default networks accepted from incoming updates
Redistributing: eigrp 10
EIGRP-IPv4 Protocol for AS(10)
Metric weight K1=1, K2=0, K3=1, K4=0, K5=0
NSF-aware route hold timer is 240
Router-ID: 10.1.5.2
Topology : 0 (base)
Active Timer: 3 min
Distance: internal 90 external 170
Maximum path: 4
Maximum hopcount 100
Maximum metric variance 1
Automatic Summarization: disabled
Automatic address summarization:
Maximum path: 4
Routing for Networks:
10.0.0.0
172.16.0.0
Routing Information Sources:
Gateway Distance Last Update
10.1.5.1 90 0
Distance: internal 90 external 170
Routing Protocol is "rip"
Sending updates every 30 seconds, next due in 15 seconds
Invalid after 180 seconds, hold down 180, flushed after 240
Outgoing update filter list for all interfaces is not set
Incoming update filter list for all interfaces is not set
Redistributing: rip
Default version control: send version 2, receive 2
Interface Send Recv Triggered RIP Key-chain
Dot11Radio0/0/0 2 2
FastEthernet0/0 2 2
Automatic network summarization is not in effect
Maximum path: 4
Routing for Networks:
10.0.0.0
172.16.0.0
Passive Interface(s):
Routing Information Sources:
Gateway Distance Last Update
10.1.5.1 120 00:00:14
Distance: (default is 120)
IOS 15.1
R3#
show ip route
Gateway of last resort is 10.1.5.1 to network 0.0.0.0
10.0.0.0/8 is variably subnetted, 6 subnets, 2 masks
D 10.1.1.0/24 [90/25628160] via 10.1.5.1, 00:59:52, FastEthernet0/0
D 10.1.2.0/24 [90/2172416] via 10.1.5.1, 00:59:47, FastEthernet0/0
D 10.1.3.0/24 [90/2172416] via 10.1.5.1, 00:59:52, FastEthernet0/0
D 10.1.4.0/24 [90/2172416] via 10.1.5.1, 00:59:52, FastEthernet0/0
C 10.1.5.0/24 is directly connected, FastEthernet0/0
L 10.1.5.2/32 is directly connected, FastEthernet0/0
172.16.0.0/16 is variably subnetted, 2 subnets, 2 masks
C 172.16.10.0/24 is directly connected, Dot11Radio0/0/0
L 172.16.10.1/32 is directly connected, Dot11Radio0/0/0
D 192.168.10.0/24 [90/2174976] via 10.1.5.1, 00:59:47, FastEthernet0/0
D 192.168.20.0/24 [90/2174976] via 10.1.5.1, 00:59:47, FastEthernet0/0
D 192.168.30.0/24 [90/2174976] via 10.1.5.1, 00:59:46, FastEthernet0/0
D 192.168.40.0/24 [90/2174976] via 10.1.5.1, 00:59:46, FastEthernet0/0
S* 0.0.0.0/0 [1/0] via 10.1.5.1
Observations:
Since this is a 15.1 router, we always get a "L" local route when
we have a "C" connected route. In R3's case, the 172.16.10.0 network
is directly connected. The interface which connects it, 172.16.10.1,
counts as a "local" route. This is NOT the case on the 12.4 routers.
looking to the left, our protocol output tells us two key facts for both EIGRP and RIP:
Routing for networks:
10.0.0.0
172.16.0.0
R3 is responsible for *sending* data about these two networks to our other EIGRP routers...
"I'm R3 and I can connect you to networks on the R3
router or networks on the Corp router"
Notice how the 192 networks arent listed. R3 isnt connected to a 192 network directly, nor is it connected to a neighbor who is directly connected.
If I, as a client, am sending data to a 192 network from the 172 network, I will start
at R3. Since R3 is receiving routes for the 192 networks via Corp, I will be able to reach a 192 network via Corp.
My connection to corp will happen VIA a "10.0.0.0" route.
R3 is technically only routing for 172 and 10 networks. Beyond that, it could potentially connect to many other different networks. But in terms of the R3 routing table,
all it can offer is a path out to the 172 network or the 10 network
Routing information sources:
10.1.5.1
In this case I can see that R3 is receiving routing data from one interface only,
and that is it's link to Corp. Some of the data we are receiving from Corp actually originates
at other routers, but we cant see that here; the data comes to us from Corp, and that is all we know
EIGRP TERMINOLOGY
FEASIBLE DISTANCE (FD)
the best metric among all paths, including to the next hop neighbor. You will only see the route with the lowest FD appear in the routing table
The FD is calculated by adding the reported distance from the neighbor (AD) plus the metric to that neighbor
ADVERTISED DISTANCE (AD)
the metric of a remote network as reported by a neighbor, listed second in parenthesis in toplogy table
P 192.168.20.0/24, 2 successors, FD is 2172416
via 10.1.3.2 (2172416/28160), Serial0/0/1
feasible / advertised
Neighbor Table
each router keeps state information about adjacent neighbors.. When a new neighbor is learned, the address and interface are recorded.
The neighbor table is stored in RAM.
Sequence numbres are used to match acks with update packets. The last squence number received from a neighbor is recorded so out of order packets
can be detected
Topology Table
acted upon by DUAL Diffusing Update Alogorithm. Contains all destinations advertised by neighboring routers.
For each neighbor, the adversited distance, which comes only from that neighbor's routing table, is recorded
The feasible distance is also recorded.
Feasible Successor
a PATH whose advertised distance is less than the feasible distance of the current succesor, and is considered a backup route.
EIGRP keeps up to 16 feasible successors in the toplogy table.
The one with the best metric (The Successor) is copied and placed into the routing table
Successor
the best route to a remote network, used by EIGRP to forward traffic. It's backed up by a feasible successor, if one is available.
lets demo some more of the commands
VERIFYING EIGRP
several commands available to verify and troubleshoot
show ip route
show the entire routing table
show ip route eigrp
show only EIGRP entries in the routing table
show ip eigrp neighbors
show all EIGRP neigbors
show ip eigrp topology
show entries in the EIGRP topology table
show ip protocols
shows routing protocols configuration
debug eigrp packet
shows hello packets sent/received between adjacent routers
debug ip eigrp events
shows EIGRP changes and updates as they occur on your network
Corp#
show ip eigrp ?
interfaces IP-EIGRP interfaces
neighbors IP-EIGRP neighbors
topology IP-EIGRP Topology Table
traffic IP-EIGRP Traffic Statistics
Corp#
show ip eigrp topology
IP-EIGRP Topology Table for AS 10/ID(10.1.5.1)
Codes: P - Passive, A - Active, U - Update, Q - Query, R - Reply,
r - Reply status
P 10.1.1.0/24, 1 successors, FD is 25625600
via Connected, Vlan1
P 10.1.2.0/24, 1 successors, FD is 2169856
via Connected, Serial0/0/0
P 10.1.3.0/24, 1 successors, FD is 2169856
via Connected, Serial0/0/1
P 10.1.4.0/24, 1 successors, FD is 2169856
via Connected, Serial0/1/0
P 10.1.5.0/24, 1 successors, FD is 28160
via Connected, FastEthernet0/0
P 172.16.10.0/24, 1 successors, FD is 28160
via 10.1.5.2 (28160/25600), FastEthernet0/0
P 192.168.10.0/24, 2 successors, FD is 2172416
via 10.1.3.2 (2172416/28160), Serial0/0/1
via 10.1.2.2 (2172416/28160), Serial0/0/0
P 192.168.20.0/24, 2 successors, FD is 2172416
via 10.1.3.2 (2172416/28160), Serial0/0/1
via 10.1.2.2 (2172416/28160), Serial0/0/0
P 192.168.30.0/24, 1 successors, FD is 2172416
via 10.1.4.2 (2172416/28160), Serial0/1/0
P 192.168.40.0/24, 1 successors, FD is 2172416
via 10.1.4.2 (2172416/28160), Serial0/1/0
the "P" preceding each entry is for PASSIVE
these routes are in a passive state, which is good
if they move to an ACTIVE state, it means the have lost their path in the network and looking for a replacement.
Each entry also shows the FEASIBLE DISTANCE, the next hop address, and the local egress interface
Corp#
show ip eigrp neighbors
IP-EIGRP neighbors for process 10
H Address Interface Hold Uptime SRTT RTO Q Seq
(sec) (ms) Cnt Num
0 10.1.5.2 Fa0/0 14 02:00:05 40 1000 0 19
1 10.1.3.2 Se0/0/1 13 01:59:59 40 1000 0 14
2 10.1.2.2 Se0/0/0 13 01:59:59 40 1000 0 13
3 10.1.4.2 Se0/1/0 12 01:59:57 40 1000 0 15
fields:
H - the order in which the neighbors were discovered
hold - how long the router will wait for a hello packet
uptime - how long the neigborship has been established
SRTT - smooth round trip timer - the time it takes for a round trip from this router, to neighbor, and back.
SRTT is used to determine how long to wait for a MULTICAST reply.
if a reply isnt received in time, the router switches to UNICASTS
RTO - Retransmission Time Out- is the time EIGRP waits before retransmitting a packet from the retransmission queue
Q - indicates wheter there are oustanding messages in the queue
Seq - indicates the sequence number of the last update from that neighbor. This is used to maintain syncrhonization and avoid duplicate
or out-of-sequence processing of messages
Corp#
show ip route eigrp
172.16.0.0/24 is subnetted, 1 subnets
D 172.16.10.0 [90/28160] via 10.1.5.2, 02:08:04, FastEthernet0/0
D 192.168.10.0/24 [90/2172416] via 10.1.3.2, 02:07:59, Serial0/0/1
[90/2172416] via 10.1.2.2, 02:07:59, Serial0/0/0
D 192.168.20.0/24 [90/2172416] via 10.1.3.2, 02:07:59, Serial0/0/1
[90/2172416] via 10.1.2.2, 02:07:59, Serial0/0/0
D 192.168.30.0/24 [90/2172416] via 10.1.4.2, 02:07:58, Serial0/1/0
D 192.168.40.0/24 [90/2172416] via 10.1.4.2, 02:07:58, Serial0/1/0
Corp#
show ip eigrp interfaces
IP-EIGRP interfaces for process 10
Xmit Queue Mean Pacing Time Multicast Pending
Interface Peers Un/Reliable SRTT Un/Reliable Flow Timer Routes
Vlan 0 0/0 1236 0/10 0 0
Fa0/0 1 0/0 1236 0/10 0 0
Se0/1/0 1 0/0 1236 0/10 0 0
Se0/0/1 1 0/0 1236 0/10 0 0
Se0/0/0 1 0/0 1236 0/10 0 0
Corp#
show ip protocols
Routing Protocol is "eigrp 10 "
Outgoing update filter list for all interfaces is not set
Incoming update filter list for all interfaces is not set
Default networks flagged in outgoing updates
Default networks accepted from incoming updates
Redistributing: eigrp 10
EIGRP-IPv4 Protocol for AS(10)
Metric weight K1=1, K2=0, K3=1, K4=0, K5=0 using K1 bandwidth and K2 delay by default
NSF-aware route hold timer is 240
Router-ID: 10.1.1.1
Topology : 0 (base)
Active Timer: 3 min
Distance: internal 90 external 170
Maximum path: 4
Maximum hopcount 100
Maximum metric variance 1
Automatic Summarization: disabled
Automatic address summarization:
Maximum path: 4
Routing for Networks:
10.0.0.0
Routing Information Sources:
Gateway Distance Last Update
10.1.5.2 90 0
10.1.3.2 90 8936
10.1.4.2 90 9511
10.1.2.2 90 9597
Distance: internal 90 external 170
Routing Protocol is "rip"
Sending updates every 30 seconds, next due in 13 seconds
Invalid after 180 seconds, hold down 180, flushed after 240
Outgoing update filter list for all interfaces is not set
Incoming update filter list for all interfaces is not set
Redistributing: rip
Default version control: send version 2, receive 2
Interface Send Recv Triggered RIP Key-chain
Vlan1 2 2
FastEthernet0/0 2 2
Serial0/0/1 2 2
Serial0/1/0 2 2
Serial0/0/0 2 2
Automatic network summarization is not in effect
Maximum path: 4
Routing for Networks:
10.0.0.0
Passive Interface(s):
Routing Information Sources:
Gateway Distance Last Update
10.1.5.2 120 00:00:05
10.1.3.2 120 00:00:12
10.1.2.2 120 00:00:12
10.1.4.2 120 00:00:17
Distance: (default is 120)
corp#
debug eigrp packet
break into two columns for readability
Observations:
There doesnt appear to be a pattern in the order each router is addressed, except that the TO's and FROM"s are grouped together
The TO messages dont show the destination IP, only the egress local interface
The FROM messages do show the remote IP, as well as the local ingress interface
Corp#
EIGRP: Received HELLO on FastEthernet0/0 nbr 10.1.5.2
AS 10, Flags 0x0, Seq 18/0 idbQ 0/0
hello from R3
Corp#
EIGRP: Received HELLO on Serial0/1/0 nbr 10.1.4.2
AS 10, Flags 0x0, Seq 16/0 idbQ 0/0
hello from R2
Corp#
EIGRP: Received HELLO on Serial0/0/0 nbr 10.1.2.2
AS 10, Flags 0x0, Seq 19/0 idbQ 0/0
hello from R1
------------------------------------------------------------
Corp#
EIGRP: Sending HELLO on Serial0/1/0
AS 10, Flags 0x0, Seq 21/0 idbQ 0/0 iidbQ un/rely 0/0
hello to R2
Corp#
EIGRP: Sending HELLO on FastEthernet0/0
AS 10, Flags 0x0, Seq 21/0 idbQ 0/0 iidbQ un/rely 0/0
hello to R3
Corp#
EIGRP: Sending HELLO on Serial0/0/1
AS 10, Flags 0x0, Seq 21/0 idbQ 0/0 iidbQ un/rely 0/0
hello to R1
Corp#
EIGRP: Sending HELLO on Serial0/0/0
AS 10, Flags 0x0, Seq 21/0 idbQ 0/0 iidbQ un/rely 0/0
hello to R1
Corp#
EIGRP: Sending HELLO on Vlan1
AS 10, Flags 0x0, Seq 21/0 idbQ 0/0 iidbQ un/rely 0/0
hello to switch card (not a router....)
------------------------------------------------------------
Corp#
EIGRP: Received HELLO on Serial0/0/1 nbr 10.1.3.2
AS 10, Flags 0x0, Seq 19/0 idbQ 0/0
hello from R1
Corp#
EIGRP: Received HELLO on FastEthernet0/0 nbr 10.1.5.2
AS 10, Flags 0x0, Seq 18/0 idbQ 0/0
hello from R3
Corp#
EIGRP: Received HELLO on Serial0/0/0 nbr 10.1.2.2
AS 10, Flags 0x0, Seq 19/0 idbQ 0/0
hello from R1
Corp#
EIGRP: Received HELLO on Serial0/1/0 nbr 10.1.4.2
AS 10, Flags 0x0, Seq 16/0 idbQ 0/0
hello from R2
------------------------------------------------------------
Corp#
EIGRP: Sending HELLO on Serial0/1/0
AS 10, Flags 0x0, Seq 21/0 idbQ 0/0 iidbQ un/rely 0/0
hello to R2... no neighbor IP?
Corp#
EIGRP: Sending HELLO on Serial0/0/0
AS 10, Flags 0x0, Seq 21/0 idbQ 0/0 iidbQ un/rely 0/0
hello to R1... no neighbor IP?
Corp#
EIGRP: Sending HELLO on FastEthernet0/0
AS 10, Flags 0x0, Seq 21/0 idbQ 0/0 iidbQ un/rely 0/0
hello to R3... no neighbor IP?
Corp#
EIGRP: Sending HELLO on Serial0/0/1
AS 10, Flags 0x0, Seq 21/0 idbQ 0/0 iidbQ un/rely 0/0
hello to R1
Corp#
EIGRP: Sending HELLO on Vlan1
AS 10, Flags 0x0, Seq 21/0 idbQ 0/0 iidbQ un/rely 0/0
hello to switch card (not a router)
------------------------------------------------------------
OUTPUT CONTINUES IN NEXT COLUMN
Corp#
EIGRP: Received HELLO on Serial0/0/1 nbr 10.1.3.2
AS 10, Flags 0x0, Seq 19/0 idbQ 0/0
hello from R1
Corp#
EIGRP: Received HELLO on FastEthernet0/0 nbr 10.1.5.2
AS 10, Flags 0x0, Seq 18/0 idbQ 0/0
hello from R3
Corp#
EIGRP: Received HELLO on Serial0/0/0 nbr 10.1.2.2
AS 10, Flags 0x0, Seq 19/0 idbQ 0/0
hello from R1
Corp#
EIGRP: Received HELLO on Serial0/1/0 nbr 10.1.4.2
AS 10, Flags 0x0, Seq 16/0 idbQ 0/0
hello from R2
------------------------------------------------------------
Corp#
EIGRP: Sending HELLO on Serial0/1/0
AS 10, Flags 0x0, Seq 21/0 idbQ 0/0 iidbQ un/rely 0/0
hello to R2
Corp#
EIGRP: Sending HELLO on Serial0/0/0
AS 10, Flags 0x0, Seq 21/0 idbQ 0/0 iidbQ un/rely 0/0
hello to R1
Corp#
EIGRP: Sending HELLO on Vlan1
AS 10, Flags 0x0, Seq 21/0 idbQ 0/0 iidbQ un/rely 0/0
hello to Corp switchcard
Corp#
EIGRP: Sending HELLO on Serial0/0/1
AS 10, Flags 0x0, Seq 21/0 idbQ 0/0 iidbQ un/rely 0/0
hello to R1
Corp#
EIGRP: Sending HELLO on FastEthernet0/0
AS 10, Flags 0x0, Seq 21/0 idbQ 0/0 iidbQ un/rely 0/0
hello to R3... no neighbor IP?
------------------------------------------------------------
Corp#
EIGRP: Received HELLO on Serial0/0/1 nbr 10.1.3.2
AS 10, Flags 0x0, Seq 19/0 idbQ 0/0
hello from R1
Corp#
EIGRP: Received HELLO on FastEthernet0/0 nbr 10.1.5.2
AS 10, Flags 0x0, Seq 18/0 idbQ 0/0
hello from R3
Corp#
EIGRP: Received HELLO on Serial0/1/0 nbr 10.1.4.2
AS 10, Flags 0x0, Seq 16/0 idbQ 0/0
hello from R2
Corp#
EIGRP: Received HELLO on Serial0/0/0 nbr 10.1.2.2
AS 10, Flags 0x0, Seq 19/0 idbQ 0/0
hello from R1
------------------------------------------------------------
Corp#
EIGRP: Sending HELLO on Serial0/1/0
AS 10, Flags 0x0, Seq 21/0 idbQ 0/0 iidbQ un/rely 0/0
hello to R2
Corp#
EIGRP: Sending HELLO on Vlan1
AS 10, Flags 0x0, Seq 21/0 idbQ 0/0 iidbQ un/rely 0/0
hello to Corp switchcard
EIGRP: Sending HELLO on Serial0/0/0
AS 10, Flags 0x0, Seq 21/0 idbQ 0/0 iidbQ un/rely 0/0
hello to R1
EIGRP: Sending HELLO on Serial0/0/1
AS 10, Flags 0x0, Seq 21/0 idbQ 0/0 iidbQ un/rely 0/0
hello to R1
Corp#
EIGRP: Sending HELLO on FastEthernet0/0
AS 10, Flags 0x0, Seq 21/0 idbQ 0/0 iidbQ un/rely 0/0
hello to R3
------------------------------------------------------------
Now some videos. To reinforce EIGRP concepts, and lead into OSPF
OSPF - OPEN SHORTEST PATH FIRST
Before enabling OSPF, we'll turn off RIP and EIGRP on all four routers.
Device(config)#
no router eigrp 10
Device(config)#
no router rip
The OSPF configs for the local egress ip address
Corp(config)#
router ospf 132
Corp(config)#
network 10.1.0.0 0.0.255.255 area 0
R1(config)#
router ospf 1
R1(config)#
network 10.1.0.0 0.0.255.255 area 0
R1(config)#
network 192.168.0.0 0.0.255.255 area 0
R2(config)#
router ospf 45678
R2(config)#
network 10.0.0.0 0.0.0.255 area 0
R2(config)#
network 192.168.30.1 0.0.0.0 area 0
R2(config)#
network 192.168.40.1 0.0.0.0 area 0
all 32 bits of the mask are specified for the 192 entries;
these are not network id's, they are HOST id's of the specific interfaces, which are EGRESS interfaces on the router we are configuring
R3(config)#
router ospf 1
R2(config)#
network 10.1.5.2 0.0.0.255 area 0
R2(config)#
network 172.16.10.0 0.0.0.255 area 0
Wildcard Masks
these notes are not intended to be a precise explanation of wlidcard masking, but rather a look into my thought process as I am learning the concept.
resources:
traceroute blog examples
routerjockey blog examples
subnetonline wildcard calculator
Ch 9 Exam Essentials
1. Know EIGRP features
classless (like RipV2 and OSPF)
distance vector
supports IP, IPX, appleTalk, IPV6
supports summaries and discontiguous networks
uses the Diffusing Update Algorithm (DUAL) to maintain route information
uses RTP to communicate with other EIGRP routers
uses the concept of an autonomous system to describe the set of contiguous routers that run the same routing protocol and share routing information
considered CLASSLESS- includes the subnet mask in its route updates
sends traditional distance-vector updates containing info about networks plus the cost of reaching them from the perspective of the advertising router
but not strictly distance-vector. Has link-state characteristics: synchronizes routing tables between neighbors at startup and then sends specific updates only when topology changes.
max hop count of 255 (default is 100)
but hop count is NOT a metric, like in RIP. Hop count is how many routers an EIGRP route update can traverse before being discarded. This limits the size of the AS.
2. Know how to configure EIGRP
the router eigrp [as] command turns EIGRP routing on in the router. Unlike RIPv1, EIGRP uses classless routing. BUT you can still configure as classful.
R1(config)#
router eigrp 10
enters router config mode
R1(config-router)#
network 10.0.0.0
on this router, interfaces that fall within 10.0.0.0 will advertise EIGRP info
3. Know how to verify EIGRP operation
Corp#
show ip
protocols
Corp#
show ip
route
Corp#
show ip
route eigrp
Corp#
show ip
eigrp neighbors
Corp#
show ip
eigrp topology
Corp#
show ip
eigrp interfaces
Corp#
show ip
protocols
info about all active routing protocols
Routing Protocol is "eigrp 10 "
Outgoing update filter list for all interfaces is not set
Incoming update filter list for all interfaces is not set
Default networks flagged in outgoing updates
Default networks accepted from incoming updates
Redistributing: eigrp 10
EIGRP-IPv4 Protocol for AS(10)
Metric weight K1=1, K2=0, K3=1, K4=0, K5=0
NSF-aware route hold timer is 240
Router-ID: 10.1.1.1
Topology : 0 (base)
Active Timer: 3 min
Distance: internal 90 external 170
Maximum path: 4
Maximum hopcount 100
Maximum metric variance 1
Automatic Summarization: disabled
Automatic address summarization:
Maximum path: 4
Routing for Networks:
10.0.0.0
Routing Information Sources:
Gateway Distance Last Update
10.1.2.2 90 200105
10.1.3.2 90 200113
10.1.4.2 90 254351
10.1.5.2 90 303742
Distance: internal 90 external 170
Corp#
show ip
protocols
(continued)
Routing Protocol is "rip"
Sending updates every 30 seconds, next due in 6 seconds
Invalid after 180 seconds, hold down 180, flushed after 240
Outgoing update filter list for all interfaces is not set
Incoming update filter list for all interfaces is not set
Redistributing: rip
Default version control: send version 2, receive 2
Interface Send Recv Triggered RIP Key-chain
Vlan1 2 2
FastEthernet0/0 2 2
Serial0/1/0 2 2
Serial0/0/1 2 2
Serial0/0/0 2 2
Automatic network summarization is not in effect
Maximum path: 4
Routing for Networks:
10.0.0.0
Passive Interface(s):
Routing Information Sources:
Gateway Distance Last Update
10.1.5.2 120 00:00:15
10.1.3.2 120 00:00:01
10.1.2.2 120 00:00:01
10.1.4.2 120 00:00:17
Distance: (default is 120)
Corp#
show ip
route
entire routing table
Codes: L - local, C - connected, S - static, R - RIP, M - mobile, B - BGP
D - EIGRP, EX - EIGRP external, O - OSPF, IA - OSPF inter area
N1 - OSPF NSSA external type 1, N2 - OSPF NSSA external type 2
E1 - OSPF external type 1, E2 - OSPF external type 2, E - EGP
i - IS-IS, L1 - IS-IS level-1, L2 - IS-IS level-2, ia - IS-IS inter area
* - candidate default, U - per-user static route, o - ODR
P - periodic downloaded static route
Gateway of last resort is not set
10.0.0.0/8 is variably subnetted, 10 subnets, 2 masks
C 10.1.1.0/24 is directly connected, Vlan1
L 10.1.1.1/32 is directly connected, Vlan1
C 10.1.2.0/24 is directly connected, Serial0/0/0
L 10.1.2.1/32 is directly connected, Serial0/0/0
C 10.1.3.0/24 is directly connected, Serial0/0/1
L 10.1.3.1/32 is directly connected, Serial0/0/1
C 10.1.4.0/24 is directly connected, Serial0/1/0
L 10.1.4.1/32 is directly connected, Serial0/1/0
C 10.1.5.0/24 is directly connected, FastEthernet0/0
L 10.1.5.1/32 is directly connected, FastEthernet0/0
172.16.0.0/16 is variably subnetted, 2 subnets, 2 masks
R 172.16.0.0/16 [120/1] via 10.1.5.2, 00:00:14, FastEthernet0/0
D 172.16.10.0/24 [90/28160] via 10.1.5.2, 00:07:23, FastEthernet0/0
D 192.168.10.0/24 [90/2172416] via 10.1.3.2, 00:09:13, Serial0/0/1
[90/2172416] via 10.1.2.2, 00:09:13, Serial0/0/0
D 192.168.20.0/24 [90/2172416] via 10.1.3.2, 00:09:13, Serial0/0/1
[90/2172416] via 10.1.2.2, 00:09:13, Serial0/0/0
D 192.168.30.0/24 [90/2172416] via 10.1.4.2, 00:08:59, Serial0/1/0
D 192.168.40.0/24 [90/2172416] via 10.1.4.2, 00:08:59, Serial0/1/0
Shows the entire routing table
Corp#
show ip
eigrp toplogy
all nets the Corp router can see, including on the other side of other routers
IP-EIGRP Topology Table for AS 10/ID(10.1.5.1)
Codes: P - Passive, A - Active, U - Update, Q - Query, R - Reply,
r - Reply status
directly connected via local egress interface
P 10.1.1.0/24, 1 successors, FD is 25625600
via Connected, Vlan1
P 10.1.2.0/24, 1 successors, FD is 2169856
via Connected, Serial0/0/0
P 10.1.3.0/24, 1 successors, FD is 2169856
via Connected, Serial0/0/1
P 10.1.4.0/24, 1 successors, FD is 2169856
via Connected, Serial0/1/0
P 10.1.5.0/24, 1 successors, FD is 28160
via Connected, FastEthernet0/0
remotely connected via remote ingress ip address
P 172.16.10.0/24, 1 successors, FD is 28160
via 10.1.5.2 (28160/25600), FastEthernet0/0
P 192.168.10.0/24, 2 successors, FD is 2172416
via 10.1.3.2 (2172416/28160), Serial0/0/1
via 10.1.2.2 (2172416/28160), Serial0/0/0
P 192.168.20.0/24, 2 successors, FD is 2172416
via 10.1.3.2 (2172416/28160), Serial0/0/1
via 10.1.2.2 (2172416/28160), Serial0/0/0
P 192.168.30.0/24, 1 successors, FD is 2172416
via 10.1.4.2 (2172416/28160), Serial0/1/0
P 192.168.40.0/24, 1 successors, FD is 2172416
via 10.1.4.2 (2172416/28160), Serial0/1/0
Corp#
show ip
eigrp interfaces
local interfaces on Corp, with peer data, 5 total, including VLAN1 (0 peers, no router on this network)
IP-EIGRP interfaces for process 10
Xmit Queue Mean Pacing Time Multicast Pending
Interface Peers Un/Reliable SRTT Un/Reliable Flow Timer Routes
Vlan 0 0/0 1236 0/10 0 0
Fa0/0 1 0/0 1236 0/10 0 0
Se0/0/1 1 0/0 1236 0/10 0 0
Se0/1/0 1 0/0 1236 0/10 0 0
Se0/0/0 1 0/0 1236 0/10 0 0
Corp#
show ip
eigrp neighbors
remote interfaces on the 4 neighboring routers
IP-EIGRP neighbors for process 10
H Address Interface Hold Uptime SRTT RTO Q Seq
(sec) (ms) Cnt Num
0 10.1.2.2 Se0/0/0 14 00:54:33 40 1000 0 58
1 10.1.3.2 Se0/0/1 10 00:54:33 40 1000 0 57
2 10.1.4.2 Se0/1/0 14 00:53:38 40 1000 0 51
3 10.1.5.2 Fa0/0 11 00:52:49 40 1000 0 33
4. Compare OSPF and RIPv1
RIPv1 is distance-vector and supports only classful routing. No VLSM
OSPF is link-state and supports VLSM and classless routing
5. Know how OSPF routers become neighboars and/or adjacent
they become neighbors when they see eachother's hello packets.
area id must match, links must be on the same subnet, hello/dead timers must be the same.
OSPF only shares routes with neigbors who have also established adjacencies. NOT ALL NEIGHBORS become adjacent.
When an OSPF router first receives a hello packet, it verifies that the data in some fields matches its own locally configured information.
Should any of the checked data be different, the hello packet is discarded and not processed. The data fields verified are the Area ID,
Authentication, Network Mask (on broadcast networks), Hello Interval, Router Dead Interval, and Options fields. If this information doesn’t match,
then neighborship is stuck in the down stage.
packetpushers.net
6. Be able to configure single-area OSPF
two commands:
router ospf [process id]
network x.x.x.x y.y.y.y area z
7. Be able to verify the operation of OSPF
Corp#
show ip
protocols
Corp#
show ip
route
Corp#
show ip
ospf
Corp#
show ip
ospf database
Corp#
show ip
ospf interface
Corp#
show ip
ospf neighbor
IOS 15.1
Corp#
show ip
protocols
Routing Protocol is "ospf 132"
Outgoing update filter list for all interfaces is not set
Incoming update filter list for all interfaces is not set
Router ID 10.1.5.1
Number of areas in this router is 1. 1 normal 0 stub 0 nssa
Maximum path: 4
Routing for Networks:
10.1.0.0 0.0.255.255 area 0
Routing Information Sources:
Gateway Distance Last Update
10.1.5.1 110 00:08:51
172.16.10.1 110 00:08:51
192.168.20.1 110 00:12:53
192.168.40.1 110 00:09:35
Distance: (default is 110)
IOS 15.1
Corp#
show ip
route
10.0.0.0/8 is variably subnetted, 10 subnets, 2 masks
C 10.1.1.0/24 is directly connected, Vlan1
L 10.1.1.1/32 is directly connected, Vlan1
C 10.1.2.0/24 is directly connected, Serial0/0/0
L 10.1.2.1/32 is directly connected, Serial0/0/0
C 10.1.3.0/24 is directly connected, Serial0/0/1
L 10.1.3.1/32 is directly connected, Serial0/0/1
C 10.1.4.0/24 is directly connected, Serial0/1/0
L 10.1.4.1/32 is directly connected, Serial0/1/0
C 10.1.5.0/24 is directly connected, FastEthernet0/0
L 10.1.5.1/32 is directly connected, FastEthernet0/0
172.16.0.0/24 is subnetted, 1 subnets
O 172.16.10.0/24 [110/10] via 10.1.5.2, 00:09:09, FastEthernet0/0
O 192.168.10.0/24 [110/65] via 10.1.2.2, 00:13:11, Serial0/0/0
O 192.168.20.0/24 [110/65] via 10.1.2.2, 00:13:01, Serial0/0/0
O 192.168.30.0/24 [110/65] via 10.1.4.2, 00:09:54, Serial0/1/0
O 192.168.40.0/24 [110/65] via 10.1.4.2, 00:09:54, Serial0/1/0
IOS 15.1
Corp#
show ip
ospf
Routing Process "ospf 132" with ID 10.1.5.1
Supports only single TOS(TOS0) routes
Supports opaque LSA
SPF schedule delay 5 secs, Hold time between two SPFs 10 secs
Minimum LSA interval 5 secs. Minimum LSA arrival 1 secs
Number of external LSA 0. Checksum Sum 0x000000
Number of opaque AS LSA 0. Checksum Sum 0x000000
Number of DCbitless external and opaque AS LSA 0
Number of DoNotAge external and opaque AS LSA 0
Number of areas in this router is 1. 1 normal 0 stub 0 nssa
External flood list length 0
Area BACKBONE(0)
Number of interfaces in this area is 5
Area has no authentication
SPF algorithm executed 7 times
Area ranges are
Number of LSA 5. Checksum Sum 0x034486
Number of opaque link LSA 0. Checksum Sum 0x000000
Number of DCbitless LSA 0
Number of indication LSA 0
Number of DoNotAge LSA 0
Flood list length 0
IOS 15.1
Corp#
show ip
ospf database
OSPF Router with ID (10.1.5.1) (Process ID 132)
Router Link States (Area 0)
Link ID ADV Router Age Seq# Checksum Link count
192.168.20.1 192.168.20.1 854 0x80000006 0x00ae08 6
192.168.40.1 192.168.40.1 656 0x80000004 0x006bc6 4
10.1.5.1 10.1.5.1 612 0x8000000f 0x00ab77 8
172.16.10.1 172.16.10.1 612 0x80000003 0x00b30d 2
Net Link States (Area 0)
Link ID ADV Router Age Seq# Checksum
10.1.5.1 10.1.5.1 612 0x80000001 0x00cc34
ADV Router aka RID/Router ID, the highest IP address on the router
we are seeing three connected routers + our own router (Corp at 10.1.5.1)
IOS 15.1
Corp#
show ip
ospf interface
Vlan1 is up, line protocol is up
Internet address is 10.1.1.1/24, Area 0
Process ID 132, Router ID 10.1.5.1, Network Type BROADCAST, Cost: 1
Transmit Delay is 1 sec, State DR, Priority 1
Designated Router (ID) 10.1.5.1, Interface address 10.1.1.1
No backup designated router on this network
Timer intervals configured, Hello 10, Dead 40, Wait 40, Retransmit 5
Hello due in 00:00:08
Index 1/1, flood queue length 0
Next 0x0(0)/0x0(0)
Last flood scan length is 1, maximum is 1
Last flood scan time is 0 msec, maximum is 0 msec
Neighbor Count is 0, Adjacent neighbor count is 0
Suppress hello for 0 neighbor(s)
FastEthernet0/0 is up, line protocol is up
Internet address is 10.1.5.1/24, Area 0
Process ID 132, Router ID 10.1.5.1, Network Type BROADCAST, Cost: 1
Transmit Delay is 1 sec, State DR, Priority 1
Designated Router (ID) 10.1.5.1, Interface address 10.1.5.1
Backup Designated Router (ID) 172.16.10.1, Interface address 10.1.5.2
Timer intervals configured, Hello 10, Dead 40, Wait 40, Retransmit 5
Hello due in 00:00:07
Index 2/2, flood queue length 0
Next 0x0(0)/0x0(0)
Last flood scan length is 1, maximum is 1
Last flood scan time is 0 msec, maximum is 0 msec
Neighbor Count is 1, Adjacent neighbor count is 1
Adjacent with neighbor 172.16.10.1 (Backup Designated Router)
Suppress hello for 0 neighbor(s)
Serial0/0/1 is up, line protocol is up
Internet address is 10.1.3.1/24, Area 0
Process ID 132, Router ID 10.1.5.1, Network Type POINT-TO-POINT, Cost: 64
Transmit Delay is 1 sec, State POINT-TO-POINT,
Timer intervals configured, Hello 10, Dead 40, Wait 40, Retransmit 5
Hello due in 00:00:07
Index 3/3, flood queue length 0
Next 0x0(0)/0x0(0)
Last flood scan length is 1, maximum is 1
Last flood scan time is 0 msec, maximum is 0 msec
Neighbor Count is 1 , Adjacent neighbor count is 1
Adjacent with neighbor 192.168.20.1
Suppress hello for 0 neighbor(s)
Serial0/1/0 is up, line protocol is up
Internet address is 10.1.4.1/24, Area 0
Process ID 132, Router ID 10.1.5.1, Network Type POINT-TO-POINT, Cost: 64
Transmit Delay is 1 sec, State POINT-TO-POINT,
Timer intervals configured, Hello 10, Dead 40, Wait 40, Retransmit 5
Hello due in 00:00:07
Index 4/4, flood queue length 0
Next 0x0(0)/0x0(0)
Last flood scan length is 1, maximum is 1
Last flood scan time is 0 msec, maximum is 0 msec
Neighbor Count is 1 , Adjacent neighbor count is 1
Adjacent with neighbor 192.168.40.1
Suppress hello for 0 neighbor(s)
Serial0/0/0 is up, line protocol is up
Internet address is 10.1.2.1/24, Area 0
Process ID 132, Router ID 10.1.5.1, Network Type POINT-TO-POINT, Cost: 64
Transmit Delay is 1 sec, State POINT-TO-POINT,
Timer intervals configured, Hello 10, Dead 40, Wait 40, Retransmit 5
Hello due in 00:00:07
Index 5/5, flood queue length 0
Next 0x0(0)/0x0(0)
Last flood scan length is 1, maximum is 1
Last flood scan time is 0 msec, maximum is 0 msec
Neighbor Count is 1 , Adjacent neighbor count is 1
Adjacent with neighbor 192.168.20.1
Suppress hello for 0 neighbor(s)
IOS 15.1
Corp#
show ip
ospf neighbor
Neighbor ID Pri State Dead Time Address Interface
192.168.20.1 0 FULL/ - 00:00:31 10.1.3.2 Serial0/0/1
192.168.40.1 0 FULL/ - 00:00:33 10.1.4.2 Serial0/1/0
192.168.20.1 0 FULL/ - 00:00:31 10.1.2.2 Serial0/0/0
172.16.10.1 1 FULL/BDR 00:00:32 10.1.5.2 FastEthernet0/0
Flashcards
Chapter 9 Written Lab 9.0
1. What four routed protocols are supported by EIGRP?
IPX, IPv4, IPv6, AppleTalk
2. When is redistribution required for EIGRP?
when there are multiple autonomous systems
redistribution is required when more than one EIGRP session or process is running and they are identified with different ASNs.
redistribution shares toplogy information between EIGRP sessions
3. What command would be used to enable EIGRP with an autonmous system number of 300?
router eigrp 300
4. What command will tell EIGRP that it is connected to network 172.10.0.0?
network 172.10.0.0
5. What type of EIGRP interface will neither send nor receive Hello packets?
passive-interface s0/0
6. Write the command that will enable OSPF process 101 on a router
router ospf 101
7. Write the command that will display details of all OSFP routing processes enabled on a router
show ip ospf
8. Write the command that will display interface-specific OSPF information
show ip ospf interface
9. Write the command that will display all OSPF neighbors
show ip ospf neighbor
10. Write the command that will display all different OSPF route types that are currently known by the router
show ip route ospf
Chapter 9 Hands-On Labs
Build the network and configure interfaces
LabA(config)#
int f0/0
LabA(config-if)#
ip addr 172.16.10.1 255.255.255.0
LabA(config-if)#
no shut
LabB(config)#
int f0/0
LabB(config-if)#
ip addr 172.16.10.2 255.255.255.0
LabB(config-if)#
no shut
LabB(config-if)#
int s0/0/0
LabB(config-if)#
ip addr 172.16.20.1 255.255.255.0
LabB(config-if)#
no shut
LabC(config)#
int f0/0
LabC(config-if)#
ip addr 172.16.30.1 255.255.255.0
LabC(config-if)#
no shut
LabC(config-if)#
int s0/0/0
LabC(config-if)#
ip addr 172.16.20.2 255.255.255.0
LabC(config-if)#
no shut
LabC(config-if)#
int s0/0/1
LabC(config-if)#
ip addr 172.16.40.1 255.255.255.0
LabC(config-if)#
no shut
LabD(config)#
int s0/0/0
LabD(config-if)#
ip addr 172.16.40.2 255.255.255.0
LabD(config-if)#
no shut
LabD(config-if)#
int f0/0
LabD(config-if)#
ip addr 172.16.50.1 255.255.255.0
LabD(config-if)#
no shut
9.1 - Configure and Verfiy EIGRP
configure EIGRP on all 4 routers and observe results
LabA
LabA(config)#
router eigrp 100
LabA(config-router)#
net 172.16.0.0
[no output]
LabA#
show ip eigrp neighbors
IP-EIGRP neighbors for process 100
LabA#
show ip eigrp topology
IP-EIGRP Topology Table for AS 100/ID(172.16.10.1)
Codes: P - Passive, A - Active, U - Update, Q - Query, R - Reply,
r - Reply status
P 172.16.10.0/24, 1 successors, FD is 28160
via Connected, FastEthernet0/0
LabA#
show ip eigrp interfaces
IP-EIGRP interfaces for process 100
Xmit Queue Mean Pacing Time Multicast Pending
Interface Peers Un/Reliable SRTT Un/Reliable Flow Timer Routes
Fa0/0 0 0/0 1236 0/10 0 0
no neighbors at this point since EIGRP is only active on this router. One successor AKA route, which is the connection out of this router.
But note that we have no information about what's on the other side of that link
LabB
LabB(config)#
router eigrp 100
LabB(config-router)#
net 172.16.0.0
%DUAL-5-NBRCHANGE: IP-EIGRP 100:
Neighbor 172.16.10.1 (FastEthernet0/0) is up: new adjacency
LabB#
show ip eigrp neighbors
IP-EIGRP neighbors for process 100
H Address Interface Hold Uptime SRTT RTO Q Seq
(sec) (ms) Cnt Num
0 172.16.10.1 Fa0/0 12 00:00:14 40 1000 0 1
LabB#
show ip eigrp topology
IP-EIGRP Topology Table for AS 100/ID(172.16.20.1)
Codes: P - Passive, A - Active, U - Update, Q - Query, R - Reply,
r - Reply status
P 172.16.10.0/24, 1 successors, FD is 28160
via Connected, FastEthernet0/0
P 172.16.20.0/24, 1 successors, FD is 2169856
via Connected, Serial0/0/0
LabB#
show ip eigrp interfaces
IP-EIGRP interfaces for process 100
Xmit Queue Mean Pacing Time Multicast Pending
Interface Peers Un/Reliable SRTT Un/Reliable Flow Timer Routes
Fa0/0 1 0/0 1236 0/10 0 0
Se0/0/0 0 0/0 1236 0/10 0 0
We can see a neighbor at .1
We now have two paths out of this router. Left to neighbor. Exit at right is available as successor(route), but again we have no info about
what is on the other side, since that router has no EIGRP yet (s0/0/0 has no peers, but is an EIGRP interface)
LabC
LabC(config)#
router eigrp 100
LabC(config-router)#
net 172.16.0.0
%DUAL-5-NBRCHANGE: IP-EIGRP 100:
Neighbor 172.16.20.1 (Serial0/0/0) is up: new adjacency
LabC#
show ip eigrp neighbors
IP-EIGRP neighbors for process 100
H Address Interface Hold Uptime SRTT RTO Q Seq
(sec) (ms) Cnt Num
0 172.16.20.1 Se0/0/0 12 00:00:25 40 1000 0 8
LabC#
show ip eigrp toplogy
IP-EIGRP Topology Table for AS 100/ID(172.16.40.1)
Codes: P - Passive, A - Active, U - Update, Q - Query, R - Reply,
r - Reply status
P 172.16.10.0/24, 1 successors, FD is 2172416
via 172.16.20.1 (2172416/28160), Serial0/0/0
P 172.16.20.0/24, 1 successors, FD is 2169856
via Connected, Serial0/0/0
P 172.16.30.0/24, 1 successors, FD is 28160
via Connected, FastEthernet0/0
P 172.16.40.0/24, 1 successors, FD is 2169856
via Connected, Serial0/0/1
LabC#
show ip eigrp interfaces
IP-EIGRP interfaces for process 100
Xmit Queue Mean Pacing Time Multicast Pending
Interface Peers Un/Reliable SRTT Un/Reliable Flow Timer Routes
Fa0/0 0 0/0 1236 0/10 0 0
Se0/0/0 1 0/0 1236 0/10 0 0
Se0/0/1 0 0/0 1236 0/10 0 0
.1 router B interface is now a neighbor.
LabC topology shows the 3 direct connected networks AND the network on the other side of LabB since LabB is our EIGRP neighbor
3 eigrp interfaces:
Fa0/0 is ours at LabC- no peers bc there is no eigrp router on the other end
s0/0/0 is our interface out left to LabB which is an EIGRP peer
s0/0/1 is our interface out right which does not see an EIGRP peer but does put that net 172.16.40.0 in our topology
LabD
LabD(config)#
router eigrp 100
LabD(config-router)#
net 172.16.0.0
%DUAL-5-NBRCHANGE: IP-EIGRP 100:
Neighbor 172.16.40.1 (Serial0/0/0) is up: new adjacency
LabD#
show ip eigrp neighbors
IP-EIGRP neighbors for process 100
H Address Interface Hold Uptime SRTT RTO Q Seq
(sec) (ms) Cnt Num
0 172.16.40.1 Se0/0/0 11 00:00:14 40 1000 0 6
LabD#
show ip eigrp topology
IP-EIGRP Topology Table for AS 100/ID(172.16.50.1)
Codes: P - Passive, A - Active, U - Update, Q - Query, R - Reply,
r - Reply status
P 172.16.10.0/24, 1 successors, FD is 2684416
via 172.16.40.1 (2684416/2172416), Serial0/0/0
P 172.16.20.0/24, 1 successors, FD is 2681856
via 172.16.40.1 (2681856/2169856), Serial0/0/0
P 172.16.30.0/24, 1 successors, FD is 2172416
via 172.16.40.1 (2172416/28160), Serial0/0/0
P 172.16.40.0/24, 1 successors, FD is 2169856
via Connected, Serial0/0/0
P 172.16.50.0/24, 1 successors, FD is 28160
via Connected, FastEthernet0/0
LabD#
show ip eigrp interfaces
IP-EIGRP interfaces for process 100
Xmit Queue Mean Pacing Time Multicast Pending
Interface Peers Un/Reliable SRTT Un/Reliable Flow Timer Routes
Fa0/0 0 0/0 1236 0/10 0 0
Se0/0/0 1 0/0 1236 0/10 0 0
LabC to our left is now a neighbor at 172.16.40.1
toplogy shows a route out to the right (no router on that end)
a route to the left to LabC .40.0
the .10.0, .20.0, and .30.0 networks via info from LabC
2 eigrp interfaces-
fa0/0 out to the right
s0/0/0 out left to LabC
Time to remove EIGRP from all four routers to prepare for the OSPF lab next,
since EIGRP has a lower AD than OSPF
LabA(config)#
no router eigrp 100
LabB(config)#
no router eigrp 100
LabC(config)#
no router eigrp 100
LabD(config)#
no router eigrp 100
9.2 - Enabling the OSPF Process
9.3 - Configuring OSPF Interfaces
9.4 - Verifying OSPF Operation
LabA
LabA(config)#
router ospf 100
LabA(config-router)#
net 172.16.10.1 0.0.0.0 area 0
[no output]
LabA#
show ip ospf neighbor
[no output]
LabA#
show ip ospf database
OSPF Router with ID (172.16.10.1) (Process ID 100)
Router Link States (Area 0)
Link ID ADV Router Age Seq# Checksum Link count
172.16.10.1 172.16.10.1 44 0x80000001 0x00b24b 1
LabA#
show ip ospf interface
FastEthernet0/0 is up, line protocol is up
Internet address is 172.16.10.1/24, Area 0
Process ID 100, Router ID 172.16.10.1, Network Type BROADCAST, Cost: 1
Transmit Delay is 1 sec, State DR, Priority 1
Designated Router (ID) 172.16.10.1, Interface address 172.16.10.1
No backup designated router on this network
Timer intervals configured, Hello 10, Dead 40, Wait 40, Retransmit 5
Hello due in 00:00:08
Index 1/1, flood queue length 0
Next 0x0(0)/0x0(0)
Last flood scan length is 1, maximum is 1
Last flood scan time is 0 msec, maximum is 0 msec
Neighbor Count is 0, Adjacent neighbor count is 0
Suppress hello for 0 neighbor(s)
we're including this router's interface 172.16.10.1 in our ospf area 0
fa0/0 now registers as an ospf interface
the ospf database includes data about this link only.... LabA is counting itself(10.1) as ADVERTISTING router?
the designated router is .1 LabA
LabB
LabB(config)#
router ospf 101
LabB(config-router)#
net 172.16.10.2 0.0.0.0 area 0
LabB(config-router)#
net 172.16.20.1 0.0.0.0 area 0
01:26:36: %OSPF-5-ADJCHG: Process 101, Nbr 172.16.10.1
on FastEthernet0/0 from LOADING to FULL, Loading Done
LabB#
show ip ospf neighbor
Neighbor ID Pri State Dead Time Address Interface
172.16.10.1 1 FULL/DR 00:00:33 172.16.10.1
LabB#
show ip ospf database
OSPF Router with ID (172.16.20.1) (Process ID 101)
Router Link States (Area 0)
Link ID ADV Router Age Seq# Checksum Link count
172.16.10.1 172.16.10.1 145 0x80000002 0x0067cd 1
172.16.20.1 172.16.20.1 32 0x80000003 0x006e8f 2
Net Link States (Area 0)
Link ID ADV Router Age Seq# Checksum
172.16.10.1 172.16.10.1 145 0x80000001 0x00953d
LabB#
show ip ospf interface
FastEthernet0/0 is up, line protocol is up
Internet address is 172.16.10.2/24, Area 0
Process ID 101, Router ID 172.16.20.1, Network Type BROADCAST, Cost: 1
Transmit Delay is 1 sec, State BDR, Priority 1
Designated Router (ID) 172.16.10.1, Interface address 172.16.10.1
Backup Designated Router (ID) 172.16.20.1, Interface address 172.16.10.2
Timer intervals configured, Hello 10, Dead 40, Wait 40, Retransmit 5
Hello due in 00:00:03
Index 1/1, flood queue length 0
Next 0x0(0)/0x0(0)
Last flood scan length is 1, maximum is 1
Last flood scan time is 0 msec, maximum is 0 msec
Neighbor Count is 1, Adjacent neighbor count is 1
Adjacent with neighbor 172.16.10.1 (Designated Router)
Suppress hello for 0 neighbor(s)
Serial0/0/0 is up, line protocol is up
Internet address is 172.16.20.1/24, Area 0
Process ID 101, Router ID 172.16.20.1, Network Type POINT-TO-POINT, Cost: 64
Transmit Delay is 1 sec, State POINT-TO-POINT,
Timer intervals configured, Hello 10, Dead 40, Wait 40, Retransmit 5
Hello due in 00:00:04
Index 2/2, flood queue length 0
Next 0x0(0)/0x0(0)
Last flood scan length is 1, maximum is 1
Last flood scan time is 0 msec, maximum is 0 msec
Suppress hello for 0 neighbor(s)
We've include the two interfaces on this router in the OSPF area
and can now see Router A's interface 10.1 to the left as a neighbor in the area
the "OSPF Database" now shows two links 20.1(local) and 10.1(neighbor) as 'router link states'.
"ADV Router" means advertising router for the two links. The link address is used as the advertising router.
database shows "Net Link States" category with one entry- 172.16.10.1 which is the address of neighbor router to our left
we have two local OSPF interfaces- f0/0 and s0/0/0
LabC
LabC(config)#
router ospf 102
LabC(config-router)#
net 172.16.20.2 0.0.0.0 area 0
LabC(config-router)#
net 172.16.30.1 0.0.0.0 area 0
LabC(config-router)#
net 172.16.40.1 0.0.0.0 area 0
01:33:54: %OSPF-5-ADJCHG: Process 102, Nbr 172.16.20.1
on Serial0/0/0 from LOADING to FULL, Loading Done
LabC#
show ip ospf neighbor
Neighbor ID Pri State Dead Time Address Interface
172.16.20.1 0 FULL/ - 00:00:30 172.16.20.1 Serial0/0/0
LabC#
show ip ospf database
OSPF Router with ID (172.16.40.1) (Process ID 102)
Router Link States (Area 0)
Link ID ADV Router Age Seq# Checksum Link count
172.16.10.1 172.16.10.1 542 0x80000002 0x0067cd 1
172.16.20.1 172.16.20.1 90 0x80000004 0x00a551 3
172.16.40.1 172.16.40.1 37 0x80000004 0x00e47c 4
Net Link States (Area 0)
Link ID ADV Router Age Seq# Checksum
172.16.10.1 172.16.10.1 542 0x80000001 0x00953d
LabC#
show ip ospf interface
Serial0/0/0 is up, line protocol is up
Internet address is 172.16.20.2/24, Area 0
Process ID 102, Router ID 172.16.40.1, Network Type POINT-TO-POINT, Cost: 64
Transmit Delay is 1 sec, State POINT-TO-POINT,
Timer intervals configured, Hello 10, Dead 40, Wait 40, Retransmit 5
Hello due in 00:00:01
Index 1/1, flood queue length 0
Next 0x0(0)/0x0(0)
Last flood scan length is 1, maximum is 1
Last flood scan time is 0 msec, maximum is 0 msec
Neighbor Count is 1 , Adjacent neighbor count is 1
Adjacent with neighbor 172.16.20.1
Suppress hello for 0 neighbor(s)
FastEthernet0/0 is up, line protocol is up
Internet address is 172.16.30.1/24, Area 0
Process ID 102, Router ID 172.16.40.1, Network Type BROADCAST, Cost: 1
Transmit Delay is 1 sec, State DR, Priority 1
Designated Router (ID) 172.16.40.1, Interface address 172.16.30.1
No backup designated router on this network
Timer intervals configured, Hello 10, Dead 40, Wait 40, Retransmit 5
Hello due in 00:00:02
Index 2/2, flood queue length 0
Next 0x0(0)/0x0(0)
Last flood scan length is 1, maximum is 1
Last flood scan time is 0 msec, maximum is 0 msec
Neighbor Count is 0, Adjacent neighbor count is 0
Suppress hello for 0 neighbor(s)
Serial0/0/1 is up, line protocol is up
Internet address is 172.16.40.1/24, Area 0
Process ID 102, Router ID 172.16.40.1, Network Type POINT-TO-POINT, Cost: 64
Transmit Delay is 1 sec, State POINT-TO-POINT,
Timer intervals configured, Hello 10, Dead 40, Wait 40, Retransmit 5
Hello due in 00:00:08
Index 3/3, flood queue length 0
Next 0x0(0)/0x0(0)
Last flood scan length is 1, maximum is 1
Last flood scan time is 0 msec, maximum is 0 msec
Suppress hello for 0 neighbor(s)
we include the three nets conneted to labC in the area.. 20.0, 30.0, and 40.0
link to our left, 20.1 is visible as "Neighbor"
OSPF Database-
Router Link States are
10.1(Router A)
20.1(Router B)
40.1(Router C)(This router)
Net Link States
10.1(Router A)... why does only Router A show here?
Reference- router link state vs net link state
Router Link States are type 1 LSAs. It lists all the routers in the area and the number of interfaces. 40.1 has 4 interfaces
Net Link States are the multi-access networks (Type 2 LSAs). The ADV (advertising router) is the DR.
LabD
LabD(config)#
router ospf 103
LabD(config-router)#
net 172.16.40.2 0.0.0.0 area 0
LabD(config-router)#
net 172.16.50.1 0.0.0.0 area 0
01:37:11: %OSPF-5-ADJCHG: Process 103, Nbr 172.16.40.1
on Serial0/0/0 from LOADING to FULL, Loading Done
LabD#
show ip ospf neighbor
Neighbor ID Pri State Dead Time Address Interface
172.16.40.1 0 FULL/ - 00:00:32 172.16.40.1 Serial0/0/0
LabD#
show ip ospf database
OSPF Router with ID (172.16.50.1) (Process ID 103)
Router Link States (Area 0)
Link ID ADV Router Age Seq# Checksum Link count
172.16.10.1 172.16.10.1 785 0x80000002 0x0067cd 1
172.16.20.1 172.16.20.1 333 0x80000004 0x00a551 3
172.16.40.1 172.16.40.1 111 0x80000005 0x00013b 5
172.16.50.1 172.16.50.1 53 0x80000003 0x001023 3
Net Link States (Area 0)
Link ID ADV Router Age Seq# Checksum
172.16.10.1 172.16.10.1 785 0x80000001 0x00953d
LabD#
show ip ospf interface
Serial0/0/0 is up, line protocol is up
Internet address is 172.16.40.2/24, Area 0
Process ID 103, Router ID 172.16.50.1, Network Type POINT-TO-POINT, Cost: 64
Transmit Delay is 1 sec, State POINT-TO-POINT,
Timer intervals configured, Hello 10, Dead 40, Wait 40, Retransmit 5
Hello due in 00:00:01
Index 1/1, flood queue length 0
Next 0x0(0)/0x0(0)
Last flood scan length is 1, maximum is 1
Last flood scan time is 0 msec, maximum is 0 msec
Neighbor Count is 1 , Adjacent neighbor count is 1
Adjacent with neighbor 172.16.40.1
Suppress hello for 0 neighbor(s)
FastEthernet0/0 is up, line protocol is up
Internet address is 172.16.50.1/24, Area 0
Process ID 103, Router ID 172.16.50.1, Network Type BROADCAST, Cost: 1
Transmit Delay is 1 sec, State WAITING, Priority 1
No designated router on this network
No backup designated router on this network
Timer intervals configured, Hello 10, Dead 40, Wait 40, Retransmit 5
Hello due in 00:00:04
Index 2/2, flood queue length 0
Next 0x0(0)/0x0(0)
Last flood scan length is 1, maximum is 1
Last flood scan time is 0 msec, maximum is 0 msec
Neighbor Count is 0, Adjacent neighbor count is 0
Suppress hello for 0 neighbor(s)
observations
the OSPF databases now match across all 4 routers.
NOTE that this is a database of routers, identified by
router ID. It is not a topology that lists routers AND routes,
like in the "equivalent" eigrp command.show eigrp topology
----------------------------------------------------------------------------------
PAUSE- a tale of a misconfigured network
After a 9 month hiatus, I am reviewing this book and have made it back to Chapter 9. I'm studing this webpage, working thorough the OSPF configurations
described above, and I get stuck on the concept of "link count" under "Router Link States" found in the output of show ip ospf database
The structure of the notes above is helpful, because I was tracking the state of each router BEFORE i made changes to the subsquent router. But just to be sure,
today I decided to recreate the topology, then configure each router one at a time, noting the results as I went.
And I ran into some problems.
Here is the original topology:
And today's recreated toplogy:
After replicating the toplogy and programming the IP addresses on each router, I started on configurations, just like before:
LabA
LabA(config)#
router ospf 100
LabA(config-router)#
net 172.16.10.1 0.0.0.0 area 0
[no output]
LabA#
show ip ospf neighbor
[no output]
LabA#
show ip ospf database
OSPF Router with ID (172.16.10.1) (Process ID 100)
Router Link States (Area 0)
Link ID ADV Router Age Seq# Checksum Link count
172.16.10.1 172.16.10.1 44 0x80000001 0x00b24b 1
LabA#
show ip ospf interface
FastEthernet0/0 is up, line protocol is up
Internet address is 172.16.10.1/24, Area 0
Process ID 100, Router ID 172.16.10.1, Network Type BROADCAST, Cost: 1
Transmit Delay is 1 sec, State DR, Priority 1
Designated Router (ID) 172.16.10.1, Interface address 172.16.10.1
No backup designated router on this network
Timer intervals configured, Hello 10, Dead 40, Wait 40, Retransmit 5
Hello due in 00:00:08
Index 1/1, flood queue length 0
Next 0x0(0)/0x0(0)
Last flood scan length is 1, maximum is 1
Last flood scan time is 0 msec, maximum is 0 msec
Neighbor Count is 0, Adjacent neighbor count is 0
Suppress hello for 0 neighbor(s)
good so far.... On to LabB router
LabB
LabB(config)#
router ospf 101
LabB(config-router)#
net 172.16.10.2 0.0.0.0 area 0
LabB(config-router)#
net 172.16.20.1 0.0.0.0 area 0
01:26:36: %OSPF-5-ADJCHG: Process 101, Nbr 172.16.10.1
on FastEthernet0/0 from LOADING to FULL, Loading Done
LabB#
show ip ospf neighbor
Neighbor ID Pri State Dead Time Address Interface
172.16.10.1 1 FULL/DR 00:00:33 172.16.10.1
LabB#
show ip ospf database
OSPF Router with ID (172.16.20.1) (Process ID 101)
Router Link States (Area 0)
Link ID ADV Router Age Seq# Checksum Link count
172.16.10.1 172.16.10.1 145 0x80000002 0x0067cd 1
172.16.20.1 172.16.20.1 32 0x80000003 0x006e8f 2
Net Link States (Area 0)
Link ID ADV Router Age Seq# Checksum
172.16.10.1 172.16.10.1 145 0x80000001 0x00953d
LabB#
show ip ospf interface
FastEthernet0/0 is up, line protocol is up
Internet address is 172.16.10.2/24, Area 0
Process ID 101, Router ID 172.16.20.1, Network Type BROADCAST, Cost: 1
Transmit Delay is 1 sec, State BDR, Priority 1
Designated Router (ID) 172.16.10.1, Interface address 172.16.10.1
Backup Designated Router (ID) 172.16.20.1, Interface address 172.16.10.2
Timer intervals configured, Hello 10, Dead 40, Wait 40, Retransmit 5
Hello due in 00:00:03
Index 1/1, flood queue length 0
Next 0x0(0)/0x0(0)
Last flood scan length is 1, maximum is 1
Last flood scan time is 0 msec, maximum is 0 msec
Neighbor Count is 1, Adjacent neighbor count is 1
Adjacent with neighbor 172.16.10.1 (Designated Router)
Suppress hello for 0 neighbor(s)
Serial0/0/0 is up, line protocol is up
Internet address is 172.16.20.1/24, Area 0
Process ID 101, Router ID 172.16.20.1, Network Type POINT-TO-POINT, Cost: 64
Transmit Delay is 1 sec, State POINT-TO-POINT,
Timer intervals configured, Hello 10, Dead 40, Wait 40, Retransmit 5
Hello due in 00:00:04
Index 2/2, flood queue length 0
Next 0x0(0)/0x0(0)
Last flood scan length is 1, maximum is 1
Last flood scan time is 0 msec, maximum is 0 msec
Suppress hello for 0 neighbor(s)
still looks good; same as before.... On to LabC router
LabC
LabC(config)#
router ospf 102
LabC(config-router)#
net 172.16.20.2 0.0.0.0 area 0
LabC(config-router)#
net 172.16.30.1 0.0.0.0 area 0
LabC(config-router)#
net 172.16.40.1 0.0.0.0 area 0
01:33:54: %OSPF-5-ADJCHG: Process 102, Nbr 172.16.20.1
on Serial0/0/0 from LOADING to FULL, Loading Done
LabC#
show ip ospf neighbor
[no output]
And here is where I ran into trouble. The show ip ospf neighbor command returns nothing. How can
that be?
After awhile I realized it is due to a misconfiguration in the topology.
For Lab C, I programmed the interfaces as follows:
LabC(config)#
int f0/0
LabC(config-if)#
ip addr 172.16.30.1 255.255.255.0
LabC(config-if)#
no shut
LabC(config-if)#
int s0/0/0
LabC(config-if)#
ip addr 172.16.20.2 255.255.255.0
LabC(config-if)#
no shut
LabC(config-if)#
int s0/0/1
LabC(config-if)#
ip addr 172.16.40.1 255.255.255.0
LabC(config-if)#
no shut
and again here is the topology for that router:
but here is what it SHOULD HAVE looked like (as it did the first time I built it)
S0/0/0 and S0/0/1 are swapped. When I gave the IP 172.16.20.2 to s/0/0/0, thinking that was the interface on the left side
which faces Lab B, I was actually giving 172.16.20.2 to the right side, facing LabC (which has no OSPF configs yet.)
Since the left side got got the IP intended for the right side which was 172.16.40.1
the inverse also occured-
the right side got the IP intended for the left which was 172.16.20.2
LabC left side should have been
s0/0/0 with 20.2
and LabC right side should have been
s0/0/1 with 40.1
The correct IPs were mapped to the correct interfaces. But the mistake happened before I even programmed them.
When I made the connections from LabB to LabC and from LabD to LabC, I plugged then into the wrong ports.
Interestingly.. not only is this causing OSPF to not see B as a neighbor from C.. but B and C cannot ping eachother either.
@B the config is 172.16.20.1/24 @ S0/0/0
@C the config is 172.16.40.1/24 @ S/0/0/1
meaning they are not even on the same network! But the system is not throwing any errors or bringing it to my attention.
It just fails to connect.
To correct the issue, I simply deleted those two links and re-created them. Worth noting, I used the auto select cable here,
which does not ask which interface you want to use when attaching. Earlier I must have plugged the right side first, and
auto select plugged into 0/0/0.
This time I plugged into left side first.
Now LabC OSPF data is reading out correctly...
LabC
LabC(config)#
router ospf 102
LabC(config-router)#
net 172.16.20.2 0.0.0.0 area 0
LabC(config-router)#
net 172.16.30.1 0.0.0.0 area 0
LabC(config-router)#
net 172.16.40.1 0.0.0.0 area 0
01:33:54: %OSPF-5-ADJCHG: Process 102, Nbr 172.16.20.1
on Serial0/0/0 from LOADING to FULL, Loading Done
LabC#
show ip ospf neighbor
Neighbor ID Pri State Dead Time Address Interface
172.16.20.1 0 FULL/ - 00:00:30 172.16.20.1 Serial0/0/0
LabC#
show ip ospf database
OSPF Router with ID (172.16.40.1) (Process ID 102)
Router Link States (Area 0)
Link ID ADV Router Age Seq# Checksum Link count
172.16.10.1 172.16.10.1 542 0x80000002 0x0067cd 1
172.16.20.1 172.16.20.1 90 0x80000004 0x00a551 3
172.16.40.1 172.16.40.1 37 0x80000004 0x00e47c 4
Net Link States (Area 0)
Link ID ADV Router Age Seq# Checksum
172.16.10.1 172.16.10.1 542 0x80000001 0x00953d
LabC#
show ip ospf interface
Serial0/0/0 is up, line protocol is up
Internet address is 172.16.20.2/24, Area 0
Process ID 102, Router ID 172.16.40.1, Network Type POINT-TO-POINT, Cost: 64
Transmit Delay is 1 sec, State POINT-TO-POINT,
Timer intervals configured, Hello 10, Dead 40, Wait 40, Retransmit 5
Hello due in 00:00:01
Index 1/1, flood queue length 0
Next 0x0(0)/0x0(0)
Last flood scan length is 1, maximum is 1
Last flood scan time is 0 msec, maximum is 0 msec
Neighbor Count is 1 , Adjacent neighbor count is 1
Adjacent with neighbor 172.16.20.1
Suppress hello for 0 neighbor(s)
FastEthernet0/0 is up, line protocol is up
Internet address is 172.16.30.1/24, Area 0
Process ID 102, Router ID 172.16.40.1, Network Type BROADCAST, Cost: 1
Transmit Delay is 1 sec, State DR, Priority 1
Designated Router (ID) 172.16.40.1, Interface address 172.16.30.1
No backup designated router on this network
Timer intervals configured, Hello 10, Dead 40, Wait 40, Retransmit 5
Hello due in 00:00:02
Index 2/2, flood queue length 0
Next 0x0(0)/0x0(0)
Last flood scan length is 1, maximum is 1
Last flood scan time is 0 msec, maximum is 0 msec
Neighbor Count is 0, Adjacent neighbor count is 0
Suppress hello for 0 neighbor(s)
Serial0/0/1 is up, line protocol is up
Internet address is 172.16.40.1/24, Area 0
Process ID 102, Router ID 172.16.40.1, Network Type POINT-TO-POINT, Cost: 64
Transmit Delay is 1 sec, State POINT-TO-POINT,
Timer intervals configured, Hello 10, Dead 40, Wait 40, Retransmit 5
Hello due in 00:00:08
Index 3/3, flood queue length 0
Next 0x0(0)/0x0(0)
Last flood scan length is 1, maximum is 1
Last flood scan time is 0 msec, maximum is 0 msec
Suppress hello for 0 neighbor(s)
Which brings me to the original reason I re-created this topology... I was confused about the LINK COUNTS
here:
OSPF Router with ID (172.16.40.1) (Process ID 102)
Router Link States (Area 0)
Link ID ADV Router Age Seq# Checksum Link count
172.16.10.1 172.16.10.1 542 0x80000002 0x0067cd 1
172.16.20.1 172.16.20.1 90 0x80000004 0x00a551 3
172.16.40.1 172.16.40.1 37 0x80000004 0x00e47c 4
Net Link States (Area 0)
Link ID ADV Router Age Seq# Checksum
172.16.10.1 172.16.10.1 542 0x80000001 0x00953d
The steps of recreating the lab were helpful, but this link answered the question:
Here is the output of each router's command show ip ospf interface as they are
set up one at a time.
LabA - No OSPF at B, C, or D yet
show ip ospf database
OSPF Router with ID (172.16.10.1) (Process ID 100)
Router Link States (Area 0)
Link ID ADV Router Age Seq# Checksum Link count
172.16.10.1 172.16.10.1 44 0x80000001 0x00b24b 1
LabB - No OSPF at C or D yet
show ip ospf database
OSPF Router with ID (172.16.20.1) (Process ID 101)
Router Link States (Area 0)
Link ID ADV Router Age Seq# Checksum Link count
172.16.10.1 172.16.10.1 145 0x80000002 0x0067cd 1
172.16.20.1 172.16.20.1 32 0x80000003 0x006e8f 2
Net Link States (Area 0)
Link ID ADV Router Age Seq# Checksum
172.16.10.1 172.16.10.1 145 0x80000001 0x00953d
the 20.2 interface on this router has 2 ospf links.
The left-facing out to RA, a crossover cable
The right-facing out to RC, a serial cable.
If the solution I found is correct, why is this serial link not being counted twice? The solution (I think)
is revealed after the configuration of the next router...
LabC - No OSPF at D yet
show ip ospf database
OSPF Router with ID (172.16.40.1) (Process ID 102)
Router Link States (Area 0)
Link ID ADV Router Age Seq# Checksum Link count
172.16.10.1 172.16.10.1 542 0x80000002 0x0067cd 1
172.16.20.1 172.16.20.1 90 0x80000004 0x00a551 3
172.16.40.1 172.16.40.1 37 0x80000004 0x00e47c 4
Net Link States (Area 0)
Link ID ADV Router Age Seq# Checksum
172.16.10.1 172.16.10.1 542 0x80000001 0x00953d
NOW we can see that the 20.1 link, which is the right-facing interface on LabB.. aka the router ID..
has THREE OSPF links.
Nothing changed on the left side of B. But on the right side, we now have an active OSPF router at the
other end of the link. This leads me to believe that the forum post was correct that 'serial links are counted twice',
but, more specifically, BOTH ENDS of the serial(PPP) link are counted... IF there is an OSPF router on each end.
This is backed up by the fact that LabC, OSPF id 40.1, has four OSPF links. The top-facing link to the 30
network DOES count.. even though it has no OSPF router on the other end. It counts because it's not a serial link.
The requirement of having an OSPF router on the other end for an interface to count here, only applies
to serial links. And pertains to BOTH ends of the link being counted.
In LabC's case, we have one serial at left, being counted twice. One ethernet at top, being counted once. And
one serial at right only being counted once because LabD is not active with OSPF yet.
If this is correct, then we should see Lab C's 40.1 count go to 5 after LabD is set for OSPF....
LabD - all 4 routers have OSPF
show ip ospf database
OSPF Router with ID (172.16.50.1) (Process ID 103)
Router Link States (Area 0)
Link ID ADV Router Age Seq# Checksum Link count
172.16.10.1 172.16.10.1 785 0x80000002 0x0067cd 1
172.16.20.1 172.16.20.1 333 0x80000004 0x00a551 3
172.16.40.1 172.16.40.1 111 0x80000005 0x00013b 5
172.16.50.1 172.16.50.1 53 0x80000003 0x001023 3
Net Link States (Area 0)
Link ID ADV Router Age Seq# Checksum
172.16.10.1 172.16.10.1 785 0x80000001 0x00953d
and back to LabC.....
show ip ospf database
OSPF Router with ID (172.16.40.1) (Process ID 102)
Router Link States (Area 0)
Link ID ADV Router Age Seq# Checksum Link count
172.16.10.1 172.16.10.1 1174 0x80000002 0x0067cd 1
172.16.20.1 172.16.20.1 722 0x80000004 0x00a551 3
172.16.40.1 172.16.40.1 500 0x80000005 0x00013b 5
172.16.50.1 172.16.50.1 441 0x80000003 0x001023 3
Net Link States (Area 0)
Link ID ADV Router Age Seq# Checksum
172.16.10.1 172.16.10.1 1174 0x80000001 0x00953d
Looks good! The link count for each router makes sense if you count the serial interfaces twice (one for each end).
the OSPF databases now match across all 4 routers.
NOTE that this is a database of routers, identified by
router ID. It is not a topology that lists routers AND routes, like in
the "equivalent" eigrp command show eigrp topology
Note that the .30 network is NOT represented here.
LabA#
show ip ospf database
OSPF Router with ID (172.16.10.1) (Process ID 100)
Router Link States (Area 0)
Link ID ADV Router Age Seq# Checksum Link count
172.16.10.1 172.16.10.1 1138 0x80000002 0x0067cd 1
172.16.20.1 172.16.20.1 686 0x80000004 0x00a551 3
172.16.40.1 172.16.40.1 463 0x80000005 0x00013b 5
172.16.50.1 172.16.50.1 404 0x80000003 0x001023 3
Net Link States (Area 0)
Link ID ADV Router Age Seq# Checksum
172.16.10.1 172.16.10.1 1138 0x80000001 0x00953d
LabB#
show ip ospf database
OSPF Router with ID (172.16.20.1) (Process ID 101)
Router Link States (Area 0)
Link ID ADV Router Age Seq# Checksum Link count
172.16.10.1 172.16.10.1 1151 0x80000002 0x0067cd 1
172.16.20.1 172.16.20.1 699 0x80000004 0x00a551 3
172.16.40.1 172.16.40.1 476 0x80000005 0x00013b 5
172.16.50.1 172.16.50.1 417 0x80000003 0x001023 3
Net Link States (Area 0)
Link ID ADV Router Age Seq# Checksum
172.16.10.1 172.16.10.1 1151 0x80000001 0x00953d
LabC#
show ip ospf database
OSPF Router with ID (172.16.40.1) (Process ID 102)
Router Link States (Area 0)
Link ID ADV Router Age Seq# Checksum Link count
172.16.10.1 172.16.10.1 1174 0x80000002 0x0067cd 1
172.16.20.1 172.16.20.1 722 0x80000004 0x00a551 3
172.16.40.1 172.16.40.1 500 0x80000005 0x00013b 5
172.16.50.1 172.16.50.1 441 0x80000003 0x001023 3
Net Link States (Area 0)
Link ID ADV Router Age Seq# Checksum
172.16.10.1 172.16.10.1 1174 0x80000001 0x00953d
LabD#
show ip ospf database
OSPF Router with ID (172.16.50.1) (Process ID 103)
Router Link States (Area 0)
Link ID ADV Router Age Seq# Checksum Link count
172.16.10.1 172.16.10.1 785 0x80000002 0x0067cd 1
172.16.20.1 172.16.20.1 333 0x80000004 0x00a551 3
172.16.40.1 172.16.40.1 111 0x80000005 0x00013b 5
172.16.50.1 172.16.50.1 53 0x80000003 0x001023 3
Net Link States (Area 0)
Link ID ADV Router Age Seq# Checksum
172.16.10.1 172.16.10.1 785 0x80000001 0x00953d
Below is our routing tables with OSPF data. We do see the .30 network here.
Everyone can reach it:
LabA via LabB's 10.2
LabB via LabC's 20.2
LabC via direct connection
LabD via LabC's 40.1
LabA#
show ip route
172.16.0.0/16 is variably subnetted, 6 subnets, 2 masks
C 172.16.10.0/24 is directly connected, FastEthernet0/0
L 172.16.10.1/32 is directly connected, FastEthernet0/0
O 172.16.20.0/24 [110/65] via 172.16.10.2, 00:28:03, FastEthernet0/0
O 172.16.30.0/24 [110/66] via 172.16.10.2, 00:21:35, FastEthernet0/0
O 172.16.40.0/24 [110/129] via 172.16.10.2, 00:21:25, FastEthernet0/0
O 172.16.50.0/24 [110/130] via 172.16.10.2, 00:17:40, FastEthernet0/0
LabB#
show ip route
172.16.0.0/16 is variably subnetted, 7 subnets, 2 masks
C 172.16.10.0/24 is directly connected, FastEthernet0/0
L 172.16.10.2/32 is directly connected, FastEthernet0/0
C 172.16.20.0/24 is directly connected, Serial0/0/0
L 172.16.20.1/32 is directly connected, Serial0/0/0
O 172.16.30.0/24 [110/65] via 172.16.20.2, 00:27:04, Serial0/0/0
O 172.16.40.0/24 [110/128] via 172.16.20.2, 00:26:54, Serial0/0/0
O 172.16.50.0/24 [110/129] via 172.16.20.2, 00:23:09, Serial0/0/0
LabC#
show ip route
172.16.0.0/16 is variably subnetted, 8 subnets, 2 masks
O 172.16.10.0/24 [110/65] via 172.16.20.1, 00:27:52, Serial0/0/0
C 172.16.20.0/24 is directly connected, Serial0/0/0
L 172.16.20.2/32 is directly connected, Serial0/0/0
C 172.16.30.0/24 is directly connected, FastEthernet0/0
L 172.16.30.1/32 is directly connected, FastEthernet0/0
C 172.16.40.0/24 is directly connected, Serial0/0/1
L 172.16.40.1/32 is directly connected, Serial0/0/1
O 172.16.50.0/24 [110/65] via 172.16.40.2, 00:23:36, Serial0/0/1
LabD#
show ip route
172.16.0.0/16 is variably subnetted, 7 subnets, 2 masks
O 172.16.10.0/24 [110/129] via 172.16.40.1, 00:25:20, Serial0/0/0
O 172.16.20.0/24 [110/128] via 172.16.40.1, 00:25:20, Serial0/0/0
O 172.16.30.0/24 [110/65] via 172.16.40.1, 00:25:20, Serial0/0/0
C 172.16.40.0/24 is directly connected, Serial0/0/0
L 172.16.40.2/32 is directly connected, Serial0/0/0
C 172.16.50.0/24 is directly connected, FastEthernet0/0
L 172.16.50.1/32 is directly connected, FastEthernet0/0
moving on.......
9.5 - OSPF DR and BDR Elections
EachRouter(config)#
hostname X (A, B, or C)
EachRouter(config)#
line con 0
EachRouter(config-line)#
exec-timeout 0 0
A(config)#
int f0/0
A(config-if)#
ip addr 10.1.1.1 255.255.255.0
A(config-if)#
no shut
A(config)#
router ospf 12345
A(config-router)#
net 10.1.1.0 0.0.0.255 area 0
00:23:30: %OSPF-5-ADJCHG: Process 12345, Nbr 10.1.1.3 on FastEthernet0/0 from LOADING to FULL, Loading Done
00:23:30: %OSPF-5-ADJCHG: Process 12345, Nbr 10.1.1.2 on FastEthernet0/0 from LOADING to FULL, Loading Done
A#
show ip ospf int
note this output was generated AFTER all 3 routers set for OSPF
FastEthernet0/0 is up, line protocol is up
Internet address is 10.1.1.1/24, Area 0
Process ID 12345, Router ID 10.1.1.1, Network Type BROADCAST, Cost: 1
Transmit Delay is 1 sec, State DROTHER, Priority 1
Designated Router (ID) 10.1.1.3, Interface address 10.1.1.3
Backup Designated Router (ID) 10.1.1.2, Interface address 10.1.1.2
Timer intervals configured, Hello 10, Dead 40, Wait 40, Retransmit 5
Hello due in 00:00:04
Index 1/1, flood queue length 0
Next 0x0(0)/0x0(0)
Last flood scan length is 1, maximum is 1
Last flood scan time is 0 msec, maximum is 0 msec
Neighbor Count is 2, Adjacent neighbor count is 2
Adjacent with neighbor 10.1.1.3 (Designated Router)
Adjacent with neighbor 10.1.1.2 (Backup Designated Router)
Suppress hello for 0 neighbor(s)
A(config-if)#shut
A(config-if)#
%LINK-5-CHANGED: Interface FastEthernet0/0, changed state to administratively down
%LINEPROTO-5-UPDOWN: Line protocol on Interface FastEthernet0/0, changed state to down
00:40:28: %OSPF-5-ADJCHG: Process 12345, Nbr 10.1.1.2 on FastEthernet0/0 from FULL to DOWN, Neighbor Down: Interface down or detached
00:40:28: OSPF: Build router LSA for area 0, router ID 10.1.1.1, seq 0xffffffff80000003
00:40:28: %OSPF-5-ADJCHG: Process 12345, Nbr 10.1.1.3 on FastEthernet0/0 from FULL to DOWN, Neighbor Down: Interface down or detached
00:40:28: OSPF: Build router LSA for area 0, router ID 10.1.1.1, seq 0xffffffff80000004
00:40:28: OSPF: Build router LSA for area 0, router ID 10.1.1.1, seq 0xffffffff80000004
A(config-if)#no shut
A(config-if)#
%LINK-5-CHANGED: Interface FastEthernet0/0, changed state to up
%LINEPROTO-5-UPDOWN: Line protocol on Interface FastEthernet0/0, changed state to up
00:40:48: OSPF: Build router LSA for area 0, router ID 10.1.1.1, seq 0xffffffff80000004
00:41:27: OSPF: Backup seen Event before WAIT timer on FastEthernet0/0
00:41:27: OSPF: DR/BDR election on FastEthernet0/0
00:41:27: OSPF: Elect BDR 10.1.1.2
00:41:27: OSPF: Elect DR 10.1.1.3
00:41:27: DR: 10.1.1.3 (Id) BDR: 10.1.1.2 (Id)
00:41:27: OSPF: Send DBD to 10.1.1.3 on FastEthernet0/0 seq 0x5accb8e2 opt 0x00 flag 0x7 len 32
B(config)#
int f0/0
B(config-if)#
ip addr 10.1.1.2 255.255.255.0
B(config-if)#
no shut
B(config)#
router ospf 12345
B(config-router)#
net 10.1.1.0 0.0.0.255 area 0
00:23:29: %OSPF-5-ADJCHG: Process 12345, Nbr 10.1.1.3 on FastEthernet0/0 from LOADING to FULL, Loading Done
00:23:29: %OSPF-5-ADJCHG: Process 12345, Nbr 10.1.1.1 on FastEthernet0/0 from LOADING to FULL, Loading Done
B#
show ip ospf int
note this output was generated AFTER all 3 routers set for OSPF
FastEthernet0/0 is up, line protocol is up
Internet address is 10.1.1.2/24, Area 0
Process ID 12345, Router ID 10.1.1.2, Network Type BROADCAST, Cost: 1
Transmit Delay is 1 sec, State BDR, Priority 1
Designated Router (ID) 10.1.1.3, Interface address 10.1.1.3
Backup Designated Router (ID) 10.1.1.2, Interface address 10.1.1.2
Timer intervals configured, Hello 10, Dead 40, Wait 40, Retransmit 5
Hello due in 00:00:05
Index 1/1, flood queue length 0
Next 0x0(0)/0x0(0)
Last flood scan length is 1, maximum is 1
Last flood scan time is 0 msec, maximum is 0 msec
Neighbor Count is 2, Adjacent neighbor count is 2
Adjacent with neighbor 10.1.1.1
Adjacent with neighbor 10.1.1.3 (Designated Router)
Suppress hello for 0 neighbor(s)
B#debug ip ospf adj
OSPF adjacency events debugging is on
B#
00:39:21: OSPF: DR/BDR election on FastEthernet0/0
00:39:21: OSPF: Elect BDR 10.1.1.2
00:39:21: OSPF: Elect DR 10.1.1.3
00:39:21: DR: 10.1.1.3 (Id) BDR: 10.1.1.2 (Id)
00:41:01: %OSPF-5-ADJCHG: Process 12345, Nbr 10.1.1.1 on FastEthernet0/0 from FULL to DOWN, Neighbor Down: Dead timer expired
00:41:01: %OSPF-5-ADJCHG: Process 12345, Nbr 10.1.1.1 on FastEthernet0/0 from FULL to DOWN, Neighbor Down: Interface down or detached
00:41:01: OSPF: Build router LSA for area 0, router ID 10.1.1.2, seq 0xffffffff80000003
00:41:01: OSPF: DR/BDR election on FastEthernet0/0
00:41:01: OSPF: Elect BDR 10.1.1.2
00:41:01: OSPF: Elect DR 10.1.1.3
C(config)#
int f0/0
C(config-if)#
ip addr 10.1.1.3 255.255.255.0
C(config-if)#
no shut
C(config)#
router ospf 12345
C(config-router)#
net 10.1.1.0 0.0.0.255 area 0
00:23:27: %OSPF-5-ADJCHG: Process 12345, Nbr 10.1.1.1 on FastEthernet0/0 from LOADING to FULL, Loading Done
00:23:27: %OSPF-5-ADJCHG: Process 12345, Nbr 10.1.1.2 on FastEthernet0/0 from LOADING to FULL, Loading Done
C#
show ip ospf int
note this output was generated AFTER all 3 routers set for OSPF
FastEthernet0/0 is up, line protocol is up
Internet address is 10.1.1.3/24, Area 0
Process ID 12345, Router ID 10.1.1.3, Network Type BROADCAST, Cost: 1
Transmit Delay is 1 sec, State DR, Priority 1
Designated Router (ID) 10.1.1.3, Interface address 10.1.1.3
Backup Designated Router (ID) 10.1.1.2, Interface address 10.1.1.2
Timer intervals configured, Hello 10, Dead 40, Wait 40, Retransmit 5
Hello due in 00:00:00
Index 1/1, flood queue length 0
Next 0x0(0)/0x0(0)
Last flood scan length is 1, maximum is 1
Last flood scan time is 0 msec, maximum is 0 msec
Neighbor Count is 2, Adjacent neighbor count is 2
Adjacent with neighbor 10.1.1.1
Adjacent with neighbor 10.1.1.2 (Backup Designated Router)
Suppress hello for 0 neighbor(s)
C#debug ip ospf adj
OSPF adjacency events debugging is on
C#
00:39:19: OSPF: DR/BDR election on FastEthernet0/0
00:39:19: OSPF: Elect BDR 10.1.1.2
00:39:19: OSPF: Elect DR 10.1.1.3
00:39:19: DR: 10.1.1.3 (Id) BDR: 10.1.1.2 (Id)
00:40:59: %OSPF-5-ADJCHG: Process 12345, Nbr 10.1.1.1 on FastEthernet0/0 from FULL to DOWN, Neighbor Down: Dead timer expired
00:40:59: %OSPF-5-ADJCHG: Process 12345, Nbr 10.1.1.1 on FastEthernet0/0 from FULL to DOWN, Neighbor Down: Interface down or detached
00:40:59: OSPF: Build router LSA for area 0, router ID 10.1.1.3, seq 0xffffffff80000003
00:40:59: OSPF: Build net LSA for area 0, router ID 10.1.1.3, seq 0xffffffff80000003
00:40:59: OSPF: DR/BDR election on FastEthernet0/0
00:40:59: OSPF: Elect BDR 10.1.1.2
00:40:59: OSPF: Elect DR 10.1.1.3
DR and BDR automtically set based on higest IP address
Note our network type is BROADCAST because we're using ethernet interfaces...
it would be point-to-point if using a serial connection
we want to manually overide the priority of the router. ZERO priority means it wont participate in the election process
MAX priority of 255 means no other router can beat it for DR
We'll set the priority for router A to 3.
It will beome the DR only after we shut/no shut the interface router
AND
manually power on/off the other two routers
A(config)#
int f0/0
A(config-int)#
ip ospf priority 3
A(config-int)#
shut
A(config-int)#
no shut
A#
debug ip ospf adj
B#
debug ip ospf adj
00:05:50: OSPF: DR/BDR election on FastEthernet0/0
00:05:50: OSPF: Elect BDR 10.1.1.2
00:05:50: OSPF: Elect DR 10.1.1.1
00:05:50: OSPF: Elect BDR 10.1.1.2
00:05:50: OSPF: Elect DR 10.1.1.1
00:05:50: DR: 10.1.1.1 (Id) BDR: 10.1.1.2 (Id)
00:05:50: OSPF: Send DBD to 10.1.1.1 on FastEthernet0/0 seq 0x10164ebb opt 0x00 flag 0x7 len 32
00:05:50: OSPF: Build router LSA for area 0, router ID 10.1.1.2, seq 0xffffffff80000002
00:05:52: OSPF: Rcv DBD from 10.1.1.1 on FastEthernet0/0 seq 0x20368093 opt 0x00 flag 0x7 len 32 mtu 1500 state EXSTART
00:05:52: OSPF: First DBD and we are not SLAVE
00:05:55: OSPF: Send DBD to 10.1.1.1 on FastEthernet0/0 seq 0x10164ebb opt 0x00 flag 0x7 len 32
00:05:55: OSPF: Rcv DBD from 10.1.1.1 on FastEthernet0/0 seq 0x10164ebb opt 0x00 flag 0x2 len 112 mtu 1500 state EXSTART
00:05:55: OSPF: NBR Negotiation Done. We are the MASTER
00:05:55: OSPF: Send DBD to 10.1.1.1 on FastEthernet0/0 seq 0x10164ebc opt 0x00 flag 0x3 len 52
00:05:55: OSPF: Rcv DBD from 10.1.1.1 on FastEthernet0/0 seq 0x10164ebc opt 0x00 flag 0x0 len 32 mtu 1500 state EXCHANGE
00:05:55: OSPF: Send DBD to 10.1.1.1 on FastEthernet0/0 seq 0x10164ebd opt 0x00 flag 0x1 len 32
00:05:55: OSPF: Rcv DBD from 10.1.1.1 on FastEthernet0/0 seq 0x10164ebd opt 0x00 flag 0x0 len 32 mtu 1500 state EXCHANGE
00:05:55: Exchange Done with 10.1.1.1 on FastEthernet0/0
00:05:55: OSPF: Database request to 10.1.1.1
00:05:55: OSPF: sent LS REQ packet to 10.1.1.1, length 36
00:05:55: OSPF: Rcv DBD from 10.1.1.1 on FastEthernet0/0 seq 0x10164ebd opt 0x00 flag 0x0 len 32 mtu 1500 state LOADING
00:05:55: Synchronized with with 10.1.1.1 on FastEthernet0/0, state FULL
00:05:55: %OSPF-5-ADJCHG: Process 12345, Nbr 10.1.1.1 on FastEthernet0/0 from LOADING to FULL, Loading Done
00:05:55: OSPF: Build router LSA for area 0, router ID 10.1.1.2, seq 0xffffffff80000002
C#
debug ip ospf adj
00:06:13: OSPF: DR/BDR election on FastEthernet0/0
00:06:13: OSPF: Elect BDR 10.1.1.2
00:06:13: OSPF: Elect DR 10.1.1.1
00:06:13: DR: 10.1.1.1 (Id) BDR: 10.1.1.2 (Id)
00:06:13: OSPF: Send DBD to 10.1.1.1 on FastEthernet0/0 seq 0x1cc5536d opt 0x00 flag 0x7 len 32
00:06:13: OSPF: Send DBD to 10.1.1.2 on FastEthernet0/0 seq 0x3d51ca66 opt 0x00 flag 0x7 len 32
00:06:13: OSPF: Build router LSA for area 0, router ID 10.1.1.3, seq 0xffffffff80000002
00:06:17: OSPF: Rcv DBD from 10.1.1.1 on FastEthernet0/0 seq 0x6b532eec opt 0x00 flag 0x7 len 32 mtu 1500 state EXSTART
00:06:17: OSPF: First DBD and we are not SLAVE
00:06:17: OSPF: Rcv DBD from 10.1.1.2 on FastEthernet0/0 seq 0x783110f4 opt 0x00 flag 0x7 len 32 mtu 1500 state EXSTART
00:06:17: OSPF: First DBD and we are not SLAVE
00:06:18: OSPF: Send DBD to 10.1.1.2 on FastEthernet0/0 seq 0x3d51ca66 opt 0x00 flag 0x7 len 32
00:06:18: OSPF: Send DBD to 10.1.1.1 on FastEthernet0/0 seq 0x1cc5536d opt 0x00 flag 0x7 len 32
00:06:18: OSPF: Rcv DBD from 10.1.1.2 on FastEthernet0/0 seq 0x3d51ca66 opt 0x00 flag 0x2 len 132 mtu 1500 state EXSTART
00:06:18: OSPF: NBR Negotiation Done. We are the MASTER
00:06:18: OSPF: Send DBD to 10.1.1.2 on FastEthernet0/0 seq 0x3d51ca67 opt 0x00 flag 0x3 len 52
00:06:18: OSPF: Rcv DBD from 10.1.1.1 on FastEthernet0/0 seq 0x1cc5536d opt 0x00 flag 0x2 len 132 mtu 1500 state EXSTART
00:06:18: OSPF: NBR Negotiation Done. We are the MASTER
00:06:18: OSPF: Send DBD to 10.1.1.1 on FastEthernet0/0 seq 0x1cc5536e opt 0x00 flag 0x3 len 52
00:06:18: OSPF: Rcv DBD from 10.1.1.2 on FastEthernet0/0 seq 0x3d51ca67 opt 0x00 flag 0x0 len 32 mtu 1500 state EXCHANGE
00:06:18: OSPF: Send DBD to 10.1.1.2 on FastEthernet0/0 seq 0x3d51ca68 opt 0x00 flag 0x1 len 32
00:06:18: OSPF: Rcv DBD from 10.1.1.1 on FastEthernet0/0 seq 0x1cc5536e opt 0x00 flag 0x0 len 32 mtu 1500 state EXCHANGE
00:06:18: OSPF: Send DBD to 10.1.1.1 on FastEthernet0/0 seq 0x1cc5536f opt 0x00 flag 0x1 len 32
00:06:18: OSPF: Rcv DBD from 10.1.1.2 on FastEthernet0/0 seq 0x3d51ca68 opt 0x00 flag 0x0 len 32 mtu 1500 state EXCHANGE
00:06:18: Exchange Done with 10.1.1.2 on FastEthernet0/0
00:06:18: OSPF: Database request to 10.1.1.2
00:06:18: OSPF: sent LS REQ packet to 10.1.1.2, length 48
00:06:18: OSPF: Rcv DBD from 10.1.1.1 on FastEthernet0/0 seq 0x1cc5536f opt 0x00 flag 0x0 len 32 mtu 1500 state EXCHANGE
verify on all three routers
A#
show ip ospf interface f0/0
FastEthernet0/0 is up, line protocol is up
Internet address is 10.1.1.1/24, Area 0
Process ID 12345, Router ID 10.1.1.1, Network Type BROADCAST, Cost: 1
Transmit Delay is 1 sec, State DR, Priority 3
Designated Router (ID) 10.1.1.1, Interface address 10.1.1.1
Backup Designated Router (ID) 10.1.1.2, Interface address 10.1.1.2
Timer intervals configured, Hello 10, Dead 40, Wait 40, Retransmit 5
Hello due in 00:00:09
Index 1/1, flood queue length 0
Next 0x0(0)/0x0(0)
Last flood scan length is 1, maximum is 1
Last flood scan time is 0 msec, maximum is 0 msec
Neighbor Count is 2, Adjacent neighbor count is 2
Adjacent with neighbor 10.1.1.2 (Backup Designated Router)
Adjacent with neighbor 10.1.1.3
Suppress hello for 0 neighbor(s)
A#
show ip ospf neighbor
Neighbor ID Pri State Dead Time Address Interface
10.1.1.2 1 FULL/BDR 00:00:37 10.1.1.2 FastEthernet0/0
10.1.1.3 1 FULL/DROTHER 00:00:30 10.1.1.3 FastEthernet0/0
B#
show ip ospf interface f0/0
FastEthernet0/0 is up, line protocol is up
Internet address is 10.1.1.2/24, Area 0
Process ID 12345, Router ID 10.1.1.2, Network Type BROADCAST, Cost: 1
Transmit Delay is 1 sec, State BDR, Priority 1
Designated Router (ID) 10.1.1.1, Interface address 10.1.1.1
Backup Designated Router (ID) 10.1.1.2, Interface address 10.1.1.2
Timer intervals configured, Hello 10, Dead 40, Wait 40, Retransmit 5
Hello due in 00:00:08
Index 1/1, flood queue length 0
Next 0x0(0)/0x0(0)
Last flood scan length is 1, maximum is 1
Last flood scan time is 0 msec, maximum is 0 msec
Neighbor Count is 2, Adjacent neighbor count is 2
Adjacent with neighbor 10.1.1.1 (Designated Router)
Adjacent with neighbor 10.1.1.3
Suppress hello for 0 neighbor(s)
B#
show ip ospf neighbor
Neighbor ID Pri State Dead Time Address Interface
10.1.1.1 3 FULL/DR 00:00:35 10.1.1.1 FastEthernet0/0
10.1.1.3 1 FULL/DROTHER 00:00:31 10.1.1.3 FastEthernet0/0
C#
show ip ospf interface f0/0
FastEthernet0/0 is up, line protocol is up
Internet address is 10.1.1.3/24, Area 0
Process ID 12345, Router ID 10.1.1.3, Network Type BROADCAST, Cost: 1
Transmit Delay is 1 sec, State DROTHER, Priority 1
Designated Router (ID) 10.1.1.1, Interface address 10.1.1.1
Backup Designated Router (ID) 10.1.1.2, Interface address 10.1.1.2
Timer intervals configured, Hello 10, Dead 40, Wait 40, Retransmit 5
Hello due in 00:00:06
Index 1/1, flood queue length 0
Next 0x0(0)/0x0(0)
Last flood scan length is 1, maximum is 1
Last flood scan time is 0 msec, maximum is 0 msec
Neighbor Count is 2, Adjacent neighbor count is 2
Adjacent with neighbor 10.1.1.1 (Designated Router)
Adjacent with neighbor 10.1.1.2 (Backup Designated Router)
Suppress hello for 0 neighbor(s)
C#
show ip ospf neighbor/span>
Neighbor ID Pri State Dead Time Address Interface
10.1.1.1 3 FULL/DR 00:00:35 10.1.1.1 FastEthernet0/0
10.1.1.2 1 FULL/BDR 00:00:37 10.1.1.2 FastEthernet0/0
Router1 is the DR with priority 3
still need more work to understand the output of the defbu ospf adj
Chapter 9 Review Questions
1. There are three possible routes for a router to reach a destination network:
OSPF with a metric of 782
RIPv2 with a metric of 4
EIGRP with a composite metric of 20514560
Which route will be installed in the routing table?
EIGRP because it has the lowest Administrative Distance, and AD is always used before metric
ADs are:
ExternalEIGRP 170
RIP 120
OSPF 110
IGRP 100
EIGRP 90
Static 1
Connected 0
2. Which EIGRP information is held in RAM and maintained through the use of Hello and update packets?
Neighbor table
and
toplogy table
3. Describe the process identifier that is used to run OSPF on a router
The OSPF process id is only locally significant. A random number can be selected. But it's required in order to identify
a unique OSPF database instance. You can use the same, or a different number on each router, doesnt matter.
Any number can be used from 1 to 65,535. Process ID is supplied as an argument to the command router ospf
NOT to be confused with the area number which can be any number up to 4 billion. The area id identifies a logical grouping of routers.
area id is supplied as argument to the OSPF network id and mask command
Ex:
R1(config)#
router ospf 12345
R1(config-router)#
net 10.1.1.0 0.0.0.255 area 0
4. Where are EIGRP successor routes stored?
EIGRP succesor routers are stored in the routing table. The "succesor" is the successful or primary route.
The successor route is ALSO listed in the topology table,
The feasible successor is a BACKUP route and will ONLY be listed in the topology table, unless the successor route fails,
in which case the feasible successor would become the successor
Note that my EIGRP setup doesnt seem to folow this.
CTRL-F jump to "remotely connected via remote ingress ip address"
the book states that EIGRP is automatically load-balancing our two links from R1 to corp.. is this why there is no feasible successor here?
I did some research and found that in our case, we are not using a Feasible Successor. You CAN have two Successors with equal metric, in which case EIGRP will
automatically load-balance.
But I wanted to find out what a Feasible Successor actually looks like in the EIGRP topology table..
Kevin Wallace EIGRP article
Conclusion:
EIGRP topology table wouldnt specifically say "Feasible Successor", but you would know by two routes appearing, one with a lower metric.
In my topology we have two equal-metric links and they are both considered "Successors". EIGRP uses them equally (load-balanced)
Corp#
show ip eigrp toplogy
[cut]
P 172.16.10.0/24, 1 successors, FD is 28160
via 10.1.5.2 (28160/25600), FastEthernet0/0
P 192.168.10.0/24, 2 successors, FD is 2172416
via 10.1.3.2 (2172416/28160), Serial0/0/1
via 10.1.2.2 (2172416/28160), Serial0/0/0
P 192.168.20.0/24, 2 successors, FD is 2172416
via 10.1.3.2 (2172416/28160), Serial0/0/1
via 10.1.2.2 (2172416/28160), Serial0/0/0
P 192.168.30.0/24, 1 successors, FD is 2172416
via 10.1.4.2 (2172416/28160), Serial0/1/0
P 192.168.40.0/24, 1 successors, FD is 2172416
via 10.1.4.2 (2172416/28160), Serial0/1/0
5. Which command will display all the EIGRP feasible successor routes to a known router.
show ip eigrp topology
6. Find the configuration error. You type the following into your router, but dont see any routes in the routing table?
Router(config)#
router ospf 1
Router(config-router)#
network 10.0.0.0 255.0.0.0
wrong wildcard mask
instead, could have used
0.255.255.255
or
0.0.0.255
the point is we need to specify the first octet as "allowed" into our OSPF config with a 0 mask.
The remaining bits are 'dont care' bits aka 'wildcard' aka 255
7. Which three protocols support VLSM, summarization, and discontigous networking?
RIPv2
EIGRP
OSPF
all 3 build and mainting routing tables, provide classless routing which allows VLSM, summarization, and discontigous networks
RIPv1 and IGRP build/maintain routing tables, but dont offer classless routing
8. Which are true regarding OSPF areas?
the 'backbone' is area 0
if using other areas, they all must directly connect to area 0
9. Which two network types have a designated router and a backup designated router?
Broadcast
NBMA- Non broadcast multi access. Ex: Frame Relay
network types that DO NOT use DR/BDR:
point to point
broadcast multipoint
10. You need to configure a router with a distance-vector protocol that allows classless routing. Which to use?
EIGRP is considered 'advanced distance vector' (ripv2 wasnt an option)
11. You need the IP address of the devices with which the router has established an adjacency.
Also, the retransmit interval and the queue counts for the adjacent routers need to be checked. What command will display the required information?
show ip eigrp neighbors
WRONG: show ip eigrp adjacency - there is no such command.. the word 'adjacency' is only used with debug ip OSPF adjacency
here are the possible commands for show ip eigrp and debug ip eigrp
show ip eigrp ?
interfaces IP-EIGRP interfaces
neighbors IP-EIGRP neighbors
topology IP-EIGRP Topology Table
traffic IP-EIGRP Traffic Statistics
debug ip eigrp ?
summary IP-EIGRP summary route processing
12. You cant establish an adjacency relationship on a common ethernet link between two routers. Based on the output below, what is the cause of the problem?
RouterA#
Ethernet0/0 is up, line protocol is up
Internet Address 172.16.1.2/16, Area 0
Process ID 2, Router ID 172.126.1.2, Network Type BROADCAST, Cost: 10
Transmit Delay is 1 sec, State DR, Priority 1
Designated Router (ID) 172.16.1.2, interface address 172.16.1.1.
No backup designated router on this network
Timer intervals configured, Hello 5, Dead 20, Wait 20, Retransmit 5
Router B#
Internet Address 172.16.1.1/16, Area 0
Process ID 2, Router ID 172.126.1.1, Network Type BROADCAST, Cost: 10
Transmit Delay is 1 sec, State DR, Priority 1
Designated Router (ID) 172.16.1.1, interface address 172.16.1.2.
No backup designated router on this network
Timer intervals configured, Hello 10, Dead 40, Wait 40, Retransmit 5
mismatched timer intervals
OSPF default Hello is 10 and Dead is 40... RouterA was modified
13. Which is true regarding EIGRP successor routes?
Used in the routing table
also appears in the topolgy table
may (or may not) have a backup feasabile successor
14. Which type of OSPF network will elect a backup designated router?
broadcast multi-access
non-broadcast multiaccess
types of network that will NOT elect a BDR:
point to point and brodacast multipoint (hub/spoke topology)
15. Which two commands will place network 10.2.3.0/24 into area 0?
Router(config)#
router ospf 10
Router(config-router)#
network 10.2.3.0 0.0.0.255 area 0
16. With which network type will OSPF establish router adjacencies but not perform the DR/BDR election process?
Point to point
no election process occurs, there is never a DR on point to point
17. What are three reasons for creating OSPF in a heirarchical design?
decrease routing overhead
speed up convergence
confine stability to single areas of the network
18. What is the administrative distance of OSPF?
110
19.
no auto summary
the network is considered discontigous because we have two classful network subnetted (on the left and right),
seperated by a different classful address.
if auto summarization is taking place, the routers cant determine which side is which because both sides would be summarized as
Class B, 172.16.0.0, which isnt specific enough to distinguish between the sides.
20. IF routers in a single area are configured with the same priority value, what value does a router use for the OSPF router ID in the absence of a loopback interface?
The highest IP of any PHSYICAL interface.
Trick question. Highest IP of any LOGICAL interface is an option. And is correct IF you had logical interfaces, but the question
states that any "logical interfaces are absent".
At OSPF startup, the highest IP of *any* active interface on the router becomes the OSPF router ID. If you have loopback (logical) interfaces configured,
one of them (the largest IP) will *override* the phsyical interfaces and the loopback IP becomes the RID.
Reference for which loopback (if multiple) wins:
packetpushers.net
------------------------------------------------------------------------------
END CHAPTER 9
41 hours 2-14 thru 2-28-22
original total 184 hours
14 hours review 12-26 thru 12-28-22
review total hours 46
book page 502/822
184 + 46 = 230 hours * 60 = (13,800 min) / 500 pages =
avg 28 min/page (includes reading and exercises/labs + online research)
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1. Define the Cisco router componenets
ROM - used to start and maintain the router. Holds bootstrap, POST, mini-IOS
bootstrap - stored in the microcode of the ROM. Finds where the IOS program is located and loads the file.
POST - stored in the microcode of the ROM. Used to check the basic funtionality and determine which interfaces are present
ROM monitor - stored in the microcode of the ROM. Used for manufacturing, testing, and troubleshooting
mini-IOS - Called the RXBOOT or 'bootloader'. It's a small OS in ROM that can be used to bring up an interface and load a Cisco IOS into flash memory
-----------------------------------------------------------------------------------------------------------------------
flash memory - EEPROM- default location of the IOS
NVRAM -holds the router/switch configuration
not erased when the device is reloaded
configuration register - controls how the router boots up
Tells the router to load the IOS from flash memory as well as to load the configuration from NVRAM
RAM - used to hold packet buffers, ARP cache, routing tables and the data structures that allow the router to function.
running-config is stored in RAM
routers expand the IOS from flash into RAM at boot
2. Identify the steps in the router boot sequence
POST
bootstrap
load the IOS from flash into RAM
load the configuration file from NVRAM into RAM
running-config and the IOS are both now running in RAM
bootstrap
load the IOS from flash into RAM
load the configuration file from NVRAM into RAM
running-config and the IOS are both now running in RAM
3. Understand configuration register commands and settings
0x2102 default- find the boot sequence in NVRAM
0x2101 boot from ROM
0x2142 do not load the startup-config in NVRAM. Used for password recovery
0x2101 boot from ROM
0x2142 do not load the startup-config in NVRAM. Used for password recovery
4.Perform password recovery
NOTE - this requires physical access to reboot the router
NOTE - this requires physical access to reboot the router
The default configuration register value is 0x2102 which tells the router to load a config stored in NVRAM(startup-config).
To recover a password, we need to change the config register value to 0x2142 which tells the router to ignore the VRAM contents and load a 'non configured' OS.
"configurations" can be defined as any changes we make to the device: hostname, passwords, interfaces, etc
For this demo, our 4331 router is configured with the hostname 4331 and the password 1234
4331(config)# enable secret 1234
4331# copy run start
Destination filename [startup-config]?
Building configuration...
[OK]
Step 1. Bounce the router, then interrupt the boot sequence by performing a break.
Initializing Hardware ...
Checking for PCIe device presence...done
System integrity status: 0x610
Rom image verified correctly
System Bootstrap, Version 16.7(3r), RELEASE SOFTWARE
Copyright (c) 1994-2018 by cisco Systems, Inc.
Current image running: Boot ROM0
Last reset cause: LocalSoft
Cisco ISR4331/K9 platform with 4194304 Kbytes of main memory
no valid BOOT image found
Final autoboot attempt from default boot device...
Located isr4300-universalk9.16.06.04.SPA.bin
###############################################################
CTRL+BREAK
monitor: command "boot" aborted due to user interrupt
rommon 1 >
Step 2. We're given a ROM MONITOR prompt which allows us to change the configuration register (Cisco ISR/2600 Series commands).
rommon 1 > confreg 0x2142
rommon 1 > reset must reset or power cycle router to apply the change
system will ask if you want Setup Mode - that is the the generic startup message, since we are bypassing the startup configuration. Our answer is no.
--- System Configuration Dialog ---
Would you like to enter the initial configuration dialog? [yes/no]:
N + Enter
we now have full access to this non-configured OS. We can enter priviliged mode with no password.
Router> enable
Router# show version
Cisco IOS Software [Everest], ISR Software (X86_64_LINUX_IOSD-UNIVERSALK9-M), Version 16.6.4,RELEASE SOFTWARE (fc3)
[cut]
Configuration register is 0x2142
this verifies that our configs are not in use (no hostname in the prompt) and our config register has been changed to 2142
HERE IS THE KEY-
we are going to restore the configuration by copying the "startup-config" into our live environment AKA the "running-config"
Router# copy startup-config running-config
Destination filename [running-config]? Enter
695 bytes copied in 0.416 secs (1670 bytes/sec)
4331#
%SYS-5-CONFIG_I: Configured from console by console
we get our old prompt back:
4331#
Note that we DO NOT know the password required to enter privliged mode that we are currently inside of!
if you exit this prompt back out to user mode, you will not be able to get back in without the password.
We entered privileged mode from within the generic configuration. Then inserted our saved configuration 'beneath' our prompt. This action does not kick you out of priv. mode, which will allow us to RESET the password for our saved configuration.
set the new password
4331(config)# enable secret 0000
set the config register back to default, to point back to NVRAM on the next reboot (you can do this from global config mode as well as rommon mode)
4331(config)# config-register 0x2102
4331# show version
[cut]
Configuration register is 0x2142 (will be 0x2102 at next reload)
now we can save the config with the updated password.
Two ways to do it-
4331# write
Building configuration...
[OK]
OR
4331# copy running-config startup-config
Destination filename [startup-config]?
Building configuration...
[OK]
reload the router and your new password will be saved into your config
4331# reload
5. Back up an IOS image
we can copy a router's configuration to a TFTP server with either of these commands:
Router# copy running-config tftp
Router# copy startup-config tftp
to verify either of the configs before backup, we can use these commands:
Router# show running-config
Router# show startup-config
Router# copy running-config tftp
Router# copy startup-config tftp
to verify either of the configs before backup, we can use these commands:
Router# show running-config
Router# show startup-config
6. Restore or upgrade an IOS image - note we are talking about the IOS itself, not the 'configuration'
We will download the IOS file from TFTP server to flash memory on the router. Command requires the IP of the TFTP host and the filename
Before we begin we must make sure the IOS file is in the default TFTP directory on the host.
The command will not ask you where the file is on the host....
Router# copy tftp flash
to restore configuration:
We will download the IOS file from TFTP server to flash memory on the router. Command requires the IP of the TFTP host and the filename
Before we begin we must make sure the IOS file is in the default TFTP directory on the host.
The command will not ask you where the file is on the host....
Router# copy tftp flash
Address or name of remote host []? 1.1.1.2
Source filename []? c2800nm-advsecurityk9-mz.124.12.bin
Destination filename[c2800nm-advsecurityk9-mz.124.12.bin]? ENTER
%Warning this is a file already existing with this name
Do you want to over write [confirm] ENTER
Accessing tftp://1.1.1.2/c2800nm-advsecurityk9-mz.124-12.bin...
Loading c2800nm-advsecurityk9-mz.124-12.bin from 1.1.1.2 (via FastEthernet0/0): !!!!!!!!!!!!!!!!
!!!!!!!!!!!!!!!!!!!!!!!!!!
[OK - 21710744 bytes]
21710744 bytes copied in 82.880 secs (261954 bytes/sec)
Router#
to restore configuration:
restore from startup-config:
Router# copy startup-config running-config
or we can restore from a backup on TFTP server
Router# copy tftp running-config
Router# copy startup-config running-config
or we can restore from a backup on TFTP server
Router# copy tftp running-config
Address or name of remote host []? 1.1.1.2
Source filename []? todd-confg
Destination filename[running-config?] ENTER
Accessing tftp://1.1.1.2/todd-confg...
Loading todd-confg from 1.1.12 (civa FastEthernet0/0): !
[OK - 776 bytes]
776 bytes copied in 9.212 secs (84 bytes/sec)
Router#
*Jan 23 12:40:00.000: %SYS-5-CONFIG_I: Configured from tftp://1.1.1.2/todd-confg by console
Router#
7. Describe best practices to prepare to back up an IOS image to a network server
Ensure you can acccess the network server, and there is adequate storage space.
Verify the file naming and path requirements
have the source IOS file in the default TFTP directory
Verify the file naming and path requirements
have the source IOS file in the default TFTP directory
8. Save the configuration of a router
Router#
copy running-config startup-config
9. Erase the configuration of a router
Router#
erase startup-config
10. Understand and use the Cisco IFS file system management commands
IFS = IOS File System
UNIX Based
dir
show files in a directory. Requires privliged mode. If not path is given as argument, you'll see the directory of 'flash' root.
NOTE the file paths use a URL format
R1# dir
-------------------------------------------------------------------------------------------------------
copy
often used to backup, restore, or ugprade the IOS
first arg = source
second arg = destination
R1# copy source destination
-------------------------------------------------------------------------------------------------------
more
display a text file
-------------------------------------------------------------------------------------------------------
show file
display a text file
-------------------------------------------------------------------------------------------------------
delete
remote file (may also need to use SQUEEZE to free up the space)
-------------------------------------------------------------------------------------------------------
erase/format
may delete flash drive depending on system
-------------------------------------------------------------------------------------------------------
cd/pwd
change directory / print working directory
-------------------------------------------------------------------------------------------------------
mkdir/rmdir
create / delete directories
UNIX Based
dir
show files in a directory. Requires privliged mode. If not path is given as argument, you'll see the directory of 'flash' root.
NOTE the file paths use a URL format
R1# dir
Directory of flash:/
3 -rw- 486899872 <no date> isr4300-universalk9.16.06.04.SPA.bin
2 -rw- 28282 <no date> sigdef-category.xml
1 -rw- 227537 <no date> sigdef-default.xml
3249049600 bytes total (2761893909 bytes free)
-------------------------------------------------------------------------------------------------------
copy
often used to backup, restore, or ugprade the IOS
first arg = source
second arg = destination
R1# copy source destination
-------------------------------------------------------------------------------------------------------
more
display a text file
-------------------------------------------------------------------------------------------------------
show file
display a text file
-------------------------------------------------------------------------------------------------------
delete
remote file (may also need to use SQUEEZE to free up the space)
-------------------------------------------------------------------------------------------------------
erase/format
may delete flash drive depending on system
-------------------------------------------------------------------------------------------------------
cd/pwd
change directory / print working directory
-------------------------------------------------------------------------------------------------------
mkdir/rmdir
create / delete directories
11. Describe the value of CDP
Cisco Discovery Protocol - helps to document / troubleshoot the network
See lab 7.4
See lab 7.4
12. List the information provided by the output of
show cdp neighbors
device ID
local interface
holdtime
capabilility
platform
port ID (remote interface)
local interface
holdtime
capabilility
platform
port ID (remote interface)
13. Understand how to establish a Telnet session with multiple routers simultaneously
Press Ctrl+Shift+6 then x to exit a telnet session without closing it
14. Identify current Telnet sessions
R1#
show sessions
15. Build a static host table on a router
R1#
ip host
host_name
ip_address
manually assigning an IP to a host name. You can apply multiple IP's to one host entry
see lab 7.6
manually assigning an IP to a host name. You can apply multiple IP's to one host entry
see lab 7.6
16. Verify the host table on a router
R1#
show hosts
17. Describe the function of the ping command
Packet Internet Groper uses ICMP echo requests and replies to verify an active IP address on a network
18. Ping a vaild host ID from the correct prompt
R1#
ping 1.1.1.1
Note PING works from user or privliged mode but NOT config mode
Note PING works from user or privliged mode but NOT config mode
TFTP Server Setup - network layout is not from book- I created this network to help demo the written lab
TFTP server is already created and switched on by default within the 'Server' object
Router Configuration
R1(config)# int g0/0/1
R1(config-if)# ip address 10.1.1.4 255.255.255.0
R1(config-if)# no shutdown
%LINK-5-CHANGED: Interface GigabitEthernet0/0/1, changed state to up
%LINEPROTO-5-UPDOWN: Line protocol on Interface GigabitEthernet0/0/1, changed state to up
r1(config-if)#
do show ip int brief
Interface IP-Address OK? Method Status Protocol
GigabitEthernet0/0/0 unassigned YES manual administratively down down
GigabitEthernet0/0/1 192.1.1.4 YES NVRAM up up
GigabitEthernet0/0/2 unassigned YES NVRAM administratively down down
Vlan1 unassigned YES NVRAM administratively down down
Switch Configuration
SW1(config)# int f0/1
SW1(config-if)# no shutdown
%LINK-5-CHANGED: Interface FastEthernet0/1, changed state to up
%LINEPROTO-5-UPDOWN: Line protocol on Interface FastEthernet0/1, changed state to up
SW1(config-if)# int f0/2
SW1(config-if)# no shutdown
%LINK-5-CHANGED: Interface FastEthernet0/2, changed state to up
%LINEPROTO-5-UPDOWN: Line protocol on Interface FastEthernet0/2, changed state to up
Test connectivity to the server
R1# ping 192.1.1.3
Type escape sequence to abort.
Sending 5, 100-byte ICMP Echos to 192.1.1.3, timeout is 2 seconds:
.!!!!
Success rate is 80 percent (4/5), round-trip min/avg/max = 0/1/6 ms
Find the name of the Router flash file
R1# show flash
System flash directory:
File Length Name/status
3 486899872isr4300-universalk9.16.06.04.SPA.bin
2 28282 sigdef-category.xml
1 227537 sigdef-default.xml
[487155691 bytes used, 2761893909 available, 3249049600 total]
3.17338e+06K bytes of processor board System flash (Read/Write)
we need to paste that filename into our copy command below
1. command to copy a Cisco IOS to a TFTP server?
R1#
copy flash tftp
the file appears on our server
Source filename []? isr4300-universalk9.16.06.04.SPA.bin
Address or name of remote host []? 192.1.1.3
Destination filename [isr4300-universalk9.16.06.04.SPA.bin]? ENTER
Writing isr4300-universalk9.16.06.04.SPA.bin...!!!!!!!!!!!!!!!!
!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!
[OK - 486899872 bytes]
486899872 bytes copied in 12.364 secs (126865 bytes/sec)
the file appears on our server
2. command to copy a Cisco startup-config file to a TFTP server?
R1#
copy running-config tftp
the file appears on our server
OR
R1# copy startup-config tftp
Address or name of remote host []? 192.1.1.3
Destination filename [r1-confg]? ENTER
Writing running-config.....!!
[OK - 707 bytes]
707 bytes copied in 3 secs (235 bytes/sec)
the file appears on our server
OR
R1# copy startup-config tftp
3. command to copy the startup-config file to DRAM?
R1#
copy startup-config running-config
the running configuration exists in DRAM
the running configuration exists in DRAM
4. What is an older command that you can use to copy the startup-config file to DRAM?
R1#
config mem
(not supported by packet tracer)
(not supported by packet tracer)
5. What command can you use to see the neighbor router's IP address from your router prompt?
R1#
show cdp neighbor detail
OR
R1# show cdp entry *
OR
R1# show cdp entry *
6. What command to see the hostname, local interface, platform, and remote port of a neighbor router?
R1#
show cdp neighbor
7. What keystrokes can you use to telnet into multiple devices simultaneously?
Ctrl + Shift + 6, then X
8. What command will show you your active Telnet connections to neighbor and remote devices?
R1#
show sessions
9. What command can you use to upgrade a Cisco IOS?
R1#
copy tftp flash
10. What command can you use to merge a backup configuration with the configuration in RAM?
R1#
copy tftp run
OR
R1# copy start run
RAM = running configuration
OR
R1# copy start run
RAM = running configuration
Chapter 7 Written Lab 7.2 - Router Memory
Identify the location in a router where each of the files is stored by default:
1. Cisco IOS
flash
2. Bootstrap
ROM
3. Startup configuration
NVRAM
4. POST
ROM
5. Running configuration
RAM
6. ARP cache
RAM
7. Mini IOS
ROM
8. ROM Monitor
ROM
9. Routing tables
RAM
10. packet buffers
RAM
****dont make the mistake of thinking arp cache, routing tables, packet buffers, are stored somewhere other than RAM
they are considered part of running-config which exists in RAM
Chapter 7 Hands-on Labs
To complete these labs, we are going to need three routers and one TFTP server.
Here is the topology:
Server Configuration
ipv4 address: 193.1.1.2
subnet mask: 255.255.255.248
default gateway: 193.1.1.1
Switch Configuration
SW1#
interface range f0/1-2
SW1(config-if-range)#
no shut
Router Configurations
R1(config)#
int g0/0/0
R1(config)#
ip addr 193.1.1.9 255.255.255.248
R1(config)#
no shut
R1(config)#
int g0/0/1
R1(config)#
ip addr 193.1.1.1 255.255.255.248
R1(config)#
no shut
the server's default gateway
R2(config)#
int g0/0/0
R2(config)#
ip addr 193.1.1.10 255.255.255.248
R2(config)#
no shut
R2(config)#
int g0/0/1
R2(config)#
ip addr 193.1.1.17 255.255.255.248
R2(config)#
no shut
R3(config)#
int g0/0/0
R3(config)#
ip addr 193.1.1.18 255.255.255.248
R3(config)#
no shut
the segment between R1 and the server
network 193.1.1.0/29
block of 8
hosts .1, .2
the segment between R1 and R2
network 193.1.1.8/29
block of 8
hosts .9 , .10
the segment between the R2 and R3
network 193.1.1.16/29
block of 8
hosts .17 , .18
THIS IS INCORRECT!!!!
I have misunderstood the instructions.
the problem with this topology is that packets cannot pass through the routers. We dont have any ROUTING setup. ROUTING is covered in the next chapter.
For these labs, we dont need routing, but we need multiple routers to demo telnet and CDP. Here are the instructions:
my mistake was not putting all router interfaces in the same subnet. I tried to do this initially, but it wouldnt work because I had the routers linked together rather than connected by a switch.
The instructions say:
"Your PC and the router(s) are connected together with a switch"
this is the part I missed. The pc and all router interfaces should be on the same switch and the same network
Here is the corrected topology
Server Configuration
ipv4 address: 193.1.1.4
subnet mask: 255.255.255.248
default gateway: 193.1.1.1
Switch Configuration
SW1#
interface range f0/1-4
SW1(config-if-range)#
no shut
Router Configurations
R1(config)#
int g0/0/0
R1(config)#
ip addr 193.1.1.1 255.255.255.248
R1(config)#
no shut
the server's default gateway
R2(config)#
int g0/0/0
R2(config)#
ip addr 193.1.1.2 255.255.255.248
R2(config)#
no shut
R3(config)#
int g0/0/0
R3(config)#
ip addr 193.1.1.3 255.255.255.248
R3(config)#
no shut
Chapter 7 Hands-on Lab 7.1 Backing up your router IOS
1. verify connection to the server
R1#
ping 193.1.1.1
Type escape sequence to abort.
Sending 5, 100-byte ICMP Echos to 193.1.1.2, timeout is 2 seconds:
.!!!!
Success rate is 80 percent (4/5), round-trip min/avg/max = 0/1/5 ms
2. show contents of flash memory
R1#
show flash
System flash directory:
File Length Name/status
3 486899872isr4300-universalk9.16.06.04.SPA.bin
2 28282 sigdef-category.xml
1 227537 sigdef-default.xml
[487155691 bytes used, 2761893909 available, 3249049600 total]
3.17338e+06K bytes of processor board System flash (Read/Write)
show flash gives ALL of the files in flash memory
show version gives the current running file
3. show the IOS currently running
R1#
show version
Cisco IOS XE Software, Version 03.16.05.S - Extended Support Release
[cut]
ROM: IOS-XE ROMMON
Router uptime is 9 minutes, 39 seconds
Uptime for this control processor is 9 minutes, 39 seconds
System returned to ROM by power-on
System image file is "bootflash:/isr4300-universalk9.03.16.05.S.155-3.S5-ext.SPA.bin"
Last reload reason: PowerOn
[cut]
note that the file that is currently running is NOT located in the flash storage!!!
4. backup IOS from router to server
R1#
copy flash tftp
Source filename []?isr4300-universalk9.16.06.04.SPA.bin
Address or name of remote host []? 193.1.1.4
Destination filename [isr4300-universalk9.16.06.04.SPA.bin]? ENTER
Writing isr4300-universalk9.16.06.04.SPA.bin...!!!!!!!!!!!!!!!
[OK - 486899872 bytes]
486899872 bytes copied in 12.526 secs (125224 bytes/sec)
Chapter 7 Hands-on Lab 7.2 Upgrading or restoring your router IOS
1. verify connection to the server
R1#
ping 193.1.1.4
Type escape sequence to abort.
Sending 5, 100-byte ICMP Echos to 193.1.1.2, timeout is 2 seconds:
!!!!!
Success rate is 100 percent (5/5), round-trip min/avg/max = 0/0/1 ms
2. copy from tftp sever to flash
R1#
copy tftp flash TFTP comes first in the command since we are pulling from TFTP server.
In this command, remot host address is required before file name
Address or name of remote host []? 193.1.1.4
Source filename []?isr4300-universalk9.16.06.04.SPA.bin
Destination filename [isr4300-universalk9.16.06.04.SPA.bin]? ENTER
%Warning:There is a file already existing with this name
Do you want to over write? [confirm]
Accessing tftp://193.1.1.4/isr4300-universalk9.16.06.04.SPA-12-23-22...
Loading isr4300-universalk9.16.06.04.SPA-12-23-22.bin from 193.1.1.4: !!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!
[OK - 486899872 bytes]
486899872 bytes copied in 12.785 secs (122688 bytes/sec)
Chapter 7 Hands-on Lab 7.3 Backing up the router configuration
1. verify connection to the server
R1#
ping 193.1.1.2
Type escape sequence to abort.
Sending 5, 100-byte ICMP Echos to 193.1.1.4, timeout is 2 seconds:
!!!!!
Success rate is 100 percent (5/5), round-trip min/avg/max = 0/0/1 ms
2. copy running-confing to server
R1#
copy run tftp
Address or name of remote host []? 193.1.1.4
Destination filename [R1-confg]?ENTER "R1-confg" is the default name
Writing running-config...!!
[OK - 668 bytes]
668 bytes copied in 0.004 secs (167000 bytes/sec)
Chapter 7 Hands-on Lab 7.4 Using the Cisco Discovery Protocol (CDP)
R1#
show cdp
Global CDP information:
Sending CDP packets every 60 seconds
Sending a holdtime value of 180 seconds
Sending CDPv2 advertisements is enabled
R1#
show cdp interface
Vlan1 is administratively down, line protocol is down
Sending CDP packets every 60 seconds
Holdtime is 180 seconds
GigabitEthernet0/0/0 is up, line protocol is up
Sending CDP packets every 60 seconds
Holdtime is 180 seconds
GigabitEthernet0/0/1 is administratively down, line protocol is down
Sending CDP packets every 60 seconds
Holdtime is 180 seconds
GigabitEthernet0/0/2 is administratively down, line protocol is down
Sending CDP packets every 60 seconds
Holdtime is 180 seconds
R1#
show cdp entry *
Device ID: SW1
Entry address(es):
Platform: cisco 2960, Capabilities: Switch
Interface: GigabitEthernet0/0/0, Port ID (outgoing port): FastEthernet0/1
NOTE g0/0/0 is the outgoing port on this router, F0/1 is the port on the switch at other end
Holdtime: 157
Version :
Cisco IOS Software, C2960 Software (C2960-LANBASEK9-M), Version 15.0(2)SE4, RELEASE SOFTWARE (fc1)
Technical Support: http://www.cisco.com/techsupport
Copyright (c) 1986-2013 by Cisco Systems, Inc.
Compiled Wed 26-Jun-13 02:49 by mnguyen
advertisement version: 2
Duplex: full
R1#
show cdp entry neighbors
[no output]
R1#
show cdp neighbors detail
Device ID: SW1
Entry address(es):
Platform: cisco 2960, Capabilities: Switch
Interface: GigabitEthernet0/0/0, Port ID (outgoing port): FastEthernet0/1
Holdtime: 178
Version :
Cisco IOS Software, C2960 Software (C2960-LANBASEK9-M), Version 15.0(2)SE4, RELEASE SOFTWARE (fc1)
Technical Support: http://www.cisco.com/techsupport
Copyright (c) 1986-2013 by Cisco Systems, Inc.
Compiled Wed 26-Jun-13 02:49 by mnguyen
advertisement version: 2
Duplex: full
Chapter 7 Hands-on Lab 7.5 Using Telnet
enable telnet on R2 and set password
R2(config)#
line vty 0 15
R2(config-line)#
password telnet
R2(config-line)#
login
enable telnet on R3 and set password
R3(config)#
line vty 0 15
R3(config-line)#
password telnet
R3(config-line)#
login
note that the result of this command on each router, by default,
is to present all 15 lines in TWO SEPERATE chunks: 0-4 and 5-15
R3#
show run
[cut]
!
!
!
line con 0
!
line aux 0
!
line vty 0 4
password telnet
login
line vty 5 15
password telnet
login
!
!
!
end
--------------------------------------------------------------------------------
connect to R2 from R1
R1#
telnet 193.1.1.2
Trying 193.1.1..2 ...Open
User Access Verification
Password: telnet
prompt changes to R2 to indicate we are remoted in
R2>
exit the session
ctrl + shift + 6, x
prompt changes back to R1
R1#
--------------------------------------------------------------------------------
connect to R3 from R1
R1#
193.1.1.3 note that the word 'telnet' is not required bc we are still in telnet mode
Trying 193.1.1..3 ...Open
User Access Verification
Password: telnet
prompt changes to R3 to indicate we are remoted in
R3>
exit the session
ctrl + shift + 6, x
prompt changes back to R1
R1#
--------------------------------------------------------------------------------
We have exited the sessions, but they are still open
R1#
show sessions
Conn Host Address Byte Idle Conn Name
1 193.1.1.2 193.1.1.2 0 0 193.1.1.2
* 2 193.1.1.3 193.1.1.3 0 0 193.1.1.3
two telnet sessions- notice that the 'conn number' doesnt correspond to ip address in any way.
R1#
show users
Line User Host(s) Idle Location
* 0 con 0 193.1.1.2 00:00:03
193.1.1.3 00:00:43
this is saying one user is on this router, with two outbound connections (but it isnt showing that they are vty connections)
... they must both be considered 'console' connections outbound and are not considered 'vty' until they are received inbound
the asterisk means something different here than above... doesnt mean default(most recent)session... what does it mean?
back to R2
R2#
show users
Line User Host(s) Idle Location
* 4 vty 0 idle 00:00:00 193.1.1.1
Interface User Mode Idle Peer Address
this is saying that there is one (unnamed) user remoted in via line vty 4
back to R3
R3#
show users
Line User Host(s) Idle Location
* 4 vty 0 idle 00:00:00 193.1.1.1
Interface User Mode Idle Peer Address
this is saying that there is one (unnamed) user remoted in via line vty 4
-------------------------------------------------------------------------------------
Important Considerations:
-
asterisk indicates default session
-
when telnetting in, you will be in user mode. If there is no password already set for PRIVILEGED MODE, you will be unable to enter
-
be careful with 'exit'. it will exit the telnet session if you exit at priv. mode. Use 'disable' to leave priv mode.
-
after 'suspending' a session with ctrl+shift+6,x and youre back at your original priv. prompt, do not press enter to create line breaks-
rather than break lines as usual, the keystroke will cause this:
[Resuming connection 1 to 193.1.1.2 ... ]
prompt will sit here until you strike enter again, then you'll return to that session. What is actually happening is that
youre connecting to the 'default' telnet connection. The same behavior happens when youre at the 'show sessions' screen.
Even if you are not viewing active sessions, the enter key(twice) will connect you to the default session
-
you can use disconnect or exit to end a session
-
Ex: disconnect 1 at the show sessions screen
Chapter 7 Hands-on Lab 7.6 Resolving Hostnames
We're going to build a host table on R1 so we can connect to the other routers via hostname rather than type in the IP address
the command is ip host name arg ip arg
R1(config)#
ip host R2 193.1.1.2
R1(config)#
ip host R3 193.1.1.3
Now if we enter R2 or telnet R2 we get the telnet prompt
R1# R2
Trying 193.1.1.2 ...Open
User Access Verification
Password:
same for the PING command
R1# ping R2
Type escape sequence to abort.
Sending 5, 100-byte ICMP Echos to 193.1.1.2, timeout is 2 seconds:
!!!!!
Success rate is 100 percent (5/5), round-trip min/avg/max = 0/0/2 ms
R1#
show hosts
Default Domain is not set
Name/address lookup uses domain service
Name servers are 255.255.255.255
Codes: UN - unknown, EX - expired, OK - OK, ?? - revalidate
temp - temporary, perm - permanent
NA - Not Applicable None - Not defined
Host Port Flags Age Type Address(es)
R2 None (perm, OK) 0 IP 193.1.1.2
R3 None (perm, OK) 0 IP 193.1.1.3
R1#
telnet R2
R2>
CTRL + SHIFT + 6, X
R1#
telnet R3
R3>
CTRL + SHIFT + 6, X
R1#
show session
Conn Host Address Byte Idle Conn Name
1 R2 193.1.1.2 0 0 R2
* 2 R3 193.1.1.3 0 0 R3
Chapter 7 Review Questions
1. What does the command
confreg 0x2142
provide?
bypass startup-config, to allow password reset
2. Which command will copy the IOS to a backup host on your network?
copy flash tftp
3. You are troubleshooting a connectivity problem in your corporate network and want to isolate the problem. You suspect that a router on the route to an unreachable
network is at fault. What IOS user exec command should you issue?
traceroute
note this is not a priviliged mode command; it can be run from user mode
4. You copy a configuration from a network host to a router's RAM. The configuration looks correct, yet it is no working at all. What could the problem be?
when you perform a copy from a network host to a router, the interfaces are automatically shut down and have to be manually enabled with no shutdown
5. A network administrator wants to upgrade the IOS of a router without removing the image currently installed. What command will display the amount of memory consumed by the
current IOS image and indicate whether there is enough room available to hold both the current and new images?
show flash
6. The corporate office sends you a new router to connect, but upon connecting the console cable, you see that there is already a configuration on the router.
What should be done before a new configuration is entered in the router?
erase NVRAM and restart the router
erase startup-config
reload
7. Which command loads a new version of the Cisco IOS into a router?
copy tftp flash
8. Which command will show you the IOS version running on your router?
show version
9. What should the configuration register value be after you successfully complete the password recovery procedure and return the router to normal operation?
0x2102
10. You save the configuration on a router with the
copy running-config startup-config
command and reboot the router. The router, however, comes up with a blank configuration. What can the problem be?
wrong config register causing you to bypass startup-confing in NVRAM
11. If you want to have more than one Telnet session open at the same time, what keystroke combination would you use?
CTRL+SHIFT+6, X
12. You are unsuccessful in telnetting into a remote device, but you could telnet to the router earlier, However, you can still ping the remote device.
What can the problem be?
access control list could be filtering telnet
OR
the VTY password may not be set on the target
13. What information is displayed by the
show hosts
command?
gives info on temporary DNS entries and permanent name-to-address mappings created using the ip host command
14. Name three commands that can be used to check LAN connectivity problems on a router?
trace
show interfaces
show ip route
15. You telnet to a router and make your necessary changes; now you want to end the Telnet session. What command do you type in?
exit
16. You telnet into a remote device and type
debug ip rip
but no output from the
debug
command is seen. What could the problem be?
to see console messages through a telnet session, you must enter the command terminal monitor
17. Which command displays the configuration register setting?
show version
18. You need to gather the IP address of a remote switch that is located in Hawaii. What can you do to find the address?
show cdp neighbors detail
19. You have your laptop directly connected into a router's Ethernet port. Which are requirements for the
copy flash tftp
command to be successful?
have a TFTP server running on the laptop
laptop must have an IP on the same subnet as the router interface
give the IP address of the laptop when asked after entering the command
20. The configuration register setting of 0x2102 provides what function to a router?
points to NVRAM for startup-configuration AND boot sequence
END CHAPTER 7
26 hours 1-19 thru 1-26-22
original total hours 89
7 hours review 12-23-22
review total hours 20.5
book page 344/822
avg 15 min/page (reading and exercises/labs)
Chapter 8 Exercises
pg 374
before I begin to configure this network, I want to look closer at the HARDWARE
Todd mentions these routers:
2811 with four serial interfaces and switch module or wireless card
1841
while the book was published in 2011, both routers appear to be available in 2021 packet tracer,
but both are considered legacy as of Feb 2022.
The 2811:
The 1841:
we're going to need to understand the MODULES. What are these?
a few examples:
NM-1E is a 1-port ethernet module
NM-1FE-TX is a fast ethernet module
NM-8A/s is an Eight Port Async/Sync Network Module
HWIC-2T is a 2-port serial WAN interface card
HWIC-AP-AG-B is a wireless card
What is an "NM module"?
A network module is a software module that implements a specific
function in a network stack, such as a data link interface, a transport protocol,
or a network application.
What is a "HWIC module"?
A high-speed WAN interface card
Here is a look inside a real 2811:
Back to the requirements for our lab- Todd says the 2811 'Corp' router needs a switch module
and four serial interfaces. NOTE the book doesnt give specifics on how to create the topology in Packet Tracer.
Our Packet Tracer 2811 offers these modules:
The NM-ESW-16 appears to be the only 'switch module', so I will add that.
And the HWIC-2T is a 2-Port Serial High-Speed WAN Interface Card, providing 2 serial ports.
I will add two of these.
next: R3, which needs to be a 2811 with a wirless card. I will add the HWIC-AP-AG-B:
The HWIC-AP-AG-B module is a High-Speed WAN Interface Card providing integrated Access Point
functionality in the Cisco 1800 (Modular), Cisco 2800,
and Cisco 3800 Integrated Services Routers.
It supports Single Band 802.11b/g or Dual Band 802.11a/b/g radios.
our router hardware is in place:
and here is where we need to end up
Next we need to figure out how to connect the server farm to the switch card on R1:
if I use the auto-select cable, I get a copper crossover cable connecting at fa0/0 on the router.
Per the diagram fa0/0 should
connect to R3. I need to connect the servers to the switch card on R1.
Instead of using the auto-select cable, I'll try a straight-through cable.
Success. While the auto-select cable did not give me an option as to what port it will connect to, I did get the option when
manually applying the straight-through cable. Instead of connecting to F0/0 which would require a crossover-cable(computer to router),
I will connect to the integrated switch at port F1/0, then connect the other two servers to F1/1 and F1/2, respectively.
Also worth noting: the Physical Device diagrams in Packet Tracer do not show cables plugged into the ports.
We are relying on the labels on the logical diagram to see which cables are plugged into which ports...
As far as how we can tell what is connected from within the CLI.. I dont know right now.
Now I will connect the other routers. Here is the chart specifiying what interfaces should be used:
Router
Network Address
Interface
Address
CORP
10.1.1.0
Vlan1 (switch card)
10.1.1.1
10.1.2.0
S0/0/0
10.1.2.1
10.1.3.0
S0/0/1 (DCE)
10.1.3.1
10.1.4.0
S0/1/0
10.1.4.1
10.1.5.0
F0/0
10.1.5.1
R1
10.1.2.0
S0/0/0 (DCE)
10.1.2.2
10.1.3.0
S0/0/1
10.1.3.2
192.168.10.0
F0/0
192.168.10.1
192.168.20.0
F0/1
192.168.20.1
R2
10.1.4.0
S0/0/0 (DCE)
10.1.4.2
192.168.30.0
F0/0
192.168.30.1
192.168.40.0
F0/0
192.168.40.1
R3
10.1.5.0
F0/0
10.1.5.2
172.16.10.0
Dot11Radio0/0/0
172.16.10.1
PROBLEM
The R1 router doesnt appear to have any serial interfaces
I will add an HWIC-2T card to both R1 and R2 since the diagram calls for serial interfaces.
The HWIC-2T is a Cisco 2-Port Serial High-Speed WAN Interface Card, providing 2 serial ports.
PROBLEM
The Corp router is not showing the expected available interfaces. I need to connect R1 to the S0/0/0 interface on Corp and R2 to the S0/0/1 interface on Corp.
My Corp router is not showing those interfaces:
Solution
the placement of the cards on the router determines which interface numbers will be available.
In this case, it seems the interfaces start from the bottom right corner and increase on each slot moving clockwise. I found this out by filling all four slots on my router
which led to all interfaces being available. I then ran a card in each slot individually to isolate which interface numbers correspond to each slot:
Interestingly, while the physical slots seem to follow a 'clockwise' pattern, the list of available slots in the logical diagram does not;
We get an output of interfaces corresponding to slot 2, then 3, 1, and 4. This is a 'bottom to top' then 'left to right' pattern. Tricky.
Having said all that... I will run cards in slots 1 and 2 for this lab since we only need interfaces S0/0/0, S0/0/1, S0/1/0
The Router topology:
I'm not clear on the connections from R1 and R2 to the clients.. I assume there are switches involved.
For now I will follow the next steps in the book which
are to configure the corp router as follows:
Router(config)#
hostname Corp
Corp(config)#
enable secret todd
Corp(config)#
interface vlan 1
Corp(config-if)#
description Switch Card to Core Network
Corp(config-if)#
ip address 10.1.1.1 255.255.255.0
Corp(config-if)#
no shut
----------------------------------------------------------------------------------------------------------------
Corp(config-if)#
int f1/0
Corp(config-if)#
description Switch Port connection to WWW Server
Corp(config-if)#
no shutdown
Corp(config-if)#
int f1/1
Corp(config-if)#
description Switch Port connection to Email Server
Corp(config-if)#
no shutdown
Corp(config-if)#
int f1/2
Corp(config-if)#
description Switch Port connection to DNS Server
Corp(config-if)#
no shutdown
----------------------------------------------------------------------------------------------------------------
Corp(config-if)#
int s0/0/0
Corp(config-if)#
description 1st Connection to R1
Corp(config-if)#
ip address 10.1.2.1 255.255.255.0
Corp(config-if)#
no shut
Corp(config-if)#
int s0/0/1
Corp(config-if)#
description 2nd Connection to R1
Corp(config-if)#
ip address 10.1.3.1 255.255.255.0
Corp(config-if)#
no shut
Corp(config-if)#
int s0/1/0
Corp(config-if)#
description Connection to R2
Corp(config-if)#
ip address 10.1.4.1 255.255.255.0
Corp(config-if)#
no shut
Corp(config-if)#
int fa0/0
Corp(config-if)#
description Connection to R3
Corp(config-if)#
ip address 10.1.5.1 255.255.255.0
Corp(config-if)#
no shut
----------------------------------------------------------------------------------------------------------------
Corp(config-if)#
line con 0
Corp(config-if)#
password console
Corp(config-if)#
login
Corp(config-if)#
logging synchro
Corp(config-if)#
exec-timeout 0 0
----------------------------------------------------------------------------------------------------------------
Corp(config-if)#
line aux 0
Corp(config-if)#
password aux
Corp(config-if)#
login
Corp(config-if)#
exit
----------------------------------------------------------------------------------------------------------------
Corp(config)#
line vty ?
<1-15>Last Line number
Corp(config)#
line vty 0 15
Corp(config-if)#
password telnet
Corp(config-if)#
login
Corp(config-if)#
exit
----------------------------------------------------------------------------------------------------------------
Corp(config)#
no ip domain lookup
Corp(config)#
banner motd # This is my Corp 2811 ISR Router #
Ctrl + Z
%SYS-5-CONFIG_I: Configured from console by console
(Ctrl-Z: When in a config mode, ends the config mode and returns you to privileged EXEC mode.... same as typing exit(?))
Corp#
copy run start
Destination filename [startup-config]?
Building configuration...
[OK]
----------------------------------------------------------------------------------------------------------------
Corp#
show ip int br
Interface IP-Address OK? Method Status Protocol
FastEthernet0/0 10.1.5.1 YES manual up down
FastEthernet0/1 unassigned YES unset administratively down down
Serial0/0/0 10.1.2.1 YES manual down down
Serial0/0/1 10.1.3.1 YES manual down down
Serial0/1/0 10.1.4.1 YES manual down down
Serial0/1/1 unassigned YES unset administratively down down
FastEthernet1/0 unassigned YES unset up up
FastEthernet1/1 unassigned YES unset up up
FastEthernet1/2 unassigned YES unset up up
FastEthernet1/3 unassigned YES unset administratively down down
FastEthernet1/4 unassigned YES unset administratively down down
FastEthernet1/5 unassigned YES unset administratively down down
FastEthernet1/6 unassigned YES unset administratively down down
FastEthernet1/7 unassigned YES unset administratively down down
FastEthernet1/8 unassigned YES unset administratively down down
FastEthernet1/9 unassigned YES unset administratively down down
FastEthernet1/10 unassigned YES unset administratively down down
FastEthernet1/11 unassigned YES unset administratively down down
FastEthernet1/12 unassigned YES unset administratively down down
FastEthernet1/13 unassigned YES unset administratively down down
FastEthernet1/14 unassigned YES unset administratively down down
FastEthernet1/15 unassigned YES unset administratively down down
Vlan1 10.1.1.1 YES manual up up
----------------------------------------------------------------------------------------------------------------
Corp#
show run
Building configuration...
Current configuration : 2073 bytes
!
version 15.1
no service timestamps log datetime msec
no service timestamps debug datetime msec
no service password-encryption
!
hostname Corp
!
!
!
enable secret 5 $1$mERr$V5ujdIM9bTB/I.ipB0gkJ0
!
!
!
!
!
!
no ip cef
no ipv6 cef
!
!
!
!
license udi pid CISCO2811/K9 sn FTX1017U440-
!
!
!
!
!
!
!
!
!
no ip domain-lookup
!
!
spanning-tree mode pvst
!
!
!
!
!
!
interface FastEthernet0/0
description connection to R3
ip address 10.1.5.1 255.255.255.0
duplex auto
speed auto
!
interface FastEthernet0/1
no ip address
duplex auto
speed auto
shutdown
!
interface Serial0/0/0
description 1st connection to R1
ip address 10.1.2.1 255.255.255.0
clock rate 2000000
!
interface Serial0/0/1
description 2nd connection to R1
ip address 10.1.3.1 255.255.255.0
clock rate 2000000
!
interface Serial0/1/0
description connection to R2
ip address 10.1.4.1 255.255.255.0
!
interface Serial0/1/1
no ip address
clock rate 2000000
shutdown
!
interface FastEthernet1/0
description switch port connection to WWW Server
!
interface FastEthernet1/1
description switch port connection to Email Server
!
interface FastEthernet1/2
description switch port connection to DNS Server
!
interface FastEthernet1/3
shutdown
!
interface FastEthernet1/4
shutdown
!
interface FastEthernet1/5
shutdown
!
interface FastEthernet1/6
shutdown
!
interface FastEthernet1/7
shutdown
!
interface FastEthernet1/8
shutdown
!
interface FastEthernet1/9
shutdown
!
interface FastEthernet1/10
shutdown
!
interface FastEthernet1/11
shutdown
!
interface FastEthernet1/12
shutdown
!
interface FastEthernet1/13
shutdown
!
interface FastEthernet1/14
shutdown
!
interface FastEthernet1/15
shutdown
!
interface Vlan1
description Switch Card to Core Network
ip address 10.1.1.1 255.255.255.0
!
ip classless
!
ip flow-export version 9
!
!
!
banner motd ^C This is my Corp 2811 ISR Router ^C
!
!
!
!
!
line con 0
exec-timeout 0 0
password console
logging synchronous
login
!
line aux 0
password aux
login
!
line vty 0 4
password telnet
login
line vty 5 15
password telnet
login
!
!
!
end
-----------------------------------------------------------------------------------------------------------------------
more configurations:
R1
Router(config)#
hostname R1
R1(config)#
enable secret todd
R1(config)#
int s0/0/0
R1(config-if)#
ip address 10.1.2.2 255.255.255.0
R1(config-if)#
Decription 1st connection to corp router
R1(config-if)#
no shut
-----------------------------------------------------------------------------------------------
R1(config-if)#
int s0/0/1
R1(config-if)#
ip address 10.1.3.2 255.255.255.0
R1(config-if)#
Decription 2nd connection to corp router
R1(config-if)#
no shut
-----------------------------------------------------------------------------------------------
R1(config-if)#
int f0/0
R1(config-if)#
ip address 192.168.10.1 255.255.255.0
R1(config-if)#
Decription connection to finance
R1(config-if)#
no shut
-----------------------------------------------------------------------------------------------
R1(config-if)#
int f0/1
R1(config-if)#
ip address 192.168.20.1 255.255.255.0
R1(config-if)#
Decription connection to marketing
R1(config-if)#
no shut
R1(config-if)#
exit
-----------------------------------------------------------------------------------------------
R1(config)#
line con 0
R1(config-line)#
password console
R1(config-line)#
login
R1(config-line)#
logging synchronous
R1(config-line)#
exec-timeout 0 0
-----------------------------------------------------------------------------------------------
R1(config-line)#
line aux 0
R1(config-line)#
password aux
R1(config-line)#
login
R1(config-line)#
exit
-----------------------------------------------------------------------------------------------
R1(config)#
line vty 0 ?
<0-15> Last Line number
R1(config)#
line vty 0 807
R1(config-line)#
password telnet
R1(config-line)#
login
R1(config-line)#
banner motd # This is my R1 Router #
R1(config-line)#
exit
-----------------------------------------------------------------------------------------------
R1(config)#
no ip domain-lookup
R1(config)#
exit
R1#
copy run start
R2
Router(config)#
hostname R2
R2(config)#
enable secret todd
R2(config)#
int s0/0/0
R2(config-if)#
ip address 10.1.4.2 255.255.255.0
R2(config-if)#
description connection to corp router
R2(config-if)#
no shut
-----------------------------------------------------------------------------------------------
R2(config-if)#
int f0/0
R2(config-if)#
ip address 192.168.30.1 255.255.255.0
R2(config-if)#
description connection to sales PC
R2(config-if)#
no shut
-----------------------------------------------------------------------------------------------
R2(config-if)#
int f0/1
R2(config-if)#
ip address 192.168.40.1 255.255.255.0
R2(config-if)#
description connection to HR pc
R2(config-if)#
no shut
-----------------------------------------------------------------------------------------------
R2(config-if)#
line con 0
R2(config-line)#
password console
R2(config-line)#
login
R2(config-line)#
logging synchronous
R2(config-line)#
exec-timeout 0 0
-----------------------------------------------------------------------------------------------
R2(config-line)#
line aux 0
R2(config-line)#
password aux
R2(config-line)#
login
R2(config-line)#
exit
-----------------------------------------------------------------------------------------------
R2(config)#
line vty 0 ?
<0-15> Last Line number
R2(config)#
line vty 0 807
R2(config-line)#
password telnet
R2(config-line)#
login
R2(config-line)#
banner motd # This is my R1 Router #
R2(config-line)#
exit
-----------------------------------------------------------------------------------------------
R2(config)#
no ip domain-lookup
R2(config)#
exit
R2#
copy run start
R3
Router(config)#
hostname R3
R3(config)#
enable secret todd
R3(config)#
int f0/0
R3(config-if)#
ip address 10.1.5.2 255.255.255.0
R3(config-if)#
description connection to corp router
R3(config-if)#
no shut
-----------------------------------------------------------------------------------------------
R3(config-if)#
int dot11radio0/0/0
R3(config-if)#
ip address 172.16.10.1 255.255.255.0
R3(config-if)#
description WLAN for mobile user
R3(config-if)#
no shut
R3(config-if)#
ssid ADMIN
stuck here 2-5-22-- packet tracer isnt taking me into the config-if-ssid prompt
R3(config-if-ssid)#
guest-mode
R3(config-if-ssid)#
authentication open
R3(config-if-ssid)#
ingrastructure-ssid
R3(config-if-ssid)#
exit
-----------------------------------------------------------------------------------------------
R3(config-if)#
line con 0
R3(config-line)#
password console
R3(config-line)#
login
R3(config-line)#
logging synchronous
R3(config-line)#
exec-timeout 0 0
-----------------------------------------------------------------------------------------------
R3(config-line)#
line aux 0
R3(config-line)#
password aux
R3(config-line)#
login
R3(config-line)#
exit
-----------------------------------------------------------------------------------------------
R3(config)#
line vty 0 ?
<0-15> Last Line number
R3(config)#
line vty 0 807
R3(config-line)#
password telnet
R3(config-line)#
login
R3(config-line)#
banner motd # This is my R1 Router #
R3(config-line)#
exit
-----------------------------------------------------------------------------------------------
R3(config)#
no ip domain-lookup
R3(config)#
exit
R3#
copy run start
PROBLEM
i cant get into conf-if-ssid prompt
R3(config-if)#
ssid ADMIN
%LINK-5-CHANGED: Interface Dot11Radio0/0/0, changed state to administratively down
%LINEPROTO-5-UPDOWN: Line protocol on Interface Dot11Radio0/0/0, changed state to down
%LINK-5-CHANGED: Interface Dot11Radio0/0/0, changed state to up
%LINEPROTO-5-UPDOWN: Line protocol on Interface Dot11Radio0/0/0, changed state to up
R3(config-if)#
research led me to this thread, which is a dead end:
further research led me here:
R3(config)# global config mode
R3(config)#
dot11 ssid ADMIN
creates an SSID or lets you config an existing SSID
R3(config-ssid)#
guest-mode
R3(config-ssid)#
%LINK-5-CHANGED: Interface Dot11Radio0/0/0, changed state to administratively down
%LINEPROTO-5-UPDOWN: Line protocol on Interface Dot11Radio0/0/0, changed state to down
%LINK-5-CHANGED: Interface Dot11Radio0/0/0, changed state to up
%LINEPROTO-5-UPDOWN: Line protocol on Interface Dot11Radio0/0/0, changed state to up
R3(config-ssid)#
authentication open
R3(config-ssid)#
%LINK-5-CHANGED: Interface Dot11Radio0/0/0, changed state to administratively down
%LINEPROTO-5-UPDOWN: Line protocol on Interface Dot11Radio0/0/0, changed state to down
%LINK-5-CHANGED: Interface Dot11Radio0/0/0, changed state to up
%LINEPROTO-5-UPDOWN: Line protocol on Interface Dot11Radio0/0/0, changed state to up
R3(config-ssid)#
infrastructure-ssid
R3(config-ssid)#infrastructure-ssid
^
% Invalid input detected at '^' marker.
this command given by the book doesnt appear to be valid
R3(config-ssid)#
?
authentication authentication method
exit Exit from ssid sub mode
guest-mode guest ssid
no Negate a command or set it's defaults
wpa-psk Configure Wi-Fi Protected Access pre-shared key
back into the interface to see what the options are
R3(config-ssid)#
int dot110/0/0
R3(config-if)#
?
arp Set arp type (arpa, probe, snap) or timeout or log options
bandwidth Set bandwidth informational parameter
cdp CDP interface subcommands
crypto Encryption/Decryption commands
delay Specify interface throughput delay
description Interface specific description
encryption Configure dot11 encryption parameters
exit Exit from interface configuration mode
fair-queue Enable Fair Queuing on an Interface
hold-queue Set hold queue depth
ip Interface Internet Protocol config commands
mac-address Manually set interface MAC address
mtu Set the interface Maximum Transmission Unit (MTU)
no Negate a command or set its defaults
priority-group Assign a priority group to an interface
service-policy Configure QoS Service Policy
shutdown Shutdown the selected interface
speed Set allowed radio bit rates
ssid Configure radio service set parameters
tx-ring-limit Configure PA level transmit ring limit
i'll consider the problem *mostly* solved. I was able to assign the SSD.
The infrastructure command may be expendable in this case... to be determined
here is our configuration for R3
R3#
show run
Building configuration...
Current configuration : 1682 bytes
!
version 15.1
no service timestamps log datetime msec
no service timestamps debug datetime msec
no service password-encryption
!
hostname R3
!
!
!
enable secret 5 $1$mERr$V5ujdIM9bTB/I.ipB0gkJ0
!
!
ip dhcp excluded-address 172.16.10.1 172.16.10.10
!
ip dhcp pool Admin
network 172.16.10.0 255.255.255.0
default-router 172.16.10.1
!
dot11 ssid ADMIN
authentication open
guest-mode
!
dot11 ssid ADMIN2
authentication open
guest-mode
!
!
!
ip cef
no ipv6 cef
!
!
!
!
license udi pid CISCO2811/K9 sn FTX1017RE40-
!
!
!
!
!
!
!
!
!
no ip domain-lookup
ip name-server 172.16.10.4
!
!
spanning-tree mode pvst
!
!
!
!
!
!
interface FastEthernet0/0
description connection to corp router
ip address 10.1.5.2 255.255.255.0
duplex auto
speed auto
!
interface FastEthernet0/1
no ip address
duplex auto
speed auto
shutdown
!
interface Dot11Radio0/0/0
description WAN for mobile
ip address 172.16.10.1 255.255.255.0
speed 12.0 18.0 24.0 36.0 48.0 54.0 6.0 9.0 basic-1.0 basic-11.0 basic-2.0 basic-5.5
ssid ADMIN2
!
interface Dot11Radio0/0/1
no ip address
speed 18.0 36.0 48.0 54.0 9.0 basic-12.0 basic-24.0 basic-6.0
!
interface Serial0/1/0
no ip address
clock rate 2000000
!
interface Serial0/1/1
no ip address
clock rate 2000000
!
interface Vlan1
no ip address
shutdown
!
router rip
version 2
network 10.0.0.0
network 172.16.0.0
!
ip classless
ip route 0.0.0.0 0.0.0.0 10.1.5.1
!
ip flow-export version 9
!
!
!
banner motd ^C this is R3 $
this is R3 ^C
!
!
!
!
!
line con 0
exec-timeout 0 0
password console
logging synchronous
login
!
line aux 0
password aux
login
!
line vty 0 4
password telnet
login
line vty 5 15
password telnet
login
!
!
!
end
to summarize...
the book is a little off here.
-----------------------------------------------------------------------------------------------
R3(config-if)#
int dot11radio0/0/0
R3(config-if)#
ip address 172.16.10.1 255.255.255.0
R3(config-if)#
description WLAN for mobile user
R3(config-if)#
no shut
at this point we have created a wireless interface with an IP address but no SSID exists on this router
interface Dot11Radio0/0/0
description test router 2
ip address 172.16.10.1 255.255.255.0
speed 12.0 18.0 24.0 36.0 48.0 54.0 6.0 9.0 basic-1.0 basic-11.0 basic-2.0 basic-5.5
Trying to use the command "ssid ADMIN" doesnt work here. The below commands are invalid here:
R3(config-if)#
ssid ADMIN
R3(config-if-ssid)#
guest-mode
R3(config-if-ssid)#
authentication open
R3(config-if-ssid)#
ingrastructure-ssid
R3(config-if-ssid)#
exit
-----------------------------------------------------------------------------------------------
We need to drop out of config-if, back to config, and enter SSID config mode
-----------------------------------------------------------------------------------------------
R3(config-if)#
exit
R3(config)#
dot11 ssid ADMIN2 creates an ssid named ADMIN2, and puts us into SSID config mode
R3(config-ssid)#
guest-mode
R3(config-ssid)#
authentication open
then out of config-ssid and back to interface config
R3(config-ssid)#
exit
R3(config)
int dot11r0/0/0
R3(config-if)
?
arp Set arp type (arpa, probe, snap) or timeout or log options
bandwidth Set bandwidth informational parameter
cdp CDP interface subcommands
crypto Encryption/Decryption commands
delay Specify interface throughput delay
description Interface specific description
encryption Configure dot11 encryption parameters
exit Exit from interface configuration mode
fair-queue Enable Fair Queuing on an Interface
hold-queue Set hold queue depth
ip Interface Internet Protocol config commands
mac-address Manually set interface MAC address
mtu Set the interface Maximum Transmission Unit (MTU)
no Negate a command or set its defaults
priority-group Assign a priority group to an interface
service-policy Configure QoS Service Policy
shutdown Shutdown the selected interface
speed Set allowed radio bit rates
ssid Configure radio service set parameters
tx-ring-limit Configure PA level transmit ring limit
we have the option for ssid
R3(config-if)
ssid ADMIN2
%LINK-5-CHANGED: Interface Dot11Radio0/0/0, changed state to administratively down
%LINEPROTO-5-UPDOWN: Line protocol on Interface Dot11Radio0/0/0, changed state to down
%LINK-5-CHANGED: Interface Dot11Radio0/0/0, changed state to up
%LINEPROTO-5-UPDOWN: Line protocol on Interface Dot11Radio0/0/0, changed state to up
the router resets the interface..
-----------------------------------------------------------------------------------------------
R3(config-if)
do show run
[cut]
!
!
dot11 ssid ADMIN2
authentication open
guest-mode
!
!
[cut]
!
interface Dot11Radio0/0/0
description test router 2
ip address 172.16.10.1 255.255.255.0
speed 12.0 18.0 24.0 36.0 48.0 54.0 6.0 9.0 basic-1.0 basic-11.0 basic-2.0 basic-5.5
ssid ADMIN2
!
[cut]
the SSID is created and assigned to the interface
To summarize.
Wrong: create the dot11 interface, then create the SSID from CONFIG-IF mode, which puts you into CONFIG-IF-SSID (there is no such mode on this router) mode, then modify the ssid from there...
Correct: create the dot11 interface. Exit CONFIG-IF and go back to GLOBAL CONFIG. Create the SSID which puts you in CONFIG-SSID mode.
Configure the ssid. Then exit CONFIG-SSID. Back into CONFIG-IF, assign the SSID
We have one more task for R3- Configuring the DHCP pool for wireless clients.
R3(config)#
ip dhcp pool Admin creating the pool name as "Admin"
R3(dhcp-config)#
network 172.16.10.0 255.255.255.0
R3(dhcp-config)#
default-router 172.16.10.1 aka default-gateway for clients in the pool
R3(dhcp-config)#
ip name-server 172.16.10.4 dns server
*automatically exits dhcp-config prompt*
R3(config)#
ip dhcp excluded-address 172.16.10.1 172.16.10.10 excludes the range given
172.16.10.1 is the router interface- we need to specifically exclude it from the pool
this setup should allow the wireless client to pick up an IP after connecting to the open SSID.
However, I was having trouble at first-
even though I seemed to have the SSID set correctly, i was hitting a WEP password prompt
i didnt see any obvious issues with the wifi module im using on the laptop:
The Linksys-WPC300N module provides one 2.4GHz wireless interface suitable for connection to wireless networks.
The module supports protocols that use Ethernet for LAN access.
I ended up creating a new SSID, with the same settings as the original:
R3(config)#
dot11 ssid ADMIN2
R3(config-ssid)#
guest-mode
R3(config-ssid)#
authentication open
and then I assigned the ip address to ssid ADMIN2 instead of the orginal ADMIN ssid
R3(config)#
int dot110/0/0
R3(config-if)#
ip address 172.16.10.1 255.255.255.0
R3(config-if)#
description WLAN for mobile user
R3(config-if)#
no shut
R3(config-if)#
ssid ADMIN2
R3#
show run
Building configuration...
Current configuration : 1467 bytes
!
version 15.1
no service timestamps log datetime msec
no service timestamps debug datetime msec
no service password-encryption
!
hostname R3
!
!
!
enable secret 5 $1$mERr$V5ujdIM9bTB/I.ipB0gkJ0
!
!
ip dhcp excluded-address 172.16.10.1 172.16.10.10
!
ip dhcp pool Admin
network 172.16.10.0 255.255.255.0
default-router 172.16.10.1
!
dot11 ssid ADMIN
authentication open
guest-mode
!
dot11 ssid ADMIN2
authentication open
guest-mode
!
!
!
ip cef
no ipv6 cef
!
!
!
!
license udi pid CISCO2811/K9 sn FTX1017RE40-
!
!
!
!
!
!
!
!
!
no ip domain-lookup
ip name-server 172.16.10.4
!
!
spanning-tree mode pvst
!
!
!
!
!
!
interface FastEthernet0/0
description connection to corp router
ip address 10.1.5.2 255.255.255.0
duplex auto
speed auto
!
interface FastEthernet0/1
no ip address
duplex auto
speed auto
shutdown
!
interface Dot11Radio0/0/0
description WAN for mobile
ip address 172.16.10.1 255.255.255.0
speed 12.0 18.0 24.0 36.0 48.0 54.0 6.0 9.0 basic-1.0 basic-11.0 basic-2.0 basic-5.5
ssid ADMIN2
!
interface Dot11Radio0/0/1
no ip address
speed 18.0 36.0 48.0 54.0 9.0 basic-12.0 basic-24.0 basic-6.0
!
interface Vlan1
no ip address
shutdown
!
ip classless
!
ip flow-export version 9
!
!
!
banner motd ^C this is R3 $
this is R3 ^C
!
!
!
!
!
line con 0
exec-timeout 0 0
password console
logging synchronous
login
!
line aux 0
password aux
login
!
line vty 0 4
password telnet
login
line vty 5 15
password telnet
login
!
!
!
end
Recall the DHCP configuration on R3:
R3(config)#
ip dhcp pool Admin creating the pool name as "Admin"
R3(dhcp-config)#
network 172.16.10.0 255.255.255.0
R3(dhcp-config)#
default-router 172.16.10.1 aka default-gateway for clients in the pool
R3(dhcp-config)#
ip name-server 172.16.10.4 dns server
*automatically exits dhcp-config prompt*
R3(config)#
ip dhcp excluded-address 172.16.10.1 172.16.10.10 excludes the range given
172.16.10.1 is the router interface- we need to specifically exclude it from the pool
we can check the configuration:
R3#
show ip dhcp pool
Pool Admin :
Utilization mark (high/low) : 100 / 0
Subnet size (first/next) : 0 / 0
Total addresses : 254
Leased addresses : 1
Excluded addresses : 1
Pending event : none
1 subnet is currently in the pool
Current index IP address range Leased/Excluded/Total
172.16.10.1 172.16.10.1 - 172.16.10.254 1 / 1 / 254
R3#
show ip dhcp binding
IP address Client-ID/ Lease expiration Type
Hardware address
172.16.10.11 00D0.979A.733B -- Automatic
the show command is becoming more familiar
R3#
show ip?
access-lists List access lists
arp IP ARP table
bgp BGP information
cache IP fast-switching route cache
cef Cisco Express Forwarding
dhcp Show items in the DHCP database
eigrp IP-EIGRP show commands
inspect CBAC (Context Based Access Control) information
interface IP interface status and configuration
ips IPS (Intrusion Prevention System) information
nat IP NAT information
nbar Network-Based Application Recognition
ospf OSPF information
protocols IP routing protocol process parameters and statistics
rip IP RIP show commands
route IP routing table
ssh Information on SSH
we'll use show ip route soon on all the routers. For now, here is the output for R3:
R3#
show ip route
Codes: L - local, C - connected, S - static, R - RIP, M - mobile, B - BGP
D - EIGRP, EX - EIGRP external, O - OSPF, IA - OSPF inter area
N1 - OSPF NSSA external type 1, N2 - OSPF NSSA external type 2
E1 - OSPF external type 1, E2 - OSPF external type 2, E - EGP
i - IS-IS, L1 - IS-IS level-1, L2 - IS-IS level-2, ia - IS-IS inter area
* - candidate default, U - per-user static route, o - ODR
P - periodic downloaded static route
Gateway of last resort is not set
10.0.0.0/8 is variably subnetted, 2 subnets, 2 masks
C 10.1.5.0/24 is directly connected, FastEthernet0/0
L 10.1.5.2/32 is directly connected, FastEthernet0/0
172.16.0.0/16 is variably subnetted, 2 subnets, 2 masks
C 172.16.10.0/24 is directly connected, Dot11Radio0/0/0
L 172.16.10.1/32 is directly connected, Dot11Radio0/0/0
Before moving on to the routing configurations, here is a review of the topology
I have switched over to the DrawIO diagram app to lay out the topology.
The Packet Tracer diagram becomes
too crowded to see the labels; it's labeling system forces awkward positioning of the objects; the interface
label's cant be moved, so if objects are too close together their labels cover eachother.. not good.
DrawIO allows a cleaner layout with plenty of room to label interfaces and ip addresses.
As a compromise, I'll use both.
I have the packet tracer objects spread out just enough to see the interfaces
and the label for each router. From here I can jump into the CLI for each device.
The DrawIO diagram allows me to cleary see IP addresses
I want to also review all of the configurations we just performed:
PROBLEM
The book specifies that of the two serial conections between R1 and Corp, there should be a DCE on each end..
Both of my DCE's are on the same end.
First lets be sure we understand what DCE means:
networkengineering.stackexchange.com/
One side of the link (DCE), has to transmit the clock signal, which controls the data rate, and the other side (DTE) receives the clock signal.
That is good enough for now. Note that while the book does specify in the diagram that each side should have a DCE, it was not actually mentioned in the configs.
We did not set a DCE or clock rate when conifguring those interfaces.
To fix this in my Packet Tracer topology, I did some quick research:
While this post wasnt pertaining to Packet Tracer, it got me thinking about the cable itself.
I deleted both of my existing serial connections and looked at the options for creating a new cable.
I noticed one is a DCE and one is a DTE:
Fixed the issue
back to the configuration overview: 4 routers, abbreviated show run output
Corp
interface FastEthernet0/0
description connection to R3
ip address 10.1.5.1 255.255.255.0
duplex auto
speed auto
!
interface FastEthernet0/1
no ip address
duplex auto
speed auto
shutdown
!
interface Serial0/0/0
description 1st connection to R1
ip address 10.1.2.1 255.255.255.0
!
interface Serial0/0/1
description 2nd connection to R1
ip address 10.1.3.1 255.255.255.0
clock rate 2000000
!
interface Serial0/1/0
description connection to R2
ip address 10.1.4.1 255.255.255.0
!
interface Vlan1
description Switch Card to Core Network
ip address 10.1.1.1 255.255.255.0
!
interface FastEthernet1/0
description switch port connection to WWW Server
switchport mode access
switchport nonegotiate
!
interface FastEthernet1/1
description switch port connection to Email Server
switchport mode access
switchport nonegotiate
!
interface FastEthernet1/2
description switch port connection to DNS Server
switchport mode access
switchport nonegotiate
!
R1
interface FastEthernet0/0
description connection to Finance
ip address 192.168.10.1 255.255.255.0
duplex auto
speed auto
!
interface FastEthernet0/1
description connection to Marketing
ip address 192.168.20.1 255.255.255.0
duplex auto
speed auto
!
interface Serial0/0/0
description 1st connection to Corp router
ip address 10.1.2.2 255.255.255.0
clock rate 2000000
!
interface Serial0/0/1
description 2nd connecction to Corp router
ip address 10.1.3.2 255.255.255.0
!
R2
interface FastEthernet0/0
description Connection to Sales PC
ip address 192.168.30.1 255.255.255.0
duplex auto
speed auto
!
interface FastEthernet0/1
description Connection to HR PC
ip address 192.168.40.1 255.255.255.0
duplex auto
speed auto
!
interface Serial0/0/0
description Connection to Corp Router
ip address 10.1.4.2 255.255.255.0
clock rate 2000000
!
interface Serial0/0/1
no ip address
clock rate 2000000
shutdown
!
R3
interface FastEthernet0/0
description connection to corp router
ip address 10.1.5.2 255.255.255.0
duplex auto
speed auto
!
interface FastEthernet0/1
no ip address
duplex auto
speed auto
shutdown
!
interface Dot11Radio0/0/0
description WAN for mobile
ip address 172.16.10.1 255.255.255.0
speed 12.0 18.0 24.0 36.0 48.0 54.0 6.0 9.0 basic-1.0 basic-11.0 basic-2.0 basic-5.5
ssid ADMIN2
and here is the output of show ip route for each router
Codes: C - connected, S - static, I - IGRP, R - RIP, M - mobile, B - BGP
D - EIGRP, EX - EIGRP external, O - OSPF, IA - OSPF inter area
N1 - OSPF NSSA external type 1, N2 - OSPF NSSA external type 2
E1 - OSPF external type 1, E2 - OSPF external type 2, E - EGP
i - IS-IS, L1 - IS-IS level-1, L2 - IS-IS level-2, ia - IS-IS inter area
* - candidate default, U - per-user static route, o - ODR
P - periodic downloaded static route
Gateway of last resort is not set
Corp
10.0.0.0/24 is subnetted, 2 subnets
C 10.1.2.0 is directly connected, Serial0/0/0
C 10.1.3.0 is directly connected, Serial0/0/1
C 192.168.10.0/24 is directly connected, FastEthernet0/0
C 192.168.20.0/24 is directly connected, FastEthernet0/1
R1
10.0.0.0/24 is subnetted, 2 subnets
C 10.1.2.0 is directly connected, Serial0/0/0
C 10.1.3.0 is directly connected, Serial0/0/1
C 192.168.10.0/24 is directly connected, FastEthernet0/0
C 192.168.20.0/24 is directly connected, FastEthernet0/1
R2
10.0.0.0/24 is subnetted, 1 subnets
C 10.1.4.0 is directly connected, Serial0/0/0
C 192.168.30.0/24 is directly connected, FastEthernet0/0
C 192.168.40.0/24 is directly connected, FastEthernet0/1
R3
10.0.0.0/8 is variably subnetted, 2 subnets, 2 masks
C 10.1.5.0/24 is directly connected, FastEthernet0/0
L 10.1.5.2/32 is directly connected, FastEthernet0/0
172.16.0.0/16 is variably subnetted, 2 subnets, 2 masks
C 172.16.10.0/24 is directly connected, Dot11Radio0/0/0
L 172.16.10.1/32 is directly connected, Dot11Radio0/0/0
Note that this is before we have configured any 'routing'. We are seeing configured, directly connected networks.
The output for R3 is particularly interesting
What does 'variably' subnetted mean, and what is the "L" next to these routes. And why do they have a mask of 32?
R3
10.0.0.0/8 is variably subnetted, 2 subnets, 2 masks
C 10.1.5.0/24 is directly connected, FastEthernet0/0
L 10.1.5.2/32 is directly connected, FastEthernet0/0
172.16.0.0/16 is variably subnetted, 2 subnets, 2 masks
C 172.16.10.0/24 is directly connected, Dot11Radio0/0/0
L 172.16.10.1/32 is directly connected, Dot11Radio0/0/0
Cisco forums
That makes sense, but my question is why did the other routing tables not behave the same way? R3 is the only one that shows "L" routes.
The book tells us we're using two different model routers, and indeed they are running different IOS versions:
NOTE that at the time the book was published IOS 15 was not released yet, so the book assumes all routers are running 12.4
But that still doesnt explain why Corp and R3 are behaving differently..
Corp
10.0.0.0/24 is subnetted, 2 subnets
C 10.1.2.0 is directly connected, Serial0/0/0
C 10.1.3.0 is directly connected, Serial0/0/1
C 192.168.10.0/24 is directly connected, FastEthernet0/0
C 192.168.20.0/24 is directly connected, FastEthernet0/1
R1
10.0.0.0/24 is subnetted, 2 subnets
C 10.1.2.0 is directly connected, Serial0/0/0
C 10.1.3.0 is directly connected, Serial0/0/1
C 192.168.10.0/24 is directly connected, FastEthernet0/0
C 192.168.20.0/24 is directly connected, FastEthernet0/1
R2
10.0.0.0/24 is subnetted, 1 subnets
C 10.1.4.0 is directly connected, Serial0/0/0
C 192.168.30.0/24 is directly connected, FastEthernet0/0
C 192.168.40.0/24 is directly connected, FastEthernet0/1
R3
10.0.0.0/8 is variably subnetted, 2 subnets, 2 masks
C 10.1.5.0/24 is directly connected, FastEthernet0/0
L 10.1.5.2/32 is directly connected, FastEthernet0/0
172.16.0.0/16 is variably subnetted, 2 subnets, 2 masks
C 172.16.10.0/24 is directly connected, Dot11Radio0/0/0
L 172.16.10.1/32 is directly connected, Dot11Radio0/0/0
how are Corp and R3 different?
The answer is, they are not...
I have accidentally displayed the R1 output to the Corp windows. Error in translating data from the IOS to this webpage..
here's the corrected output.
Corp
10.0.0.0/8 is variably subnetted, 10 subnets, 2 masks
C 10.1.1.0/24 is directly connected, Vlan1
L 10.1.1.1/32 is directly connected, Vlan1
C 10.1.2.0/24 is directly connected, Serial0/0/0
L 10.1.2.1/32 is directly connected, Serial0/0/0
C 10.1.3.0/24 is directly connected, Serial0/0/1
L 10.1.3.1/32 is directly connected, Serial0/0/1
C 10.1.4.0/24 is directly connected, Serial0/1/0
L 10.1.4.1/32 is directly connected, Serial0/1/0
C 10.1.5.0/24 is directly connected, FastEthernet0/0
L 10.1.5.1/32 is directly connected, FastEthernet0/0
R1
10.0.0.0/24 is subnetted, 2 subnets
C 10.1.2.0 is directly connected, Serial0/0/0
C 10.1.3.0 is directly connected, Serial0/0/1
C 192.168.10.0/24 is directly connected, FastEthernet0/0
C 192.168.20.0/24 is directly connected, FastEthernet0/1
R2
10.0.0.0/24 is subnetted, 1 subnets
C 10.1.4.0 is directly connected, Serial0/0/0
C 192.168.30.0/24 is directly connected, FastEthernet0/0
C 192.168.40.0/24 is directly connected, FastEthernet0/1
R3
10.0.0.0/8 is variably subnetted, 2 subnets, 2 masks
C 10.1.5.0/24 is directly connected, FastEthernet0/0
L 10.1.5.2/32 is directly connected, FastEthernet0/0
172.16.0.0/16 is variably subnetted, 2 subnets, 2 masks
C 172.16.10.0/24 is directly connected, Dot11Radio0/0/0
L 172.16.10.1/32 is directly connected, Dot11Radio0/0/0
We do indeed see consistent behavior differences between IOS versions 12.4 and 15.1
recap Corp and R3 outputs:
update topology with Router versions
That covers the first half of Chapter 8. Now we are ready to configure IP routing on our network.
There are three ways: Static, Default, Dynamic
To set up static routes, we simply need to program the routes using the ip route command
Syntax
ip route
[
destination network
]
[
mask
]
[
next hop
]
[
exitinterface
]
[
administrative distance
]
[
permanent
]
destination network and mask
the network data we're adding to the routing table
next-hop address
the address of the next-hop router that will receive the packet and forward to the remote network.
This is the IP address of a router interface that is directly connected.
It must be pingable.
exit interface
can be used instead of next hop address
administrative distance
by default, static routes have an admin distance of 1 if you use a next hop, or 0 if you use exit interface.
You can change the value by adding an administrative weight at the end of the command. More on this later with dynamic routing.
permanent
if the interface is shut down or the router cant communicate to the next hp router, the route will automatically be discarded from the table by default.
The 'permanent' option keeps the entry in the routing table indefenitely.
-----------------------------------------------------------------------------------------------------
Corp has automatically picked up 5 routes that are directly connected:
10.1.1.0 to corp switch card
10.1.2.0 to R1
10.1.3.0 to R1
10.1.4.0 to R2
10.1.5.0 to R3
We need to program 5 more routes:
192.168.10.0 traverse R1
192.168.20.0 traverse R1
192.168.30.0 traverse R1
192.168.40.0 traverse R2
172.16.10.0 traverse R3
-----------------------------------------------------------------------------------------------------
R1 has automatically picked up 4 routes that are directly connected:
10.1.2.0
10.1.3.0
192.168.10.0
192.168.20.0
We need to program 6 more routes:
10.1.1.0
10.1.4.0
10.1.5.0
192.168.30.0
192.168.40.0
172.16.10.0
-----------------------------------------------------------------------------------------------------
R2 has automatically picked up 3 routes that are directly connected:
10.1.4.0
192.168.30.0
192.168.40.0
We need to program 7 more routes:
10.1.1.0
10.1.2.0
10.1.3.0
10.1.5.0
192.168.10.0
192.168.20.0
172.16.10.0
-----------------------------------------------------------------------------------------------------
R3 has automatically picked up 2 routes that are directly connected:
10.1.5.0
172.16.10.0
We need to program 8 more routes:
10.1.1.0
10.1.2.0
10.1.3.0
10.1.4.0
192.168.10.0
192.168.20.0
192.168.30.0
192.168.40.0
Notice the pattern- each router ends up with 10 routes
There are 10 routes total in this topology. AKA ten broadcast domains
Programming the routes
Corp
Corp(config)#
ip route 192.168.10.0 255.255.255.0 10.1.2.2 150
Corp(config)#
ip route 192.168.20.0 255.255.255.0 10.1.3.2 150
Corp(config)#
ip route 192.168.30.0 255.255.255.0 10.1.4.2 150
Corp(config)#
ip route 192.168.40.0 255.255.255.0 10.1.4.2 150
Corp(config)#
ip route 172.16.10.0 255.255.255.0 10.1.5.2 150
Corp(config)#
do show ip route
In the first line, the router is saying that a
classful A network is being subnetted
There are 5 routes directly connected
We see two lines per route (one for the network and one
for the interface(/32)-
10.0.0.0/8 is variably subnetted, 10 subnets, 2 masks
C 10.1.1.0/24 is directly connected, Vlan1
L 10.1.1.1/32 is directly connected, Vlan1
C 10.1.2.0/24 is directly connected, Serial0/0/0
L 10.1.2.1/32 is directly connected, Serial0/0/0
C 10.1.3.0/24 is directly connected, Serial0/0/1
L 10.1.3.1/32 is directly connected, Serial0/0/1
C 10.1.4.0/24 is directly connected, Serial0/1/0
L 10.1.4.1/32 is directly connected, Serial0/1/0
C 10.1.5.0/24 is directly connected, FastEthernet0/0
L 10.1.5.1/32 is directly connected, FastEthernet0/0
and 5 routes that require traversal of a router to reach
172.16.0.0/24 is subnetted, 1 subnets
S 172.16.10.0/24 [150/0] via 10.1.5.2
S 192.168.10.0/24 [150/0] via 10.1.2.2
S 192.168.20.0/24 [150/0] via 10.1.3.2
S 192.168.30.0/24 [150/0] via 10.1.4.2
S 192.168.40.0/24 [150/0] via 10.1.4.2
R1
R1(config)#
ip route 10.1.1.0 255.255.255.0 10.1.2.1 150
R1(config)#
ip route 10.1.4.0 255.255.255.0 10.1.3.1 150
R1(config)#
ip route 10.1.5.0 255.255.255.0 10.1.2.1 150
R1(config)#
ip route 192.168.30.0 255.255.255.0 10.1.3.1 150
R1(config)#
ip route 192.168.40.0 255.255.255.0 10.1.2.1 150
R1(config)#
ip route 172.16.10.0 255.255.255.0 10.1.3.1 150
the only way to get across the corp router is to go into it via 10.1.2.1 or 10.1.3.1
R1(config)#
do show ip route
10.0.0.0/24 is subnetted, 5 subnets
S 10.1.1.0 [150/0] via 10.1.2.1
C 10.1.2.0 is directly connected, Serial0/0/0
C 10.1.3.0 is directly connected, Serial0/0/1
S 10.1.4.0 [150/0] via 10.1.3.1
S 10.1.5.0 [150/0] via 10.1.2.1
172.16.0.0/24 is subnetted, 1 subnets
S 172.16.10.0 [150/0] via 10.1.3.1
C 192.168.10.0/24 is directly connected, FastEthernet0/0
C 192.168.20.0/24 is directly connected, FastEthernet0/1
S 192.168.30.0/24 [150/0] via 10.1.3.1
S 192.168.40.0/24 [150/0] via 10.1.2.1
R2
R2(config)#
iproute 10.1.1.0 255.255.255.0 10.1.4.1 150
R2(config)#
iproute 10.1.2.0 255.255.255.0 10.1.4.1 150
R2(config)#
iproute 10.1.3.0 255.255.255.0 10.1.4.1 150
R2(config)#
iproute 10.1.5.0 255.255.255.0 10.1.4.1 150
R2(config)#
iproute 192.168.10.0 255.255.255.0 10.1.4.1 150
R2(config)#
iproute 192.168.20.0 255.255.255.0 10.1.4.1 150
the only way to get across Corp is to go into it via 10.1.4.1
R2(config)#
do show ip route
10.0.0.0/24 is subnetted, 5 subnets
S 10.1.1.0 [150/0] via 10.1.4.1
S 10.1.2.0 [150/0] via 10.1.4.1
S 10.1.3.0 [150/0] via 10.1.4.1
C 10.1.4.0 is directly connected, Serial0/0/0
S 10.1.5.0 [150/0] via 10.1.4.1
172.16.0.0/24 is subnetted, 1 subnets
S 172.16.10.0 [150/0] via 10.1.4.1
S 192.168.10.0/24 [150/0] via 10.1.4.1
S 192.168.20.0/24 [150/0] via 10.1.4.1
C 192.168.30.0/24 is directly connected, FastEthernet0/0
C 192.168.40.0/24 is directly connected, FastEthernet0/1
R3
R3(config)#
ip route 10.1.1.0 255.255.255.0 fastethernet 0/0 150
R3(config)#
ip route 10.1.2.0 255.255.255.0 fastethernet 0/0 150
R3(config)#
ip route 10.1.3.0 255.255.255.0 fastethernet 0/0 150
R3(config)#
ip route 10.1.4.0 255.255.255.0 fastethernet 0/0 150
R3(config)#
ip route 192.168.10.0 255.255.255.0 fastethernet 0/0 150
R3(config)#
ip route 192.168.20.0 255.255.255.0 fastethernet 0/0 150
R3(config)#
ip route 192.168.30.0 255.255.255.0 fastethernet 0/0 150
R3(config)#
ip route 192.168.40.0 255.255.255.0 fastethernet 0/0 150
the only way to get across Corp is to EXIT R3 via F0/0
R3(config)#
do show ip route
10.0.0.0/8 is variably subnetted, 6 subnets, 2 masks
S 10.1.1.0/24 is directly connected, FastEthernet0/0
S 10.1.2.0/24 is directly connected, FastEthernet0/0
S 10.1.3.0/24 is directly connected, FastEthernet0/0
S 10.1.4.0/24 is directly connected, FastEthernet0/0
C 10.1.5.0/24 is directly connected, FastEthernet0/0
L 10.1.5.2/32 is directly connected, FastEthernet0/0
172.16.0.0/16 is variably subnetted, 2 subnets, 2 masks
C 172.16.10.0/24 is directly connected, Dot11Radio0/0/0
L 172.16.10.1/32 is directly connected, Dot11Radio0/0/0
S 192.168.10.0/24 is directly connected, FastEthernet0/0
S 192.168.20.0/24 is directly connected, FastEthernet0/0
S 192.168.30.0/24 is directly connected, FastEthernet0/0
S 192.168.40.0/24 is directly connected, FastEthernet0/0
before verifying connectivity across the network, we need to make sure all of our hosts are set. The book is giving us the IP addresses for the servers:
Server Gateway 10.1.1.1
ServerWeb 10.1.1.2
ServerEmail 10.1.1.3
ServerDNS 10.1.1.4
Now we can do some testing across the network:
R3#
ping 10.1.2.2
traverse Corp to R1
R3#
ping 10.1.1.1
traverse Corp to a Corp interface we arent directly connected to
R3#
ping 10.1.1.2
traverse Corp to Web server
R3#
ping 10.1.1.3
traverse Corp to Email server
R3#
ping 10.1.1.4
traverse Corp to DNS server
MobileUser
ping 192.168.10.2
traverse R3, Corp, R1 to Finance client
MobileUser
tracert 192.168.10.2
traverse R3, Corp, R1 to Finance client
Tracing route to 192.168.10.2 over a maximum of 30 hops:
1 19 ms 5 ms 20 ms 172.16.10.1
2 20 ms 6 ms 11 ms 10.1.5.1
3 11 ms 15 ms 10 ms 10.1.3.2
4 9 ms 13 ms 22 ms 192.168.10.2
Trace complete.
notice how the trace doesnt count an egress as a hop, only an ingress
ALSO NOTE that tracert is a Windows command.
the IOS equivalent is traceroute
notice how the output differs from the Windows command
R3
traceroute 192.168.10.2
Type escape sequence to abort.
Tracing the route to 192.168.10.2
1 10.1.5.1 0 msec 0 msec 0 msec
2 10.1.2.2 6 msec 0 msec 5 msec
3 192.168.10.2 1 msec 4 msec 3 msec
Default Routing
we could have done this on R3
R3(config)#
ip route 0.0.0.0 0.0.0.0 10.1.5.1
as an alternative to this configuration on R3
R3(config)#
ip route 10.1.1.0 255.255.255.0 fastethernet 0/0 150
R3(config)#
ip route 10.1.2.0 255.255.255.0 fastethernet 0/0 150
R3(config)#
ip route 10.1.3.0 255.255.255.0 fastethernet 0/0 150
R3(config)#
ip route 10.1.4.0 255.255.255.0 fastethernet 0/0 150
R3(config)#
ip route 192.168.10.0 255.255.255.0 fastethernet 0/0 150
R3(config)#
ip route 192.168.20.0 255.255.255.0 fastethernet 0/0 150
R3(config)#
ip route 192.168.30.0 255.255.255.0 fastethernet 0/0 150
R3(config)#
ip route 192.168.40.0 255.255.255.0 fastethernet 0/0 150
the only way to get across Corp is to EXIT R3 via F0/0
This is called default routing. It should only be used on 'stub routers'- those with only one exit path out of the network.
if you try to put a default route on a non-stub router, you could create loops, since there will be more than one path to other routers...
Think of a default route as a static route that uses a wildcard address and mask. The wildcard is 0.0.0.0
to further analyze this comparison, I'm going to remove the routes from R3...
R3(config)#
no ip route 10.1.1.0 255.255.255.0 fastethernet0/0 150
R3(config)#
no ip route 10.1.2.0 255.255.255.0 fastethernet0/0 150
R3(config)#
no ip route 10.1.3.0 255.255.255.0 fastethernet0/0 150
R3(config)#
no ip route 10.1.4.0 255.255.255.0 fastethernet0/0 150
R3(config)#
no ip route 192.168.10.0 255.255.255.0 fastethernet0/0 150
R3(config)#
no ip route 192.168.20.0 255.255.255.0 fastethernet0/0 150
R3(config)#
no ip route 192.168.30.0 255.255.255.0 fastethernet0/0 150
R3(config)#
no ip route 192.168.40.0 255.255.255.0 fastethernet0/0 150
and then set the default route instead.
R3#
ip route 0.0.0.0 0.0.0.0 10.1.5.1 --- ingress at next hop
OR
R3#
ip route 0.0.0.0 0.0.0.0 Fa0/0 --- egress interface
Then compare the output of show ip route
static routes set
R3#
show ip route
Gateway of last resort is not set
10.0.0.0/8 is variably subnetted, 6 subnets, 2 masks
S 10.1.1.0/24 is directly connected, FastEthernet0/0
S 10.1.2.0/24 is directly connected, FastEthernet0/0
S 10.1.3.0/24 is directly connected, FastEthernet0/0
S 10.1.4.0/24 is directly connected, FastEthernet0/0
C 10.1.5.0/24 is directly connected, FastEthernet0/0
L 10.1.5.2/32 is directly connected, FastEthernet0/0
172.16.0.0/16 is variably subnetted, 2 subnets, 2 masks
C 172.16.10.0/24 is directly connected, Dot11Radio0/0/0
L 172.16.10.1/32 is directly connected, Dot11Radio0/0/0
S 192.168.10.0/24 is directly connected, FastEthernet0/0
S 192.168.20.0/24 is directly connected, FastEthernet0/0
S 192.168.30.0/24 is directly connected, FastEthernet0/0
S 192.168.40.0/24 is directly connected, FastEthernet0/0
default route set
R3#
show ip route
Gateway of last resort is 10.1.5.1 to network 0.0.0.0
10.0.0.0/8 is variably subnetted, 2 subnets, 2 masks
C 10.1.5.0/24 is directly connected, FastEthernet0/0
L 10.1.5.2/32 is directly connected, FastEthernet0/0
172.16.0.0/16 is variably subnetted, 2 subnets, 2 masks
C 172.16.10.0/24 is directly connected, Dot11Radio0/0/0
L 172.16.10.1/32 is directly connected, Dot11Radio0/0/0
S* 0.0.0.0/0 [1/0] via 10.1.5.1
two directly connected networks- 10.1.5.0 and 172.16.10.0
anything not included in those networks goes to ingress of attached neighbor Corp 10.1.5.1
in this toplogy, that includes:
192.168.10.0
192.168.20.0
192.168.30.0
192.168.40.0
and
10.1.1.0
10.1.2.0
10.1.3.0
10.1.4.0
RIP Routing Information Protocol
R1(config)#
router ?
bgp Border Gateway Protocol (BGP)
eigrp Enhanced Interior Gateway Routing Protocol (EIGRP)
ospf Open Shortest Path First (OSPF)
rip Routing Information Protocol (RIP)
set RIP on Corp
Corp(config)#
router rip
Corp(config-router)#
network 10.0.0.0
set RIP on R1
R1(config)#
router rip
R1(config-router)#
network 10.0.0.0
R1 routing table
R1(config)#
do show ip route
10.0.0.0/24 is subnetted, 5 subnets
R 10.1.1.0 [120/1] via 10.1.2.1, 00:00:21, Serial0/0/0
[120/1] via 10.1.3.1, 00:00:21, Serial0/0/1
C 10.1.2.0 is directly connected, Serial0/0/0
C 10.1.3.0 is directly connected, Serial0/0/1
R 10.1.4.0 [120/1] via 10.1.2.1, 00:00:21, Serial0/0/0
[120/1] via 10.1.3.1, 00:00:21, Serial0/0/1
R 10.1.5.0 [120/1] via 10.1.2.1, 00:00:21, Serial0/0/0
[120/1] via 10.1.3.1, 00:00:21, Serial0/0/1
172.16.0.0/24 is subnetted, 1 subnets
S 172.16.10.0 [150/0] via 10.1.3.1
C 192.168.10.0/24 is directly connected, FastEthernet0/0
C 192.168.20.0/24 is directly connected, FastEthernet0/1
S 192.168.30.0/24 [150/0] via 10.1.3.1
S 192.168.40.0/24 [150/0] via 10.1.2.1
here's R1 before RIP, with only static routes set:
R1(config)#
do show ip route
10.0.0.0/24 is subnetted, 5 subnets
S 10.1.1.0 [150/0] via 10.1.2.1
C 10.1.2.0 is directly connected, Serial0/0/0
C 10.1.3.0 is directly connected, Serial0/0/1
S 10.1.4.0 [150/0] via 10.1.3.1
S 10.1.5.0 [150/0] via 10.1.2.1
172.16.0.0/24 is subnetted, 1 subnets
S 172.16.10.0 [150/0] via 10.1.3.1
C 192.168.10.0/24 is directly connected, FastEthernet0/0
C 192.168.20.0/24 is directly connected, FastEthernet0/1
S 192.168.30.0/24 [150/0] via 10.1.3.1
S 192.168.40.0/24 [150/0] via 10.1.2.1
These RIP routes are being advertised as available *to other RIP routers*.
CORP is advertisting THREE routes via RIP to R1 right now
10.1.1.0
10.1.4.0
10.1.5.0
access to those networks can be achieved by R1 by going THROUGH CORP via ingress .2.1 or .3.1
The advantage..... is that we didnt statically program these routes
we engaged RIP, on BOTH routers- R1 and Corp, and handed them BOTH the network "10.0.0.0"
So, why did RIP choose to display these particular routes
Keep in mind that the output above is from R1 only... In the context of the R1 ROUTER ONLY,
there are three relevant routes within the "10.0.0.0" parameter we specified. The three routes involve Corp.
Corp is sending RIP data about these routes to Corp.
Lets look closer at how this is happening:
here's our starting point before any RIP is set
here's our routing tables after i set RIP with 10.0.0.0 on both..
FIRST i set it on Corp, then R1.(per the book's instructions) As a result we are seeing RIP routes in R1 only....
then I went back to a fresh packet tracer file with no RIP set. And I set RIP in the opposite order;
FIRST i set it on R1, then Corp. And again, we are seeing RIP routes in R1 only....
I wanted to prove that it didnt matter which order we enabled RIP on the two routers. What matters here is that
we enable RIP on both of them with the criteria of 10.0.0.0
Recall the topology:
if Corp and R1 are set for RIP and given the criteria 10.0.0.0, meaning that we are trying to reach networks
within that range, then it follows that Corp will advertise 1.1.0, 1.4.0, and 1.5.0 to R1, because Corp stands between those networks
and R1
"Hi R1, I'm Corp I have three networks that fall inside 10.0.0.0, and you can reach them through me via .2.1 or .3.1"
It also follows that Corp's routing table shows no RIP routes- because R1 isnt advertising any. R1 doesnt have any networks
in the 10.0.0.0 range that Corp could reach
To further clarify this, we'll proceed with the book's instructions. We'll now set more RIP routes on R1
R1(config)#
router rip
R1(config-router)#
network 192.168.10.0
R1(config-router)#
network 192.168.20.0
Corp routing table before RIP set on R1:
Corp#
show ip route
10.0.0.0/8 is variably subnetted, 10 subnets, 2 masks
C 10.1.1.0/24 is directly connected, Vlan1
L 10.1.1.1/32 is directly connected, Vlan1
C 10.1.2.0/24 is directly connected, Serial0/0/0
L 10.1.2.1/32 is directly connected, Serial0/0/0
C 10.1.3.0/24 is directly connected, Serial0/0/1
L 10.1.3.1/32 is directly connected, Serial0/0/1
C 10.1.4.0/24 is directly connected, Serial0/1/0
L 10.1.4.1/32 is directly connected, Serial0/1/0
C 10.1.5.0/24 is directly connected, FastEthernet0/0
L 10.1.5.1/32 is directly connected, FastEthernet0/0
172.16.0.0/24 is subnetted, 1 subnets
S 172.16.10.0/24 [150/0] via 10.1.5.2
S 192.168.10.0/24 [150/0] via 10.1.2.2
S 192.168.20.0/24 [150/0] via 10.1.3.2
S 192.168.30.0/24 [150/0] via 10.1.4.2
S 192.168.40.0/24 [150/0] via 10.1.4.2
Corp routing table after RIP set on R1:
Gateway of last resort is not set
10.0.0.0/8 is variably subnetted, 10 subnets, 2 masks
C 10.1.1.0/24 is directly connected, Vlan1
L 10.1.1.1/32 is directly connected, Vlan1
C 10.1.2.0/24 is directly connected, Serial0/0/0
L 10.1.2.1/32 is directly connected, Serial0/0/0
C 10.1.3.0/24 is directly connected, Serial0/0/1
L 10.1.3.1/32 is directly connected, Serial0/0/1
C 10.1.4.0/24 is directly connected, Serial0/1/0
L 10.1.4.1/32 is directly connected, Serial0/1/0
C 10.1.5.0/24 is directly connected, FastEthernet0/0
L 10.1.5.1/32 is directly connected, FastEthernet0/0
nothing changed so far
172.16.0.0/24 is subnetted, 1 subnets
S 172.16.10.0/24 [150/0] via 10.1.5.2
no change
R 192.168.10.0/24 [120/1] via 10.1.2.2, 00:00:08, Serial0/0/0
[120/1] via 10.1.3.2, 00:00:08, Serial0/0/1
RIP overrides static- 2 paths available now
R 192.168.20.0/24 [120/1] via 10.1.2.2, 00:00:08, Serial0/0/0
[120/1] via 10.1.3.2, 00:00:08, Serial0/0/1
RIP overrides static- 2 paths available now
S 192.168.30.0/24 [150/0] via 10.1.4.2
no change
S 192.168.40.0/24 [150/0] via 10.1.4.2
no change
"Hi Corp- I'm R1 and I have zero networks
that fall inside 10.0.0.0, however I do have some networks that fall within
192.168.20.0 and 192.168.10.0
and you can reach them through me(R1) if you ingress at .1.2.2 or .1.3.2"
ok, we have the concept down. Time to proceed and set up RIP on R2............
R2(config)#
router rip
R2(config-router)#
network 10.0.0.0
R2(config-router)#
network 192.168.30.0
R2(config-router)#
network 192.168.40.0
R2 before RIP enabled
R2#
show ip route
10.0.0.0/24 is subnetted, 5 subnets
S 10.1.1.0 [150/0] via 10.1.4.1
S 10.1.2.0 [150/0] via 10.1.4.1
S 10.1.3.0 [150/0] via 10.1.4.1
C 10.1.4.0 is directly connected, Serial0/0/0
S 10.1.5.0 [150/0] via 10.1.4.1
172.16.0.0/24 is subnetted, 1 subnets
S 172.16.10.0 [150/0] via 10.1.4.1
S 192.168.10.0/24 [150/0] via 10.1.4.1
S 192.168.20.0/24 [150/0] via 10.1.4.1
C 192.168.30.0/24 is directly connected, FastEthernet0/0
C 192.168.40.0/24 is directly connected, FastEthernet0/1
R2 after RIP added
R2#
show ip route
10.0.0.0/24 is subnetted, 5 subnets
R 10.1.1.0 [120/1] via 10.1.4.1, 00:00:24, Serial0/0/0
from corp
R 10.1.2.0 [120/1] via 10.1.4.1, 00:00:24, Serial0/0/0
from corp
R 10.1.3.0 [120/1] via 10.1.4.1, 00:00:24, Serial0/0/0
from corp
C 10.1.4.0 is directly connected, Serial0/0/0
R 10.1.5.0 [120/1] via 10.1.4.1, 00:00:24, Serial0/0/0
from corp
172.16.0.0/24 is subnetted, 1 subnets
S 172.16.10.0 [150/0] via 10.1.4.1
R 192.168.10.0/24 [120/2] via 10.1.4.1, 00:00:24, Serial0/0/0
from R1 via corp
R 192.168.20.0/24 [120/2] via 10.1.4.1, 00:00:24, Serial0/0/0
from R1 via corp
C 192.168.30.0/24 is directly connected, FastEthernet0/0
C 192.168.40.0/24 is directly connected, FastEthernet0/1
now lets compare the Corp and R1 routing tables- before RIP was set on R2 and after
Corp before R2 RIP
Corp#
show ip route
10.0.0.0/8 is variably subnetted, 10 subnets, 2 masks
C 10.1.1.0/24 is directly connected, Vlan1
L 10.1.1.1/32 is directly connected, Vlan1
C 10.1.2.0/24 is directly connected, Serial0/0/0
L 10.1.2.1/32 is directly connected, Serial0/0/0
C 10.1.3.0/24 is directly connected, Serial0/0/1
L 10.1.3.1/32 is directly connected, Serial0/0/1
C 10.1.4.0/24 is directly connected, Serial0/1/0
L 10.1.4.1/32 is directly connected, Serial0/1/0
C 10.1.5.0/24 is directly connected, FastEthernet0/0
L 10.1.5.1/32 is directly connected, FastEthernet0/0
172.16.0.0/24 is subnetted, 1 subnets
S 172.16.10.0/24 [150/0] via 10.1.5.2
R 192.168.10.0/24 [120/1] via 10.1.2.2, 00:00:02, Serial0/0/0
[120/1] via 10.1.3.2, 00:00:02, Serial0/0/1
R 192.168.20.0/24 [120/1] via 10.1.2.2, 00:00:02, Serial0/0/0
[120/1] via 10.1.3.2, 00:00:02, Serial0/0/1
from R1
S 192.168.30.0/24 [150/0] via 10.1.4.2
S 192.168.40.0/24 [150/0] via 10.1.4.2
Corp after R2 RIP
Corp#
show ip route
10.0.0.0/8 is variably subnetted, 10 subnets, 2 masks
C 10.1.1.0/24 is directly connected, Vlan1
L 10.1.1.1/32 is directly connected, Vlan1
C 10.1.2.0/24 is directly connected, Serial0/0/0
L 10.1.2.1/32 is directly connected, Serial0/0/0
C 10.1.3.0/24 is directly connected, Serial0/0/1
L 10.1.3.1/32 is directly connected, Serial0/0/1
C 10.1.4.0/24 is directly connected, Serial0/1/0
L 10.1.4.1/32 is directly connected, Serial0/1/0
C 10.1.5.0/24 is directly connected, FastEthernet0/0
L 10.1.5.1/32 is directly connected, FastEthernet0/0
172.16.0.0/24 is subnetted, 1 subnets
S 172.16.10.0/24 [150/0] via 10.1.5.2
R 192.168.10.0/24 [120/1] via 10.1.2.2, 00:00:19, Serial0/0/0
[120/1] via 10.1.3.2, 00:00:19, Serial0/0/1
R 192.168.20.0/24 [120/1] via 10.1.2.2, 00:00:19, Serial0/0/0
[120/1] via 10.1.3.2, 00:00:19, Serial0/0/1
from R1
R 192.168.30.0/24 [120/1] via 10.1.4.2, 00:00:15, Serial0/1/0
R 192.168.40.0/24 [120/1] via 10.1.4.2, 00:00:15, Serial0/1/0
from R2
RIP on R2 is advertising .30.0 and .40.0 to Corp
R1 before R2 RIP
R1#
show ip route
10.0.0.0/24 is subnetted, 5 subnets
R 10.1.1.0 [120/1] via 10.1.2.1, 00:00:05, Serial0/0/0
[120/1] via 10.1.3.1, 00:00:05, Serial0/0/1
from Corp
C 10.1.2.0 is directly connected, Serial0/0/0
C 10.1.3.0 is directly connected, Serial0/0/1
R 10.1.4.0 [120/1] via 10.1.2.1, 00:00:05, Serial0/0/0
[120/1] via 10.1.3.1, 00:00:05, Serial0/0/1
R 10.1.5.0 [120/1] via 10.1.2.1, 00:00:05, Serial0/0/0
[120/1] via 10.1.3.1, 00:00:05, Serial0/0/1
from Corp
172.16.0.0/24 is subnetted, 1 subnets
S 172.16.10.0 [150/0] via 10.1.3.1
C 192.168.10.0/24 is directly connected, FastEthernet0/0
C 192.168.20.0/24 is directly connected, FastEthernet0/1
S 192.168.30.0/24 [150/0] via 10.1.3.1
S 192.168.40.0/24 [150/0] via 10.1.2.1
R1 after R2 RIP
R1#
show ip route
10.0.0.0/24 is subnetted, 5 subnets
R 10.1.1.0 [120/1] via 10.1.2.1, 00:00:06, Serial0/0/0
[120/1] via 10.1.3.1, 00:00:06, Serial0/0/1
from Corp
C 10.1.2.0 is directly connected, Serial0/0/0
C 10.1.3.0 is directly connected, Serial0/0/1
R 10.1.4.0 [120/1] via 10.1.2.1, 00:00:06, Serial0/0/0
[120/1] via 10.1.3.1, 00:00:06, Serial0/0/1
R 10.1.5.0 [120/1] via 10.1.2.1, 00:00:06, Serial0/0/0
[120/1] via 10.1.3.1, 00:00:06, Serial0/0/1
from Corp
172.16.0.0/24 is subnetted, 1 subnets
S 172.16.10.0 [150/0] via 10.1.3.1
C 192.168.10.0/24 is directly connected, FastEthernet0/0
C 192.168.20.0/24 is directly connected, FastEthernet0/1
R 192.168.30.0/24 [120/2] via 10.1.3.1, 00:00:06, Serial0/0/1
[120/2] via 10.1.2.1, 00:00:06, Serial0/0/0
R 192.168.40.0/24 [120/2] via 10.1.2.1, 00:00:06, Serial0/0/0
[120/2] via 10.1.3.1, 00:00:06, Serial0/0/1
from R2 via Corp
Now to set RIP on R3
R3(config)#
router rip
R3(config-router)#
network 10.0.0.0
R3(config-router)#
network 172.16.0.0
note that R3 is our only router with "gateway of last resort" set because we set a default route instead of static routes
As a result, we only see directly connected routes listed, along with a single "S*" for the default gateway
R3 before RIP
R3#
show ip route
Gateway of last resort is 10.1.5.1 to network 0.0.0.0
10.0.0.0/8 is variably subnetted, 2 subnets, 2 masks
C 10.1.5.0/24 is directly connected, FastEthernet0/0
L 10.1.5.2/32 is directly connected, FastEthernet0/0
172.16.0.0/16 is variably subnetted, 2 subnets, 2 masks
C 172.16.10.0/24 is directly connected, Dot11Radio0/0/0
L 172.16.10.1/32 is directly connected, Dot11Radio0/0/0
S* 0.0.0.0/0 [1/0] via 10.1.5.1
R3 after RIP
R3#
show ip route
Gateway of last resort is 10.1.5.1 to network 0.0.0.0
-------------------------------------------------------------
10.0.0.0/8 is variably subnetted, 6 subnets, 2 masks
R 10.1.1.0/24 [120/1] via 10.1.5.1, 00:00:21, FastEthernet0/0
R 10.1.2.0/24 [120/1] via 10.1.5.1, 00:00:21, FastEthernet0/0
R 10.1.3.0/24 [120/1] via 10.1.5.1, 00:00:21, FastEthernet0/0
R 10.1.4.0/24 [120/1] via 10.1.5.1, 00:00:21, FastEthernet0/0
from Corp
C 10.1.5.0/24 is directly connected, FastEthernet0/0
L 10.1.5.2/32 is directly connected, FastEthernet0/0
-------------------------------------------------------------
172.16.0.0/16 is variably subnetted, 2 subnets, 2 masks
C 172.16.10.0/24 is directly connected, Dot11Radio0/0/0
L 172.16.10.1/32 is directly connected, Dot11Radio0/0/0
R 192.168.10.0/24 [120/2] via 10.1.5.1, 00:00:21, FastEthernet0/0
R 192.168.20.0/24 [120/2] via 10.1.5.1, 00:00:21, FastEthernet0/0
From R1 via Corp
R 192.168.30.0/24 [120/2] via 10.1.5.1, 00:00:21, FastEthernet0/0
R 192.168.40.0/24 [120/2] via 10.1.5.1, 00:00:21, FastEthernet0/0
From R2 via Corp
S* 0.0.0.0/0 [1/0] via 10.1.5.1
Corp before R3 RIP
Corp#
show ip route
10.0.0.0/8 is variably subnetted, 10 subnets, 2 masks
C 10.1.1.0/24 is directly connected, Vlan1
L 10.1.1.1/32 is directly connected, Vlan1
C 10.1.2.0/24 is directly connected, Serial0/0/0
L 10.1.2.1/32 is directly connected, Serial0/0/0
C 10.1.3.0/24 is directly connected, Serial0/0/1
L 10.1.3.1/32 is directly connected, Serial0/0/1
C 10.1.4.0/24 is directly connected, Serial0/1/0
L 10.1.4.1/32 is directly connected, Serial0/1/0
C 10.1.5.0/24 is directly connected, FastEthernet0/0
L 10.1.5.1/32 is directly connected, FastEthernet0/0
172.16.0.0/24 is subnetted, 1 subnets
S 172.16.10.0/24 [150/0] via 10.1.5.2
R 192.168.10.0/24 [120/1] via 10.1.2.2, 00:00:26, Serial0/0/0
[120/1] via 10.1.3.2, 00:00:26, Serial0/0/1
R 192.168.20.0/24 [120/1] via 10.1.2.2, 00:00:26, Serial0/0/0
[120/1] via 10.1.3.2, 00:00:26, Serial0/0/1
from R1 via corp
R 192.168.30.0/24 [120/1] via 10.1.4.2, 00:00:21, Serial0/1/0
R 192.168.40.0/24 [120/1] via 10.1.4.2, 00:00:21, Serial0/1/0
from R2 via corp
Corp after R3 RIP
Corp#
show ip route
10.0.0.0/8 is variably subnetted, 10 subnets, 2 masks
C 10.1.1.0/24 is directly connected, Vlan1
L 10.1.1.1/32 is directly connected, Vlan1
C 10.1.2.0/24 is directly connected, Serial0/0/0
L 10.1.2.1/32 is directly connected, Serial0/0/0
C 10.1.3.0/24 is directly connected, Serial0/0/1
L 10.1.3.1/32 is directly connected, Serial0/0/1
C 10.1.4.0/24 is directly connected, Serial0/1/0
L 10.1.4.1/32 is directly connected, Serial0/1/0
C 10.1.5.0/24 is directly connected, FastEthernet0/0
L 10.1.5.1/32 is directly connected, FastEthernet0/0
172.16.0.0/16 is variably subnetted, 2 subnets, 2 masks
R 172.16.0.0/16 [120/1] via 10.1.5.2, 00:00:13, FastEthernet0/0
S 172.16.10.0/24 [150/0] via 10.1.5.2
from R3
R 192.168.10.0/24 [120/1] via 10.1.3.2, 00:00:13, Serial0/0/1
[120/1] via 10.1.2.2, 00:00:13, Serial0/0/0
R 192.168.20.0/24 [120/1] via 10.1.3.2, 00:00:13, Serial0/0/1
[120/1] via 10.1.2.2, 00:00:13, Serial0/0/0
from R1 via corp
R 192.168.30.0/24 [120/1] via 10.1.4.2, 00:00:24, Serial0/1/0
R 192.168.40.0/24 [120/1] via 10.1.4.2, 00:00:24, Serial0/1/0
from R2 via corp
R2 before R3 RIP
R2#
show ip route
10.0.0.0/24 is subnetted, 5 subnets
R 10.1.1.0 [120/1] via 10.1.4.1, 00:00:15, Serial0/0/0
R 10.1.2.0 [120/1] via 10.1.4.1, 00:00:15, Serial0/0/0
R 10.1.3.0 [120/1] via 10.1.4.1, 00:00:15, Serial0/0/0
from Corp
C 10.1.4.0 is directly connected, Serial0/0/0
R 10.1.5.0 [120/1] via 10.1.4.1, 00:00:15, Serial0/0/0
from Corp
172.16.0.0/24 is subnetted, 1 subnets
S 172.16.10.0 [150/0] via 10.1.4.1
R 192.168.10.0/24 [120/2] via 10.1.4.1, 00:00:15, Serial0/0/0
R 192.168.20.0/24 [120/2] via 10.1.4.1, 00:00:15, Serial0/0/0
from R1 via Corp
C 192.168.30.0/24 is directly connected, FastEthernet0/0
C 192.168.40.0/24 is directly connected, FastEthernet0/1
R2 after R3 RIP
R2#
show ip route
10.0.0.0/24 is subnetted, 5 subnets
R 10.1.1.0 [120/1] via 10.1.4.1, 00:00:20, Serial0/0/0
R 10.1.2.0 [120/1] via 10.1.4.1, 00:00:20, Serial0/0/0
R 10.1.3.0 [120/1] via 10.1.4.1, 00:00:20, Serial0/0/0
from Corp
C 10.1.4.0 is directly connected, Serial0/0/0
R 10.1.5.0 [120/1] via 10.1.4.1, 00:00:20, Serial0/0/0
from Corp
172.16.0.0/16 is variably subnetted, 2 subnets, 2 masks
R 172.16.0.0/16 [120/2] via 10.1.4.1, 00:00:20, Serial0/0/0
S 172.16.10.0/24 [150/0] via 10.1.4.1
from R3 via Corp
R 192.168.10.0/24 [120/2] via 10.1.4.1, 00:00:20, Serial0/0/0
R 192.168.20.0/24 [120/2] via 10.1.4.1, 00:00:20, Serial0/0/0
from R1 via Corp
C 192.168.30.0/24 is directly connected, FastEthernet0/0
C 192.168.40.0/24 is directly connected, FastEthernet0/1
R1 before R3 RIP
R1#
show ip route
10.0.0.0/24 is subnetted, 5 subnets
R 10.1.1.0 [120/1] via 10.1.2.1, 00:00:04, Serial0/0/0
[120/1] via 10.1.3.1, 00:00:04, Serial0/0/1
C 10.1.2.0 is directly connected, Serial0/0/0
C 10.1.3.0 is directly connected, Serial0/0/1
R 10.1.4.0 [120/1] via 10.1.2.1, 00:00:04, Serial0/0/0
[120/1] via 10.1.3.1, 00:00:04, Serial0/0/1
R 10.1.5.0 [120/1] via 10.1.2.1, 00:00:04, Serial0/0/0
[120/1] via 10.1.3.1, 00:00:04, Serial0/0/1
from Corp
172.16.0.0/24 is subnetted, 1 subnets
S 172.16.10.0 [150/0] via 10.1.3.1
C 192.168.10.0/24 is directly connected, FastEthernet0/0
C 192.168.20.0/24 is directly connected, FastEthernet0/1
R 192.168.30.0/24 [120/2] via 10.1.2.1, 00:00:04, Serial0/0/0
[120/2] via 10.1.3.1, 00:00:04, Serial0/0/1
R 192.168.40.0/24 [120/2] via 10.1.2.1, 00:00:04, Serial0/0/0
[120/2] via 10.1.3.1, 00:00:04, Serial0/0/1
from R2 via Corp
R1 after R3 RIP
R1#
show ip route
10.0.0.0/24 is subnetted, 5 subnets
R 10.1.1.0 [120/1] via 10.1.3.1, 00:00:03, Serial0/0/1
[120/1] via 10.1.2.1, 00:00:03, Serial0/0/0
C 10.1.2.0 is directly connected, Serial0/0/0
C 10.1.3.0 is directly connected, Serial0/0/1
R 10.1.4.0 [120/1] via 10.1.3.1, 00:00:03, Serial0/0/1
[120/1] via 10.1.2.1, 00:00:03, Serial0/0/0
R 10.1.5.0 [120/1] via 10.1.3.1, 00:00:03, Serial0/0/1
[120/1] via 10.1.2.1, 00:00:03, Serial0/0/0
from Corp
172.16.0.0/16 is variably subnetted, 2 subnets, 2 masks
R 172.16.0.0/16 [120/2] via 10.1.3.1, 00:00:03, Serial0/0/1
[120/2] via 10.1.2.1, 00:00:03, Serial0/0/0
S 172.16.10.0/24 [150/0] via 10.1.3.1
from R3 via Corp
C 192.168.10.0/24 is directly connected, FastEthernet0/0
C 192.168.20.0/24 is directly connected, FastEthernet0/1
R 192.168.30.0/24 [120/2] via 10.1.3.1, 00:00:03, Serial0/0/1
[120/2] via 10.1.2.1, 00:00:03, Serial0/0/0
R 192.168.40.0/24 [120/2] via 10.1.3.1, 00:00:03, Serial0/0/1
[120/2] via 10.1.2.1, 00:00:03, Serial0/0/0
from R2 via Corp
Verifying Configurations
in addition to
show ip route
we can also use
show ip protocols
and
debug rip ip
Corp#
show ip protocols
Routing Protocol is "rip"
Sending updates every 30 seconds, next due in 11 seconds
Invalid after 180 seconds, hold down 180, flushed after 240
Outgoing update filter list for all interfaces is not set
Incoming update filter list for all interfaces is not set
Redistributing: rip
Default version control: send version 1, receive any version
Interface Send Recv Triggered RIP Key-chain
Vlan1 1 2 1
FastEthernet0/0 1 2 1
Serial0/0/1 1 2 1
Serial0/1/0 1 2 1
Serial0/0/0 1 2 1
Automatic network summarization is in effect
Maximum path: 4
Routing for Networks:
10.0.0.0
Passive Interface(s):
Routing Information Sources:
Gateway Distance Last Update
10.1.5.2 120 00:00:00
10.1.3.2 120 00:00:10
10.1.2.2 120 00:00:10
10.1.4.2 120 00:00:20
Distance: (default is 120)
R3#
debug ip rip
R3#RIP: received v1 update from 10.1.5.1 on FastEthernet0/0
10.1.1.0 in 1 hops
10.1.2.0 in 1 hops
10.1.3.0 in 1 hops
10.1.4.0 in 1 hops
192.168.10.0 in 2 hops
192.168.20.0 in 2 hops
192.168.30.0 in 2 hops
192.168.40.0 in 2 hops
R3#RIP: sending v1 update to 255.255.255.255 via Dot11Radio0/0/0 (172.16.10.1)
RIP: build update entries
network 10.0.0.0 metric 1
network 192.168.10.0 metric 3
network 192.168.20.0 metric 3
network 192.168.30.0 metric 3
network 192.168.40.0 metric 3
RIP: sending v1 update to 255.255.255.255 via FastEthernet0/0 (10.1.5.2)
RIP: build update entries
network 172.16.0.0 metric 1
output loops until manually disabled..............
R3#
undebug all
All possible debugging has been turned off
Note that due to the Split Horizon rule, R3 is not sending all of it's known RIP data to Corp.
It is sending all known RIP data out of the wifi interface (even there though there's no router that way),
but it is ONLY sending data about the wifi network back to Corp; data that Corp doesnt already have
Now lets look at some examples with sample routers..
I got hung up on these two examples because I found the
wording to be a bit confusing. Also there was subnetting involved that I was able to figure out, but threw me at first
First source of confusion- we have two seperate examples, and I was mixing them up.
The examples are:
Use the debug ip rip command to both:
discover a problem
and figure out how RIP was configured on a router from a different sample network
The conclusion regarding 'figuring out how RIP is configured' on this router, is that RIP networks are set as 10.0.0.0 and 172.16.0.0.
We determined that we are not the 'first source' of info on the 192.168.1.0 nertwork, since it is a metric of 2. We are sending out RIP data on that network,
but that RIP data is made availbale to us via another router.
I also got tripped up on the fact that RA is sending out S0/0 which corresponds 10.0.8.1,
and then receiving on the same interface S0/0 from an ip address of 10.0.15.0 on the other side of the link
I was able to determine that these two address are actually on the same subnet. My initial assumption was that the network address for the link is 10.0.0.0.
The problem doesn't give the subnet mask- I guessed it as /20 by using a 16 block since we can see that the third octet seems to move in 8's
if the network starts at 10.0.0.0 and we use /20 with 16 block, we would indeed have a last host address of 10.0.15.254, so 10.0.15.2 would be a valid host.
So there was a twist to this problem which needed subnetting to solve. It wasnt particulary releveant to the subject of RIP, but I was curious why the address on
the other side of that link looked so strange.
The problem also points out that we can determine there are 'at least' two routers participating in RIP here since we are sending RIP data out two interfaces but
only receiving RIP data on one interface. I'm unclear on why its worded this way; we know we are a RIP router- the fact that we are receiving data on one interface
would suggest there is 'at least one more' RIP router out there.
that's it for this example. Back to the original statement-
Use the debug ip rip command to both discover a problem and figure out
how RIP was configured on a router from a different sample network
We just 'figured out how RIP was configured on a router'.. The second example is regarding 'discovering a problem', although it is mentioned first.
The second example will use debug ip rip and show ip route to find a problem with the network
it looks like RIP data for 172.16.20.0 was received on S0/0, and then that interface was bumped out of the routing table entry for that network in favor of a static route.
ok, moving on now to RIP V2
RIP V2
enable it on all four routers
Corp(config)
router rip
Corp(config-router)
version 2
R1(config)
router rip
R1(config-router)
version 2
R2(config)
router rip
R2(config-router)
version 2
R3(config)
router rip
R3(config-router)
version 2
We'll use R1 to compare RIPv1 and RIPv2
RIPv1
R1(config)
debug ip rip
R1#RIP: sending v1 update to 255.255.255.255 via FastEthernet0/0 (192.168.10.1)
RIP: build update entries
network 10.0.0.0 metric 1
network 172.16.0.0 metric 3
network 192.168.20.0 metric 1
network 192.168.30.0 metric 3
network 192.168.40.0 metric 3
RIP: sending v1 update to 255.255.255.255 via FastEthernet0/1 (192.168.20.1)
RIP: build update entries
network 10.0.0.0 metric 1
network 172.16.0.0 metric 3
network 192.168.10.0 metric 1
network 192.168.30.0 metric 3
network 192.168.40.0 metric 3
RIP: sending v1 update to 255.255.255.255 via Serial0/0/0 (10.1.2.2)
RIP: build update entries
network 10.1.3.0 metric 1
network 192.168.10.0 metric 1
network 192.168.20.0 metric 1
RIP: sending v1 update to 255.255.255.255 via Serial0/0/1 (10.1.3.2)
RIP: build update entries
network 10.1.2.0 metric 1
network 192.168.10.0 metric 1
network 192.168.20.0 metric 1
RIPv2
R1(config)
debug ip rip
R1#RIP: sending v2 update to 224.0.0.9 via FastEthernet0/0 (192.168.10.1)
RIP: build update entries
10.0.0.0/8 via 0.0.0.0, metric 1, tag 0
172.16.0.0/16 via 0.0.0.0, metric 3, tag 0
192.168.20.0/24 via 0.0.0.0, metric 1, tag 0
192.168.30.0/24 via 0.0.0.0, metric 3, tag 0
192.168.40.0/24 via 0.0.0.0, metric 3, tag 0
RIP: sending v2 update to 224.0.0.9 via FastEthernet0/1 (192.168.20.1)
RIP: build update entries
10.0.0.0/8 via 0.0.0.0, metric 1, tag 0
172.16.0.0/16 via 0.0.0.0, metric 3, tag 0
192.168.10.0/24 via 0.0.0.0, metric 1, tag 0
192.168.30.0/24 via 0.0.0.0, metric 3, tag 0
192.168.40.0/24 via 0.0.0.0, metric 3, tag 0
RIP: sending v2 update to 224.0.0.9 via Serial0/0/0 (10.1.2.2)
RIP: build update entries
10.1.3.0/24 via 0.0.0.0, metric 1, tag 0
192.168.10.0/24 via 0.0.0.0, metric 1, tag 0
192.168.20.0/24 via 0.0.0.0, metric 1, tag 0
RIP: sending v2 update to 224.0.0.9 via Serial0/0/1 (10.1.3.2)
RIP: build update entries
10.1.2.0/24 via 0.0.0.0, metric 1, tag 0
192.168.10.0/24 via 0.0.0.0, metric 1, tag 0
192.168.20.0/24 via 0.0.0.0, metric 1, tag 0
R1(config)
show ip protocols
Routing Protocol is "rip"
Sending updates every 30 seconds, next due in 13 seconds
Invalid after 180 seconds, hold down 180, flushed after 240
Outgoing update filter list for all interfaces is not set
Incoming update filter list for all interfaces is not set
Redistributing: rip
Default version control: send version 2, receive 2
Interface Send Recv Triggered RIP Key-chain
FastEthernet0/0 2 2
FastEthernet0/1 2 2
Serial0/0/0 2 2
Serial0/0/1 2 2
Automatic network summarization is in effect
Maximum path: 4
Routing for Networks:
10.0.0.0
192.168.10.0
192.168.20.0
Passive Interface(s):
Routing Information Sources:
Gateway Distance Last Update
10.1.3.1 120 00:00:21
10.1.2.1 120 00:00:21
Distance: (default is 120)
final task of this chapter
Enable a default route out to the internet , and advertise via RIP
R3(config)#
interface s0/1/0 (this is only for example, so I am not adding a serial card to R3)
R3(config-if)#
ip addr 172.16.10.5 255.255.255.252
R3(config-if)#
exit
R3(config)#
ip route 0.0.0.0 0.0.0.0 s0/0
R3(config)#
ip default-network 172.16.0.0 tells other routers via RIP that default WAN route is through R3
Chapter 8 Exam Essentials IP Routing
1. Describe the Basic IP routing process
frame changes at each hop, but packet doesnt change EXCEPT that the TTL field in the IP header decrements
2. List the information required by a router to successfully route packets
destination IP address, location of other routers, possible routers to all remote networks,
the best route to each network, how to maintain and maintain routing info
3. Describe how MAC addresses are used during the routing process
a MAC will never pass a router interface. MACs will change between router interfaces
4. View and interpret the routing table of a router
use show ip route to see the table
a "C" indicates directly connected, an "R" indicates RIP provided the route info, "S" means static
5. differentiate the three types of routing
static- manually configured
dynamic- routers automatically share info via protocol
default- a special route is configured for all traffic without a more specific destination network found in the table
6. Compare and contrast static and dynamic routing
static routing creates no routing update traffic which means less overhead on the routers and links- but it must be
configured manually and can't react if links are lost.
dynamic routing creates update traffic, but it can react to outages and choose the best route when multiple routes exist to the same network
7. Configure static routes at the CLI
route [dest network] [mask] [next hop address OR exit interface] [admin distance] [permanent]
Ex:
Corp(config)#
ip route 192.168.10.0 255.255.255.0 10.1.2.2 150
8. Create a default route
ip route 0.0.0.0 0.0.0.0 [ip address OR exit interface]
Ex:
R3(config)#
ip route 0.0.0.0 0.0.0.0 10.1.5.1 (ingress at Corp router- use if R3 cant identify route)
9. Understand administrative distance and its role in the selection of the best route
an integer from 0 (most trusted) to 255 (no traffic will pass via this route).
All routing protocols are assigned an AD but it can be changed at the CLI
10. Differentiate distance-vector, link-state, and hybrid routing protocols
distance vector- based on hop count (RIP)
link-state- multiple factors such as bandwidth and delay
hybrid- uses both
11. List mechanisms used to prevent routing loops in the network
max hop count, split horizon, route poisoning, holddown counters
12. Describe the counts used the operation of RIP
route update timer- (30) interval between routing updates
route invalid timer- (180, update x 3) before a route is determined invalid
holddown timer-(180) time info is supressed when a link is lost
route flush timer- (240) seconds before invalid and removal
13. Configure RIP routing
router rip
network x.x.x.x
the network(s) you want to advertise from your router. It only works if the other router has RIP enabled.
By enabling RIP, you are able to RECEIVE RIP data from other RIP routers.
by specifying a network, you are SENDING RIP data on that network
14. Identify commands used to verify RIP routing
show ip route will provide contents of the routing table with codes (R, C, S)
debug ip rip will show RIP updates being sent and received
15. Describe the differences between RIPv1 and RIPv2
RIPv1 sends a broadcast (255.255.255.255) every 30 seconds and has an AD of 120.
RIPv1 is classful only, does not send any mask info. No authentication between routers.
RIPv2 sends multicasts (224.0.0.9) every 30 seconds and sends mask info, which allows it to support classless networking, RIPv2 also supports
autentication between routers.
Chapter 8 Written Lab 8.0
1. At the appropriate prompt, create a static route to network 172.16.10.0/24 with a next-hop
gateway of 172.16.20.1 and an administrative distance of 150.
Router(config)#
ip route 172.16.10.0 255.255.255.0 172.16.20.1 150
2. When a PC sends a packet to another PC in a remote network, what destination IP address and MAC address will
be in the frame that it sends to it's default gateway?
the gateway interface MAC and the remote PC's IP
3. At the appropriate prompt, create a default route to 172.16.40.1
Router(config)#
ip route 0.0.0.0 0.0.0.0 172.16.40.1
"to" is the wrong word.. we are going TO any route VIA 172.16.40.1
4. If you are using default routing in a classless environment, what command must also be used?
Router(config)#
ip classless
5. On which type of network is a default route most beneficial?
stub
6. At the appropriate prompt, display the routing table on your router
Router#
show ip route
7. When creating a static or default route, you dont have to use the next-hop ip address;
you can instead use the ____________
exit interface
8. True/False: To reach a destination host, you must know the MAC address of the remote host
false, you need the MAC of your router
9. True/False: To reach a destination host, you must know the IP address of the remote host
true
10. At the appropriate prompt, execute the command required on a DCE serial interface that is not required
on a DTE serial interface
Router(config-if)#
clock rate X
11. At the appropriate prompt, enable RIP routing on the interface with the IP address 10.0.0.1/24
Router(config)#
router rip
Router(config-router)#
network 10.0.0.0
RIPv1 is CLASSFUL only... use the classful mask based on the first octet given
12. At the appropriate prompt, prevent a router from propagating IP information out serial 1
Router(config)#
router rip
Router(config-router)#
passive-interface S0/1
can receive RIP data but will not send
13. What routing loop prevention mechanism sends out a maximum hop count as soon as a link fails?
route poisoning
14. What routing loop prevention mechanism suppresses the resending of routing information to an interface
through which it was received?
split horizon
15. At the appropriate prompt display RIP routing updates as they are sent and received on the router
to the console session
Router#
debug ip rip
to turn it off:
Router#
undebug all
Chapter 8 Hands-on Labs
For these labs we will need a network with three routers.
Lab 8.1 Creating Static routes
first set the interfaces, then program the static routes
LabA(config)#
int s0/0/0
LabA(config-if)#
ip addr 172.16.20.1
LabA(config-if)#
int f0/0
LabA(config-if)#
ip addr 172.16.10.1
-----------------------------------------------------------------
LabA(config)#
ip route 172.16.30.0 255.255.255.0 172.16.20.2
LabA(config)#
ip route 172.16.40.0 255.255.255.0 172.16.20.2
LabB(config)#
int s0/0/0
LabB(config-if)#
ip addr 172.16.20.2
LabB(config-if)#
int s0/0/1
LabB(config-if)#
ip addr 172.16.30.1
-----------------------------------------------------------------
LabB(config)#
ip route 172.16.10.0 255.255.255.0 172.16.20.1
LabB(config)#
ip route 172.16.40.0 255.255.255.0 172.16.30.2
LabC(config)#
int s0/0/0
LabC(config-if)#
ip addr 172.16.30.2
LabC(config-if)#
int f0/0
LabC(config-if)#
ip addr 172.16.40.1
-----------------------------------------------------------------
LabC(config)#
ip route 172.16.10.0 255.255.255.0 172.16.30.1
LabC(config)#
ip route 172.16.20.0 255.255.255.0 172.16.30.1
Lab 8.2 RIP Configuration
remove the static routes, enable and configure RIP with the classful network id that covers the routes you want to advertise
LabA(config)#
no ip route 172.16.30.0 255.255.255.0 172.16.20.2
LabA(config)#
no ip route 172.16.40.0 255.255.255.0 172.16.20.2
LabA(config)#
router rip
LabA(config-router)#
network 172.16.0.0
LabA(config-router)#
do show ip route
Gateway of last resort is not set
172.16.0.0/16 is variably subnetted, 5 subnets, 2 masks
C 172.16.10.0/24 is directly connected, FastEthernet0/0
L 172.16.10.1/32 is directly connected, FastEthernet0/0
C 172.16.20.0/24 is directly connected, Serial0/0/0
L 172.16.20.1/32 is directly connected, Serial0/0/0
R 172.16.30.0/24 [120/1] via 172.16.20.2, 00:00:07, Serial0/0/0
from Lab B
LabB(config)#
no ip route 172.16.10.0 255.255.255.0 172.16.20.1
LabB(config)#
no ip route 172.16.40.0 255.255.255.0 172.16.30.2
LabB(config)#
router rip
LabB(config-router)#
network 172.16.0.0
LabB(config-router)#
do show ip route
Gateway of last resort is not set
172.16.0.0/16 is variably subnetted, 5 subnets, 2 masks
R 172.16.10.0/24 [120/1] via 172.16.20.1, 00:00:13, Serial0/0/0
from LabA
C 172.16.20.0/24 is directly connected, Serial0/0/0
L 172.16.20.2/32 is directly connected, Serial0/0/0
C 172.16.30.0/24 is directly connected, Serial0/0/1
L 172.16.30.1/32 is directly connected, Serial0/0/1
LabC(config)#
no ip route 172.16.10.0 255.255.255.0 172.16.30.1
LabC(config)#
no ip route 172.16.20.0 255.255.255.0 172.16.30.1
LabC(config)#
router rip
LabC(config-router)#
network 172.16.0.0
LabC(config-router)#
do show ip route
Gateway of last resort is not set
172.16.0.0/16 is variably subnetted, 3 subnets, 2 masks
R 172.16.20.0/24 [120/1] via 172.16.30.1, 00:00:05, Serial0/0/0
from LabB
C 172.16.30.0/24 is directly connected, Serial0/0/0
L 172.16.30.2/32 is directly connected, Serial0/0/0
Chapter 8 Review Questions
1. The Acme company uses a router named Gateway to connect to its ISP. The address of the ISP router is 206.143.5.2.
Which three commands could be configured on the gateway router to allow internet access to the entire network?
Set a default route:
Gateway(config)#
ip route 0.0.0.0 0.0.0.0 206.143.5.2 next hop IP
Gateway(config)#
ip route 0.0.0.0 0.0.0.0 S/0 exit interface instead of next hop IP
Gateway(config)#
ip default-network 206.143.5.0 next hop IP
2. What command will prevent RIP routing updates from exiting an interface but will sill allow the interface to receive RIP updates?
Router(config-if)#
passive-interface
3. Which two statemnts are true about ip route 172.16.4.0 255.255.255.0 192.168.4.2?
the command establishes a static route
the default admin distance is used (since we didnt give an AD argument)
4. What two destination addresses will be used by HostA to send data to the HTTPS server as shown in the following network?
MAC of RouterA f0/0 interface
IP address of the server
5. Which two statements are true about this output?
RIP: received v1 update from 192.168.40.2 on S0/1
192.168.50.0 in 16 hops (inaccessible)
RIP: sending v1 update to 255.255.255.255 via F0/0 (192.168.30.1)
RIP: build update entries
network 192.168.20.0 metric 1
network 192.168.40.0 metric 1
network 192.168.50.0 metric 16
RIP: sending v1 update to 255.255.255.255 via S0/1 (192.168.40.1)
true:
there are at least two routers exchanging information
192.168.40.2 will be successful
FALSE
there are three interfaces on the router participating in this update
false because we only see two interfaces represented in the output: S0/1(twice) and F0/0
a ping to 192.168.50.1 will be successful
false because that route has a metric of 16; it's unreachable
6. Describe split horizon
will not advertise a route back the the same router it was learned from
7. Which would be true if HostA is trying to communicate to HostB and interface F0/0 of RouterC goes down, as shown in the graphic?
RouterC will send an ICMP 'destination unreachable type' message to inform HostA that HostB is unreachable
8. Which two statements are true regarding classless routing protocols?
VLSM is permitted
RIPv2 supports classless
9. Which two are true regarding distance-vector vs link-state?
Distance vector sends the whole routing table out all active interfaces(even if a router isnt on the other end)at periodic time intervals
Link-state sends updates containing the state of its own links to all routers in the inter-network
10. Which command display RIP routing updates?
debug ip rip
11. What does RIPv2 use to prvent routing loops?
split horizon stops an update from being send on the same interface it was received
holdown timers allow time for a network to become stable in the case of a flapping link
12. A network administrator views the output from the show ip route command. A network that is advertised
by both RIP and EIGRP appears in the routing table flagged an EIGRP route. Why is the RIP route to this network not used in this routing table?
EIGRP has a lower AD.
RIP=120
OSPP=110
IGRP=110
EIGRP=90
13. You type debug ip rip on your router console and see that 172.16.10.0 is being advertised to you with a metric of 16. What does this mean?
it is inaccessible. in RIP if you see a route advertised with a metric of 16, it's inaccessible
14. What metric does RIPv2 use to find the best path to the remote network?
distance aka hop count
15. The Corporate router receives an IP packet with a source IP address of 192.168.214.20 and a destination address of 192.168.22.3. Looking at the output from the Corp router,
what will the router do with this packet?
Corp# show ip route
[cut]
R 192.168.215.0 [120/2] via 192.168.20.2, Serail0/0
R 192.168.115.0 [120/1] via 192.168.20.0, Serial0/0
R 192.168.30.0 [120/1] via 192.168.20.2, Serial0/0
C 192.168.20.0 is directly connected, Serial0/0
C 192.168.214.0 is directly connected, FastEthernet0/0
Since there is no route to that network, the router will discard the packet and send an ICMP destination unreachable message out F0/0 back the the source network
16. If your routing table has a static, a RIP and an EIGRP route to the same network, which route will be used by default?
Static routes have an admin distance of 1 by default. Unless you change it, a static route will always be used over any other
dynamically learned route.
17. You have the following routing table. Which network will NOT be placed in the neighbor routing table?
R 192.168.30.0/24 [120/1] via 192.168.40.1, Serial 0
C 192.168.40.0/24 is directly connected, Serial 0
172.16.0.0/2 is subnetted, 1 subnets
C 172.16.30.0 is directly connected, Loopback0
R 192.168.20.0/24 [120/1] via 192.168.40.1, Serial 0
R 10.0.0.0/8 [120/15] via 192.168.40.1, Serial 0
C 192.168.50.0/24 is directly connected, Ethernet 0
10.0.0.0 cant be placed in neighboring routing table because it is at 15 hops. 16 hops is invalid in RIP
18. Two connected routers are configured only with RIP. What will be the result when a router receives a routing update that contains a
higher-cost path to a network already in it's routing table?
The router will ignore the update because it is higher cost. When a routing update is received, the router first checks the AD and always chooses
the route with the lowest AD.
19.Which is true about route poisoning?
The router sets the metric for a downed link to "infinity".
20. Which is true about RIPv2?
it has all the same timers as RIPv1
------------------------------------------------------------------------------
END CHAPTER 8
54 hours 1-28 thru 2-14-22
original total 143 hours
11.5 hours review 12-23,24,26-22
review total hours 32
book page 428/822
avg 20 min/page (reading and exercises/labs)
Chapter 9 EIGRP and OSPF
pages 427-502, start 2-14-22-M
What is EIGRP?
Note it's not officially on CCNA 200-301 but it is still important to learn
Enhanced IGRP is a classless, enchanced distance vector protocol that uses the concept of an autonomous system to describe
the set of contigous routers that run the same routing protocol and share routing information.
Features:
Support for IP and IPv6 via protocol-dependent modules (seperate routing tables)
Considered classless
Support for summaries and discontiguous networks
Eficient neighbor discovery
communication via RTP- Reliable Transport Protocol
best path selection via Diffusing Updae Algorithm DUAL
Cisco considers EIGRP a "distance-vector" routing protocol
or an "advanced distance-vector" protocol
or a "hybrid" protocol
Configuring EIGRP on our network
------------------------------------------------------------------------------------------------------------------------------------
Corp(config)#
router eigrp ?
<1-65535> Autonomous system number
Corp(config)#
router eigrp 10
R2(config-router)#
network 10.0.0.0
after eigrp on R1- links from Corp to R1 are up
%DUAL-5-NBRCHANGE: IP-EIGRP 10: Neighbor 10.1.3.2 (Serial0/0/1) is up: new adjacency
%DUAL-5-NBRCHANGE: IP-EIGRP 10: Neighbor 10.1.2.2 (Serial0/0/0) is up: new adjacency
after eigrp on R2- link from Corp to R2 is up
%DUAL-5-NBRCHANGE: IP-EIGRP 10: Neighbor 10.1.4.2 (Serial0/1/0) is up: new adjacency
after eigrp on R3- link from Corp to R3 is up
%DUAL-5-NBRCHANGE: IP-EIGRP 10: Neighbor 10.1.5.2 (FastEthernet0/0) is up: new adjacency
------------------------------------------------------------------------------------------------------------------------------------
R1(config)#
router eigrp 10
R1(config-router)#
network 10.0.0.0
after eigrp on R1- link from R1 to Corp is up
%DUAL-5-NBRCHANGE: IP-EIGRP 10: Neighbor 10.1.3.1 (Serial0/0/1) is up: new adjacency
%DUAL-5-NBRCHANGE: IP-EIGRP 10: Neighbor 10.1.2.1 (Serial0/0/0) is up: new adjacency
R1(config-router)#
network 192.168.10.0
R1(config-router)#
network 192.168.20.0
------------------------------------------------------------------------------------------------------------------------------------
R2(config)#
router eigrp 10
R2(config-router)#
network 10.0.0.0
after eigrp on R2- link from R2 to Corp is up
%DUAL-5-NBRCHANGE: IP-EIGRP 10: Neighbor 10.1.4.1 (Serial0/0/0) is up: new adjacency
R1(config-router)#
network 192.168.30.0
R1(config-router)#
network 192.168.40.0
------------------------------------------------------------------------------------------------------------------------------------
R3(config)#
router eigrp 10
R3(config-router)#
network 10.0.0.0
after eigrp on R3- link from R3 to Corp is up
%DUAL-5-NBRCHANGE: IP-EIGRP 10: Neighbor 10.1.5.1 (FastEthernet0/0) is up: new adjacency
R1(config-router)#
network 172.16.0.0
------------------------------------------------------------------------------------------------------------------------------------
Corp#
show ip route
Gateway of last resort is not set
Gateway of last resort is not set
10.0.0.0/8 is variably subnetted, 10 subnets, 2 masks
C 10.1.1.0/24 is directly connected, Vlan1
L 10.1.1.1/32 is directly connected, Vlan1
C 10.1.2.0/24 is directly connected, Serial0/0/0
L 10.1.2.1/32 is directly connected, Serial0/0/0
C 10.1.3.0/24 is directly connected, Serial0/0/1
L 10.1.3.1/32 is directly connected, Serial0/0/1
C 10.1.4.0/24 is directly connected, Serial0/1/0
L 10.1.4.1/32 is directly connected, Serial0/1/0
C 10.1.5.0/24 is directly connected, FastEthernet0/0
L 10.1.5.1/32 is directly connected, FastEthernet0/0
172.16.0.0/16 is variably subnetted, 2 subnets, 2 masks
R 172.16.0.0/16 [120/1] via 10.1.5.2, 00:00:17, FastEthernet0/0
D 172.16.10.0/24 [90/28160] via 10.1.5.2, 00:00:16, FastEthernet0/0
via R3
D 192.168.10.0/24 [90/2172416] via 10.1.2.2, 00:19:13, Serial0/0/0
[90/2172416] via 10.1.3.2, 00:19:13, Serial0/0/1
D 192.168.20.0/24 [90/2172416] via 10.1.3.2, 00:19:05, Serial0/0/1
[90/2172416] via 10.1.2.2, 00:19:05, Serial0/0/0
via R1
D 192.168.30.0/24 [90/2172416] via 10.1.4.2, 00:01:31, Serial0/1/0
D 192.168.40.0/24 [90/2172416] via 10.1.4.2, 00:01:08, Serial0/1/0
via R2
The "D" routes are for DUAL- Diffusing Update Algorithm, indicating they are EIGRP routes.
Note that we have RIP and EIGRP set currently
------------------------------------------------------------------------------------------------------------------------------------
R1#
show ip route
Gateway of last resort is not set
10.0.0.0/8 is variably subnetted, 6 subnets, 2 masks
D 10.0.0.0/8 is a summary, 00:25:28, Null0
D 10.1.1.0/24 [90/27769856] via 10.1.2.1, 00:31:33, Serial0/0/0
[90/27769856] via 10.1.3.1, 00:31:30, Serial0/0/1
via Corp
C 10.1.2.0/24 is directly connected, Serial0/0/0
C 10.1.3.0/24 is directly connected, Serial0/0/1
D 10.1.4.0/24 [90/2681856] via 10.1.2.1, 00:31:33, Serial0/0/0
[90/2681856] via 10.1.3.1, 00:31:30, Serial0/0/1
D 10.1.5.0/24 [90/2172416] via 10.1.2.1, 00:31:33, Serial0/0/0
[90/2172416] via 10.1.3.1, 00:31:30, Serial0/0/1
via Corp
172.16.0.0/16 is variably subnetted, 2 subnets, 2 masks
R 172.16.0.0/16 [120/2] via 10.1.2.1, 00:00:07, Serial0/0/0
[120/2] via 10.1.3.1, 00:00:07, Serial0/0/1
D 172.16.10.0/24 [90/2172416] via 10.1.2.1, 00:06:31, Serial0/0/0
[90/2172416] via 10.1.3.1, 00:06:31, Serial0/0/1
via Corp
C 192.168.10.0/24 is directly connected, FastEthernet0/0
C 192.168.20.0/24 is directly connected, FastEthernet0/1
D 192.168.30.0/24 [90/2684416] via 10.1.3.1, 00:07:46, Serial0/0/1
[90/2684416] via 10.1.2.1, 00:07:46, Serial0/0/0
D 192.168.40.0/24 [90/2684416] via 10.1.2.1, 00:07:23, Serial0/0/0
[90/2684416] via 10.1.3.1, 00:07:23, Serial0/0/1
via Corp
------------------------------------------------------------------------------------------------------------------------------------
R2#
show ip route
Gateway of last resort is not set
10.0.0.0/8 is variably subnetted, 6 subnets, 2 masks
D 10.0.0.0/8 is a summary, 00:13:09, Null0
D 10.1.1.0/24 [90/27769856] via 10.1.4.1, 00:36:53, Serial0/0/0
D 10.1.2.0/24 [90/2681856] via 10.1.4.1, 00:36:53, Serial0/0/0
D 10.1.3.0/24 [90/2681856] via 10.1.4.1, 00:36:53, Serial0/0/0
via Corp
C 10.1.4.0/24 is directly connected, Serial0/0/0
D 10.1.5.0/24 [90/2172416] via 10.1.4.1, 00:36:53, Serial0/0/0
via Corp
172.16.0.0/16 is variably subnetted, 2 subnets, 2 masks
R 172.16.0.0/16 [120/2] via 10.1.4.1, 00:00:23, Serial0/0/0
D 172.16.10.0/24 [90/2172416] via 10.1.4.1, 00:11:54, Serial0/0/0
via Corp
D 192.168.10.0/24 [90/2684416] via 10.1.4.1, 00:30:51, Serial0/0/0
D 192.168.20.0/24 [90/2684416] via 10.1.4.1, 00:30:43, Serial0/0/0
via Corp
C 192.168.30.0/24 is directly connected, FastEthernet0/0
C 192.168.40.0/24 is directly connected, FastEthernet0/1
------------------------------------------------------------------------------------------------------------------------------------
R3#
show ip route
Gateway of last resort is 10.1.5.1 to network 0.0.0.0
10.0.0.0/8 is variably subnetted, 6 subnets, 2 masks
D 10.1.1.0/24 [90/25628160] via 10.1.5.1, 00:37:20, FastEthernet0/0
D 10.1.2.0/24 [90/2172416] via 10.1.5.1, 00:37:15, FastEthernet0/0
D 10.1.3.0/24 [90/2172416] via 10.1.5.1, 00:37:20, FastEthernet0/0
D 10.1.4.0/24 [90/2172416] via 10.1.5.1, 00:37:20, FastEthernet0/0
via Corp
C 10.1.5.0/24 is directly connected, FastEthernet0/0
L 10.1.5.2/32 is directly connected, FastEthernet0/0
172.16.0.0/16 is variably subnetted, 2 subnets, 2 masks
C 172.16.10.0/24 is directly connected, Dot11Radio0/0/0
L 172.16.10.1/32 is directly connected, Dot11Radio0/0/0
D 192.168.10.0/24 [90/2174976] via 10.1.5.1, 00:31:10, FastEthernet0/0
D 192.168.20.0/24 [90/2174976] via 10.1.5.1, 00:31:02, FastEthernet0/0
via Corp and R1
D 192.168.30.0/24 [90/2174976] via 10.1.5.1, 00:13:28, FastEthernet0/0
D 192.168.40.0/24 [90/2174976] via 10.1.5.1, 00:13:05, FastEthernet0/0
via Corp and R2
S* 0.0.0.0/0 [1/0] via 10.1.5.1
------------------------------------------------------------------------------------------------------------------------------------
turn off auto summary on each router
------------------------------------------------------------------------------------------------------------------------------------
Corp(config)#
router eigrp 10
Corp(config-router)#
no auto-summary
------------------------------------------------------------------------------------------------------------------------------------
R1(config)#
router eigrp 10
R1(config-router)#
no auto-summary
------------------------------------------------------------------------------------------------------------------------------------
R2(config)#
router eigrp 10
R2(config-router)#
no auto-summary
------------------------------------------------------------------------------------------------------------------------------------
R3(config)#
router eigrp 10
R3(config-router)#
no auto-summary
------------------------------------------------------------------------------------------------------------------------------------
compare Corp before and after auto summary turned off
------------------------------------------------------------------------------------------------------------------------------------
auto summary on
Corp#
show ip route
Gateway of last resort is not set
10.0.0.0/8 is variably subnetted, 10 subnets, 2 masks
C 10.1.1.0/24 is directly connected, Vlan1
L 10.1.1.1/32 is directly connected, Vlan1
C 10.1.2.0/24 is directly connected, Serial0/0/0
L 10.1.2.1/32 is directly connected, Serial0/0/0
C 10.1.3.0/24 is directly connected, Serial0/0/1
L 10.1.3.1/32 is directly connected, Serial0/0/1
C 10.1.4.0/24 is directly connected, Serial0/1/0
L 10.1.4.1/32 is directly connected, Serial0/1/0
C 10.1.5.0/24 is directly connected, FastEthernet0/0
L 10.1.5.1/32 is directly connected, FastEthernet0/0
172.16.0.0/16 is variably subnetted, 2 subnets, 2 masks
R 172.16.0.0/16 [120/1] via 10.1.5.2, 00:00:17, FastEthernet0/0
D 172.16.10.0/24 [90/28160] via 10.1.5.2, 00:00:16, FastEthernet0/0
via R3
D 192.168.10.0/24 [90/2172416] via 10.1.2.2, 00:19:13, Serial0/0/0
[90/2172416] via 10.1.3.2, 00:19:13, Serial0/0/1
D 192.168.20.0/24 [90/2172416] via 10.1.3.2, 00:19:05, Serial0/0/1
[90/2172416] via 10.1.2.2, 00:19:05, Serial0/0/0
via R1
D 192.168.30.0/24 [90/2172416] via 10.1.4.2, 00:01:31, Serial0/1/0
D 192.168.40.0/24 [90/2172416] via 10.1.4.2, 00:01:08, Serial0/1/0
via R2
auto summary off
Corp#
show ip route
Gateway of last resort is not set
10.0.0.0/8 is variably subnetted, 10 subnets, 2 masks
C 10.1.1.0/24 is directly connected, Vlan1
L 10.1.1.1/32 is directly connected, Vlan1
C 10.1.2.0/24 is directly connected, Serial0/0/0
L 10.1.2.1/32 is directly connected, Serial0/0/0
C 10.1.3.0/24 is directly connected, Serial0/0/1
L 10.1.3.1/32 is directly connected, Serial0/0/1
C 10.1.4.0/24 is directly connected, Serial0/1/0
L 10.1.4.1/32 is directly connected, Serial0/1/0
C 10.1.5.0/24 is directly connected, FastEthernet0/0
L 10.1.5.1/32 is directly connected, FastEthernet0/0
172.16.0.0/16 is variably subnetted, 2 subnets, 2 masks
R 172.16.0.0/16 [120/1] via 10.1.5.2, 00:00:12, FastEthernet0/0
D 172.16.10.0/24 [90/28160] via 10.1.5.2, 00:45:29, FastEthernet0/0
via R3
D 192.168.10.0/24 [90/2172416] via 10.1.2.2, 00:01:08, Serial0/0/0
[90/2172416] via 10.1.3.2, 00:01:08, Serial0/0/1
D 192.168.20.0/24 [90/2172416] via 10.1.2.2, 00:01:08, Serial0/0/0
[90/2172416] via 10.1.3.2, 00:01:08, Serial0/0/1
via R1
D 192.168.30.0/24 [90/2172416] via 10.1.4.2, 00:00:46, Serial0/1/0
D 192.168.40.0/24 [90/2172416] via 10.1.4.2, 00:00:46, Serial0/1/0
via R2
We are still seeing an auto summarized route- 172.16.0.0 coming from R3.
The book discusses enabling EIGRP auto summary on all four routers- nothing is said about disabling it within RIP or turning off RIP.
RIP auto summarizes by default. We cant get rid of this auto summary route while RIP is on.
Moving on...
VERIFYING EIGRP
several commands available to verify and troubleshoot
show ip route
show the entire routing table
show ip route eigrp
show only EIGRP entries in the routing table
show ip eigrp neighbors
show all EIGRP neigbors
show ip eigrp topology
show entries in the EIGRP topology table
show ip protocols
shows routing protocols configuration
debug eigrp packet
shows hello packets sent/received between adjacent routers
debug ip eigrp events
shows EIGRP changes and updates as they occur on your network
lets take a look at the state of our 4 routers. RIP and EIGRP are running on each.
Notice how this command is giving different outputs between the two different IOS versions
IOS 15.1
Corp#
show ip protocols
Routing Protocol is "eigrp 10 "
Outgoing update filter list for all interfaces is not set
Incoming update filter list for all interfaces is not set
Default networks flagged in outgoing updates
Default networks accepted from incoming updates
Redistributing: eigrp 10
EIGRP-IPv4 Protocol for AS(10)
Metric weight K1=1, K2=0, K3=1, K4=0, K5=0
NSF-aware route hold timer is 240
Router-ID: 10.1.1.1
Topology : 0 (base)
Active Timer: 3 min
Distance: internal 90 external 170
Maximum path: 4
Maximum hopcount 100
Maximum metric variance 1
Automatic Summarization: disabled
Automatic address summarization:
Maximum path: 4
Routing for Networks:
10.0.0.0
Routing Information Sources:
Gateway Distance Last Update
10.1.5.2 90 0
10.1.3.2 90 6464
10.1.2.2 90 6795
10.1.4.2 90 7955
Distance: internal 90 external 170
Routing Protocol is "rip"
Sending updates every 30 seconds, next due in 10 seconds
Invalid after 180 seconds, hold down 180, flushed after 240
Outgoing update filter list for all interfaces is not set
Incoming update filter list for all interfaces is not set
Redistributing: rip
Default version control: send version 2, receive 2
Interface Send Recv Triggered RIP Key-chain
Vlan1 2 2
FastEthernet0/0 2 2
Serial0/1/0 2 2
Serial0/0/1 2 2
Serial0/0/0 2 2
Automatic network summarization is in effect
Maximum path: 4
Routing for Networks:
10.0.0.0
Passive Interface(s):
Routing Information Sources:
Gateway Distance Last Update
10.1.5.2 120 00:00:12
10.1.3.2 120 00:00:16
10.1.2.2 120 00:00:16
10.1.4.2 120 00:00:13
Distance: (default is 120)
IOS 12.4
R1#
show ip protocols
Routing Protocol is "eigrp 10 "
Outgoing update filter list for all interfaces is not set
Incoming update filter list for all interfaces is not set
Default networks flagged in outgoing updates
Default networks accepted from incoming updates
EIGRP metric weight K1=1, K2=0, K3=1, K4=0, K5=0
EIGRP maximum hopcount 100
EIGRP maximum metric variance 1
Redistributing: eigrp 10
Automatic network summarization is not in effect
Maximum path: 4
Routing for Networks:
10.0.0.0
192.168.10.0
192.168.20.0
Routing Information Sources:
Gateway Distance Last Update
10.1.3.1 90 6465
10.1.2.1 90 6794
Distance: internal 90 external 170
Routing Protocol is "rip"
Sending updates every 30 seconds, next due in 21 seconds
Invalid after 180 seconds, hold down 180, flushed after 240
Outgoing update filter list for all interfaces is not set
Incoming update filter list for all interfaces is not set
Redistributing: rip
Default version control: send version 2, receive 2
Interface Send Recv Triggered RIP Key-chain
FastEthernet0/0 2 2
FastEthernet0/1 2 2
Serial0/0/0 2 2
Serial0/0/1 2 2
Automatic network summarization is not in effect
Maximum path: 4
Routing for Networks:
10.0.0.0
192.168.10.0
192.168.20.0
Passive Interface(s):
Routing Information Sources:
Gateway Distance Last Update
10.1.3.1 120 00:00:06
10.1.2.1 120 00:00:06
Distance: (default is 120)
IOS 12.4
R2#
show ip protocols
Routing Protocol is "eigrp 10 "
Outgoing update filter list for all interfaces is not set
Incoming update filter list for all interfaces is not set
Default networks flagged in outgoing updates
Default networks accepted from incoming updates
EIGRP metric weight K1=1, K2=0, K3=1, K4=0, K5=0
EIGRP maximum hopcount 100
EIGRP maximum metric variance 1
Redistributing: eigrp 10
Automatic network summarization is not in effect
Maximum path: 4
Routing for Networks:
10.0.0.0
192.168.30.0
192.168.40.0
Routing Information Sources:
Gateway Distance Last Update
10.1.4.1 90 7955
Distance: internal 90 external 170
Routing Protocol is "rip"
Sending updates every 30 seconds, next due in 11 seconds
Invalid after 180 seconds, hold down 180, flushed after 240
Outgoing update filter list for all interfaces is not set
Incoming update filter list for all interfaces is not set
Redistributing: rip
Default version control: send version 2, receive 2
Interface Send Recv Triggered RIP Key-chain
FastEthernet0/0 2 2
FastEthernet0/1 2 2
Serial0/0/0 2 2
Automatic network summarization is in effect
Maximum path: 4
Routing for Networks:
10.0.0.0
192.168.30.0
192.168.40.0
Passive Interface(s):
Routing Information Sources:
Gateway Distance Last Update
10.1.4.1 120 00:00:20
Distance: (default is 120)
IOS 15.1
R3#
show ip protocols
Routing Protocol is "eigrp 10 "
Outgoing update filter list for all interfaces is not set
Incoming update filter list for all interfaces is not set
Default networks flagged in outgoing updates
Default networks accepted from incoming updates
Redistributing: eigrp 10
EIGRP-IPv4 Protocol for AS(10)
Metric weight K1=1, K2=0, K3=1, K4=0, K5=0
NSF-aware route hold timer is 240
Router-ID: 10.1.5.2
Topology : 0 (base)
Active Timer: 3 min
Distance: internal 90 external 170
Maximum path: 4
Maximum hopcount 100
Maximum metric variance 1
Automatic Summarization: disabled
Automatic address summarization:
Maximum path: 4
Routing for Networks:
10.0.0.0
172.16.0.0
Routing Information Sources:
Gateway Distance Last Update
10.1.5.1 90 0
Distance: internal 90 external 170
Routing Protocol is "rip"
Sending updates every 30 seconds, next due in 27 seconds
Invalid after 180 seconds, hold down 180, flushed after 240
Outgoing update filter list for all interfaces is not set
Incoming update filter list for all interfaces is not set
Redistributing: rip
Default version control: send version 2, receive 2
Interface Send Recv Triggered RIP Key-chain
Dot11Radio0/0/0 2 2
FastEthernet0/0 2 2
Automatic network summarization is not in effect
Maximum path: 4
Routing for Networks:
10.0.0.0
172.16.0.0
Passive Interface(s):
Routing Information Sources:
Gateway Distance Last Update
10.1.5.1 120 00:00:02
Distance: (default is 120)
I'm also noticing that we have inconsistent auto-summarization settings- I was having trouble with this earlier. The book discusses
getting rid of the 172.16.0.0 summarized route in the EIGRP settings. I was not able to get rid of it, I think because RIP is still on, and RIP forces auto-summary
Part of the challenge here is that the book is strictly dealing with IOS 12.4
I will now make sure to turn auto summary off for both RIP and EIGRP on each of the four routers.
OK the part I am forgetting is that we are running RIP V2 which does not force auto-summary but runs it optionally, and we must turn it off to avoid auto summarization.
Corp(config)#
router rip
Corp(config-router)#
no auto-summary
Corp(config-router)#
router eigrp 10
Corp(config-router)#
no auto-summary
R1(config)#
router rip
R1(config-router)#
no auto-summary
R1(config-router)#
router eigrp 10
R1(config-router)#
no auto-summary
R1(config)#
router rip
R1(config-router)#
no auto-summary
R1(config-router)#
router eigrp 10
R2(config-router)#
no auto-summary
R3(config)#
router rip
R3(config-router)#
no auto-summary
R3(config-router)#
router eigrp 10
R3(config-router)#
no auto-summary
and lets see how the output looks now. This time I'll do show ip protocols and
show ip route side by side for each router
IOS 15.1
Corp#
show ip protocols
Routing Protocol is "eigrp 10 "
Outgoing update filter list for all interfaces is not set
Incoming update filter list for all interfaces is not set
Default networks flagged in outgoing updates
Default networks accepted from incoming updates
Redistributing: eigrp 10
EIGRP-IPv4 Protocol for AS(10)
Metric weight K1=1, K2=0, K3=1, K4=0, K5=0
NSF-aware route hold timer is 240
Router-ID: 10.1.1.1
Topology : 0 (base)
Active Timer: 3 min
Distance: internal 90 external 170
Maximum path: 4
Maximum hopcount 100
Maximum metric variance 1
Automatic Summarization: disabled
Automatic address summarization:
Maximum path: 4
Routing for Networks:
10.0.0.0
Routing Information Sources:
Gateway Distance Last Update
10.1.5.2 90 0
10.1.3.2 90 6464
10.1.2.2 90 6795
10.1.4.2 90 7955
Distance: internal 90 external 170
Routing Protocol is "rip" doesnt necessarily mean RIPv1
Sending updates every 30 seconds, next due in 3 seconds
Invalid after 180 seconds, hold down 180, flushed after 240
Outgoing update filter list for all interfaces is not set
Incoming update filter list for all interfaces is not set
Redistributing: rip
Default version control: send version 2, receive 2 RIPv2 is specified
Interface Send Recv Triggered RIP Key-chain
Vlan1 2 2
FastEthernet0/0 2 2
Serial0/1/0 2 2
Serial0/0/1 2 2
Serial0/0/0 2 2
Automatic network summarization is not in effect
Maximum path: 4
Routing for Networks:
10.0.0.0
Passive Interface(s):
Routing Information Sources:
Gateway Distance Last Update
10.1.5.2 120 00:00:02
10.1.3.2 120 00:00:21
10.1.2.2 120 00:00:21
10.1.4.2 120 00:00:04
Distance: (default is 120)
IOS 15.1
Corp#
show ip route
Gateway of last resort is not set
10.0.0.0/8 is variably subnetted, 10 subnets, 2 masks
C 10.1.1.0/24 is directly connected, Vlan1
L 10.1.1.1/32 is directly connected, Vlan1
C 10.1.2.0/24 is directly connected, Serial0/0/0
L 10.1.2.1/32 is directly connected, Serial0/0/0
C 10.1.3.0/24 is directly connected, Serial0/0/1
L 10.1.3.1/32 is directly connected, Serial0/0/1
C 10.1.4.0/24 is directly connected, Serial0/1/0
L 10.1.4.1/32 is directly connected, Serial0/1/0
C 10.1.5.0/24 is directly connected, FastEthernet0/0
L 10.1.5.1/32 is directly connected, FastEthernet0/0
172.16.0.0/24 is subnetted, 1 subnets
D 172.16.10.0/24 [90/28160] via 10.1.5.2, 00:57:25, FastEthernet0/0
D 192.168.10.0/24 [90/2172416] via 10.1.3.2, 00:57:20, Serial0/0/1
[90/2172416] via 10.1.2.2, 00:57:20, Serial0/0/0
D 192.168.20.0/24 [90/2172416] via 10.1.3.2, 00:57:20, Serial0/0/1
[90/2172416] via 10.1.2.2, 00:57:20, Serial0/0/0
D 192.168.30.0/24 [90/2172416] via 10.1.4.2, 00:57:19, Serial0/1/0
D 192.168.40.0/24 [90/2172416] via 10.1.4.2, 00:57:19, Serial0/1/0
IOS 12.4
R1#
show ip protocols
Routing Protocol is "eigrp 10 "
Outgoing update filter list for all interfaces is not set
Incoming update filter list for all interfaces is not set
Default networks flagged in outgoing updates
Default networks accepted from incoming updates
EIGRP metric weight K1=1, K2=0, K3=1, K4=0, K5=0
EIGRP maximum hopcount 100
EIGRP maximum metric variance 1
Redistributing: eigrp 10
Automatic network summarization is not in effect
Maximum path: 4
Routing for Networks:
10.0.0.0
192.168.10.0
192.168.20.0
Routing Information Sources:
Gateway Distance Last Update
10.1.3.1 90 6465
10.1.2.1 90 6794
Distance: internal 90 external 170
Routing Protocol is "rip"
Sending updates every 30 seconds, next due in 26 seconds
Invalid after 180 seconds, hold down 180, flushed after 240
Outgoing update filter list for all interfaces is not set
Incoming update filter list for all interfaces is not set
Redistributing: rip
Default version control: send version 2, receive 2
Interface Send Recv Triggered RIP Key-chain
FastEthernet0/0 2 2
FastEthernet0/1 2 2
Serial0/0/0 2 2
Serial0/0/1 2 2
Automatic network summarization is not in effect
Maximum path: 4
Routing for Networks:
10.0.0.0
192.168.10.0
192.168.20.0
Passive Interface(s):
Routing Information Sources:
Gateway Distance Last Update
10.1.3.1 120 00:00:03
10.1.2.1 120 00:00:03
Distance: (default is 120)
IOS 12.4
R1#
show ip route
Gateway of last resort is not set
10.0.0.0/24 is subnetted, 5 subnets
D 10.1.1.0 [90/27769856] via 10.1.3.1, 00:54:47, Serial0/0/1
[90/27769856] via 10.1.2.1, 00:54:47, Serial0/0/0
C 10.1.2.0 is directly connected, Serial0/0/0
C 10.1.3.0 is directly connected, Serial0/0/1
D 10.1.4.0 [90/2681856] via 10.1.3.1, 00:54:47, Serial0/0/1
[90/2681856] via 10.1.2.1, 00:54:47, Serial0/0/0
D 10.1.5.0 [90/2172416] via 10.1.3.1, 00:54:47, Serial0/0/1
[90/2172416] via 10.1.2.1, 00:54:47, Serial0/0/0
172.16.0.0/24 is subnetted, 1 subnets
D 172.16.10.0 [90/2172416] via 10.1.3.1, 00:54:47, Serial0/0/1
[90/2172416] via 10.1.2.1, 00:54:47, Serial0/0/0
C 192.168.10.0/24 is directly connected, FastEthernet0/0
C 192.168.20.0/24 is directly connected, FastEthernet0/1
D 192.168.30.0/24 [90/2684416] via 10.1.3.1, 00:54:46, Serial0/0/1
[90/2684416] via 10.1.2.1, 00:54:46, Serial0/0/0
D 192.168.40.0/24 [90/2684416] via 10.1.3.1, 00:54:46, Serial0/0/1
[90/2684416] via 10.1.2.1, 00:54:46, Serial0/0/0
note that the DUAL routes being advertised from the 10.0.0.0 networks are all specific to the third octet.. that's because we are reading those routes
from their source, aka the router which they are directly connected to, Corp.
and on Corp, those networks were added to the interfaces with a /24 mask.
so even though our EIGRP config doesnt specifically include /24 networks.. we told it to include anything with a 10.x.x.x
Corp is advertising to R1 our /24 network interfaces that have a 10 in the first octet, EXCEPT the two which are directly connected to R1
10.1.1.0
10.1.4.0
10.1.5.0
are assumed to be the subnets based on the info we configured, which was 10.1.4.1/24 on corp, and 10.1.4.2/24 on r2 s0/0/0
nowhere in this configuration, have we entered the 10.1.4.0 network.
EIGRP is figuring it out based on the /24 mask we gave when assiging he IPs to the interfaces
IOS 12.4
R2#
show ip protocols
Routing Protocol is "eigrp 10 "
Outgoing update filter list for all interfaces is not set
Incoming update filter list for all interfaces is not set
Default networks flagged in outgoing updates
Default networks accepted from incoming updates
EIGRP metric weight K1=1, K2=0, K3=1, K4=0, K5=0
EIGRP maximum hopcount 100
EIGRP maximum metric variance 1
Redistributing: eigrp 10
Automatic network summarization is not in effect
Maximum path: 4
Routing for Networks:
10.0.0.0
192.168.30.0
192.168.40.0
Routing Information Sources:
Gateway Distance Last Update
10.1.4.1 90 7955
Distance: internal 90 external 170
Routing Protocol is "rip"
Sending updates every 30 seconds, next due in 18 seconds
Invalid after 180 seconds, hold down 180, flushed after 240
Outgoing update filter list for all interfaces is not set
Incoming update filter list for all interfaces is not set
Redistributing: rip
Default version control: send version 2, receive 2
Interface Send Recv Triggered RIP Key-chain
FastEthernet0/0 2 2
FastEthernet0/1 2 2
Serial0/0/0 2 2
Automatic network summarization is not in effect
Maximum path: 4
Routing for Networks:
10.0.0.0
192.168.30.0
192.168.40.0
Passive Interface(s):
Routing Information Sources:
Gateway Distance Last Update
10.1.4.1 120 00:00:07
Distance: (default is 120)
IOS 12.4
R2#
show ip route
Gateway of last resort is not set
10.0.0.0/24 is subnetted, 5 subnets
D 10.1.1.0 [90/27769856] via 10.1.4.1, 00:59:10, Serial0/0/0
D 10.1.2.0 [90/2681856] via 10.1.4.1, 00:59:10, Serial0/0/0
D 10.1.3.0 [90/2681856] via 10.1.4.1, 00:59:10, Serial0/0/0
C 10.1.4.0 is directly connected, Serial0/0/0
D 10.1.5.0 [90/2172416] via 10.1.4.1, 00:59:10, Serial0/0/0
172.16.0.0/24 is subnetted, 1 subnets
D 172.16.10.0 [90/2172416] via 10.1.4.1, 00:59:10, Serial0/0/0
D 192.168.10.0/24 [90/2684416] via 10.1.4.1, 00:59:10, Serial0/0/0
D 192.168.20.0/24 [90/2684416] via 10.1.4.1, 00:59:10, Serial0/0/0
C 192.168.30.0/24 is directly connected, FastEthernet0/0
C 192.168.40.0/24 is directly connected, FastEthernet0/1
IOS 15.1
R3#
show ip protocols
Routing Protocol is "eigrp 10 "
Outgoing update filter list for all interfaces is not set
Incoming update filter list for all interfaces is not set
Default networks flagged in outgoing updates
Default networks accepted from incoming updates
Redistributing: eigrp 10
EIGRP-IPv4 Protocol for AS(10)
Metric weight K1=1, K2=0, K3=1, K4=0, K5=0
NSF-aware route hold timer is 240
Router-ID: 10.1.5.2
Topology : 0 (base)
Active Timer: 3 min
Distance: internal 90 external 170
Maximum path: 4
Maximum hopcount 100
Maximum metric variance 1
Automatic Summarization: disabled
Automatic address summarization:
Maximum path: 4
Routing for Networks:
10.0.0.0
172.16.0.0
Routing Information Sources:
Gateway Distance Last Update
10.1.5.1 90 0
Distance: internal 90 external 170
Routing Protocol is "rip"
Sending updates every 30 seconds, next due in 15 seconds
Invalid after 180 seconds, hold down 180, flushed after 240
Outgoing update filter list for all interfaces is not set
Incoming update filter list for all interfaces is not set
Redistributing: rip
Default version control: send version 2, receive 2
Interface Send Recv Triggered RIP Key-chain
Dot11Radio0/0/0 2 2
FastEthernet0/0 2 2
Automatic network summarization is not in effect
Maximum path: 4
Routing for Networks:
10.0.0.0
172.16.0.0
Passive Interface(s):
Routing Information Sources:
Gateway Distance Last Update
10.1.5.1 120 00:00:14
Distance: (default is 120)
IOS 15.1
R3#
show ip route
Gateway of last resort is 10.1.5.1 to network 0.0.0.0
10.0.0.0/8 is variably subnetted, 6 subnets, 2 masks
D 10.1.1.0/24 [90/25628160] via 10.1.5.1, 00:59:52, FastEthernet0/0
D 10.1.2.0/24 [90/2172416] via 10.1.5.1, 00:59:47, FastEthernet0/0
D 10.1.3.0/24 [90/2172416] via 10.1.5.1, 00:59:52, FastEthernet0/0
D 10.1.4.0/24 [90/2172416] via 10.1.5.1, 00:59:52, FastEthernet0/0
C 10.1.5.0/24 is directly connected, FastEthernet0/0
L 10.1.5.2/32 is directly connected, FastEthernet0/0
172.16.0.0/16 is variably subnetted, 2 subnets, 2 masks
C 172.16.10.0/24 is directly connected, Dot11Radio0/0/0
L 172.16.10.1/32 is directly connected, Dot11Radio0/0/0
D 192.168.10.0/24 [90/2174976] via 10.1.5.1, 00:59:47, FastEthernet0/0
D 192.168.20.0/24 [90/2174976] via 10.1.5.1, 00:59:47, FastEthernet0/0
D 192.168.30.0/24 [90/2174976] via 10.1.5.1, 00:59:46, FastEthernet0/0
D 192.168.40.0/24 [90/2174976] via 10.1.5.1, 00:59:46, FastEthernet0/0
S* 0.0.0.0/0 [1/0] via 10.1.5.1
Observations:
Since this is a 15.1 router, we always get a "L" local route when
we have a "C" connected route. In R3's case, the 172.16.10.0 network
is directly connected. The interface which connects it, 172.16.10.1,
counts as a "local" route. This is NOT the case on the 12.4 routers.
looking to the left, our protocol output tells us two key facts for both EIGRP and RIP:
Routing for networks:
10.0.0.0
172.16.0.0
R3 is responsible for *sending* data about these two networks to our other EIGRP routers...
"I'm R3 and I can connect you to networks on the R3
router or networks on the Corp router"
Notice how the 192 networks arent listed. R3 isnt connected to a 192 network directly, nor is it connected to a neighbor who is directly connected.
If I, as a client, am sending data to a 192 network from the 172 network, I will start
at R3. Since R3 is receiving routes for the 192 networks via Corp, I will be able to reach a 192 network via Corp.
My connection to corp will happen VIA a "10.0.0.0" route.
R3 is technically only routing for 172 and 10 networks. Beyond that, it could potentially connect to many other different networks. But in terms of the R3 routing table,
all it can offer is a path out to the 172 network or the 10 network
Routing information sources:
10.1.5.1
In this case I can see that R3 is receiving routing data from one interface only,
and that is it's link to Corp. Some of the data we are receiving from Corp actually originates
at other routers, but we cant see that here; the data comes to us from Corp, and that is all we know
EIGRP TERMINOLOGY
FEASIBLE DISTANCE (FD)
the best metric among all paths, including to the next hop neighbor. You will only see the route with the lowest FD appear in the routing table
The FD is calculated by adding the reported distance from the neighbor (AD) plus the metric to that neighbor
ADVERTISED DISTANCE (AD)
the metric of a remote network as reported by a neighbor, listed second in parenthesis in toplogy table
P 192.168.20.0/24, 2 successors, FD is 2172416
via 10.1.3.2 (2172416/28160), Serial0/0/1
feasible / advertised
Neighbor Table
each router keeps state information about adjacent neighbors.. When a new neighbor is learned, the address and interface are recorded.
The neighbor table is stored in RAM.
Sequence numbres are used to match acks with update packets. The last squence number received from a neighbor is recorded so out of order packets
can be detected
Topology Table
acted upon by DUAL Diffusing Update Alogorithm. Contains all destinations advertised by neighboring routers.
For each neighbor, the adversited distance, which comes only from that neighbor's routing table, is recorded
The feasible distance is also recorded.
Feasible Successor
a PATH whose advertised distance is less than the feasible distance of the current succesor, and is considered a backup route.
EIGRP keeps up to 16 feasible successors in the toplogy table.
The one with the best metric (The Successor) is copied and placed into the routing table
Successor
the best route to a remote network, used by EIGRP to forward traffic. It's backed up by a feasible successor, if one is available.
lets demo some more of the commands
VERIFYING EIGRP
several commands available to verify and troubleshoot
show ip route
show the entire routing table
show ip route eigrp
show only EIGRP entries in the routing table
show ip eigrp neighbors
show all EIGRP neigbors
show ip eigrp topology
show entries in the EIGRP topology table
show ip protocols
shows routing protocols configuration
debug eigrp packet
shows hello packets sent/received between adjacent routers
debug ip eigrp events
shows EIGRP changes and updates as they occur on your network
Corp#
show ip eigrp ?
interfaces IP-EIGRP interfaces
neighbors IP-EIGRP neighbors
topology IP-EIGRP Topology Table
traffic IP-EIGRP Traffic Statistics
Corp#
show ip eigrp topology
IP-EIGRP Topology Table for AS 10/ID(10.1.5.1)
Codes: P - Passive, A - Active, U - Update, Q - Query, R - Reply,
r - Reply status
P 10.1.1.0/24, 1 successors, FD is 25625600
via Connected, Vlan1
P 10.1.2.0/24, 1 successors, FD is 2169856
via Connected, Serial0/0/0
P 10.1.3.0/24, 1 successors, FD is 2169856
via Connected, Serial0/0/1
P 10.1.4.0/24, 1 successors, FD is 2169856
via Connected, Serial0/1/0
P 10.1.5.0/24, 1 successors, FD is 28160
via Connected, FastEthernet0/0
P 172.16.10.0/24, 1 successors, FD is 28160
via 10.1.5.2 (28160/25600), FastEthernet0/0
P 192.168.10.0/24, 2 successors, FD is 2172416
via 10.1.3.2 (2172416/28160), Serial0/0/1
via 10.1.2.2 (2172416/28160), Serial0/0/0
P 192.168.20.0/24, 2 successors, FD is 2172416
via 10.1.3.2 (2172416/28160), Serial0/0/1
via 10.1.2.2 (2172416/28160), Serial0/0/0
P 192.168.30.0/24, 1 successors, FD is 2172416
via 10.1.4.2 (2172416/28160), Serial0/1/0
P 192.168.40.0/24, 1 successors, FD is 2172416
via 10.1.4.2 (2172416/28160), Serial0/1/0
the "P" preceding each entry is for PASSIVE
these routes are in a passive state, which is good
if they move to an ACTIVE state, it means the have lost their path in the network and looking for a replacement.
Each entry also shows the FEASIBLE DISTANCE, the next hop address, and the local egress interface
Corp#
show ip eigrp neighbors
IP-EIGRP neighbors for process 10
H Address Interface Hold Uptime SRTT RTO Q Seq
(sec) (ms) Cnt Num
0 10.1.5.2 Fa0/0 14 02:00:05 40 1000 0 19
1 10.1.3.2 Se0/0/1 13 01:59:59 40 1000 0 14
2 10.1.2.2 Se0/0/0 13 01:59:59 40 1000 0 13
3 10.1.4.2 Se0/1/0 12 01:59:57 40 1000 0 15
fields:
H - the order in which the neighbors were discovered
hold - how long the router will wait for a hello packet
uptime - how long the neigborship has been established
SRTT - smooth round trip timer - the time it takes for a round trip from this router, to neighbor, and back.
SRTT is used to determine how long to wait for a MULTICAST reply.
if a reply isnt received in time, the router switches to UNICASTS
RTO - Retransmission Time Out- is the time EIGRP waits before retransmitting a packet from the retransmission queue
Q - indicates wheter there are oustanding messages in the queue
Seq - indicates the sequence number of the last update from that neighbor. This is used to maintain syncrhonization and avoid duplicate
or out-of-sequence processing of messages
Corp#
show ip route eigrp
172.16.0.0/24 is subnetted, 1 subnets
D 172.16.10.0 [90/28160] via 10.1.5.2, 02:08:04, FastEthernet0/0
D 192.168.10.0/24 [90/2172416] via 10.1.3.2, 02:07:59, Serial0/0/1
[90/2172416] via 10.1.2.2, 02:07:59, Serial0/0/0
D 192.168.20.0/24 [90/2172416] via 10.1.3.2, 02:07:59, Serial0/0/1
[90/2172416] via 10.1.2.2, 02:07:59, Serial0/0/0
D 192.168.30.0/24 [90/2172416] via 10.1.4.2, 02:07:58, Serial0/1/0
D 192.168.40.0/24 [90/2172416] via 10.1.4.2, 02:07:58, Serial0/1/0
Corp#
show ip eigrp interfaces
IP-EIGRP interfaces for process 10
Xmit Queue Mean Pacing Time Multicast Pending
Interface Peers Un/Reliable SRTT Un/Reliable Flow Timer Routes
Vlan 0 0/0 1236 0/10 0 0
Fa0/0 1 0/0 1236 0/10 0 0
Se0/1/0 1 0/0 1236 0/10 0 0
Se0/0/1 1 0/0 1236 0/10 0 0
Se0/0/0 1 0/0 1236 0/10 0 0
Corp#
show ip protocols
Routing Protocol is "eigrp 10 "
Outgoing update filter list for all interfaces is not set
Incoming update filter list for all interfaces is not set
Default networks flagged in outgoing updates
Default networks accepted from incoming updates
Redistributing: eigrp 10
EIGRP-IPv4 Protocol for AS(10)
Metric weight K1=1, K2=0, K3=1, K4=0, K5=0 using K1 bandwidth and K2 delay by default
NSF-aware route hold timer is 240
Router-ID: 10.1.1.1
Topology : 0 (base)
Active Timer: 3 min
Distance: internal 90 external 170
Maximum path: 4
Maximum hopcount 100
Maximum metric variance 1
Automatic Summarization: disabled
Automatic address summarization:
Maximum path: 4
Routing for Networks:
10.0.0.0
Routing Information Sources:
Gateway Distance Last Update
10.1.5.2 90 0
10.1.3.2 90 8936
10.1.4.2 90 9511
10.1.2.2 90 9597
Distance: internal 90 external 170
Routing Protocol is "rip"
Sending updates every 30 seconds, next due in 13 seconds
Invalid after 180 seconds, hold down 180, flushed after 240
Outgoing update filter list for all interfaces is not set
Incoming update filter list for all interfaces is not set
Redistributing: rip
Default version control: send version 2, receive 2
Interface Send Recv Triggered RIP Key-chain
Vlan1 2 2
FastEthernet0/0 2 2
Serial0/0/1 2 2
Serial0/1/0 2 2
Serial0/0/0 2 2
Automatic network summarization is not in effect
Maximum path: 4
Routing for Networks:
10.0.0.0
Passive Interface(s):
Routing Information Sources:
Gateway Distance Last Update
10.1.5.2 120 00:00:05
10.1.3.2 120 00:00:12
10.1.2.2 120 00:00:12
10.1.4.2 120 00:00:17
Distance: (default is 120)
corp#
debug eigrp packet
break into two columns for readability
Observations:
There doesnt appear to be a pattern in the order each router is addressed, except that the TO's and FROM"s are grouped together
The TO messages dont show the destination IP, only the egress local interface
The FROM messages do show the remote IP, as well as the local ingress interface
Corp#
EIGRP: Received HELLO on FastEthernet0/0 nbr 10.1.5.2
AS 10, Flags 0x0, Seq 18/0 idbQ 0/0
hello from R3
Corp#
EIGRP: Received HELLO on Serial0/1/0 nbr 10.1.4.2
AS 10, Flags 0x0, Seq 16/0 idbQ 0/0
hello from R2
Corp#
EIGRP: Received HELLO on Serial0/0/0 nbr 10.1.2.2
AS 10, Flags 0x0, Seq 19/0 idbQ 0/0
hello from R1
------------------------------------------------------------
Corp#
EIGRP: Sending HELLO on Serial0/1/0
AS 10, Flags 0x0, Seq 21/0 idbQ 0/0 iidbQ un/rely 0/0
hello to R2
Corp#
EIGRP: Sending HELLO on FastEthernet0/0
AS 10, Flags 0x0, Seq 21/0 idbQ 0/0 iidbQ un/rely 0/0
hello to R3
Corp#
EIGRP: Sending HELLO on Serial0/0/1
AS 10, Flags 0x0, Seq 21/0 idbQ 0/0 iidbQ un/rely 0/0
hello to R1
Corp#
EIGRP: Sending HELLO on Serial0/0/0
AS 10, Flags 0x0, Seq 21/0 idbQ 0/0 iidbQ un/rely 0/0
hello to R1
Corp#
EIGRP: Sending HELLO on Vlan1
AS 10, Flags 0x0, Seq 21/0 idbQ 0/0 iidbQ un/rely 0/0
hello to switch card (not a router....)
------------------------------------------------------------
Corp#
EIGRP: Received HELLO on Serial0/0/1 nbr 10.1.3.2
AS 10, Flags 0x0, Seq 19/0 idbQ 0/0
hello from R1
Corp#
EIGRP: Received HELLO on FastEthernet0/0 nbr 10.1.5.2
AS 10, Flags 0x0, Seq 18/0 idbQ 0/0
hello from R3
Corp#
EIGRP: Received HELLO on Serial0/0/0 nbr 10.1.2.2
AS 10, Flags 0x0, Seq 19/0 idbQ 0/0
hello from R1
Corp#
EIGRP: Received HELLO on Serial0/1/0 nbr 10.1.4.2
AS 10, Flags 0x0, Seq 16/0 idbQ 0/0
hello from R2
------------------------------------------------------------
Corp#
EIGRP: Sending HELLO on Serial0/1/0
AS 10, Flags 0x0, Seq 21/0 idbQ 0/0 iidbQ un/rely 0/0
hello to R2... no neighbor IP?
Corp#
EIGRP: Sending HELLO on Serial0/0/0
AS 10, Flags 0x0, Seq 21/0 idbQ 0/0 iidbQ un/rely 0/0
hello to R1... no neighbor IP?
Corp#
EIGRP: Sending HELLO on FastEthernet0/0
AS 10, Flags 0x0, Seq 21/0 idbQ 0/0 iidbQ un/rely 0/0
hello to R3... no neighbor IP?
Corp#
EIGRP: Sending HELLO on Serial0/0/1
AS 10, Flags 0x0, Seq 21/0 idbQ 0/0 iidbQ un/rely 0/0
hello to R1
Corp#
EIGRP: Sending HELLO on Vlan1
AS 10, Flags 0x0, Seq 21/0 idbQ 0/0 iidbQ un/rely 0/0
hello to switch card (not a router)
------------------------------------------------------------
OUTPUT CONTINUES IN NEXT COLUMN
Corp#
EIGRP: Received HELLO on Serial0/0/1 nbr 10.1.3.2
AS 10, Flags 0x0, Seq 19/0 idbQ 0/0
hello from R1
Corp#
EIGRP: Received HELLO on FastEthernet0/0 nbr 10.1.5.2
AS 10, Flags 0x0, Seq 18/0 idbQ 0/0
hello from R3
Corp#
EIGRP: Received HELLO on Serial0/0/0 nbr 10.1.2.2
AS 10, Flags 0x0, Seq 19/0 idbQ 0/0
hello from R1
Corp#
EIGRP: Received HELLO on Serial0/1/0 nbr 10.1.4.2
AS 10, Flags 0x0, Seq 16/0 idbQ 0/0
hello from R2
------------------------------------------------------------
Corp#
EIGRP: Sending HELLO on Serial0/1/0
AS 10, Flags 0x0, Seq 21/0 idbQ 0/0 iidbQ un/rely 0/0
hello to R2
Corp#
EIGRP: Sending HELLO on Serial0/0/0
AS 10, Flags 0x0, Seq 21/0 idbQ 0/0 iidbQ un/rely 0/0
hello to R1
Corp#
EIGRP: Sending HELLO on Vlan1
AS 10, Flags 0x0, Seq 21/0 idbQ 0/0 iidbQ un/rely 0/0
hello to Corp switchcard
Corp#
EIGRP: Sending HELLO on Serial0/0/1
AS 10, Flags 0x0, Seq 21/0 idbQ 0/0 iidbQ un/rely 0/0
hello to R1
Corp#
EIGRP: Sending HELLO on FastEthernet0/0
AS 10, Flags 0x0, Seq 21/0 idbQ 0/0 iidbQ un/rely 0/0
hello to R3... no neighbor IP?
------------------------------------------------------------
Corp#
EIGRP: Received HELLO on Serial0/0/1 nbr 10.1.3.2
AS 10, Flags 0x0, Seq 19/0 idbQ 0/0
hello from R1
Corp#
EIGRP: Received HELLO on FastEthernet0/0 nbr 10.1.5.2
AS 10, Flags 0x0, Seq 18/0 idbQ 0/0
hello from R3
Corp#
EIGRP: Received HELLO on Serial0/1/0 nbr 10.1.4.2
AS 10, Flags 0x0, Seq 16/0 idbQ 0/0
hello from R2
Corp#
EIGRP: Received HELLO on Serial0/0/0 nbr 10.1.2.2
AS 10, Flags 0x0, Seq 19/0 idbQ 0/0
hello from R1
------------------------------------------------------------
Corp#
EIGRP: Sending HELLO on Serial0/1/0
AS 10, Flags 0x0, Seq 21/0 idbQ 0/0 iidbQ un/rely 0/0
hello to R2
Corp#
EIGRP: Sending HELLO on Vlan1
AS 10, Flags 0x0, Seq 21/0 idbQ 0/0 iidbQ un/rely 0/0
hello to Corp switchcard
EIGRP: Sending HELLO on Serial0/0/0
AS 10, Flags 0x0, Seq 21/0 idbQ 0/0 iidbQ un/rely 0/0
hello to R1
EIGRP: Sending HELLO on Serial0/0/1
AS 10, Flags 0x0, Seq 21/0 idbQ 0/0 iidbQ un/rely 0/0
hello to R1
Corp#
EIGRP: Sending HELLO on FastEthernet0/0
AS 10, Flags 0x0, Seq 21/0 idbQ 0/0 iidbQ un/rely 0/0
hello to R3
------------------------------------------------------------
Now some videos. To reinforce EIGRP concepts, and lead into OSPF
OSPF - OPEN SHORTEST PATH FIRST
Before enabling OSPF, we'll turn off RIP and EIGRP on all four routers.
Device(config)#
no router eigrp 10
Device(config)#
no router rip
The OSPF configs for the local egress ip address
Corp(config)#
router ospf 132
Corp(config)#
network 10.1.0.0 0.0.255.255 area 0
R1(config)#
router ospf 1
R1(config)#
network 10.1.0.0 0.0.255.255 area 0
R1(config)#
network 192.168.0.0 0.0.255.255 area 0
R2(config)#
router ospf 45678
R2(config)#
network 10.0.0.0 0.0.0.255 area 0
R2(config)#
network 192.168.30.1 0.0.0.0 area 0
R2(config)#
network 192.168.40.1 0.0.0.0 area 0
all 32 bits of the mask are specified for the 192 entries;
these are not network id's, they are HOST id's of the specific interfaces, which are EGRESS interfaces on the router we are configuring
R3(config)#
router ospf 1
R2(config)#
network 10.1.5.2 0.0.0.255 area 0
R2(config)#
network 172.16.10.0 0.0.0.255 area 0
Wildcard Masks
these notes are not intended to be a precise explanation of wlidcard masking, but rather a look into my thought process as I am learning the concept.
resources:
traceroute blog examples
routerjockey blog examples
subnetonline wildcard calculator
Ch 9 Exam Essentials
1. Know EIGRP features
classless (like RipV2 and OSPF)
distance vector
supports IP, IPX, appleTalk, IPV6
supports summaries and discontiguous networks
uses the Diffusing Update Algorithm (DUAL) to maintain route information
uses RTP to communicate with other EIGRP routers
uses the concept of an autonomous system to describe the set of contiguous routers that run the same routing protocol and share routing information
considered CLASSLESS- includes the subnet mask in its route updates
sends traditional distance-vector updates containing info about networks plus the cost of reaching them from the perspective of the advertising router
but not strictly distance-vector. Has link-state characteristics: synchronizes routing tables between neighbors at startup and then sends specific updates only when topology changes.
max hop count of 255 (default is 100)
but hop count is NOT a metric, like in RIP. Hop count is how many routers an EIGRP route update can traverse before being discarded. This limits the size of the AS.
2. Know how to configure EIGRP
the router eigrp [as] command turns EIGRP routing on in the router. Unlike RIPv1, EIGRP uses classless routing. BUT you can still configure as classful.
R1(config)#
router eigrp 10
enters router config mode
R1(config-router)#
network 10.0.0.0
on this router, interfaces that fall within 10.0.0.0 will advertise EIGRP info
3. Know how to verify EIGRP operation
Corp#
show ip
protocols
Corp#
show ip
route
Corp#
show ip
route eigrp
Corp#
show ip
eigrp neighbors
Corp#
show ip
eigrp topology
Corp#
show ip
eigrp interfaces
Corp#
show ip
protocols
info about all active routing protocols
Routing Protocol is "eigrp 10 "
Outgoing update filter list for all interfaces is not set
Incoming update filter list for all interfaces is not set
Default networks flagged in outgoing updates
Default networks accepted from incoming updates
Redistributing: eigrp 10
EIGRP-IPv4 Protocol for AS(10)
Metric weight K1=1, K2=0, K3=1, K4=0, K5=0
NSF-aware route hold timer is 240
Router-ID: 10.1.1.1
Topology : 0 (base)
Active Timer: 3 min
Distance: internal 90 external 170
Maximum path: 4
Maximum hopcount 100
Maximum metric variance 1
Automatic Summarization: disabled
Automatic address summarization:
Maximum path: 4
Routing for Networks:
10.0.0.0
Routing Information Sources:
Gateway Distance Last Update
10.1.2.2 90 200105
10.1.3.2 90 200113
10.1.4.2 90 254351
10.1.5.2 90 303742
Distance: internal 90 external 170
Corp#
show ip
protocols
(continued)
Routing Protocol is "rip"
Sending updates every 30 seconds, next due in 6 seconds
Invalid after 180 seconds, hold down 180, flushed after 240
Outgoing update filter list for all interfaces is not set
Incoming update filter list for all interfaces is not set
Redistributing: rip
Default version control: send version 2, receive 2
Interface Send Recv Triggered RIP Key-chain
Vlan1 2 2
FastEthernet0/0 2 2
Serial0/1/0 2 2
Serial0/0/1 2 2
Serial0/0/0 2 2
Automatic network summarization is not in effect
Maximum path: 4
Routing for Networks:
10.0.0.0
Passive Interface(s):
Routing Information Sources:
Gateway Distance Last Update
10.1.5.2 120 00:00:15
10.1.3.2 120 00:00:01
10.1.2.2 120 00:00:01
10.1.4.2 120 00:00:17
Distance: (default is 120)
Corp#
show ip
route
entire routing table
Codes: L - local, C - connected, S - static, R - RIP, M - mobile, B - BGP
D - EIGRP, EX - EIGRP external, O - OSPF, IA - OSPF inter area
N1 - OSPF NSSA external type 1, N2 - OSPF NSSA external type 2
E1 - OSPF external type 1, E2 - OSPF external type 2, E - EGP
i - IS-IS, L1 - IS-IS level-1, L2 - IS-IS level-2, ia - IS-IS inter area
* - candidate default, U - per-user static route, o - ODR
P - periodic downloaded static route
Gateway of last resort is not set
10.0.0.0/8 is variably subnetted, 10 subnets, 2 masks
C 10.1.1.0/24 is directly connected, Vlan1
L 10.1.1.1/32 is directly connected, Vlan1
C 10.1.2.0/24 is directly connected, Serial0/0/0
L 10.1.2.1/32 is directly connected, Serial0/0/0
C 10.1.3.0/24 is directly connected, Serial0/0/1
L 10.1.3.1/32 is directly connected, Serial0/0/1
C 10.1.4.0/24 is directly connected, Serial0/1/0
L 10.1.4.1/32 is directly connected, Serial0/1/0
C 10.1.5.0/24 is directly connected, FastEthernet0/0
L 10.1.5.1/32 is directly connected, FastEthernet0/0
172.16.0.0/16 is variably subnetted, 2 subnets, 2 masks
R 172.16.0.0/16 [120/1] via 10.1.5.2, 00:00:14, FastEthernet0/0
D 172.16.10.0/24 [90/28160] via 10.1.5.2, 00:07:23, FastEthernet0/0
D 192.168.10.0/24 [90/2172416] via 10.1.3.2, 00:09:13, Serial0/0/1
[90/2172416] via 10.1.2.2, 00:09:13, Serial0/0/0
D 192.168.20.0/24 [90/2172416] via 10.1.3.2, 00:09:13, Serial0/0/1
[90/2172416] via 10.1.2.2, 00:09:13, Serial0/0/0
D 192.168.30.0/24 [90/2172416] via 10.1.4.2, 00:08:59, Serial0/1/0
D 192.168.40.0/24 [90/2172416] via 10.1.4.2, 00:08:59, Serial0/1/0
Shows the entire routing table
Corp#
show ip
eigrp toplogy
all nets the Corp router can see, including on the other side of other routers
IP-EIGRP Topology Table for AS 10/ID(10.1.5.1)
Codes: P - Passive, A - Active, U - Update, Q - Query, R - Reply,
r - Reply status
directly connected via local egress interface
P 10.1.1.0/24, 1 successors, FD is 25625600
via Connected, Vlan1
P 10.1.2.0/24, 1 successors, FD is 2169856
via Connected, Serial0/0/0
P 10.1.3.0/24, 1 successors, FD is 2169856
via Connected, Serial0/0/1
P 10.1.4.0/24, 1 successors, FD is 2169856
via Connected, Serial0/1/0
P 10.1.5.0/24, 1 successors, FD is 28160
via Connected, FastEthernet0/0
remotely connected via remote ingress ip address
P 172.16.10.0/24, 1 successors, FD is 28160
via 10.1.5.2 (28160/25600), FastEthernet0/0
P 192.168.10.0/24, 2 successors, FD is 2172416
via 10.1.3.2 (2172416/28160), Serial0/0/1
via 10.1.2.2 (2172416/28160), Serial0/0/0
P 192.168.20.0/24, 2 successors, FD is 2172416
via 10.1.3.2 (2172416/28160), Serial0/0/1
via 10.1.2.2 (2172416/28160), Serial0/0/0
P 192.168.30.0/24, 1 successors, FD is 2172416
via 10.1.4.2 (2172416/28160), Serial0/1/0
P 192.168.40.0/24, 1 successors, FD is 2172416
via 10.1.4.2 (2172416/28160), Serial0/1/0
Corp#
show ip
eigrp interfaces
local interfaces on Corp, with peer data, 5 total, including VLAN1 (0 peers, no router on this network)
IP-EIGRP interfaces for process 10
Xmit Queue Mean Pacing Time Multicast Pending
Interface Peers Un/Reliable SRTT Un/Reliable Flow Timer Routes
Vlan 0 0/0 1236 0/10 0 0
Fa0/0 1 0/0 1236 0/10 0 0
Se0/0/1 1 0/0 1236 0/10 0 0
Se0/1/0 1 0/0 1236 0/10 0 0
Se0/0/0 1 0/0 1236 0/10 0 0
Corp#
show ip
eigrp neighbors
remote interfaces on the 4 neighboring routers
IP-EIGRP neighbors for process 10
H Address Interface Hold Uptime SRTT RTO Q Seq
(sec) (ms) Cnt Num
0 10.1.2.2 Se0/0/0 14 00:54:33 40 1000 0 58
1 10.1.3.2 Se0/0/1 10 00:54:33 40 1000 0 57
2 10.1.4.2 Se0/1/0 14 00:53:38 40 1000 0 51
3 10.1.5.2 Fa0/0 11 00:52:49 40 1000 0 33
4. Compare OSPF and RIPv1
RIPv1 is distance-vector and supports only classful routing. No VLSM
OSPF is link-state and supports VLSM and classless routing
5. Know how OSPF routers become neighboars and/or adjacent
they become neighbors when they see eachother's hello packets.
area id must match, links must be on the same subnet, hello/dead timers must be the same.
OSPF only shares routes with neigbors who have also established adjacencies. NOT ALL NEIGHBORS become adjacent.
When an OSPF router first receives a hello packet, it verifies that the data in some fields matches its own locally configured information.
Should any of the checked data be different, the hello packet is discarded and not processed. The data fields verified are the Area ID,
Authentication, Network Mask (on broadcast networks), Hello Interval, Router Dead Interval, and Options fields. If this information doesn’t match,
then neighborship is stuck in the down stage.
packetpushers.net
6. Be able to configure single-area OSPF
two commands:
router ospf [process id]
network x.x.x.x y.y.y.y area z
7. Be able to verify the operation of OSPF
Corp#
show ip
protocols
Corp#
show ip
route
Corp#
show ip
ospf
Corp#
show ip
ospf database
Corp#
show ip
ospf interface
Corp#
show ip
ospf neighbor
IOS 15.1
Corp#
show ip
protocols
Routing Protocol is "ospf 132"
Outgoing update filter list for all interfaces is not set
Incoming update filter list for all interfaces is not set
Router ID 10.1.5.1
Number of areas in this router is 1. 1 normal 0 stub 0 nssa
Maximum path: 4
Routing for Networks:
10.1.0.0 0.0.255.255 area 0
Routing Information Sources:
Gateway Distance Last Update
10.1.5.1 110 00:08:51
172.16.10.1 110 00:08:51
192.168.20.1 110 00:12:53
192.168.40.1 110 00:09:35
Distance: (default is 110)
IOS 15.1
Corp#
show ip
route
10.0.0.0/8 is variably subnetted, 10 subnets, 2 masks
C 10.1.1.0/24 is directly connected, Vlan1
L 10.1.1.1/32 is directly connected, Vlan1
C 10.1.2.0/24 is directly connected, Serial0/0/0
L 10.1.2.1/32 is directly connected, Serial0/0/0
C 10.1.3.0/24 is directly connected, Serial0/0/1
L 10.1.3.1/32 is directly connected, Serial0/0/1
C 10.1.4.0/24 is directly connected, Serial0/1/0
L 10.1.4.1/32 is directly connected, Serial0/1/0
C 10.1.5.0/24 is directly connected, FastEthernet0/0
L 10.1.5.1/32 is directly connected, FastEthernet0/0
172.16.0.0/24 is subnetted, 1 subnets
O 172.16.10.0/24 [110/10] via 10.1.5.2, 00:09:09, FastEthernet0/0
O 192.168.10.0/24 [110/65] via 10.1.2.2, 00:13:11, Serial0/0/0
O 192.168.20.0/24 [110/65] via 10.1.2.2, 00:13:01, Serial0/0/0
O 192.168.30.0/24 [110/65] via 10.1.4.2, 00:09:54, Serial0/1/0
O 192.168.40.0/24 [110/65] via 10.1.4.2, 00:09:54, Serial0/1/0
IOS 15.1
Corp#
show ip
ospf
Routing Process "ospf 132" with ID 10.1.5.1
Supports only single TOS(TOS0) routes
Supports opaque LSA
SPF schedule delay 5 secs, Hold time between two SPFs 10 secs
Minimum LSA interval 5 secs. Minimum LSA arrival 1 secs
Number of external LSA 0. Checksum Sum 0x000000
Number of opaque AS LSA 0. Checksum Sum 0x000000
Number of DCbitless external and opaque AS LSA 0
Number of DoNotAge external and opaque AS LSA 0
Number of areas in this router is 1. 1 normal 0 stub 0 nssa
External flood list length 0
Area BACKBONE(0)
Number of interfaces in this area is 5
Area has no authentication
SPF algorithm executed 7 times
Area ranges are
Number of LSA 5. Checksum Sum 0x034486
Number of opaque link LSA 0. Checksum Sum 0x000000
Number of DCbitless LSA 0
Number of indication LSA 0
Number of DoNotAge LSA 0
Flood list length 0
IOS 15.1
Corp#
show ip
ospf database
OSPF Router with ID (10.1.5.1) (Process ID 132)
Router Link States (Area 0)
Link ID ADV Router Age Seq# Checksum Link count
192.168.20.1 192.168.20.1 854 0x80000006 0x00ae08 6
192.168.40.1 192.168.40.1 656 0x80000004 0x006bc6 4
10.1.5.1 10.1.5.1 612 0x8000000f 0x00ab77 8
172.16.10.1 172.16.10.1 612 0x80000003 0x00b30d 2
Net Link States (Area 0)
Link ID ADV Router Age Seq# Checksum
10.1.5.1 10.1.5.1 612 0x80000001 0x00cc34
ADV Router aka RID/Router ID, the highest IP address on the router
we are seeing three connected routers + our own router (Corp at 10.1.5.1)
IOS 15.1
Corp#
show ip
ospf interface
Vlan1 is up, line protocol is up
Internet address is 10.1.1.1/24, Area 0
Process ID 132, Router ID 10.1.5.1, Network Type BROADCAST, Cost: 1
Transmit Delay is 1 sec, State DR, Priority 1
Designated Router (ID) 10.1.5.1, Interface address 10.1.1.1
No backup designated router on this network
Timer intervals configured, Hello 10, Dead 40, Wait 40, Retransmit 5
Hello due in 00:00:08
Index 1/1, flood queue length 0
Next 0x0(0)/0x0(0)
Last flood scan length is 1, maximum is 1
Last flood scan time is 0 msec, maximum is 0 msec
Neighbor Count is 0, Adjacent neighbor count is 0
Suppress hello for 0 neighbor(s)
FastEthernet0/0 is up, line protocol is up
Internet address is 10.1.5.1/24, Area 0
Process ID 132, Router ID 10.1.5.1, Network Type BROADCAST, Cost: 1
Transmit Delay is 1 sec, State DR, Priority 1
Designated Router (ID) 10.1.5.1, Interface address 10.1.5.1
Backup Designated Router (ID) 172.16.10.1, Interface address 10.1.5.2
Timer intervals configured, Hello 10, Dead 40, Wait 40, Retransmit 5
Hello due in 00:00:07
Index 2/2, flood queue length 0
Next 0x0(0)/0x0(0)
Last flood scan length is 1, maximum is 1
Last flood scan time is 0 msec, maximum is 0 msec
Neighbor Count is 1, Adjacent neighbor count is 1
Adjacent with neighbor 172.16.10.1 (Backup Designated Router)
Suppress hello for 0 neighbor(s)
Serial0/0/1 is up, line protocol is up
Internet address is 10.1.3.1/24, Area 0
Process ID 132, Router ID 10.1.5.1, Network Type POINT-TO-POINT, Cost: 64
Transmit Delay is 1 sec, State POINT-TO-POINT,
Timer intervals configured, Hello 10, Dead 40, Wait 40, Retransmit 5
Hello due in 00:00:07
Index 3/3, flood queue length 0
Next 0x0(0)/0x0(0)
Last flood scan length is 1, maximum is 1
Last flood scan time is 0 msec, maximum is 0 msec
Neighbor Count is 1 , Adjacent neighbor count is 1
Adjacent with neighbor 192.168.20.1
Suppress hello for 0 neighbor(s)
Serial0/1/0 is up, line protocol is up
Internet address is 10.1.4.1/24, Area 0
Process ID 132, Router ID 10.1.5.1, Network Type POINT-TO-POINT, Cost: 64
Transmit Delay is 1 sec, State POINT-TO-POINT,
Timer intervals configured, Hello 10, Dead 40, Wait 40, Retransmit 5
Hello due in 00:00:07
Index 4/4, flood queue length 0
Next 0x0(0)/0x0(0)
Last flood scan length is 1, maximum is 1
Last flood scan time is 0 msec, maximum is 0 msec
Neighbor Count is 1 , Adjacent neighbor count is 1
Adjacent with neighbor 192.168.40.1
Suppress hello for 0 neighbor(s)
Serial0/0/0 is up, line protocol is up
Internet address is 10.1.2.1/24, Area 0
Process ID 132, Router ID 10.1.5.1, Network Type POINT-TO-POINT, Cost: 64
Transmit Delay is 1 sec, State POINT-TO-POINT,
Timer intervals configured, Hello 10, Dead 40, Wait 40, Retransmit 5
Hello due in 00:00:07
Index 5/5, flood queue length 0
Next 0x0(0)/0x0(0)
Last flood scan length is 1, maximum is 1
Last flood scan time is 0 msec, maximum is 0 msec
Neighbor Count is 1 , Adjacent neighbor count is 1
Adjacent with neighbor 192.168.20.1
Suppress hello for 0 neighbor(s)
IOS 15.1
Corp#
show ip
ospf neighbor
Neighbor ID Pri State Dead Time Address Interface
192.168.20.1 0 FULL/ - 00:00:31 10.1.3.2 Serial0/0/1
192.168.40.1 0 FULL/ - 00:00:33 10.1.4.2 Serial0/1/0
192.168.20.1 0 FULL/ - 00:00:31 10.1.2.2 Serial0/0/0
172.16.10.1 1 FULL/BDR 00:00:32 10.1.5.2 FastEthernet0/0
Flashcards
Chapter 9 Written Lab 9.0
1. What four routed protocols are supported by EIGRP?
IPX, IPv4, IPv6, AppleTalk
2. When is redistribution required for EIGRP?
when there are multiple autonomous systems
redistribution is required when more than one EIGRP session or process is running and they are identified with different ASNs.
redistribution shares toplogy information between EIGRP sessions
3. What command would be used to enable EIGRP with an autonmous system number of 300?
router eigrp 300
4. What command will tell EIGRP that it is connected to network 172.10.0.0?
network 172.10.0.0
5. What type of EIGRP interface will neither send nor receive Hello packets?
passive-interface s0/0
6. Write the command that will enable OSPF process 101 on a router
router ospf 101
7. Write the command that will display details of all OSFP routing processes enabled on a router
show ip ospf
8. Write the command that will display interface-specific OSPF information
show ip ospf interface
9. Write the command that will display all OSPF neighbors
show ip ospf neighbor
10. Write the command that will display all different OSPF route types that are currently known by the router
show ip route ospf
Chapter 9 Hands-On Labs
Build the network and configure interfaces
LabA(config)#
int f0/0
LabA(config-if)#
ip addr 172.16.10.1 255.255.255.0
LabA(config-if)#
no shut
LabB(config)#
int f0/0
LabB(config-if)#
ip addr 172.16.10.2 255.255.255.0
LabB(config-if)#
no shut
LabB(config-if)#
int s0/0/0
LabB(config-if)#
ip addr 172.16.20.1 255.255.255.0
LabB(config-if)#
no shut
LabC(config)#
int f0/0
LabC(config-if)#
ip addr 172.16.30.1 255.255.255.0
LabC(config-if)#
no shut
LabC(config-if)#
int s0/0/0
LabC(config-if)#
ip addr 172.16.20.2 255.255.255.0
LabC(config-if)#
no shut
LabC(config-if)#
int s0/0/1
LabC(config-if)#
ip addr 172.16.40.1 255.255.255.0
LabC(config-if)#
no shut
LabD(config)#
int s0/0/0
LabD(config-if)#
ip addr 172.16.40.2 255.255.255.0
LabD(config-if)#
no shut
LabD(config-if)#
int f0/0
LabD(config-if)#
ip addr 172.16.50.1 255.255.255.0
LabD(config-if)#
no shut
9.1 - Configure and Verfiy EIGRP
configure EIGRP on all 4 routers and observe results
LabA
LabA(config)#
router eigrp 100
LabA(config-router)#
net 172.16.0.0
[no output]
LabA#
show ip eigrp neighbors
IP-EIGRP neighbors for process 100
LabA#
show ip eigrp topology
IP-EIGRP Topology Table for AS 100/ID(172.16.10.1)
Codes: P - Passive, A - Active, U - Update, Q - Query, R - Reply,
r - Reply status
P 172.16.10.0/24, 1 successors, FD is 28160
via Connected, FastEthernet0/0
LabA#
show ip eigrp interfaces
IP-EIGRP interfaces for process 100
Xmit Queue Mean Pacing Time Multicast Pending
Interface Peers Un/Reliable SRTT Un/Reliable Flow Timer Routes
Fa0/0 0 0/0 1236 0/10 0 0
no neighbors at this point since EIGRP is only active on this router. One successor AKA route, which is the connection out of this router.
But note that we have no information about what's on the other side of that link
LabB
LabB(config)#
router eigrp 100
LabB(config-router)#
net 172.16.0.0
%DUAL-5-NBRCHANGE: IP-EIGRP 100:
Neighbor 172.16.10.1 (FastEthernet0/0) is up: new adjacency
LabB#
show ip eigrp neighbors
IP-EIGRP neighbors for process 100
H Address Interface Hold Uptime SRTT RTO Q Seq
(sec) (ms) Cnt Num
0 172.16.10.1 Fa0/0 12 00:00:14 40 1000 0 1
LabB#
show ip eigrp topology
IP-EIGRP Topology Table for AS 100/ID(172.16.20.1)
Codes: P - Passive, A - Active, U - Update, Q - Query, R - Reply,
r - Reply status
P 172.16.10.0/24, 1 successors, FD is 28160
via Connected, FastEthernet0/0
P 172.16.20.0/24, 1 successors, FD is 2169856
via Connected, Serial0/0/0
LabB#
show ip eigrp interfaces
IP-EIGRP interfaces for process 100
Xmit Queue Mean Pacing Time Multicast Pending
Interface Peers Un/Reliable SRTT Un/Reliable Flow Timer Routes
Fa0/0 1 0/0 1236 0/10 0 0
Se0/0/0 0 0/0 1236 0/10 0 0
We can see a neighbor at .1
We now have two paths out of this router. Left to neighbor. Exit at right is available as successor(route), but again we have no info about
what is on the other side, since that router has no EIGRP yet (s0/0/0 has no peers, but is an EIGRP interface)
LabC
LabC(config)#
router eigrp 100
LabC(config-router)#
net 172.16.0.0
%DUAL-5-NBRCHANGE: IP-EIGRP 100:
Neighbor 172.16.20.1 (Serial0/0/0) is up: new adjacency
LabC#
show ip eigrp neighbors
IP-EIGRP neighbors for process 100
H Address Interface Hold Uptime SRTT RTO Q Seq
(sec) (ms) Cnt Num
0 172.16.20.1 Se0/0/0 12 00:00:25 40 1000 0 8
LabC#
show ip eigrp toplogy
IP-EIGRP Topology Table for AS 100/ID(172.16.40.1)
Codes: P - Passive, A - Active, U - Update, Q - Query, R - Reply,
r - Reply status
P 172.16.10.0/24, 1 successors, FD is 2172416
via 172.16.20.1 (2172416/28160), Serial0/0/0
P 172.16.20.0/24, 1 successors, FD is 2169856
via Connected, Serial0/0/0
P 172.16.30.0/24, 1 successors, FD is 28160
via Connected, FastEthernet0/0
P 172.16.40.0/24, 1 successors, FD is 2169856
via Connected, Serial0/0/1
LabC#
show ip eigrp interfaces
IP-EIGRP interfaces for process 100
Xmit Queue Mean Pacing Time Multicast Pending
Interface Peers Un/Reliable SRTT Un/Reliable Flow Timer Routes
Fa0/0 0 0/0 1236 0/10 0 0
Se0/0/0 1 0/0 1236 0/10 0 0
Se0/0/1 0 0/0 1236 0/10 0 0
.1 router B interface is now a neighbor.
LabC topology shows the 3 direct connected networks AND the network on the other side of LabB since LabB is our EIGRP neighbor
3 eigrp interfaces:
Fa0/0 is ours at LabC- no peers bc there is no eigrp router on the other end
s0/0/0 is our interface out left to LabB which is an EIGRP peer
s0/0/1 is our interface out right which does not see an EIGRP peer but does put that net 172.16.40.0 in our topology
LabD
LabD(config)#
router eigrp 100
LabD(config-router)#
net 172.16.0.0
%DUAL-5-NBRCHANGE: IP-EIGRP 100:
Neighbor 172.16.40.1 (Serial0/0/0) is up: new adjacency
LabD#
show ip eigrp neighbors
IP-EIGRP neighbors for process 100
H Address Interface Hold Uptime SRTT RTO Q Seq
(sec) (ms) Cnt Num
0 172.16.40.1 Se0/0/0 11 00:00:14 40 1000 0 6
LabD#
show ip eigrp topology
IP-EIGRP Topology Table for AS 100/ID(172.16.50.1)
Codes: P - Passive, A - Active, U - Update, Q - Query, R - Reply,
r - Reply status
P 172.16.10.0/24, 1 successors, FD is 2684416
via 172.16.40.1 (2684416/2172416), Serial0/0/0
P 172.16.20.0/24, 1 successors, FD is 2681856
via 172.16.40.1 (2681856/2169856), Serial0/0/0
P 172.16.30.0/24, 1 successors, FD is 2172416
via 172.16.40.1 (2172416/28160), Serial0/0/0
P 172.16.40.0/24, 1 successors, FD is 2169856
via Connected, Serial0/0/0
P 172.16.50.0/24, 1 successors, FD is 28160
via Connected, FastEthernet0/0
LabD#
show ip eigrp interfaces
IP-EIGRP interfaces for process 100
Xmit Queue Mean Pacing Time Multicast Pending
Interface Peers Un/Reliable SRTT Un/Reliable Flow Timer Routes
Fa0/0 0 0/0 1236 0/10 0 0
Se0/0/0 1 0/0 1236 0/10 0 0
LabC to our left is now a neighbor at 172.16.40.1
toplogy shows a route out to the right (no router on that end)
a route to the left to LabC .40.0
the .10.0, .20.0, and .30.0 networks via info from LabC
2 eigrp interfaces-
fa0/0 out to the right
s0/0/0 out left to LabC
Time to remove EIGRP from all four routers to prepare for the OSPF lab next,
since EIGRP has a lower AD than OSPF
LabA(config)#
no router eigrp 100
LabB(config)#
no router eigrp 100
LabC(config)#
no router eigrp 100
LabD(config)#
no router eigrp 100
9.2 - Enabling the OSPF Process
9.3 - Configuring OSPF Interfaces
9.4 - Verifying OSPF Operation
LabA
LabA(config)#
router ospf 100
LabA(config-router)#
net 172.16.10.1 0.0.0.0 area 0
[no output]
LabA#
show ip ospf neighbor
[no output]
LabA#
show ip ospf database
OSPF Router with ID (172.16.10.1) (Process ID 100)
Router Link States (Area 0)
Link ID ADV Router Age Seq# Checksum Link count
172.16.10.1 172.16.10.1 44 0x80000001 0x00b24b 1
LabA#
show ip ospf interface
FastEthernet0/0 is up, line protocol is up
Internet address is 172.16.10.1/24, Area 0
Process ID 100, Router ID 172.16.10.1, Network Type BROADCAST, Cost: 1
Transmit Delay is 1 sec, State DR, Priority 1
Designated Router (ID) 172.16.10.1, Interface address 172.16.10.1
No backup designated router on this network
Timer intervals configured, Hello 10, Dead 40, Wait 40, Retransmit 5
Hello due in 00:00:08
Index 1/1, flood queue length 0
Next 0x0(0)/0x0(0)
Last flood scan length is 1, maximum is 1
Last flood scan time is 0 msec, maximum is 0 msec
Neighbor Count is 0, Adjacent neighbor count is 0
Suppress hello for 0 neighbor(s)
we're including this router's interface 172.16.10.1 in our ospf area 0
fa0/0 now registers as an ospf interface
the ospf database includes data about this link only.... LabA is counting itself(10.1) as ADVERTISTING router?
the designated router is .1 LabA
LabB
LabB(config)#
router ospf 101
LabB(config-router)#
net 172.16.10.2 0.0.0.0 area 0
LabB(config-router)#
net 172.16.20.1 0.0.0.0 area 0
01:26:36: %OSPF-5-ADJCHG: Process 101, Nbr 172.16.10.1
on FastEthernet0/0 from LOADING to FULL, Loading Done
LabB#
show ip ospf neighbor
Neighbor ID Pri State Dead Time Address Interface
172.16.10.1 1 FULL/DR 00:00:33 172.16.10.1
LabB#
show ip ospf database
OSPF Router with ID (172.16.20.1) (Process ID 101)
Router Link States (Area 0)
Link ID ADV Router Age Seq# Checksum Link count
172.16.10.1 172.16.10.1 145 0x80000002 0x0067cd 1
172.16.20.1 172.16.20.1 32 0x80000003 0x006e8f 2
Net Link States (Area 0)
Link ID ADV Router Age Seq# Checksum
172.16.10.1 172.16.10.1 145 0x80000001 0x00953d
LabB#
show ip ospf interface
FastEthernet0/0 is up, line protocol is up
Internet address is 172.16.10.2/24, Area 0
Process ID 101, Router ID 172.16.20.1, Network Type BROADCAST, Cost: 1
Transmit Delay is 1 sec, State BDR, Priority 1
Designated Router (ID) 172.16.10.1, Interface address 172.16.10.1
Backup Designated Router (ID) 172.16.20.1, Interface address 172.16.10.2
Timer intervals configured, Hello 10, Dead 40, Wait 40, Retransmit 5
Hello due in 00:00:03
Index 1/1, flood queue length 0
Next 0x0(0)/0x0(0)
Last flood scan length is 1, maximum is 1
Last flood scan time is 0 msec, maximum is 0 msec
Neighbor Count is 1, Adjacent neighbor count is 1
Adjacent with neighbor 172.16.10.1 (Designated Router)
Suppress hello for 0 neighbor(s)
Serial0/0/0 is up, line protocol is up
Internet address is 172.16.20.1/24, Area 0
Process ID 101, Router ID 172.16.20.1, Network Type POINT-TO-POINT, Cost: 64
Transmit Delay is 1 sec, State POINT-TO-POINT,
Timer intervals configured, Hello 10, Dead 40, Wait 40, Retransmit 5
Hello due in 00:00:04
Index 2/2, flood queue length 0
Next 0x0(0)/0x0(0)
Last flood scan length is 1, maximum is 1
Last flood scan time is 0 msec, maximum is 0 msec
Suppress hello for 0 neighbor(s)
We've include the two interfaces on this router in the OSPF area
and can now see Router A's interface 10.1 to the left as a neighbor in the area
the "OSPF Database" now shows two links 20.1(local) and 10.1(neighbor) as 'router link states'.
"ADV Router" means advertising router for the two links. The link address is used as the advertising router.
database shows "Net Link States" category with one entry- 172.16.10.1 which is the address of neighbor router to our left
we have two local OSPF interfaces- f0/0 and s0/0/0
LabC
LabC(config)#
router ospf 102
LabC(config-router)#
net 172.16.20.2 0.0.0.0 area 0
LabC(config-router)#
net 172.16.30.1 0.0.0.0 area 0
LabC(config-router)#
net 172.16.40.1 0.0.0.0 area 0
01:33:54: %OSPF-5-ADJCHG: Process 102, Nbr 172.16.20.1
on Serial0/0/0 from LOADING to FULL, Loading Done
LabC#
show ip ospf neighbor
Neighbor ID Pri State Dead Time Address Interface
172.16.20.1 0 FULL/ - 00:00:30 172.16.20.1 Serial0/0/0
LabC#
show ip ospf database
OSPF Router with ID (172.16.40.1) (Process ID 102)
Router Link States (Area 0)
Link ID ADV Router Age Seq# Checksum Link count
172.16.10.1 172.16.10.1 542 0x80000002 0x0067cd 1
172.16.20.1 172.16.20.1 90 0x80000004 0x00a551 3
172.16.40.1 172.16.40.1 37 0x80000004 0x00e47c 4
Net Link States (Area 0)
Link ID ADV Router Age Seq# Checksum
172.16.10.1 172.16.10.1 542 0x80000001 0x00953d
LabC#
show ip ospf interface
Serial0/0/0 is up, line protocol is up
Internet address is 172.16.20.2/24, Area 0
Process ID 102, Router ID 172.16.40.1, Network Type POINT-TO-POINT, Cost: 64
Transmit Delay is 1 sec, State POINT-TO-POINT,
Timer intervals configured, Hello 10, Dead 40, Wait 40, Retransmit 5
Hello due in 00:00:01
Index 1/1, flood queue length 0
Next 0x0(0)/0x0(0)
Last flood scan length is 1, maximum is 1
Last flood scan time is 0 msec, maximum is 0 msec
Neighbor Count is 1 , Adjacent neighbor count is 1
Adjacent with neighbor 172.16.20.1
Suppress hello for 0 neighbor(s)
FastEthernet0/0 is up, line protocol is up
Internet address is 172.16.30.1/24, Area 0
Process ID 102, Router ID 172.16.40.1, Network Type BROADCAST, Cost: 1
Transmit Delay is 1 sec, State DR, Priority 1
Designated Router (ID) 172.16.40.1, Interface address 172.16.30.1
No backup designated router on this network
Timer intervals configured, Hello 10, Dead 40, Wait 40, Retransmit 5
Hello due in 00:00:02
Index 2/2, flood queue length 0
Next 0x0(0)/0x0(0)
Last flood scan length is 1, maximum is 1
Last flood scan time is 0 msec, maximum is 0 msec
Neighbor Count is 0, Adjacent neighbor count is 0
Suppress hello for 0 neighbor(s)
Serial0/0/1 is up, line protocol is up
Internet address is 172.16.40.1/24, Area 0
Process ID 102, Router ID 172.16.40.1, Network Type POINT-TO-POINT, Cost: 64
Transmit Delay is 1 sec, State POINT-TO-POINT,
Timer intervals configured, Hello 10, Dead 40, Wait 40, Retransmit 5
Hello due in 00:00:08
Index 3/3, flood queue length 0
Next 0x0(0)/0x0(0)
Last flood scan length is 1, maximum is 1
Last flood scan time is 0 msec, maximum is 0 msec
Suppress hello for 0 neighbor(s)
we include the three nets conneted to labC in the area.. 20.0, 30.0, and 40.0
link to our left, 20.1 is visible as "Neighbor"
OSPF Database-
Router Link States are
10.1(Router A)
20.1(Router B)
40.1(Router C)(This router)
Net Link States
10.1(Router A)... why does only Router A show here?
Reference- router link state vs net link state
Router Link States are type 1 LSAs. It lists all the routers in the area and the number of interfaces. 40.1 has 4 interfaces
Net Link States are the multi-access networks (Type 2 LSAs). The ADV (advertising router) is the DR.
LabD
LabD(config)#
router ospf 103
LabD(config-router)#
net 172.16.40.2 0.0.0.0 area 0
LabD(config-router)#
net 172.16.50.1 0.0.0.0 area 0
01:37:11: %OSPF-5-ADJCHG: Process 103, Nbr 172.16.40.1
on Serial0/0/0 from LOADING to FULL, Loading Done
LabD#
show ip ospf neighbor
Neighbor ID Pri State Dead Time Address Interface
172.16.40.1 0 FULL/ - 00:00:32 172.16.40.1 Serial0/0/0
LabD#
show ip ospf database
OSPF Router with ID (172.16.50.1) (Process ID 103)
Router Link States (Area 0)
Link ID ADV Router Age Seq# Checksum Link count
172.16.10.1 172.16.10.1 785 0x80000002 0x0067cd 1
172.16.20.1 172.16.20.1 333 0x80000004 0x00a551 3
172.16.40.1 172.16.40.1 111 0x80000005 0x00013b 5
172.16.50.1 172.16.50.1 53 0x80000003 0x001023 3
Net Link States (Area 0)
Link ID ADV Router Age Seq# Checksum
172.16.10.1 172.16.10.1 785 0x80000001 0x00953d
LabD#
show ip ospf interface
Serial0/0/0 is up, line protocol is up
Internet address is 172.16.40.2/24, Area 0
Process ID 103, Router ID 172.16.50.1, Network Type POINT-TO-POINT, Cost: 64
Transmit Delay is 1 sec, State POINT-TO-POINT,
Timer intervals configured, Hello 10, Dead 40, Wait 40, Retransmit 5
Hello due in 00:00:01
Index 1/1, flood queue length 0
Next 0x0(0)/0x0(0)
Last flood scan length is 1, maximum is 1
Last flood scan time is 0 msec, maximum is 0 msec
Neighbor Count is 1 , Adjacent neighbor count is 1
Adjacent with neighbor 172.16.40.1
Suppress hello for 0 neighbor(s)
FastEthernet0/0 is up, line protocol is up
Internet address is 172.16.50.1/24, Area 0
Process ID 103, Router ID 172.16.50.1, Network Type BROADCAST, Cost: 1
Transmit Delay is 1 sec, State WAITING, Priority 1
No designated router on this network
No backup designated router on this network
Timer intervals configured, Hello 10, Dead 40, Wait 40, Retransmit 5
Hello due in 00:00:04
Index 2/2, flood queue length 0
Next 0x0(0)/0x0(0)
Last flood scan length is 1, maximum is 1
Last flood scan time is 0 msec, maximum is 0 msec
Neighbor Count is 0, Adjacent neighbor count is 0
Suppress hello for 0 neighbor(s)
observations
the OSPF databases now match across all 4 routers.
NOTE that this is a database of routers, identified by
router ID. It is not a topology that lists routers AND routes,
like in the "equivalent" eigrp command.show eigrp topology
----------------------------------------------------------------------------------
PAUSE- a tale of a misconfigured network
After a 9 month hiatus, I am reviewing this book and have made it back to Chapter 9. I'm studing this webpage, working thorough the OSPF configurations
described above, and I get stuck on the concept of "link count" under "Router Link States" found in the output of show ip ospf database
The structure of the notes above is helpful, because I was tracking the state of each router BEFORE i made changes to the subsquent router. But just to be sure,
today I decided to recreate the topology, then configure each router one at a time, noting the results as I went.
And I ran into some problems.
Here is the original topology:
And today's recreated toplogy:
After replicating the toplogy and programming the IP addresses on each router, I started on configurations, just like before:
LabA
LabA(config)#
router ospf 100
LabA(config-router)#
net 172.16.10.1 0.0.0.0 area 0
[no output]
LabA#
show ip ospf neighbor
[no output]
LabA#
show ip ospf database
OSPF Router with ID (172.16.10.1) (Process ID 100)
Router Link States (Area 0)
Link ID ADV Router Age Seq# Checksum Link count
172.16.10.1 172.16.10.1 44 0x80000001 0x00b24b 1
LabA#
show ip ospf interface
FastEthernet0/0 is up, line protocol is up
Internet address is 172.16.10.1/24, Area 0
Process ID 100, Router ID 172.16.10.1, Network Type BROADCAST, Cost: 1
Transmit Delay is 1 sec, State DR, Priority 1
Designated Router (ID) 172.16.10.1, Interface address 172.16.10.1
No backup designated router on this network
Timer intervals configured, Hello 10, Dead 40, Wait 40, Retransmit 5
Hello due in 00:00:08
Index 1/1, flood queue length 0
Next 0x0(0)/0x0(0)
Last flood scan length is 1, maximum is 1
Last flood scan time is 0 msec, maximum is 0 msec
Neighbor Count is 0, Adjacent neighbor count is 0
Suppress hello for 0 neighbor(s)
good so far.... On to LabB router
LabB
LabB(config)#
router ospf 101
LabB(config-router)#
net 172.16.10.2 0.0.0.0 area 0
LabB(config-router)#
net 172.16.20.1 0.0.0.0 area 0
01:26:36: %OSPF-5-ADJCHG: Process 101, Nbr 172.16.10.1
on FastEthernet0/0 from LOADING to FULL, Loading Done
LabB#
show ip ospf neighbor
Neighbor ID Pri State Dead Time Address Interface
172.16.10.1 1 FULL/DR 00:00:33 172.16.10.1
LabB#
show ip ospf database
OSPF Router with ID (172.16.20.1) (Process ID 101)
Router Link States (Area 0)
Link ID ADV Router Age Seq# Checksum Link count
172.16.10.1 172.16.10.1 145 0x80000002 0x0067cd 1
172.16.20.1 172.16.20.1 32 0x80000003 0x006e8f 2
Net Link States (Area 0)
Link ID ADV Router Age Seq# Checksum
172.16.10.1 172.16.10.1 145 0x80000001 0x00953d
LabB#
show ip ospf interface
FastEthernet0/0 is up, line protocol is up
Internet address is 172.16.10.2/24, Area 0
Process ID 101, Router ID 172.16.20.1, Network Type BROADCAST, Cost: 1
Transmit Delay is 1 sec, State BDR, Priority 1
Designated Router (ID) 172.16.10.1, Interface address 172.16.10.1
Backup Designated Router (ID) 172.16.20.1, Interface address 172.16.10.2
Timer intervals configured, Hello 10, Dead 40, Wait 40, Retransmit 5
Hello due in 00:00:03
Index 1/1, flood queue length 0
Next 0x0(0)/0x0(0)
Last flood scan length is 1, maximum is 1
Last flood scan time is 0 msec, maximum is 0 msec
Neighbor Count is 1, Adjacent neighbor count is 1
Adjacent with neighbor 172.16.10.1 (Designated Router)
Suppress hello for 0 neighbor(s)
Serial0/0/0 is up, line protocol is up
Internet address is 172.16.20.1/24, Area 0
Process ID 101, Router ID 172.16.20.1, Network Type POINT-TO-POINT, Cost: 64
Transmit Delay is 1 sec, State POINT-TO-POINT,
Timer intervals configured, Hello 10, Dead 40, Wait 40, Retransmit 5
Hello due in 00:00:04
Index 2/2, flood queue length 0
Next 0x0(0)/0x0(0)
Last flood scan length is 1, maximum is 1
Last flood scan time is 0 msec, maximum is 0 msec
Suppress hello for 0 neighbor(s)
still looks good; same as before.... On to LabC router
LabC
LabC(config)#
router ospf 102
LabC(config-router)#
net 172.16.20.2 0.0.0.0 area 0
LabC(config-router)#
net 172.16.30.1 0.0.0.0 area 0
LabC(config-router)#
net 172.16.40.1 0.0.0.0 area 0
01:33:54: %OSPF-5-ADJCHG: Process 102, Nbr 172.16.20.1
on Serial0/0/0 from LOADING to FULL, Loading Done
LabC#
show ip ospf neighbor
[no output]
And here is where I ran into trouble. The show ip ospf neighbor command returns nothing. How can
that be?
After awhile I realized it is due to a misconfiguration in the topology.
For Lab C, I programmed the interfaces as follows:
LabC(config)#
int f0/0
LabC(config-if)#
ip addr 172.16.30.1 255.255.255.0
LabC(config-if)#
no shut
LabC(config-if)#
int s0/0/0
LabC(config-if)#
ip addr 172.16.20.2 255.255.255.0
LabC(config-if)#
no shut
LabC(config-if)#
int s0/0/1
LabC(config-if)#
ip addr 172.16.40.1 255.255.255.0
LabC(config-if)#
no shut
and again here is the topology for that router:
but here is what it SHOULD HAVE looked like (as it did the first time I built it)
S0/0/0 and S0/0/1 are swapped. When I gave the IP 172.16.20.2 to s/0/0/0, thinking that was the interface on the left side
which faces Lab B, I was actually giving 172.16.20.2 to the right side, facing LabC (which has no OSPF configs yet.)
Since the left side got got the IP intended for the right side which was 172.16.40.1
the inverse also occured-
the right side got the IP intended for the left which was 172.16.20.2
LabC left side should have been
s0/0/0 with 20.2
and LabC right side should have been
s0/0/1 with 40.1
The correct IPs were mapped to the correct interfaces. But the mistake happened before I even programmed them.
When I made the connections from LabB to LabC and from LabD to LabC, I plugged then into the wrong ports.
Interestingly.. not only is this causing OSPF to not see B as a neighbor from C.. but B and C cannot ping eachother either.
@B the config is 172.16.20.1/24 @ S0/0/0
@C the config is 172.16.40.1/24 @ S/0/0/1
meaning they are not even on the same network! But the system is not throwing any errors or bringing it to my attention.
It just fails to connect.
To correct the issue, I simply deleted those two links and re-created them. Worth noting, I used the auto select cable here,
which does not ask which interface you want to use when attaching. Earlier I must have plugged the right side first, and
auto select plugged into 0/0/0.
This time I plugged into left side first.
Now LabC OSPF data is reading out correctly...
LabC
LabC(config)#
router ospf 102
LabC(config-router)#
net 172.16.20.2 0.0.0.0 area 0
LabC(config-router)#
net 172.16.30.1 0.0.0.0 area 0
LabC(config-router)#
net 172.16.40.1 0.0.0.0 area 0
01:33:54: %OSPF-5-ADJCHG: Process 102, Nbr 172.16.20.1
on Serial0/0/0 from LOADING to FULL, Loading Done
LabC#
show ip ospf neighbor
Neighbor ID Pri State Dead Time Address Interface
172.16.20.1 0 FULL/ - 00:00:30 172.16.20.1 Serial0/0/0
LabC#
show ip ospf database
OSPF Router with ID (172.16.40.1) (Process ID 102)
Router Link States (Area 0)
Link ID ADV Router Age Seq# Checksum Link count
172.16.10.1 172.16.10.1 542 0x80000002 0x0067cd 1
172.16.20.1 172.16.20.1 90 0x80000004 0x00a551 3
172.16.40.1 172.16.40.1 37 0x80000004 0x00e47c 4
Net Link States (Area 0)
Link ID ADV Router Age Seq# Checksum
172.16.10.1 172.16.10.1 542 0x80000001 0x00953d
LabC#
show ip ospf interface
Serial0/0/0 is up, line protocol is up
Internet address is 172.16.20.2/24, Area 0
Process ID 102, Router ID 172.16.40.1, Network Type POINT-TO-POINT, Cost: 64
Transmit Delay is 1 sec, State POINT-TO-POINT,
Timer intervals configured, Hello 10, Dead 40, Wait 40, Retransmit 5
Hello due in 00:00:01
Index 1/1, flood queue length 0
Next 0x0(0)/0x0(0)
Last flood scan length is 1, maximum is 1
Last flood scan time is 0 msec, maximum is 0 msec
Neighbor Count is 1 , Adjacent neighbor count is 1
Adjacent with neighbor 172.16.20.1
Suppress hello for 0 neighbor(s)
FastEthernet0/0 is up, line protocol is up
Internet address is 172.16.30.1/24, Area 0
Process ID 102, Router ID 172.16.40.1, Network Type BROADCAST, Cost: 1
Transmit Delay is 1 sec, State DR, Priority 1
Designated Router (ID) 172.16.40.1, Interface address 172.16.30.1
No backup designated router on this network
Timer intervals configured, Hello 10, Dead 40, Wait 40, Retransmit 5
Hello due in 00:00:02
Index 2/2, flood queue length 0
Next 0x0(0)/0x0(0)
Last flood scan length is 1, maximum is 1
Last flood scan time is 0 msec, maximum is 0 msec
Neighbor Count is 0, Adjacent neighbor count is 0
Suppress hello for 0 neighbor(s)
Serial0/0/1 is up, line protocol is up
Internet address is 172.16.40.1/24, Area 0
Process ID 102, Router ID 172.16.40.1, Network Type POINT-TO-POINT, Cost: 64
Transmit Delay is 1 sec, State POINT-TO-POINT,
Timer intervals configured, Hello 10, Dead 40, Wait 40, Retransmit 5
Hello due in 00:00:08
Index 3/3, flood queue length 0
Next 0x0(0)/0x0(0)
Last flood scan length is 1, maximum is 1
Last flood scan time is 0 msec, maximum is 0 msec
Suppress hello for 0 neighbor(s)
Which brings me to the original reason I re-created this topology... I was confused about the LINK COUNTS
here:
OSPF Router with ID (172.16.40.1) (Process ID 102)
Router Link States (Area 0)
Link ID ADV Router Age Seq# Checksum Link count
172.16.10.1 172.16.10.1 542 0x80000002 0x0067cd 1
172.16.20.1 172.16.20.1 90 0x80000004 0x00a551 3
172.16.40.1 172.16.40.1 37 0x80000004 0x00e47c 4
Net Link States (Area 0)
Link ID ADV Router Age Seq# Checksum
172.16.10.1 172.16.10.1 542 0x80000001 0x00953d
The steps of recreating the lab were helpful, but this link answered the question:
Here is the output of each router's command show ip ospf interface as they are
set up one at a time.
LabA - No OSPF at B, C, or D yet
show ip ospf database
OSPF Router with ID (172.16.10.1) (Process ID 100)
Router Link States (Area 0)
Link ID ADV Router Age Seq# Checksum Link count
172.16.10.1 172.16.10.1 44 0x80000001 0x00b24b 1
LabB - No OSPF at C or D yet
show ip ospf database
OSPF Router with ID (172.16.20.1) (Process ID 101)
Router Link States (Area 0)
Link ID ADV Router Age Seq# Checksum Link count
172.16.10.1 172.16.10.1 145 0x80000002 0x0067cd 1
172.16.20.1 172.16.20.1 32 0x80000003 0x006e8f 2
Net Link States (Area 0)
Link ID ADV Router Age Seq# Checksum
172.16.10.1 172.16.10.1 145 0x80000001 0x00953d
the 20.2 interface on this router has 2 ospf links.
The left-facing out to RA, a crossover cable
The right-facing out to RC, a serial cable.
If the solution I found is correct, why is this serial link not being counted twice? The solution (I think)
is revealed after the configuration of the next router...
LabC - No OSPF at D yet
show ip ospf database
OSPF Router with ID (172.16.40.1) (Process ID 102)
Router Link States (Area 0)
Link ID ADV Router Age Seq# Checksum Link count
172.16.10.1 172.16.10.1 542 0x80000002 0x0067cd 1
172.16.20.1 172.16.20.1 90 0x80000004 0x00a551 3
172.16.40.1 172.16.40.1 37 0x80000004 0x00e47c 4
Net Link States (Area 0)
Link ID ADV Router Age Seq# Checksum
172.16.10.1 172.16.10.1 542 0x80000001 0x00953d
NOW we can see that the 20.1 link, which is the right-facing interface on LabB.. aka the router ID..
has THREE OSPF links.
Nothing changed on the left side of B. But on the right side, we now have an active OSPF router at the
other end of the link. This leads me to believe that the forum post was correct that 'serial links are counted twice',
but, more specifically, BOTH ENDS of the serial(PPP) link are counted... IF there is an OSPF router on each end.
This is backed up by the fact that LabC, OSPF id 40.1, has four OSPF links. The top-facing link to the 30
network DOES count.. even though it has no OSPF router on the other end. It counts because it's not a serial link.
The requirement of having an OSPF router on the other end for an interface to count here, only applies
to serial links. And pertains to BOTH ends of the link being counted.
In LabC's case, we have one serial at left, being counted twice. One ethernet at top, being counted once. And
one serial at right only being counted once because LabD is not active with OSPF yet.
If this is correct, then we should see Lab C's 40.1 count go to 5 after LabD is set for OSPF....
LabD - all 4 routers have OSPF
show ip ospf database
OSPF Router with ID (172.16.50.1) (Process ID 103)
Router Link States (Area 0)
Link ID ADV Router Age Seq# Checksum Link count
172.16.10.1 172.16.10.1 785 0x80000002 0x0067cd 1
172.16.20.1 172.16.20.1 333 0x80000004 0x00a551 3
172.16.40.1 172.16.40.1 111 0x80000005 0x00013b 5
172.16.50.1 172.16.50.1 53 0x80000003 0x001023 3
Net Link States (Area 0)
Link ID ADV Router Age Seq# Checksum
172.16.10.1 172.16.10.1 785 0x80000001 0x00953d
and back to LabC.....
show ip ospf database
OSPF Router with ID (172.16.40.1) (Process ID 102)
Router Link States (Area 0)
Link ID ADV Router Age Seq# Checksum Link count
172.16.10.1 172.16.10.1 1174 0x80000002 0x0067cd 1
172.16.20.1 172.16.20.1 722 0x80000004 0x00a551 3
172.16.40.1 172.16.40.1 500 0x80000005 0x00013b 5
172.16.50.1 172.16.50.1 441 0x80000003 0x001023 3
Net Link States (Area 0)
Link ID ADV Router Age Seq# Checksum
172.16.10.1 172.16.10.1 1174 0x80000001 0x00953d
Looks good! The link count for each router makes sense if you count the serial interfaces twice (one for each end).
the OSPF databases now match across all 4 routers.
NOTE that this is a database of routers, identified by
router ID. It is not a topology that lists routers AND routes, like in
the "equivalent" eigrp command show eigrp topology
Note that the .30 network is NOT represented here.
LabA#
show ip ospf database
OSPF Router with ID (172.16.10.1) (Process ID 100)
Router Link States (Area 0)
Link ID ADV Router Age Seq# Checksum Link count
172.16.10.1 172.16.10.1 1138 0x80000002 0x0067cd 1
172.16.20.1 172.16.20.1 686 0x80000004 0x00a551 3
172.16.40.1 172.16.40.1 463 0x80000005 0x00013b 5
172.16.50.1 172.16.50.1 404 0x80000003 0x001023 3
Net Link States (Area 0)
Link ID ADV Router Age Seq# Checksum
172.16.10.1 172.16.10.1 1138 0x80000001 0x00953d
LabB#
show ip ospf database
OSPF Router with ID (172.16.20.1) (Process ID 101)
Router Link States (Area 0)
Link ID ADV Router Age Seq# Checksum Link count
172.16.10.1 172.16.10.1 1151 0x80000002 0x0067cd 1
172.16.20.1 172.16.20.1 699 0x80000004 0x00a551 3
172.16.40.1 172.16.40.1 476 0x80000005 0x00013b 5
172.16.50.1 172.16.50.1 417 0x80000003 0x001023 3
Net Link States (Area 0)
Link ID ADV Router Age Seq# Checksum
172.16.10.1 172.16.10.1 1151 0x80000001 0x00953d
LabC#
show ip ospf database
OSPF Router with ID (172.16.40.1) (Process ID 102)
Router Link States (Area 0)
Link ID ADV Router Age Seq# Checksum Link count
172.16.10.1 172.16.10.1 1174 0x80000002 0x0067cd 1
172.16.20.1 172.16.20.1 722 0x80000004 0x00a551 3
172.16.40.1 172.16.40.1 500 0x80000005 0x00013b 5
172.16.50.1 172.16.50.1 441 0x80000003 0x001023 3
Net Link States (Area 0)
Link ID ADV Router Age Seq# Checksum
172.16.10.1 172.16.10.1 1174 0x80000001 0x00953d
LabD#
show ip ospf database
OSPF Router with ID (172.16.50.1) (Process ID 103)
Router Link States (Area 0)
Link ID ADV Router Age Seq# Checksum Link count
172.16.10.1 172.16.10.1 785 0x80000002 0x0067cd 1
172.16.20.1 172.16.20.1 333 0x80000004 0x00a551 3
172.16.40.1 172.16.40.1 111 0x80000005 0x00013b 5
172.16.50.1 172.16.50.1 53 0x80000003 0x001023 3
Net Link States (Area 0)
Link ID ADV Router Age Seq# Checksum
172.16.10.1 172.16.10.1 785 0x80000001 0x00953d
Below is our routing tables with OSPF data. We do see the .30 network here.
Everyone can reach it:
LabA via LabB's 10.2
LabB via LabC's 20.2
LabC via direct connection
LabD via LabC's 40.1
LabA#
show ip route
172.16.0.0/16 is variably subnetted, 6 subnets, 2 masks
C 172.16.10.0/24 is directly connected, FastEthernet0/0
L 172.16.10.1/32 is directly connected, FastEthernet0/0
O 172.16.20.0/24 [110/65] via 172.16.10.2, 00:28:03, FastEthernet0/0
O 172.16.30.0/24 [110/66] via 172.16.10.2, 00:21:35, FastEthernet0/0
O 172.16.40.0/24 [110/129] via 172.16.10.2, 00:21:25, FastEthernet0/0
O 172.16.50.0/24 [110/130] via 172.16.10.2, 00:17:40, FastEthernet0/0
LabB#
show ip route
172.16.0.0/16 is variably subnetted, 7 subnets, 2 masks
C 172.16.10.0/24 is directly connected, FastEthernet0/0
L 172.16.10.2/32 is directly connected, FastEthernet0/0
C 172.16.20.0/24 is directly connected, Serial0/0/0
L 172.16.20.1/32 is directly connected, Serial0/0/0
O 172.16.30.0/24 [110/65] via 172.16.20.2, 00:27:04, Serial0/0/0
O 172.16.40.0/24 [110/128] via 172.16.20.2, 00:26:54, Serial0/0/0
O 172.16.50.0/24 [110/129] via 172.16.20.2, 00:23:09, Serial0/0/0
LabC#
show ip route
172.16.0.0/16 is variably subnetted, 8 subnets, 2 masks
O 172.16.10.0/24 [110/65] via 172.16.20.1, 00:27:52, Serial0/0/0
C 172.16.20.0/24 is directly connected, Serial0/0/0
L 172.16.20.2/32 is directly connected, Serial0/0/0
C 172.16.30.0/24 is directly connected, FastEthernet0/0
L 172.16.30.1/32 is directly connected, FastEthernet0/0
C 172.16.40.0/24 is directly connected, Serial0/0/1
L 172.16.40.1/32 is directly connected, Serial0/0/1
O 172.16.50.0/24 [110/65] via 172.16.40.2, 00:23:36, Serial0/0/1
LabD#
show ip route
172.16.0.0/16 is variably subnetted, 7 subnets, 2 masks
O 172.16.10.0/24 [110/129] via 172.16.40.1, 00:25:20, Serial0/0/0
O 172.16.20.0/24 [110/128] via 172.16.40.1, 00:25:20, Serial0/0/0
O 172.16.30.0/24 [110/65] via 172.16.40.1, 00:25:20, Serial0/0/0
C 172.16.40.0/24 is directly connected, Serial0/0/0
L 172.16.40.2/32 is directly connected, Serial0/0/0
C 172.16.50.0/24 is directly connected, FastEthernet0/0
L 172.16.50.1/32 is directly connected, FastEthernet0/0
moving on.......
9.5 - OSPF DR and BDR Elections
EachRouter(config)#
hostname X (A, B, or C)
EachRouter(config)#
line con 0
EachRouter(config-line)#
exec-timeout 0 0
A(config)#
int f0/0
A(config-if)#
ip addr 10.1.1.1 255.255.255.0
A(config-if)#
no shut
A(config)#
router ospf 12345
A(config-router)#
net 10.1.1.0 0.0.0.255 area 0
00:23:30: %OSPF-5-ADJCHG: Process 12345, Nbr 10.1.1.3 on FastEthernet0/0 from LOADING to FULL, Loading Done
00:23:30: %OSPF-5-ADJCHG: Process 12345, Nbr 10.1.1.2 on FastEthernet0/0 from LOADING to FULL, Loading Done
A#
show ip ospf int
note this output was generated AFTER all 3 routers set for OSPF
FastEthernet0/0 is up, line protocol is up
Internet address is 10.1.1.1/24, Area 0
Process ID 12345, Router ID 10.1.1.1, Network Type BROADCAST, Cost: 1
Transmit Delay is 1 sec, State DROTHER, Priority 1
Designated Router (ID) 10.1.1.3, Interface address 10.1.1.3
Backup Designated Router (ID) 10.1.1.2, Interface address 10.1.1.2
Timer intervals configured, Hello 10, Dead 40, Wait 40, Retransmit 5
Hello due in 00:00:04
Index 1/1, flood queue length 0
Next 0x0(0)/0x0(0)
Last flood scan length is 1, maximum is 1
Last flood scan time is 0 msec, maximum is 0 msec
Neighbor Count is 2, Adjacent neighbor count is 2
Adjacent with neighbor 10.1.1.3 (Designated Router)
Adjacent with neighbor 10.1.1.2 (Backup Designated Router)
Suppress hello for 0 neighbor(s)
A(config-if)#shut
A(config-if)#
%LINK-5-CHANGED: Interface FastEthernet0/0, changed state to administratively down
%LINEPROTO-5-UPDOWN: Line protocol on Interface FastEthernet0/0, changed state to down
00:40:28: %OSPF-5-ADJCHG: Process 12345, Nbr 10.1.1.2 on FastEthernet0/0 from FULL to DOWN, Neighbor Down: Interface down or detached
00:40:28: OSPF: Build router LSA for area 0, router ID 10.1.1.1, seq 0xffffffff80000003
00:40:28: %OSPF-5-ADJCHG: Process 12345, Nbr 10.1.1.3 on FastEthernet0/0 from FULL to DOWN, Neighbor Down: Interface down or detached
00:40:28: OSPF: Build router LSA for area 0, router ID 10.1.1.1, seq 0xffffffff80000004
00:40:28: OSPF: Build router LSA for area 0, router ID 10.1.1.1, seq 0xffffffff80000004
A(config-if)#no shut
A(config-if)#
%LINK-5-CHANGED: Interface FastEthernet0/0, changed state to up
%LINEPROTO-5-UPDOWN: Line protocol on Interface FastEthernet0/0, changed state to up
00:40:48: OSPF: Build router LSA for area 0, router ID 10.1.1.1, seq 0xffffffff80000004
00:41:27: OSPF: Backup seen Event before WAIT timer on FastEthernet0/0
00:41:27: OSPF: DR/BDR election on FastEthernet0/0
00:41:27: OSPF: Elect BDR 10.1.1.2
00:41:27: OSPF: Elect DR 10.1.1.3
00:41:27: DR: 10.1.1.3 (Id) BDR: 10.1.1.2 (Id)
00:41:27: OSPF: Send DBD to 10.1.1.3 on FastEthernet0/0 seq 0x5accb8e2 opt 0x00 flag 0x7 len 32
B(config)#
int f0/0
B(config-if)#
ip addr 10.1.1.2 255.255.255.0
B(config-if)#
no shut
B(config)#
router ospf 12345
B(config-router)#
net 10.1.1.0 0.0.0.255 area 0
00:23:29: %OSPF-5-ADJCHG: Process 12345, Nbr 10.1.1.3 on FastEthernet0/0 from LOADING to FULL, Loading Done
00:23:29: %OSPF-5-ADJCHG: Process 12345, Nbr 10.1.1.1 on FastEthernet0/0 from LOADING to FULL, Loading Done
B#
show ip ospf int
note this output was generated AFTER all 3 routers set for OSPF
FastEthernet0/0 is up, line protocol is up
Internet address is 10.1.1.2/24, Area 0
Process ID 12345, Router ID 10.1.1.2, Network Type BROADCAST, Cost: 1
Transmit Delay is 1 sec, State BDR, Priority 1
Designated Router (ID) 10.1.1.3, Interface address 10.1.1.3
Backup Designated Router (ID) 10.1.1.2, Interface address 10.1.1.2
Timer intervals configured, Hello 10, Dead 40, Wait 40, Retransmit 5
Hello due in 00:00:05
Index 1/1, flood queue length 0
Next 0x0(0)/0x0(0)
Last flood scan length is 1, maximum is 1
Last flood scan time is 0 msec, maximum is 0 msec
Neighbor Count is 2, Adjacent neighbor count is 2
Adjacent with neighbor 10.1.1.1
Adjacent with neighbor 10.1.1.3 (Designated Router)
Suppress hello for 0 neighbor(s)
B#debug ip ospf adj
OSPF adjacency events debugging is on
B#
00:39:21: OSPF: DR/BDR election on FastEthernet0/0
00:39:21: OSPF: Elect BDR 10.1.1.2
00:39:21: OSPF: Elect DR 10.1.1.3
00:39:21: DR: 10.1.1.3 (Id) BDR: 10.1.1.2 (Id)
00:41:01: %OSPF-5-ADJCHG: Process 12345, Nbr 10.1.1.1 on FastEthernet0/0 from FULL to DOWN, Neighbor Down: Dead timer expired
00:41:01: %OSPF-5-ADJCHG: Process 12345, Nbr 10.1.1.1 on FastEthernet0/0 from FULL to DOWN, Neighbor Down: Interface down or detached
00:41:01: OSPF: Build router LSA for area 0, router ID 10.1.1.2, seq 0xffffffff80000003
00:41:01: OSPF: DR/BDR election on FastEthernet0/0
00:41:01: OSPF: Elect BDR 10.1.1.2
00:41:01: OSPF: Elect DR 10.1.1.3
C(config)#
int f0/0
C(config-if)#
ip addr 10.1.1.3 255.255.255.0
C(config-if)#
no shut
C(config)#
router ospf 12345
C(config-router)#
net 10.1.1.0 0.0.0.255 area 0
00:23:27: %OSPF-5-ADJCHG: Process 12345, Nbr 10.1.1.1 on FastEthernet0/0 from LOADING to FULL, Loading Done
00:23:27: %OSPF-5-ADJCHG: Process 12345, Nbr 10.1.1.2 on FastEthernet0/0 from LOADING to FULL, Loading Done
C#
show ip ospf int
note this output was generated AFTER all 3 routers set for OSPF
FastEthernet0/0 is up, line protocol is up
Internet address is 10.1.1.3/24, Area 0
Process ID 12345, Router ID 10.1.1.3, Network Type BROADCAST, Cost: 1
Transmit Delay is 1 sec, State DR, Priority 1
Designated Router (ID) 10.1.1.3, Interface address 10.1.1.3
Backup Designated Router (ID) 10.1.1.2, Interface address 10.1.1.2
Timer intervals configured, Hello 10, Dead 40, Wait 40, Retransmit 5
Hello due in 00:00:00
Index 1/1, flood queue length 0
Next 0x0(0)/0x0(0)
Last flood scan length is 1, maximum is 1
Last flood scan time is 0 msec, maximum is 0 msec
Neighbor Count is 2, Adjacent neighbor count is 2
Adjacent with neighbor 10.1.1.1
Adjacent with neighbor 10.1.1.2 (Backup Designated Router)
Suppress hello for 0 neighbor(s)
C#debug ip ospf adj
OSPF adjacency events debugging is on
C#
00:39:19: OSPF: DR/BDR election on FastEthernet0/0
00:39:19: OSPF: Elect BDR 10.1.1.2
00:39:19: OSPF: Elect DR 10.1.1.3
00:39:19: DR: 10.1.1.3 (Id) BDR: 10.1.1.2 (Id)
00:40:59: %OSPF-5-ADJCHG: Process 12345, Nbr 10.1.1.1 on FastEthernet0/0 from FULL to DOWN, Neighbor Down: Dead timer expired
00:40:59: %OSPF-5-ADJCHG: Process 12345, Nbr 10.1.1.1 on FastEthernet0/0 from FULL to DOWN, Neighbor Down: Interface down or detached
00:40:59: OSPF: Build router LSA for area 0, router ID 10.1.1.3, seq 0xffffffff80000003
00:40:59: OSPF: Build net LSA for area 0, router ID 10.1.1.3, seq 0xffffffff80000003
00:40:59: OSPF: DR/BDR election on FastEthernet0/0
00:40:59: OSPF: Elect BDR 10.1.1.2
00:40:59: OSPF: Elect DR 10.1.1.3
DR and BDR automtically set based on higest IP address
Note our network type is BROADCAST because we're using ethernet interfaces...
it would be point-to-point if using a serial connection
we want to manually overide the priority of the router. ZERO priority means it wont participate in the election process
MAX priority of 255 means no other router can beat it for DR
We'll set the priority for router A to 3.
It will beome the DR only after we shut/no shut the interface router
AND
manually power on/off the other two routers
A(config)#
int f0/0
A(config-int)#
ip ospf priority 3
A(config-int)#
shut
A(config-int)#
no shut
A#
debug ip ospf adj
B#
debug ip ospf adj
00:05:50: OSPF: DR/BDR election on FastEthernet0/0
00:05:50: OSPF: Elect BDR 10.1.1.2
00:05:50: OSPF: Elect DR 10.1.1.1
00:05:50: OSPF: Elect BDR 10.1.1.2
00:05:50: OSPF: Elect DR 10.1.1.1
00:05:50: DR: 10.1.1.1 (Id) BDR: 10.1.1.2 (Id)
00:05:50: OSPF: Send DBD to 10.1.1.1 on FastEthernet0/0 seq 0x10164ebb opt 0x00 flag 0x7 len 32
00:05:50: OSPF: Build router LSA for area 0, router ID 10.1.1.2, seq 0xffffffff80000002
00:05:52: OSPF: Rcv DBD from 10.1.1.1 on FastEthernet0/0 seq 0x20368093 opt 0x00 flag 0x7 len 32 mtu 1500 state EXSTART
00:05:52: OSPF: First DBD and we are not SLAVE
00:05:55: OSPF: Send DBD to 10.1.1.1 on FastEthernet0/0 seq 0x10164ebb opt 0x00 flag 0x7 len 32
00:05:55: OSPF: Rcv DBD from 10.1.1.1 on FastEthernet0/0 seq 0x10164ebb opt 0x00 flag 0x2 len 112 mtu 1500 state EXSTART
00:05:55: OSPF: NBR Negotiation Done. We are the MASTER
00:05:55: OSPF: Send DBD to 10.1.1.1 on FastEthernet0/0 seq 0x10164ebc opt 0x00 flag 0x3 len 52
00:05:55: OSPF: Rcv DBD from 10.1.1.1 on FastEthernet0/0 seq 0x10164ebc opt 0x00 flag 0x0 len 32 mtu 1500 state EXCHANGE
00:05:55: OSPF: Send DBD to 10.1.1.1 on FastEthernet0/0 seq 0x10164ebd opt 0x00 flag 0x1 len 32
00:05:55: OSPF: Rcv DBD from 10.1.1.1 on FastEthernet0/0 seq 0x10164ebd opt 0x00 flag 0x0 len 32 mtu 1500 state EXCHANGE
00:05:55: Exchange Done with 10.1.1.1 on FastEthernet0/0
00:05:55: OSPF: Database request to 10.1.1.1
00:05:55: OSPF: sent LS REQ packet to 10.1.1.1, length 36
00:05:55: OSPF: Rcv DBD from 10.1.1.1 on FastEthernet0/0 seq 0x10164ebd opt 0x00 flag 0x0 len 32 mtu 1500 state LOADING
00:05:55: Synchronized with with 10.1.1.1 on FastEthernet0/0, state FULL
00:05:55: %OSPF-5-ADJCHG: Process 12345, Nbr 10.1.1.1 on FastEthernet0/0 from LOADING to FULL, Loading Done
00:05:55: OSPF: Build router LSA for area 0, router ID 10.1.1.2, seq 0xffffffff80000002
C#
debug ip ospf adj
00:06:13: OSPF: DR/BDR election on FastEthernet0/0
00:06:13: OSPF: Elect BDR 10.1.1.2
00:06:13: OSPF: Elect DR 10.1.1.1
00:06:13: DR: 10.1.1.1 (Id) BDR: 10.1.1.2 (Id)
00:06:13: OSPF: Send DBD to 10.1.1.1 on FastEthernet0/0 seq 0x1cc5536d opt 0x00 flag 0x7 len 32
00:06:13: OSPF: Send DBD to 10.1.1.2 on FastEthernet0/0 seq 0x3d51ca66 opt 0x00 flag 0x7 len 32
00:06:13: OSPF: Build router LSA for area 0, router ID 10.1.1.3, seq 0xffffffff80000002
00:06:17: OSPF: Rcv DBD from 10.1.1.1 on FastEthernet0/0 seq 0x6b532eec opt 0x00 flag 0x7 len 32 mtu 1500 state EXSTART
00:06:17: OSPF: First DBD and we are not SLAVE
00:06:17: OSPF: Rcv DBD from 10.1.1.2 on FastEthernet0/0 seq 0x783110f4 opt 0x00 flag 0x7 len 32 mtu 1500 state EXSTART
00:06:17: OSPF: First DBD and we are not SLAVE
00:06:18: OSPF: Send DBD to 10.1.1.2 on FastEthernet0/0 seq 0x3d51ca66 opt 0x00 flag 0x7 len 32
00:06:18: OSPF: Send DBD to 10.1.1.1 on FastEthernet0/0 seq 0x1cc5536d opt 0x00 flag 0x7 len 32
00:06:18: OSPF: Rcv DBD from 10.1.1.2 on FastEthernet0/0 seq 0x3d51ca66 opt 0x00 flag 0x2 len 132 mtu 1500 state EXSTART
00:06:18: OSPF: NBR Negotiation Done. We are the MASTER
00:06:18: OSPF: Send DBD to 10.1.1.2 on FastEthernet0/0 seq 0x3d51ca67 opt 0x00 flag 0x3 len 52
00:06:18: OSPF: Rcv DBD from 10.1.1.1 on FastEthernet0/0 seq 0x1cc5536d opt 0x00 flag 0x2 len 132 mtu 1500 state EXSTART
00:06:18: OSPF: NBR Negotiation Done. We are the MASTER
00:06:18: OSPF: Send DBD to 10.1.1.1 on FastEthernet0/0 seq 0x1cc5536e opt 0x00 flag 0x3 len 52
00:06:18: OSPF: Rcv DBD from 10.1.1.2 on FastEthernet0/0 seq 0x3d51ca67 opt 0x00 flag 0x0 len 32 mtu 1500 state EXCHANGE
00:06:18: OSPF: Send DBD to 10.1.1.2 on FastEthernet0/0 seq 0x3d51ca68 opt 0x00 flag 0x1 len 32
00:06:18: OSPF: Rcv DBD from 10.1.1.1 on FastEthernet0/0 seq 0x1cc5536e opt 0x00 flag 0x0 len 32 mtu 1500 state EXCHANGE
00:06:18: OSPF: Send DBD to 10.1.1.1 on FastEthernet0/0 seq 0x1cc5536f opt 0x00 flag 0x1 len 32
00:06:18: OSPF: Rcv DBD from 10.1.1.2 on FastEthernet0/0 seq 0x3d51ca68 opt 0x00 flag 0x0 len 32 mtu 1500 state EXCHANGE
00:06:18: Exchange Done with 10.1.1.2 on FastEthernet0/0
00:06:18: OSPF: Database request to 10.1.1.2
00:06:18: OSPF: sent LS REQ packet to 10.1.1.2, length 48
00:06:18: OSPF: Rcv DBD from 10.1.1.1 on FastEthernet0/0 seq 0x1cc5536f opt 0x00 flag 0x0 len 32 mtu 1500 state EXCHANGE
verify on all three routers
A#
show ip ospf interface f0/0
FastEthernet0/0 is up, line protocol is up
Internet address is 10.1.1.1/24, Area 0
Process ID 12345, Router ID 10.1.1.1, Network Type BROADCAST, Cost: 1
Transmit Delay is 1 sec, State DR, Priority 3
Designated Router (ID) 10.1.1.1, Interface address 10.1.1.1
Backup Designated Router (ID) 10.1.1.2, Interface address 10.1.1.2
Timer intervals configured, Hello 10, Dead 40, Wait 40, Retransmit 5
Hello due in 00:00:09
Index 1/1, flood queue length 0
Next 0x0(0)/0x0(0)
Last flood scan length is 1, maximum is 1
Last flood scan time is 0 msec, maximum is 0 msec
Neighbor Count is 2, Adjacent neighbor count is 2
Adjacent with neighbor 10.1.1.2 (Backup Designated Router)
Adjacent with neighbor 10.1.1.3
Suppress hello for 0 neighbor(s)
A#
show ip ospf neighbor
Neighbor ID Pri State Dead Time Address Interface
10.1.1.2 1 FULL/BDR 00:00:37 10.1.1.2 FastEthernet0/0
10.1.1.3 1 FULL/DROTHER 00:00:30 10.1.1.3 FastEthernet0/0
B#
show ip ospf interface f0/0
FastEthernet0/0 is up, line protocol is up
Internet address is 10.1.1.2/24, Area 0
Process ID 12345, Router ID 10.1.1.2, Network Type BROADCAST, Cost: 1
Transmit Delay is 1 sec, State BDR, Priority 1
Designated Router (ID) 10.1.1.1, Interface address 10.1.1.1
Backup Designated Router (ID) 10.1.1.2, Interface address 10.1.1.2
Timer intervals configured, Hello 10, Dead 40, Wait 40, Retransmit 5
Hello due in 00:00:08
Index 1/1, flood queue length 0
Next 0x0(0)/0x0(0)
Last flood scan length is 1, maximum is 1
Last flood scan time is 0 msec, maximum is 0 msec
Neighbor Count is 2, Adjacent neighbor count is 2
Adjacent with neighbor 10.1.1.1 (Designated Router)
Adjacent with neighbor 10.1.1.3
Suppress hello for 0 neighbor(s)
B#
show ip ospf neighbor
Neighbor ID Pri State Dead Time Address Interface
10.1.1.1 3 FULL/DR 00:00:35 10.1.1.1 FastEthernet0/0
10.1.1.3 1 FULL/DROTHER 00:00:31 10.1.1.3 FastEthernet0/0
C#
show ip ospf interface f0/0
FastEthernet0/0 is up, line protocol is up
Internet address is 10.1.1.3/24, Area 0
Process ID 12345, Router ID 10.1.1.3, Network Type BROADCAST, Cost: 1
Transmit Delay is 1 sec, State DROTHER, Priority 1
Designated Router (ID) 10.1.1.1, Interface address 10.1.1.1
Backup Designated Router (ID) 10.1.1.2, Interface address 10.1.1.2
Timer intervals configured, Hello 10, Dead 40, Wait 40, Retransmit 5
Hello due in 00:00:06
Index 1/1, flood queue length 0
Next 0x0(0)/0x0(0)
Last flood scan length is 1, maximum is 1
Last flood scan time is 0 msec, maximum is 0 msec
Neighbor Count is 2, Adjacent neighbor count is 2
Adjacent with neighbor 10.1.1.1 (Designated Router)
Adjacent with neighbor 10.1.1.2 (Backup Designated Router)
Suppress hello for 0 neighbor(s)
C#
show ip ospf neighbor/span>
Neighbor ID Pri State Dead Time Address Interface
10.1.1.1 3 FULL/DR 00:00:35 10.1.1.1 FastEthernet0/0
10.1.1.2 1 FULL/BDR 00:00:37 10.1.1.2 FastEthernet0/0
Router1 is the DR with priority 3
still need more work to understand the output of the defbu ospf adj
Chapter 9 Review Questions
1. There are three possible routes for a router to reach a destination network:
OSPF with a metric of 782
RIPv2 with a metric of 4
EIGRP with a composite metric of 20514560
Which route will be installed in the routing table?
EIGRP because it has the lowest Administrative Distance, and AD is always used before metric
ADs are:
ExternalEIGRP 170
RIP 120
OSPF 110
IGRP 100
EIGRP 90
Static 1
Connected 0
2. Which EIGRP information is held in RAM and maintained through the use of Hello and update packets?
Neighbor table
and
toplogy table
3. Describe the process identifier that is used to run OSPF on a router
The OSPF process id is only locally significant. A random number can be selected. But it's required in order to identify
a unique OSPF database instance. You can use the same, or a different number on each router, doesnt matter.
Any number can be used from 1 to 65,535. Process ID is supplied as an argument to the command router ospf
NOT to be confused with the area number which can be any number up to 4 billion. The area id identifies a logical grouping of routers.
area id is supplied as argument to the OSPF network id and mask command
Ex:
R1(config)#
router ospf 12345
R1(config-router)#
net 10.1.1.0 0.0.0.255 area 0
4. Where are EIGRP successor routes stored?
EIGRP succesor routers are stored in the routing table. The "succesor" is the successful or primary route.
The successor route is ALSO listed in the topology table,
The feasible successor is a BACKUP route and will ONLY be listed in the topology table, unless the successor route fails,
in which case the feasible successor would become the successor
Note that my EIGRP setup doesnt seem to folow this.
CTRL-F jump to "remotely connected via remote ingress ip address"
the book states that EIGRP is automatically load-balancing our two links from R1 to corp.. is this why there is no feasible successor here?
I did some research and found that in our case, we are not using a Feasible Successor. You CAN have two Successors with equal metric, in which case EIGRP will
automatically load-balance.
But I wanted to find out what a Feasible Successor actually looks like in the EIGRP topology table..
Kevin Wallace EIGRP article
Conclusion:
EIGRP topology table wouldnt specifically say "Feasible Successor", but you would know by two routes appearing, one with a lower metric.
In my topology we have two equal-metric links and they are both considered "Successors". EIGRP uses them equally (load-balanced)
Corp#
show ip eigrp toplogy
[cut]
P 172.16.10.0/24, 1 successors, FD is 28160
via 10.1.5.2 (28160/25600), FastEthernet0/0
P 192.168.10.0/24, 2 successors, FD is 2172416
via 10.1.3.2 (2172416/28160), Serial0/0/1
via 10.1.2.2 (2172416/28160), Serial0/0/0
P 192.168.20.0/24, 2 successors, FD is 2172416
via 10.1.3.2 (2172416/28160), Serial0/0/1
via 10.1.2.2 (2172416/28160), Serial0/0/0
P 192.168.30.0/24, 1 successors, FD is 2172416
via 10.1.4.2 (2172416/28160), Serial0/1/0
P 192.168.40.0/24, 1 successors, FD is 2172416
via 10.1.4.2 (2172416/28160), Serial0/1/0
5. Which command will display all the EIGRP feasible successor routes to a known router.
show ip eigrp topology
6. Find the configuration error. You type the following into your router, but dont see any routes in the routing table?
Router(config)#
router ospf 1
Router(config-router)#
network 10.0.0.0 255.0.0.0
wrong wildcard mask
instead, could have used
0.255.255.255
or
0.0.0.255
the point is we need to specify the first octet as "allowed" into our OSPF config with a 0 mask.
The remaining bits are 'dont care' bits aka 'wildcard' aka 255
7. Which three protocols support VLSM, summarization, and discontigous networking?
RIPv2
EIGRP
OSPF
all 3 build and mainting routing tables, provide classless routing which allows VLSM, summarization, and discontigous networks
RIPv1 and IGRP build/maintain routing tables, but dont offer classless routing
8. Which are true regarding OSPF areas?
the 'backbone' is area 0
if using other areas, they all must directly connect to area 0
9. Which two network types have a designated router and a backup designated router?
Broadcast
NBMA- Non broadcast multi access. Ex: Frame Relay
network types that DO NOT use DR/BDR:
point to point
broadcast multipoint
10. You need to configure a router with a distance-vector protocol that allows classless routing. Which to use?
EIGRP is considered 'advanced distance vector' (ripv2 wasnt an option)
11. You need the IP address of the devices with which the router has established an adjacency.
Also, the retransmit interval and the queue counts for the adjacent routers need to be checked. What command will display the required information?
show ip eigrp neighbors
WRONG: show ip eigrp adjacency - there is no such command.. the word 'adjacency' is only used with debug ip OSPF adjacency
here are the possible commands for show ip eigrp and debug ip eigrp
show ip eigrp ?
interfaces IP-EIGRP interfaces
neighbors IP-EIGRP neighbors
topology IP-EIGRP Topology Table
traffic IP-EIGRP Traffic Statistics
debug ip eigrp ?
summary IP-EIGRP summary route processing
12. You cant establish an adjacency relationship on a common ethernet link between two routers. Based on the output below, what is the cause of the problem?
RouterA#
Ethernet0/0 is up, line protocol is up
Internet Address 172.16.1.2/16, Area 0
Process ID 2, Router ID 172.126.1.2, Network Type BROADCAST, Cost: 10
Transmit Delay is 1 sec, State DR, Priority 1
Designated Router (ID) 172.16.1.2, interface address 172.16.1.1.
No backup designated router on this network
Timer intervals configured, Hello 5, Dead 20, Wait 20, Retransmit 5
Router B#
Internet Address 172.16.1.1/16, Area 0
Process ID 2, Router ID 172.126.1.1, Network Type BROADCAST, Cost: 10
Transmit Delay is 1 sec, State DR, Priority 1
Designated Router (ID) 172.16.1.1, interface address 172.16.1.2.
No backup designated router on this network
Timer intervals configured, Hello 10, Dead 40, Wait 40, Retransmit 5
mismatched timer intervals
OSPF default Hello is 10 and Dead is 40... RouterA was modified
13. Which is true regarding EIGRP successor routes?
Used in the routing table
also appears in the topolgy table
may (or may not) have a backup feasabile successor
14. Which type of OSPF network will elect a backup designated router?
broadcast multi-access
non-broadcast multiaccess
types of network that will NOT elect a BDR:
point to point and brodacast multipoint (hub/spoke topology)
15. Which two commands will place network 10.2.3.0/24 into area 0?
Router(config)#
router ospf 10
Router(config-router)#
network 10.2.3.0 0.0.0.255 area 0
16. With which network type will OSPF establish router adjacencies but not perform the DR/BDR election process?
Point to point
no election process occurs, there is never a DR on point to point
17. What are three reasons for creating OSPF in a heirarchical design?
decrease routing overhead
speed up convergence
confine stability to single areas of the network
18. What is the administrative distance of OSPF?
110
19.
no auto summary
the network is considered discontigous because we have two classful network subnetted (on the left and right),
seperated by a different classful address.
if auto summarization is taking place, the routers cant determine which side is which because both sides would be summarized as
Class B, 172.16.0.0, which isnt specific enough to distinguish between the sides.
20. IF routers in a single area are configured with the same priority value, what value does a router use for the OSPF router ID in the absence of a loopback interface?
The highest IP of any PHSYICAL interface.
Trick question. Highest IP of any LOGICAL interface is an option. And is correct IF you had logical interfaces, but the question
states that any "logical interfaces are absent".
At OSPF startup, the highest IP of *any* active interface on the router becomes the OSPF router ID. If you have loopback (logical) interfaces configured,
one of them (the largest IP) will *override* the phsyical interfaces and the loopback IP becomes the RID.
Reference for which loopback (if multiple) wins:
packetpushers.net
------------------------------------------------------------------------------
END CHAPTER 9
41 hours 2-14 thru 2-28-22
original total 184 hours
14 hours review 12-26 thru 12-28-22
review total hours 46
book page 502/822
184 + 46 = 230 hours * 60 = (13,800 min) / 500 pages =
avg 28 min/page (includes reading and exercises/labs + online research)
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1. Cisco IOS
flash
2. Bootstrap
ROM
3. Startup configuration
NVRAM
4. POST
ROM
5. Running configuration
RAM
6. ARP cache
RAM
7. Mini IOS
ROM
8. ROM Monitor
ROM
9. Routing tables
RAM
10. packet buffers
RAM
Here is the topology:
Server Configuration
ipv4 address: 193.1.1.2
subnet mask: 255.255.255.248
default gateway: 193.1.1.1
Switch Configuration
SW1# interface range f0/1-2
SW1(config-if-range)# no shut
Router Configurations
R1(config)# int g0/0/0
R1(config)# ip addr 193.1.1.9 255.255.255.248
R1(config)# no shut
R1(config)# int g0/0/1
R1(config)# ip addr 193.1.1.1 255.255.255.248
R1(config)# no shut
the server's default gateway
R2(config)# int g0/0/0
R2(config)# ip addr 193.1.1.10 255.255.255.248
R2(config)# no shut
R2(config)# int g0/0/1
R2(config)# ip addr 193.1.1.17 255.255.255.248
R2(config)# no shut
R3(config)# int g0/0/0
R3(config)# ip addr 193.1.1.18 255.255.255.248
R3(config)# no shut
the segment between R1 and the server
network 193.1.1.0/29
block of 8
hosts .1, .2
the segment between R1 and R2
network 193.1.1.8/29
block of 8
hosts .9 , .10
the segment between the R2 and R3
network 193.1.1.16/29
block of 8
hosts .17 , .18
THIS IS INCORRECT!!!!
I have misunderstood the instructions.
I have misunderstood the instructions.
the problem with this topology is that packets cannot pass through the routers. We dont have any ROUTING setup. ROUTING is covered in the next chapter.
For these labs, we dont need routing, but we need multiple routers to demo telnet and CDP. Here are the instructions:
my mistake was not putting all router interfaces in the same subnet. I tried to do this initially, but it wouldnt work because I had the routers linked together rather than connected by a switch.
The instructions say:
"Your PC and the router(s) are connected together with a switch"
this is the part I missed. The pc and all router interfaces should be on the same switch and the same network
The instructions say:
"Your PC and the router(s) are connected together with a switch"
this is the part I missed. The pc and all router interfaces should be on the same switch and the same network
Here is the corrected topology
Server Configuration
ipv4 address: 193.1.1.4
subnet mask: 255.255.255.248
default gateway: 193.1.1.1
Switch Configuration
SW1# interface range f0/1-4
SW1(config-if-range)# no shut
Router Configurations
R1(config)# int g0/0/0
R1(config)# ip addr 193.1.1.1 255.255.255.248
R1(config)# no shut
the server's default gateway
R2(config)# int g0/0/0
R2(config)# ip addr 193.1.1.2 255.255.255.248
R2(config)# no shut
R3(config)# int g0/0/0
R3(config)# ip addr 193.1.1.3 255.255.255.248
R3(config)# no shut
Chapter 7 Hands-on Lab 7.1 Backing up your router IOS
1. verify connection to the server
R1#
ping 193.1.1.1
Type escape sequence to abort.
Sending 5, 100-byte ICMP Echos to 193.1.1.2, timeout is 2 seconds:
.!!!!
Success rate is 80 percent (4/5), round-trip min/avg/max = 0/1/5 ms
2. show contents of flash memory
R1#
show flash
System flash directory:
File Length Name/status
3 486899872isr4300-universalk9.16.06.04.SPA.bin
2 28282 sigdef-category.xml
1 227537 sigdef-default.xml
[487155691 bytes used, 2761893909 available, 3249049600 total]
3.17338e+06K bytes of processor board System flash (Read/Write)
show flash gives ALL of the files in flash memory
show version gives the current running file
3. show the IOS currently running
R1#
show version
Cisco IOS XE Software, Version 03.16.05.S - Extended Support Release
[cut]
ROM: IOS-XE ROMMON
Router uptime is 9 minutes, 39 seconds
Uptime for this control processor is 9 minutes, 39 seconds
System returned to ROM by power-on
System image file is "bootflash:/isr4300-universalk9.03.16.05.S.155-3.S5-ext.SPA.bin"
Last reload reason: PowerOn
[cut]
note that the file that is currently running is NOT located in the flash storage!!!
4. backup IOS from router to server
R1#
copy flash tftp
Source filename []?isr4300-universalk9.16.06.04.SPA.bin
Address or name of remote host []? 193.1.1.4
Destination filename [isr4300-universalk9.16.06.04.SPA.bin]? ENTER
Writing isr4300-universalk9.16.06.04.SPA.bin...!!!!!!!!!!!!!!!
[OK - 486899872 bytes]
486899872 bytes copied in 12.526 secs (125224 bytes/sec)
Chapter 7 Hands-on Lab 7.2 Upgrading or restoring your router IOS
1. verify connection to the server
R1#
ping 193.1.1.4
Type escape sequence to abort.
Sending 5, 100-byte ICMP Echos to 193.1.1.2, timeout is 2 seconds:
!!!!!
Success rate is 100 percent (5/5), round-trip min/avg/max = 0/0/1 ms
2. copy from tftp sever to flash
R1#
copy tftp flash TFTP comes first in the command since we are pulling from TFTP server.
In this command, remot host address is required before file name
Address or name of remote host []? 193.1.1.4
Source filename []?isr4300-universalk9.16.06.04.SPA.bin
Destination filename [isr4300-universalk9.16.06.04.SPA.bin]? ENTER
%Warning:There is a file already existing with this name
Do you want to over write? [confirm]
Accessing tftp://193.1.1.4/isr4300-universalk9.16.06.04.SPA-12-23-22...
Loading isr4300-universalk9.16.06.04.SPA-12-23-22.bin from 193.1.1.4: !!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!
[OK - 486899872 bytes]
486899872 bytes copied in 12.785 secs (122688 bytes/sec)
Chapter 7 Hands-on Lab 7.3 Backing up the router configuration
1. verify connection to the server
R1#
ping 193.1.1.2
Type escape sequence to abort.
Sending 5, 100-byte ICMP Echos to 193.1.1.4, timeout is 2 seconds:
!!!!!
Success rate is 100 percent (5/5), round-trip min/avg/max = 0/0/1 ms
2. copy running-confing to server
R1#
copy run tftp
Address or name of remote host []? 193.1.1.4
Destination filename [R1-confg]?ENTER "R1-confg" is the default name
Writing running-config...!!
[OK - 668 bytes]
668 bytes copied in 0.004 secs (167000 bytes/sec)
Chapter 7 Hands-on Lab 7.4 Using the Cisco Discovery Protocol (CDP)
R1#
show cdp
Global CDP information:
Sending CDP packets every 60 seconds
Sending a holdtime value of 180 seconds
Sending CDPv2 advertisements is enabled
R1#
show cdp interface
Vlan1 is administratively down, line protocol is down
Sending CDP packets every 60 seconds
Holdtime is 180 seconds
GigabitEthernet0/0/0 is up, line protocol is up
Sending CDP packets every 60 seconds
Holdtime is 180 seconds
GigabitEthernet0/0/1 is administratively down, line protocol is down
Sending CDP packets every 60 seconds
Holdtime is 180 seconds
GigabitEthernet0/0/2 is administratively down, line protocol is down
Sending CDP packets every 60 seconds
Holdtime is 180 seconds
R1#
show cdp entry *
Device ID: SW1
Entry address(es):
Platform: cisco 2960, Capabilities: Switch
Interface: GigabitEthernet0/0/0, Port ID (outgoing port): FastEthernet0/1
NOTE g0/0/0 is the outgoing port on this router, F0/1 is the port on the switch at other end
Holdtime: 157
Version :
Cisco IOS Software, C2960 Software (C2960-LANBASEK9-M), Version 15.0(2)SE4, RELEASE SOFTWARE (fc1)
Technical Support: http://www.cisco.com/techsupport
Copyright (c) 1986-2013 by Cisco Systems, Inc.
Compiled Wed 26-Jun-13 02:49 by mnguyen
advertisement version: 2
Duplex: full
R1#
show cdp entry neighbors
[no output]
R1#
show cdp neighbors detail
Device ID: SW1
Entry address(es):
Platform: cisco 2960, Capabilities: Switch
Interface: GigabitEthernet0/0/0, Port ID (outgoing port): FastEthernet0/1
Holdtime: 178
Version :
Cisco IOS Software, C2960 Software (C2960-LANBASEK9-M), Version 15.0(2)SE4, RELEASE SOFTWARE (fc1)
Technical Support: http://www.cisco.com/techsupport
Copyright (c) 1986-2013 by Cisco Systems, Inc.
Compiled Wed 26-Jun-13 02:49 by mnguyen
advertisement version: 2
Duplex: full
Chapter 7 Hands-on Lab 7.5 Using Telnet
enable telnet on R2 and set password
R2(config)#
line vty 0 15
R2(config-line)#
password telnet
R2(config-line)#
login
enable telnet on R3 and set password
R3(config)#
line vty 0 15
R3(config-line)#
password telnet
R3(config-line)#
login
note that the result of this command on each router, by default,
is to present all 15 lines in TWO SEPERATE chunks: 0-4 and 5-15
R3#
show run
[cut]
!
!
!
line con 0
!
line aux 0
!
line vty 0 4
password telnet
login
line vty 5 15
password telnet
login
!
!
!
end
--------------------------------------------------------------------------------
connect to R2 from R1
R1#
telnet 193.1.1.2
Trying 193.1.1..2 ...Open
User Access Verification
Password: telnet
prompt changes to R2 to indicate we are remoted in
R2>
exit the session
ctrl + shift + 6, x
prompt changes back to R1
R1#
--------------------------------------------------------------------------------
connect to R3 from R1
R1#
193.1.1.3 note that the word 'telnet' is not required bc we are still in telnet mode
Trying 193.1.1..3 ...Open
User Access Verification
Password: telnet
prompt changes to R3 to indicate we are remoted in
R3>
exit the session
ctrl + shift + 6, x
prompt changes back to R1
R1#
--------------------------------------------------------------------------------
We have exited the sessions, but they are still open
R1#
show sessions
Conn Host Address Byte Idle Conn Name
1 193.1.1.2 193.1.1.2 0 0 193.1.1.2
* 2 193.1.1.3 193.1.1.3 0 0 193.1.1.3
two telnet sessions- notice that the 'conn number' doesnt correspond to ip address in any way.
R1#
show users
Line User Host(s) Idle Location
* 0 con 0 193.1.1.2 00:00:03
193.1.1.3 00:00:43
this is saying one user is on this router, with two outbound connections (but it isnt showing that they are vty connections)
... they must both be considered 'console' connections outbound and are not considered 'vty' until they are received inbound
the asterisk means something different here than above... doesnt mean default(most recent)session... what does it mean?
back to R2
R2#
show users
Line User Host(s) Idle Location
* 4 vty 0 idle 00:00:00 193.1.1.1
Interface User Mode Idle Peer Address
this is saying that there is one (unnamed) user remoted in via line vty 4
back to R3
R3#
show users
Line User Host(s) Idle Location
* 4 vty 0 idle 00:00:00 193.1.1.1
Interface User Mode Idle Peer Address
this is saying that there is one (unnamed) user remoted in via line vty 4
-------------------------------------------------------------------------------------
Important Considerations:
-
asterisk indicates default session
-
when telnetting in, you will be in user mode. If there is no password already set for PRIVILEGED MODE, you will be unable to enter
-
be careful with 'exit'. it will exit the telnet session if you exit at priv. mode. Use 'disable' to leave priv mode.
-
after 'suspending' a session with ctrl+shift+6,x and youre back at your original priv. prompt, do not press enter to create line breaks-
rather than break lines as usual, the keystroke will cause this:
[Resuming connection 1 to 193.1.1.2 ... ]
prompt will sit here until you strike enter again, then you'll return to that session. What is actually happening is that
youre connecting to the 'default' telnet connection. The same behavior happens when youre at the 'show sessions' screen.
Even if you are not viewing active sessions, the enter key(twice) will connect you to the default session
-
you can use disconnect or exit to end a session
-
Ex: disconnect 1 at the show sessions screen
Chapter 7 Hands-on Lab 7.6 Resolving Hostnames
We're going to build a host table on R1 so we can connect to the other routers via hostname rather than type in the IP address
the command is ip host name arg ip arg
R1(config)#
ip host R2 193.1.1.2
R1(config)#
ip host R3 193.1.1.3
Now if we enter R2 or telnet R2 we get the telnet prompt
R1# R2
Trying 193.1.1.2 ...Open
User Access Verification
Password:
same for the PING command
R1# ping R2
Type escape sequence to abort.
Sending 5, 100-byte ICMP Echos to 193.1.1.2, timeout is 2 seconds:
!!!!!
Success rate is 100 percent (5/5), round-trip min/avg/max = 0/0/2 ms
R1#
show hosts
Default Domain is not set
Name/address lookup uses domain service
Name servers are 255.255.255.255
Codes: UN - unknown, EX - expired, OK - OK, ?? - revalidate
temp - temporary, perm - permanent
NA - Not Applicable None - Not defined
Host Port Flags Age Type Address(es)
R2 None (perm, OK) 0 IP 193.1.1.2
R3 None (perm, OK) 0 IP 193.1.1.3
R1#
telnet R2
R2>
CTRL + SHIFT + 6, X
R1#
telnet R3
R3>
CTRL + SHIFT + 6, X
R1#
show session
Conn Host Address Byte Idle Conn Name
1 R2 193.1.1.2 0 0 R2
* 2 R3 193.1.1.3 0 0 R3
Chapter 7 Review Questions
1. What does the command
confreg 0x2142
provide?
bypass startup-config, to allow password reset
2. Which command will copy the IOS to a backup host on your network?
copy flash tftp
3. You are troubleshooting a connectivity problem in your corporate network and want to isolate the problem. You suspect that a router on the route to an unreachable
network is at fault. What IOS user exec command should you issue?
traceroute
note this is not a priviliged mode command; it can be run from user mode
4. You copy a configuration from a network host to a router's RAM. The configuration looks correct, yet it is no working at all. What could the problem be?
when you perform a copy from a network host to a router, the interfaces are automatically shut down and have to be manually enabled with no shutdown
5. A network administrator wants to upgrade the IOS of a router without removing the image currently installed. What command will display the amount of memory consumed by the
current IOS image and indicate whether there is enough room available to hold both the current and new images?
show flash
6. The corporate office sends you a new router to connect, but upon connecting the console cable, you see that there is already a configuration on the router.
What should be done before a new configuration is entered in the router?
erase NVRAM and restart the router
erase startup-config
reload
7. Which command loads a new version of the Cisco IOS into a router?
copy tftp flash
8. Which command will show you the IOS version running on your router?
show version
9. What should the configuration register value be after you successfully complete the password recovery procedure and return the router to normal operation?
0x2102
10. You save the configuration on a router with the
copy running-config startup-config
command and reboot the router. The router, however, comes up with a blank configuration. What can the problem be?
wrong config register causing you to bypass startup-confing in NVRAM
11. If you want to have more than one Telnet session open at the same time, what keystroke combination would you use?
CTRL+SHIFT+6, X
12. You are unsuccessful in telnetting into a remote device, but you could telnet to the router earlier, However, you can still ping the remote device.
What can the problem be?
access control list could be filtering telnet
OR
the VTY password may not be set on the target
13. What information is displayed by the
show hosts
command?
gives info on temporary DNS entries and permanent name-to-address mappings created using the ip host command
14. Name three commands that can be used to check LAN connectivity problems on a router?
trace
show interfaces
show ip route
15. You telnet to a router and make your necessary changes; now you want to end the Telnet session. What command do you type in?
exit
16. You telnet into a remote device and type
debug ip rip
but no output from the
debug
command is seen. What could the problem be?
to see console messages through a telnet session, you must enter the command terminal monitor
17. Which command displays the configuration register setting?
show version
18. You need to gather the IP address of a remote switch that is located in Hawaii. What can you do to find the address?
show cdp neighbors detail
19. You have your laptop directly connected into a router's Ethernet port. Which are requirements for the
copy flash tftp
command to be successful?
have a TFTP server running on the laptop
laptop must have an IP on the same subnet as the router interface
give the IP address of the laptop when asked after entering the command
20. The configuration register setting of 0x2102 provides what function to a router?
points to NVRAM for startup-configuration AND boot sequence
END CHAPTER 7
26 hours 1-19 thru 1-26-22
original total hours 89
7 hours review 12-23-22
review total hours 20.5
book page 344/822
avg 15 min/page (reading and exercises/labs)
Chapter 8 Exercises
pg 374
before I begin to configure this network, I want to look closer at the HARDWARE
Todd mentions these routers:
2811 with four serial interfaces and switch module or wireless card
1841
while the book was published in 2011, both routers appear to be available in 2021 packet tracer,
but both are considered legacy as of Feb 2022.
The 2811:
The 1841:
we're going to need to understand the MODULES. What are these?
a few examples:
NM-1E is a 1-port ethernet module
NM-1FE-TX is a fast ethernet module
NM-8A/s is an Eight Port Async/Sync Network Module
HWIC-2T is a 2-port serial WAN interface card
HWIC-AP-AG-B is a wireless card
What is an "NM module"?
A network module is a software module that implements a specific
function in a network stack, such as a data link interface, a transport protocol,
or a network application.
What is a "HWIC module"?
A high-speed WAN interface card
Here is a look inside a real 2811:
Back to the requirements for our lab- Todd says the 2811 'Corp' router needs a switch module
and four serial interfaces. NOTE the book doesnt give specifics on how to create the topology in Packet Tracer.
Our Packet Tracer 2811 offers these modules:
The NM-ESW-16 appears to be the only 'switch module', so I will add that.
And the HWIC-2T is a 2-Port Serial High-Speed WAN Interface Card, providing 2 serial ports.
I will add two of these.
next: R3, which needs to be a 2811 with a wirless card. I will add the HWIC-AP-AG-B:
The HWIC-AP-AG-B module is a High-Speed WAN Interface Card providing integrated Access Point
functionality in the Cisco 1800 (Modular), Cisco 2800,
and Cisco 3800 Integrated Services Routers.
It supports Single Band 802.11b/g or Dual Band 802.11a/b/g radios.
our router hardware is in place:
and here is where we need to end up
Next we need to figure out how to connect the server farm to the switch card on R1:
if I use the auto-select cable, I get a copper crossover cable connecting at fa0/0 on the router.
Per the diagram fa0/0 should
connect to R3. I need to connect the servers to the switch card on R1.
Instead of using the auto-select cable, I'll try a straight-through cable.
Success. While the auto-select cable did not give me an option as to what port it will connect to, I did get the option when
manually applying the straight-through cable. Instead of connecting to F0/0 which would require a crossover-cable(computer to router),
I will connect to the integrated switch at port F1/0, then connect the other two servers to F1/1 and F1/2, respectively.
Also worth noting: the Physical Device diagrams in Packet Tracer do not show cables plugged into the ports.
We are relying on the labels on the logical diagram to see which cables are plugged into which ports...
As far as how we can tell what is connected from within the CLI.. I dont know right now.
Now I will connect the other routers. Here is the chart specifiying what interfaces should be used:
Router
Network Address
Interface
Address
CORP
10.1.1.0
Vlan1 (switch card)
10.1.1.1
10.1.2.0
S0/0/0
10.1.2.1
10.1.3.0
S0/0/1 (DCE)
10.1.3.1
10.1.4.0
S0/1/0
10.1.4.1
10.1.5.0
F0/0
10.1.5.1
R1
10.1.2.0
S0/0/0 (DCE)
10.1.2.2
10.1.3.0
S0/0/1
10.1.3.2
192.168.10.0
F0/0
192.168.10.1
192.168.20.0
F0/1
192.168.20.1
R2
10.1.4.0
S0/0/0 (DCE)
10.1.4.2
192.168.30.0
F0/0
192.168.30.1
192.168.40.0
F0/0
192.168.40.1
R3
10.1.5.0
F0/0
10.1.5.2
172.16.10.0
Dot11Radio0/0/0
172.16.10.1
PROBLEM
The R1 router doesnt appear to have any serial interfaces
I will add an HWIC-2T card to both R1 and R2 since the diagram calls for serial interfaces.
The HWIC-2T is a Cisco 2-Port Serial High-Speed WAN Interface Card, providing 2 serial ports.
PROBLEM
The Corp router is not showing the expected available interfaces. I need to connect R1 to the S0/0/0 interface on Corp and R2 to the S0/0/1 interface on Corp.
My Corp router is not showing those interfaces:
Solution
the placement of the cards on the router determines which interface numbers will be available.
In this case, it seems the interfaces start from the bottom right corner and increase on each slot moving clockwise. I found this out by filling all four slots on my router
which led to all interfaces being available. I then ran a card in each slot individually to isolate which interface numbers correspond to each slot:
Interestingly, while the physical slots seem to follow a 'clockwise' pattern, the list of available slots in the logical diagram does not;
We get an output of interfaces corresponding to slot 2, then 3, 1, and 4. This is a 'bottom to top' then 'left to right' pattern. Tricky.
Having said all that... I will run cards in slots 1 and 2 for this lab since we only need interfaces S0/0/0, S0/0/1, S0/1/0
The Router topology:
I'm not clear on the connections from R1 and R2 to the clients.. I assume there are switches involved.
For now I will follow the next steps in the book which
are to configure the corp router as follows:
Router(config)#
hostname Corp
Corp(config)#
enable secret todd
Corp(config)#
interface vlan 1
Corp(config-if)#
description Switch Card to Core Network
Corp(config-if)#
ip address 10.1.1.1 255.255.255.0
Corp(config-if)#
no shut
----------------------------------------------------------------------------------------------------------------
Corp(config-if)#
int f1/0
Corp(config-if)#
description Switch Port connection to WWW Server
Corp(config-if)#
no shutdown
Corp(config-if)#
int f1/1
Corp(config-if)#
description Switch Port connection to Email Server
Corp(config-if)#
no shutdown
Corp(config-if)#
int f1/2
Corp(config-if)#
description Switch Port connection to DNS Server
Corp(config-if)#
no shutdown
----------------------------------------------------------------------------------------------------------------
Corp(config-if)#
int s0/0/0
Corp(config-if)#
description 1st Connection to R1
Corp(config-if)#
ip address 10.1.2.1 255.255.255.0
Corp(config-if)#
no shut
Corp(config-if)#
int s0/0/1
Corp(config-if)#
description 2nd Connection to R1
Corp(config-if)#
ip address 10.1.3.1 255.255.255.0
Corp(config-if)#
no shut
Corp(config-if)#
int s0/1/0
Corp(config-if)#
description Connection to R2
Corp(config-if)#
ip address 10.1.4.1 255.255.255.0
Corp(config-if)#
no shut
Corp(config-if)#
int fa0/0
Corp(config-if)#
description Connection to R3
Corp(config-if)#
ip address 10.1.5.1 255.255.255.0
Corp(config-if)#
no shut
----------------------------------------------------------------------------------------------------------------
Corp(config-if)#
line con 0
Corp(config-if)#
password console
Corp(config-if)#
login
Corp(config-if)#
logging synchro
Corp(config-if)#
exec-timeout 0 0
----------------------------------------------------------------------------------------------------------------
Corp(config-if)#
line aux 0
Corp(config-if)#
password aux
Corp(config-if)#
login
Corp(config-if)#
exit
----------------------------------------------------------------------------------------------------------------
Corp(config)#
line vty ?
<1-15>Last Line number
Corp(config)#
line vty 0 15
Corp(config-if)#
password telnet
Corp(config-if)#
login
Corp(config-if)#
exit
----------------------------------------------------------------------------------------------------------------
Corp(config)#
no ip domain lookup
Corp(config)#
banner motd # This is my Corp 2811 ISR Router #
Ctrl + Z
%SYS-5-CONFIG_I: Configured from console by console
(Ctrl-Z: When in a config mode, ends the config mode and returns you to privileged EXEC mode.... same as typing exit(?))
Corp#
copy run start
Destination filename [startup-config]?
Building configuration...
[OK]
----------------------------------------------------------------------------------------------------------------
Corp#
show ip int br
Interface IP-Address OK? Method Status Protocol
FastEthernet0/0 10.1.5.1 YES manual up down
FastEthernet0/1 unassigned YES unset administratively down down
Serial0/0/0 10.1.2.1 YES manual down down
Serial0/0/1 10.1.3.1 YES manual down down
Serial0/1/0 10.1.4.1 YES manual down down
Serial0/1/1 unassigned YES unset administratively down down
FastEthernet1/0 unassigned YES unset up up
FastEthernet1/1 unassigned YES unset up up
FastEthernet1/2 unassigned YES unset up up
FastEthernet1/3 unassigned YES unset administratively down down
FastEthernet1/4 unassigned YES unset administratively down down
FastEthernet1/5 unassigned YES unset administratively down down
FastEthernet1/6 unassigned YES unset administratively down down
FastEthernet1/7 unassigned YES unset administratively down down
FastEthernet1/8 unassigned YES unset administratively down down
FastEthernet1/9 unassigned YES unset administratively down down
FastEthernet1/10 unassigned YES unset administratively down down
FastEthernet1/11 unassigned YES unset administratively down down
FastEthernet1/12 unassigned YES unset administratively down down
FastEthernet1/13 unassigned YES unset administratively down down
FastEthernet1/14 unassigned YES unset administratively down down
FastEthernet1/15 unassigned YES unset administratively down down
Vlan1 10.1.1.1 YES manual up up
----------------------------------------------------------------------------------------------------------------
Corp#
show run
Building configuration...
Current configuration : 2073 bytes
!
version 15.1
no service timestamps log datetime msec
no service timestamps debug datetime msec
no service password-encryption
!
hostname Corp
!
!
!
enable secret 5 $1$mERr$V5ujdIM9bTB/I.ipB0gkJ0
!
!
!
!
!
!
no ip cef
no ipv6 cef
!
!
!
!
license udi pid CISCO2811/K9 sn FTX1017U440-
!
!
!
!
!
!
!
!
!
no ip domain-lookup
!
!
spanning-tree mode pvst
!
!
!
!
!
!
interface FastEthernet0/0
description connection to R3
ip address 10.1.5.1 255.255.255.0
duplex auto
speed auto
!
interface FastEthernet0/1
no ip address
duplex auto
speed auto
shutdown
!
interface Serial0/0/0
description 1st connection to R1
ip address 10.1.2.1 255.255.255.0
clock rate 2000000
!
interface Serial0/0/1
description 2nd connection to R1
ip address 10.1.3.1 255.255.255.0
clock rate 2000000
!
interface Serial0/1/0
description connection to R2
ip address 10.1.4.1 255.255.255.0
!
interface Serial0/1/1
no ip address
clock rate 2000000
shutdown
!
interface FastEthernet1/0
description switch port connection to WWW Server
!
interface FastEthernet1/1
description switch port connection to Email Server
!
interface FastEthernet1/2
description switch port connection to DNS Server
!
interface FastEthernet1/3
shutdown
!
interface FastEthernet1/4
shutdown
!
interface FastEthernet1/5
shutdown
!
interface FastEthernet1/6
shutdown
!
interface FastEthernet1/7
shutdown
!
interface FastEthernet1/8
shutdown
!
interface FastEthernet1/9
shutdown
!
interface FastEthernet1/10
shutdown
!
interface FastEthernet1/11
shutdown
!
interface FastEthernet1/12
shutdown
!
interface FastEthernet1/13
shutdown
!
interface FastEthernet1/14
shutdown
!
interface FastEthernet1/15
shutdown
!
interface Vlan1
description Switch Card to Core Network
ip address 10.1.1.1 255.255.255.0
!
ip classless
!
ip flow-export version 9
!
!
!
banner motd ^C This is my Corp 2811 ISR Router ^C
!
!
!
!
!
line con 0
exec-timeout 0 0
password console
logging synchronous
login
!
line aux 0
password aux
login
!
line vty 0 4
password telnet
login
line vty 5 15
password telnet
login
!
!
!
end
-----------------------------------------------------------------------------------------------------------------------
more configurations:
R1
Router(config)#
hostname R1
R1(config)#
enable secret todd
R1(config)#
int s0/0/0
R1(config-if)#
ip address 10.1.2.2 255.255.255.0
R1(config-if)#
Decription 1st connection to corp router
R1(config-if)#
no shut
-----------------------------------------------------------------------------------------------
R1(config-if)#
int s0/0/1
R1(config-if)#
ip address 10.1.3.2 255.255.255.0
R1(config-if)#
Decription 2nd connection to corp router
R1(config-if)#
no shut
-----------------------------------------------------------------------------------------------
R1(config-if)#
int f0/0
R1(config-if)#
ip address 192.168.10.1 255.255.255.0
R1(config-if)#
Decription connection to finance
R1(config-if)#
no shut
-----------------------------------------------------------------------------------------------
R1(config-if)#
int f0/1
R1(config-if)#
ip address 192.168.20.1 255.255.255.0
R1(config-if)#
Decription connection to marketing
R1(config-if)#
no shut
R1(config-if)#
exit
-----------------------------------------------------------------------------------------------
R1(config)#
line con 0
R1(config-line)#
password console
R1(config-line)#
login
R1(config-line)#
logging synchronous
R1(config-line)#
exec-timeout 0 0
-----------------------------------------------------------------------------------------------
R1(config-line)#
line aux 0
R1(config-line)#
password aux
R1(config-line)#
login
R1(config-line)#
exit
-----------------------------------------------------------------------------------------------
R1(config)#
line vty 0 ?
<0-15> Last Line number
R1(config)#
line vty 0 807
R1(config-line)#
password telnet
R1(config-line)#
login
R1(config-line)#
banner motd # This is my R1 Router #
R1(config-line)#
exit
-----------------------------------------------------------------------------------------------
R1(config)#
no ip domain-lookup
R1(config)#
exit
R1#
copy run start
R2
Router(config)#
hostname R2
R2(config)#
enable secret todd
R2(config)#
int s0/0/0
R2(config-if)#
ip address 10.1.4.2 255.255.255.0
R2(config-if)#
description connection to corp router
R2(config-if)#
no shut
-----------------------------------------------------------------------------------------------
R2(config-if)#
int f0/0
R2(config-if)#
ip address 192.168.30.1 255.255.255.0
R2(config-if)#
description connection to sales PC
R2(config-if)#
no shut
-----------------------------------------------------------------------------------------------
R2(config-if)#
int f0/1
R2(config-if)#
ip address 192.168.40.1 255.255.255.0
R2(config-if)#
description connection to HR pc
R2(config-if)#
no shut
-----------------------------------------------------------------------------------------------
R2(config-if)#
line con 0
R2(config-line)#
password console
R2(config-line)#
login
R2(config-line)#
logging synchronous
R2(config-line)#
exec-timeout 0 0
-----------------------------------------------------------------------------------------------
R2(config-line)#
line aux 0
R2(config-line)#
password aux
R2(config-line)#
login
R2(config-line)#
exit
-----------------------------------------------------------------------------------------------
R2(config)#
line vty 0 ?
<0-15> Last Line number
R2(config)#
line vty 0 807
R2(config-line)#
password telnet
R2(config-line)#
login
R2(config-line)#
banner motd # This is my R1 Router #
R2(config-line)#
exit
-----------------------------------------------------------------------------------------------
R2(config)#
no ip domain-lookup
R2(config)#
exit
R2#
copy run start
R3
Router(config)#
hostname R3
R3(config)#
enable secret todd
R3(config)#
int f0/0
R3(config-if)#
ip address 10.1.5.2 255.255.255.0
R3(config-if)#
description connection to corp router
R3(config-if)#
no shut
-----------------------------------------------------------------------------------------------
R3(config-if)#
int dot11radio0/0/0
R3(config-if)#
ip address 172.16.10.1 255.255.255.0
R3(config-if)#
description WLAN for mobile user
R3(config-if)#
no shut
R3(config-if)#
ssid ADMIN
stuck here 2-5-22-- packet tracer isnt taking me into the config-if-ssid prompt
R3(config-if-ssid)#
guest-mode
R3(config-if-ssid)#
authentication open
R3(config-if-ssid)#
ingrastructure-ssid
R3(config-if-ssid)#
exit
-----------------------------------------------------------------------------------------------
R3(config-if)#
line con 0
R3(config-line)#
password console
R3(config-line)#
login
R3(config-line)#
logging synchronous
R3(config-line)#
exec-timeout 0 0
-----------------------------------------------------------------------------------------------
R3(config-line)#
line aux 0
R3(config-line)#
password aux
R3(config-line)#
login
R3(config-line)#
exit
-----------------------------------------------------------------------------------------------
R3(config)#
line vty 0 ?
<0-15> Last Line number
R3(config)#
line vty 0 807
R3(config-line)#
password telnet
R3(config-line)#
login
R3(config-line)#
banner motd # This is my R1 Router #
R3(config-line)#
exit
-----------------------------------------------------------------------------------------------
R3(config)#
no ip domain-lookup
R3(config)#
exit
R3#
copy run start
PROBLEM
i cant get into conf-if-ssid prompt
R3(config-if)#
ssid ADMIN
%LINK-5-CHANGED: Interface Dot11Radio0/0/0, changed state to administratively down
%LINEPROTO-5-UPDOWN: Line protocol on Interface Dot11Radio0/0/0, changed state to down
%LINK-5-CHANGED: Interface Dot11Radio0/0/0, changed state to up
%LINEPROTO-5-UPDOWN: Line protocol on Interface Dot11Radio0/0/0, changed state to up
R3(config-if)#
research led me to this thread, which is a dead end:
further research led me here:
R3(config)# global config mode
R3(config)#
dot11 ssid ADMIN
creates an SSID or lets you config an existing SSID
R3(config-ssid)#
guest-mode
R3(config-ssid)#
%LINK-5-CHANGED: Interface Dot11Radio0/0/0, changed state to administratively down
%LINEPROTO-5-UPDOWN: Line protocol on Interface Dot11Radio0/0/0, changed state to down
%LINK-5-CHANGED: Interface Dot11Radio0/0/0, changed state to up
%LINEPROTO-5-UPDOWN: Line protocol on Interface Dot11Radio0/0/0, changed state to up
R3(config-ssid)#
authentication open
R3(config-ssid)#
%LINK-5-CHANGED: Interface Dot11Radio0/0/0, changed state to administratively down
%LINEPROTO-5-UPDOWN: Line protocol on Interface Dot11Radio0/0/0, changed state to down
%LINK-5-CHANGED: Interface Dot11Radio0/0/0, changed state to up
%LINEPROTO-5-UPDOWN: Line protocol on Interface Dot11Radio0/0/0, changed state to up
R3(config-ssid)#
infrastructure-ssid
R3(config-ssid)#infrastructure-ssid
^
% Invalid input detected at '^' marker.
this command given by the book doesnt appear to be valid
R3(config-ssid)#
?
authentication authentication method
exit Exit from ssid sub mode
guest-mode guest ssid
no Negate a command or set it's defaults
wpa-psk Configure Wi-Fi Protected Access pre-shared key
back into the interface to see what the options are
R3(config-ssid)#
int dot110/0/0
R3(config-if)#
?
arp Set arp type (arpa, probe, snap) or timeout or log options
bandwidth Set bandwidth informational parameter
cdp CDP interface subcommands
crypto Encryption/Decryption commands
delay Specify interface throughput delay
description Interface specific description
encryption Configure dot11 encryption parameters
exit Exit from interface configuration mode
fair-queue Enable Fair Queuing on an Interface
hold-queue Set hold queue depth
ip Interface Internet Protocol config commands
mac-address Manually set interface MAC address
mtu Set the interface Maximum Transmission Unit (MTU)
no Negate a command or set its defaults
priority-group Assign a priority group to an interface
service-policy Configure QoS Service Policy
shutdown Shutdown the selected interface
speed Set allowed radio bit rates
ssid Configure radio service set parameters
tx-ring-limit Configure PA level transmit ring limit
i'll consider the problem *mostly* solved. I was able to assign the SSD.
The infrastructure command may be expendable in this case... to be determined
here is our configuration for R3
R3#
show run
Building configuration...
Current configuration : 1682 bytes
!
version 15.1
no service timestamps log datetime msec
no service timestamps debug datetime msec
no service password-encryption
!
hostname R3
!
!
!
enable secret 5 $1$mERr$V5ujdIM9bTB/I.ipB0gkJ0
!
!
ip dhcp excluded-address 172.16.10.1 172.16.10.10
!
ip dhcp pool Admin
network 172.16.10.0 255.255.255.0
default-router 172.16.10.1
!
dot11 ssid ADMIN
authentication open
guest-mode
!
dot11 ssid ADMIN2
authentication open
guest-mode
!
!
!
ip cef
no ipv6 cef
!
!
!
!
license udi pid CISCO2811/K9 sn FTX1017RE40-
!
!
!
!
!
!
!
!
!
no ip domain-lookup
ip name-server 172.16.10.4
!
!
spanning-tree mode pvst
!
!
!
!
!
!
interface FastEthernet0/0
description connection to corp router
ip address 10.1.5.2 255.255.255.0
duplex auto
speed auto
!
interface FastEthernet0/1
no ip address
duplex auto
speed auto
shutdown
!
interface Dot11Radio0/0/0
description WAN for mobile
ip address 172.16.10.1 255.255.255.0
speed 12.0 18.0 24.0 36.0 48.0 54.0 6.0 9.0 basic-1.0 basic-11.0 basic-2.0 basic-5.5
ssid ADMIN2
!
interface Dot11Radio0/0/1
no ip address
speed 18.0 36.0 48.0 54.0 9.0 basic-12.0 basic-24.0 basic-6.0
!
interface Serial0/1/0
no ip address
clock rate 2000000
!
interface Serial0/1/1
no ip address
clock rate 2000000
!
interface Vlan1
no ip address
shutdown
!
router rip
version 2
network 10.0.0.0
network 172.16.0.0
!
ip classless
ip route 0.0.0.0 0.0.0.0 10.1.5.1
!
ip flow-export version 9
!
!
!
banner motd ^C this is R3 $
this is R3 ^C
!
!
!
!
!
line con 0
exec-timeout 0 0
password console
logging synchronous
login
!
line aux 0
password aux
login
!
line vty 0 4
password telnet
login
line vty 5 15
password telnet
login
!
!
!
end
to summarize...
the book is a little off here.
-----------------------------------------------------------------------------------------------
R3(config-if)#
int dot11radio0/0/0
R3(config-if)#
ip address 172.16.10.1 255.255.255.0
R3(config-if)#
description WLAN for mobile user
R3(config-if)#
no shut
at this point we have created a wireless interface with an IP address but no SSID exists on this router
interface Dot11Radio0/0/0
description test router 2
ip address 172.16.10.1 255.255.255.0
speed 12.0 18.0 24.0 36.0 48.0 54.0 6.0 9.0 basic-1.0 basic-11.0 basic-2.0 basic-5.5
Trying to use the command "ssid ADMIN" doesnt work here. The below commands are invalid here:
R3(config-if)#
ssid ADMIN
R3(config-if-ssid)#
guest-mode
R3(config-if-ssid)#
authentication open
R3(config-if-ssid)#
ingrastructure-ssid
R3(config-if-ssid)#
exit
-----------------------------------------------------------------------------------------------
We need to drop out of config-if, back to config, and enter SSID config mode
-----------------------------------------------------------------------------------------------
R3(config-if)#
exit
R3(config)#
dot11 ssid ADMIN2 creates an ssid named ADMIN2, and puts us into SSID config mode
R3(config-ssid)#
guest-mode
R3(config-ssid)#
authentication open
then out of config-ssid and back to interface config
R3(config-ssid)#
exit
R3(config)
int dot11r0/0/0
R3(config-if)
?
arp Set arp type (arpa, probe, snap) or timeout or log options
bandwidth Set bandwidth informational parameter
cdp CDP interface subcommands
crypto Encryption/Decryption commands
delay Specify interface throughput delay
description Interface specific description
encryption Configure dot11 encryption parameters
exit Exit from interface configuration mode
fair-queue Enable Fair Queuing on an Interface
hold-queue Set hold queue depth
ip Interface Internet Protocol config commands
mac-address Manually set interface MAC address
mtu Set the interface Maximum Transmission Unit (MTU)
no Negate a command or set its defaults
priority-group Assign a priority group to an interface
service-policy Configure QoS Service Policy
shutdown Shutdown the selected interface
speed Set allowed radio bit rates
ssid Configure radio service set parameters
tx-ring-limit Configure PA level transmit ring limit
we have the option for ssid
R3(config-if)
ssid ADMIN2
%LINK-5-CHANGED: Interface Dot11Radio0/0/0, changed state to administratively down
%LINEPROTO-5-UPDOWN: Line protocol on Interface Dot11Radio0/0/0, changed state to down
%LINK-5-CHANGED: Interface Dot11Radio0/0/0, changed state to up
%LINEPROTO-5-UPDOWN: Line protocol on Interface Dot11Radio0/0/0, changed state to up
the router resets the interface..
-----------------------------------------------------------------------------------------------
R3(config-if)
do show run
[cut]
!
!
dot11 ssid ADMIN2
authentication open
guest-mode
!
!
[cut]
!
interface Dot11Radio0/0/0
description test router 2
ip address 172.16.10.1 255.255.255.0
speed 12.0 18.0 24.0 36.0 48.0 54.0 6.0 9.0 basic-1.0 basic-11.0 basic-2.0 basic-5.5
ssid ADMIN2
!
[cut]
the SSID is created and assigned to the interface
To summarize.
Wrong: create the dot11 interface, then create the SSID from CONFIG-IF mode, which puts you into CONFIG-IF-SSID (there is no such mode on this router) mode, then modify the ssid from there...
Correct: create the dot11 interface. Exit CONFIG-IF and go back to GLOBAL CONFIG. Create the SSID which puts you in CONFIG-SSID mode.
Configure the ssid. Then exit CONFIG-SSID. Back into CONFIG-IF, assign the SSID
We have one more task for R3- Configuring the DHCP pool for wireless clients.
R3(config)#
ip dhcp pool Admin creating the pool name as "Admin"
R3(dhcp-config)#
network 172.16.10.0 255.255.255.0
R3(dhcp-config)#
default-router 172.16.10.1 aka default-gateway for clients in the pool
R3(dhcp-config)#
ip name-server 172.16.10.4 dns server
*automatically exits dhcp-config prompt*
R3(config)#
ip dhcp excluded-address 172.16.10.1 172.16.10.10 excludes the range given
172.16.10.1 is the router interface- we need to specifically exclude it from the pool
this setup should allow the wireless client to pick up an IP after connecting to the open SSID.
However, I was having trouble at first-
even though I seemed to have the SSID set correctly, i was hitting a WEP password prompt
i didnt see any obvious issues with the wifi module im using on the laptop:
The Linksys-WPC300N module provides one 2.4GHz wireless interface suitable for connection to wireless networks.
The module supports protocols that use Ethernet for LAN access.
I ended up creating a new SSID, with the same settings as the original:
R3(config)#
dot11 ssid ADMIN2
R3(config-ssid)#
guest-mode
R3(config-ssid)#
authentication open
and then I assigned the ip address to ssid ADMIN2 instead of the orginal ADMIN ssid
R3(config)#
int dot110/0/0
R3(config-if)#
ip address 172.16.10.1 255.255.255.0
R3(config-if)#
description WLAN for mobile user
R3(config-if)#
no shut
R3(config-if)#
ssid ADMIN2
R3#
show run
Building configuration...
Current configuration : 1467 bytes
!
version 15.1
no service timestamps log datetime msec
no service timestamps debug datetime msec
no service password-encryption
!
hostname R3
!
!
!
enable secret 5 $1$mERr$V5ujdIM9bTB/I.ipB0gkJ0
!
!
ip dhcp excluded-address 172.16.10.1 172.16.10.10
!
ip dhcp pool Admin
network 172.16.10.0 255.255.255.0
default-router 172.16.10.1
!
dot11 ssid ADMIN
authentication open
guest-mode
!
dot11 ssid ADMIN2
authentication open
guest-mode
!
!
!
ip cef
no ipv6 cef
!
!
!
!
license udi pid CISCO2811/K9 sn FTX1017RE40-
!
!
!
!
!
!
!
!
!
no ip domain-lookup
ip name-server 172.16.10.4
!
!
spanning-tree mode pvst
!
!
!
!
!
!
interface FastEthernet0/0
description connection to corp router
ip address 10.1.5.2 255.255.255.0
duplex auto
speed auto
!
interface FastEthernet0/1
no ip address
duplex auto
speed auto
shutdown
!
interface Dot11Radio0/0/0
description WAN for mobile
ip address 172.16.10.1 255.255.255.0
speed 12.0 18.0 24.0 36.0 48.0 54.0 6.0 9.0 basic-1.0 basic-11.0 basic-2.0 basic-5.5
ssid ADMIN2
!
interface Dot11Radio0/0/1
no ip address
speed 18.0 36.0 48.0 54.0 9.0 basic-12.0 basic-24.0 basic-6.0
!
interface Vlan1
no ip address
shutdown
!
ip classless
!
ip flow-export version 9
!
!
!
banner motd ^C this is R3 $
this is R3 ^C
!
!
!
!
!
line con 0
exec-timeout 0 0
password console
logging synchronous
login
!
line aux 0
password aux
login
!
line vty 0 4
password telnet
login
line vty 5 15
password telnet
login
!
!
!
end
Recall the DHCP configuration on R3:
R3(config)#
ip dhcp pool Admin creating the pool name as "Admin"
R3(dhcp-config)#
network 172.16.10.0 255.255.255.0
R3(dhcp-config)#
default-router 172.16.10.1 aka default-gateway for clients in the pool
R3(dhcp-config)#
ip name-server 172.16.10.4 dns server
*automatically exits dhcp-config prompt*
R3(config)#
ip dhcp excluded-address 172.16.10.1 172.16.10.10 excludes the range given
172.16.10.1 is the router interface- we need to specifically exclude it from the pool
we can check the configuration:
R3#
show ip dhcp pool
Pool Admin :
Utilization mark (high/low) : 100 / 0
Subnet size (first/next) : 0 / 0
Total addresses : 254
Leased addresses : 1
Excluded addresses : 1
Pending event : none
1 subnet is currently in the pool
Current index IP address range Leased/Excluded/Total
172.16.10.1 172.16.10.1 - 172.16.10.254 1 / 1 / 254
R3#
show ip dhcp binding
IP address Client-ID/ Lease expiration Type
Hardware address
172.16.10.11 00D0.979A.733B -- Automatic
the show command is becoming more familiar
R3#
show ip?
access-lists List access lists
arp IP ARP table
bgp BGP information
cache IP fast-switching route cache
cef Cisco Express Forwarding
dhcp Show items in the DHCP database
eigrp IP-EIGRP show commands
inspect CBAC (Context Based Access Control) information
interface IP interface status and configuration
ips IPS (Intrusion Prevention System) information
nat IP NAT information
nbar Network-Based Application Recognition
ospf OSPF information
protocols IP routing protocol process parameters and statistics
rip IP RIP show commands
route IP routing table
ssh Information on SSH
we'll use show ip route soon on all the routers. For now, here is the output for R3:
R3#
show ip route
Codes: L - local, C - connected, S - static, R - RIP, M - mobile, B - BGP
D - EIGRP, EX - EIGRP external, O - OSPF, IA - OSPF inter area
N1 - OSPF NSSA external type 1, N2 - OSPF NSSA external type 2
E1 - OSPF external type 1, E2 - OSPF external type 2, E - EGP
i - IS-IS, L1 - IS-IS level-1, L2 - IS-IS level-2, ia - IS-IS inter area
* - candidate default, U - per-user static route, o - ODR
P - periodic downloaded static route
Gateway of last resort is not set
10.0.0.0/8 is variably subnetted, 2 subnets, 2 masks
C 10.1.5.0/24 is directly connected, FastEthernet0/0
L 10.1.5.2/32 is directly connected, FastEthernet0/0
172.16.0.0/16 is variably subnetted, 2 subnets, 2 masks
C 172.16.10.0/24 is directly connected, Dot11Radio0/0/0
L 172.16.10.1/32 is directly connected, Dot11Radio0/0/0
Before moving on to the routing configurations, here is a review of the topology
I have switched over to the DrawIO diagram app to lay out the topology.
The Packet Tracer diagram becomes
too crowded to see the labels; it's labeling system forces awkward positioning of the objects; the interface
label's cant be moved, so if objects are too close together their labels cover eachother.. not good.
DrawIO allows a cleaner layout with plenty of room to label interfaces and ip addresses.
As a compromise, I'll use both.
I have the packet tracer objects spread out just enough to see the interfaces
and the label for each router. From here I can jump into the CLI for each device.
The DrawIO diagram allows me to cleary see IP addresses
I want to also review all of the configurations we just performed:
PROBLEM
The book specifies that of the two serial conections between R1 and Corp, there should be a DCE on each end..
Both of my DCE's are on the same end.
First lets be sure we understand what DCE means:
networkengineering.stackexchange.com/
One side of the link (DCE), has to transmit the clock signal, which controls the data rate, and the other side (DTE) receives the clock signal.
That is good enough for now. Note that while the book does specify in the diagram that each side should have a DCE, it was not actually mentioned in the configs.
We did not set a DCE or clock rate when conifguring those interfaces.
To fix this in my Packet Tracer topology, I did some quick research:
While this post wasnt pertaining to Packet Tracer, it got me thinking about the cable itself.
I deleted both of my existing serial connections and looked at the options for creating a new cable.
I noticed one is a DCE and one is a DTE:
Fixed the issue
back to the configuration overview: 4 routers, abbreviated show run output
Corp
interface FastEthernet0/0
description connection to R3
ip address 10.1.5.1 255.255.255.0
duplex auto
speed auto
!
interface FastEthernet0/1
no ip address
duplex auto
speed auto
shutdown
!
interface Serial0/0/0
description 1st connection to R1
ip address 10.1.2.1 255.255.255.0
!
interface Serial0/0/1
description 2nd connection to R1
ip address 10.1.3.1 255.255.255.0
clock rate 2000000
!
interface Serial0/1/0
description connection to R2
ip address 10.1.4.1 255.255.255.0
!
interface Vlan1
description Switch Card to Core Network
ip address 10.1.1.1 255.255.255.0
!
interface FastEthernet1/0
description switch port connection to WWW Server
switchport mode access
switchport nonegotiate
!
interface FastEthernet1/1
description switch port connection to Email Server
switchport mode access
switchport nonegotiate
!
interface FastEthernet1/2
description switch port connection to DNS Server
switchport mode access
switchport nonegotiate
!
R1
interface FastEthernet0/0
description connection to Finance
ip address 192.168.10.1 255.255.255.0
duplex auto
speed auto
!
interface FastEthernet0/1
description connection to Marketing
ip address 192.168.20.1 255.255.255.0
duplex auto
speed auto
!
interface Serial0/0/0
description 1st connection to Corp router
ip address 10.1.2.2 255.255.255.0
clock rate 2000000
!
interface Serial0/0/1
description 2nd connecction to Corp router
ip address 10.1.3.2 255.255.255.0
!
R2
interface FastEthernet0/0
description Connection to Sales PC
ip address 192.168.30.1 255.255.255.0
duplex auto
speed auto
!
interface FastEthernet0/1
description Connection to HR PC
ip address 192.168.40.1 255.255.255.0
duplex auto
speed auto
!
interface Serial0/0/0
description Connection to Corp Router
ip address 10.1.4.2 255.255.255.0
clock rate 2000000
!
interface Serial0/0/1
no ip address
clock rate 2000000
shutdown
!
R3
interface FastEthernet0/0
description connection to corp router
ip address 10.1.5.2 255.255.255.0
duplex auto
speed auto
!
interface FastEthernet0/1
no ip address
duplex auto
speed auto
shutdown
!
interface Dot11Radio0/0/0
description WAN for mobile
ip address 172.16.10.1 255.255.255.0
speed 12.0 18.0 24.0 36.0 48.0 54.0 6.0 9.0 basic-1.0 basic-11.0 basic-2.0 basic-5.5
ssid ADMIN2
and here is the output of show ip route for each router
Codes: C - connected, S - static, I - IGRP, R - RIP, M - mobile, B - BGP
D - EIGRP, EX - EIGRP external, O - OSPF, IA - OSPF inter area
N1 - OSPF NSSA external type 1, N2 - OSPF NSSA external type 2
E1 - OSPF external type 1, E2 - OSPF external type 2, E - EGP
i - IS-IS, L1 - IS-IS level-1, L2 - IS-IS level-2, ia - IS-IS inter area
* - candidate default, U - per-user static route, o - ODR
P - periodic downloaded static route
Gateway of last resort is not set
Corp
10.0.0.0/24 is subnetted, 2 subnets
C 10.1.2.0 is directly connected, Serial0/0/0
C 10.1.3.0 is directly connected, Serial0/0/1
C 192.168.10.0/24 is directly connected, FastEthernet0/0
C 192.168.20.0/24 is directly connected, FastEthernet0/1
R1
10.0.0.0/24 is subnetted, 2 subnets
C 10.1.2.0 is directly connected, Serial0/0/0
C 10.1.3.0 is directly connected, Serial0/0/1
C 192.168.10.0/24 is directly connected, FastEthernet0/0
C 192.168.20.0/24 is directly connected, FastEthernet0/1
R2
10.0.0.0/24 is subnetted, 1 subnets
C 10.1.4.0 is directly connected, Serial0/0/0
C 192.168.30.0/24 is directly connected, FastEthernet0/0
C 192.168.40.0/24 is directly connected, FastEthernet0/1
R3
10.0.0.0/8 is variably subnetted, 2 subnets, 2 masks
C 10.1.5.0/24 is directly connected, FastEthernet0/0
L 10.1.5.2/32 is directly connected, FastEthernet0/0
172.16.0.0/16 is variably subnetted, 2 subnets, 2 masks
C 172.16.10.0/24 is directly connected, Dot11Radio0/0/0
L 172.16.10.1/32 is directly connected, Dot11Radio0/0/0
Note that this is before we have configured any 'routing'. We are seeing configured, directly connected networks.
The output for R3 is particularly interesting
What does 'variably' subnetted mean, and what is the "L" next to these routes. And why do they have a mask of 32?
R3
10.0.0.0/8 is variably subnetted, 2 subnets, 2 masks
C 10.1.5.0/24 is directly connected, FastEthernet0/0
L 10.1.5.2/32 is directly connected, FastEthernet0/0
172.16.0.0/16 is variably subnetted, 2 subnets, 2 masks
C 172.16.10.0/24 is directly connected, Dot11Radio0/0/0
L 172.16.10.1/32 is directly connected, Dot11Radio0/0/0
Cisco forums
That makes sense, but my question is why did the other routing tables not behave the same way? R3 is the only one that shows "L" routes.
The book tells us we're using two different model routers, and indeed they are running different IOS versions:
NOTE that at the time the book was published IOS 15 was not released yet, so the book assumes all routers are running 12.4
But that still doesnt explain why Corp and R3 are behaving differently..
Corp
10.0.0.0/24 is subnetted, 2 subnets
C 10.1.2.0 is directly connected, Serial0/0/0
C 10.1.3.0 is directly connected, Serial0/0/1
C 192.168.10.0/24 is directly connected, FastEthernet0/0
C 192.168.20.0/24 is directly connected, FastEthernet0/1
R1
10.0.0.0/24 is subnetted, 2 subnets
C 10.1.2.0 is directly connected, Serial0/0/0
C 10.1.3.0 is directly connected, Serial0/0/1
C 192.168.10.0/24 is directly connected, FastEthernet0/0
C 192.168.20.0/24 is directly connected, FastEthernet0/1
R2
10.0.0.0/24 is subnetted, 1 subnets
C 10.1.4.0 is directly connected, Serial0/0/0
C 192.168.30.0/24 is directly connected, FastEthernet0/0
C 192.168.40.0/24 is directly connected, FastEthernet0/1
R3
10.0.0.0/8 is variably subnetted, 2 subnets, 2 masks
C 10.1.5.0/24 is directly connected, FastEthernet0/0
L 10.1.5.2/32 is directly connected, FastEthernet0/0
172.16.0.0/16 is variably subnetted, 2 subnets, 2 masks
C 172.16.10.0/24 is directly connected, Dot11Radio0/0/0
L 172.16.10.1/32 is directly connected, Dot11Radio0/0/0
how are Corp and R3 different?
The answer is, they are not...
I have accidentally displayed the R1 output to the Corp windows. Error in translating data from the IOS to this webpage..
here's the corrected output.
Corp
10.0.0.0/8 is variably subnetted, 10 subnets, 2 masks
C 10.1.1.0/24 is directly connected, Vlan1
L 10.1.1.1/32 is directly connected, Vlan1
C 10.1.2.0/24 is directly connected, Serial0/0/0
L 10.1.2.1/32 is directly connected, Serial0/0/0
C 10.1.3.0/24 is directly connected, Serial0/0/1
L 10.1.3.1/32 is directly connected, Serial0/0/1
C 10.1.4.0/24 is directly connected, Serial0/1/0
L 10.1.4.1/32 is directly connected, Serial0/1/0
C 10.1.5.0/24 is directly connected, FastEthernet0/0
L 10.1.5.1/32 is directly connected, FastEthernet0/0
R1
10.0.0.0/24 is subnetted, 2 subnets
C 10.1.2.0 is directly connected, Serial0/0/0
C 10.1.3.0 is directly connected, Serial0/0/1
C 192.168.10.0/24 is directly connected, FastEthernet0/0
C 192.168.20.0/24 is directly connected, FastEthernet0/1
R2
10.0.0.0/24 is subnetted, 1 subnets
C 10.1.4.0 is directly connected, Serial0/0/0
C 192.168.30.0/24 is directly connected, FastEthernet0/0
C 192.168.40.0/24 is directly connected, FastEthernet0/1
R3
10.0.0.0/8 is variably subnetted, 2 subnets, 2 masks
C 10.1.5.0/24 is directly connected, FastEthernet0/0
L 10.1.5.2/32 is directly connected, FastEthernet0/0
172.16.0.0/16 is variably subnetted, 2 subnets, 2 masks
C 172.16.10.0/24 is directly connected, Dot11Radio0/0/0
L 172.16.10.1/32 is directly connected, Dot11Radio0/0/0
We do indeed see consistent behavior differences between IOS versions 12.4 and 15.1
recap Corp and R3 outputs:
update topology with Router versions
That covers the first half of Chapter 8. Now we are ready to configure IP routing on our network.
There are three ways: Static, Default, Dynamic
To set up static routes, we simply need to program the routes using the ip route command
Syntax
ip route
[
destination network
]
[
mask
]
[
next hop
]
[
exitinterface
]
[
administrative distance
]
[
permanent
]
destination network and mask
the network data we're adding to the routing table
next-hop address
the address of the next-hop router that will receive the packet and forward to the remote network.
This is the IP address of a router interface that is directly connected.
It must be pingable.
exit interface
can be used instead of next hop address
administrative distance
by default, static routes have an admin distance of 1 if you use a next hop, or 0 if you use exit interface.
You can change the value by adding an administrative weight at the end of the command. More on this later with dynamic routing.
permanent
if the interface is shut down or the router cant communicate to the next hp router, the route will automatically be discarded from the table by default.
The 'permanent' option keeps the entry in the routing table indefenitely.
-----------------------------------------------------------------------------------------------------
Corp has automatically picked up 5 routes that are directly connected:
10.1.1.0 to corp switch card
10.1.2.0 to R1
10.1.3.0 to R1
10.1.4.0 to R2
10.1.5.0 to R3
We need to program 5 more routes:
192.168.10.0 traverse R1
192.168.20.0 traverse R1
192.168.30.0 traverse R1
192.168.40.0 traverse R2
172.16.10.0 traverse R3
-----------------------------------------------------------------------------------------------------
R1 has automatically picked up 4 routes that are directly connected:
10.1.2.0
10.1.3.0
192.168.10.0
192.168.20.0
We need to program 6 more routes:
10.1.1.0
10.1.4.0
10.1.5.0
192.168.30.0
192.168.40.0
172.16.10.0
-----------------------------------------------------------------------------------------------------
R2 has automatically picked up 3 routes that are directly connected:
10.1.4.0
192.168.30.0
192.168.40.0
We need to program 7 more routes:
10.1.1.0
10.1.2.0
10.1.3.0
10.1.5.0
192.168.10.0
192.168.20.0
172.16.10.0
-----------------------------------------------------------------------------------------------------
R3 has automatically picked up 2 routes that are directly connected:
10.1.5.0
172.16.10.0
We need to program 8 more routes:
10.1.1.0
10.1.2.0
10.1.3.0
10.1.4.0
192.168.10.0
192.168.20.0
192.168.30.0
192.168.40.0
Notice the pattern- each router ends up with 10 routes
There are 10 routes total in this topology. AKA ten broadcast domains
Programming the routes
Corp
Corp(config)#
ip route 192.168.10.0 255.255.255.0 10.1.2.2 150
Corp(config)#
ip route 192.168.20.0 255.255.255.0 10.1.3.2 150
Corp(config)#
ip route 192.168.30.0 255.255.255.0 10.1.4.2 150
Corp(config)#
ip route 192.168.40.0 255.255.255.0 10.1.4.2 150
Corp(config)#
ip route 172.16.10.0 255.255.255.0 10.1.5.2 150
Corp(config)#
do show ip route
In the first line, the router is saying that a
classful A network is being subnetted
There are 5 routes directly connected
We see two lines per route (one for the network and one
for the interface(/32)-
10.0.0.0/8 is variably subnetted, 10 subnets, 2 masks
C 10.1.1.0/24 is directly connected, Vlan1
L 10.1.1.1/32 is directly connected, Vlan1
C 10.1.2.0/24 is directly connected, Serial0/0/0
L 10.1.2.1/32 is directly connected, Serial0/0/0
C 10.1.3.0/24 is directly connected, Serial0/0/1
L 10.1.3.1/32 is directly connected, Serial0/0/1
C 10.1.4.0/24 is directly connected, Serial0/1/0
L 10.1.4.1/32 is directly connected, Serial0/1/0
C 10.1.5.0/24 is directly connected, FastEthernet0/0
L 10.1.5.1/32 is directly connected, FastEthernet0/0
and 5 routes that require traversal of a router to reach
172.16.0.0/24 is subnetted, 1 subnets
S 172.16.10.0/24 [150/0] via 10.1.5.2
S 192.168.10.0/24 [150/0] via 10.1.2.2
S 192.168.20.0/24 [150/0] via 10.1.3.2
S 192.168.30.0/24 [150/0] via 10.1.4.2
S 192.168.40.0/24 [150/0] via 10.1.4.2
R1
R1(config)#
ip route 10.1.1.0 255.255.255.0 10.1.2.1 150
R1(config)#
ip route 10.1.4.0 255.255.255.0 10.1.3.1 150
R1(config)#
ip route 10.1.5.0 255.255.255.0 10.1.2.1 150
R1(config)#
ip route 192.168.30.0 255.255.255.0 10.1.3.1 150
R1(config)#
ip route 192.168.40.0 255.255.255.0 10.1.2.1 150
R1(config)#
ip route 172.16.10.0 255.255.255.0 10.1.3.1 150
the only way to get across the corp router is to go into it via 10.1.2.1 or 10.1.3.1
R1(config)#
do show ip route
10.0.0.0/24 is subnetted, 5 subnets
S 10.1.1.0 [150/0] via 10.1.2.1
C 10.1.2.0 is directly connected, Serial0/0/0
C 10.1.3.0 is directly connected, Serial0/0/1
S 10.1.4.0 [150/0] via 10.1.3.1
S 10.1.5.0 [150/0] via 10.1.2.1
172.16.0.0/24 is subnetted, 1 subnets
S 172.16.10.0 [150/0] via 10.1.3.1
C 192.168.10.0/24 is directly connected, FastEthernet0/0
C 192.168.20.0/24 is directly connected, FastEthernet0/1
S 192.168.30.0/24 [150/0] via 10.1.3.1
S 192.168.40.0/24 [150/0] via 10.1.2.1
R2
R2(config)#
iproute 10.1.1.0 255.255.255.0 10.1.4.1 150
R2(config)#
iproute 10.1.2.0 255.255.255.0 10.1.4.1 150
R2(config)#
iproute 10.1.3.0 255.255.255.0 10.1.4.1 150
R2(config)#
iproute 10.1.5.0 255.255.255.0 10.1.4.1 150
R2(config)#
iproute 192.168.10.0 255.255.255.0 10.1.4.1 150
R2(config)#
iproute 192.168.20.0 255.255.255.0 10.1.4.1 150
the only way to get across Corp is to go into it via 10.1.4.1
R2(config)#
do show ip route
10.0.0.0/24 is subnetted, 5 subnets
S 10.1.1.0 [150/0] via 10.1.4.1
S 10.1.2.0 [150/0] via 10.1.4.1
S 10.1.3.0 [150/0] via 10.1.4.1
C 10.1.4.0 is directly connected, Serial0/0/0
S 10.1.5.0 [150/0] via 10.1.4.1
172.16.0.0/24 is subnetted, 1 subnets
S 172.16.10.0 [150/0] via 10.1.4.1
S 192.168.10.0/24 [150/0] via 10.1.4.1
S 192.168.20.0/24 [150/0] via 10.1.4.1
C 192.168.30.0/24 is directly connected, FastEthernet0/0
C 192.168.40.0/24 is directly connected, FastEthernet0/1
R3
R3(config)#
ip route 10.1.1.0 255.255.255.0 fastethernet 0/0 150
R3(config)#
ip route 10.1.2.0 255.255.255.0 fastethernet 0/0 150
R3(config)#
ip route 10.1.3.0 255.255.255.0 fastethernet 0/0 150
R3(config)#
ip route 10.1.4.0 255.255.255.0 fastethernet 0/0 150
R3(config)#
ip route 192.168.10.0 255.255.255.0 fastethernet 0/0 150
R3(config)#
ip route 192.168.20.0 255.255.255.0 fastethernet 0/0 150
R3(config)#
ip route 192.168.30.0 255.255.255.0 fastethernet 0/0 150
R3(config)#
ip route 192.168.40.0 255.255.255.0 fastethernet 0/0 150
the only way to get across Corp is to EXIT R3 via F0/0
R3(config)#
do show ip route
10.0.0.0/8 is variably subnetted, 6 subnets, 2 masks
S 10.1.1.0/24 is directly connected, FastEthernet0/0
S 10.1.2.0/24 is directly connected, FastEthernet0/0
S 10.1.3.0/24 is directly connected, FastEthernet0/0
S 10.1.4.0/24 is directly connected, FastEthernet0/0
C 10.1.5.0/24 is directly connected, FastEthernet0/0
L 10.1.5.2/32 is directly connected, FastEthernet0/0
172.16.0.0/16 is variably subnetted, 2 subnets, 2 masks
C 172.16.10.0/24 is directly connected, Dot11Radio0/0/0
L 172.16.10.1/32 is directly connected, Dot11Radio0/0/0
S 192.168.10.0/24 is directly connected, FastEthernet0/0
S 192.168.20.0/24 is directly connected, FastEthernet0/0
S 192.168.30.0/24 is directly connected, FastEthernet0/0
S 192.168.40.0/24 is directly connected, FastEthernet0/0
before verifying connectivity across the network, we need to make sure all of our hosts are set. The book is giving us the IP addresses for the servers:
Server Gateway 10.1.1.1
ServerWeb 10.1.1.2
ServerEmail 10.1.1.3
ServerDNS 10.1.1.4
Now we can do some testing across the network:
R3#
ping 10.1.2.2
traverse Corp to R1
R3#
ping 10.1.1.1
traverse Corp to a Corp interface we arent directly connected to
R3#
ping 10.1.1.2
traverse Corp to Web server
R3#
ping 10.1.1.3
traverse Corp to Email server
R3#
ping 10.1.1.4
traverse Corp to DNS server
MobileUser
ping 192.168.10.2
traverse R3, Corp, R1 to Finance client
MobileUser
tracert 192.168.10.2
traverse R3, Corp, R1 to Finance client
Tracing route to 192.168.10.2 over a maximum of 30 hops:
1 19 ms 5 ms 20 ms 172.16.10.1
2 20 ms 6 ms 11 ms 10.1.5.1
3 11 ms 15 ms 10 ms 10.1.3.2
4 9 ms 13 ms 22 ms 192.168.10.2
Trace complete.
notice how the trace doesnt count an egress as a hop, only an ingress
ALSO NOTE that tracert is a Windows command.
the IOS equivalent is traceroute
notice how the output differs from the Windows command
R3
traceroute 192.168.10.2
Type escape sequence to abort.
Tracing the route to 192.168.10.2
1 10.1.5.1 0 msec 0 msec 0 msec
2 10.1.2.2 6 msec 0 msec 5 msec
3 192.168.10.2 1 msec 4 msec 3 msec
Default Routing
we could have done this on R3
R3(config)#
ip route 0.0.0.0 0.0.0.0 10.1.5.1
as an alternative to this configuration on R3
R3(config)#
ip route 10.1.1.0 255.255.255.0 fastethernet 0/0 150
R3(config)#
ip route 10.1.2.0 255.255.255.0 fastethernet 0/0 150
R3(config)#
ip route 10.1.3.0 255.255.255.0 fastethernet 0/0 150
R3(config)#
ip route 10.1.4.0 255.255.255.0 fastethernet 0/0 150
R3(config)#
ip route 192.168.10.0 255.255.255.0 fastethernet 0/0 150
R3(config)#
ip route 192.168.20.0 255.255.255.0 fastethernet 0/0 150
R3(config)#
ip route 192.168.30.0 255.255.255.0 fastethernet 0/0 150
R3(config)#
ip route 192.168.40.0 255.255.255.0 fastethernet 0/0 150
the only way to get across Corp is to EXIT R3 via F0/0
This is called default routing. It should only be used on 'stub routers'- those with only one exit path out of the network.
if you try to put a default route on a non-stub router, you could create loops, since there will be more than one path to other routers...
Think of a default route as a static route that uses a wildcard address and mask. The wildcard is 0.0.0.0
to further analyze this comparison, I'm going to remove the routes from R3...
R3(config)#
no ip route 10.1.1.0 255.255.255.0 fastethernet0/0 150
R3(config)#
no ip route 10.1.2.0 255.255.255.0 fastethernet0/0 150
R3(config)#
no ip route 10.1.3.0 255.255.255.0 fastethernet0/0 150
R3(config)#
no ip route 10.1.4.0 255.255.255.0 fastethernet0/0 150
R3(config)#
no ip route 192.168.10.0 255.255.255.0 fastethernet0/0 150
R3(config)#
no ip route 192.168.20.0 255.255.255.0 fastethernet0/0 150
R3(config)#
no ip route 192.168.30.0 255.255.255.0 fastethernet0/0 150
R3(config)#
no ip route 192.168.40.0 255.255.255.0 fastethernet0/0 150
and then set the default route instead.
R3#
ip route 0.0.0.0 0.0.0.0 10.1.5.1 --- ingress at next hop
OR
R3#
ip route 0.0.0.0 0.0.0.0 Fa0/0 --- egress interface
Then compare the output of show ip route
static routes set
R3#
show ip route
Gateway of last resort is not set
10.0.0.0/8 is variably subnetted, 6 subnets, 2 masks
S 10.1.1.0/24 is directly connected, FastEthernet0/0
S 10.1.2.0/24 is directly connected, FastEthernet0/0
S 10.1.3.0/24 is directly connected, FastEthernet0/0
S 10.1.4.0/24 is directly connected, FastEthernet0/0
C 10.1.5.0/24 is directly connected, FastEthernet0/0
L 10.1.5.2/32 is directly connected, FastEthernet0/0
172.16.0.0/16 is variably subnetted, 2 subnets, 2 masks
C 172.16.10.0/24 is directly connected, Dot11Radio0/0/0
L 172.16.10.1/32 is directly connected, Dot11Radio0/0/0
S 192.168.10.0/24 is directly connected, FastEthernet0/0
S 192.168.20.0/24 is directly connected, FastEthernet0/0
S 192.168.30.0/24 is directly connected, FastEthernet0/0
S 192.168.40.0/24 is directly connected, FastEthernet0/0
default route set
R3#
show ip route
Gateway of last resort is 10.1.5.1 to network 0.0.0.0
10.0.0.0/8 is variably subnetted, 2 subnets, 2 masks
C 10.1.5.0/24 is directly connected, FastEthernet0/0
L 10.1.5.2/32 is directly connected, FastEthernet0/0
172.16.0.0/16 is variably subnetted, 2 subnets, 2 masks
C 172.16.10.0/24 is directly connected, Dot11Radio0/0/0
L 172.16.10.1/32 is directly connected, Dot11Radio0/0/0
S* 0.0.0.0/0 [1/0] via 10.1.5.1
two directly connected networks- 10.1.5.0 and 172.16.10.0
anything not included in those networks goes to ingress of attached neighbor Corp 10.1.5.1
in this toplogy, that includes:
192.168.10.0
192.168.20.0
192.168.30.0
192.168.40.0
and
10.1.1.0
10.1.2.0
10.1.3.0
10.1.4.0
RIP Routing Information Protocol
R1(config)#
router ?
bgp Border Gateway Protocol (BGP)
eigrp Enhanced Interior Gateway Routing Protocol (EIGRP)
ospf Open Shortest Path First (OSPF)
rip Routing Information Protocol (RIP)
set RIP on Corp
Corp(config)#
router rip
Corp(config-router)#
network 10.0.0.0
set RIP on R1
R1(config)#
router rip
R1(config-router)#
network 10.0.0.0
R1 routing table
R1(config)#
do show ip route
10.0.0.0/24 is subnetted, 5 subnets
R 10.1.1.0 [120/1] via 10.1.2.1, 00:00:21, Serial0/0/0
[120/1] via 10.1.3.1, 00:00:21, Serial0/0/1
C 10.1.2.0 is directly connected, Serial0/0/0
C 10.1.3.0 is directly connected, Serial0/0/1
R 10.1.4.0 [120/1] via 10.1.2.1, 00:00:21, Serial0/0/0
[120/1] via 10.1.3.1, 00:00:21, Serial0/0/1
R 10.1.5.0 [120/1] via 10.1.2.1, 00:00:21, Serial0/0/0
[120/1] via 10.1.3.1, 00:00:21, Serial0/0/1
172.16.0.0/24 is subnetted, 1 subnets
S 172.16.10.0 [150/0] via 10.1.3.1
C 192.168.10.0/24 is directly connected, FastEthernet0/0
C 192.168.20.0/24 is directly connected, FastEthernet0/1
S 192.168.30.0/24 [150/0] via 10.1.3.1
S 192.168.40.0/24 [150/0] via 10.1.2.1
here's R1 before RIP, with only static routes set:
R1(config)#
do show ip route
10.0.0.0/24 is subnetted, 5 subnets
S 10.1.1.0 [150/0] via 10.1.2.1
C 10.1.2.0 is directly connected, Serial0/0/0
C 10.1.3.0 is directly connected, Serial0/0/1
S 10.1.4.0 [150/0] via 10.1.3.1
S 10.1.5.0 [150/0] via 10.1.2.1
172.16.0.0/24 is subnetted, 1 subnets
S 172.16.10.0 [150/0] via 10.1.3.1
C 192.168.10.0/24 is directly connected, FastEthernet0/0
C 192.168.20.0/24 is directly connected, FastEthernet0/1
S 192.168.30.0/24 [150/0] via 10.1.3.1
S 192.168.40.0/24 [150/0] via 10.1.2.1
These RIP routes are being advertised as available *to other RIP routers*.
CORP is advertisting THREE routes via RIP to R1 right now
10.1.1.0
10.1.4.0
10.1.5.0
access to those networks can be achieved by R1 by going THROUGH CORP via ingress .2.1 or .3.1
The advantage..... is that we didnt statically program these routes
we engaged RIP, on BOTH routers- R1 and Corp, and handed them BOTH the network "10.0.0.0"
So, why did RIP choose to display these particular routes
Keep in mind that the output above is from R1 only... In the context of the R1 ROUTER ONLY,
there are three relevant routes within the "10.0.0.0" parameter we specified. The three routes involve Corp.
Corp is sending RIP data about these routes to Corp.
Lets look closer at how this is happening:
here's our starting point before any RIP is set
here's our routing tables after i set RIP with 10.0.0.0 on both..
FIRST i set it on Corp, then R1.(per the book's instructions) As a result we are seeing RIP routes in R1 only....
then I went back to a fresh packet tracer file with no RIP set. And I set RIP in the opposite order;
FIRST i set it on R1, then Corp. And again, we are seeing RIP routes in R1 only....
I wanted to prove that it didnt matter which order we enabled RIP on the two routers. What matters here is that
we enable RIP on both of them with the criteria of 10.0.0.0
Recall the topology:
if Corp and R1 are set for RIP and given the criteria 10.0.0.0, meaning that we are trying to reach networks
within that range, then it follows that Corp will advertise 1.1.0, 1.4.0, and 1.5.0 to R1, because Corp stands between those networks
and R1
"Hi R1, I'm Corp I have three networks that fall inside 10.0.0.0, and you can reach them through me via .2.1 or .3.1"
It also follows that Corp's routing table shows no RIP routes- because R1 isnt advertising any. R1 doesnt have any networks
in the 10.0.0.0 range that Corp could reach
To further clarify this, we'll proceed with the book's instructions. We'll now set more RIP routes on R1
R1(config)#
router rip
R1(config-router)#
network 192.168.10.0
R1(config-router)#
network 192.168.20.0
Corp routing table before RIP set on R1:
Corp#
show ip route
10.0.0.0/8 is variably subnetted, 10 subnets, 2 masks
C 10.1.1.0/24 is directly connected, Vlan1
L 10.1.1.1/32 is directly connected, Vlan1
C 10.1.2.0/24 is directly connected, Serial0/0/0
L 10.1.2.1/32 is directly connected, Serial0/0/0
C 10.1.3.0/24 is directly connected, Serial0/0/1
L 10.1.3.1/32 is directly connected, Serial0/0/1
C 10.1.4.0/24 is directly connected, Serial0/1/0
L 10.1.4.1/32 is directly connected, Serial0/1/0
C 10.1.5.0/24 is directly connected, FastEthernet0/0
L 10.1.5.1/32 is directly connected, FastEthernet0/0
172.16.0.0/24 is subnetted, 1 subnets
S 172.16.10.0/24 [150/0] via 10.1.5.2
S 192.168.10.0/24 [150/0] via 10.1.2.2
S 192.168.20.0/24 [150/0] via 10.1.3.2
S 192.168.30.0/24 [150/0] via 10.1.4.2
S 192.168.40.0/24 [150/0] via 10.1.4.2
Corp routing table after RIP set on R1:
Gateway of last resort is not set
10.0.0.0/8 is variably subnetted, 10 subnets, 2 masks
C 10.1.1.0/24 is directly connected, Vlan1
L 10.1.1.1/32 is directly connected, Vlan1
C 10.1.2.0/24 is directly connected, Serial0/0/0
L 10.1.2.1/32 is directly connected, Serial0/0/0
C 10.1.3.0/24 is directly connected, Serial0/0/1
L 10.1.3.1/32 is directly connected, Serial0/0/1
C 10.1.4.0/24 is directly connected, Serial0/1/0
L 10.1.4.1/32 is directly connected, Serial0/1/0
C 10.1.5.0/24 is directly connected, FastEthernet0/0
L 10.1.5.1/32 is directly connected, FastEthernet0/0
nothing changed so far
172.16.0.0/24 is subnetted, 1 subnets
S 172.16.10.0/24 [150/0] via 10.1.5.2
no change
R 192.168.10.0/24 [120/1] via 10.1.2.2, 00:00:08, Serial0/0/0
[120/1] via 10.1.3.2, 00:00:08, Serial0/0/1
RIP overrides static- 2 paths available now
R 192.168.20.0/24 [120/1] via 10.1.2.2, 00:00:08, Serial0/0/0
[120/1] via 10.1.3.2, 00:00:08, Serial0/0/1
RIP overrides static- 2 paths available now
S 192.168.30.0/24 [150/0] via 10.1.4.2
no change
S 192.168.40.0/24 [150/0] via 10.1.4.2
no change
"Hi Corp- I'm R1 and I have zero networks
that fall inside 10.0.0.0, however I do have some networks that fall within
192.168.20.0 and 192.168.10.0
and you can reach them through me(R1) if you ingress at .1.2.2 or .1.3.2"
ok, we have the concept down. Time to proceed and set up RIP on R2............
R2(config)#
router rip
R2(config-router)#
network 10.0.0.0
R2(config-router)#
network 192.168.30.0
R2(config-router)#
network 192.168.40.0
R2 before RIP enabled
R2#
show ip route
10.0.0.0/24 is subnetted, 5 subnets
S 10.1.1.0 [150/0] via 10.1.4.1
S 10.1.2.0 [150/0] via 10.1.4.1
S 10.1.3.0 [150/0] via 10.1.4.1
C 10.1.4.0 is directly connected, Serial0/0/0
S 10.1.5.0 [150/0] via 10.1.4.1
172.16.0.0/24 is subnetted, 1 subnets
S 172.16.10.0 [150/0] via 10.1.4.1
S 192.168.10.0/24 [150/0] via 10.1.4.1
S 192.168.20.0/24 [150/0] via 10.1.4.1
C 192.168.30.0/24 is directly connected, FastEthernet0/0
C 192.168.40.0/24 is directly connected, FastEthernet0/1
R2 after RIP added
R2#
show ip route
10.0.0.0/24 is subnetted, 5 subnets
R 10.1.1.0 [120/1] via 10.1.4.1, 00:00:24, Serial0/0/0
from corp
R 10.1.2.0 [120/1] via 10.1.4.1, 00:00:24, Serial0/0/0
from corp
R 10.1.3.0 [120/1] via 10.1.4.1, 00:00:24, Serial0/0/0
from corp
C 10.1.4.0 is directly connected, Serial0/0/0
R 10.1.5.0 [120/1] via 10.1.4.1, 00:00:24, Serial0/0/0
from corp
172.16.0.0/24 is subnetted, 1 subnets
S 172.16.10.0 [150/0] via 10.1.4.1
R 192.168.10.0/24 [120/2] via 10.1.4.1, 00:00:24, Serial0/0/0
from R1 via corp
R 192.168.20.0/24 [120/2] via 10.1.4.1, 00:00:24, Serial0/0/0
from R1 via corp
C 192.168.30.0/24 is directly connected, FastEthernet0/0
C 192.168.40.0/24 is directly connected, FastEthernet0/1
now lets compare the Corp and R1 routing tables- before RIP was set on R2 and after
Corp before R2 RIP
Corp#
show ip route
10.0.0.0/8 is variably subnetted, 10 subnets, 2 masks
C 10.1.1.0/24 is directly connected, Vlan1
L 10.1.1.1/32 is directly connected, Vlan1
C 10.1.2.0/24 is directly connected, Serial0/0/0
L 10.1.2.1/32 is directly connected, Serial0/0/0
C 10.1.3.0/24 is directly connected, Serial0/0/1
L 10.1.3.1/32 is directly connected, Serial0/0/1
C 10.1.4.0/24 is directly connected, Serial0/1/0
L 10.1.4.1/32 is directly connected, Serial0/1/0
C 10.1.5.0/24 is directly connected, FastEthernet0/0
L 10.1.5.1/32 is directly connected, FastEthernet0/0
172.16.0.0/24 is subnetted, 1 subnets
S 172.16.10.0/24 [150/0] via 10.1.5.2
R 192.168.10.0/24 [120/1] via 10.1.2.2, 00:00:02, Serial0/0/0
[120/1] via 10.1.3.2, 00:00:02, Serial0/0/1
R 192.168.20.0/24 [120/1] via 10.1.2.2, 00:00:02, Serial0/0/0
[120/1] via 10.1.3.2, 00:00:02, Serial0/0/1
from R1
S 192.168.30.0/24 [150/0] via 10.1.4.2
S 192.168.40.0/24 [150/0] via 10.1.4.2
Corp after R2 RIP
Corp#
show ip route
10.0.0.0/8 is variably subnetted, 10 subnets, 2 masks
C 10.1.1.0/24 is directly connected, Vlan1
L 10.1.1.1/32 is directly connected, Vlan1
C 10.1.2.0/24 is directly connected, Serial0/0/0
L 10.1.2.1/32 is directly connected, Serial0/0/0
C 10.1.3.0/24 is directly connected, Serial0/0/1
L 10.1.3.1/32 is directly connected, Serial0/0/1
C 10.1.4.0/24 is directly connected, Serial0/1/0
L 10.1.4.1/32 is directly connected, Serial0/1/0
C 10.1.5.0/24 is directly connected, FastEthernet0/0
L 10.1.5.1/32 is directly connected, FastEthernet0/0
172.16.0.0/24 is subnetted, 1 subnets
S 172.16.10.0/24 [150/0] via 10.1.5.2
R 192.168.10.0/24 [120/1] via 10.1.2.2, 00:00:19, Serial0/0/0
[120/1] via 10.1.3.2, 00:00:19, Serial0/0/1
R 192.168.20.0/24 [120/1] via 10.1.2.2, 00:00:19, Serial0/0/0
[120/1] via 10.1.3.2, 00:00:19, Serial0/0/1
from R1
R 192.168.30.0/24 [120/1] via 10.1.4.2, 00:00:15, Serial0/1/0
R 192.168.40.0/24 [120/1] via 10.1.4.2, 00:00:15, Serial0/1/0
from R2
RIP on R2 is advertising .30.0 and .40.0 to Corp
R1 before R2 RIP
R1#
show ip route
10.0.0.0/24 is subnetted, 5 subnets
R 10.1.1.0 [120/1] via 10.1.2.1, 00:00:05, Serial0/0/0
[120/1] via 10.1.3.1, 00:00:05, Serial0/0/1
from Corp
C 10.1.2.0 is directly connected, Serial0/0/0
C 10.1.3.0 is directly connected, Serial0/0/1
R 10.1.4.0 [120/1] via 10.1.2.1, 00:00:05, Serial0/0/0
[120/1] via 10.1.3.1, 00:00:05, Serial0/0/1
R 10.1.5.0 [120/1] via 10.1.2.1, 00:00:05, Serial0/0/0
[120/1] via 10.1.3.1, 00:00:05, Serial0/0/1
from Corp
172.16.0.0/24 is subnetted, 1 subnets
S 172.16.10.0 [150/0] via 10.1.3.1
C 192.168.10.0/24 is directly connected, FastEthernet0/0
C 192.168.20.0/24 is directly connected, FastEthernet0/1
S 192.168.30.0/24 [150/0] via 10.1.3.1
S 192.168.40.0/24 [150/0] via 10.1.2.1
R1 after R2 RIP
R1#
show ip route
10.0.0.0/24 is subnetted, 5 subnets
R 10.1.1.0 [120/1] via 10.1.2.1, 00:00:06, Serial0/0/0
[120/1] via 10.1.3.1, 00:00:06, Serial0/0/1
from Corp
C 10.1.2.0 is directly connected, Serial0/0/0
C 10.1.3.0 is directly connected, Serial0/0/1
R 10.1.4.0 [120/1] via 10.1.2.1, 00:00:06, Serial0/0/0
[120/1] via 10.1.3.1, 00:00:06, Serial0/0/1
R 10.1.5.0 [120/1] via 10.1.2.1, 00:00:06, Serial0/0/0
[120/1] via 10.1.3.1, 00:00:06, Serial0/0/1
from Corp
172.16.0.0/24 is subnetted, 1 subnets
S 172.16.10.0 [150/0] via 10.1.3.1
C 192.168.10.0/24 is directly connected, FastEthernet0/0
C 192.168.20.0/24 is directly connected, FastEthernet0/1
R 192.168.30.0/24 [120/2] via 10.1.3.1, 00:00:06, Serial0/0/1
[120/2] via 10.1.2.1, 00:00:06, Serial0/0/0
R 192.168.40.0/24 [120/2] via 10.1.2.1, 00:00:06, Serial0/0/0
[120/2] via 10.1.3.1, 00:00:06, Serial0/0/1
from R2 via Corp
Now to set RIP on R3
R3(config)#
router rip
R3(config-router)#
network 10.0.0.0
R3(config-router)#
network 172.16.0.0
note that R3 is our only router with "gateway of last resort" set because we set a default route instead of static routes
As a result, we only see directly connected routes listed, along with a single "S*" for the default gateway
R3 before RIP
R3#
show ip route
Gateway of last resort is 10.1.5.1 to network 0.0.0.0
10.0.0.0/8 is variably subnetted, 2 subnets, 2 masks
C 10.1.5.0/24 is directly connected, FastEthernet0/0
L 10.1.5.2/32 is directly connected, FastEthernet0/0
172.16.0.0/16 is variably subnetted, 2 subnets, 2 masks
C 172.16.10.0/24 is directly connected, Dot11Radio0/0/0
L 172.16.10.1/32 is directly connected, Dot11Radio0/0/0
S* 0.0.0.0/0 [1/0] via 10.1.5.1
R3 after RIP
R3#
show ip route
Gateway of last resort is 10.1.5.1 to network 0.0.0.0
-------------------------------------------------------------
10.0.0.0/8 is variably subnetted, 6 subnets, 2 masks
R 10.1.1.0/24 [120/1] via 10.1.5.1, 00:00:21, FastEthernet0/0
R 10.1.2.0/24 [120/1] via 10.1.5.1, 00:00:21, FastEthernet0/0
R 10.1.3.0/24 [120/1] via 10.1.5.1, 00:00:21, FastEthernet0/0
R 10.1.4.0/24 [120/1] via 10.1.5.1, 00:00:21, FastEthernet0/0
from Corp
C 10.1.5.0/24 is directly connected, FastEthernet0/0
L 10.1.5.2/32 is directly connected, FastEthernet0/0
-------------------------------------------------------------
172.16.0.0/16 is variably subnetted, 2 subnets, 2 masks
C 172.16.10.0/24 is directly connected, Dot11Radio0/0/0
L 172.16.10.1/32 is directly connected, Dot11Radio0/0/0
R 192.168.10.0/24 [120/2] via 10.1.5.1, 00:00:21, FastEthernet0/0
R 192.168.20.0/24 [120/2] via 10.1.5.1, 00:00:21, FastEthernet0/0
From R1 via Corp
R 192.168.30.0/24 [120/2] via 10.1.5.1, 00:00:21, FastEthernet0/0
R 192.168.40.0/24 [120/2] via 10.1.5.1, 00:00:21, FastEthernet0/0
From R2 via Corp
S* 0.0.0.0/0 [1/0] via 10.1.5.1
Corp before R3 RIP
Corp#
show ip route
10.0.0.0/8 is variably subnetted, 10 subnets, 2 masks
C 10.1.1.0/24 is directly connected, Vlan1
L 10.1.1.1/32 is directly connected, Vlan1
C 10.1.2.0/24 is directly connected, Serial0/0/0
L 10.1.2.1/32 is directly connected, Serial0/0/0
C 10.1.3.0/24 is directly connected, Serial0/0/1
L 10.1.3.1/32 is directly connected, Serial0/0/1
C 10.1.4.0/24 is directly connected, Serial0/1/0
L 10.1.4.1/32 is directly connected, Serial0/1/0
C 10.1.5.0/24 is directly connected, FastEthernet0/0
L 10.1.5.1/32 is directly connected, FastEthernet0/0
172.16.0.0/24 is subnetted, 1 subnets
S 172.16.10.0/24 [150/0] via 10.1.5.2
R 192.168.10.0/24 [120/1] via 10.1.2.2, 00:00:26, Serial0/0/0
[120/1] via 10.1.3.2, 00:00:26, Serial0/0/1
R 192.168.20.0/24 [120/1] via 10.1.2.2, 00:00:26, Serial0/0/0
[120/1] via 10.1.3.2, 00:00:26, Serial0/0/1
from R1 via corp
R 192.168.30.0/24 [120/1] via 10.1.4.2, 00:00:21, Serial0/1/0
R 192.168.40.0/24 [120/1] via 10.1.4.2, 00:00:21, Serial0/1/0
from R2 via corp
Corp after R3 RIP
Corp#
show ip route
10.0.0.0/8 is variably subnetted, 10 subnets, 2 masks
C 10.1.1.0/24 is directly connected, Vlan1
L 10.1.1.1/32 is directly connected, Vlan1
C 10.1.2.0/24 is directly connected, Serial0/0/0
L 10.1.2.1/32 is directly connected, Serial0/0/0
C 10.1.3.0/24 is directly connected, Serial0/0/1
L 10.1.3.1/32 is directly connected, Serial0/0/1
C 10.1.4.0/24 is directly connected, Serial0/1/0
L 10.1.4.1/32 is directly connected, Serial0/1/0
C 10.1.5.0/24 is directly connected, FastEthernet0/0
L 10.1.5.1/32 is directly connected, FastEthernet0/0
172.16.0.0/16 is variably subnetted, 2 subnets, 2 masks
R 172.16.0.0/16 [120/1] via 10.1.5.2, 00:00:13, FastEthernet0/0
S 172.16.10.0/24 [150/0] via 10.1.5.2
from R3
R 192.168.10.0/24 [120/1] via 10.1.3.2, 00:00:13, Serial0/0/1
[120/1] via 10.1.2.2, 00:00:13, Serial0/0/0
R 192.168.20.0/24 [120/1] via 10.1.3.2, 00:00:13, Serial0/0/1
[120/1] via 10.1.2.2, 00:00:13, Serial0/0/0
from R1 via corp
R 192.168.30.0/24 [120/1] via 10.1.4.2, 00:00:24, Serial0/1/0
R 192.168.40.0/24 [120/1] via 10.1.4.2, 00:00:24, Serial0/1/0
from R2 via corp
R2 before R3 RIP
R2#
show ip route
10.0.0.0/24 is subnetted, 5 subnets
R 10.1.1.0 [120/1] via 10.1.4.1, 00:00:15, Serial0/0/0
R 10.1.2.0 [120/1] via 10.1.4.1, 00:00:15, Serial0/0/0
R 10.1.3.0 [120/1] via 10.1.4.1, 00:00:15, Serial0/0/0
from Corp
C 10.1.4.0 is directly connected, Serial0/0/0
R 10.1.5.0 [120/1] via 10.1.4.1, 00:00:15, Serial0/0/0
from Corp
172.16.0.0/24 is subnetted, 1 subnets
S 172.16.10.0 [150/0] via 10.1.4.1
R 192.168.10.0/24 [120/2] via 10.1.4.1, 00:00:15, Serial0/0/0
R 192.168.20.0/24 [120/2] via 10.1.4.1, 00:00:15, Serial0/0/0
from R1 via Corp
C 192.168.30.0/24 is directly connected, FastEthernet0/0
C 192.168.40.0/24 is directly connected, FastEthernet0/1
R2 after R3 RIP
R2#
show ip route
10.0.0.0/24 is subnetted, 5 subnets
R 10.1.1.0 [120/1] via 10.1.4.1, 00:00:20, Serial0/0/0
R 10.1.2.0 [120/1] via 10.1.4.1, 00:00:20, Serial0/0/0
R 10.1.3.0 [120/1] via 10.1.4.1, 00:00:20, Serial0/0/0
from Corp
C 10.1.4.0 is directly connected, Serial0/0/0
R 10.1.5.0 [120/1] via 10.1.4.1, 00:00:20, Serial0/0/0
from Corp
172.16.0.0/16 is variably subnetted, 2 subnets, 2 masks
R 172.16.0.0/16 [120/2] via 10.1.4.1, 00:00:20, Serial0/0/0
S 172.16.10.0/24 [150/0] via 10.1.4.1
from R3 via Corp
R 192.168.10.0/24 [120/2] via 10.1.4.1, 00:00:20, Serial0/0/0
R 192.168.20.0/24 [120/2] via 10.1.4.1, 00:00:20, Serial0/0/0
from R1 via Corp
C 192.168.30.0/24 is directly connected, FastEthernet0/0
C 192.168.40.0/24 is directly connected, FastEthernet0/1
R1 before R3 RIP
R1#
show ip route
10.0.0.0/24 is subnetted, 5 subnets
R 10.1.1.0 [120/1] via 10.1.2.1, 00:00:04, Serial0/0/0
[120/1] via 10.1.3.1, 00:00:04, Serial0/0/1
C 10.1.2.0 is directly connected, Serial0/0/0
C 10.1.3.0 is directly connected, Serial0/0/1
R 10.1.4.0 [120/1] via 10.1.2.1, 00:00:04, Serial0/0/0
[120/1] via 10.1.3.1, 00:00:04, Serial0/0/1
R 10.1.5.0 [120/1] via 10.1.2.1, 00:00:04, Serial0/0/0
[120/1] via 10.1.3.1, 00:00:04, Serial0/0/1
from Corp
172.16.0.0/24 is subnetted, 1 subnets
S 172.16.10.0 [150/0] via 10.1.3.1
C 192.168.10.0/24 is directly connected, FastEthernet0/0
C 192.168.20.0/24 is directly connected, FastEthernet0/1
R 192.168.30.0/24 [120/2] via 10.1.2.1, 00:00:04, Serial0/0/0
[120/2] via 10.1.3.1, 00:00:04, Serial0/0/1
R 192.168.40.0/24 [120/2] via 10.1.2.1, 00:00:04, Serial0/0/0
[120/2] via 10.1.3.1, 00:00:04, Serial0/0/1
from R2 via Corp
R1 after R3 RIP
R1#
show ip route
10.0.0.0/24 is subnetted, 5 subnets
R 10.1.1.0 [120/1] via 10.1.3.1, 00:00:03, Serial0/0/1
[120/1] via 10.1.2.1, 00:00:03, Serial0/0/0
C 10.1.2.0 is directly connected, Serial0/0/0
C 10.1.3.0 is directly connected, Serial0/0/1
R 10.1.4.0 [120/1] via 10.1.3.1, 00:00:03, Serial0/0/1
[120/1] via 10.1.2.1, 00:00:03, Serial0/0/0
R 10.1.5.0 [120/1] via 10.1.3.1, 00:00:03, Serial0/0/1
[120/1] via 10.1.2.1, 00:00:03, Serial0/0/0
from Corp
172.16.0.0/16 is variably subnetted, 2 subnets, 2 masks
R 172.16.0.0/16 [120/2] via 10.1.3.1, 00:00:03, Serial0/0/1
[120/2] via 10.1.2.1, 00:00:03, Serial0/0/0
S 172.16.10.0/24 [150/0] via 10.1.3.1
from R3 via Corp
C 192.168.10.0/24 is directly connected, FastEthernet0/0
C 192.168.20.0/24 is directly connected, FastEthernet0/1
R 192.168.30.0/24 [120/2] via 10.1.3.1, 00:00:03, Serial0/0/1
[120/2] via 10.1.2.1, 00:00:03, Serial0/0/0
R 192.168.40.0/24 [120/2] via 10.1.3.1, 00:00:03, Serial0/0/1
[120/2] via 10.1.2.1, 00:00:03, Serial0/0/0
from R2 via Corp
Verifying Configurations
in addition to
show ip route
we can also use
show ip protocols
and
debug rip ip
Corp#
show ip protocols
Routing Protocol is "rip"
Sending updates every 30 seconds, next due in 11 seconds
Invalid after 180 seconds, hold down 180, flushed after 240
Outgoing update filter list for all interfaces is not set
Incoming update filter list for all interfaces is not set
Redistributing: rip
Default version control: send version 1, receive any version
Interface Send Recv Triggered RIP Key-chain
Vlan1 1 2 1
FastEthernet0/0 1 2 1
Serial0/0/1 1 2 1
Serial0/1/0 1 2 1
Serial0/0/0 1 2 1
Automatic network summarization is in effect
Maximum path: 4
Routing for Networks:
10.0.0.0
Passive Interface(s):
Routing Information Sources:
Gateway Distance Last Update
10.1.5.2 120 00:00:00
10.1.3.2 120 00:00:10
10.1.2.2 120 00:00:10
10.1.4.2 120 00:00:20
Distance: (default is 120)
R3#
debug ip rip
R3#RIP: received v1 update from 10.1.5.1 on FastEthernet0/0
10.1.1.0 in 1 hops
10.1.2.0 in 1 hops
10.1.3.0 in 1 hops
10.1.4.0 in 1 hops
192.168.10.0 in 2 hops
192.168.20.0 in 2 hops
192.168.30.0 in 2 hops
192.168.40.0 in 2 hops
R3#RIP: sending v1 update to 255.255.255.255 via Dot11Radio0/0/0 (172.16.10.1)
RIP: build update entries
network 10.0.0.0 metric 1
network 192.168.10.0 metric 3
network 192.168.20.0 metric 3
network 192.168.30.0 metric 3
network 192.168.40.0 metric 3
RIP: sending v1 update to 255.255.255.255 via FastEthernet0/0 (10.1.5.2)
RIP: build update entries
network 172.16.0.0 metric 1
output loops until manually disabled..............
R3#
undebug all
All possible debugging has been turned off
Note that due to the Split Horizon rule, R3 is not sending all of it's known RIP data to Corp.
It is sending all known RIP data out of the wifi interface (even there though there's no router that way),
but it is ONLY sending data about the wifi network back to Corp; data that Corp doesnt already have
Now lets look at some examples with sample routers..
I got hung up on these two examples because I found the
wording to be a bit confusing. Also there was subnetting involved that I was able to figure out, but threw me at first
First source of confusion- we have two seperate examples, and I was mixing them up.
The examples are:
Use the debug ip rip command to both:
discover a problem
and figure out how RIP was configured on a router from a different sample network
The conclusion regarding 'figuring out how RIP is configured' on this router, is that RIP networks are set as 10.0.0.0 and 172.16.0.0.
We determined that we are not the 'first source' of info on the 192.168.1.0 nertwork, since it is a metric of 2. We are sending out RIP data on that network,
but that RIP data is made availbale to us via another router.
I also got tripped up on the fact that RA is sending out S0/0 which corresponds 10.0.8.1,
and then receiving on the same interface S0/0 from an ip address of 10.0.15.0 on the other side of the link
I was able to determine that these two address are actually on the same subnet. My initial assumption was that the network address for the link is 10.0.0.0.
The problem doesn't give the subnet mask- I guessed it as /20 by using a 16 block since we can see that the third octet seems to move in 8's
if the network starts at 10.0.0.0 and we use /20 with 16 block, we would indeed have a last host address of 10.0.15.254, so 10.0.15.2 would be a valid host.
So there was a twist to this problem which needed subnetting to solve. It wasnt particulary releveant to the subject of RIP, but I was curious why the address on
the other side of that link looked so strange.
The problem also points out that we can determine there are 'at least' two routers participating in RIP here since we are sending RIP data out two interfaces but
only receiving RIP data on one interface. I'm unclear on why its worded this way; we know we are a RIP router- the fact that we are receiving data on one interface
would suggest there is 'at least one more' RIP router out there.
that's it for this example. Back to the original statement-
Use the debug ip rip command to both discover a problem and figure out
how RIP was configured on a router from a different sample network
We just 'figured out how RIP was configured on a router'.. The second example is regarding 'discovering a problem', although it is mentioned first.
The second example will use debug ip rip and show ip route to find a problem with the network
it looks like RIP data for 172.16.20.0 was received on S0/0, and then that interface was bumped out of the routing table entry for that network in favor of a static route.
ok, moving on now to RIP V2
RIP V2
enable it on all four routers
Corp(config)
router rip
Corp(config-router)
version 2
R1(config)
router rip
R1(config-router)
version 2
R2(config)
router rip
R2(config-router)
version 2
R3(config)
router rip
R3(config-router)
version 2
We'll use R1 to compare RIPv1 and RIPv2
RIPv1
R1(config)
debug ip rip
R1#RIP: sending v1 update to 255.255.255.255 via FastEthernet0/0 (192.168.10.1)
RIP: build update entries
network 10.0.0.0 metric 1
network 172.16.0.0 metric 3
network 192.168.20.0 metric 1
network 192.168.30.0 metric 3
network 192.168.40.0 metric 3
RIP: sending v1 update to 255.255.255.255 via FastEthernet0/1 (192.168.20.1)
RIP: build update entries
network 10.0.0.0 metric 1
network 172.16.0.0 metric 3
network 192.168.10.0 metric 1
network 192.168.30.0 metric 3
network 192.168.40.0 metric 3
RIP: sending v1 update to 255.255.255.255 via Serial0/0/0 (10.1.2.2)
RIP: build update entries
network 10.1.3.0 metric 1
network 192.168.10.0 metric 1
network 192.168.20.0 metric 1
RIP: sending v1 update to 255.255.255.255 via Serial0/0/1 (10.1.3.2)
RIP: build update entries
network 10.1.2.0 metric 1
network 192.168.10.0 metric 1
network 192.168.20.0 metric 1
RIPv2
R1(config)
debug ip rip
R1#RIP: sending v2 update to 224.0.0.9 via FastEthernet0/0 (192.168.10.1)
RIP: build update entries
10.0.0.0/8 via 0.0.0.0, metric 1, tag 0
172.16.0.0/16 via 0.0.0.0, metric 3, tag 0
192.168.20.0/24 via 0.0.0.0, metric 1, tag 0
192.168.30.0/24 via 0.0.0.0, metric 3, tag 0
192.168.40.0/24 via 0.0.0.0, metric 3, tag 0
RIP: sending v2 update to 224.0.0.9 via FastEthernet0/1 (192.168.20.1)
RIP: build update entries
10.0.0.0/8 via 0.0.0.0, metric 1, tag 0
172.16.0.0/16 via 0.0.0.0, metric 3, tag 0
192.168.10.0/24 via 0.0.0.0, metric 1, tag 0
192.168.30.0/24 via 0.0.0.0, metric 3, tag 0
192.168.40.0/24 via 0.0.0.0, metric 3, tag 0
RIP: sending v2 update to 224.0.0.9 via Serial0/0/0 (10.1.2.2)
RIP: build update entries
10.1.3.0/24 via 0.0.0.0, metric 1, tag 0
192.168.10.0/24 via 0.0.0.0, metric 1, tag 0
192.168.20.0/24 via 0.0.0.0, metric 1, tag 0
RIP: sending v2 update to 224.0.0.9 via Serial0/0/1 (10.1.3.2)
RIP: build update entries
10.1.2.0/24 via 0.0.0.0, metric 1, tag 0
192.168.10.0/24 via 0.0.0.0, metric 1, tag 0
192.168.20.0/24 via 0.0.0.0, metric 1, tag 0
R1(config)
show ip protocols
Routing Protocol is "rip"
Sending updates every 30 seconds, next due in 13 seconds
Invalid after 180 seconds, hold down 180, flushed after 240
Outgoing update filter list for all interfaces is not set
Incoming update filter list for all interfaces is not set
Redistributing: rip
Default version control: send version 2, receive 2
Interface Send Recv Triggered RIP Key-chain
FastEthernet0/0 2 2
FastEthernet0/1 2 2
Serial0/0/0 2 2
Serial0/0/1 2 2
Automatic network summarization is in effect
Maximum path: 4
Routing for Networks:
10.0.0.0
192.168.10.0
192.168.20.0
Passive Interface(s):
Routing Information Sources:
Gateway Distance Last Update
10.1.3.1 120 00:00:21
10.1.2.1 120 00:00:21
Distance: (default is 120)
final task of this chapter
Enable a default route out to the internet , and advertise via RIP
R3(config)#
interface s0/1/0 (this is only for example, so I am not adding a serial card to R3)
R3(config-if)#
ip addr 172.16.10.5 255.255.255.252
R3(config-if)#
exit
R3(config)#
ip route 0.0.0.0 0.0.0.0 s0/0
R3(config)#
ip default-network 172.16.0.0 tells other routers via RIP that default WAN route is through R3
Chapter 8 Exam Essentials IP Routing
1. Describe the Basic IP routing process
frame changes at each hop, but packet doesnt change EXCEPT that the TTL field in the IP header decrements
2. List the information required by a router to successfully route packets
destination IP address, location of other routers, possible routers to all remote networks,
the best route to each network, how to maintain and maintain routing info
3. Describe how MAC addresses are used during the routing process
a MAC will never pass a router interface. MACs will change between router interfaces
4. View and interpret the routing table of a router
use show ip route to see the table
a "C" indicates directly connected, an "R" indicates RIP provided the route info, "S" means static
5. differentiate the three types of routing
static- manually configured
dynamic- routers automatically share info via protocol
default- a special route is configured for all traffic without a more specific destination network found in the table
6. Compare and contrast static and dynamic routing
static routing creates no routing update traffic which means less overhead on the routers and links- but it must be
configured manually and can't react if links are lost.
dynamic routing creates update traffic, but it can react to outages and choose the best route when multiple routes exist to the same network
7. Configure static routes at the CLI
route [dest network] [mask] [next hop address OR exit interface] [admin distance] [permanent]
Ex:
Corp(config)#
ip route 192.168.10.0 255.255.255.0 10.1.2.2 150
8. Create a default route
ip route 0.0.0.0 0.0.0.0 [ip address OR exit interface]
Ex:
R3(config)#
ip route 0.0.0.0 0.0.0.0 10.1.5.1 (ingress at Corp router- use if R3 cant identify route)
9. Understand administrative distance and its role in the selection of the best route
an integer from 0 (most trusted) to 255 (no traffic will pass via this route).
All routing protocols are assigned an AD but it can be changed at the CLI
10. Differentiate distance-vector, link-state, and hybrid routing protocols
distance vector- based on hop count (RIP)
link-state- multiple factors such as bandwidth and delay
hybrid- uses both
11. List mechanisms used to prevent routing loops in the network
max hop count, split horizon, route poisoning, holddown counters
12. Describe the counts used the operation of RIP
route update timer- (30) interval between routing updates
route invalid timer- (180, update x 3) before a route is determined invalid
holddown timer-(180) time info is supressed when a link is lost
route flush timer- (240) seconds before invalid and removal
13. Configure RIP routing
router rip
network x.x.x.x
the network(s) you want to advertise from your router. It only works if the other router has RIP enabled.
By enabling RIP, you are able to RECEIVE RIP data from other RIP routers.
by specifying a network, you are SENDING RIP data on that network
14. Identify commands used to verify RIP routing
show ip route will provide contents of the routing table with codes (R, C, S)
debug ip rip will show RIP updates being sent and received
15. Describe the differences between RIPv1 and RIPv2
RIPv1 sends a broadcast (255.255.255.255) every 30 seconds and has an AD of 120.
RIPv1 is classful only, does not send any mask info. No authentication between routers.
RIPv2 sends multicasts (224.0.0.9) every 30 seconds and sends mask info, which allows it to support classless networking, RIPv2 also supports
autentication between routers.
Chapter 8 Written Lab 8.0
1. At the appropriate prompt, create a static route to network 172.16.10.0/24 with a next-hop
gateway of 172.16.20.1 and an administrative distance of 150.
Router(config)#
ip route 172.16.10.0 255.255.255.0 172.16.20.1 150
2. When a PC sends a packet to another PC in a remote network, what destination IP address and MAC address will
be in the frame that it sends to it's default gateway?
the gateway interface MAC and the remote PC's IP
3. At the appropriate prompt, create a default route to 172.16.40.1
Router(config)#
ip route 0.0.0.0 0.0.0.0 172.16.40.1
"to" is the wrong word.. we are going TO any route VIA 172.16.40.1
4. If you are using default routing in a classless environment, what command must also be used?
Router(config)#
ip classless
5. On which type of network is a default route most beneficial?
stub
6. At the appropriate prompt, display the routing table on your router
Router#
show ip route
7. When creating a static or default route, you dont have to use the next-hop ip address;
you can instead use the ____________
exit interface
8. True/False: To reach a destination host, you must know the MAC address of the remote host
false, you need the MAC of your router
9. True/False: To reach a destination host, you must know the IP address of the remote host
true
10. At the appropriate prompt, execute the command required on a DCE serial interface that is not required
on a DTE serial interface
Router(config-if)#
clock rate X
11. At the appropriate prompt, enable RIP routing on the interface with the IP address 10.0.0.1/24
Router(config)#
router rip
Router(config-router)#
network 10.0.0.0
RIPv1 is CLASSFUL only... use the classful mask based on the first octet given
12. At the appropriate prompt, prevent a router from propagating IP information out serial 1
Router(config)#
router rip
Router(config-router)#
passive-interface S0/1
can receive RIP data but will not send
13. What routing loop prevention mechanism sends out a maximum hop count as soon as a link fails?
route poisoning
14. What routing loop prevention mechanism suppresses the resending of routing information to an interface
through which it was received?
split horizon
15. At the appropriate prompt display RIP routing updates as they are sent and received on the router
to the console session
Router#
debug ip rip
to turn it off:
Router#
undebug all
Chapter 8 Hands-on Labs
For these labs we will need a network with three routers.
Lab 8.1 Creating Static routes
first set the interfaces, then program the static routes
LabA(config)#
int s0/0/0
LabA(config-if)#
ip addr 172.16.20.1
LabA(config-if)#
int f0/0
LabA(config-if)#
ip addr 172.16.10.1
-----------------------------------------------------------------
LabA(config)#
ip route 172.16.30.0 255.255.255.0 172.16.20.2
LabA(config)#
ip route 172.16.40.0 255.255.255.0 172.16.20.2
LabB(config)#
int s0/0/0
LabB(config-if)#
ip addr 172.16.20.2
LabB(config-if)#
int s0/0/1
LabB(config-if)#
ip addr 172.16.30.1
-----------------------------------------------------------------
LabB(config)#
ip route 172.16.10.0 255.255.255.0 172.16.20.1
LabB(config)#
ip route 172.16.40.0 255.255.255.0 172.16.30.2
LabC(config)#
int s0/0/0
LabC(config-if)#
ip addr 172.16.30.2
LabC(config-if)#
int f0/0
LabC(config-if)#
ip addr 172.16.40.1
-----------------------------------------------------------------
LabC(config)#
ip route 172.16.10.0 255.255.255.0 172.16.30.1
LabC(config)#
ip route 172.16.20.0 255.255.255.0 172.16.30.1
Lab 8.2 RIP Configuration
remove the static routes, enable and configure RIP with the classful network id that covers the routes you want to advertise
LabA(config)#
no ip route 172.16.30.0 255.255.255.0 172.16.20.2
LabA(config)#
no ip route 172.16.40.0 255.255.255.0 172.16.20.2
LabA(config)#
router rip
LabA(config-router)#
network 172.16.0.0
LabA(config-router)#
do show ip route
Gateway of last resort is not set
172.16.0.0/16 is variably subnetted, 5 subnets, 2 masks
C 172.16.10.0/24 is directly connected, FastEthernet0/0
L 172.16.10.1/32 is directly connected, FastEthernet0/0
C 172.16.20.0/24 is directly connected, Serial0/0/0
L 172.16.20.1/32 is directly connected, Serial0/0/0
R 172.16.30.0/24 [120/1] via 172.16.20.2, 00:00:07, Serial0/0/0
from Lab B
LabB(config)#
no ip route 172.16.10.0 255.255.255.0 172.16.20.1
LabB(config)#
no ip route 172.16.40.0 255.255.255.0 172.16.30.2
LabB(config)#
router rip
LabB(config-router)#
network 172.16.0.0
LabB(config-router)#
do show ip route
Gateway of last resort is not set
172.16.0.0/16 is variably subnetted, 5 subnets, 2 masks
R 172.16.10.0/24 [120/1] via 172.16.20.1, 00:00:13, Serial0/0/0
from LabA
C 172.16.20.0/24 is directly connected, Serial0/0/0
L 172.16.20.2/32 is directly connected, Serial0/0/0
C 172.16.30.0/24 is directly connected, Serial0/0/1
L 172.16.30.1/32 is directly connected, Serial0/0/1
LabC(config)#
no ip route 172.16.10.0 255.255.255.0 172.16.30.1
LabC(config)#
no ip route 172.16.20.0 255.255.255.0 172.16.30.1
LabC(config)#
router rip
LabC(config-router)#
network 172.16.0.0
LabC(config-router)#
do show ip route
Gateway of last resort is not set
172.16.0.0/16 is variably subnetted, 3 subnets, 2 masks
R 172.16.20.0/24 [120/1] via 172.16.30.1, 00:00:05, Serial0/0/0
from LabB
C 172.16.30.0/24 is directly connected, Serial0/0/0
L 172.16.30.2/32 is directly connected, Serial0/0/0
Chapter 8 Review Questions
1. The Acme company uses a router named Gateway to connect to its ISP. The address of the ISP router is 206.143.5.2.
Which three commands could be configured on the gateway router to allow internet access to the entire network?
Set a default route:
Gateway(config)#
ip route 0.0.0.0 0.0.0.0 206.143.5.2 next hop IP
Gateway(config)#
ip route 0.0.0.0 0.0.0.0 S/0 exit interface instead of next hop IP
Gateway(config)#
ip default-network 206.143.5.0 next hop IP
2. What command will prevent RIP routing updates from exiting an interface but will sill allow the interface to receive RIP updates?
Router(config-if)#
passive-interface
3. Which two statemnts are true about ip route 172.16.4.0 255.255.255.0 192.168.4.2?
the command establishes a static route
the default admin distance is used (since we didnt give an AD argument)
4. What two destination addresses will be used by HostA to send data to the HTTPS server as shown in the following network?
MAC of RouterA f0/0 interface
IP address of the server
5. Which two statements are true about this output?
RIP: received v1 update from 192.168.40.2 on S0/1
192.168.50.0 in 16 hops (inaccessible)
RIP: sending v1 update to 255.255.255.255 via F0/0 (192.168.30.1)
RIP: build update entries
network 192.168.20.0 metric 1
network 192.168.40.0 metric 1
network 192.168.50.0 metric 16
RIP: sending v1 update to 255.255.255.255 via S0/1 (192.168.40.1)
true:
there are at least two routers exchanging information
192.168.40.2 will be successful
FALSE
there are three interfaces on the router participating in this update
false because we only see two interfaces represented in the output: S0/1(twice) and F0/0
a ping to 192.168.50.1 will be successful
false because that route has a metric of 16; it's unreachable
6. Describe split horizon
will not advertise a route back the the same router it was learned from
7. Which would be true if HostA is trying to communicate to HostB and interface F0/0 of RouterC goes down, as shown in the graphic?
RouterC will send an ICMP 'destination unreachable type' message to inform HostA that HostB is unreachable
8. Which two statements are true regarding classless routing protocols?
VLSM is permitted
RIPv2 supports classless
9. Which two are true regarding distance-vector vs link-state?
Distance vector sends the whole routing table out all active interfaces(even if a router isnt on the other end)at periodic time intervals
Link-state sends updates containing the state of its own links to all routers in the inter-network
10. Which command display RIP routing updates?
debug ip rip
11. What does RIPv2 use to prvent routing loops?
split horizon stops an update from being send on the same interface it was received
holdown timers allow time for a network to become stable in the case of a flapping link
12. A network administrator views the output from the show ip route command. A network that is advertised
by both RIP and EIGRP appears in the routing table flagged an EIGRP route. Why is the RIP route to this network not used in this routing table?
EIGRP has a lower AD.
RIP=120
OSPP=110
IGRP=110
EIGRP=90
13. You type debug ip rip on your router console and see that 172.16.10.0 is being advertised to you with a metric of 16. What does this mean?
it is inaccessible. in RIP if you see a route advertised with a metric of 16, it's inaccessible
14. What metric does RIPv2 use to find the best path to the remote network?
distance aka hop count
15. The Corporate router receives an IP packet with a source IP address of 192.168.214.20 and a destination address of 192.168.22.3. Looking at the output from the Corp router,
what will the router do with this packet?
Corp# show ip route
[cut]
R 192.168.215.0 [120/2] via 192.168.20.2, Serail0/0
R 192.168.115.0 [120/1] via 192.168.20.0, Serial0/0
R 192.168.30.0 [120/1] via 192.168.20.2, Serial0/0
C 192.168.20.0 is directly connected, Serial0/0
C 192.168.214.0 is directly connected, FastEthernet0/0
Since there is no route to that network, the router will discard the packet and send an ICMP destination unreachable message out F0/0 back the the source network
16. If your routing table has a static, a RIP and an EIGRP route to the same network, which route will be used by default?
Static routes have an admin distance of 1 by default. Unless you change it, a static route will always be used over any other
dynamically learned route.
17. You have the following routing table. Which network will NOT be placed in the neighbor routing table?
R 192.168.30.0/24 [120/1] via 192.168.40.1, Serial 0
C 192.168.40.0/24 is directly connected, Serial 0
172.16.0.0/2 is subnetted, 1 subnets
C 172.16.30.0 is directly connected, Loopback0
R 192.168.20.0/24 [120/1] via 192.168.40.1, Serial 0
R 10.0.0.0/8 [120/15] via 192.168.40.1, Serial 0
C 192.168.50.0/24 is directly connected, Ethernet 0
10.0.0.0 cant be placed in neighboring routing table because it is at 15 hops. 16 hops is invalid in RIP
18. Two connected routers are configured only with RIP. What will be the result when a router receives a routing update that contains a
higher-cost path to a network already in it's routing table?
The router will ignore the update because it is higher cost. When a routing update is received, the router first checks the AD and always chooses
the route with the lowest AD.
19.Which is true about route poisoning?
The router sets the metric for a downed link to "infinity".
20. Which is true about RIPv2?
it has all the same timers as RIPv1
------------------------------------------------------------------------------
END CHAPTER 8
54 hours 1-28 thru 2-14-22
original total 143 hours
11.5 hours review 12-23,24,26-22
review total hours 32
book page 428/822
avg 20 min/page (reading and exercises/labs)
Chapter 9 EIGRP and OSPF
pages 427-502, start 2-14-22-M
What is EIGRP?
Note it's not officially on CCNA 200-301 but it is still important to learn
Enhanced IGRP is a classless, enchanced distance vector protocol that uses the concept of an autonomous system to describe
the set of contigous routers that run the same routing protocol and share routing information.
Features:
Support for IP and IPv6 via protocol-dependent modules (seperate routing tables)
Considered classless
Support for summaries and discontiguous networks
Eficient neighbor discovery
communication via RTP- Reliable Transport Protocol
best path selection via Diffusing Updae Algorithm DUAL
Cisco considers EIGRP a "distance-vector" routing protocol
or an "advanced distance-vector" protocol
or a "hybrid" protocol
Configuring EIGRP on our network
------------------------------------------------------------------------------------------------------------------------------------
Corp(config)#
router eigrp ?
<1-65535> Autonomous system number
Corp(config)#
router eigrp 10
R2(config-router)#
network 10.0.0.0
after eigrp on R1- links from Corp to R1 are up
%DUAL-5-NBRCHANGE: IP-EIGRP 10: Neighbor 10.1.3.2 (Serial0/0/1) is up: new adjacency
%DUAL-5-NBRCHANGE: IP-EIGRP 10: Neighbor 10.1.2.2 (Serial0/0/0) is up: new adjacency
after eigrp on R2- link from Corp to R2 is up
%DUAL-5-NBRCHANGE: IP-EIGRP 10: Neighbor 10.1.4.2 (Serial0/1/0) is up: new adjacency
after eigrp on R3- link from Corp to R3 is up
%DUAL-5-NBRCHANGE: IP-EIGRP 10: Neighbor 10.1.5.2 (FastEthernet0/0) is up: new adjacency
------------------------------------------------------------------------------------------------------------------------------------
R1(config)#
router eigrp 10
R1(config-router)#
network 10.0.0.0
after eigrp on R1- link from R1 to Corp is up
%DUAL-5-NBRCHANGE: IP-EIGRP 10: Neighbor 10.1.3.1 (Serial0/0/1) is up: new adjacency
%DUAL-5-NBRCHANGE: IP-EIGRP 10: Neighbor 10.1.2.1 (Serial0/0/0) is up: new adjacency
R1(config-router)#
network 192.168.10.0
R1(config-router)#
network 192.168.20.0
------------------------------------------------------------------------------------------------------------------------------------
R2(config)#
router eigrp 10
R2(config-router)#
network 10.0.0.0
after eigrp on R2- link from R2 to Corp is up
%DUAL-5-NBRCHANGE: IP-EIGRP 10: Neighbor 10.1.4.1 (Serial0/0/0) is up: new adjacency
R1(config-router)#
network 192.168.30.0
R1(config-router)#
network 192.168.40.0
------------------------------------------------------------------------------------------------------------------------------------
R3(config)#
router eigrp 10
R3(config-router)#
network 10.0.0.0
after eigrp on R3- link from R3 to Corp is up
%DUAL-5-NBRCHANGE: IP-EIGRP 10: Neighbor 10.1.5.1 (FastEthernet0/0) is up: new adjacency
R1(config-router)#
network 172.16.0.0
------------------------------------------------------------------------------------------------------------------------------------
Corp#
show ip route
Gateway of last resort is not set
Gateway of last resort is not set
10.0.0.0/8 is variably subnetted, 10 subnets, 2 masks
C 10.1.1.0/24 is directly connected, Vlan1
L 10.1.1.1/32 is directly connected, Vlan1
C 10.1.2.0/24 is directly connected, Serial0/0/0
L 10.1.2.1/32 is directly connected, Serial0/0/0
C 10.1.3.0/24 is directly connected, Serial0/0/1
L 10.1.3.1/32 is directly connected, Serial0/0/1
C 10.1.4.0/24 is directly connected, Serial0/1/0
L 10.1.4.1/32 is directly connected, Serial0/1/0
C 10.1.5.0/24 is directly connected, FastEthernet0/0
L 10.1.5.1/32 is directly connected, FastEthernet0/0
172.16.0.0/16 is variably subnetted, 2 subnets, 2 masks
R 172.16.0.0/16 [120/1] via 10.1.5.2, 00:00:17, FastEthernet0/0
D 172.16.10.0/24 [90/28160] via 10.1.5.2, 00:00:16, FastEthernet0/0
via R3
D 192.168.10.0/24 [90/2172416] via 10.1.2.2, 00:19:13, Serial0/0/0
[90/2172416] via 10.1.3.2, 00:19:13, Serial0/0/1
D 192.168.20.0/24 [90/2172416] via 10.1.3.2, 00:19:05, Serial0/0/1
[90/2172416] via 10.1.2.2, 00:19:05, Serial0/0/0
via R1
D 192.168.30.0/24 [90/2172416] via 10.1.4.2, 00:01:31, Serial0/1/0
D 192.168.40.0/24 [90/2172416] via 10.1.4.2, 00:01:08, Serial0/1/0
via R2
The "D" routes are for DUAL- Diffusing Update Algorithm, indicating they are EIGRP routes.
Note that we have RIP and EIGRP set currently
------------------------------------------------------------------------------------------------------------------------------------
R1#
show ip route
Gateway of last resort is not set
10.0.0.0/8 is variably subnetted, 6 subnets, 2 masks
D 10.0.0.0/8 is a summary, 00:25:28, Null0
D 10.1.1.0/24 [90/27769856] via 10.1.2.1, 00:31:33, Serial0/0/0
[90/27769856] via 10.1.3.1, 00:31:30, Serial0/0/1
via Corp
C 10.1.2.0/24 is directly connected, Serial0/0/0
C 10.1.3.0/24 is directly connected, Serial0/0/1
D 10.1.4.0/24 [90/2681856] via 10.1.2.1, 00:31:33, Serial0/0/0
[90/2681856] via 10.1.3.1, 00:31:30, Serial0/0/1
D 10.1.5.0/24 [90/2172416] via 10.1.2.1, 00:31:33, Serial0/0/0
[90/2172416] via 10.1.3.1, 00:31:30, Serial0/0/1
via Corp
172.16.0.0/16 is variably subnetted, 2 subnets, 2 masks
R 172.16.0.0/16 [120/2] via 10.1.2.1, 00:00:07, Serial0/0/0
[120/2] via 10.1.3.1, 00:00:07, Serial0/0/1
D 172.16.10.0/24 [90/2172416] via 10.1.2.1, 00:06:31, Serial0/0/0
[90/2172416] via 10.1.3.1, 00:06:31, Serial0/0/1
via Corp
C 192.168.10.0/24 is directly connected, FastEthernet0/0
C 192.168.20.0/24 is directly connected, FastEthernet0/1
D 192.168.30.0/24 [90/2684416] via 10.1.3.1, 00:07:46, Serial0/0/1
[90/2684416] via 10.1.2.1, 00:07:46, Serial0/0/0
D 192.168.40.0/24 [90/2684416] via 10.1.2.1, 00:07:23, Serial0/0/0
[90/2684416] via 10.1.3.1, 00:07:23, Serial0/0/1
via Corp
------------------------------------------------------------------------------------------------------------------------------------
R2#
show ip route
Gateway of last resort is not set
10.0.0.0/8 is variably subnetted, 6 subnets, 2 masks
D 10.0.0.0/8 is a summary, 00:13:09, Null0
D 10.1.1.0/24 [90/27769856] via 10.1.4.1, 00:36:53, Serial0/0/0
D 10.1.2.0/24 [90/2681856] via 10.1.4.1, 00:36:53, Serial0/0/0
D 10.1.3.0/24 [90/2681856] via 10.1.4.1, 00:36:53, Serial0/0/0
via Corp
C 10.1.4.0/24 is directly connected, Serial0/0/0
D 10.1.5.0/24 [90/2172416] via 10.1.4.1, 00:36:53, Serial0/0/0
via Corp
172.16.0.0/16 is variably subnetted, 2 subnets, 2 masks
R 172.16.0.0/16 [120/2] via 10.1.4.1, 00:00:23, Serial0/0/0
D 172.16.10.0/24 [90/2172416] via 10.1.4.1, 00:11:54, Serial0/0/0
via Corp
D 192.168.10.0/24 [90/2684416] via 10.1.4.1, 00:30:51, Serial0/0/0
D 192.168.20.0/24 [90/2684416] via 10.1.4.1, 00:30:43, Serial0/0/0
via Corp
C 192.168.30.0/24 is directly connected, FastEthernet0/0
C 192.168.40.0/24 is directly connected, FastEthernet0/1
------------------------------------------------------------------------------------------------------------------------------------
R3#
show ip route
Gateway of last resort is 10.1.5.1 to network 0.0.0.0
10.0.0.0/8 is variably subnetted, 6 subnets, 2 masks
D 10.1.1.0/24 [90/25628160] via 10.1.5.1, 00:37:20, FastEthernet0/0
D 10.1.2.0/24 [90/2172416] via 10.1.5.1, 00:37:15, FastEthernet0/0
D 10.1.3.0/24 [90/2172416] via 10.1.5.1, 00:37:20, FastEthernet0/0
D 10.1.4.0/24 [90/2172416] via 10.1.5.1, 00:37:20, FastEthernet0/0
via Corp
C 10.1.5.0/24 is directly connected, FastEthernet0/0
L 10.1.5.2/32 is directly connected, FastEthernet0/0
172.16.0.0/16 is variably subnetted, 2 subnets, 2 masks
C 172.16.10.0/24 is directly connected, Dot11Radio0/0/0
L 172.16.10.1/32 is directly connected, Dot11Radio0/0/0
D 192.168.10.0/24 [90/2174976] via 10.1.5.1, 00:31:10, FastEthernet0/0
D 192.168.20.0/24 [90/2174976] via 10.1.5.1, 00:31:02, FastEthernet0/0
via Corp and R1
D 192.168.30.0/24 [90/2174976] via 10.1.5.1, 00:13:28, FastEthernet0/0
D 192.168.40.0/24 [90/2174976] via 10.1.5.1, 00:13:05, FastEthernet0/0
via Corp and R2
S* 0.0.0.0/0 [1/0] via 10.1.5.1
------------------------------------------------------------------------------------------------------------------------------------
turn off auto summary on each router
------------------------------------------------------------------------------------------------------------------------------------
Corp(config)#
router eigrp 10
Corp(config-router)#
no auto-summary
------------------------------------------------------------------------------------------------------------------------------------
R1(config)#
router eigrp 10
R1(config-router)#
no auto-summary
------------------------------------------------------------------------------------------------------------------------------------
R2(config)#
router eigrp 10
R2(config-router)#
no auto-summary
------------------------------------------------------------------------------------------------------------------------------------
R3(config)#
router eigrp 10
R3(config-router)#
no auto-summary
------------------------------------------------------------------------------------------------------------------------------------
compare Corp before and after auto summary turned off
------------------------------------------------------------------------------------------------------------------------------------
auto summary on
Corp#
show ip route
Gateway of last resort is not set
10.0.0.0/8 is variably subnetted, 10 subnets, 2 masks
C 10.1.1.0/24 is directly connected, Vlan1
L 10.1.1.1/32 is directly connected, Vlan1
C 10.1.2.0/24 is directly connected, Serial0/0/0
L 10.1.2.1/32 is directly connected, Serial0/0/0
C 10.1.3.0/24 is directly connected, Serial0/0/1
L 10.1.3.1/32 is directly connected, Serial0/0/1
C 10.1.4.0/24 is directly connected, Serial0/1/0
L 10.1.4.1/32 is directly connected, Serial0/1/0
C 10.1.5.0/24 is directly connected, FastEthernet0/0
L 10.1.5.1/32 is directly connected, FastEthernet0/0
172.16.0.0/16 is variably subnetted, 2 subnets, 2 masks
R 172.16.0.0/16 [120/1] via 10.1.5.2, 00:00:17, FastEthernet0/0
D 172.16.10.0/24 [90/28160] via 10.1.5.2, 00:00:16, FastEthernet0/0
via R3
D 192.168.10.0/24 [90/2172416] via 10.1.2.2, 00:19:13, Serial0/0/0
[90/2172416] via 10.1.3.2, 00:19:13, Serial0/0/1
D 192.168.20.0/24 [90/2172416] via 10.1.3.2, 00:19:05, Serial0/0/1
[90/2172416] via 10.1.2.2, 00:19:05, Serial0/0/0
via R1
D 192.168.30.0/24 [90/2172416] via 10.1.4.2, 00:01:31, Serial0/1/0
D 192.168.40.0/24 [90/2172416] via 10.1.4.2, 00:01:08, Serial0/1/0
via R2
auto summary off
Corp#
show ip route
Gateway of last resort is not set
10.0.0.0/8 is variably subnetted, 10 subnets, 2 masks
C 10.1.1.0/24 is directly connected, Vlan1
L 10.1.1.1/32 is directly connected, Vlan1
C 10.1.2.0/24 is directly connected, Serial0/0/0
L 10.1.2.1/32 is directly connected, Serial0/0/0
C 10.1.3.0/24 is directly connected, Serial0/0/1
L 10.1.3.1/32 is directly connected, Serial0/0/1
C 10.1.4.0/24 is directly connected, Serial0/1/0
L 10.1.4.1/32 is directly connected, Serial0/1/0
C 10.1.5.0/24 is directly connected, FastEthernet0/0
L 10.1.5.1/32 is directly connected, FastEthernet0/0
172.16.0.0/16 is variably subnetted, 2 subnets, 2 masks
R 172.16.0.0/16 [120/1] via 10.1.5.2, 00:00:12, FastEthernet0/0
D 172.16.10.0/24 [90/28160] via 10.1.5.2, 00:45:29, FastEthernet0/0
via R3
D 192.168.10.0/24 [90/2172416] via 10.1.2.2, 00:01:08, Serial0/0/0
[90/2172416] via 10.1.3.2, 00:01:08, Serial0/0/1
D 192.168.20.0/24 [90/2172416] via 10.1.2.2, 00:01:08, Serial0/0/0
[90/2172416] via 10.1.3.2, 00:01:08, Serial0/0/1
via R1
D 192.168.30.0/24 [90/2172416] via 10.1.4.2, 00:00:46, Serial0/1/0
D 192.168.40.0/24 [90/2172416] via 10.1.4.2, 00:00:46, Serial0/1/0
via R2
We are still seeing an auto summarized route- 172.16.0.0 coming from R3.
The book discusses enabling EIGRP auto summary on all four routers- nothing is said about disabling it within RIP or turning off RIP.
RIP auto summarizes by default. We cant get rid of this auto summary route while RIP is on.
Moving on...
VERIFYING EIGRP
several commands available to verify and troubleshoot
show ip route
show the entire routing table
show ip route eigrp
show only EIGRP entries in the routing table
show ip eigrp neighbors
show all EIGRP neigbors
show ip eigrp topology
show entries in the EIGRP topology table
show ip protocols
shows routing protocols configuration
debug eigrp packet
shows hello packets sent/received between adjacent routers
debug ip eigrp events
shows EIGRP changes and updates as they occur on your network
lets take a look at the state of our 4 routers. RIP and EIGRP are running on each.
Notice how this command is giving different outputs between the two different IOS versions
IOS 15.1
Corp#
show ip protocols
Routing Protocol is "eigrp 10 "
Outgoing update filter list for all interfaces is not set
Incoming update filter list for all interfaces is not set
Default networks flagged in outgoing updates
Default networks accepted from incoming updates
Redistributing: eigrp 10
EIGRP-IPv4 Protocol for AS(10)
Metric weight K1=1, K2=0, K3=1, K4=0, K5=0
NSF-aware route hold timer is 240
Router-ID: 10.1.1.1
Topology : 0 (base)
Active Timer: 3 min
Distance: internal 90 external 170
Maximum path: 4
Maximum hopcount 100
Maximum metric variance 1
Automatic Summarization: disabled
Automatic address summarization:
Maximum path: 4
Routing for Networks:
10.0.0.0
Routing Information Sources:
Gateway Distance Last Update
10.1.5.2 90 0
10.1.3.2 90 6464
10.1.2.2 90 6795
10.1.4.2 90 7955
Distance: internal 90 external 170
Routing Protocol is "rip"
Sending updates every 30 seconds, next due in 10 seconds
Invalid after 180 seconds, hold down 180, flushed after 240
Outgoing update filter list for all interfaces is not set
Incoming update filter list for all interfaces is not set
Redistributing: rip
Default version control: send version 2, receive 2
Interface Send Recv Triggered RIP Key-chain
Vlan1 2 2
FastEthernet0/0 2 2
Serial0/1/0 2 2
Serial0/0/1 2 2
Serial0/0/0 2 2
Automatic network summarization is in effect
Maximum path: 4
Routing for Networks:
10.0.0.0
Passive Interface(s):
Routing Information Sources:
Gateway Distance Last Update
10.1.5.2 120 00:00:12
10.1.3.2 120 00:00:16
10.1.2.2 120 00:00:16
10.1.4.2 120 00:00:13
Distance: (default is 120)
IOS 12.4
R1#
show ip protocols
Routing Protocol is "eigrp 10 "
Outgoing update filter list for all interfaces is not set
Incoming update filter list for all interfaces is not set
Default networks flagged in outgoing updates
Default networks accepted from incoming updates
EIGRP metric weight K1=1, K2=0, K3=1, K4=0, K5=0
EIGRP maximum hopcount 100
EIGRP maximum metric variance 1
Redistributing: eigrp 10
Automatic network summarization is not in effect
Maximum path: 4
Routing for Networks:
10.0.0.0
192.168.10.0
192.168.20.0
Routing Information Sources:
Gateway Distance Last Update
10.1.3.1 90 6465
10.1.2.1 90 6794
Distance: internal 90 external 170
Routing Protocol is "rip"
Sending updates every 30 seconds, next due in 21 seconds
Invalid after 180 seconds, hold down 180, flushed after 240
Outgoing update filter list for all interfaces is not set
Incoming update filter list for all interfaces is not set
Redistributing: rip
Default version control: send version 2, receive 2
Interface Send Recv Triggered RIP Key-chain
FastEthernet0/0 2 2
FastEthernet0/1 2 2
Serial0/0/0 2 2
Serial0/0/1 2 2
Automatic network summarization is not in effect
Maximum path: 4
Routing for Networks:
10.0.0.0
192.168.10.0
192.168.20.0
Passive Interface(s):
Routing Information Sources:
Gateway Distance Last Update
10.1.3.1 120 00:00:06
10.1.2.1 120 00:00:06
Distance: (default is 120)
IOS 12.4
R2#
show ip protocols
Routing Protocol is "eigrp 10 "
Outgoing update filter list for all interfaces is not set
Incoming update filter list for all interfaces is not set
Default networks flagged in outgoing updates
Default networks accepted from incoming updates
EIGRP metric weight K1=1, K2=0, K3=1, K4=0, K5=0
EIGRP maximum hopcount 100
EIGRP maximum metric variance 1
Redistributing: eigrp 10
Automatic network summarization is not in effect
Maximum path: 4
Routing for Networks:
10.0.0.0
192.168.30.0
192.168.40.0
Routing Information Sources:
Gateway Distance Last Update
10.1.4.1 90 7955
Distance: internal 90 external 170
Routing Protocol is "rip"
Sending updates every 30 seconds, next due in 11 seconds
Invalid after 180 seconds, hold down 180, flushed after 240
Outgoing update filter list for all interfaces is not set
Incoming update filter list for all interfaces is not set
Redistributing: rip
Default version control: send version 2, receive 2
Interface Send Recv Triggered RIP Key-chain
FastEthernet0/0 2 2
FastEthernet0/1 2 2
Serial0/0/0 2 2
Automatic network summarization is in effect
Maximum path: 4
Routing for Networks:
10.0.0.0
192.168.30.0
192.168.40.0
Passive Interface(s):
Routing Information Sources:
Gateway Distance Last Update
10.1.4.1 120 00:00:20
Distance: (default is 120)
IOS 15.1
R3#
show ip protocols
Routing Protocol is "eigrp 10 "
Outgoing update filter list for all interfaces is not set
Incoming update filter list for all interfaces is not set
Default networks flagged in outgoing updates
Default networks accepted from incoming updates
Redistributing: eigrp 10
EIGRP-IPv4 Protocol for AS(10)
Metric weight K1=1, K2=0, K3=1, K4=0, K5=0
NSF-aware route hold timer is 240
Router-ID: 10.1.5.2
Topology : 0 (base)
Active Timer: 3 min
Distance: internal 90 external 170
Maximum path: 4
Maximum hopcount 100
Maximum metric variance 1
Automatic Summarization: disabled
Automatic address summarization:
Maximum path: 4
Routing for Networks:
10.0.0.0
172.16.0.0
Routing Information Sources:
Gateway Distance Last Update
10.1.5.1 90 0
Distance: internal 90 external 170
Routing Protocol is "rip"
Sending updates every 30 seconds, next due in 27 seconds
Invalid after 180 seconds, hold down 180, flushed after 240
Outgoing update filter list for all interfaces is not set
Incoming update filter list for all interfaces is not set
Redistributing: rip
Default version control: send version 2, receive 2
Interface Send Recv Triggered RIP Key-chain
Dot11Radio0/0/0 2 2
FastEthernet0/0 2 2
Automatic network summarization is not in effect
Maximum path: 4
Routing for Networks:
10.0.0.0
172.16.0.0
Passive Interface(s):
Routing Information Sources:
Gateway Distance Last Update
10.1.5.1 120 00:00:02
Distance: (default is 120)
I'm also noticing that we have inconsistent auto-summarization settings- I was having trouble with this earlier. The book discusses
getting rid of the 172.16.0.0 summarized route in the EIGRP settings. I was not able to get rid of it, I think because RIP is still on, and RIP forces auto-summary
Part of the challenge here is that the book is strictly dealing with IOS 12.4
I will now make sure to turn auto summary off for both RIP and EIGRP on each of the four routers.
OK the part I am forgetting is that we are running RIP V2 which does not force auto-summary but runs it optionally, and we must turn it off to avoid auto summarization.
Corp(config)#
router rip
Corp(config-router)#
no auto-summary
Corp(config-router)#
router eigrp 10
Corp(config-router)#
no auto-summary
R1(config)#
router rip
R1(config-router)#
no auto-summary
R1(config-router)#
router eigrp 10
R1(config-router)#
no auto-summary
R1(config)#
router rip
R1(config-router)#
no auto-summary
R1(config-router)#
router eigrp 10
R2(config-router)#
no auto-summary
R3(config)#
router rip
R3(config-router)#
no auto-summary
R3(config-router)#
router eigrp 10
R3(config-router)#
no auto-summary
and lets see how the output looks now. This time I'll do show ip protocols and
show ip route side by side for each router
IOS 15.1
Corp#
show ip protocols
Routing Protocol is "eigrp 10 "
Outgoing update filter list for all interfaces is not set
Incoming update filter list for all interfaces is not set
Default networks flagged in outgoing updates
Default networks accepted from incoming updates
Redistributing: eigrp 10
EIGRP-IPv4 Protocol for AS(10)
Metric weight K1=1, K2=0, K3=1, K4=0, K5=0
NSF-aware route hold timer is 240
Router-ID: 10.1.1.1
Topology : 0 (base)
Active Timer: 3 min
Distance: internal 90 external 170
Maximum path: 4
Maximum hopcount 100
Maximum metric variance 1
Automatic Summarization: disabled
Automatic address summarization:
Maximum path: 4
Routing for Networks:
10.0.0.0
Routing Information Sources:
Gateway Distance Last Update
10.1.5.2 90 0
10.1.3.2 90 6464
10.1.2.2 90 6795
10.1.4.2 90 7955
Distance: internal 90 external 170
Routing Protocol is "rip" doesnt necessarily mean RIPv1
Sending updates every 30 seconds, next due in 3 seconds
Invalid after 180 seconds, hold down 180, flushed after 240
Outgoing update filter list for all interfaces is not set
Incoming update filter list for all interfaces is not set
Redistributing: rip
Default version control: send version 2, receive 2 RIPv2 is specified
Interface Send Recv Triggered RIP Key-chain
Vlan1 2 2
FastEthernet0/0 2 2
Serial0/1/0 2 2
Serial0/0/1 2 2
Serial0/0/0 2 2
Automatic network summarization is not in effect
Maximum path: 4
Routing for Networks:
10.0.0.0
Passive Interface(s):
Routing Information Sources:
Gateway Distance Last Update
10.1.5.2 120 00:00:02
10.1.3.2 120 00:00:21
10.1.2.2 120 00:00:21
10.1.4.2 120 00:00:04
Distance: (default is 120)
IOS 15.1
Corp#
show ip route
Gateway of last resort is not set
10.0.0.0/8 is variably subnetted, 10 subnets, 2 masks
C 10.1.1.0/24 is directly connected, Vlan1
L 10.1.1.1/32 is directly connected, Vlan1
C 10.1.2.0/24 is directly connected, Serial0/0/0
L 10.1.2.1/32 is directly connected, Serial0/0/0
C 10.1.3.0/24 is directly connected, Serial0/0/1
L 10.1.3.1/32 is directly connected, Serial0/0/1
C 10.1.4.0/24 is directly connected, Serial0/1/0
L 10.1.4.1/32 is directly connected, Serial0/1/0
C 10.1.5.0/24 is directly connected, FastEthernet0/0
L 10.1.5.1/32 is directly connected, FastEthernet0/0
172.16.0.0/24 is subnetted, 1 subnets
D 172.16.10.0/24 [90/28160] via 10.1.5.2, 00:57:25, FastEthernet0/0
D 192.168.10.0/24 [90/2172416] via 10.1.3.2, 00:57:20, Serial0/0/1
[90/2172416] via 10.1.2.2, 00:57:20, Serial0/0/0
D 192.168.20.0/24 [90/2172416] via 10.1.3.2, 00:57:20, Serial0/0/1
[90/2172416] via 10.1.2.2, 00:57:20, Serial0/0/0
D 192.168.30.0/24 [90/2172416] via 10.1.4.2, 00:57:19, Serial0/1/0
D 192.168.40.0/24 [90/2172416] via 10.1.4.2, 00:57:19, Serial0/1/0
IOS 12.4
R1#
show ip protocols
Routing Protocol is "eigrp 10 "
Outgoing update filter list for all interfaces is not set
Incoming update filter list for all interfaces is not set
Default networks flagged in outgoing updates
Default networks accepted from incoming updates
EIGRP metric weight K1=1, K2=0, K3=1, K4=0, K5=0
EIGRP maximum hopcount 100
EIGRP maximum metric variance 1
Redistributing: eigrp 10
Automatic network summarization is not in effect
Maximum path: 4
Routing for Networks:
10.0.0.0
192.168.10.0
192.168.20.0
Routing Information Sources:
Gateway Distance Last Update
10.1.3.1 90 6465
10.1.2.1 90 6794
Distance: internal 90 external 170
Routing Protocol is "rip"
Sending updates every 30 seconds, next due in 26 seconds
Invalid after 180 seconds, hold down 180, flushed after 240
Outgoing update filter list for all interfaces is not set
Incoming update filter list for all interfaces is not set
Redistributing: rip
Default version control: send version 2, receive 2
Interface Send Recv Triggered RIP Key-chain
FastEthernet0/0 2 2
FastEthernet0/1 2 2
Serial0/0/0 2 2
Serial0/0/1 2 2
Automatic network summarization is not in effect
Maximum path: 4
Routing for Networks:
10.0.0.0
192.168.10.0
192.168.20.0
Passive Interface(s):
Routing Information Sources:
Gateway Distance Last Update
10.1.3.1 120 00:00:03
10.1.2.1 120 00:00:03
Distance: (default is 120)
IOS 12.4
R1#
show ip route
Gateway of last resort is not set
10.0.0.0/24 is subnetted, 5 subnets
D 10.1.1.0 [90/27769856] via 10.1.3.1, 00:54:47, Serial0/0/1
[90/27769856] via 10.1.2.1, 00:54:47, Serial0/0/0
C 10.1.2.0 is directly connected, Serial0/0/0
C 10.1.3.0 is directly connected, Serial0/0/1
D 10.1.4.0 [90/2681856] via 10.1.3.1, 00:54:47, Serial0/0/1
[90/2681856] via 10.1.2.1, 00:54:47, Serial0/0/0
D 10.1.5.0 [90/2172416] via 10.1.3.1, 00:54:47, Serial0/0/1
[90/2172416] via 10.1.2.1, 00:54:47, Serial0/0/0
172.16.0.0/24 is subnetted, 1 subnets
D 172.16.10.0 [90/2172416] via 10.1.3.1, 00:54:47, Serial0/0/1
[90/2172416] via 10.1.2.1, 00:54:47, Serial0/0/0
C 192.168.10.0/24 is directly connected, FastEthernet0/0
C 192.168.20.0/24 is directly connected, FastEthernet0/1
D 192.168.30.0/24 [90/2684416] via 10.1.3.1, 00:54:46, Serial0/0/1
[90/2684416] via 10.1.2.1, 00:54:46, Serial0/0/0
D 192.168.40.0/24 [90/2684416] via 10.1.3.1, 00:54:46, Serial0/0/1
[90/2684416] via 10.1.2.1, 00:54:46, Serial0/0/0
note that the DUAL routes being advertised from the 10.0.0.0 networks are all specific to the third octet.. that's because we are reading those routes
from their source, aka the router which they are directly connected to, Corp.
and on Corp, those networks were added to the interfaces with a /24 mask.
so even though our EIGRP config doesnt specifically include /24 networks.. we told it to include anything with a 10.x.x.x
Corp is advertising to R1 our /24 network interfaces that have a 10 in the first octet, EXCEPT the two which are directly connected to R1
10.1.1.0
10.1.4.0
10.1.5.0
are assumed to be the subnets based on the info we configured, which was 10.1.4.1/24 on corp, and 10.1.4.2/24 on r2 s0/0/0
nowhere in this configuration, have we entered the 10.1.4.0 network.
EIGRP is figuring it out based on the /24 mask we gave when assiging he IPs to the interfaces
IOS 12.4
R2#
show ip protocols
Routing Protocol is "eigrp 10 "
Outgoing update filter list for all interfaces is not set
Incoming update filter list for all interfaces is not set
Default networks flagged in outgoing updates
Default networks accepted from incoming updates
EIGRP metric weight K1=1, K2=0, K3=1, K4=0, K5=0
EIGRP maximum hopcount 100
EIGRP maximum metric variance 1
Redistributing: eigrp 10
Automatic network summarization is not in effect
Maximum path: 4
Routing for Networks:
10.0.0.0
192.168.30.0
192.168.40.0
Routing Information Sources:
Gateway Distance Last Update
10.1.4.1 90 7955
Distance: internal 90 external 170
Routing Protocol is "rip"
Sending updates every 30 seconds, next due in 18 seconds
Invalid after 180 seconds, hold down 180, flushed after 240
Outgoing update filter list for all interfaces is not set
Incoming update filter list for all interfaces is not set
Redistributing: rip
Default version control: send version 2, receive 2
Interface Send Recv Triggered RIP Key-chain
FastEthernet0/0 2 2
FastEthernet0/1 2 2
Serial0/0/0 2 2
Automatic network summarization is not in effect
Maximum path: 4
Routing for Networks:
10.0.0.0
192.168.30.0
192.168.40.0
Passive Interface(s):
Routing Information Sources:
Gateway Distance Last Update
10.1.4.1 120 00:00:07
Distance: (default is 120)
IOS 12.4
R2#
show ip route
Gateway of last resort is not set
10.0.0.0/24 is subnetted, 5 subnets
D 10.1.1.0 [90/27769856] via 10.1.4.1, 00:59:10, Serial0/0/0
D 10.1.2.0 [90/2681856] via 10.1.4.1, 00:59:10, Serial0/0/0
D 10.1.3.0 [90/2681856] via 10.1.4.1, 00:59:10, Serial0/0/0
C 10.1.4.0 is directly connected, Serial0/0/0
D 10.1.5.0 [90/2172416] via 10.1.4.1, 00:59:10, Serial0/0/0
172.16.0.0/24 is subnetted, 1 subnets
D 172.16.10.0 [90/2172416] via 10.1.4.1, 00:59:10, Serial0/0/0
D 192.168.10.0/24 [90/2684416] via 10.1.4.1, 00:59:10, Serial0/0/0
D 192.168.20.0/24 [90/2684416] via 10.1.4.1, 00:59:10, Serial0/0/0
C 192.168.30.0/24 is directly connected, FastEthernet0/0
C 192.168.40.0/24 is directly connected, FastEthernet0/1
IOS 15.1
R3#
show ip protocols
Routing Protocol is "eigrp 10 "
Outgoing update filter list for all interfaces is not set
Incoming update filter list for all interfaces is not set
Default networks flagged in outgoing updates
Default networks accepted from incoming updates
Redistributing: eigrp 10
EIGRP-IPv4 Protocol for AS(10)
Metric weight K1=1, K2=0, K3=1, K4=0, K5=0
NSF-aware route hold timer is 240
Router-ID: 10.1.5.2
Topology : 0 (base)
Active Timer: 3 min
Distance: internal 90 external 170
Maximum path: 4
Maximum hopcount 100
Maximum metric variance 1
Automatic Summarization: disabled
Automatic address summarization:
Maximum path: 4
Routing for Networks:
10.0.0.0
172.16.0.0
Routing Information Sources:
Gateway Distance Last Update
10.1.5.1 90 0
Distance: internal 90 external 170
Routing Protocol is "rip"
Sending updates every 30 seconds, next due in 15 seconds
Invalid after 180 seconds, hold down 180, flushed after 240
Outgoing update filter list for all interfaces is not set
Incoming update filter list for all interfaces is not set
Redistributing: rip
Default version control: send version 2, receive 2
Interface Send Recv Triggered RIP Key-chain
Dot11Radio0/0/0 2 2
FastEthernet0/0 2 2
Automatic network summarization is not in effect
Maximum path: 4
Routing for Networks:
10.0.0.0
172.16.0.0
Passive Interface(s):
Routing Information Sources:
Gateway Distance Last Update
10.1.5.1 120 00:00:14
Distance: (default is 120)
IOS 15.1
R3#
show ip route
Gateway of last resort is 10.1.5.1 to network 0.0.0.0
10.0.0.0/8 is variably subnetted, 6 subnets, 2 masks
D 10.1.1.0/24 [90/25628160] via 10.1.5.1, 00:59:52, FastEthernet0/0
D 10.1.2.0/24 [90/2172416] via 10.1.5.1, 00:59:47, FastEthernet0/0
D 10.1.3.0/24 [90/2172416] via 10.1.5.1, 00:59:52, FastEthernet0/0
D 10.1.4.0/24 [90/2172416] via 10.1.5.1, 00:59:52, FastEthernet0/0
C 10.1.5.0/24 is directly connected, FastEthernet0/0
L 10.1.5.2/32 is directly connected, FastEthernet0/0
172.16.0.0/16 is variably subnetted, 2 subnets, 2 masks
C 172.16.10.0/24 is directly connected, Dot11Radio0/0/0
L 172.16.10.1/32 is directly connected, Dot11Radio0/0/0
D 192.168.10.0/24 [90/2174976] via 10.1.5.1, 00:59:47, FastEthernet0/0
D 192.168.20.0/24 [90/2174976] via 10.1.5.1, 00:59:47, FastEthernet0/0
D 192.168.30.0/24 [90/2174976] via 10.1.5.1, 00:59:46, FastEthernet0/0
D 192.168.40.0/24 [90/2174976] via 10.1.5.1, 00:59:46, FastEthernet0/0
S* 0.0.0.0/0 [1/0] via 10.1.5.1
Observations:
Since this is a 15.1 router, we always get a "L" local route when
we have a "C" connected route. In R3's case, the 172.16.10.0 network
is directly connected. The interface which connects it, 172.16.10.1,
counts as a "local" route. This is NOT the case on the 12.4 routers.
looking to the left, our protocol output tells us two key facts for both EIGRP and RIP:
Routing for networks:
10.0.0.0
172.16.0.0
R3 is responsible for *sending* data about these two networks to our other EIGRP routers...
"I'm R3 and I can connect you to networks on the R3
router or networks on the Corp router"
Notice how the 192 networks arent listed. R3 isnt connected to a 192 network directly, nor is it connected to a neighbor who is directly connected.
If I, as a client, am sending data to a 192 network from the 172 network, I will start
at R3. Since R3 is receiving routes for the 192 networks via Corp, I will be able to reach a 192 network via Corp.
My connection to corp will happen VIA a "10.0.0.0" route.
R3 is technically only routing for 172 and 10 networks. Beyond that, it could potentially connect to many other different networks. But in terms of the R3 routing table,
all it can offer is a path out to the 172 network or the 10 network
Routing information sources:
10.1.5.1
In this case I can see that R3 is receiving routing data from one interface only,
and that is it's link to Corp. Some of the data we are receiving from Corp actually originates
at other routers, but we cant see that here; the data comes to us from Corp, and that is all we know
EIGRP TERMINOLOGY
FEASIBLE DISTANCE (FD)
the best metric among all paths, including to the next hop neighbor. You will only see the route with the lowest FD appear in the routing table
The FD is calculated by adding the reported distance from the neighbor (AD) plus the metric to that neighbor
ADVERTISED DISTANCE (AD)
the metric of a remote network as reported by a neighbor, listed second in parenthesis in toplogy table
P 192.168.20.0/24, 2 successors, FD is 2172416
via 10.1.3.2 (2172416/28160), Serial0/0/1
feasible / advertised
Neighbor Table
each router keeps state information about adjacent neighbors.. When a new neighbor is learned, the address and interface are recorded.
The neighbor table is stored in RAM.
Sequence numbres are used to match acks with update packets. The last squence number received from a neighbor is recorded so out of order packets
can be detected
Topology Table
acted upon by DUAL Diffusing Update Alogorithm. Contains all destinations advertised by neighboring routers.
For each neighbor, the adversited distance, which comes only from that neighbor's routing table, is recorded
The feasible distance is also recorded.
Feasible Successor
a PATH whose advertised distance is less than the feasible distance of the current succesor, and is considered a backup route.
EIGRP keeps up to 16 feasible successors in the toplogy table.
The one with the best metric (The Successor) is copied and placed into the routing table
Successor
the best route to a remote network, used by EIGRP to forward traffic. It's backed up by a feasible successor, if one is available.
lets demo some more of the commands
VERIFYING EIGRP
several commands available to verify and troubleshoot
show ip route
show the entire routing table
show ip route eigrp
show only EIGRP entries in the routing table
show ip eigrp neighbors
show all EIGRP neigbors
show ip eigrp topology
show entries in the EIGRP topology table
show ip protocols
shows routing protocols configuration
debug eigrp packet
shows hello packets sent/received between adjacent routers
debug ip eigrp events
shows EIGRP changes and updates as they occur on your network
Corp#
show ip eigrp ?
interfaces IP-EIGRP interfaces
neighbors IP-EIGRP neighbors
topology IP-EIGRP Topology Table
traffic IP-EIGRP Traffic Statistics
Corp#
show ip eigrp topology
IP-EIGRP Topology Table for AS 10/ID(10.1.5.1)
Codes: P - Passive, A - Active, U - Update, Q - Query, R - Reply,
r - Reply status
P 10.1.1.0/24, 1 successors, FD is 25625600
via Connected, Vlan1
P 10.1.2.0/24, 1 successors, FD is 2169856
via Connected, Serial0/0/0
P 10.1.3.0/24, 1 successors, FD is 2169856
via Connected, Serial0/0/1
P 10.1.4.0/24, 1 successors, FD is 2169856
via Connected, Serial0/1/0
P 10.1.5.0/24, 1 successors, FD is 28160
via Connected, FastEthernet0/0
P 172.16.10.0/24, 1 successors, FD is 28160
via 10.1.5.2 (28160/25600), FastEthernet0/0
P 192.168.10.0/24, 2 successors, FD is 2172416
via 10.1.3.2 (2172416/28160), Serial0/0/1
via 10.1.2.2 (2172416/28160), Serial0/0/0
P 192.168.20.0/24, 2 successors, FD is 2172416
via 10.1.3.2 (2172416/28160), Serial0/0/1
via 10.1.2.2 (2172416/28160), Serial0/0/0
P 192.168.30.0/24, 1 successors, FD is 2172416
via 10.1.4.2 (2172416/28160), Serial0/1/0
P 192.168.40.0/24, 1 successors, FD is 2172416
via 10.1.4.2 (2172416/28160), Serial0/1/0
the "P" preceding each entry is for PASSIVE
these routes are in a passive state, which is good
if they move to an ACTIVE state, it means the have lost their path in the network and looking for a replacement.
Each entry also shows the FEASIBLE DISTANCE, the next hop address, and the local egress interface
Corp#
show ip eigrp neighbors
IP-EIGRP neighbors for process 10
H Address Interface Hold Uptime SRTT RTO Q Seq
(sec) (ms) Cnt Num
0 10.1.5.2 Fa0/0 14 02:00:05 40 1000 0 19
1 10.1.3.2 Se0/0/1 13 01:59:59 40 1000 0 14
2 10.1.2.2 Se0/0/0 13 01:59:59 40 1000 0 13
3 10.1.4.2 Se0/1/0 12 01:59:57 40 1000 0 15
fields:
H - the order in which the neighbors were discovered
hold - how long the router will wait for a hello packet
uptime - how long the neigborship has been established
SRTT - smooth round trip timer - the time it takes for a round trip from this router, to neighbor, and back.
SRTT is used to determine how long to wait for a MULTICAST reply.
if a reply isnt received in time, the router switches to UNICASTS
RTO - Retransmission Time Out- is the time EIGRP waits before retransmitting a packet from the retransmission queue
Q - indicates wheter there are oustanding messages in the queue
Seq - indicates the sequence number of the last update from that neighbor. This is used to maintain syncrhonization and avoid duplicate
or out-of-sequence processing of messages
Corp#
show ip route eigrp
172.16.0.0/24 is subnetted, 1 subnets
D 172.16.10.0 [90/28160] via 10.1.5.2, 02:08:04, FastEthernet0/0
D 192.168.10.0/24 [90/2172416] via 10.1.3.2, 02:07:59, Serial0/0/1
[90/2172416] via 10.1.2.2, 02:07:59, Serial0/0/0
D 192.168.20.0/24 [90/2172416] via 10.1.3.2, 02:07:59, Serial0/0/1
[90/2172416] via 10.1.2.2, 02:07:59, Serial0/0/0
D 192.168.30.0/24 [90/2172416] via 10.1.4.2, 02:07:58, Serial0/1/0
D 192.168.40.0/24 [90/2172416] via 10.1.4.2, 02:07:58, Serial0/1/0
Corp#
show ip eigrp interfaces
IP-EIGRP interfaces for process 10
Xmit Queue Mean Pacing Time Multicast Pending
Interface Peers Un/Reliable SRTT Un/Reliable Flow Timer Routes
Vlan 0 0/0 1236 0/10 0 0
Fa0/0 1 0/0 1236 0/10 0 0
Se0/1/0 1 0/0 1236 0/10 0 0
Se0/0/1 1 0/0 1236 0/10 0 0
Se0/0/0 1 0/0 1236 0/10 0 0
Corp#
show ip protocols
Routing Protocol is "eigrp 10 "
Outgoing update filter list for all interfaces is not set
Incoming update filter list for all interfaces is not set
Default networks flagged in outgoing updates
Default networks accepted from incoming updates
Redistributing: eigrp 10
EIGRP-IPv4 Protocol for AS(10)
Metric weight K1=1, K2=0, K3=1, K4=0, K5=0 using K1 bandwidth and K2 delay by default
NSF-aware route hold timer is 240
Router-ID: 10.1.1.1
Topology : 0 (base)
Active Timer: 3 min
Distance: internal 90 external 170
Maximum path: 4
Maximum hopcount 100
Maximum metric variance 1
Automatic Summarization: disabled
Automatic address summarization:
Maximum path: 4
Routing for Networks:
10.0.0.0
Routing Information Sources:
Gateway Distance Last Update
10.1.5.2 90 0
10.1.3.2 90 8936
10.1.4.2 90 9511
10.1.2.2 90 9597
Distance: internal 90 external 170
Routing Protocol is "rip"
Sending updates every 30 seconds, next due in 13 seconds
Invalid after 180 seconds, hold down 180, flushed after 240
Outgoing update filter list for all interfaces is not set
Incoming update filter list for all interfaces is not set
Redistributing: rip
Default version control: send version 2, receive 2
Interface Send Recv Triggered RIP Key-chain
Vlan1 2 2
FastEthernet0/0 2 2
Serial0/0/1 2 2
Serial0/1/0 2 2
Serial0/0/0 2 2
Automatic network summarization is not in effect
Maximum path: 4
Routing for Networks:
10.0.0.0
Passive Interface(s):
Routing Information Sources:
Gateway Distance Last Update
10.1.5.2 120 00:00:05
10.1.3.2 120 00:00:12
10.1.2.2 120 00:00:12
10.1.4.2 120 00:00:17
Distance: (default is 120)
corp#
debug eigrp packet
break into two columns for readability
Observations:
There doesnt appear to be a pattern in the order each router is addressed, except that the TO's and FROM"s are grouped together
The TO messages dont show the destination IP, only the egress local interface
The FROM messages do show the remote IP, as well as the local ingress interface
Corp#
EIGRP: Received HELLO on FastEthernet0/0 nbr 10.1.5.2
AS 10, Flags 0x0, Seq 18/0 idbQ 0/0
hello from R3
Corp#
EIGRP: Received HELLO on Serial0/1/0 nbr 10.1.4.2
AS 10, Flags 0x0, Seq 16/0 idbQ 0/0
hello from R2
Corp#
EIGRP: Received HELLO on Serial0/0/0 nbr 10.1.2.2
AS 10, Flags 0x0, Seq 19/0 idbQ 0/0
hello from R1
------------------------------------------------------------
Corp#
EIGRP: Sending HELLO on Serial0/1/0
AS 10, Flags 0x0, Seq 21/0 idbQ 0/0 iidbQ un/rely 0/0
hello to R2
Corp#
EIGRP: Sending HELLO on FastEthernet0/0
AS 10, Flags 0x0, Seq 21/0 idbQ 0/0 iidbQ un/rely 0/0
hello to R3
Corp#
EIGRP: Sending HELLO on Serial0/0/1
AS 10, Flags 0x0, Seq 21/0 idbQ 0/0 iidbQ un/rely 0/0
hello to R1
Corp#
EIGRP: Sending HELLO on Serial0/0/0
AS 10, Flags 0x0, Seq 21/0 idbQ 0/0 iidbQ un/rely 0/0
hello to R1
Corp#
EIGRP: Sending HELLO on Vlan1
AS 10, Flags 0x0, Seq 21/0 idbQ 0/0 iidbQ un/rely 0/0
hello to switch card (not a router....)
------------------------------------------------------------
Corp#
EIGRP: Received HELLO on Serial0/0/1 nbr 10.1.3.2
AS 10, Flags 0x0, Seq 19/0 idbQ 0/0
hello from R1
Corp#
EIGRP: Received HELLO on FastEthernet0/0 nbr 10.1.5.2
AS 10, Flags 0x0, Seq 18/0 idbQ 0/0
hello from R3
Corp#
EIGRP: Received HELLO on Serial0/0/0 nbr 10.1.2.2
AS 10, Flags 0x0, Seq 19/0 idbQ 0/0
hello from R1
Corp#
EIGRP: Received HELLO on Serial0/1/0 nbr 10.1.4.2
AS 10, Flags 0x0, Seq 16/0 idbQ 0/0
hello from R2
------------------------------------------------------------
Corp#
EIGRP: Sending HELLO on Serial0/1/0
AS 10, Flags 0x0, Seq 21/0 idbQ 0/0 iidbQ un/rely 0/0
hello to R2... no neighbor IP?
Corp#
EIGRP: Sending HELLO on Serial0/0/0
AS 10, Flags 0x0, Seq 21/0 idbQ 0/0 iidbQ un/rely 0/0
hello to R1... no neighbor IP?
Corp#
EIGRP: Sending HELLO on FastEthernet0/0
AS 10, Flags 0x0, Seq 21/0 idbQ 0/0 iidbQ un/rely 0/0
hello to R3... no neighbor IP?
Corp#
EIGRP: Sending HELLO on Serial0/0/1
AS 10, Flags 0x0, Seq 21/0 idbQ 0/0 iidbQ un/rely 0/0
hello to R1
Corp#
EIGRP: Sending HELLO on Vlan1
AS 10, Flags 0x0, Seq 21/0 idbQ 0/0 iidbQ un/rely 0/0
hello to switch card (not a router)
------------------------------------------------------------
OUTPUT CONTINUES IN NEXT COLUMN
Corp#
EIGRP: Received HELLO on Serial0/0/1 nbr 10.1.3.2
AS 10, Flags 0x0, Seq 19/0 idbQ 0/0
hello from R1
Corp#
EIGRP: Received HELLO on FastEthernet0/0 nbr 10.1.5.2
AS 10, Flags 0x0, Seq 18/0 idbQ 0/0
hello from R3
Corp#
EIGRP: Received HELLO on Serial0/0/0 nbr 10.1.2.2
AS 10, Flags 0x0, Seq 19/0 idbQ 0/0
hello from R1
Corp#
EIGRP: Received HELLO on Serial0/1/0 nbr 10.1.4.2
AS 10, Flags 0x0, Seq 16/0 idbQ 0/0
hello from R2
------------------------------------------------------------
Corp#
EIGRP: Sending HELLO on Serial0/1/0
AS 10, Flags 0x0, Seq 21/0 idbQ 0/0 iidbQ un/rely 0/0
hello to R2
Corp#
EIGRP: Sending HELLO on Serial0/0/0
AS 10, Flags 0x0, Seq 21/0 idbQ 0/0 iidbQ un/rely 0/0
hello to R1
Corp#
EIGRP: Sending HELLO on Vlan1
AS 10, Flags 0x0, Seq 21/0 idbQ 0/0 iidbQ un/rely 0/0
hello to Corp switchcard
Corp#
EIGRP: Sending HELLO on Serial0/0/1
AS 10, Flags 0x0, Seq 21/0 idbQ 0/0 iidbQ un/rely 0/0
hello to R1
Corp#
EIGRP: Sending HELLO on FastEthernet0/0
AS 10, Flags 0x0, Seq 21/0 idbQ 0/0 iidbQ un/rely 0/0
hello to R3... no neighbor IP?
------------------------------------------------------------
Corp#
EIGRP: Received HELLO on Serial0/0/1 nbr 10.1.3.2
AS 10, Flags 0x0, Seq 19/0 idbQ 0/0
hello from R1
Corp#
EIGRP: Received HELLO on FastEthernet0/0 nbr 10.1.5.2
AS 10, Flags 0x0, Seq 18/0 idbQ 0/0
hello from R3
Corp#
EIGRP: Received HELLO on Serial0/1/0 nbr 10.1.4.2
AS 10, Flags 0x0, Seq 16/0 idbQ 0/0
hello from R2
Corp#
EIGRP: Received HELLO on Serial0/0/0 nbr 10.1.2.2
AS 10, Flags 0x0, Seq 19/0 idbQ 0/0
hello from R1
------------------------------------------------------------
Corp#
EIGRP: Sending HELLO on Serial0/1/0
AS 10, Flags 0x0, Seq 21/0 idbQ 0/0 iidbQ un/rely 0/0
hello to R2
Corp#
EIGRP: Sending HELLO on Vlan1
AS 10, Flags 0x0, Seq 21/0 idbQ 0/0 iidbQ un/rely 0/0
hello to Corp switchcard
EIGRP: Sending HELLO on Serial0/0/0
AS 10, Flags 0x0, Seq 21/0 idbQ 0/0 iidbQ un/rely 0/0
hello to R1
EIGRP: Sending HELLO on Serial0/0/1
AS 10, Flags 0x0, Seq 21/0 idbQ 0/0 iidbQ un/rely 0/0
hello to R1
Corp#
EIGRP: Sending HELLO on FastEthernet0/0
AS 10, Flags 0x0, Seq 21/0 idbQ 0/0 iidbQ un/rely 0/0
hello to R3
------------------------------------------------------------
Now some videos. To reinforce EIGRP concepts, and lead into OSPF
OSPF - OPEN SHORTEST PATH FIRST
Before enabling OSPF, we'll turn off RIP and EIGRP on all four routers.
Device(config)#
no router eigrp 10
Device(config)#
no router rip
The OSPF configs for the local egress ip address
Corp(config)#
router ospf 132
Corp(config)#
network 10.1.0.0 0.0.255.255 area 0
R1(config)#
router ospf 1
R1(config)#
network 10.1.0.0 0.0.255.255 area 0
R1(config)#
network 192.168.0.0 0.0.255.255 area 0
R2(config)#
router ospf 45678
R2(config)#
network 10.0.0.0 0.0.0.255 area 0
R2(config)#
network 192.168.30.1 0.0.0.0 area 0
R2(config)#
network 192.168.40.1 0.0.0.0 area 0
all 32 bits of the mask are specified for the 192 entries;
these are not network id's, they are HOST id's of the specific interfaces, which are EGRESS interfaces on the router we are configuring
R3(config)#
router ospf 1
R2(config)#
network 10.1.5.2 0.0.0.255 area 0
R2(config)#
network 172.16.10.0 0.0.0.255 area 0
Wildcard Masks
these notes are not intended to be a precise explanation of wlidcard masking, but rather a look into my thought process as I am learning the concept.
resources:
traceroute blog examples
routerjockey blog examples
subnetonline wildcard calculator
Ch 9 Exam Essentials
1. Know EIGRP features
classless (like RipV2 and OSPF)
distance vector
supports IP, IPX, appleTalk, IPV6
supports summaries and discontiguous networks
uses the Diffusing Update Algorithm (DUAL) to maintain route information
uses RTP to communicate with other EIGRP routers
uses the concept of an autonomous system to describe the set of contiguous routers that run the same routing protocol and share routing information
considered CLASSLESS- includes the subnet mask in its route updates
sends traditional distance-vector updates containing info about networks plus the cost of reaching them from the perspective of the advertising router
but not strictly distance-vector. Has link-state characteristics: synchronizes routing tables between neighbors at startup and then sends specific updates only when topology changes.
max hop count of 255 (default is 100)
but hop count is NOT a metric, like in RIP. Hop count is how many routers an EIGRP route update can traverse before being discarded. This limits the size of the AS.
2. Know how to configure EIGRP
the router eigrp [as] command turns EIGRP routing on in the router. Unlike RIPv1, EIGRP uses classless routing. BUT you can still configure as classful.
R1(config)#
router eigrp 10
enters router config mode
R1(config-router)#
network 10.0.0.0
on this router, interfaces that fall within 10.0.0.0 will advertise EIGRP info
3. Know how to verify EIGRP operation
Corp#
show ip
protocols
Corp#
show ip
route
Corp#
show ip
route eigrp
Corp#
show ip
eigrp neighbors
Corp#
show ip
eigrp topology
Corp#
show ip
eigrp interfaces
Corp#
show ip
protocols
info about all active routing protocols
Routing Protocol is "eigrp 10 "
Outgoing update filter list for all interfaces is not set
Incoming update filter list for all interfaces is not set
Default networks flagged in outgoing updates
Default networks accepted from incoming updates
Redistributing: eigrp 10
EIGRP-IPv4 Protocol for AS(10)
Metric weight K1=1, K2=0, K3=1, K4=0, K5=0
NSF-aware route hold timer is 240
Router-ID: 10.1.1.1
Topology : 0 (base)
Active Timer: 3 min
Distance: internal 90 external 170
Maximum path: 4
Maximum hopcount 100
Maximum metric variance 1
Automatic Summarization: disabled
Automatic address summarization:
Maximum path: 4
Routing for Networks:
10.0.0.0
Routing Information Sources:
Gateway Distance Last Update
10.1.2.2 90 200105
10.1.3.2 90 200113
10.1.4.2 90 254351
10.1.5.2 90 303742
Distance: internal 90 external 170
Corp#
show ip
protocols
(continued)
Routing Protocol is "rip"
Sending updates every 30 seconds, next due in 6 seconds
Invalid after 180 seconds, hold down 180, flushed after 240
Outgoing update filter list for all interfaces is not set
Incoming update filter list for all interfaces is not set
Redistributing: rip
Default version control: send version 2, receive 2
Interface Send Recv Triggered RIP Key-chain
Vlan1 2 2
FastEthernet0/0 2 2
Serial0/1/0 2 2
Serial0/0/1 2 2
Serial0/0/0 2 2
Automatic network summarization is not in effect
Maximum path: 4
Routing for Networks:
10.0.0.0
Passive Interface(s):
Routing Information Sources:
Gateway Distance Last Update
10.1.5.2 120 00:00:15
10.1.3.2 120 00:00:01
10.1.2.2 120 00:00:01
10.1.4.2 120 00:00:17
Distance: (default is 120)
Corp#
show ip
route
entire routing table
Codes: L - local, C - connected, S - static, R - RIP, M - mobile, B - BGP
D - EIGRP, EX - EIGRP external, O - OSPF, IA - OSPF inter area
N1 - OSPF NSSA external type 1, N2 - OSPF NSSA external type 2
E1 - OSPF external type 1, E2 - OSPF external type 2, E - EGP
i - IS-IS, L1 - IS-IS level-1, L2 - IS-IS level-2, ia - IS-IS inter area
* - candidate default, U - per-user static route, o - ODR
P - periodic downloaded static route
Gateway of last resort is not set
10.0.0.0/8 is variably subnetted, 10 subnets, 2 masks
C 10.1.1.0/24 is directly connected, Vlan1
L 10.1.1.1/32 is directly connected, Vlan1
C 10.1.2.0/24 is directly connected, Serial0/0/0
L 10.1.2.1/32 is directly connected, Serial0/0/0
C 10.1.3.0/24 is directly connected, Serial0/0/1
L 10.1.3.1/32 is directly connected, Serial0/0/1
C 10.1.4.0/24 is directly connected, Serial0/1/0
L 10.1.4.1/32 is directly connected, Serial0/1/0
C 10.1.5.0/24 is directly connected, FastEthernet0/0
L 10.1.5.1/32 is directly connected, FastEthernet0/0
172.16.0.0/16 is variably subnetted, 2 subnets, 2 masks
R 172.16.0.0/16 [120/1] via 10.1.5.2, 00:00:14, FastEthernet0/0
D 172.16.10.0/24 [90/28160] via 10.1.5.2, 00:07:23, FastEthernet0/0
D 192.168.10.0/24 [90/2172416] via 10.1.3.2, 00:09:13, Serial0/0/1
[90/2172416] via 10.1.2.2, 00:09:13, Serial0/0/0
D 192.168.20.0/24 [90/2172416] via 10.1.3.2, 00:09:13, Serial0/0/1
[90/2172416] via 10.1.2.2, 00:09:13, Serial0/0/0
D 192.168.30.0/24 [90/2172416] via 10.1.4.2, 00:08:59, Serial0/1/0
D 192.168.40.0/24 [90/2172416] via 10.1.4.2, 00:08:59, Serial0/1/0
Shows the entire routing table
Corp#
show ip
eigrp toplogy
all nets the Corp router can see, including on the other side of other routers
IP-EIGRP Topology Table for AS 10/ID(10.1.5.1)
Codes: P - Passive, A - Active, U - Update, Q - Query, R - Reply,
r - Reply status
directly connected via local egress interface
P 10.1.1.0/24, 1 successors, FD is 25625600
via Connected, Vlan1
P 10.1.2.0/24, 1 successors, FD is 2169856
via Connected, Serial0/0/0
P 10.1.3.0/24, 1 successors, FD is 2169856
via Connected, Serial0/0/1
P 10.1.4.0/24, 1 successors, FD is 2169856
via Connected, Serial0/1/0
P 10.1.5.0/24, 1 successors, FD is 28160
via Connected, FastEthernet0/0
remotely connected via remote ingress ip address
P 172.16.10.0/24, 1 successors, FD is 28160
via 10.1.5.2 (28160/25600), FastEthernet0/0
P 192.168.10.0/24, 2 successors, FD is 2172416
via 10.1.3.2 (2172416/28160), Serial0/0/1
via 10.1.2.2 (2172416/28160), Serial0/0/0
P 192.168.20.0/24, 2 successors, FD is 2172416
via 10.1.3.2 (2172416/28160), Serial0/0/1
via 10.1.2.2 (2172416/28160), Serial0/0/0
P 192.168.30.0/24, 1 successors, FD is 2172416
via 10.1.4.2 (2172416/28160), Serial0/1/0
P 192.168.40.0/24, 1 successors, FD is 2172416
via 10.1.4.2 (2172416/28160), Serial0/1/0
Corp#
show ip
eigrp interfaces
local interfaces on Corp, with peer data, 5 total, including VLAN1 (0 peers, no router on this network)
IP-EIGRP interfaces for process 10
Xmit Queue Mean Pacing Time Multicast Pending
Interface Peers Un/Reliable SRTT Un/Reliable Flow Timer Routes
Vlan 0 0/0 1236 0/10 0 0
Fa0/0 1 0/0 1236 0/10 0 0
Se0/0/1 1 0/0 1236 0/10 0 0
Se0/1/0 1 0/0 1236 0/10 0 0
Se0/0/0 1 0/0 1236 0/10 0 0
Corp#
show ip
eigrp neighbors
remote interfaces on the 4 neighboring routers
IP-EIGRP neighbors for process 10
H Address Interface Hold Uptime SRTT RTO Q Seq
(sec) (ms) Cnt Num
0 10.1.2.2 Se0/0/0 14 00:54:33 40 1000 0 58
1 10.1.3.2 Se0/0/1 10 00:54:33 40 1000 0 57
2 10.1.4.2 Se0/1/0 14 00:53:38 40 1000 0 51
3 10.1.5.2 Fa0/0 11 00:52:49 40 1000 0 33
4. Compare OSPF and RIPv1
RIPv1 is distance-vector and supports only classful routing. No VLSM
OSPF is link-state and supports VLSM and classless routing
5. Know how OSPF routers become neighboars and/or adjacent
they become neighbors when they see eachother's hello packets.
area id must match, links must be on the same subnet, hello/dead timers must be the same.
OSPF only shares routes with neigbors who have also established adjacencies. NOT ALL NEIGHBORS become adjacent.
When an OSPF router first receives a hello packet, it verifies that the data in some fields matches its own locally configured information.
Should any of the checked data be different, the hello packet is discarded and not processed. The data fields verified are the Area ID,
Authentication, Network Mask (on broadcast networks), Hello Interval, Router Dead Interval, and Options fields. If this information doesn’t match,
then neighborship is stuck in the down stage.
packetpushers.net
6. Be able to configure single-area OSPF
two commands:
router ospf [process id]
network x.x.x.x y.y.y.y area z
7. Be able to verify the operation of OSPF
Corp#
show ip
protocols
Corp#
show ip
route
Corp#
show ip
ospf
Corp#
show ip
ospf database
Corp#
show ip
ospf interface
Corp#
show ip
ospf neighbor
IOS 15.1
Corp#
show ip
protocols
Routing Protocol is "ospf 132"
Outgoing update filter list for all interfaces is not set
Incoming update filter list for all interfaces is not set
Router ID 10.1.5.1
Number of areas in this router is 1. 1 normal 0 stub 0 nssa
Maximum path: 4
Routing for Networks:
10.1.0.0 0.0.255.255 area 0
Routing Information Sources:
Gateway Distance Last Update
10.1.5.1 110 00:08:51
172.16.10.1 110 00:08:51
192.168.20.1 110 00:12:53
192.168.40.1 110 00:09:35
Distance: (default is 110)
IOS 15.1
Corp#
show ip
route
10.0.0.0/8 is variably subnetted, 10 subnets, 2 masks
C 10.1.1.0/24 is directly connected, Vlan1
L 10.1.1.1/32 is directly connected, Vlan1
C 10.1.2.0/24 is directly connected, Serial0/0/0
L 10.1.2.1/32 is directly connected, Serial0/0/0
C 10.1.3.0/24 is directly connected, Serial0/0/1
L 10.1.3.1/32 is directly connected, Serial0/0/1
C 10.1.4.0/24 is directly connected, Serial0/1/0
L 10.1.4.1/32 is directly connected, Serial0/1/0
C 10.1.5.0/24 is directly connected, FastEthernet0/0
L 10.1.5.1/32 is directly connected, FastEthernet0/0
172.16.0.0/24 is subnetted, 1 subnets
O 172.16.10.0/24 [110/10] via 10.1.5.2, 00:09:09, FastEthernet0/0
O 192.168.10.0/24 [110/65] via 10.1.2.2, 00:13:11, Serial0/0/0
O 192.168.20.0/24 [110/65] via 10.1.2.2, 00:13:01, Serial0/0/0
O 192.168.30.0/24 [110/65] via 10.1.4.2, 00:09:54, Serial0/1/0
O 192.168.40.0/24 [110/65] via 10.1.4.2, 00:09:54, Serial0/1/0
IOS 15.1
Corp#
show ip
ospf
Routing Process "ospf 132" with ID 10.1.5.1
Supports only single TOS(TOS0) routes
Supports opaque LSA
SPF schedule delay 5 secs, Hold time between two SPFs 10 secs
Minimum LSA interval 5 secs. Minimum LSA arrival 1 secs
Number of external LSA 0. Checksum Sum 0x000000
Number of opaque AS LSA 0. Checksum Sum 0x000000
Number of DCbitless external and opaque AS LSA 0
Number of DoNotAge external and opaque AS LSA 0
Number of areas in this router is 1. 1 normal 0 stub 0 nssa
External flood list length 0
Area BACKBONE(0)
Number of interfaces in this area is 5
Area has no authentication
SPF algorithm executed 7 times
Area ranges are
Number of LSA 5. Checksum Sum 0x034486
Number of opaque link LSA 0. Checksum Sum 0x000000
Number of DCbitless LSA 0
Number of indication LSA 0
Number of DoNotAge LSA 0
Flood list length 0
IOS 15.1
Corp#
show ip
ospf database
OSPF Router with ID (10.1.5.1) (Process ID 132)
Router Link States (Area 0)
Link ID ADV Router Age Seq# Checksum Link count
192.168.20.1 192.168.20.1 854 0x80000006 0x00ae08 6
192.168.40.1 192.168.40.1 656 0x80000004 0x006bc6 4
10.1.5.1 10.1.5.1 612 0x8000000f 0x00ab77 8
172.16.10.1 172.16.10.1 612 0x80000003 0x00b30d 2
Net Link States (Area 0)
Link ID ADV Router Age Seq# Checksum
10.1.5.1 10.1.5.1 612 0x80000001 0x00cc34
ADV Router aka RID/Router ID, the highest IP address on the router
we are seeing three connected routers + our own router (Corp at 10.1.5.1)
IOS 15.1
Corp#
show ip
ospf interface
Vlan1 is up, line protocol is up
Internet address is 10.1.1.1/24, Area 0
Process ID 132, Router ID 10.1.5.1, Network Type BROADCAST, Cost: 1
Transmit Delay is 1 sec, State DR, Priority 1
Designated Router (ID) 10.1.5.1, Interface address 10.1.1.1
No backup designated router on this network
Timer intervals configured, Hello 10, Dead 40, Wait 40, Retransmit 5
Hello due in 00:00:08
Index 1/1, flood queue length 0
Next 0x0(0)/0x0(0)
Last flood scan length is 1, maximum is 1
Last flood scan time is 0 msec, maximum is 0 msec
Neighbor Count is 0, Adjacent neighbor count is 0
Suppress hello for 0 neighbor(s)
FastEthernet0/0 is up, line protocol is up
Internet address is 10.1.5.1/24, Area 0
Process ID 132, Router ID 10.1.5.1, Network Type BROADCAST, Cost: 1
Transmit Delay is 1 sec, State DR, Priority 1
Designated Router (ID) 10.1.5.1, Interface address 10.1.5.1
Backup Designated Router (ID) 172.16.10.1, Interface address 10.1.5.2
Timer intervals configured, Hello 10, Dead 40, Wait 40, Retransmit 5
Hello due in 00:00:07
Index 2/2, flood queue length 0
Next 0x0(0)/0x0(0)
Last flood scan length is 1, maximum is 1
Last flood scan time is 0 msec, maximum is 0 msec
Neighbor Count is 1, Adjacent neighbor count is 1
Adjacent with neighbor 172.16.10.1 (Backup Designated Router)
Suppress hello for 0 neighbor(s)
Serial0/0/1 is up, line protocol is up
Internet address is 10.1.3.1/24, Area 0
Process ID 132, Router ID 10.1.5.1, Network Type POINT-TO-POINT, Cost: 64
Transmit Delay is 1 sec, State POINT-TO-POINT,
Timer intervals configured, Hello 10, Dead 40, Wait 40, Retransmit 5
Hello due in 00:00:07
Index 3/3, flood queue length 0
Next 0x0(0)/0x0(0)
Last flood scan length is 1, maximum is 1
Last flood scan time is 0 msec, maximum is 0 msec
Neighbor Count is 1 , Adjacent neighbor count is 1
Adjacent with neighbor 192.168.20.1
Suppress hello for 0 neighbor(s)
Serial0/1/0 is up, line protocol is up
Internet address is 10.1.4.1/24, Area 0
Process ID 132, Router ID 10.1.5.1, Network Type POINT-TO-POINT, Cost: 64
Transmit Delay is 1 sec, State POINT-TO-POINT,
Timer intervals configured, Hello 10, Dead 40, Wait 40, Retransmit 5
Hello due in 00:00:07
Index 4/4, flood queue length 0
Next 0x0(0)/0x0(0)
Last flood scan length is 1, maximum is 1
Last flood scan time is 0 msec, maximum is 0 msec
Neighbor Count is 1 , Adjacent neighbor count is 1
Adjacent with neighbor 192.168.40.1
Suppress hello for 0 neighbor(s)
Serial0/0/0 is up, line protocol is up
Internet address is 10.1.2.1/24, Area 0
Process ID 132, Router ID 10.1.5.1, Network Type POINT-TO-POINT, Cost: 64
Transmit Delay is 1 sec, State POINT-TO-POINT,
Timer intervals configured, Hello 10, Dead 40, Wait 40, Retransmit 5
Hello due in 00:00:07
Index 5/5, flood queue length 0
Next 0x0(0)/0x0(0)
Last flood scan length is 1, maximum is 1
Last flood scan time is 0 msec, maximum is 0 msec
Neighbor Count is 1 , Adjacent neighbor count is 1
Adjacent with neighbor 192.168.20.1
Suppress hello for 0 neighbor(s)
IOS 15.1
Corp#
show ip
ospf neighbor
Neighbor ID Pri State Dead Time Address Interface
192.168.20.1 0 FULL/ - 00:00:31 10.1.3.2 Serial0/0/1
192.168.40.1 0 FULL/ - 00:00:33 10.1.4.2 Serial0/1/0
192.168.20.1 0 FULL/ - 00:00:31 10.1.2.2 Serial0/0/0
172.16.10.1 1 FULL/BDR 00:00:32 10.1.5.2 FastEthernet0/0
Flashcards
Chapter 9 Written Lab 9.0
1. What four routed protocols are supported by EIGRP?
IPX, IPv4, IPv6, AppleTalk
2. When is redistribution required for EIGRP?
when there are multiple autonomous systems
redistribution is required when more than one EIGRP session or process is running and they are identified with different ASNs.
redistribution shares toplogy information between EIGRP sessions
3. What command would be used to enable EIGRP with an autonmous system number of 300?
router eigrp 300
4. What command will tell EIGRP that it is connected to network 172.10.0.0?
network 172.10.0.0
5. What type of EIGRP interface will neither send nor receive Hello packets?
passive-interface s0/0
6. Write the command that will enable OSPF process 101 on a router
router ospf 101
7. Write the command that will display details of all OSFP routing processes enabled on a router
show ip ospf
8. Write the command that will display interface-specific OSPF information
show ip ospf interface
9. Write the command that will display all OSPF neighbors
show ip ospf neighbor
10. Write the command that will display all different OSPF route types that are currently known by the router
show ip route ospf
Chapter 9 Hands-On Labs
Build the network and configure interfaces
LabA(config)#
int f0/0
LabA(config-if)#
ip addr 172.16.10.1 255.255.255.0
LabA(config-if)#
no shut
LabB(config)#
int f0/0
LabB(config-if)#
ip addr 172.16.10.2 255.255.255.0
LabB(config-if)#
no shut
LabB(config-if)#
int s0/0/0
LabB(config-if)#
ip addr 172.16.20.1 255.255.255.0
LabB(config-if)#
no shut
LabC(config)#
int f0/0
LabC(config-if)#
ip addr 172.16.30.1 255.255.255.0
LabC(config-if)#
no shut
LabC(config-if)#
int s0/0/0
LabC(config-if)#
ip addr 172.16.20.2 255.255.255.0
LabC(config-if)#
no shut
LabC(config-if)#
int s0/0/1
LabC(config-if)#
ip addr 172.16.40.1 255.255.255.0
LabC(config-if)#
no shut
LabD(config)#
int s0/0/0
LabD(config-if)#
ip addr 172.16.40.2 255.255.255.0
LabD(config-if)#
no shut
LabD(config-if)#
int f0/0
LabD(config-if)#
ip addr 172.16.50.1 255.255.255.0
LabD(config-if)#
no shut
9.1 - Configure and Verfiy EIGRP
configure EIGRP on all 4 routers and observe results
LabA
LabA(config)#
router eigrp 100
LabA(config-router)#
net 172.16.0.0
[no output]
LabA#
show ip eigrp neighbors
IP-EIGRP neighbors for process 100
LabA#
show ip eigrp topology
IP-EIGRP Topology Table for AS 100/ID(172.16.10.1)
Codes: P - Passive, A - Active, U - Update, Q - Query, R - Reply,
r - Reply status
P 172.16.10.0/24, 1 successors, FD is 28160
via Connected, FastEthernet0/0
LabA#
show ip eigrp interfaces
IP-EIGRP interfaces for process 100
Xmit Queue Mean Pacing Time Multicast Pending
Interface Peers Un/Reliable SRTT Un/Reliable Flow Timer Routes
Fa0/0 0 0/0 1236 0/10 0 0
no neighbors at this point since EIGRP is only active on this router. One successor AKA route, which is the connection out of this router.
But note that we have no information about what's on the other side of that link
LabB
LabB(config)#
router eigrp 100
LabB(config-router)#
net 172.16.0.0
%DUAL-5-NBRCHANGE: IP-EIGRP 100:
Neighbor 172.16.10.1 (FastEthernet0/0) is up: new adjacency
LabB#
show ip eigrp neighbors
IP-EIGRP neighbors for process 100
H Address Interface Hold Uptime SRTT RTO Q Seq
(sec) (ms) Cnt Num
0 172.16.10.1 Fa0/0 12 00:00:14 40 1000 0 1
LabB#
show ip eigrp topology
IP-EIGRP Topology Table for AS 100/ID(172.16.20.1)
Codes: P - Passive, A - Active, U - Update, Q - Query, R - Reply,
r - Reply status
P 172.16.10.0/24, 1 successors, FD is 28160
via Connected, FastEthernet0/0
P 172.16.20.0/24, 1 successors, FD is 2169856
via Connected, Serial0/0/0
LabB#
show ip eigrp interfaces
IP-EIGRP interfaces for process 100
Xmit Queue Mean Pacing Time Multicast Pending
Interface Peers Un/Reliable SRTT Un/Reliable Flow Timer Routes
Fa0/0 1 0/0 1236 0/10 0 0
Se0/0/0 0 0/0 1236 0/10 0 0
We can see a neighbor at .1
We now have two paths out of this router. Left to neighbor. Exit at right is available as successor(route), but again we have no info about
what is on the other side, since that router has no EIGRP yet (s0/0/0 has no peers, but is an EIGRP interface)
LabC
LabC(config)#
router eigrp 100
LabC(config-router)#
net 172.16.0.0
%DUAL-5-NBRCHANGE: IP-EIGRP 100:
Neighbor 172.16.20.1 (Serial0/0/0) is up: new adjacency
LabC#
show ip eigrp neighbors
IP-EIGRP neighbors for process 100
H Address Interface Hold Uptime SRTT RTO Q Seq
(sec) (ms) Cnt Num
0 172.16.20.1 Se0/0/0 12 00:00:25 40 1000 0 8
LabC#
show ip eigrp toplogy
IP-EIGRP Topology Table for AS 100/ID(172.16.40.1)
Codes: P - Passive, A - Active, U - Update, Q - Query, R - Reply,
r - Reply status
P 172.16.10.0/24, 1 successors, FD is 2172416
via 172.16.20.1 (2172416/28160), Serial0/0/0
P 172.16.20.0/24, 1 successors, FD is 2169856
via Connected, Serial0/0/0
P 172.16.30.0/24, 1 successors, FD is 28160
via Connected, FastEthernet0/0
P 172.16.40.0/24, 1 successors, FD is 2169856
via Connected, Serial0/0/1
LabC#
show ip eigrp interfaces
IP-EIGRP interfaces for process 100
Xmit Queue Mean Pacing Time Multicast Pending
Interface Peers Un/Reliable SRTT Un/Reliable Flow Timer Routes
Fa0/0 0 0/0 1236 0/10 0 0
Se0/0/0 1 0/0 1236 0/10 0 0
Se0/0/1 0 0/0 1236 0/10 0 0
.1 router B interface is now a neighbor.
LabC topology shows the 3 direct connected networks AND the network on the other side of LabB since LabB is our EIGRP neighbor
3 eigrp interfaces:
Fa0/0 is ours at LabC- no peers bc there is no eigrp router on the other end
s0/0/0 is our interface out left to LabB which is an EIGRP peer
s0/0/1 is our interface out right which does not see an EIGRP peer but does put that net 172.16.40.0 in our topology
LabD
LabD(config)#
router eigrp 100
LabD(config-router)#
net 172.16.0.0
%DUAL-5-NBRCHANGE: IP-EIGRP 100:
Neighbor 172.16.40.1 (Serial0/0/0) is up: new adjacency
LabD#
show ip eigrp neighbors
IP-EIGRP neighbors for process 100
H Address Interface Hold Uptime SRTT RTO Q Seq
(sec) (ms) Cnt Num
0 172.16.40.1 Se0/0/0 11 00:00:14 40 1000 0 6
LabD#
show ip eigrp topology
IP-EIGRP Topology Table for AS 100/ID(172.16.50.1)
Codes: P - Passive, A - Active, U - Update, Q - Query, R - Reply,
r - Reply status
P 172.16.10.0/24, 1 successors, FD is 2684416
via 172.16.40.1 (2684416/2172416), Serial0/0/0
P 172.16.20.0/24, 1 successors, FD is 2681856
via 172.16.40.1 (2681856/2169856), Serial0/0/0
P 172.16.30.0/24, 1 successors, FD is 2172416
via 172.16.40.1 (2172416/28160), Serial0/0/0
P 172.16.40.0/24, 1 successors, FD is 2169856
via Connected, Serial0/0/0
P 172.16.50.0/24, 1 successors, FD is 28160
via Connected, FastEthernet0/0
LabD#
show ip eigrp interfaces
IP-EIGRP interfaces for process 100
Xmit Queue Mean Pacing Time Multicast Pending
Interface Peers Un/Reliable SRTT Un/Reliable Flow Timer Routes
Fa0/0 0 0/0 1236 0/10 0 0
Se0/0/0 1 0/0 1236 0/10 0 0
LabC to our left is now a neighbor at 172.16.40.1
toplogy shows a route out to the right (no router on that end)
a route to the left to LabC .40.0
the .10.0, .20.0, and .30.0 networks via info from LabC
2 eigrp interfaces-
fa0/0 out to the right
s0/0/0 out left to LabC
Time to remove EIGRP from all four routers to prepare for the OSPF lab next,
since EIGRP has a lower AD than OSPF
LabA(config)#
no router eigrp 100
LabB(config)#
no router eigrp 100
LabC(config)#
no router eigrp 100
LabD(config)#
no router eigrp 100
9.2 - Enabling the OSPF Process
9.3 - Configuring OSPF Interfaces
9.4 - Verifying OSPF Operation
LabA
LabA(config)#
router ospf 100
LabA(config-router)#
net 172.16.10.1 0.0.0.0 area 0
[no output]
LabA#
show ip ospf neighbor
[no output]
LabA#
show ip ospf database
OSPF Router with ID (172.16.10.1) (Process ID 100)
Router Link States (Area 0)
Link ID ADV Router Age Seq# Checksum Link count
172.16.10.1 172.16.10.1 44 0x80000001 0x00b24b 1
LabA#
show ip ospf interface
FastEthernet0/0 is up, line protocol is up
Internet address is 172.16.10.1/24, Area 0
Process ID 100, Router ID 172.16.10.1, Network Type BROADCAST, Cost: 1
Transmit Delay is 1 sec, State DR, Priority 1
Designated Router (ID) 172.16.10.1, Interface address 172.16.10.1
No backup designated router on this network
Timer intervals configured, Hello 10, Dead 40, Wait 40, Retransmit 5
Hello due in 00:00:08
Index 1/1, flood queue length 0
Next 0x0(0)/0x0(0)
Last flood scan length is 1, maximum is 1
Last flood scan time is 0 msec, maximum is 0 msec
Neighbor Count is 0, Adjacent neighbor count is 0
Suppress hello for 0 neighbor(s)
we're including this router's interface 172.16.10.1 in our ospf area 0
fa0/0 now registers as an ospf interface
the ospf database includes data about this link only.... LabA is counting itself(10.1) as ADVERTISTING router?
the designated router is .1 LabA
LabB
LabB(config)#
router ospf 101
LabB(config-router)#
net 172.16.10.2 0.0.0.0 area 0
LabB(config-router)#
net 172.16.20.1 0.0.0.0 area 0
01:26:36: %OSPF-5-ADJCHG: Process 101, Nbr 172.16.10.1
on FastEthernet0/0 from LOADING to FULL, Loading Done
LabB#
show ip ospf neighbor
Neighbor ID Pri State Dead Time Address Interface
172.16.10.1 1 FULL/DR 00:00:33 172.16.10.1
LabB#
show ip ospf database
OSPF Router with ID (172.16.20.1) (Process ID 101)
Router Link States (Area 0)
Link ID ADV Router Age Seq# Checksum Link count
172.16.10.1 172.16.10.1 145 0x80000002 0x0067cd 1
172.16.20.1 172.16.20.1 32 0x80000003 0x006e8f 2
Net Link States (Area 0)
Link ID ADV Router Age Seq# Checksum
172.16.10.1 172.16.10.1 145 0x80000001 0x00953d
LabB#
show ip ospf interface
FastEthernet0/0 is up, line protocol is up
Internet address is 172.16.10.2/24, Area 0
Process ID 101, Router ID 172.16.20.1, Network Type BROADCAST, Cost: 1
Transmit Delay is 1 sec, State BDR, Priority 1
Designated Router (ID) 172.16.10.1, Interface address 172.16.10.1
Backup Designated Router (ID) 172.16.20.1, Interface address 172.16.10.2
Timer intervals configured, Hello 10, Dead 40, Wait 40, Retransmit 5
Hello due in 00:00:03
Index 1/1, flood queue length 0
Next 0x0(0)/0x0(0)
Last flood scan length is 1, maximum is 1
Last flood scan time is 0 msec, maximum is 0 msec
Neighbor Count is 1, Adjacent neighbor count is 1
Adjacent with neighbor 172.16.10.1 (Designated Router)
Suppress hello for 0 neighbor(s)
Serial0/0/0 is up, line protocol is up
Internet address is 172.16.20.1/24, Area 0
Process ID 101, Router ID 172.16.20.1, Network Type POINT-TO-POINT, Cost: 64
Transmit Delay is 1 sec, State POINT-TO-POINT,
Timer intervals configured, Hello 10, Dead 40, Wait 40, Retransmit 5
Hello due in 00:00:04
Index 2/2, flood queue length 0
Next 0x0(0)/0x0(0)
Last flood scan length is 1, maximum is 1
Last flood scan time is 0 msec, maximum is 0 msec
Suppress hello for 0 neighbor(s)
We've include the two interfaces on this router in the OSPF area
and can now see Router A's interface 10.1 to the left as a neighbor in the area
the "OSPF Database" now shows two links 20.1(local) and 10.1(neighbor) as 'router link states'.
"ADV Router" means advertising router for the two links. The link address is used as the advertising router.
database shows "Net Link States" category with one entry- 172.16.10.1 which is the address of neighbor router to our left
we have two local OSPF interfaces- f0/0 and s0/0/0
LabC
LabC(config)#
router ospf 102
LabC(config-router)#
net 172.16.20.2 0.0.0.0 area 0
LabC(config-router)#
net 172.16.30.1 0.0.0.0 area 0
LabC(config-router)#
net 172.16.40.1 0.0.0.0 area 0
01:33:54: %OSPF-5-ADJCHG: Process 102, Nbr 172.16.20.1
on Serial0/0/0 from LOADING to FULL, Loading Done
LabC#
show ip ospf neighbor
Neighbor ID Pri State Dead Time Address Interface
172.16.20.1 0 FULL/ - 00:00:30 172.16.20.1 Serial0/0/0
LabC#
show ip ospf database
OSPF Router with ID (172.16.40.1) (Process ID 102)
Router Link States (Area 0)
Link ID ADV Router Age Seq# Checksum Link count
172.16.10.1 172.16.10.1 542 0x80000002 0x0067cd 1
172.16.20.1 172.16.20.1 90 0x80000004 0x00a551 3
172.16.40.1 172.16.40.1 37 0x80000004 0x00e47c 4
Net Link States (Area 0)
Link ID ADV Router Age Seq# Checksum
172.16.10.1 172.16.10.1 542 0x80000001 0x00953d
LabC#
show ip ospf interface
Serial0/0/0 is up, line protocol is up
Internet address is 172.16.20.2/24, Area 0
Process ID 102, Router ID 172.16.40.1, Network Type POINT-TO-POINT, Cost: 64
Transmit Delay is 1 sec, State POINT-TO-POINT,
Timer intervals configured, Hello 10, Dead 40, Wait 40, Retransmit 5
Hello due in 00:00:01
Index 1/1, flood queue length 0
Next 0x0(0)/0x0(0)
Last flood scan length is 1, maximum is 1
Last flood scan time is 0 msec, maximum is 0 msec
Neighbor Count is 1 , Adjacent neighbor count is 1
Adjacent with neighbor 172.16.20.1
Suppress hello for 0 neighbor(s)
FastEthernet0/0 is up, line protocol is up
Internet address is 172.16.30.1/24, Area 0
Process ID 102, Router ID 172.16.40.1, Network Type BROADCAST, Cost: 1
Transmit Delay is 1 sec, State DR, Priority 1
Designated Router (ID) 172.16.40.1, Interface address 172.16.30.1
No backup designated router on this network
Timer intervals configured, Hello 10, Dead 40, Wait 40, Retransmit 5
Hello due in 00:00:02
Index 2/2, flood queue length 0
Next 0x0(0)/0x0(0)
Last flood scan length is 1, maximum is 1
Last flood scan time is 0 msec, maximum is 0 msec
Neighbor Count is 0, Adjacent neighbor count is 0
Suppress hello for 0 neighbor(s)
Serial0/0/1 is up, line protocol is up
Internet address is 172.16.40.1/24, Area 0
Process ID 102, Router ID 172.16.40.1, Network Type POINT-TO-POINT, Cost: 64
Transmit Delay is 1 sec, State POINT-TO-POINT,
Timer intervals configured, Hello 10, Dead 40, Wait 40, Retransmit 5
Hello due in 00:00:08
Index 3/3, flood queue length 0
Next 0x0(0)/0x0(0)
Last flood scan length is 1, maximum is 1
Last flood scan time is 0 msec, maximum is 0 msec
Suppress hello for 0 neighbor(s)
we include the three nets conneted to labC in the area.. 20.0, 30.0, and 40.0
link to our left, 20.1 is visible as "Neighbor"
OSPF Database-
Router Link States are
10.1(Router A)
20.1(Router B)
40.1(Router C)(This router)
Net Link States
10.1(Router A)... why does only Router A show here?
Reference- router link state vs net link state
Router Link States are type 1 LSAs. It lists all the routers in the area and the number of interfaces. 40.1 has 4 interfaces
Net Link States are the multi-access networks (Type 2 LSAs). The ADV (advertising router) is the DR.
LabD
LabD(config)#
router ospf 103
LabD(config-router)#
net 172.16.40.2 0.0.0.0 area 0
LabD(config-router)#
net 172.16.50.1 0.0.0.0 area 0
01:37:11: %OSPF-5-ADJCHG: Process 103, Nbr 172.16.40.1
on Serial0/0/0 from LOADING to FULL, Loading Done
LabD#
show ip ospf neighbor
Neighbor ID Pri State Dead Time Address Interface
172.16.40.1 0 FULL/ - 00:00:32 172.16.40.1 Serial0/0/0
LabD#
show ip ospf database
OSPF Router with ID (172.16.50.1) (Process ID 103)
Router Link States (Area 0)
Link ID ADV Router Age Seq# Checksum Link count
172.16.10.1 172.16.10.1 785 0x80000002 0x0067cd 1
172.16.20.1 172.16.20.1 333 0x80000004 0x00a551 3
172.16.40.1 172.16.40.1 111 0x80000005 0x00013b 5
172.16.50.1 172.16.50.1 53 0x80000003 0x001023 3
Net Link States (Area 0)
Link ID ADV Router Age Seq# Checksum
172.16.10.1 172.16.10.1 785 0x80000001 0x00953d
LabD#
show ip ospf interface
Serial0/0/0 is up, line protocol is up
Internet address is 172.16.40.2/24, Area 0
Process ID 103, Router ID 172.16.50.1, Network Type POINT-TO-POINT, Cost: 64
Transmit Delay is 1 sec, State POINT-TO-POINT,
Timer intervals configured, Hello 10, Dead 40, Wait 40, Retransmit 5
Hello due in 00:00:01
Index 1/1, flood queue length 0
Next 0x0(0)/0x0(0)
Last flood scan length is 1, maximum is 1
Last flood scan time is 0 msec, maximum is 0 msec
Neighbor Count is 1 , Adjacent neighbor count is 1
Adjacent with neighbor 172.16.40.1
Suppress hello for 0 neighbor(s)
FastEthernet0/0 is up, line protocol is up
Internet address is 172.16.50.1/24, Area 0
Process ID 103, Router ID 172.16.50.1, Network Type BROADCAST, Cost: 1
Transmit Delay is 1 sec, State WAITING, Priority 1
No designated router on this network
No backup designated router on this network
Timer intervals configured, Hello 10, Dead 40, Wait 40, Retransmit 5
Hello due in 00:00:04
Index 2/2, flood queue length 0
Next 0x0(0)/0x0(0)
Last flood scan length is 1, maximum is 1
Last flood scan time is 0 msec, maximum is 0 msec
Neighbor Count is 0, Adjacent neighbor count is 0
Suppress hello for 0 neighbor(s)
observations
the OSPF databases now match across all 4 routers.
NOTE that this is a database of routers, identified by
router ID. It is not a topology that lists routers AND routes,
like in the "equivalent" eigrp command.show eigrp topology
----------------------------------------------------------------------------------
PAUSE- a tale of a misconfigured network
After a 9 month hiatus, I am reviewing this book and have made it back to Chapter 9. I'm studing this webpage, working thorough the OSPF configurations
described above, and I get stuck on the concept of "link count" under "Router Link States" found in the output of show ip ospf database
The structure of the notes above is helpful, because I was tracking the state of each router BEFORE i made changes to the subsquent router. But just to be sure,
today I decided to recreate the topology, then configure each router one at a time, noting the results as I went.
And I ran into some problems.
Here is the original topology:
And today's recreated toplogy:
After replicating the toplogy and programming the IP addresses on each router, I started on configurations, just like before:
LabA
LabA(config)#
router ospf 100
LabA(config-router)#
net 172.16.10.1 0.0.0.0 area 0
[no output]
LabA#
show ip ospf neighbor
[no output]
LabA#
show ip ospf database
OSPF Router with ID (172.16.10.1) (Process ID 100)
Router Link States (Area 0)
Link ID ADV Router Age Seq# Checksum Link count
172.16.10.1 172.16.10.1 44 0x80000001 0x00b24b 1
LabA#
show ip ospf interface
FastEthernet0/0 is up, line protocol is up
Internet address is 172.16.10.1/24, Area 0
Process ID 100, Router ID 172.16.10.1, Network Type BROADCAST, Cost: 1
Transmit Delay is 1 sec, State DR, Priority 1
Designated Router (ID) 172.16.10.1, Interface address 172.16.10.1
No backup designated router on this network
Timer intervals configured, Hello 10, Dead 40, Wait 40, Retransmit 5
Hello due in 00:00:08
Index 1/1, flood queue length 0
Next 0x0(0)/0x0(0)
Last flood scan length is 1, maximum is 1
Last flood scan time is 0 msec, maximum is 0 msec
Neighbor Count is 0, Adjacent neighbor count is 0
Suppress hello for 0 neighbor(s)
good so far.... On to LabB router
LabB
LabB(config)#
router ospf 101
LabB(config-router)#
net 172.16.10.2 0.0.0.0 area 0
LabB(config-router)#
net 172.16.20.1 0.0.0.0 area 0
01:26:36: %OSPF-5-ADJCHG: Process 101, Nbr 172.16.10.1
on FastEthernet0/0 from LOADING to FULL, Loading Done
LabB#
show ip ospf neighbor
Neighbor ID Pri State Dead Time Address Interface
172.16.10.1 1 FULL/DR 00:00:33 172.16.10.1
LabB#
show ip ospf database
OSPF Router with ID (172.16.20.1) (Process ID 101)
Router Link States (Area 0)
Link ID ADV Router Age Seq# Checksum Link count
172.16.10.1 172.16.10.1 145 0x80000002 0x0067cd 1
172.16.20.1 172.16.20.1 32 0x80000003 0x006e8f 2
Net Link States (Area 0)
Link ID ADV Router Age Seq# Checksum
172.16.10.1 172.16.10.1 145 0x80000001 0x00953d
LabB#
show ip ospf interface
FastEthernet0/0 is up, line protocol is up
Internet address is 172.16.10.2/24, Area 0
Process ID 101, Router ID 172.16.20.1, Network Type BROADCAST, Cost: 1
Transmit Delay is 1 sec, State BDR, Priority 1
Designated Router (ID) 172.16.10.1, Interface address 172.16.10.1
Backup Designated Router (ID) 172.16.20.1, Interface address 172.16.10.2
Timer intervals configured, Hello 10, Dead 40, Wait 40, Retransmit 5
Hello due in 00:00:03
Index 1/1, flood queue length 0
Next 0x0(0)/0x0(0)
Last flood scan length is 1, maximum is 1
Last flood scan time is 0 msec, maximum is 0 msec
Neighbor Count is 1, Adjacent neighbor count is 1
Adjacent with neighbor 172.16.10.1 (Designated Router)
Suppress hello for 0 neighbor(s)
Serial0/0/0 is up, line protocol is up
Internet address is 172.16.20.1/24, Area 0
Process ID 101, Router ID 172.16.20.1, Network Type POINT-TO-POINT, Cost: 64
Transmit Delay is 1 sec, State POINT-TO-POINT,
Timer intervals configured, Hello 10, Dead 40, Wait 40, Retransmit 5
Hello due in 00:00:04
Index 2/2, flood queue length 0
Next 0x0(0)/0x0(0)
Last flood scan length is 1, maximum is 1
Last flood scan time is 0 msec, maximum is 0 msec
Suppress hello for 0 neighbor(s)
still looks good; same as before.... On to LabC router
LabC
LabC(config)#
router ospf 102
LabC(config-router)#
net 172.16.20.2 0.0.0.0 area 0
LabC(config-router)#
net 172.16.30.1 0.0.0.0 area 0
LabC(config-router)#
net 172.16.40.1 0.0.0.0 area 0
01:33:54: %OSPF-5-ADJCHG: Process 102, Nbr 172.16.20.1
on Serial0/0/0 from LOADING to FULL, Loading Done
LabC#
show ip ospf neighbor
[no output]
And here is where I ran into trouble. The show ip ospf neighbor command returns nothing. How can
that be?
After awhile I realized it is due to a misconfiguration in the topology.
For Lab C, I programmed the interfaces as follows:
LabC(config)#
int f0/0
LabC(config-if)#
ip addr 172.16.30.1 255.255.255.0
LabC(config-if)#
no shut
LabC(config-if)#
int s0/0/0
LabC(config-if)#
ip addr 172.16.20.2 255.255.255.0
LabC(config-if)#
no shut
LabC(config-if)#
int s0/0/1
LabC(config-if)#
ip addr 172.16.40.1 255.255.255.0
LabC(config-if)#
no shut
and again here is the topology for that router:
but here is what it SHOULD HAVE looked like (as it did the first time I built it)
S0/0/0 and S0/0/1 are swapped. When I gave the IP 172.16.20.2 to s/0/0/0, thinking that was the interface on the left side
which faces Lab B, I was actually giving 172.16.20.2 to the right side, facing LabC (which has no OSPF configs yet.)
Since the left side got got the IP intended for the right side which was 172.16.40.1
the inverse also occured-
the right side got the IP intended for the left which was 172.16.20.2
LabC left side should have been
s0/0/0 with 20.2
and LabC right side should have been
s0/0/1 with 40.1
The correct IPs were mapped to the correct interfaces. But the mistake happened before I even programmed them.
When I made the connections from LabB to LabC and from LabD to LabC, I plugged then into the wrong ports.
Interestingly.. not only is this causing OSPF to not see B as a neighbor from C.. but B and C cannot ping eachother either.
@B the config is 172.16.20.1/24 @ S0/0/0
@C the config is 172.16.40.1/24 @ S/0/0/1
meaning they are not even on the same network! But the system is not throwing any errors or bringing it to my attention.
It just fails to connect.
To correct the issue, I simply deleted those two links and re-created them. Worth noting, I used the auto select cable here,
which does not ask which interface you want to use when attaching. Earlier I must have plugged the right side first, and
auto select plugged into 0/0/0.
This time I plugged into left side first.
Now LabC OSPF data is reading out correctly...
LabC
LabC(config)#
router ospf 102
LabC(config-router)#
net 172.16.20.2 0.0.0.0 area 0
LabC(config-router)#
net 172.16.30.1 0.0.0.0 area 0
LabC(config-router)#
net 172.16.40.1 0.0.0.0 area 0
01:33:54: %OSPF-5-ADJCHG: Process 102, Nbr 172.16.20.1
on Serial0/0/0 from LOADING to FULL, Loading Done
LabC#
show ip ospf neighbor
Neighbor ID Pri State Dead Time Address Interface
172.16.20.1 0 FULL/ - 00:00:30 172.16.20.1 Serial0/0/0
LabC#
show ip ospf database
OSPF Router with ID (172.16.40.1) (Process ID 102)
Router Link States (Area 0)
Link ID ADV Router Age Seq# Checksum Link count
172.16.10.1 172.16.10.1 542 0x80000002 0x0067cd 1
172.16.20.1 172.16.20.1 90 0x80000004 0x00a551 3
172.16.40.1 172.16.40.1 37 0x80000004 0x00e47c 4
Net Link States (Area 0)
Link ID ADV Router Age Seq# Checksum
172.16.10.1 172.16.10.1 542 0x80000001 0x00953d
LabC#
show ip ospf interface
Serial0/0/0 is up, line protocol is up
Internet address is 172.16.20.2/24, Area 0
Process ID 102, Router ID 172.16.40.1, Network Type POINT-TO-POINT, Cost: 64
Transmit Delay is 1 sec, State POINT-TO-POINT,
Timer intervals configured, Hello 10, Dead 40, Wait 40, Retransmit 5
Hello due in 00:00:01
Index 1/1, flood queue length 0
Next 0x0(0)/0x0(0)
Last flood scan length is 1, maximum is 1
Last flood scan time is 0 msec, maximum is 0 msec
Neighbor Count is 1 , Adjacent neighbor count is 1
Adjacent with neighbor 172.16.20.1
Suppress hello for 0 neighbor(s)
FastEthernet0/0 is up, line protocol is up
Internet address is 172.16.30.1/24, Area 0
Process ID 102, Router ID 172.16.40.1, Network Type BROADCAST, Cost: 1
Transmit Delay is 1 sec, State DR, Priority 1
Designated Router (ID) 172.16.40.1, Interface address 172.16.30.1
No backup designated router on this network
Timer intervals configured, Hello 10, Dead 40, Wait 40, Retransmit 5
Hello due in 00:00:02
Index 2/2, flood queue length 0
Next 0x0(0)/0x0(0)
Last flood scan length is 1, maximum is 1
Last flood scan time is 0 msec, maximum is 0 msec
Neighbor Count is 0, Adjacent neighbor count is 0
Suppress hello for 0 neighbor(s)
Serial0/0/1 is up, line protocol is up
Internet address is 172.16.40.1/24, Area 0
Process ID 102, Router ID 172.16.40.1, Network Type POINT-TO-POINT, Cost: 64
Transmit Delay is 1 sec, State POINT-TO-POINT,
Timer intervals configured, Hello 10, Dead 40, Wait 40, Retransmit 5
Hello due in 00:00:08
Index 3/3, flood queue length 0
Next 0x0(0)/0x0(0)
Last flood scan length is 1, maximum is 1
Last flood scan time is 0 msec, maximum is 0 msec
Suppress hello for 0 neighbor(s)
Which brings me to the original reason I re-created this topology... I was confused about the LINK COUNTS
here:
OSPF Router with ID (172.16.40.1) (Process ID 102)
Router Link States (Area 0)
Link ID ADV Router Age Seq# Checksum Link count
172.16.10.1 172.16.10.1 542 0x80000002 0x0067cd 1
172.16.20.1 172.16.20.1 90 0x80000004 0x00a551 3
172.16.40.1 172.16.40.1 37 0x80000004 0x00e47c 4
Net Link States (Area 0)
Link ID ADV Router Age Seq# Checksum
172.16.10.1 172.16.10.1 542 0x80000001 0x00953d
The steps of recreating the lab were helpful, but this link answered the question:
Here is the output of each router's command show ip ospf interface as they are
set up one at a time.
LabA - No OSPF at B, C, or D yet
show ip ospf database
OSPF Router with ID (172.16.10.1) (Process ID 100)
Router Link States (Area 0)
Link ID ADV Router Age Seq# Checksum Link count
172.16.10.1 172.16.10.1 44 0x80000001 0x00b24b 1
LabB - No OSPF at C or D yet
show ip ospf database
OSPF Router with ID (172.16.20.1) (Process ID 101)
Router Link States (Area 0)
Link ID ADV Router Age Seq# Checksum Link count
172.16.10.1 172.16.10.1 145 0x80000002 0x0067cd 1
172.16.20.1 172.16.20.1 32 0x80000003 0x006e8f 2
Net Link States (Area 0)
Link ID ADV Router Age Seq# Checksum
172.16.10.1 172.16.10.1 145 0x80000001 0x00953d
the 20.2 interface on this router has 2 ospf links.
The left-facing out to RA, a crossover cable
The right-facing out to RC, a serial cable.
If the solution I found is correct, why is this serial link not being counted twice? The solution (I think)
is revealed after the configuration of the next router...
LabC - No OSPF at D yet
show ip ospf database
OSPF Router with ID (172.16.40.1) (Process ID 102)
Router Link States (Area 0)
Link ID ADV Router Age Seq# Checksum Link count
172.16.10.1 172.16.10.1 542 0x80000002 0x0067cd 1
172.16.20.1 172.16.20.1 90 0x80000004 0x00a551 3
172.16.40.1 172.16.40.1 37 0x80000004 0x00e47c 4
Net Link States (Area 0)
Link ID ADV Router Age Seq# Checksum
172.16.10.1 172.16.10.1 542 0x80000001 0x00953d
NOW we can see that the 20.1 link, which is the right-facing interface on LabB.. aka the router ID..
has THREE OSPF links.
Nothing changed on the left side of B. But on the right side, we now have an active OSPF router at the
other end of the link. This leads me to believe that the forum post was correct that 'serial links are counted twice',
but, more specifically, BOTH ENDS of the serial(PPP) link are counted... IF there is an OSPF router on each end.
This is backed up by the fact that LabC, OSPF id 40.1, has four OSPF links. The top-facing link to the 30
network DOES count.. even though it has no OSPF router on the other end. It counts because it's not a serial link.
The requirement of having an OSPF router on the other end for an interface to count here, only applies
to serial links. And pertains to BOTH ends of the link being counted.
In LabC's case, we have one serial at left, being counted twice. One ethernet at top, being counted once. And
one serial at right only being counted once because LabD is not active with OSPF yet.
If this is correct, then we should see Lab C's 40.1 count go to 5 after LabD is set for OSPF....
LabD - all 4 routers have OSPF
show ip ospf database
OSPF Router with ID (172.16.50.1) (Process ID 103)
Router Link States (Area 0)
Link ID ADV Router Age Seq# Checksum Link count
172.16.10.1 172.16.10.1 785 0x80000002 0x0067cd 1
172.16.20.1 172.16.20.1 333 0x80000004 0x00a551 3
172.16.40.1 172.16.40.1 111 0x80000005 0x00013b 5
172.16.50.1 172.16.50.1 53 0x80000003 0x001023 3
Net Link States (Area 0)
Link ID ADV Router Age Seq# Checksum
172.16.10.1 172.16.10.1 785 0x80000001 0x00953d
and back to LabC.....
show ip ospf database
OSPF Router with ID (172.16.40.1) (Process ID 102)
Router Link States (Area 0)
Link ID ADV Router Age Seq# Checksum Link count
172.16.10.1 172.16.10.1 1174 0x80000002 0x0067cd 1
172.16.20.1 172.16.20.1 722 0x80000004 0x00a551 3
172.16.40.1 172.16.40.1 500 0x80000005 0x00013b 5
172.16.50.1 172.16.50.1 441 0x80000003 0x001023 3
Net Link States (Area 0)
Link ID ADV Router Age Seq# Checksum
172.16.10.1 172.16.10.1 1174 0x80000001 0x00953d
Looks good! The link count for each router makes sense if you count the serial interfaces twice (one for each end).
the OSPF databases now match across all 4 routers.
NOTE that this is a database of routers, identified by
router ID. It is not a topology that lists routers AND routes, like in
the "equivalent" eigrp command show eigrp topology
Note that the .30 network is NOT represented here.
LabA#
show ip ospf database
OSPF Router with ID (172.16.10.1) (Process ID 100)
Router Link States (Area 0)
Link ID ADV Router Age Seq# Checksum Link count
172.16.10.1 172.16.10.1 1138 0x80000002 0x0067cd 1
172.16.20.1 172.16.20.1 686 0x80000004 0x00a551 3
172.16.40.1 172.16.40.1 463 0x80000005 0x00013b 5
172.16.50.1 172.16.50.1 404 0x80000003 0x001023 3
Net Link States (Area 0)
Link ID ADV Router Age Seq# Checksum
172.16.10.1 172.16.10.1 1138 0x80000001 0x00953d
LabB#
show ip ospf database
OSPF Router with ID (172.16.20.1) (Process ID 101)
Router Link States (Area 0)
Link ID ADV Router Age Seq# Checksum Link count
172.16.10.1 172.16.10.1 1151 0x80000002 0x0067cd 1
172.16.20.1 172.16.20.1 699 0x80000004 0x00a551 3
172.16.40.1 172.16.40.1 476 0x80000005 0x00013b 5
172.16.50.1 172.16.50.1 417 0x80000003 0x001023 3
Net Link States (Area 0)
Link ID ADV Router Age Seq# Checksum
172.16.10.1 172.16.10.1 1151 0x80000001 0x00953d
LabC#
show ip ospf database
OSPF Router with ID (172.16.40.1) (Process ID 102)
Router Link States (Area 0)
Link ID ADV Router Age Seq# Checksum Link count
172.16.10.1 172.16.10.1 1174 0x80000002 0x0067cd 1
172.16.20.1 172.16.20.1 722 0x80000004 0x00a551 3
172.16.40.1 172.16.40.1 500 0x80000005 0x00013b 5
172.16.50.1 172.16.50.1 441 0x80000003 0x001023 3
Net Link States (Area 0)
Link ID ADV Router Age Seq# Checksum
172.16.10.1 172.16.10.1 1174 0x80000001 0x00953d
LabD#
show ip ospf database
OSPF Router with ID (172.16.50.1) (Process ID 103)
Router Link States (Area 0)
Link ID ADV Router Age Seq# Checksum Link count
172.16.10.1 172.16.10.1 785 0x80000002 0x0067cd 1
172.16.20.1 172.16.20.1 333 0x80000004 0x00a551 3
172.16.40.1 172.16.40.1 111 0x80000005 0x00013b 5
172.16.50.1 172.16.50.1 53 0x80000003 0x001023 3
Net Link States (Area 0)
Link ID ADV Router Age Seq# Checksum
172.16.10.1 172.16.10.1 785 0x80000001 0x00953d
Below is our routing tables with OSPF data. We do see the .30 network here.
Everyone can reach it:
LabA via LabB's 10.2
LabB via LabC's 20.2
LabC via direct connection
LabD via LabC's 40.1
LabA#
show ip route
172.16.0.0/16 is variably subnetted, 6 subnets, 2 masks
C 172.16.10.0/24 is directly connected, FastEthernet0/0
L 172.16.10.1/32 is directly connected, FastEthernet0/0
O 172.16.20.0/24 [110/65] via 172.16.10.2, 00:28:03, FastEthernet0/0
O 172.16.30.0/24 [110/66] via 172.16.10.2, 00:21:35, FastEthernet0/0
O 172.16.40.0/24 [110/129] via 172.16.10.2, 00:21:25, FastEthernet0/0
O 172.16.50.0/24 [110/130] via 172.16.10.2, 00:17:40, FastEthernet0/0
LabB#
show ip route
172.16.0.0/16 is variably subnetted, 7 subnets, 2 masks
C 172.16.10.0/24 is directly connected, FastEthernet0/0
L 172.16.10.2/32 is directly connected, FastEthernet0/0
C 172.16.20.0/24 is directly connected, Serial0/0/0
L 172.16.20.1/32 is directly connected, Serial0/0/0
O 172.16.30.0/24 [110/65] via 172.16.20.2, 00:27:04, Serial0/0/0
O 172.16.40.0/24 [110/128] via 172.16.20.2, 00:26:54, Serial0/0/0
O 172.16.50.0/24 [110/129] via 172.16.20.2, 00:23:09, Serial0/0/0
LabC#
show ip route
172.16.0.0/16 is variably subnetted, 8 subnets, 2 masks
O 172.16.10.0/24 [110/65] via 172.16.20.1, 00:27:52, Serial0/0/0
C 172.16.20.0/24 is directly connected, Serial0/0/0
L 172.16.20.2/32 is directly connected, Serial0/0/0
C 172.16.30.0/24 is directly connected, FastEthernet0/0
L 172.16.30.1/32 is directly connected, FastEthernet0/0
C 172.16.40.0/24 is directly connected, Serial0/0/1
L 172.16.40.1/32 is directly connected, Serial0/0/1
O 172.16.50.0/24 [110/65] via 172.16.40.2, 00:23:36, Serial0/0/1
LabD#
show ip route
172.16.0.0/16 is variably subnetted, 7 subnets, 2 masks
O 172.16.10.0/24 [110/129] via 172.16.40.1, 00:25:20, Serial0/0/0
O 172.16.20.0/24 [110/128] via 172.16.40.1, 00:25:20, Serial0/0/0
O 172.16.30.0/24 [110/65] via 172.16.40.1, 00:25:20, Serial0/0/0
C 172.16.40.0/24 is directly connected, Serial0/0/0
L 172.16.40.2/32 is directly connected, Serial0/0/0
C 172.16.50.0/24 is directly connected, FastEthernet0/0
L 172.16.50.1/32 is directly connected, FastEthernet0/0
moving on.......
9.5 - OSPF DR and BDR Elections
EachRouter(config)#
hostname X (A, B, or C)
EachRouter(config)#
line con 0
EachRouter(config-line)#
exec-timeout 0 0
A(config)#
int f0/0
A(config-if)#
ip addr 10.1.1.1 255.255.255.0
A(config-if)#
no shut
A(config)#
router ospf 12345
A(config-router)#
net 10.1.1.0 0.0.0.255 area 0
00:23:30: %OSPF-5-ADJCHG: Process 12345, Nbr 10.1.1.3 on FastEthernet0/0 from LOADING to FULL, Loading Done
00:23:30: %OSPF-5-ADJCHG: Process 12345, Nbr 10.1.1.2 on FastEthernet0/0 from LOADING to FULL, Loading Done
A#
show ip ospf int
note this output was generated AFTER all 3 routers set for OSPF
FastEthernet0/0 is up, line protocol is up
Internet address is 10.1.1.1/24, Area 0
Process ID 12345, Router ID 10.1.1.1, Network Type BROADCAST, Cost: 1
Transmit Delay is 1 sec, State DROTHER, Priority 1
Designated Router (ID) 10.1.1.3, Interface address 10.1.1.3
Backup Designated Router (ID) 10.1.1.2, Interface address 10.1.1.2
Timer intervals configured, Hello 10, Dead 40, Wait 40, Retransmit 5
Hello due in 00:00:04
Index 1/1, flood queue length 0
Next 0x0(0)/0x0(0)
Last flood scan length is 1, maximum is 1
Last flood scan time is 0 msec, maximum is 0 msec
Neighbor Count is 2, Adjacent neighbor count is 2
Adjacent with neighbor 10.1.1.3 (Designated Router)
Adjacent with neighbor 10.1.1.2 (Backup Designated Router)
Suppress hello for 0 neighbor(s)
A(config-if)#shut
A(config-if)#
%LINK-5-CHANGED: Interface FastEthernet0/0, changed state to administratively down
%LINEPROTO-5-UPDOWN: Line protocol on Interface FastEthernet0/0, changed state to down
00:40:28: %OSPF-5-ADJCHG: Process 12345, Nbr 10.1.1.2 on FastEthernet0/0 from FULL to DOWN, Neighbor Down: Interface down or detached
00:40:28: OSPF: Build router LSA for area 0, router ID 10.1.1.1, seq 0xffffffff80000003
00:40:28: %OSPF-5-ADJCHG: Process 12345, Nbr 10.1.1.3 on FastEthernet0/0 from FULL to DOWN, Neighbor Down: Interface down or detached
00:40:28: OSPF: Build router LSA for area 0, router ID 10.1.1.1, seq 0xffffffff80000004
00:40:28: OSPF: Build router LSA for area 0, router ID 10.1.1.1, seq 0xffffffff80000004
A(config-if)#no shut
A(config-if)#
%LINK-5-CHANGED: Interface FastEthernet0/0, changed state to up
%LINEPROTO-5-UPDOWN: Line protocol on Interface FastEthernet0/0, changed state to up
00:40:48: OSPF: Build router LSA for area 0, router ID 10.1.1.1, seq 0xffffffff80000004
00:41:27: OSPF: Backup seen Event before WAIT timer on FastEthernet0/0
00:41:27: OSPF: DR/BDR election on FastEthernet0/0
00:41:27: OSPF: Elect BDR 10.1.1.2
00:41:27: OSPF: Elect DR 10.1.1.3
00:41:27: DR: 10.1.1.3 (Id) BDR: 10.1.1.2 (Id)
00:41:27: OSPF: Send DBD to 10.1.1.3 on FastEthernet0/0 seq 0x5accb8e2 opt 0x00 flag 0x7 len 32
B(config)#
int f0/0
B(config-if)#
ip addr 10.1.1.2 255.255.255.0
B(config-if)#
no shut
B(config)#
router ospf 12345
B(config-router)#
net 10.1.1.0 0.0.0.255 area 0
00:23:29: %OSPF-5-ADJCHG: Process 12345, Nbr 10.1.1.3 on FastEthernet0/0 from LOADING to FULL, Loading Done
00:23:29: %OSPF-5-ADJCHG: Process 12345, Nbr 10.1.1.1 on FastEthernet0/0 from LOADING to FULL, Loading Done
B#
show ip ospf int
note this output was generated AFTER all 3 routers set for OSPF
FastEthernet0/0 is up, line protocol is up
Internet address is 10.1.1.2/24, Area 0
Process ID 12345, Router ID 10.1.1.2, Network Type BROADCAST, Cost: 1
Transmit Delay is 1 sec, State BDR, Priority 1
Designated Router (ID) 10.1.1.3, Interface address 10.1.1.3
Backup Designated Router (ID) 10.1.1.2, Interface address 10.1.1.2
Timer intervals configured, Hello 10, Dead 40, Wait 40, Retransmit 5
Hello due in 00:00:05
Index 1/1, flood queue length 0
Next 0x0(0)/0x0(0)
Last flood scan length is 1, maximum is 1
Last flood scan time is 0 msec, maximum is 0 msec
Neighbor Count is 2, Adjacent neighbor count is 2
Adjacent with neighbor 10.1.1.1
Adjacent with neighbor 10.1.1.3 (Designated Router)
Suppress hello for 0 neighbor(s)
B#debug ip ospf adj
OSPF adjacency events debugging is on
B#
00:39:21: OSPF: DR/BDR election on FastEthernet0/0
00:39:21: OSPF: Elect BDR 10.1.1.2
00:39:21: OSPF: Elect DR 10.1.1.3
00:39:21: DR: 10.1.1.3 (Id) BDR: 10.1.1.2 (Id)
00:41:01: %OSPF-5-ADJCHG: Process 12345, Nbr 10.1.1.1 on FastEthernet0/0 from FULL to DOWN, Neighbor Down: Dead timer expired
00:41:01: %OSPF-5-ADJCHG: Process 12345, Nbr 10.1.1.1 on FastEthernet0/0 from FULL to DOWN, Neighbor Down: Interface down or detached
00:41:01: OSPF: Build router LSA for area 0, router ID 10.1.1.2, seq 0xffffffff80000003
00:41:01: OSPF: DR/BDR election on FastEthernet0/0
00:41:01: OSPF: Elect BDR 10.1.1.2
00:41:01: OSPF: Elect DR 10.1.1.3
C(config)#
int f0/0
C(config-if)#
ip addr 10.1.1.3 255.255.255.0
C(config-if)#
no shut
C(config)#
router ospf 12345
C(config-router)#
net 10.1.1.0 0.0.0.255 area 0
00:23:27: %OSPF-5-ADJCHG: Process 12345, Nbr 10.1.1.1 on FastEthernet0/0 from LOADING to FULL, Loading Done
00:23:27: %OSPF-5-ADJCHG: Process 12345, Nbr 10.1.1.2 on FastEthernet0/0 from LOADING to FULL, Loading Done
C#
show ip ospf int
note this output was generated AFTER all 3 routers set for OSPF
FastEthernet0/0 is up, line protocol is up
Internet address is 10.1.1.3/24, Area 0
Process ID 12345, Router ID 10.1.1.3, Network Type BROADCAST, Cost: 1
Transmit Delay is 1 sec, State DR, Priority 1
Designated Router (ID) 10.1.1.3, Interface address 10.1.1.3
Backup Designated Router (ID) 10.1.1.2, Interface address 10.1.1.2
Timer intervals configured, Hello 10, Dead 40, Wait 40, Retransmit 5
Hello due in 00:00:00
Index 1/1, flood queue length 0
Next 0x0(0)/0x0(0)
Last flood scan length is 1, maximum is 1
Last flood scan time is 0 msec, maximum is 0 msec
Neighbor Count is 2, Adjacent neighbor count is 2
Adjacent with neighbor 10.1.1.1
Adjacent with neighbor 10.1.1.2 (Backup Designated Router)
Suppress hello for 0 neighbor(s)
C#debug ip ospf adj
OSPF adjacency events debugging is on
C#
00:39:19: OSPF: DR/BDR election on FastEthernet0/0
00:39:19: OSPF: Elect BDR 10.1.1.2
00:39:19: OSPF: Elect DR 10.1.1.3
00:39:19: DR: 10.1.1.3 (Id) BDR: 10.1.1.2 (Id)
00:40:59: %OSPF-5-ADJCHG: Process 12345, Nbr 10.1.1.1 on FastEthernet0/0 from FULL to DOWN, Neighbor Down: Dead timer expired
00:40:59: %OSPF-5-ADJCHG: Process 12345, Nbr 10.1.1.1 on FastEthernet0/0 from FULL to DOWN, Neighbor Down: Interface down or detached
00:40:59: OSPF: Build router LSA for area 0, router ID 10.1.1.3, seq 0xffffffff80000003
00:40:59: OSPF: Build net LSA for area 0, router ID 10.1.1.3, seq 0xffffffff80000003
00:40:59: OSPF: DR/BDR election on FastEthernet0/0
00:40:59: OSPF: Elect BDR 10.1.1.2
00:40:59: OSPF: Elect DR 10.1.1.3
DR and BDR automtically set based on higest IP address
Note our network type is BROADCAST because we're using ethernet interfaces...
it would be point-to-point if using a serial connection
we want to manually overide the priority of the router. ZERO priority means it wont participate in the election process
MAX priority of 255 means no other router can beat it for DR
We'll set the priority for router A to 3.
It will beome the DR only after we shut/no shut the interface router
AND
manually power on/off the other two routers
A(config)#
int f0/0
A(config-int)#
ip ospf priority 3
A(config-int)#
shut
A(config-int)#
no shut
A#
debug ip ospf adj
B#
debug ip ospf adj
00:05:50: OSPF: DR/BDR election on FastEthernet0/0
00:05:50: OSPF: Elect BDR 10.1.1.2
00:05:50: OSPF: Elect DR 10.1.1.1
00:05:50: OSPF: Elect BDR 10.1.1.2
00:05:50: OSPF: Elect DR 10.1.1.1
00:05:50: DR: 10.1.1.1 (Id) BDR: 10.1.1.2 (Id)
00:05:50: OSPF: Send DBD to 10.1.1.1 on FastEthernet0/0 seq 0x10164ebb opt 0x00 flag 0x7 len 32
00:05:50: OSPF: Build router LSA for area 0, router ID 10.1.1.2, seq 0xffffffff80000002
00:05:52: OSPF: Rcv DBD from 10.1.1.1 on FastEthernet0/0 seq 0x20368093 opt 0x00 flag 0x7 len 32 mtu 1500 state EXSTART
00:05:52: OSPF: First DBD and we are not SLAVE
00:05:55: OSPF: Send DBD to 10.1.1.1 on FastEthernet0/0 seq 0x10164ebb opt 0x00 flag 0x7 len 32
00:05:55: OSPF: Rcv DBD from 10.1.1.1 on FastEthernet0/0 seq 0x10164ebb opt 0x00 flag 0x2 len 112 mtu 1500 state EXSTART
00:05:55: OSPF: NBR Negotiation Done. We are the MASTER
00:05:55: OSPF: Send DBD to 10.1.1.1 on FastEthernet0/0 seq 0x10164ebc opt 0x00 flag 0x3 len 52
00:05:55: OSPF: Rcv DBD from 10.1.1.1 on FastEthernet0/0 seq 0x10164ebc opt 0x00 flag 0x0 len 32 mtu 1500 state EXCHANGE
00:05:55: OSPF: Send DBD to 10.1.1.1 on FastEthernet0/0 seq 0x10164ebd opt 0x00 flag 0x1 len 32
00:05:55: OSPF: Rcv DBD from 10.1.1.1 on FastEthernet0/0 seq 0x10164ebd opt 0x00 flag 0x0 len 32 mtu 1500 state EXCHANGE
00:05:55: Exchange Done with 10.1.1.1 on FastEthernet0/0
00:05:55: OSPF: Database request to 10.1.1.1
00:05:55: OSPF: sent LS REQ packet to 10.1.1.1, length 36
00:05:55: OSPF: Rcv DBD from 10.1.1.1 on FastEthernet0/0 seq 0x10164ebd opt 0x00 flag 0x0 len 32 mtu 1500 state LOADING
00:05:55: Synchronized with with 10.1.1.1 on FastEthernet0/0, state FULL
00:05:55: %OSPF-5-ADJCHG: Process 12345, Nbr 10.1.1.1 on FastEthernet0/0 from LOADING to FULL, Loading Done
00:05:55: OSPF: Build router LSA for area 0, router ID 10.1.1.2, seq 0xffffffff80000002
C#
debug ip ospf adj
00:06:13: OSPF: DR/BDR election on FastEthernet0/0
00:06:13: OSPF: Elect BDR 10.1.1.2
00:06:13: OSPF: Elect DR 10.1.1.1
00:06:13: DR: 10.1.1.1 (Id) BDR: 10.1.1.2 (Id)
00:06:13: OSPF: Send DBD to 10.1.1.1 on FastEthernet0/0 seq 0x1cc5536d opt 0x00 flag 0x7 len 32
00:06:13: OSPF: Send DBD to 10.1.1.2 on FastEthernet0/0 seq 0x3d51ca66 opt 0x00 flag 0x7 len 32
00:06:13: OSPF: Build router LSA for area 0, router ID 10.1.1.3, seq 0xffffffff80000002
00:06:17: OSPF: Rcv DBD from 10.1.1.1 on FastEthernet0/0 seq 0x6b532eec opt 0x00 flag 0x7 len 32 mtu 1500 state EXSTART
00:06:17: OSPF: First DBD and we are not SLAVE
00:06:17: OSPF: Rcv DBD from 10.1.1.2 on FastEthernet0/0 seq 0x783110f4 opt 0x00 flag 0x7 len 32 mtu 1500 state EXSTART
00:06:17: OSPF: First DBD and we are not SLAVE
00:06:18: OSPF: Send DBD to 10.1.1.2 on FastEthernet0/0 seq 0x3d51ca66 opt 0x00 flag 0x7 len 32
00:06:18: OSPF: Send DBD to 10.1.1.1 on FastEthernet0/0 seq 0x1cc5536d opt 0x00 flag 0x7 len 32
00:06:18: OSPF: Rcv DBD from 10.1.1.2 on FastEthernet0/0 seq 0x3d51ca66 opt 0x00 flag 0x2 len 132 mtu 1500 state EXSTART
00:06:18: OSPF: NBR Negotiation Done. We are the MASTER
00:06:18: OSPF: Send DBD to 10.1.1.2 on FastEthernet0/0 seq 0x3d51ca67 opt 0x00 flag 0x3 len 52
00:06:18: OSPF: Rcv DBD from 10.1.1.1 on FastEthernet0/0 seq 0x1cc5536d opt 0x00 flag 0x2 len 132 mtu 1500 state EXSTART
00:06:18: OSPF: NBR Negotiation Done. We are the MASTER
00:06:18: OSPF: Send DBD to 10.1.1.1 on FastEthernet0/0 seq 0x1cc5536e opt 0x00 flag 0x3 len 52
00:06:18: OSPF: Rcv DBD from 10.1.1.2 on FastEthernet0/0 seq 0x3d51ca67 opt 0x00 flag 0x0 len 32 mtu 1500 state EXCHANGE
00:06:18: OSPF: Send DBD to 10.1.1.2 on FastEthernet0/0 seq 0x3d51ca68 opt 0x00 flag 0x1 len 32
00:06:18: OSPF: Rcv DBD from 10.1.1.1 on FastEthernet0/0 seq 0x1cc5536e opt 0x00 flag 0x0 len 32 mtu 1500 state EXCHANGE
00:06:18: OSPF: Send DBD to 10.1.1.1 on FastEthernet0/0 seq 0x1cc5536f opt 0x00 flag 0x1 len 32
00:06:18: OSPF: Rcv DBD from 10.1.1.2 on FastEthernet0/0 seq 0x3d51ca68 opt 0x00 flag 0x0 len 32 mtu 1500 state EXCHANGE
00:06:18: Exchange Done with 10.1.1.2 on FastEthernet0/0
00:06:18: OSPF: Database request to 10.1.1.2
00:06:18: OSPF: sent LS REQ packet to 10.1.1.2, length 48
00:06:18: OSPF: Rcv DBD from 10.1.1.1 on FastEthernet0/0 seq 0x1cc5536f opt 0x00 flag 0x0 len 32 mtu 1500 state EXCHANGE
verify on all three routers
A#
show ip ospf interface f0/0
FastEthernet0/0 is up, line protocol is up
Internet address is 10.1.1.1/24, Area 0
Process ID 12345, Router ID 10.1.1.1, Network Type BROADCAST, Cost: 1
Transmit Delay is 1 sec, State DR, Priority 3
Designated Router (ID) 10.1.1.1, Interface address 10.1.1.1
Backup Designated Router (ID) 10.1.1.2, Interface address 10.1.1.2
Timer intervals configured, Hello 10, Dead 40, Wait 40, Retransmit 5
Hello due in 00:00:09
Index 1/1, flood queue length 0
Next 0x0(0)/0x0(0)
Last flood scan length is 1, maximum is 1
Last flood scan time is 0 msec, maximum is 0 msec
Neighbor Count is 2, Adjacent neighbor count is 2
Adjacent with neighbor 10.1.1.2 (Backup Designated Router)
Adjacent with neighbor 10.1.1.3
Suppress hello for 0 neighbor(s)
A#
show ip ospf neighbor
Neighbor ID Pri State Dead Time Address Interface
10.1.1.2 1 FULL/BDR 00:00:37 10.1.1.2 FastEthernet0/0
10.1.1.3 1 FULL/DROTHER 00:00:30 10.1.1.3 FastEthernet0/0
B#
show ip ospf interface f0/0
FastEthernet0/0 is up, line protocol is up
Internet address is 10.1.1.2/24, Area 0
Process ID 12345, Router ID 10.1.1.2, Network Type BROADCAST, Cost: 1
Transmit Delay is 1 sec, State BDR, Priority 1
Designated Router (ID) 10.1.1.1, Interface address 10.1.1.1
Backup Designated Router (ID) 10.1.1.2, Interface address 10.1.1.2
Timer intervals configured, Hello 10, Dead 40, Wait 40, Retransmit 5
Hello due in 00:00:08
Index 1/1, flood queue length 0
Next 0x0(0)/0x0(0)
Last flood scan length is 1, maximum is 1
Last flood scan time is 0 msec, maximum is 0 msec
Neighbor Count is 2, Adjacent neighbor count is 2
Adjacent with neighbor 10.1.1.1 (Designated Router)
Adjacent with neighbor 10.1.1.3
Suppress hello for 0 neighbor(s)
B#
show ip ospf neighbor
Neighbor ID Pri State Dead Time Address Interface
10.1.1.1 3 FULL/DR 00:00:35 10.1.1.1 FastEthernet0/0
10.1.1.3 1 FULL/DROTHER 00:00:31 10.1.1.3 FastEthernet0/0
C#
show ip ospf interface f0/0
FastEthernet0/0 is up, line protocol is up
Internet address is 10.1.1.3/24, Area 0
Process ID 12345, Router ID 10.1.1.3, Network Type BROADCAST, Cost: 1
Transmit Delay is 1 sec, State DROTHER, Priority 1
Designated Router (ID) 10.1.1.1, Interface address 10.1.1.1
Backup Designated Router (ID) 10.1.1.2, Interface address 10.1.1.2
Timer intervals configured, Hello 10, Dead 40, Wait 40, Retransmit 5
Hello due in 00:00:06
Index 1/1, flood queue length 0
Next 0x0(0)/0x0(0)
Last flood scan length is 1, maximum is 1
Last flood scan time is 0 msec, maximum is 0 msec
Neighbor Count is 2, Adjacent neighbor count is 2
Adjacent with neighbor 10.1.1.1 (Designated Router)
Adjacent with neighbor 10.1.1.2 (Backup Designated Router)
Suppress hello for 0 neighbor(s)
C#
show ip ospf neighbor/span>
Neighbor ID Pri State Dead Time Address Interface
10.1.1.1 3 FULL/DR 00:00:35 10.1.1.1 FastEthernet0/0
10.1.1.2 1 FULL/BDR 00:00:37 10.1.1.2 FastEthernet0/0
Router1 is the DR with priority 3
still need more work to understand the output of the defbu ospf adj
Chapter 9 Review Questions
1. There are three possible routes for a router to reach a destination network:
OSPF with a metric of 782
RIPv2 with a metric of 4
EIGRP with a composite metric of 20514560
Which route will be installed in the routing table?
EIGRP because it has the lowest Administrative Distance, and AD is always used before metric
ADs are:
ExternalEIGRP 170
RIP 120
OSPF 110
IGRP 100
EIGRP 90
Static 1
Connected 0
2. Which EIGRP information is held in RAM and maintained through the use of Hello and update packets?
Neighbor table
and
toplogy table
3. Describe the process identifier that is used to run OSPF on a router
The OSPF process id is only locally significant. A random number can be selected. But it's required in order to identify
a unique OSPF database instance. You can use the same, or a different number on each router, doesnt matter.
Any number can be used from 1 to 65,535. Process ID is supplied as an argument to the command router ospf
NOT to be confused with the area number which can be any number up to 4 billion. The area id identifies a logical grouping of routers.
area id is supplied as argument to the OSPF network id and mask command
Ex:
R1(config)#
router ospf 12345
R1(config-router)#
net 10.1.1.0 0.0.0.255 area 0
4. Where are EIGRP successor routes stored?
EIGRP succesor routers are stored in the routing table. The "succesor" is the successful or primary route.
The successor route is ALSO listed in the topology table,
The feasible successor is a BACKUP route and will ONLY be listed in the topology table, unless the successor route fails,
in which case the feasible successor would become the successor
Note that my EIGRP setup doesnt seem to folow this.
CTRL-F jump to "remotely connected via remote ingress ip address"
the book states that EIGRP is automatically load-balancing our two links from R1 to corp.. is this why there is no feasible successor here?
I did some research and found that in our case, we are not using a Feasible Successor. You CAN have two Successors with equal metric, in which case EIGRP will
automatically load-balance.
But I wanted to find out what a Feasible Successor actually looks like in the EIGRP topology table..
Kevin Wallace EIGRP article
Conclusion:
EIGRP topology table wouldnt specifically say "Feasible Successor", but you would know by two routes appearing, one with a lower metric.
In my topology we have two equal-metric links and they are both considered "Successors". EIGRP uses them equally (load-balanced)
Corp#
show ip eigrp toplogy
[cut]
P 172.16.10.0/24, 1 successors, FD is 28160
via 10.1.5.2 (28160/25600), FastEthernet0/0
P 192.168.10.0/24, 2 successors, FD is 2172416
via 10.1.3.2 (2172416/28160), Serial0/0/1
via 10.1.2.2 (2172416/28160), Serial0/0/0
P 192.168.20.0/24, 2 successors, FD is 2172416
via 10.1.3.2 (2172416/28160), Serial0/0/1
via 10.1.2.2 (2172416/28160), Serial0/0/0
P 192.168.30.0/24, 1 successors, FD is 2172416
via 10.1.4.2 (2172416/28160), Serial0/1/0
P 192.168.40.0/24, 1 successors, FD is 2172416
via 10.1.4.2 (2172416/28160), Serial0/1/0
5. Which command will display all the EIGRP feasible successor routes to a known router.
show ip eigrp topology
6. Find the configuration error. You type the following into your router, but dont see any routes in the routing table?
Router(config)#
router ospf 1
Router(config-router)#
network 10.0.0.0 255.0.0.0
wrong wildcard mask
instead, could have used
0.255.255.255
or
0.0.0.255
the point is we need to specify the first octet as "allowed" into our OSPF config with a 0 mask.
The remaining bits are 'dont care' bits aka 'wildcard' aka 255
7. Which three protocols support VLSM, summarization, and discontigous networking?
RIPv2
EIGRP
OSPF
all 3 build and mainting routing tables, provide classless routing which allows VLSM, summarization, and discontigous networks
RIPv1 and IGRP build/maintain routing tables, but dont offer classless routing
8. Which are true regarding OSPF areas?
the 'backbone' is area 0
if using other areas, they all must directly connect to area 0
9. Which two network types have a designated router and a backup designated router?
Broadcast
NBMA- Non broadcast multi access. Ex: Frame Relay
network types that DO NOT use DR/BDR:
point to point
broadcast multipoint
10. You need to configure a router with a distance-vector protocol that allows classless routing. Which to use?
EIGRP is considered 'advanced distance vector' (ripv2 wasnt an option)
11. You need the IP address of the devices with which the router has established an adjacency.
Also, the retransmit interval and the queue counts for the adjacent routers need to be checked. What command will display the required information?
show ip eigrp neighbors
WRONG: show ip eigrp adjacency - there is no such command.. the word 'adjacency' is only used with debug ip OSPF adjacency
here are the possible commands for show ip eigrp and debug ip eigrp
show ip eigrp ?
interfaces IP-EIGRP interfaces
neighbors IP-EIGRP neighbors
topology IP-EIGRP Topology Table
traffic IP-EIGRP Traffic Statistics
debug ip eigrp ?
summary IP-EIGRP summary route processing
12. You cant establish an adjacency relationship on a common ethernet link between two routers. Based on the output below, what is the cause of the problem?
RouterA#
Ethernet0/0 is up, line protocol is up
Internet Address 172.16.1.2/16, Area 0
Process ID 2, Router ID 172.126.1.2, Network Type BROADCAST, Cost: 10
Transmit Delay is 1 sec, State DR, Priority 1
Designated Router (ID) 172.16.1.2, interface address 172.16.1.1.
No backup designated router on this network
Timer intervals configured, Hello 5, Dead 20, Wait 20, Retransmit 5
Router B#
Internet Address 172.16.1.1/16, Area 0
Process ID 2, Router ID 172.126.1.1, Network Type BROADCAST, Cost: 10
Transmit Delay is 1 sec, State DR, Priority 1
Designated Router (ID) 172.16.1.1, interface address 172.16.1.2.
No backup designated router on this network
Timer intervals configured, Hello 10, Dead 40, Wait 40, Retransmit 5
mismatched timer intervals
OSPF default Hello is 10 and Dead is 40... RouterA was modified
13. Which is true regarding EIGRP successor routes?
Used in the routing table
also appears in the topolgy table
may (or may not) have a backup feasabile successor
14. Which type of OSPF network will elect a backup designated router?
broadcast multi-access
non-broadcast multiaccess
types of network that will NOT elect a BDR:
point to point and brodacast multipoint (hub/spoke topology)
15. Which two commands will place network 10.2.3.0/24 into area 0?
Router(config)#
router ospf 10
Router(config-router)#
network 10.2.3.0 0.0.0.255 area 0
16. With which network type will OSPF establish router adjacencies but not perform the DR/BDR election process?
Point to point
no election process occurs, there is never a DR on point to point
17. What are three reasons for creating OSPF in a heirarchical design?
decrease routing overhead
speed up convergence
confine stability to single areas of the network
18. What is the administrative distance of OSPF?
110
19.
no auto summary
the network is considered discontigous because we have two classful network subnetted (on the left and right),
seperated by a different classful address.
if auto summarization is taking place, the routers cant determine which side is which because both sides would be summarized as
Class B, 172.16.0.0, which isnt specific enough to distinguish between the sides.
20. IF routers in a single area are configured with the same priority value, what value does a router use for the OSPF router ID in the absence of a loopback interface?
The highest IP of any PHSYICAL interface.
Trick question. Highest IP of any LOGICAL interface is an option. And is correct IF you had logical interfaces, but the question
states that any "logical interfaces are absent".
At OSPF startup, the highest IP of *any* active interface on the router becomes the OSPF router ID. If you have loopback (logical) interfaces configured,
one of them (the largest IP) will *override* the phsyical interfaces and the loopback IP becomes the RID.
Reference for which loopback (if multiple) wins:
packetpushers.net
------------------------------------------------------------------------------
END CHAPTER 9
41 hours 2-14 thru 2-28-22
original total 184 hours
14 hours review 12-26 thru 12-28-22
review total hours 46
book page 502/822
184 + 46 = 230 hours * 60 = (13,800 min) / 500 pages =
avg 28 min/page (includes reading and exercises/labs + online research)
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1. verify connection to the server
R1# ping 193.1.1.1
2. show contents of flash memory
R1# show flash
3. show the IOS currently running
R1# show version
4. backup IOS from router to server
R1# copy flash tftp
R1# ping 193.1.1.1
Type escape sequence to abort.
Sending 5, 100-byte ICMP Echos to 193.1.1.2, timeout is 2 seconds:
.!!!!
Success rate is 80 percent (4/5), round-trip min/avg/max = 0/1/5 ms
2. show contents of flash memory
R1# show flash
System flash directory:
File Length Name/status
3 486899872isr4300-universalk9.16.06.04.SPA.bin
2 28282 sigdef-category.xml
1 227537 sigdef-default.xml
[487155691 bytes used, 2761893909 available, 3249049600 total]
3.17338e+06K bytes of processor board System flash (Read/Write)
show flash gives ALL of the files in flash memory
show version gives the current running file
show version gives the current running file
3. show the IOS currently running
R1# show version
Cisco IOS XE Software, Version 03.16.05.S - Extended Support Release
[cut]
ROM: IOS-XE ROMMON
Router uptime is 9 minutes, 39 seconds
Uptime for this control processor is 9 minutes, 39 seconds
System returned to ROM by power-on
System image file is "bootflash:/isr4300-universalk9.03.16.05.S.155-3.S5-ext.SPA.bin"
Last reload reason: PowerOn
[cut]
note that the file that is currently running is NOT located in the flash storage!!!
4. backup IOS from router to server
R1# copy flash tftp
Source filename []?isr4300-universalk9.16.06.04.SPA.bin
Address or name of remote host []? 193.1.1.4
Destination filename [isr4300-universalk9.16.06.04.SPA.bin]? ENTER
Writing isr4300-universalk9.16.06.04.SPA.bin...!!!!!!!!!!!!!!!
[OK - 486899872 bytes]
486899872 bytes copied in 12.526 secs (125224 bytes/sec)
1. verify connection to the server
R1# ping 193.1.1.4
2. copy from tftp sever to flash
R1# copy tftp flash TFTP comes first in the command since we are pulling from TFTP server. In this command, remot host address is required before file name
R1# ping 193.1.1.4
Type escape sequence to abort.
Sending 5, 100-byte ICMP Echos to 193.1.1.2, timeout is 2 seconds:
!!!!!
Success rate is 100 percent (5/5), round-trip min/avg/max = 0/0/1 ms
2. copy from tftp sever to flash
R1# copy tftp flash TFTP comes first in the command since we are pulling from TFTP server. In this command, remot host address is required before file name
Address or name of remote host []? 193.1.1.4
Source filename []?isr4300-universalk9.16.06.04.SPA.bin
Destination filename [isr4300-universalk9.16.06.04.SPA.bin]? ENTER
%Warning:There is a file already existing with this name
Do you want to over write? [confirm]
Accessing tftp://193.1.1.4/isr4300-universalk9.16.06.04.SPA-12-23-22...
Loading isr4300-universalk9.16.06.04.SPA-12-23-22.bin from 193.1.1.4: !!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!
[OK - 486899872 bytes]
486899872 bytes copied in 12.785 secs (122688 bytes/sec)
Chapter 7 Hands-on Lab 7.3 Backing up the router configuration
1. verify connection to the server
R1#
ping 193.1.1.2
Type escape sequence to abort.
Sending 5, 100-byte ICMP Echos to 193.1.1.4, timeout is 2 seconds:
!!!!!
Success rate is 100 percent (5/5), round-trip min/avg/max = 0/0/1 ms
2. copy running-confing to server
R1#
copy run tftp
Address or name of remote host []? 193.1.1.4
Destination filename [R1-confg]?ENTER "R1-confg" is the default name
Writing running-config...!!
[OK - 668 bytes]
668 bytes copied in 0.004 secs (167000 bytes/sec)
Chapter 7 Hands-on Lab 7.4 Using the Cisco Discovery Protocol (CDP)
R1#
show cdp
Global CDP information:
Sending CDP packets every 60 seconds
Sending a holdtime value of 180 seconds
Sending CDPv2 advertisements is enabled
R1#
show cdp interface
Vlan1 is administratively down, line protocol is down
Sending CDP packets every 60 seconds
Holdtime is 180 seconds
GigabitEthernet0/0/0 is up, line protocol is up
Sending CDP packets every 60 seconds
Holdtime is 180 seconds
GigabitEthernet0/0/1 is administratively down, line protocol is down
Sending CDP packets every 60 seconds
Holdtime is 180 seconds
GigabitEthernet0/0/2 is administratively down, line protocol is down
Sending CDP packets every 60 seconds
Holdtime is 180 seconds
R1#
show cdp entry *
Device ID: SW1
Entry address(es):
Platform: cisco 2960, Capabilities: Switch
Interface: GigabitEthernet0/0/0, Port ID (outgoing port): FastEthernet0/1
NOTE g0/0/0 is the outgoing port on this router, F0/1 is the port on the switch at other end
Holdtime: 157
Version :
Cisco IOS Software, C2960 Software (C2960-LANBASEK9-M), Version 15.0(2)SE4, RELEASE SOFTWARE (fc1)
Technical Support: http://www.cisco.com/techsupport
Copyright (c) 1986-2013 by Cisco Systems, Inc.
Compiled Wed 26-Jun-13 02:49 by mnguyen
advertisement version: 2
Duplex: full
R1#
show cdp entry neighbors
[no output]
R1#
show cdp neighbors detail
Device ID: SW1
Entry address(es):
Platform: cisco 2960, Capabilities: Switch
Interface: GigabitEthernet0/0/0, Port ID (outgoing port): FastEthernet0/1
Holdtime: 178
Version :
Cisco IOS Software, C2960 Software (C2960-LANBASEK9-M), Version 15.0(2)SE4, RELEASE SOFTWARE (fc1)
Technical Support: http://www.cisco.com/techsupport
Copyright (c) 1986-2013 by Cisco Systems, Inc.
Compiled Wed 26-Jun-13 02:49 by mnguyen
advertisement version: 2
Duplex: full
Chapter 7 Hands-on Lab 7.5 Using Telnet
enable telnet on R2 and set password
R2(config)#
line vty 0 15
R2(config-line)#
password telnet
R2(config-line)#
login
enable telnet on R3 and set password
R3(config)#
line vty 0 15
R3(config-line)#
password telnet
R3(config-line)#
login
note that the result of this command on each router, by default,
is to present all 15 lines in TWO SEPERATE chunks: 0-4 and 5-15
R3#
show run
[cut]
!
!
!
line con 0
!
line aux 0
!
line vty 0 4
password telnet
login
line vty 5 15
password telnet
login
!
!
!
end
--------------------------------------------------------------------------------
connect to R2 from R1
R1#
telnet 193.1.1.2
Trying 193.1.1..2 ...Open
User Access Verification
Password: telnet
prompt changes to R2 to indicate we are remoted in
R2>
exit the session
ctrl + shift + 6, x
prompt changes back to R1
R1#
--------------------------------------------------------------------------------
connect to R3 from R1
R1#
193.1.1.3 note that the word 'telnet' is not required bc we are still in telnet mode
Trying 193.1.1..3 ...Open
User Access Verification
Password: telnet
prompt changes to R3 to indicate we are remoted in
R3>
exit the session
ctrl + shift + 6, x
prompt changes back to R1
R1#
--------------------------------------------------------------------------------
We have exited the sessions, but they are still open
R1#
show sessions
Conn Host Address Byte Idle Conn Name
1 193.1.1.2 193.1.1.2 0 0 193.1.1.2
* 2 193.1.1.3 193.1.1.3 0 0 193.1.1.3
two telnet sessions- notice that the 'conn number' doesnt correspond to ip address in any way.
R1#
show users
Line User Host(s) Idle Location
* 0 con 0 193.1.1.2 00:00:03
193.1.1.3 00:00:43
this is saying one user is on this router, with two outbound connections (but it isnt showing that they are vty connections)
... they must both be considered 'console' connections outbound and are not considered 'vty' until they are received inbound
the asterisk means something different here than above... doesnt mean default(most recent)session... what does it mean?
back to R2
R2#
show users
Line User Host(s) Idle Location
* 4 vty 0 idle 00:00:00 193.1.1.1
Interface User Mode Idle Peer Address
this is saying that there is one (unnamed) user remoted in via line vty 4
back to R3
R3#
show users
Line User Host(s) Idle Location
* 4 vty 0 idle 00:00:00 193.1.1.1
Interface User Mode Idle Peer Address
this is saying that there is one (unnamed) user remoted in via line vty 4
-------------------------------------------------------------------------------------
Important Considerations:
-
asterisk indicates default session
-
when telnetting in, you will be in user mode. If there is no password already set for PRIVILEGED MODE, you will be unable to enter
-
be careful with 'exit'. it will exit the telnet session if you exit at priv. mode. Use 'disable' to leave priv mode.
-
after 'suspending' a session with ctrl+shift+6,x and youre back at your original priv. prompt, do not press enter to create line breaks-
rather than break lines as usual, the keystroke will cause this:
[Resuming connection 1 to 193.1.1.2 ... ]
prompt will sit here until you strike enter again, then you'll return to that session. What is actually happening is that
youre connecting to the 'default' telnet connection. The same behavior happens when youre at the 'show sessions' screen.
Even if you are not viewing active sessions, the enter key(twice) will connect you to the default session
-
you can use disconnect or exit to end a session
-
Ex: disconnect 1 at the show sessions screen
Chapter 7 Hands-on Lab 7.6 Resolving Hostnames
We're going to build a host table on R1 so we can connect to the other routers via hostname rather than type in the IP address
the command is ip host name arg ip arg
R1(config)#
ip host R2 193.1.1.2
R1(config)#
ip host R3 193.1.1.3
Now if we enter R2 or telnet R2 we get the telnet prompt
R1# R2
Trying 193.1.1.2 ...Open
User Access Verification
Password:
same for the PING command
R1# ping R2
Type escape sequence to abort.
Sending 5, 100-byte ICMP Echos to 193.1.1.2, timeout is 2 seconds:
!!!!!
Success rate is 100 percent (5/5), round-trip min/avg/max = 0/0/2 ms
R1#
show hosts
Default Domain is not set
Name/address lookup uses domain service
Name servers are 255.255.255.255
Codes: UN - unknown, EX - expired, OK - OK, ?? - revalidate
temp - temporary, perm - permanent
NA - Not Applicable None - Not defined
Host Port Flags Age Type Address(es)
R2 None (perm, OK) 0 IP 193.1.1.2
R3 None (perm, OK) 0 IP 193.1.1.3
R1#
telnet R2
R2>
CTRL + SHIFT + 6, X
R1#
telnet R3
R3>
CTRL + SHIFT + 6, X
R1#
show session
Conn Host Address Byte Idle Conn Name
1 R2 193.1.1.2 0 0 R2
* 2 R3 193.1.1.3 0 0 R3
Chapter 7 Review Questions
1. What does the command
confreg 0x2142
provide?
bypass startup-config, to allow password reset
2. Which command will copy the IOS to a backup host on your network?
copy flash tftp
3. You are troubleshooting a connectivity problem in your corporate network and want to isolate the problem. You suspect that a router on the route to an unreachable
network is at fault. What IOS user exec command should you issue?
traceroute
note this is not a priviliged mode command; it can be run from user mode
4. You copy a configuration from a network host to a router's RAM. The configuration looks correct, yet it is no working at all. What could the problem be?
when you perform a copy from a network host to a router, the interfaces are automatically shut down and have to be manually enabled with no shutdown
5. A network administrator wants to upgrade the IOS of a router without removing the image currently installed. What command will display the amount of memory consumed by the
current IOS image and indicate whether there is enough room available to hold both the current and new images?
show flash
6. The corporate office sends you a new router to connect, but upon connecting the console cable, you see that there is already a configuration on the router.
What should be done before a new configuration is entered in the router?
erase NVRAM and restart the router
erase startup-config
reload
7. Which command loads a new version of the Cisco IOS into a router?
copy tftp flash
8. Which command will show you the IOS version running on your router?
show version
9. What should the configuration register value be after you successfully complete the password recovery procedure and return the router to normal operation?
0x2102
10. You save the configuration on a router with the
copy running-config startup-config
command and reboot the router. The router, however, comes up with a blank configuration. What can the problem be?
wrong config register causing you to bypass startup-confing in NVRAM
11. If you want to have more than one Telnet session open at the same time, what keystroke combination would you use?
CTRL+SHIFT+6, X
12. You are unsuccessful in telnetting into a remote device, but you could telnet to the router earlier, However, you can still ping the remote device.
What can the problem be?
access control list could be filtering telnet
OR
the VTY password may not be set on the target
13. What information is displayed by the
show hosts
command?
gives info on temporary DNS entries and permanent name-to-address mappings created using the ip host command
14. Name three commands that can be used to check LAN connectivity problems on a router?
trace
show interfaces
show ip route
15. You telnet to a router and make your necessary changes; now you want to end the Telnet session. What command do you type in?
exit
16. You telnet into a remote device and type
debug ip rip
but no output from the
debug
command is seen. What could the problem be?
to see console messages through a telnet session, you must enter the command terminal monitor
17. Which command displays the configuration register setting?
show version
18. You need to gather the IP address of a remote switch that is located in Hawaii. What can you do to find the address?
show cdp neighbors detail
19. You have your laptop directly connected into a router's Ethernet port. Which are requirements for the
copy flash tftp
command to be successful?
have a TFTP server running on the laptop
laptop must have an IP on the same subnet as the router interface
give the IP address of the laptop when asked after entering the command
20. The configuration register setting of 0x2102 provides what function to a router?
points to NVRAM for startup-configuration AND boot sequence
END CHAPTER 7
26 hours 1-19 thru 1-26-22
original total hours 89
7 hours review 12-23-22
review total hours 20.5
book page 344/822
avg 15 min/page (reading and exercises/labs)
Chapter 8 Exercises
pg 374
before I begin to configure this network, I want to look closer at the HARDWARE
Todd mentions these routers:
2811 with four serial interfaces and switch module or wireless card
1841
while the book was published in 2011, both routers appear to be available in 2021 packet tracer,
but both are considered legacy as of Feb 2022.
The 2811:
The 1841:
we're going to need to understand the MODULES. What are these?
a few examples:
NM-1E is a 1-port ethernet module
NM-1FE-TX is a fast ethernet module
NM-8A/s is an Eight Port Async/Sync Network Module
HWIC-2T is a 2-port serial WAN interface card
HWIC-AP-AG-B is a wireless card
What is an "NM module"?
A network module is a software module that implements a specific
function in a network stack, such as a data link interface, a transport protocol,
or a network application.
What is a "HWIC module"?
A high-speed WAN interface card
Here is a look inside a real 2811:
Back to the requirements for our lab- Todd says the 2811 'Corp' router needs a switch module
and four serial interfaces. NOTE the book doesnt give specifics on how to create the topology in Packet Tracer.
Our Packet Tracer 2811 offers these modules:
The NM-ESW-16 appears to be the only 'switch module', so I will add that.
And the HWIC-2T is a 2-Port Serial High-Speed WAN Interface Card, providing 2 serial ports.
I will add two of these.
next: R3, which needs to be a 2811 with a wirless card. I will add the HWIC-AP-AG-B:
The HWIC-AP-AG-B module is a High-Speed WAN Interface Card providing integrated Access Point
functionality in the Cisco 1800 (Modular), Cisco 2800,
and Cisco 3800 Integrated Services Routers.
It supports Single Band 802.11b/g or Dual Band 802.11a/b/g radios.
our router hardware is in place:
and here is where we need to end up
Next we need to figure out how to connect the server farm to the switch card on R1:
if I use the auto-select cable, I get a copper crossover cable connecting at fa0/0 on the router.
Per the diagram fa0/0 should
connect to R3. I need to connect the servers to the switch card on R1.
Instead of using the auto-select cable, I'll try a straight-through cable.
Success. While the auto-select cable did not give me an option as to what port it will connect to, I did get the option when
manually applying the straight-through cable. Instead of connecting to F0/0 which would require a crossover-cable(computer to router),
I will connect to the integrated switch at port F1/0, then connect the other two servers to F1/1 and F1/2, respectively.
Also worth noting: the Physical Device diagrams in Packet Tracer do not show cables plugged into the ports.
We are relying on the labels on the logical diagram to see which cables are plugged into which ports...
As far as how we can tell what is connected from within the CLI.. I dont know right now.
Now I will connect the other routers. Here is the chart specifiying what interfaces should be used:
Router
Network Address
Interface
Address
CORP
10.1.1.0
Vlan1 (switch card)
10.1.1.1
10.1.2.0
S0/0/0
10.1.2.1
10.1.3.0
S0/0/1 (DCE)
10.1.3.1
10.1.4.0
S0/1/0
10.1.4.1
10.1.5.0
F0/0
10.1.5.1
R1
10.1.2.0
S0/0/0 (DCE)
10.1.2.2
10.1.3.0
S0/0/1
10.1.3.2
192.168.10.0
F0/0
192.168.10.1
192.168.20.0
F0/1
192.168.20.1
R2
10.1.4.0
S0/0/0 (DCE)
10.1.4.2
192.168.30.0
F0/0
192.168.30.1
192.168.40.0
F0/0
192.168.40.1
R3
10.1.5.0
F0/0
10.1.5.2
172.16.10.0
Dot11Radio0/0/0
172.16.10.1
PROBLEM
The R1 router doesnt appear to have any serial interfaces
I will add an HWIC-2T card to both R1 and R2 since the diagram calls for serial interfaces.
The HWIC-2T is a Cisco 2-Port Serial High-Speed WAN Interface Card, providing 2 serial ports.
PROBLEM
The Corp router is not showing the expected available interfaces. I need to connect R1 to the S0/0/0 interface on Corp and R2 to the S0/0/1 interface on Corp.
My Corp router is not showing those interfaces:
Solution
the placement of the cards on the router determines which interface numbers will be available.
In this case, it seems the interfaces start from the bottom right corner and increase on each slot moving clockwise. I found this out by filling all four slots on my router
which led to all interfaces being available. I then ran a card in each slot individually to isolate which interface numbers correspond to each slot:
Interestingly, while the physical slots seem to follow a 'clockwise' pattern, the list of available slots in the logical diagram does not;
We get an output of interfaces corresponding to slot 2, then 3, 1, and 4. This is a 'bottom to top' then 'left to right' pattern. Tricky.
Having said all that... I will run cards in slots 1 and 2 for this lab since we only need interfaces S0/0/0, S0/0/1, S0/1/0
The Router topology:
I'm not clear on the connections from R1 and R2 to the clients.. I assume there are switches involved.
For now I will follow the next steps in the book which
are to configure the corp router as follows:
Router(config)#
hostname Corp
Corp(config)#
enable secret todd
Corp(config)#
interface vlan 1
Corp(config-if)#
description Switch Card to Core Network
Corp(config-if)#
ip address 10.1.1.1 255.255.255.0
Corp(config-if)#
no shut
----------------------------------------------------------------------------------------------------------------
Corp(config-if)#
int f1/0
Corp(config-if)#
description Switch Port connection to WWW Server
Corp(config-if)#
no shutdown
Corp(config-if)#
int f1/1
Corp(config-if)#
description Switch Port connection to Email Server
Corp(config-if)#
no shutdown
Corp(config-if)#
int f1/2
Corp(config-if)#
description Switch Port connection to DNS Server
Corp(config-if)#
no shutdown
----------------------------------------------------------------------------------------------------------------
Corp(config-if)#
int s0/0/0
Corp(config-if)#
description 1st Connection to R1
Corp(config-if)#
ip address 10.1.2.1 255.255.255.0
Corp(config-if)#
no shut
Corp(config-if)#
int s0/0/1
Corp(config-if)#
description 2nd Connection to R1
Corp(config-if)#
ip address 10.1.3.1 255.255.255.0
Corp(config-if)#
no shut
Corp(config-if)#
int s0/1/0
Corp(config-if)#
description Connection to R2
Corp(config-if)#
ip address 10.1.4.1 255.255.255.0
Corp(config-if)#
no shut
Corp(config-if)#
int fa0/0
Corp(config-if)#
description Connection to R3
Corp(config-if)#
ip address 10.1.5.1 255.255.255.0
Corp(config-if)#
no shut
----------------------------------------------------------------------------------------------------------------
Corp(config-if)#
line con 0
Corp(config-if)#
password console
Corp(config-if)#
login
Corp(config-if)#
logging synchro
Corp(config-if)#
exec-timeout 0 0
----------------------------------------------------------------------------------------------------------------
Corp(config-if)#
line aux 0
Corp(config-if)#
password aux
Corp(config-if)#
login
Corp(config-if)#
exit
----------------------------------------------------------------------------------------------------------------
Corp(config)#
line vty ?
<1-15>Last Line number
Corp(config)#
line vty 0 15
Corp(config-if)#
password telnet
Corp(config-if)#
login
Corp(config-if)#
exit
----------------------------------------------------------------------------------------------------------------
Corp(config)#
no ip domain lookup
Corp(config)#
banner motd # This is my Corp 2811 ISR Router #
Ctrl + Z
%SYS-5-CONFIG_I: Configured from console by console
(Ctrl-Z: When in a config mode, ends the config mode and returns you to privileged EXEC mode.... same as typing exit(?))
Corp#
copy run start
Destination filename [startup-config]?
Building configuration...
[OK]
----------------------------------------------------------------------------------------------------------------
Corp#
show ip int br
Interface IP-Address OK? Method Status Protocol
FastEthernet0/0 10.1.5.1 YES manual up down
FastEthernet0/1 unassigned YES unset administratively down down
Serial0/0/0 10.1.2.1 YES manual down down
Serial0/0/1 10.1.3.1 YES manual down down
Serial0/1/0 10.1.4.1 YES manual down down
Serial0/1/1 unassigned YES unset administratively down down
FastEthernet1/0 unassigned YES unset up up
FastEthernet1/1 unassigned YES unset up up
FastEthernet1/2 unassigned YES unset up up
FastEthernet1/3 unassigned YES unset administratively down down
FastEthernet1/4 unassigned YES unset administratively down down
FastEthernet1/5 unassigned YES unset administratively down down
FastEthernet1/6 unassigned YES unset administratively down down
FastEthernet1/7 unassigned YES unset administratively down down
FastEthernet1/8 unassigned YES unset administratively down down
FastEthernet1/9 unassigned YES unset administratively down down
FastEthernet1/10 unassigned YES unset administratively down down
FastEthernet1/11 unassigned YES unset administratively down down
FastEthernet1/12 unassigned YES unset administratively down down
FastEthernet1/13 unassigned YES unset administratively down down
FastEthernet1/14 unassigned YES unset administratively down down
FastEthernet1/15 unassigned YES unset administratively down down
Vlan1 10.1.1.1 YES manual up up
----------------------------------------------------------------------------------------------------------------
Corp#
show run
Building configuration...
Current configuration : 2073 bytes
!
version 15.1
no service timestamps log datetime msec
no service timestamps debug datetime msec
no service password-encryption
!
hostname Corp
!
!
!
enable secret 5 $1$mERr$V5ujdIM9bTB/I.ipB0gkJ0
!
!
!
!
!
!
no ip cef
no ipv6 cef
!
!
!
!
license udi pid CISCO2811/K9 sn FTX1017U440-
!
!
!
!
!
!
!
!
!
no ip domain-lookup
!
!
spanning-tree mode pvst
!
!
!
!
!
!
interface FastEthernet0/0
description connection to R3
ip address 10.1.5.1 255.255.255.0
duplex auto
speed auto
!
interface FastEthernet0/1
no ip address
duplex auto
speed auto
shutdown
!
interface Serial0/0/0
description 1st connection to R1
ip address 10.1.2.1 255.255.255.0
clock rate 2000000
!
interface Serial0/0/1
description 2nd connection to R1
ip address 10.1.3.1 255.255.255.0
clock rate 2000000
!
interface Serial0/1/0
description connection to R2
ip address 10.1.4.1 255.255.255.0
!
interface Serial0/1/1
no ip address
clock rate 2000000
shutdown
!
interface FastEthernet1/0
description switch port connection to WWW Server
!
interface FastEthernet1/1
description switch port connection to Email Server
!
interface FastEthernet1/2
description switch port connection to DNS Server
!
interface FastEthernet1/3
shutdown
!
interface FastEthernet1/4
shutdown
!
interface FastEthernet1/5
shutdown
!
interface FastEthernet1/6
shutdown
!
interface FastEthernet1/7
shutdown
!
interface FastEthernet1/8
shutdown
!
interface FastEthernet1/9
shutdown
!
interface FastEthernet1/10
shutdown
!
interface FastEthernet1/11
shutdown
!
interface FastEthernet1/12
shutdown
!
interface FastEthernet1/13
shutdown
!
interface FastEthernet1/14
shutdown
!
interface FastEthernet1/15
shutdown
!
interface Vlan1
description Switch Card to Core Network
ip address 10.1.1.1 255.255.255.0
!
ip classless
!
ip flow-export version 9
!
!
!
banner motd ^C This is my Corp 2811 ISR Router ^C
!
!
!
!
!
line con 0
exec-timeout 0 0
password console
logging synchronous
login
!
line aux 0
password aux
login
!
line vty 0 4
password telnet
login
line vty 5 15
password telnet
login
!
!
!
end
-----------------------------------------------------------------------------------------------------------------------
more configurations:
R1
Router(config)#
hostname R1
R1(config)#
enable secret todd
R1(config)#
int s0/0/0
R1(config-if)#
ip address 10.1.2.2 255.255.255.0
R1(config-if)#
Decription 1st connection to corp router
R1(config-if)#
no shut
-----------------------------------------------------------------------------------------------
R1(config-if)#
int s0/0/1
R1(config-if)#
ip address 10.1.3.2 255.255.255.0
R1(config-if)#
Decription 2nd connection to corp router
R1(config-if)#
no shut
-----------------------------------------------------------------------------------------------
R1(config-if)#
int f0/0
R1(config-if)#
ip address 192.168.10.1 255.255.255.0
R1(config-if)#
Decription connection to finance
R1(config-if)#
no shut
-----------------------------------------------------------------------------------------------
R1(config-if)#
int f0/1
R1(config-if)#
ip address 192.168.20.1 255.255.255.0
R1(config-if)#
Decription connection to marketing
R1(config-if)#
no shut
R1(config-if)#
exit
-----------------------------------------------------------------------------------------------
R1(config)#
line con 0
R1(config-line)#
password console
R1(config-line)#
login
R1(config-line)#
logging synchronous
R1(config-line)#
exec-timeout 0 0
-----------------------------------------------------------------------------------------------
R1(config-line)#
line aux 0
R1(config-line)#
password aux
R1(config-line)#
login
R1(config-line)#
exit
-----------------------------------------------------------------------------------------------
R1(config)#
line vty 0 ?
<0-15> Last Line number
R1(config)#
line vty 0 807
R1(config-line)#
password telnet
R1(config-line)#
login
R1(config-line)#
banner motd # This is my R1 Router #
R1(config-line)#
exit
-----------------------------------------------------------------------------------------------
R1(config)#
no ip domain-lookup
R1(config)#
exit
R1#
copy run start
R2
Router(config)#
hostname R2
R2(config)#
enable secret todd
R2(config)#
int s0/0/0
R2(config-if)#
ip address 10.1.4.2 255.255.255.0
R2(config-if)#
description connection to corp router
R2(config-if)#
no shut
-----------------------------------------------------------------------------------------------
R2(config-if)#
int f0/0
R2(config-if)#
ip address 192.168.30.1 255.255.255.0
R2(config-if)#
description connection to sales PC
R2(config-if)#
no shut
-----------------------------------------------------------------------------------------------
R2(config-if)#
int f0/1
R2(config-if)#
ip address 192.168.40.1 255.255.255.0
R2(config-if)#
description connection to HR pc
R2(config-if)#
no shut
-----------------------------------------------------------------------------------------------
R2(config-if)#
line con 0
R2(config-line)#
password console
R2(config-line)#
login
R2(config-line)#
logging synchronous
R2(config-line)#
exec-timeout 0 0
-----------------------------------------------------------------------------------------------
R2(config-line)#
line aux 0
R2(config-line)#
password aux
R2(config-line)#
login
R2(config-line)#
exit
-----------------------------------------------------------------------------------------------
R2(config)#
line vty 0 ?
<0-15> Last Line number
R2(config)#
line vty 0 807
R2(config-line)#
password telnet
R2(config-line)#
login
R2(config-line)#
banner motd # This is my R1 Router #
R2(config-line)#
exit
-----------------------------------------------------------------------------------------------
R2(config)#
no ip domain-lookup
R2(config)#
exit
R2#
copy run start
R3
Router(config)#
hostname R3
R3(config)#
enable secret todd
R3(config)#
int f0/0
R3(config-if)#
ip address 10.1.5.2 255.255.255.0
R3(config-if)#
description connection to corp router
R3(config-if)#
no shut
-----------------------------------------------------------------------------------------------
R3(config-if)#
int dot11radio0/0/0
R3(config-if)#
ip address 172.16.10.1 255.255.255.0
R3(config-if)#
description WLAN for mobile user
R3(config-if)#
no shut
R3(config-if)#
ssid ADMIN
stuck here 2-5-22-- packet tracer isnt taking me into the config-if-ssid prompt
R3(config-if-ssid)#
guest-mode
R3(config-if-ssid)#
authentication open
R3(config-if-ssid)#
ingrastructure-ssid
R3(config-if-ssid)#
exit
-----------------------------------------------------------------------------------------------
R3(config-if)#
line con 0
R3(config-line)#
password console
R3(config-line)#
login
R3(config-line)#
logging synchronous
R3(config-line)#
exec-timeout 0 0
-----------------------------------------------------------------------------------------------
R3(config-line)#
line aux 0
R3(config-line)#
password aux
R3(config-line)#
login
R3(config-line)#
exit
-----------------------------------------------------------------------------------------------
R3(config)#
line vty 0 ?
<0-15> Last Line number
R3(config)#
line vty 0 807
R3(config-line)#
password telnet
R3(config-line)#
login
R3(config-line)#
banner motd # This is my R1 Router #
R3(config-line)#
exit
-----------------------------------------------------------------------------------------------
R3(config)#
no ip domain-lookup
R3(config)#
exit
R3#
copy run start
PROBLEM
i cant get into conf-if-ssid prompt
R3(config-if)#
ssid ADMIN
%LINK-5-CHANGED: Interface Dot11Radio0/0/0, changed state to administratively down
%LINEPROTO-5-UPDOWN: Line protocol on Interface Dot11Radio0/0/0, changed state to down
%LINK-5-CHANGED: Interface Dot11Radio0/0/0, changed state to up
%LINEPROTO-5-UPDOWN: Line protocol on Interface Dot11Radio0/0/0, changed state to up
R3(config-if)#
research led me to this thread, which is a dead end:
further research led me here:
R3(config)# global config mode
R3(config)#
dot11 ssid ADMIN
creates an SSID or lets you config an existing SSID
R3(config-ssid)#
guest-mode
R3(config-ssid)#
%LINK-5-CHANGED: Interface Dot11Radio0/0/0, changed state to administratively down
%LINEPROTO-5-UPDOWN: Line protocol on Interface Dot11Radio0/0/0, changed state to down
%LINK-5-CHANGED: Interface Dot11Radio0/0/0, changed state to up
%LINEPROTO-5-UPDOWN: Line protocol on Interface Dot11Radio0/0/0, changed state to up
R3(config-ssid)#
authentication open
R3(config-ssid)#
%LINK-5-CHANGED: Interface Dot11Radio0/0/0, changed state to administratively down
%LINEPROTO-5-UPDOWN: Line protocol on Interface Dot11Radio0/0/0, changed state to down
%LINK-5-CHANGED: Interface Dot11Radio0/0/0, changed state to up
%LINEPROTO-5-UPDOWN: Line protocol on Interface Dot11Radio0/0/0, changed state to up
R3(config-ssid)#
infrastructure-ssid
R3(config-ssid)#infrastructure-ssid
^
% Invalid input detected at '^' marker.
this command given by the book doesnt appear to be valid
R3(config-ssid)#
?
authentication authentication method
exit Exit from ssid sub mode
guest-mode guest ssid
no Negate a command or set it's defaults
wpa-psk Configure Wi-Fi Protected Access pre-shared key
back into the interface to see what the options are
R3(config-ssid)#
int dot110/0/0
R3(config-if)#
?
arp Set arp type (arpa, probe, snap) or timeout or log options
bandwidth Set bandwidth informational parameter
cdp CDP interface subcommands
crypto Encryption/Decryption commands
delay Specify interface throughput delay
description Interface specific description
encryption Configure dot11 encryption parameters
exit Exit from interface configuration mode
fair-queue Enable Fair Queuing on an Interface
hold-queue Set hold queue depth
ip Interface Internet Protocol config commands
mac-address Manually set interface MAC address
mtu Set the interface Maximum Transmission Unit (MTU)
no Negate a command or set its defaults
priority-group Assign a priority group to an interface
service-policy Configure QoS Service Policy
shutdown Shutdown the selected interface
speed Set allowed radio bit rates
ssid Configure radio service set parameters
tx-ring-limit Configure PA level transmit ring limit
i'll consider the problem *mostly* solved. I was able to assign the SSD.
The infrastructure command may be expendable in this case... to be determined
here is our configuration for R3
R3#
show run
Building configuration...
Current configuration : 1682 bytes
!
version 15.1
no service timestamps log datetime msec
no service timestamps debug datetime msec
no service password-encryption
!
hostname R3
!
!
!
enable secret 5 $1$mERr$V5ujdIM9bTB/I.ipB0gkJ0
!
!
ip dhcp excluded-address 172.16.10.1 172.16.10.10
!
ip dhcp pool Admin
network 172.16.10.0 255.255.255.0
default-router 172.16.10.1
!
dot11 ssid ADMIN
authentication open
guest-mode
!
dot11 ssid ADMIN2
authentication open
guest-mode
!
!
!
ip cef
no ipv6 cef
!
!
!
!
license udi pid CISCO2811/K9 sn FTX1017RE40-
!
!
!
!
!
!
!
!
!
no ip domain-lookup
ip name-server 172.16.10.4
!
!
spanning-tree mode pvst
!
!
!
!
!
!
interface FastEthernet0/0
description connection to corp router
ip address 10.1.5.2 255.255.255.0
duplex auto
speed auto
!
interface FastEthernet0/1
no ip address
duplex auto
speed auto
shutdown
!
interface Dot11Radio0/0/0
description WAN for mobile
ip address 172.16.10.1 255.255.255.0
speed 12.0 18.0 24.0 36.0 48.0 54.0 6.0 9.0 basic-1.0 basic-11.0 basic-2.0 basic-5.5
ssid ADMIN2
!
interface Dot11Radio0/0/1
no ip address
speed 18.0 36.0 48.0 54.0 9.0 basic-12.0 basic-24.0 basic-6.0
!
interface Serial0/1/0
no ip address
clock rate 2000000
!
interface Serial0/1/1
no ip address
clock rate 2000000
!
interface Vlan1
no ip address
shutdown
!
router rip
version 2
network 10.0.0.0
network 172.16.0.0
!
ip classless
ip route 0.0.0.0 0.0.0.0 10.1.5.1
!
ip flow-export version 9
!
!
!
banner motd ^C this is R3 $
this is R3 ^C
!
!
!
!
!
line con 0
exec-timeout 0 0
password console
logging synchronous
login
!
line aux 0
password aux
login
!
line vty 0 4
password telnet
login
line vty 5 15
password telnet
login
!
!
!
end
to summarize...
the book is a little off here.
-----------------------------------------------------------------------------------------------
R3(config-if)#
int dot11radio0/0/0
R3(config-if)#
ip address 172.16.10.1 255.255.255.0
R3(config-if)#
description WLAN for mobile user
R3(config-if)#
no shut
at this point we have created a wireless interface with an IP address but no SSID exists on this router
interface Dot11Radio0/0/0
description test router 2
ip address 172.16.10.1 255.255.255.0
speed 12.0 18.0 24.0 36.0 48.0 54.0 6.0 9.0 basic-1.0 basic-11.0 basic-2.0 basic-5.5
Trying to use the command "ssid ADMIN" doesnt work here. The below commands are invalid here:
R3(config-if)#
ssid ADMIN
R3(config-if-ssid)#
guest-mode
R3(config-if-ssid)#
authentication open
R3(config-if-ssid)#
ingrastructure-ssid
R3(config-if-ssid)#
exit
-----------------------------------------------------------------------------------------------
We need to drop out of config-if, back to config, and enter SSID config mode
-----------------------------------------------------------------------------------------------
R3(config-if)#
exit
R3(config)#
dot11 ssid ADMIN2 creates an ssid named ADMIN2, and puts us into SSID config mode
R3(config-ssid)#
guest-mode
R3(config-ssid)#
authentication open
then out of config-ssid and back to interface config
R3(config-ssid)#
exit
R3(config)
int dot11r0/0/0
R3(config-if)
?
arp Set arp type (arpa, probe, snap) or timeout or log options
bandwidth Set bandwidth informational parameter
cdp CDP interface subcommands
crypto Encryption/Decryption commands
delay Specify interface throughput delay
description Interface specific description
encryption Configure dot11 encryption parameters
exit Exit from interface configuration mode
fair-queue Enable Fair Queuing on an Interface
hold-queue Set hold queue depth
ip Interface Internet Protocol config commands
mac-address Manually set interface MAC address
mtu Set the interface Maximum Transmission Unit (MTU)
no Negate a command or set its defaults
priority-group Assign a priority group to an interface
service-policy Configure QoS Service Policy
shutdown Shutdown the selected interface
speed Set allowed radio bit rates
ssid Configure radio service set parameters
tx-ring-limit Configure PA level transmit ring limit
we have the option for ssid
R3(config-if)
ssid ADMIN2
%LINK-5-CHANGED: Interface Dot11Radio0/0/0, changed state to administratively down
%LINEPROTO-5-UPDOWN: Line protocol on Interface Dot11Radio0/0/0, changed state to down
%LINK-5-CHANGED: Interface Dot11Radio0/0/0, changed state to up
%LINEPROTO-5-UPDOWN: Line protocol on Interface Dot11Radio0/0/0, changed state to up
the router resets the interface..
-----------------------------------------------------------------------------------------------
R3(config-if)
do show run
[cut]
!
!
dot11 ssid ADMIN2
authentication open
guest-mode
!
!
[cut]
!
interface Dot11Radio0/0/0
description test router 2
ip address 172.16.10.1 255.255.255.0
speed 12.0 18.0 24.0 36.0 48.0 54.0 6.0 9.0 basic-1.0 basic-11.0 basic-2.0 basic-5.5
ssid ADMIN2
!
[cut]
the SSID is created and assigned to the interface
To summarize.
Wrong: create the dot11 interface, then create the SSID from CONFIG-IF mode, which puts you into CONFIG-IF-SSID (there is no such mode on this router) mode, then modify the ssid from there...
Correct: create the dot11 interface. Exit CONFIG-IF and go back to GLOBAL CONFIG. Create the SSID which puts you in CONFIG-SSID mode.
Configure the ssid. Then exit CONFIG-SSID. Back into CONFIG-IF, assign the SSID
We have one more task for R3- Configuring the DHCP pool for wireless clients.
R3(config)#
ip dhcp pool Admin creating the pool name as "Admin"
R3(dhcp-config)#
network 172.16.10.0 255.255.255.0
R3(dhcp-config)#
default-router 172.16.10.1 aka default-gateway for clients in the pool
R3(dhcp-config)#
ip name-server 172.16.10.4 dns server
*automatically exits dhcp-config prompt*
R3(config)#
ip dhcp excluded-address 172.16.10.1 172.16.10.10 excludes the range given
172.16.10.1 is the router interface- we need to specifically exclude it from the pool
this setup should allow the wireless client to pick up an IP after connecting to the open SSID.
However, I was having trouble at first-
even though I seemed to have the SSID set correctly, i was hitting a WEP password prompt
i didnt see any obvious issues with the wifi module im using on the laptop:
The Linksys-WPC300N module provides one 2.4GHz wireless interface suitable for connection to wireless networks.
The module supports protocols that use Ethernet for LAN access.
I ended up creating a new SSID, with the same settings as the original:
R3(config)#
dot11 ssid ADMIN2
R3(config-ssid)#
guest-mode
R3(config-ssid)#
authentication open
and then I assigned the ip address to ssid ADMIN2 instead of the orginal ADMIN ssid
R3(config)#
int dot110/0/0
R3(config-if)#
ip address 172.16.10.1 255.255.255.0
R3(config-if)#
description WLAN for mobile user
R3(config-if)#
no shut
R3(config-if)#
ssid ADMIN2
R3#
show run
Building configuration...
Current configuration : 1467 bytes
!
version 15.1
no service timestamps log datetime msec
no service timestamps debug datetime msec
no service password-encryption
!
hostname R3
!
!
!
enable secret 5 $1$mERr$V5ujdIM9bTB/I.ipB0gkJ0
!
!
ip dhcp excluded-address 172.16.10.1 172.16.10.10
!
ip dhcp pool Admin
network 172.16.10.0 255.255.255.0
default-router 172.16.10.1
!
dot11 ssid ADMIN
authentication open
guest-mode
!
dot11 ssid ADMIN2
authentication open
guest-mode
!
!
!
ip cef
no ipv6 cef
!
!
!
!
license udi pid CISCO2811/K9 sn FTX1017RE40-
!
!
!
!
!
!
!
!
!
no ip domain-lookup
ip name-server 172.16.10.4
!
!
spanning-tree mode pvst
!
!
!
!
!
!
interface FastEthernet0/0
description connection to corp router
ip address 10.1.5.2 255.255.255.0
duplex auto
speed auto
!
interface FastEthernet0/1
no ip address
duplex auto
speed auto
shutdown
!
interface Dot11Radio0/0/0
description WAN for mobile
ip address 172.16.10.1 255.255.255.0
speed 12.0 18.0 24.0 36.0 48.0 54.0 6.0 9.0 basic-1.0 basic-11.0 basic-2.0 basic-5.5
ssid ADMIN2
!
interface Dot11Radio0/0/1
no ip address
speed 18.0 36.0 48.0 54.0 9.0 basic-12.0 basic-24.0 basic-6.0
!
interface Vlan1
no ip address
shutdown
!
ip classless
!
ip flow-export version 9
!
!
!
banner motd ^C this is R3 $
this is R3 ^C
!
!
!
!
!
line con 0
exec-timeout 0 0
password console
logging synchronous
login
!
line aux 0
password aux
login
!
line vty 0 4
password telnet
login
line vty 5 15
password telnet
login
!
!
!
end
Recall the DHCP configuration on R3:
R3(config)#
ip dhcp pool Admin creating the pool name as "Admin"
R3(dhcp-config)#
network 172.16.10.0 255.255.255.0
R3(dhcp-config)#
default-router 172.16.10.1 aka default-gateway for clients in the pool
R3(dhcp-config)#
ip name-server 172.16.10.4 dns server
*automatically exits dhcp-config prompt*
R3(config)#
ip dhcp excluded-address 172.16.10.1 172.16.10.10 excludes the range given
172.16.10.1 is the router interface- we need to specifically exclude it from the pool
we can check the configuration:
R3#
show ip dhcp pool
Pool Admin :
Utilization mark (high/low) : 100 / 0
Subnet size (first/next) : 0 / 0
Total addresses : 254
Leased addresses : 1
Excluded addresses : 1
Pending event : none
1 subnet is currently in the pool
Current index IP address range Leased/Excluded/Total
172.16.10.1 172.16.10.1 - 172.16.10.254 1 / 1 / 254
R3#
show ip dhcp binding
IP address Client-ID/ Lease expiration Type
Hardware address
172.16.10.11 00D0.979A.733B -- Automatic
the show command is becoming more familiar
R3#
show ip?
access-lists List access lists
arp IP ARP table
bgp BGP information
cache IP fast-switching route cache
cef Cisco Express Forwarding
dhcp Show items in the DHCP database
eigrp IP-EIGRP show commands
inspect CBAC (Context Based Access Control) information
interface IP interface status and configuration
ips IPS (Intrusion Prevention System) information
nat IP NAT information
nbar Network-Based Application Recognition
ospf OSPF information
protocols IP routing protocol process parameters and statistics
rip IP RIP show commands
route IP routing table
ssh Information on SSH
we'll use show ip route soon on all the routers. For now, here is the output for R3:
R3#
show ip route
Codes: L - local, C - connected, S - static, R - RIP, M - mobile, B - BGP
D - EIGRP, EX - EIGRP external, O - OSPF, IA - OSPF inter area
N1 - OSPF NSSA external type 1, N2 - OSPF NSSA external type 2
E1 - OSPF external type 1, E2 - OSPF external type 2, E - EGP
i - IS-IS, L1 - IS-IS level-1, L2 - IS-IS level-2, ia - IS-IS inter area
* - candidate default, U - per-user static route, o - ODR
P - periodic downloaded static route
Gateway of last resort is not set
10.0.0.0/8 is variably subnetted, 2 subnets, 2 masks
C 10.1.5.0/24 is directly connected, FastEthernet0/0
L 10.1.5.2/32 is directly connected, FastEthernet0/0
172.16.0.0/16 is variably subnetted, 2 subnets, 2 masks
C 172.16.10.0/24 is directly connected, Dot11Radio0/0/0
L 172.16.10.1/32 is directly connected, Dot11Radio0/0/0
Before moving on to the routing configurations, here is a review of the topology
I have switched over to the DrawIO diagram app to lay out the topology.
The Packet Tracer diagram becomes
too crowded to see the labels; it's labeling system forces awkward positioning of the objects; the interface
label's cant be moved, so if objects are too close together their labels cover eachother.. not good.
DrawIO allows a cleaner layout with plenty of room to label interfaces and ip addresses.
As a compromise, I'll use both.
I have the packet tracer objects spread out just enough to see the interfaces
and the label for each router. From here I can jump into the CLI for each device.
The DrawIO diagram allows me to cleary see IP addresses
I want to also review all of the configurations we just performed:
PROBLEM
The book specifies that of the two serial conections between R1 and Corp, there should be a DCE on each end..
Both of my DCE's are on the same end.
First lets be sure we understand what DCE means:
networkengineering.stackexchange.com/
One side of the link (DCE), has to transmit the clock signal, which controls the data rate, and the other side (DTE) receives the clock signal.
That is good enough for now. Note that while the book does specify in the diagram that each side should have a DCE, it was not actually mentioned in the configs.
We did not set a DCE or clock rate when conifguring those interfaces.
To fix this in my Packet Tracer topology, I did some quick research:
While this post wasnt pertaining to Packet Tracer, it got me thinking about the cable itself.
I deleted both of my existing serial connections and looked at the options for creating a new cable.
I noticed one is a DCE and one is a DTE:
Fixed the issue
back to the configuration overview: 4 routers, abbreviated show run output
Corp
interface FastEthernet0/0
description connection to R3
ip address 10.1.5.1 255.255.255.0
duplex auto
speed auto
!
interface FastEthernet0/1
no ip address
duplex auto
speed auto
shutdown
!
interface Serial0/0/0
description 1st connection to R1
ip address 10.1.2.1 255.255.255.0
!
interface Serial0/0/1
description 2nd connection to R1
ip address 10.1.3.1 255.255.255.0
clock rate 2000000
!
interface Serial0/1/0
description connection to R2
ip address 10.1.4.1 255.255.255.0
!
interface Vlan1
description Switch Card to Core Network
ip address 10.1.1.1 255.255.255.0
!
interface FastEthernet1/0
description switch port connection to WWW Server
switchport mode access
switchport nonegotiate
!
interface FastEthernet1/1
description switch port connection to Email Server
switchport mode access
switchport nonegotiate
!
interface FastEthernet1/2
description switch port connection to DNS Server
switchport mode access
switchport nonegotiate
!
R1
interface FastEthernet0/0
description connection to Finance
ip address 192.168.10.1 255.255.255.0
duplex auto
speed auto
!
interface FastEthernet0/1
description connection to Marketing
ip address 192.168.20.1 255.255.255.0
duplex auto
speed auto
!
interface Serial0/0/0
description 1st connection to Corp router
ip address 10.1.2.2 255.255.255.0
clock rate 2000000
!
interface Serial0/0/1
description 2nd connecction to Corp router
ip address 10.1.3.2 255.255.255.0
!
R2
interface FastEthernet0/0
description Connection to Sales PC
ip address 192.168.30.1 255.255.255.0
duplex auto
speed auto
!
interface FastEthernet0/1
description Connection to HR PC
ip address 192.168.40.1 255.255.255.0
duplex auto
speed auto
!
interface Serial0/0/0
description Connection to Corp Router
ip address 10.1.4.2 255.255.255.0
clock rate 2000000
!
interface Serial0/0/1
no ip address
clock rate 2000000
shutdown
!
R3
interface FastEthernet0/0
description connection to corp router
ip address 10.1.5.2 255.255.255.0
duplex auto
speed auto
!
interface FastEthernet0/1
no ip address
duplex auto
speed auto
shutdown
!
interface Dot11Radio0/0/0
description WAN for mobile
ip address 172.16.10.1 255.255.255.0
speed 12.0 18.0 24.0 36.0 48.0 54.0 6.0 9.0 basic-1.0 basic-11.0 basic-2.0 basic-5.5
ssid ADMIN2
and here is the output of show ip route for each router
Codes: C - connected, S - static, I - IGRP, R - RIP, M - mobile, B - BGP
D - EIGRP, EX - EIGRP external, O - OSPF, IA - OSPF inter area
N1 - OSPF NSSA external type 1, N2 - OSPF NSSA external type 2
E1 - OSPF external type 1, E2 - OSPF external type 2, E - EGP
i - IS-IS, L1 - IS-IS level-1, L2 - IS-IS level-2, ia - IS-IS inter area
* - candidate default, U - per-user static route, o - ODR
P - periodic downloaded static route
Gateway of last resort is not set
Corp
10.0.0.0/24 is subnetted, 2 subnets
C 10.1.2.0 is directly connected, Serial0/0/0
C 10.1.3.0 is directly connected, Serial0/0/1
C 192.168.10.0/24 is directly connected, FastEthernet0/0
C 192.168.20.0/24 is directly connected, FastEthernet0/1
R1
10.0.0.0/24 is subnetted, 2 subnets
C 10.1.2.0 is directly connected, Serial0/0/0
C 10.1.3.0 is directly connected, Serial0/0/1
C 192.168.10.0/24 is directly connected, FastEthernet0/0
C 192.168.20.0/24 is directly connected, FastEthernet0/1
R2
10.0.0.0/24 is subnetted, 1 subnets
C 10.1.4.0 is directly connected, Serial0/0/0
C 192.168.30.0/24 is directly connected, FastEthernet0/0
C 192.168.40.0/24 is directly connected, FastEthernet0/1
R3
10.0.0.0/8 is variably subnetted, 2 subnets, 2 masks
C 10.1.5.0/24 is directly connected, FastEthernet0/0
L 10.1.5.2/32 is directly connected, FastEthernet0/0
172.16.0.0/16 is variably subnetted, 2 subnets, 2 masks
C 172.16.10.0/24 is directly connected, Dot11Radio0/0/0
L 172.16.10.1/32 is directly connected, Dot11Radio0/0/0
Note that this is before we have configured any 'routing'. We are seeing configured, directly connected networks.
The output for R3 is particularly interesting
What does 'variably' subnetted mean, and what is the "L" next to these routes. And why do they have a mask of 32?
R3
10.0.0.0/8 is variably subnetted, 2 subnets, 2 masks
C 10.1.5.0/24 is directly connected, FastEthernet0/0
L 10.1.5.2/32 is directly connected, FastEthernet0/0
172.16.0.0/16 is variably subnetted, 2 subnets, 2 masks
C 172.16.10.0/24 is directly connected, Dot11Radio0/0/0
L 172.16.10.1/32 is directly connected, Dot11Radio0/0/0
Cisco forums
That makes sense, but my question is why did the other routing tables not behave the same way? R3 is the only one that shows "L" routes.
The book tells us we're using two different model routers, and indeed they are running different IOS versions:
NOTE that at the time the book was published IOS 15 was not released yet, so the book assumes all routers are running 12.4
But that still doesnt explain why Corp and R3 are behaving differently..
Corp
10.0.0.0/24 is subnetted, 2 subnets
C 10.1.2.0 is directly connected, Serial0/0/0
C 10.1.3.0 is directly connected, Serial0/0/1
C 192.168.10.0/24 is directly connected, FastEthernet0/0
C 192.168.20.0/24 is directly connected, FastEthernet0/1
R1
10.0.0.0/24 is subnetted, 2 subnets
C 10.1.2.0 is directly connected, Serial0/0/0
C 10.1.3.0 is directly connected, Serial0/0/1
C 192.168.10.0/24 is directly connected, FastEthernet0/0
C 192.168.20.0/24 is directly connected, FastEthernet0/1
R2
10.0.0.0/24 is subnetted, 1 subnets
C 10.1.4.0 is directly connected, Serial0/0/0
C 192.168.30.0/24 is directly connected, FastEthernet0/0
C 192.168.40.0/24 is directly connected, FastEthernet0/1
R3
10.0.0.0/8 is variably subnetted, 2 subnets, 2 masks
C 10.1.5.0/24 is directly connected, FastEthernet0/0
L 10.1.5.2/32 is directly connected, FastEthernet0/0
172.16.0.0/16 is variably subnetted, 2 subnets, 2 masks
C 172.16.10.0/24 is directly connected, Dot11Radio0/0/0
L 172.16.10.1/32 is directly connected, Dot11Radio0/0/0
how are Corp and R3 different?
The answer is, they are not...
I have accidentally displayed the R1 output to the Corp windows. Error in translating data from the IOS to this webpage..
here's the corrected output.
Corp
10.0.0.0/8 is variably subnetted, 10 subnets, 2 masks
C 10.1.1.0/24 is directly connected, Vlan1
L 10.1.1.1/32 is directly connected, Vlan1
C 10.1.2.0/24 is directly connected, Serial0/0/0
L 10.1.2.1/32 is directly connected, Serial0/0/0
C 10.1.3.0/24 is directly connected, Serial0/0/1
L 10.1.3.1/32 is directly connected, Serial0/0/1
C 10.1.4.0/24 is directly connected, Serial0/1/0
L 10.1.4.1/32 is directly connected, Serial0/1/0
C 10.1.5.0/24 is directly connected, FastEthernet0/0
L 10.1.5.1/32 is directly connected, FastEthernet0/0
R1
10.0.0.0/24 is subnetted, 2 subnets
C 10.1.2.0 is directly connected, Serial0/0/0
C 10.1.3.0 is directly connected, Serial0/0/1
C 192.168.10.0/24 is directly connected, FastEthernet0/0
C 192.168.20.0/24 is directly connected, FastEthernet0/1
R2
10.0.0.0/24 is subnetted, 1 subnets
C 10.1.4.0 is directly connected, Serial0/0/0
C 192.168.30.0/24 is directly connected, FastEthernet0/0
C 192.168.40.0/24 is directly connected, FastEthernet0/1
R3
10.0.0.0/8 is variably subnetted, 2 subnets, 2 masks
C 10.1.5.0/24 is directly connected, FastEthernet0/0
L 10.1.5.2/32 is directly connected, FastEthernet0/0
172.16.0.0/16 is variably subnetted, 2 subnets, 2 masks
C 172.16.10.0/24 is directly connected, Dot11Radio0/0/0
L 172.16.10.1/32 is directly connected, Dot11Radio0/0/0
We do indeed see consistent behavior differences between IOS versions 12.4 and 15.1
recap Corp and R3 outputs:
update topology with Router versions
That covers the first half of Chapter 8. Now we are ready to configure IP routing on our network.
There are three ways: Static, Default, Dynamic
To set up static routes, we simply need to program the routes using the ip route command
Syntax
ip route
[
destination network
]
[
mask
]
[
next hop
]
[
exitinterface
]
[
administrative distance
]
[
permanent
]
destination network and mask
the network data we're adding to the routing table
next-hop address
the address of the next-hop router that will receive the packet and forward to the remote network.
This is the IP address of a router interface that is directly connected.
It must be pingable.
exit interface
can be used instead of next hop address
administrative distance
by default, static routes have an admin distance of 1 if you use a next hop, or 0 if you use exit interface.
You can change the value by adding an administrative weight at the end of the command. More on this later with dynamic routing.
permanent
if the interface is shut down or the router cant communicate to the next hp router, the route will automatically be discarded from the table by default.
The 'permanent' option keeps the entry in the routing table indefenitely.
-----------------------------------------------------------------------------------------------------
Corp has automatically picked up 5 routes that are directly connected:
10.1.1.0 to corp switch card
10.1.2.0 to R1
10.1.3.0 to R1
10.1.4.0 to R2
10.1.5.0 to R3
We need to program 5 more routes:
192.168.10.0 traverse R1
192.168.20.0 traverse R1
192.168.30.0 traverse R1
192.168.40.0 traverse R2
172.16.10.0 traverse R3
-----------------------------------------------------------------------------------------------------
R1 has automatically picked up 4 routes that are directly connected:
10.1.2.0
10.1.3.0
192.168.10.0
192.168.20.0
We need to program 6 more routes:
10.1.1.0
10.1.4.0
10.1.5.0
192.168.30.0
192.168.40.0
172.16.10.0
-----------------------------------------------------------------------------------------------------
R2 has automatically picked up 3 routes that are directly connected:
10.1.4.0
192.168.30.0
192.168.40.0
We need to program 7 more routes:
10.1.1.0
10.1.2.0
10.1.3.0
10.1.5.0
192.168.10.0
192.168.20.0
172.16.10.0
-----------------------------------------------------------------------------------------------------
R3 has automatically picked up 2 routes that are directly connected:
10.1.5.0
172.16.10.0
We need to program 8 more routes:
10.1.1.0
10.1.2.0
10.1.3.0
10.1.4.0
192.168.10.0
192.168.20.0
192.168.30.0
192.168.40.0
Notice the pattern- each router ends up with 10 routes
There are 10 routes total in this topology. AKA ten broadcast domains
Programming the routes
Corp
Corp(config)#
ip route 192.168.10.0 255.255.255.0 10.1.2.2 150
Corp(config)#
ip route 192.168.20.0 255.255.255.0 10.1.3.2 150
Corp(config)#
ip route 192.168.30.0 255.255.255.0 10.1.4.2 150
Corp(config)#
ip route 192.168.40.0 255.255.255.0 10.1.4.2 150
Corp(config)#
ip route 172.16.10.0 255.255.255.0 10.1.5.2 150
Corp(config)#
do show ip route
In the first line, the router is saying that a
classful A network is being subnetted
There are 5 routes directly connected
We see two lines per route (one for the network and one
for the interface(/32)-
10.0.0.0/8 is variably subnetted, 10 subnets, 2 masks
C 10.1.1.0/24 is directly connected, Vlan1
L 10.1.1.1/32 is directly connected, Vlan1
C 10.1.2.0/24 is directly connected, Serial0/0/0
L 10.1.2.1/32 is directly connected, Serial0/0/0
C 10.1.3.0/24 is directly connected, Serial0/0/1
L 10.1.3.1/32 is directly connected, Serial0/0/1
C 10.1.4.0/24 is directly connected, Serial0/1/0
L 10.1.4.1/32 is directly connected, Serial0/1/0
C 10.1.5.0/24 is directly connected, FastEthernet0/0
L 10.1.5.1/32 is directly connected, FastEthernet0/0
and 5 routes that require traversal of a router to reach
172.16.0.0/24 is subnetted, 1 subnets
S 172.16.10.0/24 [150/0] via 10.1.5.2
S 192.168.10.0/24 [150/0] via 10.1.2.2
S 192.168.20.0/24 [150/0] via 10.1.3.2
S 192.168.30.0/24 [150/0] via 10.1.4.2
S 192.168.40.0/24 [150/0] via 10.1.4.2
R1
R1(config)#
ip route 10.1.1.0 255.255.255.0 10.1.2.1 150
R1(config)#
ip route 10.1.4.0 255.255.255.0 10.1.3.1 150
R1(config)#
ip route 10.1.5.0 255.255.255.0 10.1.2.1 150
R1(config)#
ip route 192.168.30.0 255.255.255.0 10.1.3.1 150
R1(config)#
ip route 192.168.40.0 255.255.255.0 10.1.2.1 150
R1(config)#
ip route 172.16.10.0 255.255.255.0 10.1.3.1 150
the only way to get across the corp router is to go into it via 10.1.2.1 or 10.1.3.1
R1(config)#
do show ip route
10.0.0.0/24 is subnetted, 5 subnets
S 10.1.1.0 [150/0] via 10.1.2.1
C 10.1.2.0 is directly connected, Serial0/0/0
C 10.1.3.0 is directly connected, Serial0/0/1
S 10.1.4.0 [150/0] via 10.1.3.1
S 10.1.5.0 [150/0] via 10.1.2.1
172.16.0.0/24 is subnetted, 1 subnets
S 172.16.10.0 [150/0] via 10.1.3.1
C 192.168.10.0/24 is directly connected, FastEthernet0/0
C 192.168.20.0/24 is directly connected, FastEthernet0/1
S 192.168.30.0/24 [150/0] via 10.1.3.1
S 192.168.40.0/24 [150/0] via 10.1.2.1
R2
R2(config)#
iproute 10.1.1.0 255.255.255.0 10.1.4.1 150
R2(config)#
iproute 10.1.2.0 255.255.255.0 10.1.4.1 150
R2(config)#
iproute 10.1.3.0 255.255.255.0 10.1.4.1 150
R2(config)#
iproute 10.1.5.0 255.255.255.0 10.1.4.1 150
R2(config)#
iproute 192.168.10.0 255.255.255.0 10.1.4.1 150
R2(config)#
iproute 192.168.20.0 255.255.255.0 10.1.4.1 150
the only way to get across Corp is to go into it via 10.1.4.1
R2(config)#
do show ip route
10.0.0.0/24 is subnetted, 5 subnets
S 10.1.1.0 [150/0] via 10.1.4.1
S 10.1.2.0 [150/0] via 10.1.4.1
S 10.1.3.0 [150/0] via 10.1.4.1
C 10.1.4.0 is directly connected, Serial0/0/0
S 10.1.5.0 [150/0] via 10.1.4.1
172.16.0.0/24 is subnetted, 1 subnets
S 172.16.10.0 [150/0] via 10.1.4.1
S 192.168.10.0/24 [150/0] via 10.1.4.1
S 192.168.20.0/24 [150/0] via 10.1.4.1
C 192.168.30.0/24 is directly connected, FastEthernet0/0
C 192.168.40.0/24 is directly connected, FastEthernet0/1
R3
R3(config)#
ip route 10.1.1.0 255.255.255.0 fastethernet 0/0 150
R3(config)#
ip route 10.1.2.0 255.255.255.0 fastethernet 0/0 150
R3(config)#
ip route 10.1.3.0 255.255.255.0 fastethernet 0/0 150
R3(config)#
ip route 10.1.4.0 255.255.255.0 fastethernet 0/0 150
R3(config)#
ip route 192.168.10.0 255.255.255.0 fastethernet 0/0 150
R3(config)#
ip route 192.168.20.0 255.255.255.0 fastethernet 0/0 150
R3(config)#
ip route 192.168.30.0 255.255.255.0 fastethernet 0/0 150
R3(config)#
ip route 192.168.40.0 255.255.255.0 fastethernet 0/0 150
the only way to get across Corp is to EXIT R3 via F0/0
R3(config)#
do show ip route
10.0.0.0/8 is variably subnetted, 6 subnets, 2 masks
S 10.1.1.0/24 is directly connected, FastEthernet0/0
S 10.1.2.0/24 is directly connected, FastEthernet0/0
S 10.1.3.0/24 is directly connected, FastEthernet0/0
S 10.1.4.0/24 is directly connected, FastEthernet0/0
C 10.1.5.0/24 is directly connected, FastEthernet0/0
L 10.1.5.2/32 is directly connected, FastEthernet0/0
172.16.0.0/16 is variably subnetted, 2 subnets, 2 masks
C 172.16.10.0/24 is directly connected, Dot11Radio0/0/0
L 172.16.10.1/32 is directly connected, Dot11Radio0/0/0
S 192.168.10.0/24 is directly connected, FastEthernet0/0
S 192.168.20.0/24 is directly connected, FastEthernet0/0
S 192.168.30.0/24 is directly connected, FastEthernet0/0
S 192.168.40.0/24 is directly connected, FastEthernet0/0
before verifying connectivity across the network, we need to make sure all of our hosts are set. The book is giving us the IP addresses for the servers:
Server Gateway 10.1.1.1
ServerWeb 10.1.1.2
ServerEmail 10.1.1.3
ServerDNS 10.1.1.4
Now we can do some testing across the network:
R3#
ping 10.1.2.2
traverse Corp to R1
R3#
ping 10.1.1.1
traverse Corp to a Corp interface we arent directly connected to
R3#
ping 10.1.1.2
traverse Corp to Web server
R3#
ping 10.1.1.3
traverse Corp to Email server
R3#
ping 10.1.1.4
traverse Corp to DNS server
MobileUser
ping 192.168.10.2
traverse R3, Corp, R1 to Finance client
MobileUser
tracert 192.168.10.2
traverse R3, Corp, R1 to Finance client
Tracing route to 192.168.10.2 over a maximum of 30 hops:
1 19 ms 5 ms 20 ms 172.16.10.1
2 20 ms 6 ms 11 ms 10.1.5.1
3 11 ms 15 ms 10 ms 10.1.3.2
4 9 ms 13 ms 22 ms 192.168.10.2
Trace complete.
notice how the trace doesnt count an egress as a hop, only an ingress
ALSO NOTE that tracert is a Windows command.
the IOS equivalent is traceroute
notice how the output differs from the Windows command
R3
traceroute 192.168.10.2
Type escape sequence to abort.
Tracing the route to 192.168.10.2
1 10.1.5.1 0 msec 0 msec 0 msec
2 10.1.2.2 6 msec 0 msec 5 msec
3 192.168.10.2 1 msec 4 msec 3 msec
Default Routing
we could have done this on R3
R3(config)#
ip route 0.0.0.0 0.0.0.0 10.1.5.1
as an alternative to this configuration on R3
R3(config)#
ip route 10.1.1.0 255.255.255.0 fastethernet 0/0 150
R3(config)#
ip route 10.1.2.0 255.255.255.0 fastethernet 0/0 150
R3(config)#
ip route 10.1.3.0 255.255.255.0 fastethernet 0/0 150
R3(config)#
ip route 10.1.4.0 255.255.255.0 fastethernet 0/0 150
R3(config)#
ip route 192.168.10.0 255.255.255.0 fastethernet 0/0 150
R3(config)#
ip route 192.168.20.0 255.255.255.0 fastethernet 0/0 150
R3(config)#
ip route 192.168.30.0 255.255.255.0 fastethernet 0/0 150
R3(config)#
ip route 192.168.40.0 255.255.255.0 fastethernet 0/0 150
the only way to get across Corp is to EXIT R3 via F0/0
This is called default routing. It should only be used on 'stub routers'- those with only one exit path out of the network.
if you try to put a default route on a non-stub router, you could create loops, since there will be more than one path to other routers...
Think of a default route as a static route that uses a wildcard address and mask. The wildcard is 0.0.0.0
to further analyze this comparison, I'm going to remove the routes from R3...
R3(config)#
no ip route 10.1.1.0 255.255.255.0 fastethernet0/0 150
R3(config)#
no ip route 10.1.2.0 255.255.255.0 fastethernet0/0 150
R3(config)#
no ip route 10.1.3.0 255.255.255.0 fastethernet0/0 150
R3(config)#
no ip route 10.1.4.0 255.255.255.0 fastethernet0/0 150
R3(config)#
no ip route 192.168.10.0 255.255.255.0 fastethernet0/0 150
R3(config)#
no ip route 192.168.20.0 255.255.255.0 fastethernet0/0 150
R3(config)#
no ip route 192.168.30.0 255.255.255.0 fastethernet0/0 150
R3(config)#
no ip route 192.168.40.0 255.255.255.0 fastethernet0/0 150
and then set the default route instead.
R3#
ip route 0.0.0.0 0.0.0.0 10.1.5.1 --- ingress at next hop
OR
R3#
ip route 0.0.0.0 0.0.0.0 Fa0/0 --- egress interface
Then compare the output of show ip route
static routes set
R3#
show ip route
Gateway of last resort is not set
10.0.0.0/8 is variably subnetted, 6 subnets, 2 masks
S 10.1.1.0/24 is directly connected, FastEthernet0/0
S 10.1.2.0/24 is directly connected, FastEthernet0/0
S 10.1.3.0/24 is directly connected, FastEthernet0/0
S 10.1.4.0/24 is directly connected, FastEthernet0/0
C 10.1.5.0/24 is directly connected, FastEthernet0/0
L 10.1.5.2/32 is directly connected, FastEthernet0/0
172.16.0.0/16 is variably subnetted, 2 subnets, 2 masks
C 172.16.10.0/24 is directly connected, Dot11Radio0/0/0
L 172.16.10.1/32 is directly connected, Dot11Radio0/0/0
S 192.168.10.0/24 is directly connected, FastEthernet0/0
S 192.168.20.0/24 is directly connected, FastEthernet0/0
S 192.168.30.0/24 is directly connected, FastEthernet0/0
S 192.168.40.0/24 is directly connected, FastEthernet0/0
default route set
R3#
show ip route
Gateway of last resort is 10.1.5.1 to network 0.0.0.0
10.0.0.0/8 is variably subnetted, 2 subnets, 2 masks
C 10.1.5.0/24 is directly connected, FastEthernet0/0
L 10.1.5.2/32 is directly connected, FastEthernet0/0
172.16.0.0/16 is variably subnetted, 2 subnets, 2 masks
C 172.16.10.0/24 is directly connected, Dot11Radio0/0/0
L 172.16.10.1/32 is directly connected, Dot11Radio0/0/0
S* 0.0.0.0/0 [1/0] via 10.1.5.1
two directly connected networks- 10.1.5.0 and 172.16.10.0
anything not included in those networks goes to ingress of attached neighbor Corp 10.1.5.1
in this toplogy, that includes:
192.168.10.0
192.168.20.0
192.168.30.0
192.168.40.0
and
10.1.1.0
10.1.2.0
10.1.3.0
10.1.4.0
RIP Routing Information Protocol
R1(config)#
router ?
bgp Border Gateway Protocol (BGP)
eigrp Enhanced Interior Gateway Routing Protocol (EIGRP)
ospf Open Shortest Path First (OSPF)
rip Routing Information Protocol (RIP)
set RIP on Corp
Corp(config)#
router rip
Corp(config-router)#
network 10.0.0.0
set RIP on R1
R1(config)#
router rip
R1(config-router)#
network 10.0.0.0
R1 routing table
R1(config)#
do show ip route
10.0.0.0/24 is subnetted, 5 subnets
R 10.1.1.0 [120/1] via 10.1.2.1, 00:00:21, Serial0/0/0
[120/1] via 10.1.3.1, 00:00:21, Serial0/0/1
C 10.1.2.0 is directly connected, Serial0/0/0
C 10.1.3.0 is directly connected, Serial0/0/1
R 10.1.4.0 [120/1] via 10.1.2.1, 00:00:21, Serial0/0/0
[120/1] via 10.1.3.1, 00:00:21, Serial0/0/1
R 10.1.5.0 [120/1] via 10.1.2.1, 00:00:21, Serial0/0/0
[120/1] via 10.1.3.1, 00:00:21, Serial0/0/1
172.16.0.0/24 is subnetted, 1 subnets
S 172.16.10.0 [150/0] via 10.1.3.1
C 192.168.10.0/24 is directly connected, FastEthernet0/0
C 192.168.20.0/24 is directly connected, FastEthernet0/1
S 192.168.30.0/24 [150/0] via 10.1.3.1
S 192.168.40.0/24 [150/0] via 10.1.2.1
here's R1 before RIP, with only static routes set:
R1(config)#
do show ip route
10.0.0.0/24 is subnetted, 5 subnets
S 10.1.1.0 [150/0] via 10.1.2.1
C 10.1.2.0 is directly connected, Serial0/0/0
C 10.1.3.0 is directly connected, Serial0/0/1
S 10.1.4.0 [150/0] via 10.1.3.1
S 10.1.5.0 [150/0] via 10.1.2.1
172.16.0.0/24 is subnetted, 1 subnets
S 172.16.10.0 [150/0] via 10.1.3.1
C 192.168.10.0/24 is directly connected, FastEthernet0/0
C 192.168.20.0/24 is directly connected, FastEthernet0/1
S 192.168.30.0/24 [150/0] via 10.1.3.1
S 192.168.40.0/24 [150/0] via 10.1.2.1
These RIP routes are being advertised as available *to other RIP routers*.
CORP is advertisting THREE routes via RIP to R1 right now
10.1.1.0
10.1.4.0
10.1.5.0
access to those networks can be achieved by R1 by going THROUGH CORP via ingress .2.1 or .3.1
The advantage..... is that we didnt statically program these routes
we engaged RIP, on BOTH routers- R1 and Corp, and handed them BOTH the network "10.0.0.0"
So, why did RIP choose to display these particular routes
Keep in mind that the output above is from R1 only... In the context of the R1 ROUTER ONLY,
there are three relevant routes within the "10.0.0.0" parameter we specified. The three routes involve Corp.
Corp is sending RIP data about these routes to Corp.
Lets look closer at how this is happening:
here's our starting point before any RIP is set
here's our routing tables after i set RIP with 10.0.0.0 on both..
FIRST i set it on Corp, then R1.(per the book's instructions) As a result we are seeing RIP routes in R1 only....
then I went back to a fresh packet tracer file with no RIP set. And I set RIP in the opposite order;
FIRST i set it on R1, then Corp. And again, we are seeing RIP routes in R1 only....
I wanted to prove that it didnt matter which order we enabled RIP on the two routers. What matters here is that
we enable RIP on both of them with the criteria of 10.0.0.0
Recall the topology:
if Corp and R1 are set for RIP and given the criteria 10.0.0.0, meaning that we are trying to reach networks
within that range, then it follows that Corp will advertise 1.1.0, 1.4.0, and 1.5.0 to R1, because Corp stands between those networks
and R1
"Hi R1, I'm Corp I have three networks that fall inside 10.0.0.0, and you can reach them through me via .2.1 or .3.1"
It also follows that Corp's routing table shows no RIP routes- because R1 isnt advertising any. R1 doesnt have any networks
in the 10.0.0.0 range that Corp could reach
To further clarify this, we'll proceed with the book's instructions. We'll now set more RIP routes on R1
R1(config)#
router rip
R1(config-router)#
network 192.168.10.0
R1(config-router)#
network 192.168.20.0
Corp routing table before RIP set on R1:
Corp#
show ip route
10.0.0.0/8 is variably subnetted, 10 subnets, 2 masks
C 10.1.1.0/24 is directly connected, Vlan1
L 10.1.1.1/32 is directly connected, Vlan1
C 10.1.2.0/24 is directly connected, Serial0/0/0
L 10.1.2.1/32 is directly connected, Serial0/0/0
C 10.1.3.0/24 is directly connected, Serial0/0/1
L 10.1.3.1/32 is directly connected, Serial0/0/1
C 10.1.4.0/24 is directly connected, Serial0/1/0
L 10.1.4.1/32 is directly connected, Serial0/1/0
C 10.1.5.0/24 is directly connected, FastEthernet0/0
L 10.1.5.1/32 is directly connected, FastEthernet0/0
172.16.0.0/24 is subnetted, 1 subnets
S 172.16.10.0/24 [150/0] via 10.1.5.2
S 192.168.10.0/24 [150/0] via 10.1.2.2
S 192.168.20.0/24 [150/0] via 10.1.3.2
S 192.168.30.0/24 [150/0] via 10.1.4.2
S 192.168.40.0/24 [150/0] via 10.1.4.2
Corp routing table after RIP set on R1:
Gateway of last resort is not set
10.0.0.0/8 is variably subnetted, 10 subnets, 2 masks
C 10.1.1.0/24 is directly connected, Vlan1
L 10.1.1.1/32 is directly connected, Vlan1
C 10.1.2.0/24 is directly connected, Serial0/0/0
L 10.1.2.1/32 is directly connected, Serial0/0/0
C 10.1.3.0/24 is directly connected, Serial0/0/1
L 10.1.3.1/32 is directly connected, Serial0/0/1
C 10.1.4.0/24 is directly connected, Serial0/1/0
L 10.1.4.1/32 is directly connected, Serial0/1/0
C 10.1.5.0/24 is directly connected, FastEthernet0/0
L 10.1.5.1/32 is directly connected, FastEthernet0/0
nothing changed so far
172.16.0.0/24 is subnetted, 1 subnets
S 172.16.10.0/24 [150/0] via 10.1.5.2
no change
R 192.168.10.0/24 [120/1] via 10.1.2.2, 00:00:08, Serial0/0/0
[120/1] via 10.1.3.2, 00:00:08, Serial0/0/1
RIP overrides static- 2 paths available now
R 192.168.20.0/24 [120/1] via 10.1.2.2, 00:00:08, Serial0/0/0
[120/1] via 10.1.3.2, 00:00:08, Serial0/0/1
RIP overrides static- 2 paths available now
S 192.168.30.0/24 [150/0] via 10.1.4.2
no change
S 192.168.40.0/24 [150/0] via 10.1.4.2
no change
"Hi Corp- I'm R1 and I have zero networks
that fall inside 10.0.0.0, however I do have some networks that fall within
192.168.20.0 and 192.168.10.0
and you can reach them through me(R1) if you ingress at .1.2.2 or .1.3.2"
ok, we have the concept down. Time to proceed and set up RIP on R2............
R2(config)#
router rip
R2(config-router)#
network 10.0.0.0
R2(config-router)#
network 192.168.30.0
R2(config-router)#
network 192.168.40.0
R2 before RIP enabled
R2#
show ip route
10.0.0.0/24 is subnetted, 5 subnets
S 10.1.1.0 [150/0] via 10.1.4.1
S 10.1.2.0 [150/0] via 10.1.4.1
S 10.1.3.0 [150/0] via 10.1.4.1
C 10.1.4.0 is directly connected, Serial0/0/0
S 10.1.5.0 [150/0] via 10.1.4.1
172.16.0.0/24 is subnetted, 1 subnets
S 172.16.10.0 [150/0] via 10.1.4.1
S 192.168.10.0/24 [150/0] via 10.1.4.1
S 192.168.20.0/24 [150/0] via 10.1.4.1
C 192.168.30.0/24 is directly connected, FastEthernet0/0
C 192.168.40.0/24 is directly connected, FastEthernet0/1
R2 after RIP added
R2#
show ip route
10.0.0.0/24 is subnetted, 5 subnets
R 10.1.1.0 [120/1] via 10.1.4.1, 00:00:24, Serial0/0/0
from corp
R 10.1.2.0 [120/1] via 10.1.4.1, 00:00:24, Serial0/0/0
from corp
R 10.1.3.0 [120/1] via 10.1.4.1, 00:00:24, Serial0/0/0
from corp
C 10.1.4.0 is directly connected, Serial0/0/0
R 10.1.5.0 [120/1] via 10.1.4.1, 00:00:24, Serial0/0/0
from corp
172.16.0.0/24 is subnetted, 1 subnets
S 172.16.10.0 [150/0] via 10.1.4.1
R 192.168.10.0/24 [120/2] via 10.1.4.1, 00:00:24, Serial0/0/0
from R1 via corp
R 192.168.20.0/24 [120/2] via 10.1.4.1, 00:00:24, Serial0/0/0
from R1 via corp
C 192.168.30.0/24 is directly connected, FastEthernet0/0
C 192.168.40.0/24 is directly connected, FastEthernet0/1
now lets compare the Corp and R1 routing tables- before RIP was set on R2 and after
Corp before R2 RIP
Corp#
show ip route
10.0.0.0/8 is variably subnetted, 10 subnets, 2 masks
C 10.1.1.0/24 is directly connected, Vlan1
L 10.1.1.1/32 is directly connected, Vlan1
C 10.1.2.0/24 is directly connected, Serial0/0/0
L 10.1.2.1/32 is directly connected, Serial0/0/0
C 10.1.3.0/24 is directly connected, Serial0/0/1
L 10.1.3.1/32 is directly connected, Serial0/0/1
C 10.1.4.0/24 is directly connected, Serial0/1/0
L 10.1.4.1/32 is directly connected, Serial0/1/0
C 10.1.5.0/24 is directly connected, FastEthernet0/0
L 10.1.5.1/32 is directly connected, FastEthernet0/0
172.16.0.0/24 is subnetted, 1 subnets
S 172.16.10.0/24 [150/0] via 10.1.5.2
R 192.168.10.0/24 [120/1] via 10.1.2.2, 00:00:02, Serial0/0/0
[120/1] via 10.1.3.2, 00:00:02, Serial0/0/1
R 192.168.20.0/24 [120/1] via 10.1.2.2, 00:00:02, Serial0/0/0
[120/1] via 10.1.3.2, 00:00:02, Serial0/0/1
from R1
S 192.168.30.0/24 [150/0] via 10.1.4.2
S 192.168.40.0/24 [150/0] via 10.1.4.2
Corp after R2 RIP
Corp#
show ip route
10.0.0.0/8 is variably subnetted, 10 subnets, 2 masks
C 10.1.1.0/24 is directly connected, Vlan1
L 10.1.1.1/32 is directly connected, Vlan1
C 10.1.2.0/24 is directly connected, Serial0/0/0
L 10.1.2.1/32 is directly connected, Serial0/0/0
C 10.1.3.0/24 is directly connected, Serial0/0/1
L 10.1.3.1/32 is directly connected, Serial0/0/1
C 10.1.4.0/24 is directly connected, Serial0/1/0
L 10.1.4.1/32 is directly connected, Serial0/1/0
C 10.1.5.0/24 is directly connected, FastEthernet0/0
L 10.1.5.1/32 is directly connected, FastEthernet0/0
172.16.0.0/24 is subnetted, 1 subnets
S 172.16.10.0/24 [150/0] via 10.1.5.2
R 192.168.10.0/24 [120/1] via 10.1.2.2, 00:00:19, Serial0/0/0
[120/1] via 10.1.3.2, 00:00:19, Serial0/0/1
R 192.168.20.0/24 [120/1] via 10.1.2.2, 00:00:19, Serial0/0/0
[120/1] via 10.1.3.2, 00:00:19, Serial0/0/1
from R1
R 192.168.30.0/24 [120/1] via 10.1.4.2, 00:00:15, Serial0/1/0
R 192.168.40.0/24 [120/1] via 10.1.4.2, 00:00:15, Serial0/1/0
from R2
RIP on R2 is advertising .30.0 and .40.0 to Corp
R1 before R2 RIP
R1#
show ip route
10.0.0.0/24 is subnetted, 5 subnets
R 10.1.1.0 [120/1] via 10.1.2.1, 00:00:05, Serial0/0/0
[120/1] via 10.1.3.1, 00:00:05, Serial0/0/1
from Corp
C 10.1.2.0 is directly connected, Serial0/0/0
C 10.1.3.0 is directly connected, Serial0/0/1
R 10.1.4.0 [120/1] via 10.1.2.1, 00:00:05, Serial0/0/0
[120/1] via 10.1.3.1, 00:00:05, Serial0/0/1
R 10.1.5.0 [120/1] via 10.1.2.1, 00:00:05, Serial0/0/0
[120/1] via 10.1.3.1, 00:00:05, Serial0/0/1
from Corp
172.16.0.0/24 is subnetted, 1 subnets
S 172.16.10.0 [150/0] via 10.1.3.1
C 192.168.10.0/24 is directly connected, FastEthernet0/0
C 192.168.20.0/24 is directly connected, FastEthernet0/1
S 192.168.30.0/24 [150/0] via 10.1.3.1
S 192.168.40.0/24 [150/0] via 10.1.2.1
R1 after R2 RIP
R1#
show ip route
10.0.0.0/24 is subnetted, 5 subnets
R 10.1.1.0 [120/1] via 10.1.2.1, 00:00:06, Serial0/0/0
[120/1] via 10.1.3.1, 00:00:06, Serial0/0/1
from Corp
C 10.1.2.0 is directly connected, Serial0/0/0
C 10.1.3.0 is directly connected, Serial0/0/1
R 10.1.4.0 [120/1] via 10.1.2.1, 00:00:06, Serial0/0/0
[120/1] via 10.1.3.1, 00:00:06, Serial0/0/1
R 10.1.5.0 [120/1] via 10.1.2.1, 00:00:06, Serial0/0/0
[120/1] via 10.1.3.1, 00:00:06, Serial0/0/1
from Corp
172.16.0.0/24 is subnetted, 1 subnets
S 172.16.10.0 [150/0] via 10.1.3.1
C 192.168.10.0/24 is directly connected, FastEthernet0/0
C 192.168.20.0/24 is directly connected, FastEthernet0/1
R 192.168.30.0/24 [120/2] via 10.1.3.1, 00:00:06, Serial0/0/1
[120/2] via 10.1.2.1, 00:00:06, Serial0/0/0
R 192.168.40.0/24 [120/2] via 10.1.2.1, 00:00:06, Serial0/0/0
[120/2] via 10.1.3.1, 00:00:06, Serial0/0/1
from R2 via Corp
Now to set RIP on R3
R3(config)#
router rip
R3(config-router)#
network 10.0.0.0
R3(config-router)#
network 172.16.0.0
note that R3 is our only router with "gateway of last resort" set because we set a default route instead of static routes
As a result, we only see directly connected routes listed, along with a single "S*" for the default gateway
R3 before RIP
R3#
show ip route
Gateway of last resort is 10.1.5.1 to network 0.0.0.0
10.0.0.0/8 is variably subnetted, 2 subnets, 2 masks
C 10.1.5.0/24 is directly connected, FastEthernet0/0
L 10.1.5.2/32 is directly connected, FastEthernet0/0
172.16.0.0/16 is variably subnetted, 2 subnets, 2 masks
C 172.16.10.0/24 is directly connected, Dot11Radio0/0/0
L 172.16.10.1/32 is directly connected, Dot11Radio0/0/0
S* 0.0.0.0/0 [1/0] via 10.1.5.1
R3 after RIP
R3#
show ip route
Gateway of last resort is 10.1.5.1 to network 0.0.0.0
-------------------------------------------------------------
10.0.0.0/8 is variably subnetted, 6 subnets, 2 masks
R 10.1.1.0/24 [120/1] via 10.1.5.1, 00:00:21, FastEthernet0/0
R 10.1.2.0/24 [120/1] via 10.1.5.1, 00:00:21, FastEthernet0/0
R 10.1.3.0/24 [120/1] via 10.1.5.1, 00:00:21, FastEthernet0/0
R 10.1.4.0/24 [120/1] via 10.1.5.1, 00:00:21, FastEthernet0/0
from Corp
C 10.1.5.0/24 is directly connected, FastEthernet0/0
L 10.1.5.2/32 is directly connected, FastEthernet0/0
-------------------------------------------------------------
172.16.0.0/16 is variably subnetted, 2 subnets, 2 masks
C 172.16.10.0/24 is directly connected, Dot11Radio0/0/0
L 172.16.10.1/32 is directly connected, Dot11Radio0/0/0
R 192.168.10.0/24 [120/2] via 10.1.5.1, 00:00:21, FastEthernet0/0
R 192.168.20.0/24 [120/2] via 10.1.5.1, 00:00:21, FastEthernet0/0
From R1 via Corp
R 192.168.30.0/24 [120/2] via 10.1.5.1, 00:00:21, FastEthernet0/0
R 192.168.40.0/24 [120/2] via 10.1.5.1, 00:00:21, FastEthernet0/0
From R2 via Corp
S* 0.0.0.0/0 [1/0] via 10.1.5.1
Corp before R3 RIP
Corp#
show ip route
10.0.0.0/8 is variably subnetted, 10 subnets, 2 masks
C 10.1.1.0/24 is directly connected, Vlan1
L 10.1.1.1/32 is directly connected, Vlan1
C 10.1.2.0/24 is directly connected, Serial0/0/0
L 10.1.2.1/32 is directly connected, Serial0/0/0
C 10.1.3.0/24 is directly connected, Serial0/0/1
L 10.1.3.1/32 is directly connected, Serial0/0/1
C 10.1.4.0/24 is directly connected, Serial0/1/0
L 10.1.4.1/32 is directly connected, Serial0/1/0
C 10.1.5.0/24 is directly connected, FastEthernet0/0
L 10.1.5.1/32 is directly connected, FastEthernet0/0
172.16.0.0/24 is subnetted, 1 subnets
S 172.16.10.0/24 [150/0] via 10.1.5.2
R 192.168.10.0/24 [120/1] via 10.1.2.2, 00:00:26, Serial0/0/0
[120/1] via 10.1.3.2, 00:00:26, Serial0/0/1
R 192.168.20.0/24 [120/1] via 10.1.2.2, 00:00:26, Serial0/0/0
[120/1] via 10.1.3.2, 00:00:26, Serial0/0/1
from R1 via corp
R 192.168.30.0/24 [120/1] via 10.1.4.2, 00:00:21, Serial0/1/0
R 192.168.40.0/24 [120/1] via 10.1.4.2, 00:00:21, Serial0/1/0
from R2 via corp
Corp after R3 RIP
Corp#
show ip route
10.0.0.0/8 is variably subnetted, 10 subnets, 2 masks
C 10.1.1.0/24 is directly connected, Vlan1
L 10.1.1.1/32 is directly connected, Vlan1
C 10.1.2.0/24 is directly connected, Serial0/0/0
L 10.1.2.1/32 is directly connected, Serial0/0/0
C 10.1.3.0/24 is directly connected, Serial0/0/1
L 10.1.3.1/32 is directly connected, Serial0/0/1
C 10.1.4.0/24 is directly connected, Serial0/1/0
L 10.1.4.1/32 is directly connected, Serial0/1/0
C 10.1.5.0/24 is directly connected, FastEthernet0/0
L 10.1.5.1/32 is directly connected, FastEthernet0/0
172.16.0.0/16 is variably subnetted, 2 subnets, 2 masks
R 172.16.0.0/16 [120/1] via 10.1.5.2, 00:00:13, FastEthernet0/0
S 172.16.10.0/24 [150/0] via 10.1.5.2
from R3
R 192.168.10.0/24 [120/1] via 10.1.3.2, 00:00:13, Serial0/0/1
[120/1] via 10.1.2.2, 00:00:13, Serial0/0/0
R 192.168.20.0/24 [120/1] via 10.1.3.2, 00:00:13, Serial0/0/1
[120/1] via 10.1.2.2, 00:00:13, Serial0/0/0
from R1 via corp
R 192.168.30.0/24 [120/1] via 10.1.4.2, 00:00:24, Serial0/1/0
R 192.168.40.0/24 [120/1] via 10.1.4.2, 00:00:24, Serial0/1/0
from R2 via corp
R2 before R3 RIP
R2#
show ip route
10.0.0.0/24 is subnetted, 5 subnets
R 10.1.1.0 [120/1] via 10.1.4.1, 00:00:15, Serial0/0/0
R 10.1.2.0 [120/1] via 10.1.4.1, 00:00:15, Serial0/0/0
R 10.1.3.0 [120/1] via 10.1.4.1, 00:00:15, Serial0/0/0
from Corp
C 10.1.4.0 is directly connected, Serial0/0/0
R 10.1.5.0 [120/1] via 10.1.4.1, 00:00:15, Serial0/0/0
from Corp
172.16.0.0/24 is subnetted, 1 subnets
S 172.16.10.0 [150/0] via 10.1.4.1
R 192.168.10.0/24 [120/2] via 10.1.4.1, 00:00:15, Serial0/0/0
R 192.168.20.0/24 [120/2] via 10.1.4.1, 00:00:15, Serial0/0/0
from R1 via Corp
C 192.168.30.0/24 is directly connected, FastEthernet0/0
C 192.168.40.0/24 is directly connected, FastEthernet0/1
R2 after R3 RIP
R2#
show ip route
10.0.0.0/24 is subnetted, 5 subnets
R 10.1.1.0 [120/1] via 10.1.4.1, 00:00:20, Serial0/0/0
R 10.1.2.0 [120/1] via 10.1.4.1, 00:00:20, Serial0/0/0
R 10.1.3.0 [120/1] via 10.1.4.1, 00:00:20, Serial0/0/0
from Corp
C 10.1.4.0 is directly connected, Serial0/0/0
R 10.1.5.0 [120/1] via 10.1.4.1, 00:00:20, Serial0/0/0
from Corp
172.16.0.0/16 is variably subnetted, 2 subnets, 2 masks
R 172.16.0.0/16 [120/2] via 10.1.4.1, 00:00:20, Serial0/0/0
S 172.16.10.0/24 [150/0] via 10.1.4.1
from R3 via Corp
R 192.168.10.0/24 [120/2] via 10.1.4.1, 00:00:20, Serial0/0/0
R 192.168.20.0/24 [120/2] via 10.1.4.1, 00:00:20, Serial0/0/0
from R1 via Corp
C 192.168.30.0/24 is directly connected, FastEthernet0/0
C 192.168.40.0/24 is directly connected, FastEthernet0/1
R1 before R3 RIP
R1#
show ip route
10.0.0.0/24 is subnetted, 5 subnets
R 10.1.1.0 [120/1] via 10.1.2.1, 00:00:04, Serial0/0/0
[120/1] via 10.1.3.1, 00:00:04, Serial0/0/1
C 10.1.2.0 is directly connected, Serial0/0/0
C 10.1.3.0 is directly connected, Serial0/0/1
R 10.1.4.0 [120/1] via 10.1.2.1, 00:00:04, Serial0/0/0
[120/1] via 10.1.3.1, 00:00:04, Serial0/0/1
R 10.1.5.0 [120/1] via 10.1.2.1, 00:00:04, Serial0/0/0
[120/1] via 10.1.3.1, 00:00:04, Serial0/0/1
from Corp
172.16.0.0/24 is subnetted, 1 subnets
S 172.16.10.0 [150/0] via 10.1.3.1
C 192.168.10.0/24 is directly connected, FastEthernet0/0
C 192.168.20.0/24 is directly connected, FastEthernet0/1
R 192.168.30.0/24 [120/2] via 10.1.2.1, 00:00:04, Serial0/0/0
[120/2] via 10.1.3.1, 00:00:04, Serial0/0/1
R 192.168.40.0/24 [120/2] via 10.1.2.1, 00:00:04, Serial0/0/0
[120/2] via 10.1.3.1, 00:00:04, Serial0/0/1
from R2 via Corp
R1 after R3 RIP
R1#
show ip route
10.0.0.0/24 is subnetted, 5 subnets
R 10.1.1.0 [120/1] via 10.1.3.1, 00:00:03, Serial0/0/1
[120/1] via 10.1.2.1, 00:00:03, Serial0/0/0
C 10.1.2.0 is directly connected, Serial0/0/0
C 10.1.3.0 is directly connected, Serial0/0/1
R 10.1.4.0 [120/1] via 10.1.3.1, 00:00:03, Serial0/0/1
[120/1] via 10.1.2.1, 00:00:03, Serial0/0/0
R 10.1.5.0 [120/1] via 10.1.3.1, 00:00:03, Serial0/0/1
[120/1] via 10.1.2.1, 00:00:03, Serial0/0/0
from Corp
172.16.0.0/16 is variably subnetted, 2 subnets, 2 masks
R 172.16.0.0/16 [120/2] via 10.1.3.1, 00:00:03, Serial0/0/1
[120/2] via 10.1.2.1, 00:00:03, Serial0/0/0
S 172.16.10.0/24 [150/0] via 10.1.3.1
from R3 via Corp
C 192.168.10.0/24 is directly connected, FastEthernet0/0
C 192.168.20.0/24 is directly connected, FastEthernet0/1
R 192.168.30.0/24 [120/2] via 10.1.3.1, 00:00:03, Serial0/0/1
[120/2] via 10.1.2.1, 00:00:03, Serial0/0/0
R 192.168.40.0/24 [120/2] via 10.1.3.1, 00:00:03, Serial0/0/1
[120/2] via 10.1.2.1, 00:00:03, Serial0/0/0
from R2 via Corp
Verifying Configurations
in addition to
show ip route
we can also use
show ip protocols
and
debug rip ip
Corp#
show ip protocols
Routing Protocol is "rip"
Sending updates every 30 seconds, next due in 11 seconds
Invalid after 180 seconds, hold down 180, flushed after 240
Outgoing update filter list for all interfaces is not set
Incoming update filter list for all interfaces is not set
Redistributing: rip
Default version control: send version 1, receive any version
Interface Send Recv Triggered RIP Key-chain
Vlan1 1 2 1
FastEthernet0/0 1 2 1
Serial0/0/1 1 2 1
Serial0/1/0 1 2 1
Serial0/0/0 1 2 1
Automatic network summarization is in effect
Maximum path: 4
Routing for Networks:
10.0.0.0
Passive Interface(s):
Routing Information Sources:
Gateway Distance Last Update
10.1.5.2 120 00:00:00
10.1.3.2 120 00:00:10
10.1.2.2 120 00:00:10
10.1.4.2 120 00:00:20
Distance: (default is 120)
R3#
debug ip rip
R3#RIP: received v1 update from 10.1.5.1 on FastEthernet0/0
10.1.1.0 in 1 hops
10.1.2.0 in 1 hops
10.1.3.0 in 1 hops
10.1.4.0 in 1 hops
192.168.10.0 in 2 hops
192.168.20.0 in 2 hops
192.168.30.0 in 2 hops
192.168.40.0 in 2 hops
R3#RIP: sending v1 update to 255.255.255.255 via Dot11Radio0/0/0 (172.16.10.1)
RIP: build update entries
network 10.0.0.0 metric 1
network 192.168.10.0 metric 3
network 192.168.20.0 metric 3
network 192.168.30.0 metric 3
network 192.168.40.0 metric 3
RIP: sending v1 update to 255.255.255.255 via FastEthernet0/0 (10.1.5.2)
RIP: build update entries
network 172.16.0.0 metric 1
output loops until manually disabled..............
R3#
undebug all
All possible debugging has been turned off
Note that due to the Split Horizon rule, R3 is not sending all of it's known RIP data to Corp.
It is sending all known RIP data out of the wifi interface (even there though there's no router that way),
but it is ONLY sending data about the wifi network back to Corp; data that Corp doesnt already have
Now lets look at some examples with sample routers..
I got hung up on these two examples because I found the
wording to be a bit confusing. Also there was subnetting involved that I was able to figure out, but threw me at first
First source of confusion- we have two seperate examples, and I was mixing them up.
The examples are:
Use the debug ip rip command to both:
discover a problem
and figure out how RIP was configured on a router from a different sample network
The conclusion regarding 'figuring out how RIP is configured' on this router, is that RIP networks are set as 10.0.0.0 and 172.16.0.0.
We determined that we are not the 'first source' of info on the 192.168.1.0 nertwork, since it is a metric of 2. We are sending out RIP data on that network,
but that RIP data is made availbale to us via another router.
I also got tripped up on the fact that RA is sending out S0/0 which corresponds 10.0.8.1,
and then receiving on the same interface S0/0 from an ip address of 10.0.15.0 on the other side of the link
I was able to determine that these two address are actually on the same subnet. My initial assumption was that the network address for the link is 10.0.0.0.
The problem doesn't give the subnet mask- I guessed it as /20 by using a 16 block since we can see that the third octet seems to move in 8's
if the network starts at 10.0.0.0 and we use /20 with 16 block, we would indeed have a last host address of 10.0.15.254, so 10.0.15.2 would be a valid host.
So there was a twist to this problem which needed subnetting to solve. It wasnt particulary releveant to the subject of RIP, but I was curious why the address on
the other side of that link looked so strange.
The problem also points out that we can determine there are 'at least' two routers participating in RIP here since we are sending RIP data out two interfaces but
only receiving RIP data on one interface. I'm unclear on why its worded this way; we know we are a RIP router- the fact that we are receiving data on one interface
would suggest there is 'at least one more' RIP router out there.
that's it for this example. Back to the original statement-
Use the debug ip rip command to both discover a problem and figure out
how RIP was configured on a router from a different sample network
We just 'figured out how RIP was configured on a router'.. The second example is regarding 'discovering a problem', although it is mentioned first.
The second example will use debug ip rip and show ip route to find a problem with the network
it looks like RIP data for 172.16.20.0 was received on S0/0, and then that interface was bumped out of the routing table entry for that network in favor of a static route.
ok, moving on now to RIP V2
RIP V2
enable it on all four routers
Corp(config)
router rip
Corp(config-router)
version 2
R1(config)
router rip
R1(config-router)
version 2
R2(config)
router rip
R2(config-router)
version 2
R3(config)
router rip
R3(config-router)
version 2
We'll use R1 to compare RIPv1 and RIPv2
RIPv1
R1(config)
debug ip rip
R1#RIP: sending v1 update to 255.255.255.255 via FastEthernet0/0 (192.168.10.1)
RIP: build update entries
network 10.0.0.0 metric 1
network 172.16.0.0 metric 3
network 192.168.20.0 metric 1
network 192.168.30.0 metric 3
network 192.168.40.0 metric 3
RIP: sending v1 update to 255.255.255.255 via FastEthernet0/1 (192.168.20.1)
RIP: build update entries
network 10.0.0.0 metric 1
network 172.16.0.0 metric 3
network 192.168.10.0 metric 1
network 192.168.30.0 metric 3
network 192.168.40.0 metric 3
RIP: sending v1 update to 255.255.255.255 via Serial0/0/0 (10.1.2.2)
RIP: build update entries
network 10.1.3.0 metric 1
network 192.168.10.0 metric 1
network 192.168.20.0 metric 1
RIP: sending v1 update to 255.255.255.255 via Serial0/0/1 (10.1.3.2)
RIP: build update entries
network 10.1.2.0 metric 1
network 192.168.10.0 metric 1
network 192.168.20.0 metric 1
RIPv2
R1(config)
debug ip rip
R1#RIP: sending v2 update to 224.0.0.9 via FastEthernet0/0 (192.168.10.1)
RIP: build update entries
10.0.0.0/8 via 0.0.0.0, metric 1, tag 0
172.16.0.0/16 via 0.0.0.0, metric 3, tag 0
192.168.20.0/24 via 0.0.0.0, metric 1, tag 0
192.168.30.0/24 via 0.0.0.0, metric 3, tag 0
192.168.40.0/24 via 0.0.0.0, metric 3, tag 0
RIP: sending v2 update to 224.0.0.9 via FastEthernet0/1 (192.168.20.1)
RIP: build update entries
10.0.0.0/8 via 0.0.0.0, metric 1, tag 0
172.16.0.0/16 via 0.0.0.0, metric 3, tag 0
192.168.10.0/24 via 0.0.0.0, metric 1, tag 0
192.168.30.0/24 via 0.0.0.0, metric 3, tag 0
192.168.40.0/24 via 0.0.0.0, metric 3, tag 0
RIP: sending v2 update to 224.0.0.9 via Serial0/0/0 (10.1.2.2)
RIP: build update entries
10.1.3.0/24 via 0.0.0.0, metric 1, tag 0
192.168.10.0/24 via 0.0.0.0, metric 1, tag 0
192.168.20.0/24 via 0.0.0.0, metric 1, tag 0
RIP: sending v2 update to 224.0.0.9 via Serial0/0/1 (10.1.3.2)
RIP: build update entries
10.1.2.0/24 via 0.0.0.0, metric 1, tag 0
192.168.10.0/24 via 0.0.0.0, metric 1, tag 0
192.168.20.0/24 via 0.0.0.0, metric 1, tag 0
R1(config)
show ip protocols
Routing Protocol is "rip"
Sending updates every 30 seconds, next due in 13 seconds
Invalid after 180 seconds, hold down 180, flushed after 240
Outgoing update filter list for all interfaces is not set
Incoming update filter list for all interfaces is not set
Redistributing: rip
Default version control: send version 2, receive 2
Interface Send Recv Triggered RIP Key-chain
FastEthernet0/0 2 2
FastEthernet0/1 2 2
Serial0/0/0 2 2
Serial0/0/1 2 2
Automatic network summarization is in effect
Maximum path: 4
Routing for Networks:
10.0.0.0
192.168.10.0
192.168.20.0
Passive Interface(s):
Routing Information Sources:
Gateway Distance Last Update
10.1.3.1 120 00:00:21
10.1.2.1 120 00:00:21
Distance: (default is 120)
final task of this chapter
Enable a default route out to the internet , and advertise via RIP
R3(config)#
interface s0/1/0 (this is only for example, so I am not adding a serial card to R3)
R3(config-if)#
ip addr 172.16.10.5 255.255.255.252
R3(config-if)#
exit
R3(config)#
ip route 0.0.0.0 0.0.0.0 s0/0
R3(config)#
ip default-network 172.16.0.0 tells other routers via RIP that default WAN route is through R3
Chapter 8 Exam Essentials IP Routing
1. Describe the Basic IP routing process
frame changes at each hop, but packet doesnt change EXCEPT that the TTL field in the IP header decrements
2. List the information required by a router to successfully route packets
destination IP address, location of other routers, possible routers to all remote networks,
the best route to each network, how to maintain and maintain routing info
3. Describe how MAC addresses are used during the routing process
a MAC will never pass a router interface. MACs will change between router interfaces
4. View and interpret the routing table of a router
use show ip route to see the table
a "C" indicates directly connected, an "R" indicates RIP provided the route info, "S" means static
5. differentiate the three types of routing
static- manually configured
dynamic- routers automatically share info via protocol
default- a special route is configured for all traffic without a more specific destination network found in the table
6. Compare and contrast static and dynamic routing
static routing creates no routing update traffic which means less overhead on the routers and links- but it must be
configured manually and can't react if links are lost.
dynamic routing creates update traffic, but it can react to outages and choose the best route when multiple routes exist to the same network
7. Configure static routes at the CLI
route [dest network] [mask] [next hop address OR exit interface] [admin distance] [permanent]
Ex:
Corp(config)#
ip route 192.168.10.0 255.255.255.0 10.1.2.2 150
8. Create a default route
ip route 0.0.0.0 0.0.0.0 [ip address OR exit interface]
Ex:
R3(config)#
ip route 0.0.0.0 0.0.0.0 10.1.5.1 (ingress at Corp router- use if R3 cant identify route)
9. Understand administrative distance and its role in the selection of the best route
an integer from 0 (most trusted) to 255 (no traffic will pass via this route).
All routing protocols are assigned an AD but it can be changed at the CLI
10. Differentiate distance-vector, link-state, and hybrid routing protocols
distance vector- based on hop count (RIP)
link-state- multiple factors such as bandwidth and delay
hybrid- uses both
11. List mechanisms used to prevent routing loops in the network
max hop count, split horizon, route poisoning, holddown counters
12. Describe the counts used the operation of RIP
route update timer- (30) interval between routing updates
route invalid timer- (180, update x 3) before a route is determined invalid
holddown timer-(180) time info is supressed when a link is lost
route flush timer- (240) seconds before invalid and removal
13. Configure RIP routing
router rip
network x.x.x.x
the network(s) you want to advertise from your router. It only works if the other router has RIP enabled.
By enabling RIP, you are able to RECEIVE RIP data from other RIP routers.
by specifying a network, you are SENDING RIP data on that network
14. Identify commands used to verify RIP routing
show ip route will provide contents of the routing table with codes (R, C, S)
debug ip rip will show RIP updates being sent and received
15. Describe the differences between RIPv1 and RIPv2
RIPv1 sends a broadcast (255.255.255.255) every 30 seconds and has an AD of 120.
RIPv1 is classful only, does not send any mask info. No authentication between routers.
RIPv2 sends multicasts (224.0.0.9) every 30 seconds and sends mask info, which allows it to support classless networking, RIPv2 also supports
autentication between routers.
Chapter 8 Written Lab 8.0
1. At the appropriate prompt, create a static route to network 172.16.10.0/24 with a next-hop
gateway of 172.16.20.1 and an administrative distance of 150.
Router(config)#
ip route 172.16.10.0 255.255.255.0 172.16.20.1 150
2. When a PC sends a packet to another PC in a remote network, what destination IP address and MAC address will
be in the frame that it sends to it's default gateway?
the gateway interface MAC and the remote PC's IP
3. At the appropriate prompt, create a default route to 172.16.40.1
Router(config)#
ip route 0.0.0.0 0.0.0.0 172.16.40.1
"to" is the wrong word.. we are going TO any route VIA 172.16.40.1
4. If you are using default routing in a classless environment, what command must also be used?
Router(config)#
ip classless
5. On which type of network is a default route most beneficial?
stub
6. At the appropriate prompt, display the routing table on your router
Router#
show ip route
7. When creating a static or default route, you dont have to use the next-hop ip address;
you can instead use the ____________
exit interface
8. True/False: To reach a destination host, you must know the MAC address of the remote host
false, you need the MAC of your router
9. True/False: To reach a destination host, you must know the IP address of the remote host
true
10. At the appropriate prompt, execute the command required on a DCE serial interface that is not required
on a DTE serial interface
Router(config-if)#
clock rate X
11. At the appropriate prompt, enable RIP routing on the interface with the IP address 10.0.0.1/24
Router(config)#
router rip
Router(config-router)#
network 10.0.0.0
RIPv1 is CLASSFUL only... use the classful mask based on the first octet given
12. At the appropriate prompt, prevent a router from propagating IP information out serial 1
Router(config)#
router rip
Router(config-router)#
passive-interface S0/1
can receive RIP data but will not send
13. What routing loop prevention mechanism sends out a maximum hop count as soon as a link fails?
route poisoning
14. What routing loop prevention mechanism suppresses the resending of routing information to an interface
through which it was received?
split horizon
15. At the appropriate prompt display RIP routing updates as they are sent and received on the router
to the console session
Router#
debug ip rip
to turn it off:
Router#
undebug all
Chapter 8 Hands-on Labs
For these labs we will need a network with three routers.
Lab 8.1 Creating Static routes
first set the interfaces, then program the static routes
LabA(config)#
int s0/0/0
LabA(config-if)#
ip addr 172.16.20.1
LabA(config-if)#
int f0/0
LabA(config-if)#
ip addr 172.16.10.1
-----------------------------------------------------------------
LabA(config)#
ip route 172.16.30.0 255.255.255.0 172.16.20.2
LabA(config)#
ip route 172.16.40.0 255.255.255.0 172.16.20.2
LabB(config)#
int s0/0/0
LabB(config-if)#
ip addr 172.16.20.2
LabB(config-if)#
int s0/0/1
LabB(config-if)#
ip addr 172.16.30.1
-----------------------------------------------------------------
LabB(config)#
ip route 172.16.10.0 255.255.255.0 172.16.20.1
LabB(config)#
ip route 172.16.40.0 255.255.255.0 172.16.30.2
LabC(config)#
int s0/0/0
LabC(config-if)#
ip addr 172.16.30.2
LabC(config-if)#
int f0/0
LabC(config-if)#
ip addr 172.16.40.1
-----------------------------------------------------------------
LabC(config)#
ip route 172.16.10.0 255.255.255.0 172.16.30.1
LabC(config)#
ip route 172.16.20.0 255.255.255.0 172.16.30.1
Lab 8.2 RIP Configuration
remove the static routes, enable and configure RIP with the classful network id that covers the routes you want to advertise
LabA(config)#
no ip route 172.16.30.0 255.255.255.0 172.16.20.2
LabA(config)#
no ip route 172.16.40.0 255.255.255.0 172.16.20.2
LabA(config)#
router rip
LabA(config-router)#
network 172.16.0.0
LabA(config-router)#
do show ip route
Gateway of last resort is not set
172.16.0.0/16 is variably subnetted, 5 subnets, 2 masks
C 172.16.10.0/24 is directly connected, FastEthernet0/0
L 172.16.10.1/32 is directly connected, FastEthernet0/0
C 172.16.20.0/24 is directly connected, Serial0/0/0
L 172.16.20.1/32 is directly connected, Serial0/0/0
R 172.16.30.0/24 [120/1] via 172.16.20.2, 00:00:07, Serial0/0/0
from Lab B
LabB(config)#
no ip route 172.16.10.0 255.255.255.0 172.16.20.1
LabB(config)#
no ip route 172.16.40.0 255.255.255.0 172.16.30.2
LabB(config)#
router rip
LabB(config-router)#
network 172.16.0.0
LabB(config-router)#
do show ip route
Gateway of last resort is not set
172.16.0.0/16 is variably subnetted, 5 subnets, 2 masks
R 172.16.10.0/24 [120/1] via 172.16.20.1, 00:00:13, Serial0/0/0
from LabA
C 172.16.20.0/24 is directly connected, Serial0/0/0
L 172.16.20.2/32 is directly connected, Serial0/0/0
C 172.16.30.0/24 is directly connected, Serial0/0/1
L 172.16.30.1/32 is directly connected, Serial0/0/1
LabC(config)#
no ip route 172.16.10.0 255.255.255.0 172.16.30.1
LabC(config)#
no ip route 172.16.20.0 255.255.255.0 172.16.30.1
LabC(config)#
router rip
LabC(config-router)#
network 172.16.0.0
LabC(config-router)#
do show ip route
Gateway of last resort is not set
172.16.0.0/16 is variably subnetted, 3 subnets, 2 masks
R 172.16.20.0/24 [120/1] via 172.16.30.1, 00:00:05, Serial0/0/0
from LabB
C 172.16.30.0/24 is directly connected, Serial0/0/0
L 172.16.30.2/32 is directly connected, Serial0/0/0
Chapter 8 Review Questions
1. The Acme company uses a router named Gateway to connect to its ISP. The address of the ISP router is 206.143.5.2.
Which three commands could be configured on the gateway router to allow internet access to the entire network?
Set a default route:
Gateway(config)#
ip route 0.0.0.0 0.0.0.0 206.143.5.2 next hop IP
Gateway(config)#
ip route 0.0.0.0 0.0.0.0 S/0 exit interface instead of next hop IP
Gateway(config)#
ip default-network 206.143.5.0 next hop IP
2. What command will prevent RIP routing updates from exiting an interface but will sill allow the interface to receive RIP updates?
Router(config-if)#
passive-interface
3. Which two statemnts are true about ip route 172.16.4.0 255.255.255.0 192.168.4.2?
the command establishes a static route
the default admin distance is used (since we didnt give an AD argument)
4. What two destination addresses will be used by HostA to send data to the HTTPS server as shown in the following network?
MAC of RouterA f0/0 interface
IP address of the server
5. Which two statements are true about this output?
RIP: received v1 update from 192.168.40.2 on S0/1
192.168.50.0 in 16 hops (inaccessible)
RIP: sending v1 update to 255.255.255.255 via F0/0 (192.168.30.1)
RIP: build update entries
network 192.168.20.0 metric 1
network 192.168.40.0 metric 1
network 192.168.50.0 metric 16
RIP: sending v1 update to 255.255.255.255 via S0/1 (192.168.40.1)
true:
there are at least two routers exchanging information
192.168.40.2 will be successful
FALSE
there are three interfaces on the router participating in this update
false because we only see two interfaces represented in the output: S0/1(twice) and F0/0
a ping to 192.168.50.1 will be successful
false because that route has a metric of 16; it's unreachable
6. Describe split horizon
will not advertise a route back the the same router it was learned from
7. Which would be true if HostA is trying to communicate to HostB and interface F0/0 of RouterC goes down, as shown in the graphic?
RouterC will send an ICMP 'destination unreachable type' message to inform HostA that HostB is unreachable
8. Which two statements are true regarding classless routing protocols?
VLSM is permitted
RIPv2 supports classless
9. Which two are true regarding distance-vector vs link-state?
Distance vector sends the whole routing table out all active interfaces(even if a router isnt on the other end)at periodic time intervals
Link-state sends updates containing the state of its own links to all routers in the inter-network
10. Which command display RIP routing updates?
debug ip rip
11. What does RIPv2 use to prvent routing loops?
split horizon stops an update from being send on the same interface it was received
holdown timers allow time for a network to become stable in the case of a flapping link
12. A network administrator views the output from the show ip route command. A network that is advertised
by both RIP and EIGRP appears in the routing table flagged an EIGRP route. Why is the RIP route to this network not used in this routing table?
EIGRP has a lower AD.
RIP=120
OSPP=110
IGRP=110
EIGRP=90
13. You type debug ip rip on your router console and see that 172.16.10.0 is being advertised to you with a metric of 16. What does this mean?
it is inaccessible. in RIP if you see a route advertised with a metric of 16, it's inaccessible
14. What metric does RIPv2 use to find the best path to the remote network?
distance aka hop count
15. The Corporate router receives an IP packet with a source IP address of 192.168.214.20 and a destination address of 192.168.22.3. Looking at the output from the Corp router,
what will the router do with this packet?
Corp# show ip route
[cut]
R 192.168.215.0 [120/2] via 192.168.20.2, Serail0/0
R 192.168.115.0 [120/1] via 192.168.20.0, Serial0/0
R 192.168.30.0 [120/1] via 192.168.20.2, Serial0/0
C 192.168.20.0 is directly connected, Serial0/0
C 192.168.214.0 is directly connected, FastEthernet0/0
Since there is no route to that network, the router will discard the packet and send an ICMP destination unreachable message out F0/0 back the the source network
16. If your routing table has a static, a RIP and an EIGRP route to the same network, which route will be used by default?
Static routes have an admin distance of 1 by default. Unless you change it, a static route will always be used over any other
dynamically learned route.
17. You have the following routing table. Which network will NOT be placed in the neighbor routing table?
R 192.168.30.0/24 [120/1] via 192.168.40.1, Serial 0
C 192.168.40.0/24 is directly connected, Serial 0
172.16.0.0/2 is subnetted, 1 subnets
C 172.16.30.0 is directly connected, Loopback0
R 192.168.20.0/24 [120/1] via 192.168.40.1, Serial 0
R 10.0.0.0/8 [120/15] via 192.168.40.1, Serial 0
C 192.168.50.0/24 is directly connected, Ethernet 0
10.0.0.0 cant be placed in neighboring routing table because it is at 15 hops. 16 hops is invalid in RIP
18. Two connected routers are configured only with RIP. What will be the result when a router receives a routing update that contains a
higher-cost path to a network already in it's routing table?
The router will ignore the update because it is higher cost. When a routing update is received, the router first checks the AD and always chooses
the route with the lowest AD.
19.Which is true about route poisoning?
The router sets the metric for a downed link to "infinity".
20. Which is true about RIPv2?
it has all the same timers as RIPv1
------------------------------------------------------------------------------
END CHAPTER 8
54 hours 1-28 thru 2-14-22
original total 143 hours
11.5 hours review 12-23,24,26-22
review total hours 32
book page 428/822
avg 20 min/page (reading and exercises/labs)
Chapter 9 EIGRP and OSPF
pages 427-502, start 2-14-22-M
What is EIGRP?
Note it's not officially on CCNA 200-301 but it is still important to learn
Enhanced IGRP is a classless, enchanced distance vector protocol that uses the concept of an autonomous system to describe
the set of contigous routers that run the same routing protocol and share routing information.
Features:
Support for IP and IPv6 via protocol-dependent modules (seperate routing tables)
Considered classless
Support for summaries and discontiguous networks
Eficient neighbor discovery
communication via RTP- Reliable Transport Protocol
best path selection via Diffusing Updae Algorithm DUAL
Cisco considers EIGRP a "distance-vector" routing protocol
or an "advanced distance-vector" protocol
or a "hybrid" protocol
Configuring EIGRP on our network
------------------------------------------------------------------------------------------------------------------------------------
Corp(config)#
router eigrp ?
<1-65535> Autonomous system number
Corp(config)#
router eigrp 10
R2(config-router)#
network 10.0.0.0
after eigrp on R1- links from Corp to R1 are up
%DUAL-5-NBRCHANGE: IP-EIGRP 10: Neighbor 10.1.3.2 (Serial0/0/1) is up: new adjacency
%DUAL-5-NBRCHANGE: IP-EIGRP 10: Neighbor 10.1.2.2 (Serial0/0/0) is up: new adjacency
after eigrp on R2- link from Corp to R2 is up
%DUAL-5-NBRCHANGE: IP-EIGRP 10: Neighbor 10.1.4.2 (Serial0/1/0) is up: new adjacency
after eigrp on R3- link from Corp to R3 is up
%DUAL-5-NBRCHANGE: IP-EIGRP 10: Neighbor 10.1.5.2 (FastEthernet0/0) is up: new adjacency
------------------------------------------------------------------------------------------------------------------------------------
R1(config)#
router eigrp 10
R1(config-router)#
network 10.0.0.0
after eigrp on R1- link from R1 to Corp is up
%DUAL-5-NBRCHANGE: IP-EIGRP 10: Neighbor 10.1.3.1 (Serial0/0/1) is up: new adjacency
%DUAL-5-NBRCHANGE: IP-EIGRP 10: Neighbor 10.1.2.1 (Serial0/0/0) is up: new adjacency
R1(config-router)#
network 192.168.10.0
R1(config-router)#
network 192.168.20.0
------------------------------------------------------------------------------------------------------------------------------------
R2(config)#
router eigrp 10
R2(config-router)#
network 10.0.0.0
after eigrp on R2- link from R2 to Corp is up
%DUAL-5-NBRCHANGE: IP-EIGRP 10: Neighbor 10.1.4.1 (Serial0/0/0) is up: new adjacency
R1(config-router)#
network 192.168.30.0
R1(config-router)#
network 192.168.40.0
------------------------------------------------------------------------------------------------------------------------------------
R3(config)#
router eigrp 10
R3(config-router)#
network 10.0.0.0
after eigrp on R3- link from R3 to Corp is up
%DUAL-5-NBRCHANGE: IP-EIGRP 10: Neighbor 10.1.5.1 (FastEthernet0/0) is up: new adjacency
R1(config-router)#
network 172.16.0.0
------------------------------------------------------------------------------------------------------------------------------------
Corp#
show ip route
Gateway of last resort is not set
Gateway of last resort is not set
10.0.0.0/8 is variably subnetted, 10 subnets, 2 masks
C 10.1.1.0/24 is directly connected, Vlan1
L 10.1.1.1/32 is directly connected, Vlan1
C 10.1.2.0/24 is directly connected, Serial0/0/0
L 10.1.2.1/32 is directly connected, Serial0/0/0
C 10.1.3.0/24 is directly connected, Serial0/0/1
L 10.1.3.1/32 is directly connected, Serial0/0/1
C 10.1.4.0/24 is directly connected, Serial0/1/0
L 10.1.4.1/32 is directly connected, Serial0/1/0
C 10.1.5.0/24 is directly connected, FastEthernet0/0
L 10.1.5.1/32 is directly connected, FastEthernet0/0
172.16.0.0/16 is variably subnetted, 2 subnets, 2 masks
R 172.16.0.0/16 [120/1] via 10.1.5.2, 00:00:17, FastEthernet0/0
D 172.16.10.0/24 [90/28160] via 10.1.5.2, 00:00:16, FastEthernet0/0
via R3
D 192.168.10.0/24 [90/2172416] via 10.1.2.2, 00:19:13, Serial0/0/0
[90/2172416] via 10.1.3.2, 00:19:13, Serial0/0/1
D 192.168.20.0/24 [90/2172416] via 10.1.3.2, 00:19:05, Serial0/0/1
[90/2172416] via 10.1.2.2, 00:19:05, Serial0/0/0
via R1
D 192.168.30.0/24 [90/2172416] via 10.1.4.2, 00:01:31, Serial0/1/0
D 192.168.40.0/24 [90/2172416] via 10.1.4.2, 00:01:08, Serial0/1/0
via R2
The "D" routes are for DUAL- Diffusing Update Algorithm, indicating they are EIGRP routes.
Note that we have RIP and EIGRP set currently
------------------------------------------------------------------------------------------------------------------------------------
R1#
show ip route
Gateway of last resort is not set
10.0.0.0/8 is variably subnetted, 6 subnets, 2 masks
D 10.0.0.0/8 is a summary, 00:25:28, Null0
D 10.1.1.0/24 [90/27769856] via 10.1.2.1, 00:31:33, Serial0/0/0
[90/27769856] via 10.1.3.1, 00:31:30, Serial0/0/1
via Corp
C 10.1.2.0/24 is directly connected, Serial0/0/0
C 10.1.3.0/24 is directly connected, Serial0/0/1
D 10.1.4.0/24 [90/2681856] via 10.1.2.1, 00:31:33, Serial0/0/0
[90/2681856] via 10.1.3.1, 00:31:30, Serial0/0/1
D 10.1.5.0/24 [90/2172416] via 10.1.2.1, 00:31:33, Serial0/0/0
[90/2172416] via 10.1.3.1, 00:31:30, Serial0/0/1
via Corp
172.16.0.0/16 is variably subnetted, 2 subnets, 2 masks
R 172.16.0.0/16 [120/2] via 10.1.2.1, 00:00:07, Serial0/0/0
[120/2] via 10.1.3.1, 00:00:07, Serial0/0/1
D 172.16.10.0/24 [90/2172416] via 10.1.2.1, 00:06:31, Serial0/0/0
[90/2172416] via 10.1.3.1, 00:06:31, Serial0/0/1
via Corp
C 192.168.10.0/24 is directly connected, FastEthernet0/0
C 192.168.20.0/24 is directly connected, FastEthernet0/1
D 192.168.30.0/24 [90/2684416] via 10.1.3.1, 00:07:46, Serial0/0/1
[90/2684416] via 10.1.2.1, 00:07:46, Serial0/0/0
D 192.168.40.0/24 [90/2684416] via 10.1.2.1, 00:07:23, Serial0/0/0
[90/2684416] via 10.1.3.1, 00:07:23, Serial0/0/1
via Corp
------------------------------------------------------------------------------------------------------------------------------------
R2#
show ip route
Gateway of last resort is not set
10.0.0.0/8 is variably subnetted, 6 subnets, 2 masks
D 10.0.0.0/8 is a summary, 00:13:09, Null0
D 10.1.1.0/24 [90/27769856] via 10.1.4.1, 00:36:53, Serial0/0/0
D 10.1.2.0/24 [90/2681856] via 10.1.4.1, 00:36:53, Serial0/0/0
D 10.1.3.0/24 [90/2681856] via 10.1.4.1, 00:36:53, Serial0/0/0
via Corp
C 10.1.4.0/24 is directly connected, Serial0/0/0
D 10.1.5.0/24 [90/2172416] via 10.1.4.1, 00:36:53, Serial0/0/0
via Corp
172.16.0.0/16 is variably subnetted, 2 subnets, 2 masks
R 172.16.0.0/16 [120/2] via 10.1.4.1, 00:00:23, Serial0/0/0
D 172.16.10.0/24 [90/2172416] via 10.1.4.1, 00:11:54, Serial0/0/0
via Corp
D 192.168.10.0/24 [90/2684416] via 10.1.4.1, 00:30:51, Serial0/0/0
D 192.168.20.0/24 [90/2684416] via 10.1.4.1, 00:30:43, Serial0/0/0
via Corp
C 192.168.30.0/24 is directly connected, FastEthernet0/0
C 192.168.40.0/24 is directly connected, FastEthernet0/1
------------------------------------------------------------------------------------------------------------------------------------
R3#
show ip route
Gateway of last resort is 10.1.5.1 to network 0.0.0.0
10.0.0.0/8 is variably subnetted, 6 subnets, 2 masks
D 10.1.1.0/24 [90/25628160] via 10.1.5.1, 00:37:20, FastEthernet0/0
D 10.1.2.0/24 [90/2172416] via 10.1.5.1, 00:37:15, FastEthernet0/0
D 10.1.3.0/24 [90/2172416] via 10.1.5.1, 00:37:20, FastEthernet0/0
D 10.1.4.0/24 [90/2172416] via 10.1.5.1, 00:37:20, FastEthernet0/0
via Corp
C 10.1.5.0/24 is directly connected, FastEthernet0/0
L 10.1.5.2/32 is directly connected, FastEthernet0/0
172.16.0.0/16 is variably subnetted, 2 subnets, 2 masks
C 172.16.10.0/24 is directly connected, Dot11Radio0/0/0
L 172.16.10.1/32 is directly connected, Dot11Radio0/0/0
D 192.168.10.0/24 [90/2174976] via 10.1.5.1, 00:31:10, FastEthernet0/0
D 192.168.20.0/24 [90/2174976] via 10.1.5.1, 00:31:02, FastEthernet0/0
via Corp and R1
D 192.168.30.0/24 [90/2174976] via 10.1.5.1, 00:13:28, FastEthernet0/0
D 192.168.40.0/24 [90/2174976] via 10.1.5.1, 00:13:05, FastEthernet0/0
via Corp and R2
S* 0.0.0.0/0 [1/0] via 10.1.5.1
------------------------------------------------------------------------------------------------------------------------------------
turn off auto summary on each router
------------------------------------------------------------------------------------------------------------------------------------
Corp(config)#
router eigrp 10
Corp(config-router)#
no auto-summary
------------------------------------------------------------------------------------------------------------------------------------
R1(config)#
router eigrp 10
R1(config-router)#
no auto-summary
------------------------------------------------------------------------------------------------------------------------------------
R2(config)#
router eigrp 10
R2(config-router)#
no auto-summary
------------------------------------------------------------------------------------------------------------------------------------
R3(config)#
router eigrp 10
R3(config-router)#
no auto-summary
------------------------------------------------------------------------------------------------------------------------------------
compare Corp before and after auto summary turned off
------------------------------------------------------------------------------------------------------------------------------------
auto summary on
Corp#
show ip route
Gateway of last resort is not set
10.0.0.0/8 is variably subnetted, 10 subnets, 2 masks
C 10.1.1.0/24 is directly connected, Vlan1
L 10.1.1.1/32 is directly connected, Vlan1
C 10.1.2.0/24 is directly connected, Serial0/0/0
L 10.1.2.1/32 is directly connected, Serial0/0/0
C 10.1.3.0/24 is directly connected, Serial0/0/1
L 10.1.3.1/32 is directly connected, Serial0/0/1
C 10.1.4.0/24 is directly connected, Serial0/1/0
L 10.1.4.1/32 is directly connected, Serial0/1/0
C 10.1.5.0/24 is directly connected, FastEthernet0/0
L 10.1.5.1/32 is directly connected, FastEthernet0/0
172.16.0.0/16 is variably subnetted, 2 subnets, 2 masks
R 172.16.0.0/16 [120/1] via 10.1.5.2, 00:00:17, FastEthernet0/0
D 172.16.10.0/24 [90/28160] via 10.1.5.2, 00:00:16, FastEthernet0/0
via R3
D 192.168.10.0/24 [90/2172416] via 10.1.2.2, 00:19:13, Serial0/0/0
[90/2172416] via 10.1.3.2, 00:19:13, Serial0/0/1
D 192.168.20.0/24 [90/2172416] via 10.1.3.2, 00:19:05, Serial0/0/1
[90/2172416] via 10.1.2.2, 00:19:05, Serial0/0/0
via R1
D 192.168.30.0/24 [90/2172416] via 10.1.4.2, 00:01:31, Serial0/1/0
D 192.168.40.0/24 [90/2172416] via 10.1.4.2, 00:01:08, Serial0/1/0
via R2
auto summary off
Corp#
show ip route
Gateway of last resort is not set
10.0.0.0/8 is variably subnetted, 10 subnets, 2 masks
C 10.1.1.0/24 is directly connected, Vlan1
L 10.1.1.1/32 is directly connected, Vlan1
C 10.1.2.0/24 is directly connected, Serial0/0/0
L 10.1.2.1/32 is directly connected, Serial0/0/0
C 10.1.3.0/24 is directly connected, Serial0/0/1
L 10.1.3.1/32 is directly connected, Serial0/0/1
C 10.1.4.0/24 is directly connected, Serial0/1/0
L 10.1.4.1/32 is directly connected, Serial0/1/0
C 10.1.5.0/24 is directly connected, FastEthernet0/0
L 10.1.5.1/32 is directly connected, FastEthernet0/0
172.16.0.0/16 is variably subnetted, 2 subnets, 2 masks
R 172.16.0.0/16 [120/1] via 10.1.5.2, 00:00:12, FastEthernet0/0
D 172.16.10.0/24 [90/28160] via 10.1.5.2, 00:45:29, FastEthernet0/0
via R3
D 192.168.10.0/24 [90/2172416] via 10.1.2.2, 00:01:08, Serial0/0/0
[90/2172416] via 10.1.3.2, 00:01:08, Serial0/0/1
D 192.168.20.0/24 [90/2172416] via 10.1.2.2, 00:01:08, Serial0/0/0
[90/2172416] via 10.1.3.2, 00:01:08, Serial0/0/1
via R1
D 192.168.30.0/24 [90/2172416] via 10.1.4.2, 00:00:46, Serial0/1/0
D 192.168.40.0/24 [90/2172416] via 10.1.4.2, 00:00:46, Serial0/1/0
via R2
We are still seeing an auto summarized route- 172.16.0.0 coming from R3.
The book discusses enabling EIGRP auto summary on all four routers- nothing is said about disabling it within RIP or turning off RIP.
RIP auto summarizes by default. We cant get rid of this auto summary route while RIP is on.
Moving on...
VERIFYING EIGRP
several commands available to verify and troubleshoot
show ip route
show the entire routing table
show ip route eigrp
show only EIGRP entries in the routing table
show ip eigrp neighbors
show all EIGRP neigbors
show ip eigrp topology
show entries in the EIGRP topology table
show ip protocols
shows routing protocols configuration
debug eigrp packet
shows hello packets sent/received between adjacent routers
debug ip eigrp events
shows EIGRP changes and updates as they occur on your network
lets take a look at the state of our 4 routers. RIP and EIGRP are running on each.
Notice how this command is giving different outputs between the two different IOS versions
IOS 15.1
Corp#
show ip protocols
Routing Protocol is "eigrp 10 "
Outgoing update filter list for all interfaces is not set
Incoming update filter list for all interfaces is not set
Default networks flagged in outgoing updates
Default networks accepted from incoming updates
Redistributing: eigrp 10
EIGRP-IPv4 Protocol for AS(10)
Metric weight K1=1, K2=0, K3=1, K4=0, K5=0
NSF-aware route hold timer is 240
Router-ID: 10.1.1.1
Topology : 0 (base)
Active Timer: 3 min
Distance: internal 90 external 170
Maximum path: 4
Maximum hopcount 100
Maximum metric variance 1
Automatic Summarization: disabled
Automatic address summarization:
Maximum path: 4
Routing for Networks:
10.0.0.0
Routing Information Sources:
Gateway Distance Last Update
10.1.5.2 90 0
10.1.3.2 90 6464
10.1.2.2 90 6795
10.1.4.2 90 7955
Distance: internal 90 external 170
Routing Protocol is "rip"
Sending updates every 30 seconds, next due in 10 seconds
Invalid after 180 seconds, hold down 180, flushed after 240
Outgoing update filter list for all interfaces is not set
Incoming update filter list for all interfaces is not set
Redistributing: rip
Default version control: send version 2, receive 2
Interface Send Recv Triggered RIP Key-chain
Vlan1 2 2
FastEthernet0/0 2 2
Serial0/1/0 2 2
Serial0/0/1 2 2
Serial0/0/0 2 2
Automatic network summarization is in effect
Maximum path: 4
Routing for Networks:
10.0.0.0
Passive Interface(s):
Routing Information Sources:
Gateway Distance Last Update
10.1.5.2 120 00:00:12
10.1.3.2 120 00:00:16
10.1.2.2 120 00:00:16
10.1.4.2 120 00:00:13
Distance: (default is 120)
IOS 12.4
R1#
show ip protocols
Routing Protocol is "eigrp 10 "
Outgoing update filter list for all interfaces is not set
Incoming update filter list for all interfaces is not set
Default networks flagged in outgoing updates
Default networks accepted from incoming updates
EIGRP metric weight K1=1, K2=0, K3=1, K4=0, K5=0
EIGRP maximum hopcount 100
EIGRP maximum metric variance 1
Redistributing: eigrp 10
Automatic network summarization is not in effect
Maximum path: 4
Routing for Networks:
10.0.0.0
192.168.10.0
192.168.20.0
Routing Information Sources:
Gateway Distance Last Update
10.1.3.1 90 6465
10.1.2.1 90 6794
Distance: internal 90 external 170
Routing Protocol is "rip"
Sending updates every 30 seconds, next due in 21 seconds
Invalid after 180 seconds, hold down 180, flushed after 240
Outgoing update filter list for all interfaces is not set
Incoming update filter list for all interfaces is not set
Redistributing: rip
Default version control: send version 2, receive 2
Interface Send Recv Triggered RIP Key-chain
FastEthernet0/0 2 2
FastEthernet0/1 2 2
Serial0/0/0 2 2
Serial0/0/1 2 2
Automatic network summarization is not in effect
Maximum path: 4
Routing for Networks:
10.0.0.0
192.168.10.0
192.168.20.0
Passive Interface(s):
Routing Information Sources:
Gateway Distance Last Update
10.1.3.1 120 00:00:06
10.1.2.1 120 00:00:06
Distance: (default is 120)
IOS 12.4
R2#
show ip protocols
Routing Protocol is "eigrp 10 "
Outgoing update filter list for all interfaces is not set
Incoming update filter list for all interfaces is not set
Default networks flagged in outgoing updates
Default networks accepted from incoming updates
EIGRP metric weight K1=1, K2=0, K3=1, K4=0, K5=0
EIGRP maximum hopcount 100
EIGRP maximum metric variance 1
Redistributing: eigrp 10
Automatic network summarization is not in effect
Maximum path: 4
Routing for Networks:
10.0.0.0
192.168.30.0
192.168.40.0
Routing Information Sources:
Gateway Distance Last Update
10.1.4.1 90 7955
Distance: internal 90 external 170
Routing Protocol is "rip"
Sending updates every 30 seconds, next due in 11 seconds
Invalid after 180 seconds, hold down 180, flushed after 240
Outgoing update filter list for all interfaces is not set
Incoming update filter list for all interfaces is not set
Redistributing: rip
Default version control: send version 2, receive 2
Interface Send Recv Triggered RIP Key-chain
FastEthernet0/0 2 2
FastEthernet0/1 2 2
Serial0/0/0 2 2
Automatic network summarization is in effect
Maximum path: 4
Routing for Networks:
10.0.0.0
192.168.30.0
192.168.40.0
Passive Interface(s):
Routing Information Sources:
Gateway Distance Last Update
10.1.4.1 120 00:00:20
Distance: (default is 120)
IOS 15.1
R3#
show ip protocols
Routing Protocol is "eigrp 10 "
Outgoing update filter list for all interfaces is not set
Incoming update filter list for all interfaces is not set
Default networks flagged in outgoing updates
Default networks accepted from incoming updates
Redistributing: eigrp 10
EIGRP-IPv4 Protocol for AS(10)
Metric weight K1=1, K2=0, K3=1, K4=0, K5=0
NSF-aware route hold timer is 240
Router-ID: 10.1.5.2
Topology : 0 (base)
Active Timer: 3 min
Distance: internal 90 external 170
Maximum path: 4
Maximum hopcount 100
Maximum metric variance 1
Automatic Summarization: disabled
Automatic address summarization:
Maximum path: 4
Routing for Networks:
10.0.0.0
172.16.0.0
Routing Information Sources:
Gateway Distance Last Update
10.1.5.1 90 0
Distance: internal 90 external 170
Routing Protocol is "rip"
Sending updates every 30 seconds, next due in 27 seconds
Invalid after 180 seconds, hold down 180, flushed after 240
Outgoing update filter list for all interfaces is not set
Incoming update filter list for all interfaces is not set
Redistributing: rip
Default version control: send version 2, receive 2
Interface Send Recv Triggered RIP Key-chain
Dot11Radio0/0/0 2 2
FastEthernet0/0 2 2
Automatic network summarization is not in effect
Maximum path: 4
Routing for Networks:
10.0.0.0
172.16.0.0
Passive Interface(s):
Routing Information Sources:
Gateway Distance Last Update
10.1.5.1 120 00:00:02
Distance: (default is 120)
I'm also noticing that we have inconsistent auto-summarization settings- I was having trouble with this earlier. The book discusses
getting rid of the 172.16.0.0 summarized route in the EIGRP settings. I was not able to get rid of it, I think because RIP is still on, and RIP forces auto-summary
Part of the challenge here is that the book is strictly dealing with IOS 12.4
I will now make sure to turn auto summary off for both RIP and EIGRP on each of the four routers.
OK the part I am forgetting is that we are running RIP V2 which does not force auto-summary but runs it optionally, and we must turn it off to avoid auto summarization.
Corp(config)#
router rip
Corp(config-router)#
no auto-summary
Corp(config-router)#
router eigrp 10
Corp(config-router)#
no auto-summary
R1(config)#
router rip
R1(config-router)#
no auto-summary
R1(config-router)#
router eigrp 10
R1(config-router)#
no auto-summary
R1(config)#
router rip
R1(config-router)#
no auto-summary
R1(config-router)#
router eigrp 10
R2(config-router)#
no auto-summary
R3(config)#
router rip
R3(config-router)#
no auto-summary
R3(config-router)#
router eigrp 10
R3(config-router)#
no auto-summary
and lets see how the output looks now. This time I'll do show ip protocols and
show ip route side by side for each router
IOS 15.1
Corp#
show ip protocols
Routing Protocol is "eigrp 10 "
Outgoing update filter list for all interfaces is not set
Incoming update filter list for all interfaces is not set
Default networks flagged in outgoing updates
Default networks accepted from incoming updates
Redistributing: eigrp 10
EIGRP-IPv4 Protocol for AS(10)
Metric weight K1=1, K2=0, K3=1, K4=0, K5=0
NSF-aware route hold timer is 240
Router-ID: 10.1.1.1
Topology : 0 (base)
Active Timer: 3 min
Distance: internal 90 external 170
Maximum path: 4
Maximum hopcount 100
Maximum metric variance 1
Automatic Summarization: disabled
Automatic address summarization:
Maximum path: 4
Routing for Networks:
10.0.0.0
Routing Information Sources:
Gateway Distance Last Update
10.1.5.2 90 0
10.1.3.2 90 6464
10.1.2.2 90 6795
10.1.4.2 90 7955
Distance: internal 90 external 170
Routing Protocol is "rip" doesnt necessarily mean RIPv1
Sending updates every 30 seconds, next due in 3 seconds
Invalid after 180 seconds, hold down 180, flushed after 240
Outgoing update filter list for all interfaces is not set
Incoming update filter list for all interfaces is not set
Redistributing: rip
Default version control: send version 2, receive 2 RIPv2 is specified
Interface Send Recv Triggered RIP Key-chain
Vlan1 2 2
FastEthernet0/0 2 2
Serial0/1/0 2 2
Serial0/0/1 2 2
Serial0/0/0 2 2
Automatic network summarization is not in effect
Maximum path: 4
Routing for Networks:
10.0.0.0
Passive Interface(s):
Routing Information Sources:
Gateway Distance Last Update
10.1.5.2 120 00:00:02
10.1.3.2 120 00:00:21
10.1.2.2 120 00:00:21
10.1.4.2 120 00:00:04
Distance: (default is 120)
IOS 15.1
Corp#
show ip route
Gateway of last resort is not set
10.0.0.0/8 is variably subnetted, 10 subnets, 2 masks
C 10.1.1.0/24 is directly connected, Vlan1
L 10.1.1.1/32 is directly connected, Vlan1
C 10.1.2.0/24 is directly connected, Serial0/0/0
L 10.1.2.1/32 is directly connected, Serial0/0/0
C 10.1.3.0/24 is directly connected, Serial0/0/1
L 10.1.3.1/32 is directly connected, Serial0/0/1
C 10.1.4.0/24 is directly connected, Serial0/1/0
L 10.1.4.1/32 is directly connected, Serial0/1/0
C 10.1.5.0/24 is directly connected, FastEthernet0/0
L 10.1.5.1/32 is directly connected, FastEthernet0/0
172.16.0.0/24 is subnetted, 1 subnets
D 172.16.10.0/24 [90/28160] via 10.1.5.2, 00:57:25, FastEthernet0/0
D 192.168.10.0/24 [90/2172416] via 10.1.3.2, 00:57:20, Serial0/0/1
[90/2172416] via 10.1.2.2, 00:57:20, Serial0/0/0
D 192.168.20.0/24 [90/2172416] via 10.1.3.2, 00:57:20, Serial0/0/1
[90/2172416] via 10.1.2.2, 00:57:20, Serial0/0/0
D 192.168.30.0/24 [90/2172416] via 10.1.4.2, 00:57:19, Serial0/1/0
D 192.168.40.0/24 [90/2172416] via 10.1.4.2, 00:57:19, Serial0/1/0
IOS 12.4
R1#
show ip protocols
Routing Protocol is "eigrp 10 "
Outgoing update filter list for all interfaces is not set
Incoming update filter list for all interfaces is not set
Default networks flagged in outgoing updates
Default networks accepted from incoming updates
EIGRP metric weight K1=1, K2=0, K3=1, K4=0, K5=0
EIGRP maximum hopcount 100
EIGRP maximum metric variance 1
Redistributing: eigrp 10
Automatic network summarization is not in effect
Maximum path: 4
Routing for Networks:
10.0.0.0
192.168.10.0
192.168.20.0
Routing Information Sources:
Gateway Distance Last Update
10.1.3.1 90 6465
10.1.2.1 90 6794
Distance: internal 90 external 170
Routing Protocol is "rip"
Sending updates every 30 seconds, next due in 26 seconds
Invalid after 180 seconds, hold down 180, flushed after 240
Outgoing update filter list for all interfaces is not set
Incoming update filter list for all interfaces is not set
Redistributing: rip
Default version control: send version 2, receive 2
Interface Send Recv Triggered RIP Key-chain
FastEthernet0/0 2 2
FastEthernet0/1 2 2
Serial0/0/0 2 2
Serial0/0/1 2 2
Automatic network summarization is not in effect
Maximum path: 4
Routing for Networks:
10.0.0.0
192.168.10.0
192.168.20.0
Passive Interface(s):
Routing Information Sources:
Gateway Distance Last Update
10.1.3.1 120 00:00:03
10.1.2.1 120 00:00:03
Distance: (default is 120)
IOS 12.4
R1#
show ip route
Gateway of last resort is not set
10.0.0.0/24 is subnetted, 5 subnets
D 10.1.1.0 [90/27769856] via 10.1.3.1, 00:54:47, Serial0/0/1
[90/27769856] via 10.1.2.1, 00:54:47, Serial0/0/0
C 10.1.2.0 is directly connected, Serial0/0/0
C 10.1.3.0 is directly connected, Serial0/0/1
D 10.1.4.0 [90/2681856] via 10.1.3.1, 00:54:47, Serial0/0/1
[90/2681856] via 10.1.2.1, 00:54:47, Serial0/0/0
D 10.1.5.0 [90/2172416] via 10.1.3.1, 00:54:47, Serial0/0/1
[90/2172416] via 10.1.2.1, 00:54:47, Serial0/0/0
172.16.0.0/24 is subnetted, 1 subnets
D 172.16.10.0 [90/2172416] via 10.1.3.1, 00:54:47, Serial0/0/1
[90/2172416] via 10.1.2.1, 00:54:47, Serial0/0/0
C 192.168.10.0/24 is directly connected, FastEthernet0/0
C 192.168.20.0/24 is directly connected, FastEthernet0/1
D 192.168.30.0/24 [90/2684416] via 10.1.3.1, 00:54:46, Serial0/0/1
[90/2684416] via 10.1.2.1, 00:54:46, Serial0/0/0
D 192.168.40.0/24 [90/2684416] via 10.1.3.1, 00:54:46, Serial0/0/1
[90/2684416] via 10.1.2.1, 00:54:46, Serial0/0/0
note that the DUAL routes being advertised from the 10.0.0.0 networks are all specific to the third octet.. that's because we are reading those routes
from their source, aka the router which they are directly connected to, Corp.
and on Corp, those networks were added to the interfaces with a /24 mask.
so even though our EIGRP config doesnt specifically include /24 networks.. we told it to include anything with a 10.x.x.x
Corp is advertising to R1 our /24 network interfaces that have a 10 in the first octet, EXCEPT the two which are directly connected to R1
10.1.1.0
10.1.4.0
10.1.5.0
are assumed to be the subnets based on the info we configured, which was 10.1.4.1/24 on corp, and 10.1.4.2/24 on r2 s0/0/0
nowhere in this configuration, have we entered the 10.1.4.0 network.
EIGRP is figuring it out based on the /24 mask we gave when assiging he IPs to the interfaces
IOS 12.4
R2#
show ip protocols
Routing Protocol is "eigrp 10 "
Outgoing update filter list for all interfaces is not set
Incoming update filter list for all interfaces is not set
Default networks flagged in outgoing updates
Default networks accepted from incoming updates
EIGRP metric weight K1=1, K2=0, K3=1, K4=0, K5=0
EIGRP maximum hopcount 100
EIGRP maximum metric variance 1
Redistributing: eigrp 10
Automatic network summarization is not in effect
Maximum path: 4
Routing for Networks:
10.0.0.0
192.168.30.0
192.168.40.0
Routing Information Sources:
Gateway Distance Last Update
10.1.4.1 90 7955
Distance: internal 90 external 170
Routing Protocol is "rip"
Sending updates every 30 seconds, next due in 18 seconds
Invalid after 180 seconds, hold down 180, flushed after 240
Outgoing update filter list for all interfaces is not set
Incoming update filter list for all interfaces is not set
Redistributing: rip
Default version control: send version 2, receive 2
Interface Send Recv Triggered RIP Key-chain
FastEthernet0/0 2 2
FastEthernet0/1 2 2
Serial0/0/0 2 2
Automatic network summarization is not in effect
Maximum path: 4
Routing for Networks:
10.0.0.0
192.168.30.0
192.168.40.0
Passive Interface(s):
Routing Information Sources:
Gateway Distance Last Update
10.1.4.1 120 00:00:07
Distance: (default is 120)
IOS 12.4
R2#
show ip route
Gateway of last resort is not set
10.0.0.0/24 is subnetted, 5 subnets
D 10.1.1.0 [90/27769856] via 10.1.4.1, 00:59:10, Serial0/0/0
D 10.1.2.0 [90/2681856] via 10.1.4.1, 00:59:10, Serial0/0/0
D 10.1.3.0 [90/2681856] via 10.1.4.1, 00:59:10, Serial0/0/0
C 10.1.4.0 is directly connected, Serial0/0/0
D 10.1.5.0 [90/2172416] via 10.1.4.1, 00:59:10, Serial0/0/0
172.16.0.0/24 is subnetted, 1 subnets
D 172.16.10.0 [90/2172416] via 10.1.4.1, 00:59:10, Serial0/0/0
D 192.168.10.0/24 [90/2684416] via 10.1.4.1, 00:59:10, Serial0/0/0
D 192.168.20.0/24 [90/2684416] via 10.1.4.1, 00:59:10, Serial0/0/0
C 192.168.30.0/24 is directly connected, FastEthernet0/0
C 192.168.40.0/24 is directly connected, FastEthernet0/1
IOS 15.1
R3#
show ip protocols
Routing Protocol is "eigrp 10 "
Outgoing update filter list for all interfaces is not set
Incoming update filter list for all interfaces is not set
Default networks flagged in outgoing updates
Default networks accepted from incoming updates
Redistributing: eigrp 10
EIGRP-IPv4 Protocol for AS(10)
Metric weight K1=1, K2=0, K3=1, K4=0, K5=0
NSF-aware route hold timer is 240
Router-ID: 10.1.5.2
Topology : 0 (base)
Active Timer: 3 min
Distance: internal 90 external 170
Maximum path: 4
Maximum hopcount 100
Maximum metric variance 1
Automatic Summarization: disabled
Automatic address summarization:
Maximum path: 4
Routing for Networks:
10.0.0.0
172.16.0.0
Routing Information Sources:
Gateway Distance Last Update
10.1.5.1 90 0
Distance: internal 90 external 170
Routing Protocol is "rip"
Sending updates every 30 seconds, next due in 15 seconds
Invalid after 180 seconds, hold down 180, flushed after 240
Outgoing update filter list for all interfaces is not set
Incoming update filter list for all interfaces is not set
Redistributing: rip
Default version control: send version 2, receive 2
Interface Send Recv Triggered RIP Key-chain
Dot11Radio0/0/0 2 2
FastEthernet0/0 2 2
Automatic network summarization is not in effect
Maximum path: 4
Routing for Networks:
10.0.0.0
172.16.0.0
Passive Interface(s):
Routing Information Sources:
Gateway Distance Last Update
10.1.5.1 120 00:00:14
Distance: (default is 120)
IOS 15.1
R3#
show ip route
Gateway of last resort is 10.1.5.1 to network 0.0.0.0
10.0.0.0/8 is variably subnetted, 6 subnets, 2 masks
D 10.1.1.0/24 [90/25628160] via 10.1.5.1, 00:59:52, FastEthernet0/0
D 10.1.2.0/24 [90/2172416] via 10.1.5.1, 00:59:47, FastEthernet0/0
D 10.1.3.0/24 [90/2172416] via 10.1.5.1, 00:59:52, FastEthernet0/0
D 10.1.4.0/24 [90/2172416] via 10.1.5.1, 00:59:52, FastEthernet0/0
C 10.1.5.0/24 is directly connected, FastEthernet0/0
L 10.1.5.2/32 is directly connected, FastEthernet0/0
172.16.0.0/16 is variably subnetted, 2 subnets, 2 masks
C 172.16.10.0/24 is directly connected, Dot11Radio0/0/0
L 172.16.10.1/32 is directly connected, Dot11Radio0/0/0
D 192.168.10.0/24 [90/2174976] via 10.1.5.1, 00:59:47, FastEthernet0/0
D 192.168.20.0/24 [90/2174976] via 10.1.5.1, 00:59:47, FastEthernet0/0
D 192.168.30.0/24 [90/2174976] via 10.1.5.1, 00:59:46, FastEthernet0/0
D 192.168.40.0/24 [90/2174976] via 10.1.5.1, 00:59:46, FastEthernet0/0
S* 0.0.0.0/0 [1/0] via 10.1.5.1
Observations:
Since this is a 15.1 router, we always get a "L" local route when
we have a "C" connected route. In R3's case, the 172.16.10.0 network
is directly connected. The interface which connects it, 172.16.10.1,
counts as a "local" route. This is NOT the case on the 12.4 routers.
looking to the left, our protocol output tells us two key facts for both EIGRP and RIP:
Routing for networks:
10.0.0.0
172.16.0.0
R3 is responsible for *sending* data about these two networks to our other EIGRP routers...
"I'm R3 and I can connect you to networks on the R3
router or networks on the Corp router"
Notice how the 192 networks arent listed. R3 isnt connected to a 192 network directly, nor is it connected to a neighbor who is directly connected.
If I, as a client, am sending data to a 192 network from the 172 network, I will start
at R3. Since R3 is receiving routes for the 192 networks via Corp, I will be able to reach a 192 network via Corp.
My connection to corp will happen VIA a "10.0.0.0" route.
R3 is technically only routing for 172 and 10 networks. Beyond that, it could potentially connect to many other different networks. But in terms of the R3 routing table,
all it can offer is a path out to the 172 network or the 10 network
Routing information sources:
10.1.5.1
In this case I can see that R3 is receiving routing data from one interface only,
and that is it's link to Corp. Some of the data we are receiving from Corp actually originates
at other routers, but we cant see that here; the data comes to us from Corp, and that is all we know
EIGRP TERMINOLOGY
FEASIBLE DISTANCE (FD)
the best metric among all paths, including to the next hop neighbor. You will only see the route with the lowest FD appear in the routing table
The FD is calculated by adding the reported distance from the neighbor (AD) plus the metric to that neighbor
ADVERTISED DISTANCE (AD)
the metric of a remote network as reported by a neighbor, listed second in parenthesis in toplogy table
P 192.168.20.0/24, 2 successors, FD is 2172416
via 10.1.3.2 (2172416/28160), Serial0/0/1
feasible / advertised
Neighbor Table
each router keeps state information about adjacent neighbors.. When a new neighbor is learned, the address and interface are recorded.
The neighbor table is stored in RAM.
Sequence numbres are used to match acks with update packets. The last squence number received from a neighbor is recorded so out of order packets
can be detected
Topology Table
acted upon by DUAL Diffusing Update Alogorithm. Contains all destinations advertised by neighboring routers.
For each neighbor, the adversited distance, which comes only from that neighbor's routing table, is recorded
The feasible distance is also recorded.
Feasible Successor
a PATH whose advertised distance is less than the feasible distance of the current succesor, and is considered a backup route.
EIGRP keeps up to 16 feasible successors in the toplogy table.
The one with the best metric (The Successor) is copied and placed into the routing table
Successor
the best route to a remote network, used by EIGRP to forward traffic. It's backed up by a feasible successor, if one is available.
lets demo some more of the commands
VERIFYING EIGRP
several commands available to verify and troubleshoot
show ip route
show the entire routing table
show ip route eigrp
show only EIGRP entries in the routing table
show ip eigrp neighbors
show all EIGRP neigbors
show ip eigrp topology
show entries in the EIGRP topology table
show ip protocols
shows routing protocols configuration
debug eigrp packet
shows hello packets sent/received between adjacent routers
debug ip eigrp events
shows EIGRP changes and updates as they occur on your network
Corp#
show ip eigrp ?
interfaces IP-EIGRP interfaces
neighbors IP-EIGRP neighbors
topology IP-EIGRP Topology Table
traffic IP-EIGRP Traffic Statistics
Corp#
show ip eigrp topology
IP-EIGRP Topology Table for AS 10/ID(10.1.5.1)
Codes: P - Passive, A - Active, U - Update, Q - Query, R - Reply,
r - Reply status
P 10.1.1.0/24, 1 successors, FD is 25625600
via Connected, Vlan1
P 10.1.2.0/24, 1 successors, FD is 2169856
via Connected, Serial0/0/0
P 10.1.3.0/24, 1 successors, FD is 2169856
via Connected, Serial0/0/1
P 10.1.4.0/24, 1 successors, FD is 2169856
via Connected, Serial0/1/0
P 10.1.5.0/24, 1 successors, FD is 28160
via Connected, FastEthernet0/0
P 172.16.10.0/24, 1 successors, FD is 28160
via 10.1.5.2 (28160/25600), FastEthernet0/0
P 192.168.10.0/24, 2 successors, FD is 2172416
via 10.1.3.2 (2172416/28160), Serial0/0/1
via 10.1.2.2 (2172416/28160), Serial0/0/0
P 192.168.20.0/24, 2 successors, FD is 2172416
via 10.1.3.2 (2172416/28160), Serial0/0/1
via 10.1.2.2 (2172416/28160), Serial0/0/0
P 192.168.30.0/24, 1 successors, FD is 2172416
via 10.1.4.2 (2172416/28160), Serial0/1/0
P 192.168.40.0/24, 1 successors, FD is 2172416
via 10.1.4.2 (2172416/28160), Serial0/1/0
the "P" preceding each entry is for PASSIVE
these routes are in a passive state, which is good
if they move to an ACTIVE state, it means the have lost their path in the network and looking for a replacement.
Each entry also shows the FEASIBLE DISTANCE, the next hop address, and the local egress interface
Corp#
show ip eigrp neighbors
IP-EIGRP neighbors for process 10
H Address Interface Hold Uptime SRTT RTO Q Seq
(sec) (ms) Cnt Num
0 10.1.5.2 Fa0/0 14 02:00:05 40 1000 0 19
1 10.1.3.2 Se0/0/1 13 01:59:59 40 1000 0 14
2 10.1.2.2 Se0/0/0 13 01:59:59 40 1000 0 13
3 10.1.4.2 Se0/1/0 12 01:59:57 40 1000 0 15
fields:
H - the order in which the neighbors were discovered
hold - how long the router will wait for a hello packet
uptime - how long the neigborship has been established
SRTT - smooth round trip timer - the time it takes for a round trip from this router, to neighbor, and back.
SRTT is used to determine how long to wait for a MULTICAST reply.
if a reply isnt received in time, the router switches to UNICASTS
RTO - Retransmission Time Out- is the time EIGRP waits before retransmitting a packet from the retransmission queue
Q - indicates wheter there are oustanding messages in the queue
Seq - indicates the sequence number of the last update from that neighbor. This is used to maintain syncrhonization and avoid duplicate
or out-of-sequence processing of messages
Corp#
show ip route eigrp
172.16.0.0/24 is subnetted, 1 subnets
D 172.16.10.0 [90/28160] via 10.1.5.2, 02:08:04, FastEthernet0/0
D 192.168.10.0/24 [90/2172416] via 10.1.3.2, 02:07:59, Serial0/0/1
[90/2172416] via 10.1.2.2, 02:07:59, Serial0/0/0
D 192.168.20.0/24 [90/2172416] via 10.1.3.2, 02:07:59, Serial0/0/1
[90/2172416] via 10.1.2.2, 02:07:59, Serial0/0/0
D 192.168.30.0/24 [90/2172416] via 10.1.4.2, 02:07:58, Serial0/1/0
D 192.168.40.0/24 [90/2172416] via 10.1.4.2, 02:07:58, Serial0/1/0
Corp#
show ip eigrp interfaces
IP-EIGRP interfaces for process 10
Xmit Queue Mean Pacing Time Multicast Pending
Interface Peers Un/Reliable SRTT Un/Reliable Flow Timer Routes
Vlan 0 0/0 1236 0/10 0 0
Fa0/0 1 0/0 1236 0/10 0 0
Se0/1/0 1 0/0 1236 0/10 0 0
Se0/0/1 1 0/0 1236 0/10 0 0
Se0/0/0 1 0/0 1236 0/10 0 0
Corp#
show ip protocols
Routing Protocol is "eigrp 10 "
Outgoing update filter list for all interfaces is not set
Incoming update filter list for all interfaces is not set
Default networks flagged in outgoing updates
Default networks accepted from incoming updates
Redistributing: eigrp 10
EIGRP-IPv4 Protocol for AS(10)
Metric weight K1=1, K2=0, K3=1, K4=0, K5=0 using K1 bandwidth and K2 delay by default
NSF-aware route hold timer is 240
Router-ID: 10.1.1.1
Topology : 0 (base)
Active Timer: 3 min
Distance: internal 90 external 170
Maximum path: 4
Maximum hopcount 100
Maximum metric variance 1
Automatic Summarization: disabled
Automatic address summarization:
Maximum path: 4
Routing for Networks:
10.0.0.0
Routing Information Sources:
Gateway Distance Last Update
10.1.5.2 90 0
10.1.3.2 90 8936
10.1.4.2 90 9511
10.1.2.2 90 9597
Distance: internal 90 external 170
Routing Protocol is "rip"
Sending updates every 30 seconds, next due in 13 seconds
Invalid after 180 seconds, hold down 180, flushed after 240
Outgoing update filter list for all interfaces is not set
Incoming update filter list for all interfaces is not set
Redistributing: rip
Default version control: send version 2, receive 2
Interface Send Recv Triggered RIP Key-chain
Vlan1 2 2
FastEthernet0/0 2 2
Serial0/0/1 2 2
Serial0/1/0 2 2
Serial0/0/0 2 2
Automatic network summarization is not in effect
Maximum path: 4
Routing for Networks:
10.0.0.0
Passive Interface(s):
Routing Information Sources:
Gateway Distance Last Update
10.1.5.2 120 00:00:05
10.1.3.2 120 00:00:12
10.1.2.2 120 00:00:12
10.1.4.2 120 00:00:17
Distance: (default is 120)
corp#
debug eigrp packet
break into two columns for readability
Observations:
There doesnt appear to be a pattern in the order each router is addressed, except that the TO's and FROM"s are grouped together
The TO messages dont show the destination IP, only the egress local interface
The FROM messages do show the remote IP, as well as the local ingress interface
Corp#
EIGRP: Received HELLO on FastEthernet0/0 nbr 10.1.5.2
AS 10, Flags 0x0, Seq 18/0 idbQ 0/0
hello from R3
Corp#
EIGRP: Received HELLO on Serial0/1/0 nbr 10.1.4.2
AS 10, Flags 0x0, Seq 16/0 idbQ 0/0
hello from R2
Corp#
EIGRP: Received HELLO on Serial0/0/0 nbr 10.1.2.2
AS 10, Flags 0x0, Seq 19/0 idbQ 0/0
hello from R1
------------------------------------------------------------
Corp#
EIGRP: Sending HELLO on Serial0/1/0
AS 10, Flags 0x0, Seq 21/0 idbQ 0/0 iidbQ un/rely 0/0
hello to R2
Corp#
EIGRP: Sending HELLO on FastEthernet0/0
AS 10, Flags 0x0, Seq 21/0 idbQ 0/0 iidbQ un/rely 0/0
hello to R3
Corp#
EIGRP: Sending HELLO on Serial0/0/1
AS 10, Flags 0x0, Seq 21/0 idbQ 0/0 iidbQ un/rely 0/0
hello to R1
Corp#
EIGRP: Sending HELLO on Serial0/0/0
AS 10, Flags 0x0, Seq 21/0 idbQ 0/0 iidbQ un/rely 0/0
hello to R1
Corp#
EIGRP: Sending HELLO on Vlan1
AS 10, Flags 0x0, Seq 21/0 idbQ 0/0 iidbQ un/rely 0/0
hello to switch card (not a router....)
------------------------------------------------------------
Corp#
EIGRP: Received HELLO on Serial0/0/1 nbr 10.1.3.2
AS 10, Flags 0x0, Seq 19/0 idbQ 0/0
hello from R1
Corp#
EIGRP: Received HELLO on FastEthernet0/0 nbr 10.1.5.2
AS 10, Flags 0x0, Seq 18/0 idbQ 0/0
hello from R3
Corp#
EIGRP: Received HELLO on Serial0/0/0 nbr 10.1.2.2
AS 10, Flags 0x0, Seq 19/0 idbQ 0/0
hello from R1
Corp#
EIGRP: Received HELLO on Serial0/1/0 nbr 10.1.4.2
AS 10, Flags 0x0, Seq 16/0 idbQ 0/0
hello from R2
------------------------------------------------------------
Corp#
EIGRP: Sending HELLO on Serial0/1/0
AS 10, Flags 0x0, Seq 21/0 idbQ 0/0 iidbQ un/rely 0/0
hello to R2... no neighbor IP?
Corp#
EIGRP: Sending HELLO on Serial0/0/0
AS 10, Flags 0x0, Seq 21/0 idbQ 0/0 iidbQ un/rely 0/0
hello to R1... no neighbor IP?
Corp#
EIGRP: Sending HELLO on FastEthernet0/0
AS 10, Flags 0x0, Seq 21/0 idbQ 0/0 iidbQ un/rely 0/0
hello to R3... no neighbor IP?
Corp#
EIGRP: Sending HELLO on Serial0/0/1
AS 10, Flags 0x0, Seq 21/0 idbQ 0/0 iidbQ un/rely 0/0
hello to R1
Corp#
EIGRP: Sending HELLO on Vlan1
AS 10, Flags 0x0, Seq 21/0 idbQ 0/0 iidbQ un/rely 0/0
hello to switch card (not a router)
------------------------------------------------------------
OUTPUT CONTINUES IN NEXT COLUMN
Corp#
EIGRP: Received HELLO on Serial0/0/1 nbr 10.1.3.2
AS 10, Flags 0x0, Seq 19/0 idbQ 0/0
hello from R1
Corp#
EIGRP: Received HELLO on FastEthernet0/0 nbr 10.1.5.2
AS 10, Flags 0x0, Seq 18/0 idbQ 0/0
hello from R3
Corp#
EIGRP: Received HELLO on Serial0/0/0 nbr 10.1.2.2
AS 10, Flags 0x0, Seq 19/0 idbQ 0/0
hello from R1
Corp#
EIGRP: Received HELLO on Serial0/1/0 nbr 10.1.4.2
AS 10, Flags 0x0, Seq 16/0 idbQ 0/0
hello from R2
------------------------------------------------------------
Corp#
EIGRP: Sending HELLO on Serial0/1/0
AS 10, Flags 0x0, Seq 21/0 idbQ 0/0 iidbQ un/rely 0/0
hello to R2
Corp#
EIGRP: Sending HELLO on Serial0/0/0
AS 10, Flags 0x0, Seq 21/0 idbQ 0/0 iidbQ un/rely 0/0
hello to R1
Corp#
EIGRP: Sending HELLO on Vlan1
AS 10, Flags 0x0, Seq 21/0 idbQ 0/0 iidbQ un/rely 0/0
hello to Corp switchcard
Corp#
EIGRP: Sending HELLO on Serial0/0/1
AS 10, Flags 0x0, Seq 21/0 idbQ 0/0 iidbQ un/rely 0/0
hello to R1
Corp#
EIGRP: Sending HELLO on FastEthernet0/0
AS 10, Flags 0x0, Seq 21/0 idbQ 0/0 iidbQ un/rely 0/0
hello to R3... no neighbor IP?
------------------------------------------------------------
Corp#
EIGRP: Received HELLO on Serial0/0/1 nbr 10.1.3.2
AS 10, Flags 0x0, Seq 19/0 idbQ 0/0
hello from R1
Corp#
EIGRP: Received HELLO on FastEthernet0/0 nbr 10.1.5.2
AS 10, Flags 0x0, Seq 18/0 idbQ 0/0
hello from R3
Corp#
EIGRP: Received HELLO on Serial0/1/0 nbr 10.1.4.2
AS 10, Flags 0x0, Seq 16/0 idbQ 0/0
hello from R2
Corp#
EIGRP: Received HELLO on Serial0/0/0 nbr 10.1.2.2
AS 10, Flags 0x0, Seq 19/0 idbQ 0/0
hello from R1
------------------------------------------------------------
Corp#
EIGRP: Sending HELLO on Serial0/1/0
AS 10, Flags 0x0, Seq 21/0 idbQ 0/0 iidbQ un/rely 0/0
hello to R2
Corp#
EIGRP: Sending HELLO on Vlan1
AS 10, Flags 0x0, Seq 21/0 idbQ 0/0 iidbQ un/rely 0/0
hello to Corp switchcard
EIGRP: Sending HELLO on Serial0/0/0
AS 10, Flags 0x0, Seq 21/0 idbQ 0/0 iidbQ un/rely 0/0
hello to R1
EIGRP: Sending HELLO on Serial0/0/1
AS 10, Flags 0x0, Seq 21/0 idbQ 0/0 iidbQ un/rely 0/0
hello to R1
Corp#
EIGRP: Sending HELLO on FastEthernet0/0
AS 10, Flags 0x0, Seq 21/0 idbQ 0/0 iidbQ un/rely 0/0
hello to R3
------------------------------------------------------------
Now some videos. To reinforce EIGRP concepts, and lead into OSPF
OSPF - OPEN SHORTEST PATH FIRST
Before enabling OSPF, we'll turn off RIP and EIGRP on all four routers.
Device(config)#
no router eigrp 10
Device(config)#
no router rip
The OSPF configs for the local egress ip address
Corp(config)#
router ospf 132
Corp(config)#
network 10.1.0.0 0.0.255.255 area 0
R1(config)#
router ospf 1
R1(config)#
network 10.1.0.0 0.0.255.255 area 0
R1(config)#
network 192.168.0.0 0.0.255.255 area 0
R2(config)#
router ospf 45678
R2(config)#
network 10.0.0.0 0.0.0.255 area 0
R2(config)#
network 192.168.30.1 0.0.0.0 area 0
R2(config)#
network 192.168.40.1 0.0.0.0 area 0
all 32 bits of the mask are specified for the 192 entries;
these are not network id's, they are HOST id's of the specific interfaces, which are EGRESS interfaces on the router we are configuring
R3(config)#
router ospf 1
R2(config)#
network 10.1.5.2 0.0.0.255 area 0
R2(config)#
network 172.16.10.0 0.0.0.255 area 0
Wildcard Masks
these notes are not intended to be a precise explanation of wlidcard masking, but rather a look into my thought process as I am learning the concept.
resources:
traceroute blog examples
routerjockey blog examples
subnetonline wildcard calculator
Ch 9 Exam Essentials
1. Know EIGRP features
classless (like RipV2 and OSPF)
distance vector
supports IP, IPX, appleTalk, IPV6
supports summaries and discontiguous networks
uses the Diffusing Update Algorithm (DUAL) to maintain route information
uses RTP to communicate with other EIGRP routers
uses the concept of an autonomous system to describe the set of contiguous routers that run the same routing protocol and share routing information
considered CLASSLESS- includes the subnet mask in its route updates
sends traditional distance-vector updates containing info about networks plus the cost of reaching them from the perspective of the advertising router
but not strictly distance-vector. Has link-state characteristics: synchronizes routing tables between neighbors at startup and then sends specific updates only when topology changes.
max hop count of 255 (default is 100)
but hop count is NOT a metric, like in RIP. Hop count is how many routers an EIGRP route update can traverse before being discarded. This limits the size of the AS.
2. Know how to configure EIGRP
the router eigrp [as] command turns EIGRP routing on in the router. Unlike RIPv1, EIGRP uses classless routing. BUT you can still configure as classful.
R1(config)#
router eigrp 10
enters router config mode
R1(config-router)#
network 10.0.0.0
on this router, interfaces that fall within 10.0.0.0 will advertise EIGRP info
3. Know how to verify EIGRP operation
Corp#
show ip
protocols
Corp#
show ip
route
Corp#
show ip
route eigrp
Corp#
show ip
eigrp neighbors
Corp#
show ip
eigrp topology
Corp#
show ip
eigrp interfaces
Corp#
show ip
protocols
info about all active routing protocols
Routing Protocol is "eigrp 10 "
Outgoing update filter list for all interfaces is not set
Incoming update filter list for all interfaces is not set
Default networks flagged in outgoing updates
Default networks accepted from incoming updates
Redistributing: eigrp 10
EIGRP-IPv4 Protocol for AS(10)
Metric weight K1=1, K2=0, K3=1, K4=0, K5=0
NSF-aware route hold timer is 240
Router-ID: 10.1.1.1
Topology : 0 (base)
Active Timer: 3 min
Distance: internal 90 external 170
Maximum path: 4
Maximum hopcount 100
Maximum metric variance 1
Automatic Summarization: disabled
Automatic address summarization:
Maximum path: 4
Routing for Networks:
10.0.0.0
Routing Information Sources:
Gateway Distance Last Update
10.1.2.2 90 200105
10.1.3.2 90 200113
10.1.4.2 90 254351
10.1.5.2 90 303742
Distance: internal 90 external 170
Corp#
show ip
protocols
(continued)
Routing Protocol is "rip"
Sending updates every 30 seconds, next due in 6 seconds
Invalid after 180 seconds, hold down 180, flushed after 240
Outgoing update filter list for all interfaces is not set
Incoming update filter list for all interfaces is not set
Redistributing: rip
Default version control: send version 2, receive 2
Interface Send Recv Triggered RIP Key-chain
Vlan1 2 2
FastEthernet0/0 2 2
Serial0/1/0 2 2
Serial0/0/1 2 2
Serial0/0/0 2 2
Automatic network summarization is not in effect
Maximum path: 4
Routing for Networks:
10.0.0.0
Passive Interface(s):
Routing Information Sources:
Gateway Distance Last Update
10.1.5.2 120 00:00:15
10.1.3.2 120 00:00:01
10.1.2.2 120 00:00:01
10.1.4.2 120 00:00:17
Distance: (default is 120)
Corp#
show ip
route
entire routing table
Codes: L - local, C - connected, S - static, R - RIP, M - mobile, B - BGP
D - EIGRP, EX - EIGRP external, O - OSPF, IA - OSPF inter area
N1 - OSPF NSSA external type 1, N2 - OSPF NSSA external type 2
E1 - OSPF external type 1, E2 - OSPF external type 2, E - EGP
i - IS-IS, L1 - IS-IS level-1, L2 - IS-IS level-2, ia - IS-IS inter area
* - candidate default, U - per-user static route, o - ODR
P - periodic downloaded static route
Gateway of last resort is not set
10.0.0.0/8 is variably subnetted, 10 subnets, 2 masks
C 10.1.1.0/24 is directly connected, Vlan1
L 10.1.1.1/32 is directly connected, Vlan1
C 10.1.2.0/24 is directly connected, Serial0/0/0
L 10.1.2.1/32 is directly connected, Serial0/0/0
C 10.1.3.0/24 is directly connected, Serial0/0/1
L 10.1.3.1/32 is directly connected, Serial0/0/1
C 10.1.4.0/24 is directly connected, Serial0/1/0
L 10.1.4.1/32 is directly connected, Serial0/1/0
C 10.1.5.0/24 is directly connected, FastEthernet0/0
L 10.1.5.1/32 is directly connected, FastEthernet0/0
172.16.0.0/16 is variably subnetted, 2 subnets, 2 masks
R 172.16.0.0/16 [120/1] via 10.1.5.2, 00:00:14, FastEthernet0/0
D 172.16.10.0/24 [90/28160] via 10.1.5.2, 00:07:23, FastEthernet0/0
D 192.168.10.0/24 [90/2172416] via 10.1.3.2, 00:09:13, Serial0/0/1
[90/2172416] via 10.1.2.2, 00:09:13, Serial0/0/0
D 192.168.20.0/24 [90/2172416] via 10.1.3.2, 00:09:13, Serial0/0/1
[90/2172416] via 10.1.2.2, 00:09:13, Serial0/0/0
D 192.168.30.0/24 [90/2172416] via 10.1.4.2, 00:08:59, Serial0/1/0
D 192.168.40.0/24 [90/2172416] via 10.1.4.2, 00:08:59, Serial0/1/0
Shows the entire routing table
Corp#
show ip
eigrp toplogy
all nets the Corp router can see, including on the other side of other routers
IP-EIGRP Topology Table for AS 10/ID(10.1.5.1)
Codes: P - Passive, A - Active, U - Update, Q - Query, R - Reply,
r - Reply status
directly connected via local egress interface
P 10.1.1.0/24, 1 successors, FD is 25625600
via Connected, Vlan1
P 10.1.2.0/24, 1 successors, FD is 2169856
via Connected, Serial0/0/0
P 10.1.3.0/24, 1 successors, FD is 2169856
via Connected, Serial0/0/1
P 10.1.4.0/24, 1 successors, FD is 2169856
via Connected, Serial0/1/0
P 10.1.5.0/24, 1 successors, FD is 28160
via Connected, FastEthernet0/0
remotely connected via remote ingress ip address
P 172.16.10.0/24, 1 successors, FD is 28160
via 10.1.5.2 (28160/25600), FastEthernet0/0
P 192.168.10.0/24, 2 successors, FD is 2172416
via 10.1.3.2 (2172416/28160), Serial0/0/1
via 10.1.2.2 (2172416/28160), Serial0/0/0
P 192.168.20.0/24, 2 successors, FD is 2172416
via 10.1.3.2 (2172416/28160), Serial0/0/1
via 10.1.2.2 (2172416/28160), Serial0/0/0
P 192.168.30.0/24, 1 successors, FD is 2172416
via 10.1.4.2 (2172416/28160), Serial0/1/0
P 192.168.40.0/24, 1 successors, FD is 2172416
via 10.1.4.2 (2172416/28160), Serial0/1/0
Corp#
show ip
eigrp interfaces
local interfaces on Corp, with peer data, 5 total, including VLAN1 (0 peers, no router on this network)
IP-EIGRP interfaces for process 10
Xmit Queue Mean Pacing Time Multicast Pending
Interface Peers Un/Reliable SRTT Un/Reliable Flow Timer Routes
Vlan 0 0/0 1236 0/10 0 0
Fa0/0 1 0/0 1236 0/10 0 0
Se0/0/1 1 0/0 1236 0/10 0 0
Se0/1/0 1 0/0 1236 0/10 0 0
Se0/0/0 1 0/0 1236 0/10 0 0
Corp#
show ip
eigrp neighbors
remote interfaces on the 4 neighboring routers
IP-EIGRP neighbors for process 10
H Address Interface Hold Uptime SRTT RTO Q Seq
(sec) (ms) Cnt Num
0 10.1.2.2 Se0/0/0 14 00:54:33 40 1000 0 58
1 10.1.3.2 Se0/0/1 10 00:54:33 40 1000 0 57
2 10.1.4.2 Se0/1/0 14 00:53:38 40 1000 0 51
3 10.1.5.2 Fa0/0 11 00:52:49 40 1000 0 33
4. Compare OSPF and RIPv1
RIPv1 is distance-vector and supports only classful routing. No VLSM
OSPF is link-state and supports VLSM and classless routing
5. Know how OSPF routers become neighboars and/or adjacent
they become neighbors when they see eachother's hello packets.
area id must match, links must be on the same subnet, hello/dead timers must be the same.
OSPF only shares routes with neigbors who have also established adjacencies. NOT ALL NEIGHBORS become adjacent.
When an OSPF router first receives a hello packet, it verifies that the data in some fields matches its own locally configured information.
Should any of the checked data be different, the hello packet is discarded and not processed. The data fields verified are the Area ID,
Authentication, Network Mask (on broadcast networks), Hello Interval, Router Dead Interval, and Options fields. If this information doesn’t match,
then neighborship is stuck in the down stage.
packetpushers.net
6. Be able to configure single-area OSPF
two commands:
router ospf [process id]
network x.x.x.x y.y.y.y area z
7. Be able to verify the operation of OSPF
Corp#
show ip
protocols
Corp#
show ip
route
Corp#
show ip
ospf
Corp#
show ip
ospf database
Corp#
show ip
ospf interface
Corp#
show ip
ospf neighbor
IOS 15.1
Corp#
show ip
protocols
Routing Protocol is "ospf 132"
Outgoing update filter list for all interfaces is not set
Incoming update filter list for all interfaces is not set
Router ID 10.1.5.1
Number of areas in this router is 1. 1 normal 0 stub 0 nssa
Maximum path: 4
Routing for Networks:
10.1.0.0 0.0.255.255 area 0
Routing Information Sources:
Gateway Distance Last Update
10.1.5.1 110 00:08:51
172.16.10.1 110 00:08:51
192.168.20.1 110 00:12:53
192.168.40.1 110 00:09:35
Distance: (default is 110)
IOS 15.1
Corp#
show ip
route
10.0.0.0/8 is variably subnetted, 10 subnets, 2 masks
C 10.1.1.0/24 is directly connected, Vlan1
L 10.1.1.1/32 is directly connected, Vlan1
C 10.1.2.0/24 is directly connected, Serial0/0/0
L 10.1.2.1/32 is directly connected, Serial0/0/0
C 10.1.3.0/24 is directly connected, Serial0/0/1
L 10.1.3.1/32 is directly connected, Serial0/0/1
C 10.1.4.0/24 is directly connected, Serial0/1/0
L 10.1.4.1/32 is directly connected, Serial0/1/0
C 10.1.5.0/24 is directly connected, FastEthernet0/0
L 10.1.5.1/32 is directly connected, FastEthernet0/0
172.16.0.0/24 is subnetted, 1 subnets
O 172.16.10.0/24 [110/10] via 10.1.5.2, 00:09:09, FastEthernet0/0
O 192.168.10.0/24 [110/65] via 10.1.2.2, 00:13:11, Serial0/0/0
O 192.168.20.0/24 [110/65] via 10.1.2.2, 00:13:01, Serial0/0/0
O 192.168.30.0/24 [110/65] via 10.1.4.2, 00:09:54, Serial0/1/0
O 192.168.40.0/24 [110/65] via 10.1.4.2, 00:09:54, Serial0/1/0
IOS 15.1
Corp#
show ip
ospf
Routing Process "ospf 132" with ID 10.1.5.1
Supports only single TOS(TOS0) routes
Supports opaque LSA
SPF schedule delay 5 secs, Hold time between two SPFs 10 secs
Minimum LSA interval 5 secs. Minimum LSA arrival 1 secs
Number of external LSA 0. Checksum Sum 0x000000
Number of opaque AS LSA 0. Checksum Sum 0x000000
Number of DCbitless external and opaque AS LSA 0
Number of DoNotAge external and opaque AS LSA 0
Number of areas in this router is 1. 1 normal 0 stub 0 nssa
External flood list length 0
Area BACKBONE(0)
Number of interfaces in this area is 5
Area has no authentication
SPF algorithm executed 7 times
Area ranges are
Number of LSA 5. Checksum Sum 0x034486
Number of opaque link LSA 0. Checksum Sum 0x000000
Number of DCbitless LSA 0
Number of indication LSA 0
Number of DoNotAge LSA 0
Flood list length 0
IOS 15.1
Corp#
show ip
ospf database
OSPF Router with ID (10.1.5.1) (Process ID 132)
Router Link States (Area 0)
Link ID ADV Router Age Seq# Checksum Link count
192.168.20.1 192.168.20.1 854 0x80000006 0x00ae08 6
192.168.40.1 192.168.40.1 656 0x80000004 0x006bc6 4
10.1.5.1 10.1.5.1 612 0x8000000f 0x00ab77 8
172.16.10.1 172.16.10.1 612 0x80000003 0x00b30d 2
Net Link States (Area 0)
Link ID ADV Router Age Seq# Checksum
10.1.5.1 10.1.5.1 612 0x80000001 0x00cc34
ADV Router aka RID/Router ID, the highest IP address on the router
we are seeing three connected routers + our own router (Corp at 10.1.5.1)
IOS 15.1
Corp#
show ip
ospf interface
Vlan1 is up, line protocol is up
Internet address is 10.1.1.1/24, Area 0
Process ID 132, Router ID 10.1.5.1, Network Type BROADCAST, Cost: 1
Transmit Delay is 1 sec, State DR, Priority 1
Designated Router (ID) 10.1.5.1, Interface address 10.1.1.1
No backup designated router on this network
Timer intervals configured, Hello 10, Dead 40, Wait 40, Retransmit 5
Hello due in 00:00:08
Index 1/1, flood queue length 0
Next 0x0(0)/0x0(0)
Last flood scan length is 1, maximum is 1
Last flood scan time is 0 msec, maximum is 0 msec
Neighbor Count is 0, Adjacent neighbor count is 0
Suppress hello for 0 neighbor(s)
FastEthernet0/0 is up, line protocol is up
Internet address is 10.1.5.1/24, Area 0
Process ID 132, Router ID 10.1.5.1, Network Type BROADCAST, Cost: 1
Transmit Delay is 1 sec, State DR, Priority 1
Designated Router (ID) 10.1.5.1, Interface address 10.1.5.1
Backup Designated Router (ID) 172.16.10.1, Interface address 10.1.5.2
Timer intervals configured, Hello 10, Dead 40, Wait 40, Retransmit 5
Hello due in 00:00:07
Index 2/2, flood queue length 0
Next 0x0(0)/0x0(0)
Last flood scan length is 1, maximum is 1
Last flood scan time is 0 msec, maximum is 0 msec
Neighbor Count is 1, Adjacent neighbor count is 1
Adjacent with neighbor 172.16.10.1 (Backup Designated Router)
Suppress hello for 0 neighbor(s)
Serial0/0/1 is up, line protocol is up
Internet address is 10.1.3.1/24, Area 0
Process ID 132, Router ID 10.1.5.1, Network Type POINT-TO-POINT, Cost: 64
Transmit Delay is 1 sec, State POINT-TO-POINT,
Timer intervals configured, Hello 10, Dead 40, Wait 40, Retransmit 5
Hello due in 00:00:07
Index 3/3, flood queue length 0
Next 0x0(0)/0x0(0)
Last flood scan length is 1, maximum is 1
Last flood scan time is 0 msec, maximum is 0 msec
Neighbor Count is 1 , Adjacent neighbor count is 1
Adjacent with neighbor 192.168.20.1
Suppress hello for 0 neighbor(s)
Serial0/1/0 is up, line protocol is up
Internet address is 10.1.4.1/24, Area 0
Process ID 132, Router ID 10.1.5.1, Network Type POINT-TO-POINT, Cost: 64
Transmit Delay is 1 sec, State POINT-TO-POINT,
Timer intervals configured, Hello 10, Dead 40, Wait 40, Retransmit 5
Hello due in 00:00:07
Index 4/4, flood queue length 0
Next 0x0(0)/0x0(0)
Last flood scan length is 1, maximum is 1
Last flood scan time is 0 msec, maximum is 0 msec
Neighbor Count is 1 , Adjacent neighbor count is 1
Adjacent with neighbor 192.168.40.1
Suppress hello for 0 neighbor(s)
Serial0/0/0 is up, line protocol is up
Internet address is 10.1.2.1/24, Area 0
Process ID 132, Router ID 10.1.5.1, Network Type POINT-TO-POINT, Cost: 64
Transmit Delay is 1 sec, State POINT-TO-POINT,
Timer intervals configured, Hello 10, Dead 40, Wait 40, Retransmit 5
Hello due in 00:00:07
Index 5/5, flood queue length 0
Next 0x0(0)/0x0(0)
Last flood scan length is 1, maximum is 1
Last flood scan time is 0 msec, maximum is 0 msec
Neighbor Count is 1 , Adjacent neighbor count is 1
Adjacent with neighbor 192.168.20.1
Suppress hello for 0 neighbor(s)
IOS 15.1
Corp#
show ip
ospf neighbor
Neighbor ID Pri State Dead Time Address Interface
192.168.20.1 0 FULL/ - 00:00:31 10.1.3.2 Serial0/0/1
192.168.40.1 0 FULL/ - 00:00:33 10.1.4.2 Serial0/1/0
192.168.20.1 0 FULL/ - 00:00:31 10.1.2.2 Serial0/0/0
172.16.10.1 1 FULL/BDR 00:00:32 10.1.5.2 FastEthernet0/0
Flashcards
Chapter 9 Written Lab 9.0
1. What four routed protocols are supported by EIGRP?
IPX, IPv4, IPv6, AppleTalk
2. When is redistribution required for EIGRP?
when there are multiple autonomous systems
redistribution is required when more than one EIGRP session or process is running and they are identified with different ASNs.
redistribution shares toplogy information between EIGRP sessions
3. What command would be used to enable EIGRP with an autonmous system number of 300?
router eigrp 300
4. What command will tell EIGRP that it is connected to network 172.10.0.0?
network 172.10.0.0
5. What type of EIGRP interface will neither send nor receive Hello packets?
passive-interface s0/0
6. Write the command that will enable OSPF process 101 on a router
router ospf 101
7. Write the command that will display details of all OSFP routing processes enabled on a router
show ip ospf
8. Write the command that will display interface-specific OSPF information
show ip ospf interface
9. Write the command that will display all OSPF neighbors
show ip ospf neighbor
10. Write the command that will display all different OSPF route types that are currently known by the router
show ip route ospf
Chapter 9 Hands-On Labs
Build the network and configure interfaces
LabA(config)#
int f0/0
LabA(config-if)#
ip addr 172.16.10.1 255.255.255.0
LabA(config-if)#
no shut
LabB(config)#
int f0/0
LabB(config-if)#
ip addr 172.16.10.2 255.255.255.0
LabB(config-if)#
no shut
LabB(config-if)#
int s0/0/0
LabB(config-if)#
ip addr 172.16.20.1 255.255.255.0
LabB(config-if)#
no shut
LabC(config)#
int f0/0
LabC(config-if)#
ip addr 172.16.30.1 255.255.255.0
LabC(config-if)#
no shut
LabC(config-if)#
int s0/0/0
LabC(config-if)#
ip addr 172.16.20.2 255.255.255.0
LabC(config-if)#
no shut
LabC(config-if)#
int s0/0/1
LabC(config-if)#
ip addr 172.16.40.1 255.255.255.0
LabC(config-if)#
no shut
LabD(config)#
int s0/0/0
LabD(config-if)#
ip addr 172.16.40.2 255.255.255.0
LabD(config-if)#
no shut
LabD(config-if)#
int f0/0
LabD(config-if)#
ip addr 172.16.50.1 255.255.255.0
LabD(config-if)#
no shut
9.1 - Configure and Verfiy EIGRP
configure EIGRP on all 4 routers and observe results
LabA
LabA(config)#
router eigrp 100
LabA(config-router)#
net 172.16.0.0
[no output]
LabA#
show ip eigrp neighbors
IP-EIGRP neighbors for process 100
LabA#
show ip eigrp topology
IP-EIGRP Topology Table for AS 100/ID(172.16.10.1)
Codes: P - Passive, A - Active, U - Update, Q - Query, R - Reply,
r - Reply status
P 172.16.10.0/24, 1 successors, FD is 28160
via Connected, FastEthernet0/0
LabA#
show ip eigrp interfaces
IP-EIGRP interfaces for process 100
Xmit Queue Mean Pacing Time Multicast Pending
Interface Peers Un/Reliable SRTT Un/Reliable Flow Timer Routes
Fa0/0 0 0/0 1236 0/10 0 0
no neighbors at this point since EIGRP is only active on this router. One successor AKA route, which is the connection out of this router.
But note that we have no information about what's on the other side of that link
LabB
LabB(config)#
router eigrp 100
LabB(config-router)#
net 172.16.0.0
%DUAL-5-NBRCHANGE: IP-EIGRP 100:
Neighbor 172.16.10.1 (FastEthernet0/0) is up: new adjacency
LabB#
show ip eigrp neighbors
IP-EIGRP neighbors for process 100
H Address Interface Hold Uptime SRTT RTO Q Seq
(sec) (ms) Cnt Num
0 172.16.10.1 Fa0/0 12 00:00:14 40 1000 0 1
LabB#
show ip eigrp topology
IP-EIGRP Topology Table for AS 100/ID(172.16.20.1)
Codes: P - Passive, A - Active, U - Update, Q - Query, R - Reply,
r - Reply status
P 172.16.10.0/24, 1 successors, FD is 28160
via Connected, FastEthernet0/0
P 172.16.20.0/24, 1 successors, FD is 2169856
via Connected, Serial0/0/0
LabB#
show ip eigrp interfaces
IP-EIGRP interfaces for process 100
Xmit Queue Mean Pacing Time Multicast Pending
Interface Peers Un/Reliable SRTT Un/Reliable Flow Timer Routes
Fa0/0 1 0/0 1236 0/10 0 0
Se0/0/0 0 0/0 1236 0/10 0 0
We can see a neighbor at .1
We now have two paths out of this router. Left to neighbor. Exit at right is available as successor(route), but again we have no info about
what is on the other side, since that router has no EIGRP yet (s0/0/0 has no peers, but is an EIGRP interface)
LabC
LabC(config)#
router eigrp 100
LabC(config-router)#
net 172.16.0.0
%DUAL-5-NBRCHANGE: IP-EIGRP 100:
Neighbor 172.16.20.1 (Serial0/0/0) is up: new adjacency
LabC#
show ip eigrp neighbors
IP-EIGRP neighbors for process 100
H Address Interface Hold Uptime SRTT RTO Q Seq
(sec) (ms) Cnt Num
0 172.16.20.1 Se0/0/0 12 00:00:25 40 1000 0 8
LabC#
show ip eigrp toplogy
IP-EIGRP Topology Table for AS 100/ID(172.16.40.1)
Codes: P - Passive, A - Active, U - Update, Q - Query, R - Reply,
r - Reply status
P 172.16.10.0/24, 1 successors, FD is 2172416
via 172.16.20.1 (2172416/28160), Serial0/0/0
P 172.16.20.0/24, 1 successors, FD is 2169856
via Connected, Serial0/0/0
P 172.16.30.0/24, 1 successors, FD is 28160
via Connected, FastEthernet0/0
P 172.16.40.0/24, 1 successors, FD is 2169856
via Connected, Serial0/0/1
LabC#
show ip eigrp interfaces
IP-EIGRP interfaces for process 100
Xmit Queue Mean Pacing Time Multicast Pending
Interface Peers Un/Reliable SRTT Un/Reliable Flow Timer Routes
Fa0/0 0 0/0 1236 0/10 0 0
Se0/0/0 1 0/0 1236 0/10 0 0
Se0/0/1 0 0/0 1236 0/10 0 0
.1 router B interface is now a neighbor.
LabC topology shows the 3 direct connected networks AND the network on the other side of LabB since LabB is our EIGRP neighbor
3 eigrp interfaces:
Fa0/0 is ours at LabC- no peers bc there is no eigrp router on the other end
s0/0/0 is our interface out left to LabB which is an EIGRP peer
s0/0/1 is our interface out right which does not see an EIGRP peer but does put that net 172.16.40.0 in our topology
LabD
LabD(config)#
router eigrp 100
LabD(config-router)#
net 172.16.0.0
%DUAL-5-NBRCHANGE: IP-EIGRP 100:
Neighbor 172.16.40.1 (Serial0/0/0) is up: new adjacency
LabD#
show ip eigrp neighbors
IP-EIGRP neighbors for process 100
H Address Interface Hold Uptime SRTT RTO Q Seq
(sec) (ms) Cnt Num
0 172.16.40.1 Se0/0/0 11 00:00:14 40 1000 0 6
LabD#
show ip eigrp topology
IP-EIGRP Topology Table for AS 100/ID(172.16.50.1)
Codes: P - Passive, A - Active, U - Update, Q - Query, R - Reply,
r - Reply status
P 172.16.10.0/24, 1 successors, FD is 2684416
via 172.16.40.1 (2684416/2172416), Serial0/0/0
P 172.16.20.0/24, 1 successors, FD is 2681856
via 172.16.40.1 (2681856/2169856), Serial0/0/0
P 172.16.30.0/24, 1 successors, FD is 2172416
via 172.16.40.1 (2172416/28160), Serial0/0/0
P 172.16.40.0/24, 1 successors, FD is 2169856
via Connected, Serial0/0/0
P 172.16.50.0/24, 1 successors, FD is 28160
via Connected, FastEthernet0/0
LabD#
show ip eigrp interfaces
IP-EIGRP interfaces for process 100
Xmit Queue Mean Pacing Time Multicast Pending
Interface Peers Un/Reliable SRTT Un/Reliable Flow Timer Routes
Fa0/0 0 0/0 1236 0/10 0 0
Se0/0/0 1 0/0 1236 0/10 0 0
LabC to our left is now a neighbor at 172.16.40.1
toplogy shows a route out to the right (no router on that end)
a route to the left to LabC .40.0
the .10.0, .20.0, and .30.0 networks via info from LabC
2 eigrp interfaces-
fa0/0 out to the right
s0/0/0 out left to LabC
Time to remove EIGRP from all four routers to prepare for the OSPF lab next,
since EIGRP has a lower AD than OSPF
LabA(config)#
no router eigrp 100
LabB(config)#
no router eigrp 100
LabC(config)#
no router eigrp 100
LabD(config)#
no router eigrp 100
9.2 - Enabling the OSPF Process
9.3 - Configuring OSPF Interfaces
9.4 - Verifying OSPF Operation
LabA
LabA(config)#
router ospf 100
LabA(config-router)#
net 172.16.10.1 0.0.0.0 area 0
[no output]
LabA#
show ip ospf neighbor
[no output]
LabA#
show ip ospf database
OSPF Router with ID (172.16.10.1) (Process ID 100)
Router Link States (Area 0)
Link ID ADV Router Age Seq# Checksum Link count
172.16.10.1 172.16.10.1 44 0x80000001 0x00b24b 1
LabA#
show ip ospf interface
FastEthernet0/0 is up, line protocol is up
Internet address is 172.16.10.1/24, Area 0
Process ID 100, Router ID 172.16.10.1, Network Type BROADCAST, Cost: 1
Transmit Delay is 1 sec, State DR, Priority 1
Designated Router (ID) 172.16.10.1, Interface address 172.16.10.1
No backup designated router on this network
Timer intervals configured, Hello 10, Dead 40, Wait 40, Retransmit 5
Hello due in 00:00:08
Index 1/1, flood queue length 0
Next 0x0(0)/0x0(0)
Last flood scan length is 1, maximum is 1
Last flood scan time is 0 msec, maximum is 0 msec
Neighbor Count is 0, Adjacent neighbor count is 0
Suppress hello for 0 neighbor(s)
we're including this router's interface 172.16.10.1 in our ospf area 0
fa0/0 now registers as an ospf interface
the ospf database includes data about this link only.... LabA is counting itself(10.1) as ADVERTISTING router?
the designated router is .1 LabA
LabB
LabB(config)#
router ospf 101
LabB(config-router)#
net 172.16.10.2 0.0.0.0 area 0
LabB(config-router)#
net 172.16.20.1 0.0.0.0 area 0
01:26:36: %OSPF-5-ADJCHG: Process 101, Nbr 172.16.10.1
on FastEthernet0/0 from LOADING to FULL, Loading Done
LabB#
show ip ospf neighbor
Neighbor ID Pri State Dead Time Address Interface
172.16.10.1 1 FULL/DR 00:00:33 172.16.10.1
LabB#
show ip ospf database
OSPF Router with ID (172.16.20.1) (Process ID 101)
Router Link States (Area 0)
Link ID ADV Router Age Seq# Checksum Link count
172.16.10.1 172.16.10.1 145 0x80000002 0x0067cd 1
172.16.20.1 172.16.20.1 32 0x80000003 0x006e8f 2
Net Link States (Area 0)
Link ID ADV Router Age Seq# Checksum
172.16.10.1 172.16.10.1 145 0x80000001 0x00953d
LabB#
show ip ospf interface
FastEthernet0/0 is up, line protocol is up
Internet address is 172.16.10.2/24, Area 0
Process ID 101, Router ID 172.16.20.1, Network Type BROADCAST, Cost: 1
Transmit Delay is 1 sec, State BDR, Priority 1
Designated Router (ID) 172.16.10.1, Interface address 172.16.10.1
Backup Designated Router (ID) 172.16.20.1, Interface address 172.16.10.2
Timer intervals configured, Hello 10, Dead 40, Wait 40, Retransmit 5
Hello due in 00:00:03
Index 1/1, flood queue length 0
Next 0x0(0)/0x0(0)
Last flood scan length is 1, maximum is 1
Last flood scan time is 0 msec, maximum is 0 msec
Neighbor Count is 1, Adjacent neighbor count is 1
Adjacent with neighbor 172.16.10.1 (Designated Router)
Suppress hello for 0 neighbor(s)
Serial0/0/0 is up, line protocol is up
Internet address is 172.16.20.1/24, Area 0
Process ID 101, Router ID 172.16.20.1, Network Type POINT-TO-POINT, Cost: 64
Transmit Delay is 1 sec, State POINT-TO-POINT,
Timer intervals configured, Hello 10, Dead 40, Wait 40, Retransmit 5
Hello due in 00:00:04
Index 2/2, flood queue length 0
Next 0x0(0)/0x0(0)
Last flood scan length is 1, maximum is 1
Last flood scan time is 0 msec, maximum is 0 msec
Suppress hello for 0 neighbor(s)
We've include the two interfaces on this router in the OSPF area
and can now see Router A's interface 10.1 to the left as a neighbor in the area
the "OSPF Database" now shows two links 20.1(local) and 10.1(neighbor) as 'router link states'.
"ADV Router" means advertising router for the two links. The link address is used as the advertising router.
database shows "Net Link States" category with one entry- 172.16.10.1 which is the address of neighbor router to our left
we have two local OSPF interfaces- f0/0 and s0/0/0
LabC
LabC(config)#
router ospf 102
LabC(config-router)#
net 172.16.20.2 0.0.0.0 area 0
LabC(config-router)#
net 172.16.30.1 0.0.0.0 area 0
LabC(config-router)#
net 172.16.40.1 0.0.0.0 area 0
01:33:54: %OSPF-5-ADJCHG: Process 102, Nbr 172.16.20.1
on Serial0/0/0 from LOADING to FULL, Loading Done
LabC#
show ip ospf neighbor
Neighbor ID Pri State Dead Time Address Interface
172.16.20.1 0 FULL/ - 00:00:30 172.16.20.1 Serial0/0/0
LabC#
show ip ospf database
OSPF Router with ID (172.16.40.1) (Process ID 102)
Router Link States (Area 0)
Link ID ADV Router Age Seq# Checksum Link count
172.16.10.1 172.16.10.1 542 0x80000002 0x0067cd 1
172.16.20.1 172.16.20.1 90 0x80000004 0x00a551 3
172.16.40.1 172.16.40.1 37 0x80000004 0x00e47c 4
Net Link States (Area 0)
Link ID ADV Router Age Seq# Checksum
172.16.10.1 172.16.10.1 542 0x80000001 0x00953d
LabC#
show ip ospf interface
Serial0/0/0 is up, line protocol is up
Internet address is 172.16.20.2/24, Area 0
Process ID 102, Router ID 172.16.40.1, Network Type POINT-TO-POINT, Cost: 64
Transmit Delay is 1 sec, State POINT-TO-POINT,
Timer intervals configured, Hello 10, Dead 40, Wait 40, Retransmit 5
Hello due in 00:00:01
Index 1/1, flood queue length 0
Next 0x0(0)/0x0(0)
Last flood scan length is 1, maximum is 1
Last flood scan time is 0 msec, maximum is 0 msec
Neighbor Count is 1 , Adjacent neighbor count is 1
Adjacent with neighbor 172.16.20.1
Suppress hello for 0 neighbor(s)
FastEthernet0/0 is up, line protocol is up
Internet address is 172.16.30.1/24, Area 0
Process ID 102, Router ID 172.16.40.1, Network Type BROADCAST, Cost: 1
Transmit Delay is 1 sec, State DR, Priority 1
Designated Router (ID) 172.16.40.1, Interface address 172.16.30.1
No backup designated router on this network
Timer intervals configured, Hello 10, Dead 40, Wait 40, Retransmit 5
Hello due in 00:00:02
Index 2/2, flood queue length 0
Next 0x0(0)/0x0(0)
Last flood scan length is 1, maximum is 1
Last flood scan time is 0 msec, maximum is 0 msec
Neighbor Count is 0, Adjacent neighbor count is 0
Suppress hello for 0 neighbor(s)
Serial0/0/1 is up, line protocol is up
Internet address is 172.16.40.1/24, Area 0
Process ID 102, Router ID 172.16.40.1, Network Type POINT-TO-POINT, Cost: 64
Transmit Delay is 1 sec, State POINT-TO-POINT,
Timer intervals configured, Hello 10, Dead 40, Wait 40, Retransmit 5
Hello due in 00:00:08
Index 3/3, flood queue length 0
Next 0x0(0)/0x0(0)
Last flood scan length is 1, maximum is 1
Last flood scan time is 0 msec, maximum is 0 msec
Suppress hello for 0 neighbor(s)
we include the three nets conneted to labC in the area.. 20.0, 30.0, and 40.0
link to our left, 20.1 is visible as "Neighbor"
OSPF Database-
Router Link States are
10.1(Router A)
20.1(Router B)
40.1(Router C)(This router)
Net Link States
10.1(Router A)... why does only Router A show here?
Reference- router link state vs net link state
Router Link States are type 1 LSAs. It lists all the routers in the area and the number of interfaces. 40.1 has 4 interfaces
Net Link States are the multi-access networks (Type 2 LSAs). The ADV (advertising router) is the DR.
LabD
LabD(config)#
router ospf 103
LabD(config-router)#
net 172.16.40.2 0.0.0.0 area 0
LabD(config-router)#
net 172.16.50.1 0.0.0.0 area 0
01:37:11: %OSPF-5-ADJCHG: Process 103, Nbr 172.16.40.1
on Serial0/0/0 from LOADING to FULL, Loading Done
LabD#
show ip ospf neighbor
Neighbor ID Pri State Dead Time Address Interface
172.16.40.1 0 FULL/ - 00:00:32 172.16.40.1 Serial0/0/0
LabD#
show ip ospf database
OSPF Router with ID (172.16.50.1) (Process ID 103)
Router Link States (Area 0)
Link ID ADV Router Age Seq# Checksum Link count
172.16.10.1 172.16.10.1 785 0x80000002 0x0067cd 1
172.16.20.1 172.16.20.1 333 0x80000004 0x00a551 3
172.16.40.1 172.16.40.1 111 0x80000005 0x00013b 5
172.16.50.1 172.16.50.1 53 0x80000003 0x001023 3
Net Link States (Area 0)
Link ID ADV Router Age Seq# Checksum
172.16.10.1 172.16.10.1 785 0x80000001 0x00953d
LabD#
show ip ospf interface
Serial0/0/0 is up, line protocol is up
Internet address is 172.16.40.2/24, Area 0
Process ID 103, Router ID 172.16.50.1, Network Type POINT-TO-POINT, Cost: 64
Transmit Delay is 1 sec, State POINT-TO-POINT,
Timer intervals configured, Hello 10, Dead 40, Wait 40, Retransmit 5
Hello due in 00:00:01
Index 1/1, flood queue length 0
Next 0x0(0)/0x0(0)
Last flood scan length is 1, maximum is 1
Last flood scan time is 0 msec, maximum is 0 msec
Neighbor Count is 1 , Adjacent neighbor count is 1
Adjacent with neighbor 172.16.40.1
Suppress hello for 0 neighbor(s)
FastEthernet0/0 is up, line protocol is up
Internet address is 172.16.50.1/24, Area 0
Process ID 103, Router ID 172.16.50.1, Network Type BROADCAST, Cost: 1
Transmit Delay is 1 sec, State WAITING, Priority 1
No designated router on this network
No backup designated router on this network
Timer intervals configured, Hello 10, Dead 40, Wait 40, Retransmit 5
Hello due in 00:00:04
Index 2/2, flood queue length 0
Next 0x0(0)/0x0(0)
Last flood scan length is 1, maximum is 1
Last flood scan time is 0 msec, maximum is 0 msec
Neighbor Count is 0, Adjacent neighbor count is 0
Suppress hello for 0 neighbor(s)
observations
the OSPF databases now match across all 4 routers.
NOTE that this is a database of routers, identified by
router ID. It is not a topology that lists routers AND routes,
like in the "equivalent" eigrp command.show eigrp topology
----------------------------------------------------------------------------------
PAUSE- a tale of a misconfigured network
After a 9 month hiatus, I am reviewing this book and have made it back to Chapter 9. I'm studing this webpage, working thorough the OSPF configurations
described above, and I get stuck on the concept of "link count" under "Router Link States" found in the output of show ip ospf database
The structure of the notes above is helpful, because I was tracking the state of each router BEFORE i made changes to the subsquent router. But just to be sure,
today I decided to recreate the topology, then configure each router one at a time, noting the results as I went.
And I ran into some problems.
Here is the original topology:
And today's recreated toplogy:
After replicating the toplogy and programming the IP addresses on each router, I started on configurations, just like before:
LabA
LabA(config)#
router ospf 100
LabA(config-router)#
net 172.16.10.1 0.0.0.0 area 0
[no output]
LabA#
show ip ospf neighbor
[no output]
LabA#
show ip ospf database
OSPF Router with ID (172.16.10.1) (Process ID 100)
Router Link States (Area 0)
Link ID ADV Router Age Seq# Checksum Link count
172.16.10.1 172.16.10.1 44 0x80000001 0x00b24b 1
LabA#
show ip ospf interface
FastEthernet0/0 is up, line protocol is up
Internet address is 172.16.10.1/24, Area 0
Process ID 100, Router ID 172.16.10.1, Network Type BROADCAST, Cost: 1
Transmit Delay is 1 sec, State DR, Priority 1
Designated Router (ID) 172.16.10.1, Interface address 172.16.10.1
No backup designated router on this network
Timer intervals configured, Hello 10, Dead 40, Wait 40, Retransmit 5
Hello due in 00:00:08
Index 1/1, flood queue length 0
Next 0x0(0)/0x0(0)
Last flood scan length is 1, maximum is 1
Last flood scan time is 0 msec, maximum is 0 msec
Neighbor Count is 0, Adjacent neighbor count is 0
Suppress hello for 0 neighbor(s)
good so far.... On to LabB router
LabB
LabB(config)#
router ospf 101
LabB(config-router)#
net 172.16.10.2 0.0.0.0 area 0
LabB(config-router)#
net 172.16.20.1 0.0.0.0 area 0
01:26:36: %OSPF-5-ADJCHG: Process 101, Nbr 172.16.10.1
on FastEthernet0/0 from LOADING to FULL, Loading Done
LabB#
show ip ospf neighbor
Neighbor ID Pri State Dead Time Address Interface
172.16.10.1 1 FULL/DR 00:00:33 172.16.10.1
LabB#
show ip ospf database
OSPF Router with ID (172.16.20.1) (Process ID 101)
Router Link States (Area 0)
Link ID ADV Router Age Seq# Checksum Link count
172.16.10.1 172.16.10.1 145 0x80000002 0x0067cd 1
172.16.20.1 172.16.20.1 32 0x80000003 0x006e8f 2
Net Link States (Area 0)
Link ID ADV Router Age Seq# Checksum
172.16.10.1 172.16.10.1 145 0x80000001 0x00953d
LabB#
show ip ospf interface
FastEthernet0/0 is up, line protocol is up
Internet address is 172.16.10.2/24, Area 0
Process ID 101, Router ID 172.16.20.1, Network Type BROADCAST, Cost: 1
Transmit Delay is 1 sec, State BDR, Priority 1
Designated Router (ID) 172.16.10.1, Interface address 172.16.10.1
Backup Designated Router (ID) 172.16.20.1, Interface address 172.16.10.2
Timer intervals configured, Hello 10, Dead 40, Wait 40, Retransmit 5
Hello due in 00:00:03
Index 1/1, flood queue length 0
Next 0x0(0)/0x0(0)
Last flood scan length is 1, maximum is 1
Last flood scan time is 0 msec, maximum is 0 msec
Neighbor Count is 1, Adjacent neighbor count is 1
Adjacent with neighbor 172.16.10.1 (Designated Router)
Suppress hello for 0 neighbor(s)
Serial0/0/0 is up, line protocol is up
Internet address is 172.16.20.1/24, Area 0
Process ID 101, Router ID 172.16.20.1, Network Type POINT-TO-POINT, Cost: 64
Transmit Delay is 1 sec, State POINT-TO-POINT,
Timer intervals configured, Hello 10, Dead 40, Wait 40, Retransmit 5
Hello due in 00:00:04
Index 2/2, flood queue length 0
Next 0x0(0)/0x0(0)
Last flood scan length is 1, maximum is 1
Last flood scan time is 0 msec, maximum is 0 msec
Suppress hello for 0 neighbor(s)
still looks good; same as before.... On to LabC router
LabC
LabC(config)#
router ospf 102
LabC(config-router)#
net 172.16.20.2 0.0.0.0 area 0
LabC(config-router)#
net 172.16.30.1 0.0.0.0 area 0
LabC(config-router)#
net 172.16.40.1 0.0.0.0 area 0
01:33:54: %OSPF-5-ADJCHG: Process 102, Nbr 172.16.20.1
on Serial0/0/0 from LOADING to FULL, Loading Done
LabC#
show ip ospf neighbor
[no output]
And here is where I ran into trouble. The show ip ospf neighbor command returns nothing. How can
that be?
After awhile I realized it is due to a misconfiguration in the topology.
For Lab C, I programmed the interfaces as follows:
LabC(config)#
int f0/0
LabC(config-if)#
ip addr 172.16.30.1 255.255.255.0
LabC(config-if)#
no shut
LabC(config-if)#
int s0/0/0
LabC(config-if)#
ip addr 172.16.20.2 255.255.255.0
LabC(config-if)#
no shut
LabC(config-if)#
int s0/0/1
LabC(config-if)#
ip addr 172.16.40.1 255.255.255.0
LabC(config-if)#
no shut
and again here is the topology for that router:
but here is what it SHOULD HAVE looked like (as it did the first time I built it)
S0/0/0 and S0/0/1 are swapped. When I gave the IP 172.16.20.2 to s/0/0/0, thinking that was the interface on the left side
which faces Lab B, I was actually giving 172.16.20.2 to the right side, facing LabC (which has no OSPF configs yet.)
Since the left side got got the IP intended for the right side which was 172.16.40.1
the inverse also occured-
the right side got the IP intended for the left which was 172.16.20.2
LabC left side should have been
s0/0/0 with 20.2
and LabC right side should have been
s0/0/1 with 40.1
The correct IPs were mapped to the correct interfaces. But the mistake happened before I even programmed them.
When I made the connections from LabB to LabC and from LabD to LabC, I plugged then into the wrong ports.
Interestingly.. not only is this causing OSPF to not see B as a neighbor from C.. but B and C cannot ping eachother either.
@B the config is 172.16.20.1/24 @ S0/0/0
@C the config is 172.16.40.1/24 @ S/0/0/1
meaning they are not even on the same network! But the system is not throwing any errors or bringing it to my attention.
It just fails to connect.
To correct the issue, I simply deleted those two links and re-created them. Worth noting, I used the auto select cable here,
which does not ask which interface you want to use when attaching. Earlier I must have plugged the right side first, and
auto select plugged into 0/0/0.
This time I plugged into left side first.
Now LabC OSPF data is reading out correctly...
LabC
LabC(config)#
router ospf 102
LabC(config-router)#
net 172.16.20.2 0.0.0.0 area 0
LabC(config-router)#
net 172.16.30.1 0.0.0.0 area 0
LabC(config-router)#
net 172.16.40.1 0.0.0.0 area 0
01:33:54: %OSPF-5-ADJCHG: Process 102, Nbr 172.16.20.1
on Serial0/0/0 from LOADING to FULL, Loading Done
LabC#
show ip ospf neighbor
Neighbor ID Pri State Dead Time Address Interface
172.16.20.1 0 FULL/ - 00:00:30 172.16.20.1 Serial0/0/0
LabC#
show ip ospf database
OSPF Router with ID (172.16.40.1) (Process ID 102)
Router Link States (Area 0)
Link ID ADV Router Age Seq# Checksum Link count
172.16.10.1 172.16.10.1 542 0x80000002 0x0067cd 1
172.16.20.1 172.16.20.1 90 0x80000004 0x00a551 3
172.16.40.1 172.16.40.1 37 0x80000004 0x00e47c 4
Net Link States (Area 0)
Link ID ADV Router Age Seq# Checksum
172.16.10.1 172.16.10.1 542 0x80000001 0x00953d
LabC#
show ip ospf interface
Serial0/0/0 is up, line protocol is up
Internet address is 172.16.20.2/24, Area 0
Process ID 102, Router ID 172.16.40.1, Network Type POINT-TO-POINT, Cost: 64
Transmit Delay is 1 sec, State POINT-TO-POINT,
Timer intervals configured, Hello 10, Dead 40, Wait 40, Retransmit 5
Hello due in 00:00:01
Index 1/1, flood queue length 0
Next 0x0(0)/0x0(0)
Last flood scan length is 1, maximum is 1
Last flood scan time is 0 msec, maximum is 0 msec
Neighbor Count is 1 , Adjacent neighbor count is 1
Adjacent with neighbor 172.16.20.1
Suppress hello for 0 neighbor(s)
FastEthernet0/0 is up, line protocol is up
Internet address is 172.16.30.1/24, Area 0
Process ID 102, Router ID 172.16.40.1, Network Type BROADCAST, Cost: 1
Transmit Delay is 1 sec, State DR, Priority 1
Designated Router (ID) 172.16.40.1, Interface address 172.16.30.1
No backup designated router on this network
Timer intervals configured, Hello 10, Dead 40, Wait 40, Retransmit 5
Hello due in 00:00:02
Index 2/2, flood queue length 0
Next 0x0(0)/0x0(0)
Last flood scan length is 1, maximum is 1
Last flood scan time is 0 msec, maximum is 0 msec
Neighbor Count is 0, Adjacent neighbor count is 0
Suppress hello for 0 neighbor(s)
Serial0/0/1 is up, line protocol is up
Internet address is 172.16.40.1/24, Area 0
Process ID 102, Router ID 172.16.40.1, Network Type POINT-TO-POINT, Cost: 64
Transmit Delay is 1 sec, State POINT-TO-POINT,
Timer intervals configured, Hello 10, Dead 40, Wait 40, Retransmit 5
Hello due in 00:00:08
Index 3/3, flood queue length 0
Next 0x0(0)/0x0(0)
Last flood scan length is 1, maximum is 1
Last flood scan time is 0 msec, maximum is 0 msec
Suppress hello for 0 neighbor(s)
Which brings me to the original reason I re-created this topology... I was confused about the LINK COUNTS
here:
OSPF Router with ID (172.16.40.1) (Process ID 102)
Router Link States (Area 0)
Link ID ADV Router Age Seq# Checksum Link count
172.16.10.1 172.16.10.1 542 0x80000002 0x0067cd 1
172.16.20.1 172.16.20.1 90 0x80000004 0x00a551 3
172.16.40.1 172.16.40.1 37 0x80000004 0x00e47c 4
Net Link States (Area 0)
Link ID ADV Router Age Seq# Checksum
172.16.10.1 172.16.10.1 542 0x80000001 0x00953d
The steps of recreating the lab were helpful, but this link answered the question:
Here is the output of each router's command show ip ospf interface as they are
set up one at a time.
LabA - No OSPF at B, C, or D yet
show ip ospf database
OSPF Router with ID (172.16.10.1) (Process ID 100)
Router Link States (Area 0)
Link ID ADV Router Age Seq# Checksum Link count
172.16.10.1 172.16.10.1 44 0x80000001 0x00b24b 1
LabB - No OSPF at C or D yet
show ip ospf database
OSPF Router with ID (172.16.20.1) (Process ID 101)
Router Link States (Area 0)
Link ID ADV Router Age Seq# Checksum Link count
172.16.10.1 172.16.10.1 145 0x80000002 0x0067cd 1
172.16.20.1 172.16.20.1 32 0x80000003 0x006e8f 2
Net Link States (Area 0)
Link ID ADV Router Age Seq# Checksum
172.16.10.1 172.16.10.1 145 0x80000001 0x00953d
the 20.2 interface on this router has 2 ospf links.
The left-facing out to RA, a crossover cable
The right-facing out to RC, a serial cable.
If the solution I found is correct, why is this serial link not being counted twice? The solution (I think)
is revealed after the configuration of the next router...
LabC - No OSPF at D yet
show ip ospf database
OSPF Router with ID (172.16.40.1) (Process ID 102)
Router Link States (Area 0)
Link ID ADV Router Age Seq# Checksum Link count
172.16.10.1 172.16.10.1 542 0x80000002 0x0067cd 1
172.16.20.1 172.16.20.1 90 0x80000004 0x00a551 3
172.16.40.1 172.16.40.1 37 0x80000004 0x00e47c 4
Net Link States (Area 0)
Link ID ADV Router Age Seq# Checksum
172.16.10.1 172.16.10.1 542 0x80000001 0x00953d
NOW we can see that the 20.1 link, which is the right-facing interface on LabB.. aka the router ID..
has THREE OSPF links.
Nothing changed on the left side of B. But on the right side, we now have an active OSPF router at the
other end of the link. This leads me to believe that the forum post was correct that 'serial links are counted twice',
but, more specifically, BOTH ENDS of the serial(PPP) link are counted... IF there is an OSPF router on each end.
This is backed up by the fact that LabC, OSPF id 40.1, has four OSPF links. The top-facing link to the 30
network DOES count.. even though it has no OSPF router on the other end. It counts because it's not a serial link.
The requirement of having an OSPF router on the other end for an interface to count here, only applies
to serial links. And pertains to BOTH ends of the link being counted.
In LabC's case, we have one serial at left, being counted twice. One ethernet at top, being counted once. And
one serial at right only being counted once because LabD is not active with OSPF yet.
If this is correct, then we should see Lab C's 40.1 count go to 5 after LabD is set for OSPF....
LabD - all 4 routers have OSPF
show ip ospf database
OSPF Router with ID (172.16.50.1) (Process ID 103)
Router Link States (Area 0)
Link ID ADV Router Age Seq# Checksum Link count
172.16.10.1 172.16.10.1 785 0x80000002 0x0067cd 1
172.16.20.1 172.16.20.1 333 0x80000004 0x00a551 3
172.16.40.1 172.16.40.1 111 0x80000005 0x00013b 5
172.16.50.1 172.16.50.1 53 0x80000003 0x001023 3
Net Link States (Area 0)
Link ID ADV Router Age Seq# Checksum
172.16.10.1 172.16.10.1 785 0x80000001 0x00953d
and back to LabC.....
show ip ospf database
OSPF Router with ID (172.16.40.1) (Process ID 102)
Router Link States (Area 0)
Link ID ADV Router Age Seq# Checksum Link count
172.16.10.1 172.16.10.1 1174 0x80000002 0x0067cd 1
172.16.20.1 172.16.20.1 722 0x80000004 0x00a551 3
172.16.40.1 172.16.40.1 500 0x80000005 0x00013b 5
172.16.50.1 172.16.50.1 441 0x80000003 0x001023 3
Net Link States (Area 0)
Link ID ADV Router Age Seq# Checksum
172.16.10.1 172.16.10.1 1174 0x80000001 0x00953d
Looks good! The link count for each router makes sense if you count the serial interfaces twice (one for each end).
the OSPF databases now match across all 4 routers.
NOTE that this is a database of routers, identified by
router ID. It is not a topology that lists routers AND routes, like in
the "equivalent" eigrp command show eigrp topology
Note that the .30 network is NOT represented here.
LabA#
show ip ospf database
OSPF Router with ID (172.16.10.1) (Process ID 100)
Router Link States (Area 0)
Link ID ADV Router Age Seq# Checksum Link count
172.16.10.1 172.16.10.1 1138 0x80000002 0x0067cd 1
172.16.20.1 172.16.20.1 686 0x80000004 0x00a551 3
172.16.40.1 172.16.40.1 463 0x80000005 0x00013b 5
172.16.50.1 172.16.50.1 404 0x80000003 0x001023 3
Net Link States (Area 0)
Link ID ADV Router Age Seq# Checksum
172.16.10.1 172.16.10.1 1138 0x80000001 0x00953d
LabB#
show ip ospf database
OSPF Router with ID (172.16.20.1) (Process ID 101)
Router Link States (Area 0)
Link ID ADV Router Age Seq# Checksum Link count
172.16.10.1 172.16.10.1 1151 0x80000002 0x0067cd 1
172.16.20.1 172.16.20.1 699 0x80000004 0x00a551 3
172.16.40.1 172.16.40.1 476 0x80000005 0x00013b 5
172.16.50.1 172.16.50.1 417 0x80000003 0x001023 3
Net Link States (Area 0)
Link ID ADV Router Age Seq# Checksum
172.16.10.1 172.16.10.1 1151 0x80000001 0x00953d
LabC#
show ip ospf database
OSPF Router with ID (172.16.40.1) (Process ID 102)
Router Link States (Area 0)
Link ID ADV Router Age Seq# Checksum Link count
172.16.10.1 172.16.10.1 1174 0x80000002 0x0067cd 1
172.16.20.1 172.16.20.1 722 0x80000004 0x00a551 3
172.16.40.1 172.16.40.1 500 0x80000005 0x00013b 5
172.16.50.1 172.16.50.1 441 0x80000003 0x001023 3
Net Link States (Area 0)
Link ID ADV Router Age Seq# Checksum
172.16.10.1 172.16.10.1 1174 0x80000001 0x00953d
LabD#
show ip ospf database
OSPF Router with ID (172.16.50.1) (Process ID 103)
Router Link States (Area 0)
Link ID ADV Router Age Seq# Checksum Link count
172.16.10.1 172.16.10.1 785 0x80000002 0x0067cd 1
172.16.20.1 172.16.20.1 333 0x80000004 0x00a551 3
172.16.40.1 172.16.40.1 111 0x80000005 0x00013b 5
172.16.50.1 172.16.50.1 53 0x80000003 0x001023 3
Net Link States (Area 0)
Link ID ADV Router Age Seq# Checksum
172.16.10.1 172.16.10.1 785 0x80000001 0x00953d
Below is our routing tables with OSPF data. We do see the .30 network here.
Everyone can reach it:
LabA via LabB's 10.2
LabB via LabC's 20.2
LabC via direct connection
LabD via LabC's 40.1
LabA#
show ip route
172.16.0.0/16 is variably subnetted, 6 subnets, 2 masks
C 172.16.10.0/24 is directly connected, FastEthernet0/0
L 172.16.10.1/32 is directly connected, FastEthernet0/0
O 172.16.20.0/24 [110/65] via 172.16.10.2, 00:28:03, FastEthernet0/0
O 172.16.30.0/24 [110/66] via 172.16.10.2, 00:21:35, FastEthernet0/0
O 172.16.40.0/24 [110/129] via 172.16.10.2, 00:21:25, FastEthernet0/0
O 172.16.50.0/24 [110/130] via 172.16.10.2, 00:17:40, FastEthernet0/0
LabB#
show ip route
172.16.0.0/16 is variably subnetted, 7 subnets, 2 masks
C 172.16.10.0/24 is directly connected, FastEthernet0/0
L 172.16.10.2/32 is directly connected, FastEthernet0/0
C 172.16.20.0/24 is directly connected, Serial0/0/0
L 172.16.20.1/32 is directly connected, Serial0/0/0
O 172.16.30.0/24 [110/65] via 172.16.20.2, 00:27:04, Serial0/0/0
O 172.16.40.0/24 [110/128] via 172.16.20.2, 00:26:54, Serial0/0/0
O 172.16.50.0/24 [110/129] via 172.16.20.2, 00:23:09, Serial0/0/0
LabC#
show ip route
172.16.0.0/16 is variably subnetted, 8 subnets, 2 masks
O 172.16.10.0/24 [110/65] via 172.16.20.1, 00:27:52, Serial0/0/0
C 172.16.20.0/24 is directly connected, Serial0/0/0
L 172.16.20.2/32 is directly connected, Serial0/0/0
C 172.16.30.0/24 is directly connected, FastEthernet0/0
L 172.16.30.1/32 is directly connected, FastEthernet0/0
C 172.16.40.0/24 is directly connected, Serial0/0/1
L 172.16.40.1/32 is directly connected, Serial0/0/1
O 172.16.50.0/24 [110/65] via 172.16.40.2, 00:23:36, Serial0/0/1
LabD#
show ip route
172.16.0.0/16 is variably subnetted, 7 subnets, 2 masks
O 172.16.10.0/24 [110/129] via 172.16.40.1, 00:25:20, Serial0/0/0
O 172.16.20.0/24 [110/128] via 172.16.40.1, 00:25:20, Serial0/0/0
O 172.16.30.0/24 [110/65] via 172.16.40.1, 00:25:20, Serial0/0/0
C 172.16.40.0/24 is directly connected, Serial0/0/0
L 172.16.40.2/32 is directly connected, Serial0/0/0
C 172.16.50.0/24 is directly connected, FastEthernet0/0
L 172.16.50.1/32 is directly connected, FastEthernet0/0
moving on.......
9.5 - OSPF DR and BDR Elections
EachRouter(config)#
hostname X (A, B, or C)
EachRouter(config)#
line con 0
EachRouter(config-line)#
exec-timeout 0 0
A(config)#
int f0/0
A(config-if)#
ip addr 10.1.1.1 255.255.255.0
A(config-if)#
no shut
A(config)#
router ospf 12345
A(config-router)#
net 10.1.1.0 0.0.0.255 area 0
00:23:30: %OSPF-5-ADJCHG: Process 12345, Nbr 10.1.1.3 on FastEthernet0/0 from LOADING to FULL, Loading Done
00:23:30: %OSPF-5-ADJCHG: Process 12345, Nbr 10.1.1.2 on FastEthernet0/0 from LOADING to FULL, Loading Done
A#
show ip ospf int
note this output was generated AFTER all 3 routers set for OSPF
FastEthernet0/0 is up, line protocol is up
Internet address is 10.1.1.1/24, Area 0
Process ID 12345, Router ID 10.1.1.1, Network Type BROADCAST, Cost: 1
Transmit Delay is 1 sec, State DROTHER, Priority 1
Designated Router (ID) 10.1.1.3, Interface address 10.1.1.3
Backup Designated Router (ID) 10.1.1.2, Interface address 10.1.1.2
Timer intervals configured, Hello 10, Dead 40, Wait 40, Retransmit 5
Hello due in 00:00:04
Index 1/1, flood queue length 0
Next 0x0(0)/0x0(0)
Last flood scan length is 1, maximum is 1
Last flood scan time is 0 msec, maximum is 0 msec
Neighbor Count is 2, Adjacent neighbor count is 2
Adjacent with neighbor 10.1.1.3 (Designated Router)
Adjacent with neighbor 10.1.1.2 (Backup Designated Router)
Suppress hello for 0 neighbor(s)
A(config-if)#shut
A(config-if)#
%LINK-5-CHANGED: Interface FastEthernet0/0, changed state to administratively down
%LINEPROTO-5-UPDOWN: Line protocol on Interface FastEthernet0/0, changed state to down
00:40:28: %OSPF-5-ADJCHG: Process 12345, Nbr 10.1.1.2 on FastEthernet0/0 from FULL to DOWN, Neighbor Down: Interface down or detached
00:40:28: OSPF: Build router LSA for area 0, router ID 10.1.1.1, seq 0xffffffff80000003
00:40:28: %OSPF-5-ADJCHG: Process 12345, Nbr 10.1.1.3 on FastEthernet0/0 from FULL to DOWN, Neighbor Down: Interface down or detached
00:40:28: OSPF: Build router LSA for area 0, router ID 10.1.1.1, seq 0xffffffff80000004
00:40:28: OSPF: Build router LSA for area 0, router ID 10.1.1.1, seq 0xffffffff80000004
A(config-if)#no shut
A(config-if)#
%LINK-5-CHANGED: Interface FastEthernet0/0, changed state to up
%LINEPROTO-5-UPDOWN: Line protocol on Interface FastEthernet0/0, changed state to up
00:40:48: OSPF: Build router LSA for area 0, router ID 10.1.1.1, seq 0xffffffff80000004
00:41:27: OSPF: Backup seen Event before WAIT timer on FastEthernet0/0
00:41:27: OSPF: DR/BDR election on FastEthernet0/0
00:41:27: OSPF: Elect BDR 10.1.1.2
00:41:27: OSPF: Elect DR 10.1.1.3
00:41:27: DR: 10.1.1.3 (Id) BDR: 10.1.1.2 (Id)
00:41:27: OSPF: Send DBD to 10.1.1.3 on FastEthernet0/0 seq 0x5accb8e2 opt 0x00 flag 0x7 len 32
B(config)#
int f0/0
B(config-if)#
ip addr 10.1.1.2 255.255.255.0
B(config-if)#
no shut
B(config)#
router ospf 12345
B(config-router)#
net 10.1.1.0 0.0.0.255 area 0
00:23:29: %OSPF-5-ADJCHG: Process 12345, Nbr 10.1.1.3 on FastEthernet0/0 from LOADING to FULL, Loading Done
00:23:29: %OSPF-5-ADJCHG: Process 12345, Nbr 10.1.1.1 on FastEthernet0/0 from LOADING to FULL, Loading Done
B#
show ip ospf int
note this output was generated AFTER all 3 routers set for OSPF
FastEthernet0/0 is up, line protocol is up
Internet address is 10.1.1.2/24, Area 0
Process ID 12345, Router ID 10.1.1.2, Network Type BROADCAST, Cost: 1
Transmit Delay is 1 sec, State BDR, Priority 1
Designated Router (ID) 10.1.1.3, Interface address 10.1.1.3
Backup Designated Router (ID) 10.1.1.2, Interface address 10.1.1.2
Timer intervals configured, Hello 10, Dead 40, Wait 40, Retransmit 5
Hello due in 00:00:05
Index 1/1, flood queue length 0
Next 0x0(0)/0x0(0)
Last flood scan length is 1, maximum is 1
Last flood scan time is 0 msec, maximum is 0 msec
Neighbor Count is 2, Adjacent neighbor count is 2
Adjacent with neighbor 10.1.1.1
Adjacent with neighbor 10.1.1.3 (Designated Router)
Suppress hello for 0 neighbor(s)
B#debug ip ospf adj
OSPF adjacency events debugging is on
B#
00:39:21: OSPF: DR/BDR election on FastEthernet0/0
00:39:21: OSPF: Elect BDR 10.1.1.2
00:39:21: OSPF: Elect DR 10.1.1.3
00:39:21: DR: 10.1.1.3 (Id) BDR: 10.1.1.2 (Id)
00:41:01: %OSPF-5-ADJCHG: Process 12345, Nbr 10.1.1.1 on FastEthernet0/0 from FULL to DOWN, Neighbor Down: Dead timer expired
00:41:01: %OSPF-5-ADJCHG: Process 12345, Nbr 10.1.1.1 on FastEthernet0/0 from FULL to DOWN, Neighbor Down: Interface down or detached
00:41:01: OSPF: Build router LSA for area 0, router ID 10.1.1.2, seq 0xffffffff80000003
00:41:01: OSPF: DR/BDR election on FastEthernet0/0
00:41:01: OSPF: Elect BDR 10.1.1.2
00:41:01: OSPF: Elect DR 10.1.1.3
C(config)#
int f0/0
C(config-if)#
ip addr 10.1.1.3 255.255.255.0
C(config-if)#
no shut
C(config)#
router ospf 12345
C(config-router)#
net 10.1.1.0 0.0.0.255 area 0
00:23:27: %OSPF-5-ADJCHG: Process 12345, Nbr 10.1.1.1 on FastEthernet0/0 from LOADING to FULL, Loading Done
00:23:27: %OSPF-5-ADJCHG: Process 12345, Nbr 10.1.1.2 on FastEthernet0/0 from LOADING to FULL, Loading Done
C#
show ip ospf int
note this output was generated AFTER all 3 routers set for OSPF
FastEthernet0/0 is up, line protocol is up
Internet address is 10.1.1.3/24, Area 0
Process ID 12345, Router ID 10.1.1.3, Network Type BROADCAST, Cost: 1
Transmit Delay is 1 sec, State DR, Priority 1
Designated Router (ID) 10.1.1.3, Interface address 10.1.1.3
Backup Designated Router (ID) 10.1.1.2, Interface address 10.1.1.2
Timer intervals configured, Hello 10, Dead 40, Wait 40, Retransmit 5
Hello due in 00:00:00
Index 1/1, flood queue length 0
Next 0x0(0)/0x0(0)
Last flood scan length is 1, maximum is 1
Last flood scan time is 0 msec, maximum is 0 msec
Neighbor Count is 2, Adjacent neighbor count is 2
Adjacent with neighbor 10.1.1.1
Adjacent with neighbor 10.1.1.2 (Backup Designated Router)
Suppress hello for 0 neighbor(s)
C#debug ip ospf adj
OSPF adjacency events debugging is on
C#
00:39:19: OSPF: DR/BDR election on FastEthernet0/0
00:39:19: OSPF: Elect BDR 10.1.1.2
00:39:19: OSPF: Elect DR 10.1.1.3
00:39:19: DR: 10.1.1.3 (Id) BDR: 10.1.1.2 (Id)
00:40:59: %OSPF-5-ADJCHG: Process 12345, Nbr 10.1.1.1 on FastEthernet0/0 from FULL to DOWN, Neighbor Down: Dead timer expired
00:40:59: %OSPF-5-ADJCHG: Process 12345, Nbr 10.1.1.1 on FastEthernet0/0 from FULL to DOWN, Neighbor Down: Interface down or detached
00:40:59: OSPF: Build router LSA for area 0, router ID 10.1.1.3, seq 0xffffffff80000003
00:40:59: OSPF: Build net LSA for area 0, router ID 10.1.1.3, seq 0xffffffff80000003
00:40:59: OSPF: DR/BDR election on FastEthernet0/0
00:40:59: OSPF: Elect BDR 10.1.1.2
00:40:59: OSPF: Elect DR 10.1.1.3
DR and BDR automtically set based on higest IP address
Note our network type is BROADCAST because we're using ethernet interfaces...
it would be point-to-point if using a serial connection
we want to manually overide the priority of the router. ZERO priority means it wont participate in the election process
MAX priority of 255 means no other router can beat it for DR
We'll set the priority for router A to 3.
It will beome the DR only after we shut/no shut the interface router
AND
manually power on/off the other two routers
A(config)#
int f0/0
A(config-int)#
ip ospf priority 3
A(config-int)#
shut
A(config-int)#
no shut
A#
debug ip ospf adj
B#
debug ip ospf adj
00:05:50: OSPF: DR/BDR election on FastEthernet0/0
00:05:50: OSPF: Elect BDR 10.1.1.2
00:05:50: OSPF: Elect DR 10.1.1.1
00:05:50: OSPF: Elect BDR 10.1.1.2
00:05:50: OSPF: Elect DR 10.1.1.1
00:05:50: DR: 10.1.1.1 (Id) BDR: 10.1.1.2 (Id)
00:05:50: OSPF: Send DBD to 10.1.1.1 on FastEthernet0/0 seq 0x10164ebb opt 0x00 flag 0x7 len 32
00:05:50: OSPF: Build router LSA for area 0, router ID 10.1.1.2, seq 0xffffffff80000002
00:05:52: OSPF: Rcv DBD from 10.1.1.1 on FastEthernet0/0 seq 0x20368093 opt 0x00 flag 0x7 len 32 mtu 1500 state EXSTART
00:05:52: OSPF: First DBD and we are not SLAVE
00:05:55: OSPF: Send DBD to 10.1.1.1 on FastEthernet0/0 seq 0x10164ebb opt 0x00 flag 0x7 len 32
00:05:55: OSPF: Rcv DBD from 10.1.1.1 on FastEthernet0/0 seq 0x10164ebb opt 0x00 flag 0x2 len 112 mtu 1500 state EXSTART
00:05:55: OSPF: NBR Negotiation Done. We are the MASTER
00:05:55: OSPF: Send DBD to 10.1.1.1 on FastEthernet0/0 seq 0x10164ebc opt 0x00 flag 0x3 len 52
00:05:55: OSPF: Rcv DBD from 10.1.1.1 on FastEthernet0/0 seq 0x10164ebc opt 0x00 flag 0x0 len 32 mtu 1500 state EXCHANGE
00:05:55: OSPF: Send DBD to 10.1.1.1 on FastEthernet0/0 seq 0x10164ebd opt 0x00 flag 0x1 len 32
00:05:55: OSPF: Rcv DBD from 10.1.1.1 on FastEthernet0/0 seq 0x10164ebd opt 0x00 flag 0x0 len 32 mtu 1500 state EXCHANGE
00:05:55: Exchange Done with 10.1.1.1 on FastEthernet0/0
00:05:55: OSPF: Database request to 10.1.1.1
00:05:55: OSPF: sent LS REQ packet to 10.1.1.1, length 36
00:05:55: OSPF: Rcv DBD from 10.1.1.1 on FastEthernet0/0 seq 0x10164ebd opt 0x00 flag 0x0 len 32 mtu 1500 state LOADING
00:05:55: Synchronized with with 10.1.1.1 on FastEthernet0/0, state FULL
00:05:55: %OSPF-5-ADJCHG: Process 12345, Nbr 10.1.1.1 on FastEthernet0/0 from LOADING to FULL, Loading Done
00:05:55: OSPF: Build router LSA for area 0, router ID 10.1.1.2, seq 0xffffffff80000002
C#
debug ip ospf adj
00:06:13: OSPF: DR/BDR election on FastEthernet0/0
00:06:13: OSPF: Elect BDR 10.1.1.2
00:06:13: OSPF: Elect DR 10.1.1.1
00:06:13: DR: 10.1.1.1 (Id) BDR: 10.1.1.2 (Id)
00:06:13: OSPF: Send DBD to 10.1.1.1 on FastEthernet0/0 seq 0x1cc5536d opt 0x00 flag 0x7 len 32
00:06:13: OSPF: Send DBD to 10.1.1.2 on FastEthernet0/0 seq 0x3d51ca66 opt 0x00 flag 0x7 len 32
00:06:13: OSPF: Build router LSA for area 0, router ID 10.1.1.3, seq 0xffffffff80000002
00:06:17: OSPF: Rcv DBD from 10.1.1.1 on FastEthernet0/0 seq 0x6b532eec opt 0x00 flag 0x7 len 32 mtu 1500 state EXSTART
00:06:17: OSPF: First DBD and we are not SLAVE
00:06:17: OSPF: Rcv DBD from 10.1.1.2 on FastEthernet0/0 seq 0x783110f4 opt 0x00 flag 0x7 len 32 mtu 1500 state EXSTART
00:06:17: OSPF: First DBD and we are not SLAVE
00:06:18: OSPF: Send DBD to 10.1.1.2 on FastEthernet0/0 seq 0x3d51ca66 opt 0x00 flag 0x7 len 32
00:06:18: OSPF: Send DBD to 10.1.1.1 on FastEthernet0/0 seq 0x1cc5536d opt 0x00 flag 0x7 len 32
00:06:18: OSPF: Rcv DBD from 10.1.1.2 on FastEthernet0/0 seq 0x3d51ca66 opt 0x00 flag 0x2 len 132 mtu 1500 state EXSTART
00:06:18: OSPF: NBR Negotiation Done. We are the MASTER
00:06:18: OSPF: Send DBD to 10.1.1.2 on FastEthernet0/0 seq 0x3d51ca67 opt 0x00 flag 0x3 len 52
00:06:18: OSPF: Rcv DBD from 10.1.1.1 on FastEthernet0/0 seq 0x1cc5536d opt 0x00 flag 0x2 len 132 mtu 1500 state EXSTART
00:06:18: OSPF: NBR Negotiation Done. We are the MASTER
00:06:18: OSPF: Send DBD to 10.1.1.1 on FastEthernet0/0 seq 0x1cc5536e opt 0x00 flag 0x3 len 52
00:06:18: OSPF: Rcv DBD from 10.1.1.2 on FastEthernet0/0 seq 0x3d51ca67 opt 0x00 flag 0x0 len 32 mtu 1500 state EXCHANGE
00:06:18: OSPF: Send DBD to 10.1.1.2 on FastEthernet0/0 seq 0x3d51ca68 opt 0x00 flag 0x1 len 32
00:06:18: OSPF: Rcv DBD from 10.1.1.1 on FastEthernet0/0 seq 0x1cc5536e opt 0x00 flag 0x0 len 32 mtu 1500 state EXCHANGE
00:06:18: OSPF: Send DBD to 10.1.1.1 on FastEthernet0/0 seq 0x1cc5536f opt 0x00 flag 0x1 len 32
00:06:18: OSPF: Rcv DBD from 10.1.1.2 on FastEthernet0/0 seq 0x3d51ca68 opt 0x00 flag 0x0 len 32 mtu 1500 state EXCHANGE
00:06:18: Exchange Done with 10.1.1.2 on FastEthernet0/0
00:06:18: OSPF: Database request to 10.1.1.2
00:06:18: OSPF: sent LS REQ packet to 10.1.1.2, length 48
00:06:18: OSPF: Rcv DBD from 10.1.1.1 on FastEthernet0/0 seq 0x1cc5536f opt 0x00 flag 0x0 len 32 mtu 1500 state EXCHANGE
verify on all three routers
A#
show ip ospf interface f0/0
FastEthernet0/0 is up, line protocol is up
Internet address is 10.1.1.1/24, Area 0
Process ID 12345, Router ID 10.1.1.1, Network Type BROADCAST, Cost: 1
Transmit Delay is 1 sec, State DR, Priority 3
Designated Router (ID) 10.1.1.1, Interface address 10.1.1.1
Backup Designated Router (ID) 10.1.1.2, Interface address 10.1.1.2
Timer intervals configured, Hello 10, Dead 40, Wait 40, Retransmit 5
Hello due in 00:00:09
Index 1/1, flood queue length 0
Next 0x0(0)/0x0(0)
Last flood scan length is 1, maximum is 1
Last flood scan time is 0 msec, maximum is 0 msec
Neighbor Count is 2, Adjacent neighbor count is 2
Adjacent with neighbor 10.1.1.2 (Backup Designated Router)
Adjacent with neighbor 10.1.1.3
Suppress hello for 0 neighbor(s)
A#
show ip ospf neighbor
Neighbor ID Pri State Dead Time Address Interface
10.1.1.2 1 FULL/BDR 00:00:37 10.1.1.2 FastEthernet0/0
10.1.1.3 1 FULL/DROTHER 00:00:30 10.1.1.3 FastEthernet0/0
B#
show ip ospf interface f0/0
FastEthernet0/0 is up, line protocol is up
Internet address is 10.1.1.2/24, Area 0
Process ID 12345, Router ID 10.1.1.2, Network Type BROADCAST, Cost: 1
Transmit Delay is 1 sec, State BDR, Priority 1
Designated Router (ID) 10.1.1.1, Interface address 10.1.1.1
Backup Designated Router (ID) 10.1.1.2, Interface address 10.1.1.2
Timer intervals configured, Hello 10, Dead 40, Wait 40, Retransmit 5
Hello due in 00:00:08
Index 1/1, flood queue length 0
Next 0x0(0)/0x0(0)
Last flood scan length is 1, maximum is 1
Last flood scan time is 0 msec, maximum is 0 msec
Neighbor Count is 2, Adjacent neighbor count is 2
Adjacent with neighbor 10.1.1.1 (Designated Router)
Adjacent with neighbor 10.1.1.3
Suppress hello for 0 neighbor(s)
B#
show ip ospf neighbor
Neighbor ID Pri State Dead Time Address Interface
10.1.1.1 3 FULL/DR 00:00:35 10.1.1.1 FastEthernet0/0
10.1.1.3 1 FULL/DROTHER 00:00:31 10.1.1.3 FastEthernet0/0
C#
show ip ospf interface f0/0
FastEthernet0/0 is up, line protocol is up
Internet address is 10.1.1.3/24, Area 0
Process ID 12345, Router ID 10.1.1.3, Network Type BROADCAST, Cost: 1
Transmit Delay is 1 sec, State DROTHER, Priority 1
Designated Router (ID) 10.1.1.1, Interface address 10.1.1.1
Backup Designated Router (ID) 10.1.1.2, Interface address 10.1.1.2
Timer intervals configured, Hello 10, Dead 40, Wait 40, Retransmit 5
Hello due in 00:00:06
Index 1/1, flood queue length 0
Next 0x0(0)/0x0(0)
Last flood scan length is 1, maximum is 1
Last flood scan time is 0 msec, maximum is 0 msec
Neighbor Count is 2, Adjacent neighbor count is 2
Adjacent with neighbor 10.1.1.1 (Designated Router)
Adjacent with neighbor 10.1.1.2 (Backup Designated Router)
Suppress hello for 0 neighbor(s)
C#
show ip ospf neighbor/span>
Neighbor ID Pri State Dead Time Address Interface
10.1.1.1 3 FULL/DR 00:00:35 10.1.1.1 FastEthernet0/0
10.1.1.2 1 FULL/BDR 00:00:37 10.1.1.2 FastEthernet0/0
Router1 is the DR with priority 3
still need more work to understand the output of the defbu ospf adj
Chapter 9 Review Questions
1. There are three possible routes for a router to reach a destination network:
OSPF with a metric of 782
RIPv2 with a metric of 4
EIGRP with a composite metric of 20514560
Which route will be installed in the routing table?
EIGRP because it has the lowest Administrative Distance, and AD is always used before metric
ADs are:
ExternalEIGRP 170
RIP 120
OSPF 110
IGRP 100
EIGRP 90
Static 1
Connected 0
2. Which EIGRP information is held in RAM and maintained through the use of Hello and update packets?
Neighbor table
and
toplogy table
3. Describe the process identifier that is used to run OSPF on a router
The OSPF process id is only locally significant. A random number can be selected. But it's required in order to identify
a unique OSPF database instance. You can use the same, or a different number on each router, doesnt matter.
Any number can be used from 1 to 65,535. Process ID is supplied as an argument to the command router ospf
NOT to be confused with the area number which can be any number up to 4 billion. The area id identifies a logical grouping of routers.
area id is supplied as argument to the OSPF network id and mask command
Ex:
R1(config)#
router ospf 12345
R1(config-router)#
net 10.1.1.0 0.0.0.255 area 0
4. Where are EIGRP successor routes stored?
EIGRP succesor routers are stored in the routing table. The "succesor" is the successful or primary route.
The successor route is ALSO listed in the topology table,
The feasible successor is a BACKUP route and will ONLY be listed in the topology table, unless the successor route fails,
in which case the feasible successor would become the successor
Note that my EIGRP setup doesnt seem to folow this.
CTRL-F jump to "remotely connected via remote ingress ip address"
the book states that EIGRP is automatically load-balancing our two links from R1 to corp.. is this why there is no feasible successor here?
I did some research and found that in our case, we are not using a Feasible Successor. You CAN have two Successors with equal metric, in which case EIGRP will
automatically load-balance.
But I wanted to find out what a Feasible Successor actually looks like in the EIGRP topology table..
Kevin Wallace EIGRP article
Conclusion:
EIGRP topology table wouldnt specifically say "Feasible Successor", but you would know by two routes appearing, one with a lower metric.
In my topology we have two equal-metric links and they are both considered "Successors". EIGRP uses them equally (load-balanced)
Corp#
show ip eigrp toplogy
[cut]
P 172.16.10.0/24, 1 successors, FD is 28160
via 10.1.5.2 (28160/25600), FastEthernet0/0
P 192.168.10.0/24, 2 successors, FD is 2172416
via 10.1.3.2 (2172416/28160), Serial0/0/1
via 10.1.2.2 (2172416/28160), Serial0/0/0
P 192.168.20.0/24, 2 successors, FD is 2172416
via 10.1.3.2 (2172416/28160), Serial0/0/1
via 10.1.2.2 (2172416/28160), Serial0/0/0
P 192.168.30.0/24, 1 successors, FD is 2172416
via 10.1.4.2 (2172416/28160), Serial0/1/0
P 192.168.40.0/24, 1 successors, FD is 2172416
via 10.1.4.2 (2172416/28160), Serial0/1/0
5. Which command will display all the EIGRP feasible successor routes to a known router.
show ip eigrp topology
6. Find the configuration error. You type the following into your router, but dont see any routes in the routing table?
Router(config)#
router ospf 1
Router(config-router)#
network 10.0.0.0 255.0.0.0
wrong wildcard mask
instead, could have used
0.255.255.255
or
0.0.0.255
the point is we need to specify the first octet as "allowed" into our OSPF config with a 0 mask.
The remaining bits are 'dont care' bits aka 'wildcard' aka 255
7. Which three protocols support VLSM, summarization, and discontigous networking?
RIPv2
EIGRP
OSPF
all 3 build and mainting routing tables, provide classless routing which allows VLSM, summarization, and discontigous networks
RIPv1 and IGRP build/maintain routing tables, but dont offer classless routing
8. Which are true regarding OSPF areas?
the 'backbone' is area 0
if using other areas, they all must directly connect to area 0
9. Which two network types have a designated router and a backup designated router?
Broadcast
NBMA- Non broadcast multi access. Ex: Frame Relay
network types that DO NOT use DR/BDR:
point to point
broadcast multipoint
10. You need to configure a router with a distance-vector protocol that allows classless routing. Which to use?
EIGRP is considered 'advanced distance vector' (ripv2 wasnt an option)
11. You need the IP address of the devices with which the router has established an adjacency.
Also, the retransmit interval and the queue counts for the adjacent routers need to be checked. What command will display the required information?
show ip eigrp neighbors
WRONG: show ip eigrp adjacency - there is no such command.. the word 'adjacency' is only used with debug ip OSPF adjacency
here are the possible commands for show ip eigrp and debug ip eigrp
show ip eigrp ?
interfaces IP-EIGRP interfaces
neighbors IP-EIGRP neighbors
topology IP-EIGRP Topology Table
traffic IP-EIGRP Traffic Statistics
debug ip eigrp ?
summary IP-EIGRP summary route processing
12. You cant establish an adjacency relationship on a common ethernet link between two routers. Based on the output below, what is the cause of the problem?
RouterA#
Ethernet0/0 is up, line protocol is up
Internet Address 172.16.1.2/16, Area 0
Process ID 2, Router ID 172.126.1.2, Network Type BROADCAST, Cost: 10
Transmit Delay is 1 sec, State DR, Priority 1
Designated Router (ID) 172.16.1.2, interface address 172.16.1.1.
No backup designated router on this network
Timer intervals configured, Hello 5, Dead 20, Wait 20, Retransmit 5
Router B#
Internet Address 172.16.1.1/16, Area 0
Process ID 2, Router ID 172.126.1.1, Network Type BROADCAST, Cost: 10
Transmit Delay is 1 sec, State DR, Priority 1
Designated Router (ID) 172.16.1.1, interface address 172.16.1.2.
No backup designated router on this network
Timer intervals configured, Hello 10, Dead 40, Wait 40, Retransmit 5
mismatched timer intervals
OSPF default Hello is 10 and Dead is 40... RouterA was modified
13. Which is true regarding EIGRP successor routes?
Used in the routing table
also appears in the topolgy table
may (or may not) have a backup feasabile successor
14. Which type of OSPF network will elect a backup designated router?
broadcast multi-access
non-broadcast multiaccess
types of network that will NOT elect a BDR:
point to point and brodacast multipoint (hub/spoke topology)
15. Which two commands will place network 10.2.3.0/24 into area 0?
Router(config)#
router ospf 10
Router(config-router)#
network 10.2.3.0 0.0.0.255 area 0
16. With which network type will OSPF establish router adjacencies but not perform the DR/BDR election process?
Point to point
no election process occurs, there is never a DR on point to point
17. What are three reasons for creating OSPF in a heirarchical design?
decrease routing overhead
speed up convergence
confine stability to single areas of the network
18. What is the administrative distance of OSPF?
110
19.
no auto summary
the network is considered discontigous because we have two classful network subnetted (on the left and right),
seperated by a different classful address.
if auto summarization is taking place, the routers cant determine which side is which because both sides would be summarized as
Class B, 172.16.0.0, which isnt specific enough to distinguish between the sides.
20. IF routers in a single area are configured with the same priority value, what value does a router use for the OSPF router ID in the absence of a loopback interface?
The highest IP of any PHSYICAL interface.
Trick question. Highest IP of any LOGICAL interface is an option. And is correct IF you had logical interfaces, but the question
states that any "logical interfaces are absent".
At OSPF startup, the highest IP of *any* active interface on the router becomes the OSPF router ID. If you have loopback (logical) interfaces configured,
one of them (the largest IP) will *override* the phsyical interfaces and the loopback IP becomes the RID.
Reference for which loopback (if multiple) wins:
packetpushers.net
------------------------------------------------------------------------------
END CHAPTER 9
41 hours 2-14 thru 2-28-22
original total 184 hours
14 hours review 12-26 thru 12-28-22
review total hours 46
book page 502/822
184 + 46 = 230 hours * 60 = (13,800 min) / 500 pages =
avg 28 min/page (includes reading and exercises/labs + online research)
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1. verify connection to the server
R1# ping 193.1.1.2
2. copy running-confing to server
R1# copy run tftp
R1# ping 193.1.1.2
Type escape sequence to abort.
Sending 5, 100-byte ICMP Echos to 193.1.1.4, timeout is 2 seconds:
!!!!!
Success rate is 100 percent (5/5), round-trip min/avg/max = 0/0/1 ms
2. copy running-confing to server
R1# copy run tftp
Address or name of remote host []? 193.1.1.4
Destination filename [R1-confg]?ENTER "R1-confg" is the default name
Writing running-config...!!
[OK - 668 bytes]
668 bytes copied in 0.004 secs (167000 bytes/sec)
R1# show cdp
Global CDP information:
Sending CDP packets every 60 seconds
Sending a holdtime value of 180 seconds
Sending CDPv2 advertisements is enabled
R1# show cdp interface
Vlan1 is administratively down, line protocol is down
Sending CDP packets every 60 seconds
Holdtime is 180 seconds
GigabitEthernet0/0/0 is up, line protocol is up
Sending CDP packets every 60 seconds
Holdtime is 180 seconds
GigabitEthernet0/0/1 is administratively down, line protocol is down
Sending CDP packets every 60 seconds
Holdtime is 180 seconds
GigabitEthernet0/0/2 is administratively down, line protocol is down
Sending CDP packets every 60 seconds
Holdtime is 180 seconds
R1# show cdp entry *
Device ID: SW1
Entry address(es):
Platform: cisco 2960, Capabilities: Switch
Interface: GigabitEthernet0/0/0, Port ID (outgoing port): FastEthernet0/1
NOTE g0/0/0 is the outgoing port on this router, F0/1 is the port on the switch at other end
Holdtime: 157
Version :
Cisco IOS Software, C2960 Software (C2960-LANBASEK9-M), Version 15.0(2)SE4, RELEASE SOFTWARE (fc1)
Technical Support: http://www.cisco.com/techsupport
Copyright (c) 1986-2013 by Cisco Systems, Inc.
Compiled Wed 26-Jun-13 02:49 by mnguyen
advertisement version: 2
Duplex: full
R1# show cdp entry neighbors
[no output]
R1# show cdp neighbors detail
Device ID: SW1
Entry address(es):
Platform: cisco 2960, Capabilities: Switch
Interface: GigabitEthernet0/0/0, Port ID (outgoing port): FastEthernet0/1
Holdtime: 178
Version :
Cisco IOS Software, C2960 Software (C2960-LANBASEK9-M), Version 15.0(2)SE4, RELEASE SOFTWARE (fc1)
Technical Support: http://www.cisco.com/techsupport
Copyright (c) 1986-2013 by Cisco Systems, Inc.
Compiled Wed 26-Jun-13 02:49 by mnguyen
advertisement version: 2
Duplex: full
Chapter 7 Hands-on Lab 7.5 Using Telnet
enable telnet on R2 and set password
R2(config)#
line vty 0 15
R2(config-line)#
password telnet
R2(config-line)#
login
enable telnet on R3 and set password
R3(config)#
line vty 0 15
R3(config-line)#
password telnet
R3(config-line)#
login
note that the result of this command on each router, by default,
is to present all 15 lines in TWO SEPERATE chunks: 0-4 and 5-15
R3#
show run
[cut]
!
!
!
line con 0
!
line aux 0
!
line vty 0 4
password telnet
login
line vty 5 15
password telnet
login
!
!
!
end
--------------------------------------------------------------------------------
connect to R2 from R1
R1#
telnet 193.1.1.2
Trying 193.1.1..2 ...Open
User Access Verification
Password: telnet
prompt changes to R2 to indicate we are remoted in
R2>
exit the session
ctrl + shift + 6, x
prompt changes back to R1
R1#
--------------------------------------------------------------------------------
connect to R3 from R1
R1#
193.1.1.3 note that the word 'telnet' is not required bc we are still in telnet mode
Trying 193.1.1..3 ...Open
User Access Verification
Password: telnet
prompt changes to R3 to indicate we are remoted in
R3>
exit the session
ctrl + shift + 6, x
prompt changes back to R1
R1#
--------------------------------------------------------------------------------
We have exited the sessions, but they are still open
R1#
show sessions
Conn Host Address Byte Idle Conn Name
1 193.1.1.2 193.1.1.2 0 0 193.1.1.2
* 2 193.1.1.3 193.1.1.3 0 0 193.1.1.3
two telnet sessions- notice that the 'conn number' doesnt correspond to ip address in any way.
R1#
show users
Line User Host(s) Idle Location
* 0 con 0 193.1.1.2 00:00:03
193.1.1.3 00:00:43
this is saying one user is on this router, with two outbound connections (but it isnt showing that they are vty connections)
... they must both be considered 'console' connections outbound and are not considered 'vty' until they are received inbound
the asterisk means something different here than above... doesnt mean default(most recent)session... what does it mean?
back to R2
R2#
show users
Line User Host(s) Idle Location
* 4 vty 0 idle 00:00:00 193.1.1.1
Interface User Mode Idle Peer Address
this is saying that there is one (unnamed) user remoted in via line vty 4
back to R3
R3#
show users
Line User Host(s) Idle Location
* 4 vty 0 idle 00:00:00 193.1.1.1
Interface User Mode Idle Peer Address
this is saying that there is one (unnamed) user remoted in via line vty 4
-------------------------------------------------------------------------------------
Important Considerations:
-
asterisk indicates default session
-
when telnetting in, you will be in user mode. If there is no password already set for PRIVILEGED MODE, you will be unable to enter
-
be careful with 'exit'. it will exit the telnet session if you exit at priv. mode. Use 'disable' to leave priv mode.
-
after 'suspending' a session with ctrl+shift+6,x and youre back at your original priv. prompt, do not press enter to create line breaks-
rather than break lines as usual, the keystroke will cause this:
[Resuming connection 1 to 193.1.1.2 ... ]
prompt will sit here until you strike enter again, then you'll return to that session. What is actually happening is that
youre connecting to the 'default' telnet connection. The same behavior happens when youre at the 'show sessions' screen.
Even if you are not viewing active sessions, the enter key(twice) will connect you to the default session
-
you can use disconnect or exit to end a session
-
Ex: disconnect 1 at the show sessions screen
Chapter 7 Hands-on Lab 7.6 Resolving Hostnames
We're going to build a host table on R1 so we can connect to the other routers via hostname rather than type in the IP address
the command is ip host name arg ip arg
R1(config)#
ip host R2 193.1.1.2
R1(config)#
ip host R3 193.1.1.3
Now if we enter R2 or telnet R2 we get the telnet prompt
R1# R2
Trying 193.1.1.2 ...Open
User Access Verification
Password:
same for the PING command
R1# ping R2
Type escape sequence to abort.
Sending 5, 100-byte ICMP Echos to 193.1.1.2, timeout is 2 seconds:
!!!!!
Success rate is 100 percent (5/5), round-trip min/avg/max = 0/0/2 ms
R1#
show hosts
Default Domain is not set
Name/address lookup uses domain service
Name servers are 255.255.255.255
Codes: UN - unknown, EX - expired, OK - OK, ?? - revalidate
temp - temporary, perm - permanent
NA - Not Applicable None - Not defined
Host Port Flags Age Type Address(es)
R2 None (perm, OK) 0 IP 193.1.1.2
R3 None (perm, OK) 0 IP 193.1.1.3
R1#
telnet R2
R2>
CTRL + SHIFT + 6, X
R1#
telnet R3
R3>
CTRL + SHIFT + 6, X
R1#
show session
Conn Host Address Byte Idle Conn Name
1 R2 193.1.1.2 0 0 R2
* 2 R3 193.1.1.3 0 0 R3
Chapter 7 Review Questions
1. What does the command
confreg 0x2142
provide?
bypass startup-config, to allow password reset
2. Which command will copy the IOS to a backup host on your network?
copy flash tftp
3. You are troubleshooting a connectivity problem in your corporate network and want to isolate the problem. You suspect that a router on the route to an unreachable
network is at fault. What IOS user exec command should you issue?
traceroute
note this is not a priviliged mode command; it can be run from user mode
4. You copy a configuration from a network host to a router's RAM. The configuration looks correct, yet it is no working at all. What could the problem be?
when you perform a copy from a network host to a router, the interfaces are automatically shut down and have to be manually enabled with no shutdown
5. A network administrator wants to upgrade the IOS of a router without removing the image currently installed. What command will display the amount of memory consumed by the
current IOS image and indicate whether there is enough room available to hold both the current and new images?
show flash
6. The corporate office sends you a new router to connect, but upon connecting the console cable, you see that there is already a configuration on the router.
What should be done before a new configuration is entered in the router?
erase NVRAM and restart the router
erase startup-config
reload
7. Which command loads a new version of the Cisco IOS into a router?
copy tftp flash
8. Which command will show you the IOS version running on your router?
show version
9. What should the configuration register value be after you successfully complete the password recovery procedure and return the router to normal operation?
0x2102
10. You save the configuration on a router with the
copy running-config startup-config
command and reboot the router. The router, however, comes up with a blank configuration. What can the problem be?
wrong config register causing you to bypass startup-confing in NVRAM
11. If you want to have more than one Telnet session open at the same time, what keystroke combination would you use?
CTRL+SHIFT+6, X
12. You are unsuccessful in telnetting into a remote device, but you could telnet to the router earlier, However, you can still ping the remote device.
What can the problem be?
access control list could be filtering telnet
OR
the VTY password may not be set on the target
13. What information is displayed by the
show hosts
command?
gives info on temporary DNS entries and permanent name-to-address mappings created using the ip host command
14. Name three commands that can be used to check LAN connectivity problems on a router?
trace
show interfaces
show ip route
15. You telnet to a router and make your necessary changes; now you want to end the Telnet session. What command do you type in?
exit
16. You telnet into a remote device and type
debug ip rip
but no output from the
debug
command is seen. What could the problem be?
to see console messages through a telnet session, you must enter the command terminal monitor
17. Which command displays the configuration register setting?
show version
18. You need to gather the IP address of a remote switch that is located in Hawaii. What can you do to find the address?
show cdp neighbors detail
19. You have your laptop directly connected into a router's Ethernet port. Which are requirements for the
copy flash tftp
command to be successful?
have a TFTP server running on the laptop
laptop must have an IP on the same subnet as the router interface
give the IP address of the laptop when asked after entering the command
20. The configuration register setting of 0x2102 provides what function to a router?
points to NVRAM for startup-configuration AND boot sequence
END CHAPTER 7
26 hours 1-19 thru 1-26-22
original total hours 89
7 hours review 12-23-22
review total hours 20.5
book page 344/822
avg 15 min/page (reading and exercises/labs)
Chapter 8 Exercises
pg 374
before I begin to configure this network, I want to look closer at the HARDWARE
Todd mentions these routers:
2811 with four serial interfaces and switch module or wireless card
1841
while the book was published in 2011, both routers appear to be available in 2021 packet tracer,
but both are considered legacy as of Feb 2022.
The 2811:
The 1841:
we're going to need to understand the MODULES. What are these?
a few examples:
NM-1E is a 1-port ethernet module
NM-1FE-TX is a fast ethernet module
NM-8A/s is an Eight Port Async/Sync Network Module
HWIC-2T is a 2-port serial WAN interface card
HWIC-AP-AG-B is a wireless card
What is an "NM module"?
A network module is a software module that implements a specific
function in a network stack, such as a data link interface, a transport protocol,
or a network application.
What is a "HWIC module"?
A high-speed WAN interface card
Here is a look inside a real 2811:
Back to the requirements for our lab- Todd says the 2811 'Corp' router needs a switch module
and four serial interfaces. NOTE the book doesnt give specifics on how to create the topology in Packet Tracer.
Our Packet Tracer 2811 offers these modules:
The NM-ESW-16 appears to be the only 'switch module', so I will add that.
And the HWIC-2T is a 2-Port Serial High-Speed WAN Interface Card, providing 2 serial ports.
I will add two of these.
next: R3, which needs to be a 2811 with a wirless card. I will add the HWIC-AP-AG-B:
The HWIC-AP-AG-B module is a High-Speed WAN Interface Card providing integrated Access Point
functionality in the Cisco 1800 (Modular), Cisco 2800,
and Cisco 3800 Integrated Services Routers.
It supports Single Band 802.11b/g or Dual Band 802.11a/b/g radios.
our router hardware is in place:
and here is where we need to end up
Next we need to figure out how to connect the server farm to the switch card on R1:
if I use the auto-select cable, I get a copper crossover cable connecting at fa0/0 on the router.
Per the diagram fa0/0 should
connect to R3. I need to connect the servers to the switch card on R1.
Instead of using the auto-select cable, I'll try a straight-through cable.
Success. While the auto-select cable did not give me an option as to what port it will connect to, I did get the option when
manually applying the straight-through cable. Instead of connecting to F0/0 which would require a crossover-cable(computer to router),
I will connect to the integrated switch at port F1/0, then connect the other two servers to F1/1 and F1/2, respectively.
Also worth noting: the Physical Device diagrams in Packet Tracer do not show cables plugged into the ports.
We are relying on the labels on the logical diagram to see which cables are plugged into which ports...
As far as how we can tell what is connected from within the CLI.. I dont know right now.
Now I will connect the other routers. Here is the chart specifiying what interfaces should be used:
Router
Network Address
Interface
Address
CORP
10.1.1.0
Vlan1 (switch card)
10.1.1.1
10.1.2.0
S0/0/0
10.1.2.1
10.1.3.0
S0/0/1 (DCE)
10.1.3.1
10.1.4.0
S0/1/0
10.1.4.1
10.1.5.0
F0/0
10.1.5.1
R1
10.1.2.0
S0/0/0 (DCE)
10.1.2.2
10.1.3.0
S0/0/1
10.1.3.2
192.168.10.0
F0/0
192.168.10.1
192.168.20.0
F0/1
192.168.20.1
R2
10.1.4.0
S0/0/0 (DCE)
10.1.4.2
192.168.30.0
F0/0
192.168.30.1
192.168.40.0
F0/0
192.168.40.1
R3
10.1.5.0
F0/0
10.1.5.2
172.16.10.0
Dot11Radio0/0/0
172.16.10.1
PROBLEM
The R1 router doesnt appear to have any serial interfaces
I will add an HWIC-2T card to both R1 and R2 since the diagram calls for serial interfaces.
The HWIC-2T is a Cisco 2-Port Serial High-Speed WAN Interface Card, providing 2 serial ports.
PROBLEM
The Corp router is not showing the expected available interfaces. I need to connect R1 to the S0/0/0 interface on Corp and R2 to the S0/0/1 interface on Corp.
My Corp router is not showing those interfaces:
Solution
the placement of the cards on the router determines which interface numbers will be available.
In this case, it seems the interfaces start from the bottom right corner and increase on each slot moving clockwise. I found this out by filling all four slots on my router
which led to all interfaces being available. I then ran a card in each slot individually to isolate which interface numbers correspond to each slot:
Interestingly, while the physical slots seem to follow a 'clockwise' pattern, the list of available slots in the logical diagram does not;
We get an output of interfaces corresponding to slot 2, then 3, 1, and 4. This is a 'bottom to top' then 'left to right' pattern. Tricky.
Having said all that... I will run cards in slots 1 and 2 for this lab since we only need interfaces S0/0/0, S0/0/1, S0/1/0
The Router topology:
I'm not clear on the connections from R1 and R2 to the clients.. I assume there are switches involved.
For now I will follow the next steps in the book which
are to configure the corp router as follows:
Router(config)#
hostname Corp
Corp(config)#
enable secret todd
Corp(config)#
interface vlan 1
Corp(config-if)#
description Switch Card to Core Network
Corp(config-if)#
ip address 10.1.1.1 255.255.255.0
Corp(config-if)#
no shut
----------------------------------------------------------------------------------------------------------------
Corp(config-if)#
int f1/0
Corp(config-if)#
description Switch Port connection to WWW Server
Corp(config-if)#
no shutdown
Corp(config-if)#
int f1/1
Corp(config-if)#
description Switch Port connection to Email Server
Corp(config-if)#
no shutdown
Corp(config-if)#
int f1/2
Corp(config-if)#
description Switch Port connection to DNS Server
Corp(config-if)#
no shutdown
----------------------------------------------------------------------------------------------------------------
Corp(config-if)#
int s0/0/0
Corp(config-if)#
description 1st Connection to R1
Corp(config-if)#
ip address 10.1.2.1 255.255.255.0
Corp(config-if)#
no shut
Corp(config-if)#
int s0/0/1
Corp(config-if)#
description 2nd Connection to R1
Corp(config-if)#
ip address 10.1.3.1 255.255.255.0
Corp(config-if)#
no shut
Corp(config-if)#
int s0/1/0
Corp(config-if)#
description Connection to R2
Corp(config-if)#
ip address 10.1.4.1 255.255.255.0
Corp(config-if)#
no shut
Corp(config-if)#
int fa0/0
Corp(config-if)#
description Connection to R3
Corp(config-if)#
ip address 10.1.5.1 255.255.255.0
Corp(config-if)#
no shut
----------------------------------------------------------------------------------------------------------------
Corp(config-if)#
line con 0
Corp(config-if)#
password console
Corp(config-if)#
login
Corp(config-if)#
logging synchro
Corp(config-if)#
exec-timeout 0 0
----------------------------------------------------------------------------------------------------------------
Corp(config-if)#
line aux 0
Corp(config-if)#
password aux
Corp(config-if)#
login
Corp(config-if)#
exit
----------------------------------------------------------------------------------------------------------------
Corp(config)#
line vty ?
<1-15>Last Line number
Corp(config)#
line vty 0 15
Corp(config-if)#
password telnet
Corp(config-if)#
login
Corp(config-if)#
exit
----------------------------------------------------------------------------------------------------------------
Corp(config)#
no ip domain lookup
Corp(config)#
banner motd # This is my Corp 2811 ISR Router #
Ctrl + Z
%SYS-5-CONFIG_I: Configured from console by console
(Ctrl-Z: When in a config mode, ends the config mode and returns you to privileged EXEC mode.... same as typing exit(?))
Corp#
copy run start
Destination filename [startup-config]?
Building configuration...
[OK]
----------------------------------------------------------------------------------------------------------------
Corp#
show ip int br
Interface IP-Address OK? Method Status Protocol
FastEthernet0/0 10.1.5.1 YES manual up down
FastEthernet0/1 unassigned YES unset administratively down down
Serial0/0/0 10.1.2.1 YES manual down down
Serial0/0/1 10.1.3.1 YES manual down down
Serial0/1/0 10.1.4.1 YES manual down down
Serial0/1/1 unassigned YES unset administratively down down
FastEthernet1/0 unassigned YES unset up up
FastEthernet1/1 unassigned YES unset up up
FastEthernet1/2 unassigned YES unset up up
FastEthernet1/3 unassigned YES unset administratively down down
FastEthernet1/4 unassigned YES unset administratively down down
FastEthernet1/5 unassigned YES unset administratively down down
FastEthernet1/6 unassigned YES unset administratively down down
FastEthernet1/7 unassigned YES unset administratively down down
FastEthernet1/8 unassigned YES unset administratively down down
FastEthernet1/9 unassigned YES unset administratively down down
FastEthernet1/10 unassigned YES unset administratively down down
FastEthernet1/11 unassigned YES unset administratively down down
FastEthernet1/12 unassigned YES unset administratively down down
FastEthernet1/13 unassigned YES unset administratively down down
FastEthernet1/14 unassigned YES unset administratively down down
FastEthernet1/15 unassigned YES unset administratively down down
Vlan1 10.1.1.1 YES manual up up
----------------------------------------------------------------------------------------------------------------
Corp#
show run
Building configuration...
Current configuration : 2073 bytes
!
version 15.1
no service timestamps log datetime msec
no service timestamps debug datetime msec
no service password-encryption
!
hostname Corp
!
!
!
enable secret 5 $1$mERr$V5ujdIM9bTB/I.ipB0gkJ0
!
!
!
!
!
!
no ip cef
no ipv6 cef
!
!
!
!
license udi pid CISCO2811/K9 sn FTX1017U440-
!
!
!
!
!
!
!
!
!
no ip domain-lookup
!
!
spanning-tree mode pvst
!
!
!
!
!
!
interface FastEthernet0/0
description connection to R3
ip address 10.1.5.1 255.255.255.0
duplex auto
speed auto
!
interface FastEthernet0/1
no ip address
duplex auto
speed auto
shutdown
!
interface Serial0/0/0
description 1st connection to R1
ip address 10.1.2.1 255.255.255.0
clock rate 2000000
!
interface Serial0/0/1
description 2nd connection to R1
ip address 10.1.3.1 255.255.255.0
clock rate 2000000
!
interface Serial0/1/0
description connection to R2
ip address 10.1.4.1 255.255.255.0
!
interface Serial0/1/1
no ip address
clock rate 2000000
shutdown
!
interface FastEthernet1/0
description switch port connection to WWW Server
!
interface FastEthernet1/1
description switch port connection to Email Server
!
interface FastEthernet1/2
description switch port connection to DNS Server
!
interface FastEthernet1/3
shutdown
!
interface FastEthernet1/4
shutdown
!
interface FastEthernet1/5
shutdown
!
interface FastEthernet1/6
shutdown
!
interface FastEthernet1/7
shutdown
!
interface FastEthernet1/8
shutdown
!
interface FastEthernet1/9
shutdown
!
interface FastEthernet1/10
shutdown
!
interface FastEthernet1/11
shutdown
!
interface FastEthernet1/12
shutdown
!
interface FastEthernet1/13
shutdown
!
interface FastEthernet1/14
shutdown
!
interface FastEthernet1/15
shutdown
!
interface Vlan1
description Switch Card to Core Network
ip address 10.1.1.1 255.255.255.0
!
ip classless
!
ip flow-export version 9
!
!
!
banner motd ^C This is my Corp 2811 ISR Router ^C
!
!
!
!
!
line con 0
exec-timeout 0 0
password console
logging synchronous
login
!
line aux 0
password aux
login
!
line vty 0 4
password telnet
login
line vty 5 15
password telnet
login
!
!
!
end
-----------------------------------------------------------------------------------------------------------------------
more configurations:
R1
Router(config)#
hostname R1
R1(config)#
enable secret todd
R1(config)#
int s0/0/0
R1(config-if)#
ip address 10.1.2.2 255.255.255.0
R1(config-if)#
Decription 1st connection to corp router
R1(config-if)#
no shut
-----------------------------------------------------------------------------------------------
R1(config-if)#
int s0/0/1
R1(config-if)#
ip address 10.1.3.2 255.255.255.0
R1(config-if)#
Decription 2nd connection to corp router
R1(config-if)#
no shut
-----------------------------------------------------------------------------------------------
R1(config-if)#
int f0/0
R1(config-if)#
ip address 192.168.10.1 255.255.255.0
R1(config-if)#
Decription connection to finance
R1(config-if)#
no shut
-----------------------------------------------------------------------------------------------
R1(config-if)#
int f0/1
R1(config-if)#
ip address 192.168.20.1 255.255.255.0
R1(config-if)#
Decription connection to marketing
R1(config-if)#
no shut
R1(config-if)#
exit
-----------------------------------------------------------------------------------------------
R1(config)#
line con 0
R1(config-line)#
password console
R1(config-line)#
login
R1(config-line)#
logging synchronous
R1(config-line)#
exec-timeout 0 0
-----------------------------------------------------------------------------------------------
R1(config-line)#
line aux 0
R1(config-line)#
password aux
R1(config-line)#
login
R1(config-line)#
exit
-----------------------------------------------------------------------------------------------
R1(config)#
line vty 0 ?
<0-15> Last Line number
R1(config)#
line vty 0 807
R1(config-line)#
password telnet
R1(config-line)#
login
R1(config-line)#
banner motd # This is my R1 Router #
R1(config-line)#
exit
-----------------------------------------------------------------------------------------------
R1(config)#
no ip domain-lookup
R1(config)#
exit
R1#
copy run start
R2
Router(config)#
hostname R2
R2(config)#
enable secret todd
R2(config)#
int s0/0/0
R2(config-if)#
ip address 10.1.4.2 255.255.255.0
R2(config-if)#
description connection to corp router
R2(config-if)#
no shut
-----------------------------------------------------------------------------------------------
R2(config-if)#
int f0/0
R2(config-if)#
ip address 192.168.30.1 255.255.255.0
R2(config-if)#
description connection to sales PC
R2(config-if)#
no shut
-----------------------------------------------------------------------------------------------
R2(config-if)#
int f0/1
R2(config-if)#
ip address 192.168.40.1 255.255.255.0
R2(config-if)#
description connection to HR pc
R2(config-if)#
no shut
-----------------------------------------------------------------------------------------------
R2(config-if)#
line con 0
R2(config-line)#
password console
R2(config-line)#
login
R2(config-line)#
logging synchronous
R2(config-line)#
exec-timeout 0 0
-----------------------------------------------------------------------------------------------
R2(config-line)#
line aux 0
R2(config-line)#
password aux
R2(config-line)#
login
R2(config-line)#
exit
-----------------------------------------------------------------------------------------------
R2(config)#
line vty 0 ?
<0-15> Last Line number
R2(config)#
line vty 0 807
R2(config-line)#
password telnet
R2(config-line)#
login
R2(config-line)#
banner motd # This is my R1 Router #
R2(config-line)#
exit
-----------------------------------------------------------------------------------------------
R2(config)#
no ip domain-lookup
R2(config)#
exit
R2#
copy run start
R3
Router(config)#
hostname R3
R3(config)#
enable secret todd
R3(config)#
int f0/0
R3(config-if)#
ip address 10.1.5.2 255.255.255.0
R3(config-if)#
description connection to corp router
R3(config-if)#
no shut
-----------------------------------------------------------------------------------------------
R3(config-if)#
int dot11radio0/0/0
R3(config-if)#
ip address 172.16.10.1 255.255.255.0
R3(config-if)#
description WLAN for mobile user
R3(config-if)#
no shut
R3(config-if)#
ssid ADMIN
stuck here 2-5-22-- packet tracer isnt taking me into the config-if-ssid prompt
R3(config-if-ssid)#
guest-mode
R3(config-if-ssid)#
authentication open
R3(config-if-ssid)#
ingrastructure-ssid
R3(config-if-ssid)#
exit
-----------------------------------------------------------------------------------------------
R3(config-if)#
line con 0
R3(config-line)#
password console
R3(config-line)#
login
R3(config-line)#
logging synchronous
R3(config-line)#
exec-timeout 0 0
-----------------------------------------------------------------------------------------------
R3(config-line)#
line aux 0
R3(config-line)#
password aux
R3(config-line)#
login
R3(config-line)#
exit
-----------------------------------------------------------------------------------------------
R3(config)#
line vty 0 ?
<0-15> Last Line number
R3(config)#
line vty 0 807
R3(config-line)#
password telnet
R3(config-line)#
login
R3(config-line)#
banner motd # This is my R1 Router #
R3(config-line)#
exit
-----------------------------------------------------------------------------------------------
R3(config)#
no ip domain-lookup
R3(config)#
exit
R3#
copy run start
PROBLEM
i cant get into conf-if-ssid prompt
R3(config-if)#
ssid ADMIN
%LINK-5-CHANGED: Interface Dot11Radio0/0/0, changed state to administratively down
%LINEPROTO-5-UPDOWN: Line protocol on Interface Dot11Radio0/0/0, changed state to down
%LINK-5-CHANGED: Interface Dot11Radio0/0/0, changed state to up
%LINEPROTO-5-UPDOWN: Line protocol on Interface Dot11Radio0/0/0, changed state to up
R3(config-if)#
research led me to this thread, which is a dead end:
further research led me here:
R3(config)# global config mode
R3(config)#
dot11 ssid ADMIN
creates an SSID or lets you config an existing SSID
R3(config-ssid)#
guest-mode
R3(config-ssid)#
%LINK-5-CHANGED: Interface Dot11Radio0/0/0, changed state to administratively down
%LINEPROTO-5-UPDOWN: Line protocol on Interface Dot11Radio0/0/0, changed state to down
%LINK-5-CHANGED: Interface Dot11Radio0/0/0, changed state to up
%LINEPROTO-5-UPDOWN: Line protocol on Interface Dot11Radio0/0/0, changed state to up
R3(config-ssid)#
authentication open
R3(config-ssid)#
%LINK-5-CHANGED: Interface Dot11Radio0/0/0, changed state to administratively down
%LINEPROTO-5-UPDOWN: Line protocol on Interface Dot11Radio0/0/0, changed state to down
%LINK-5-CHANGED: Interface Dot11Radio0/0/0, changed state to up
%LINEPROTO-5-UPDOWN: Line protocol on Interface Dot11Radio0/0/0, changed state to up
R3(config-ssid)#
infrastructure-ssid
R3(config-ssid)#infrastructure-ssid
^
% Invalid input detected at '^' marker.
this command given by the book doesnt appear to be valid
R3(config-ssid)#
?
authentication authentication method
exit Exit from ssid sub mode
guest-mode guest ssid
no Negate a command or set it's defaults
wpa-psk Configure Wi-Fi Protected Access pre-shared key
back into the interface to see what the options are
R3(config-ssid)#
int dot110/0/0
R3(config-if)#
?
arp Set arp type (arpa, probe, snap) or timeout or log options
bandwidth Set bandwidth informational parameter
cdp CDP interface subcommands
crypto Encryption/Decryption commands
delay Specify interface throughput delay
description Interface specific description
encryption Configure dot11 encryption parameters
exit Exit from interface configuration mode
fair-queue Enable Fair Queuing on an Interface
hold-queue Set hold queue depth
ip Interface Internet Protocol config commands
mac-address Manually set interface MAC address
mtu Set the interface Maximum Transmission Unit (MTU)
no Negate a command or set its defaults
priority-group Assign a priority group to an interface
service-policy Configure QoS Service Policy
shutdown Shutdown the selected interface
speed Set allowed radio bit rates
ssid Configure radio service set parameters
tx-ring-limit Configure PA level transmit ring limit
i'll consider the problem *mostly* solved. I was able to assign the SSD.
The infrastructure command may be expendable in this case... to be determined
here is our configuration for R3
R3#
show run
Building configuration...
Current configuration : 1682 bytes
!
version 15.1
no service timestamps log datetime msec
no service timestamps debug datetime msec
no service password-encryption
!
hostname R3
!
!
!
enable secret 5 $1$mERr$V5ujdIM9bTB/I.ipB0gkJ0
!
!
ip dhcp excluded-address 172.16.10.1 172.16.10.10
!
ip dhcp pool Admin
network 172.16.10.0 255.255.255.0
default-router 172.16.10.1
!
dot11 ssid ADMIN
authentication open
guest-mode
!
dot11 ssid ADMIN2
authentication open
guest-mode
!
!
!
ip cef
no ipv6 cef
!
!
!
!
license udi pid CISCO2811/K9 sn FTX1017RE40-
!
!
!
!
!
!
!
!
!
no ip domain-lookup
ip name-server 172.16.10.4
!
!
spanning-tree mode pvst
!
!
!
!
!
!
interface FastEthernet0/0
description connection to corp router
ip address 10.1.5.2 255.255.255.0
duplex auto
speed auto
!
interface FastEthernet0/1
no ip address
duplex auto
speed auto
shutdown
!
interface Dot11Radio0/0/0
description WAN for mobile
ip address 172.16.10.1 255.255.255.0
speed 12.0 18.0 24.0 36.0 48.0 54.0 6.0 9.0 basic-1.0 basic-11.0 basic-2.0 basic-5.5
ssid ADMIN2
!
interface Dot11Radio0/0/1
no ip address
speed 18.0 36.0 48.0 54.0 9.0 basic-12.0 basic-24.0 basic-6.0
!
interface Serial0/1/0
no ip address
clock rate 2000000
!
interface Serial0/1/1
no ip address
clock rate 2000000
!
interface Vlan1
no ip address
shutdown
!
router rip
version 2
network 10.0.0.0
network 172.16.0.0
!
ip classless
ip route 0.0.0.0 0.0.0.0 10.1.5.1
!
ip flow-export version 9
!
!
!
banner motd ^C this is R3 $
this is R3 ^C
!
!
!
!
!
line con 0
exec-timeout 0 0
password console
logging synchronous
login
!
line aux 0
password aux
login
!
line vty 0 4
password telnet
login
line vty 5 15
password telnet
login
!
!
!
end
to summarize...
the book is a little off here.
-----------------------------------------------------------------------------------------------
R3(config-if)#
int dot11radio0/0/0
R3(config-if)#
ip address 172.16.10.1 255.255.255.0
R3(config-if)#
description WLAN for mobile user
R3(config-if)#
no shut
at this point we have created a wireless interface with an IP address but no SSID exists on this router
interface Dot11Radio0/0/0
description test router 2
ip address 172.16.10.1 255.255.255.0
speed 12.0 18.0 24.0 36.0 48.0 54.0 6.0 9.0 basic-1.0 basic-11.0 basic-2.0 basic-5.5
Trying to use the command "ssid ADMIN" doesnt work here. The below commands are invalid here:
R3(config-if)#
ssid ADMIN
R3(config-if-ssid)#
guest-mode
R3(config-if-ssid)#
authentication open
R3(config-if-ssid)#
ingrastructure-ssid
R3(config-if-ssid)#
exit
-----------------------------------------------------------------------------------------------
We need to drop out of config-if, back to config, and enter SSID config mode
-----------------------------------------------------------------------------------------------
R3(config-if)#
exit
R3(config)#
dot11 ssid ADMIN2 creates an ssid named ADMIN2, and puts us into SSID config mode
R3(config-ssid)#
guest-mode
R3(config-ssid)#
authentication open
then out of config-ssid and back to interface config
R3(config-ssid)#
exit
R3(config)
int dot11r0/0/0
R3(config-if)
?
arp Set arp type (arpa, probe, snap) or timeout or log options
bandwidth Set bandwidth informational parameter
cdp CDP interface subcommands
crypto Encryption/Decryption commands
delay Specify interface throughput delay
description Interface specific description
encryption Configure dot11 encryption parameters
exit Exit from interface configuration mode
fair-queue Enable Fair Queuing on an Interface
hold-queue Set hold queue depth
ip Interface Internet Protocol config commands
mac-address Manually set interface MAC address
mtu Set the interface Maximum Transmission Unit (MTU)
no Negate a command or set its defaults
priority-group Assign a priority group to an interface
service-policy Configure QoS Service Policy
shutdown Shutdown the selected interface
speed Set allowed radio bit rates
ssid Configure radio service set parameters
tx-ring-limit Configure PA level transmit ring limit
we have the option for ssid
R3(config-if)
ssid ADMIN2
%LINK-5-CHANGED: Interface Dot11Radio0/0/0, changed state to administratively down
%LINEPROTO-5-UPDOWN: Line protocol on Interface Dot11Radio0/0/0, changed state to down
%LINK-5-CHANGED: Interface Dot11Radio0/0/0, changed state to up
%LINEPROTO-5-UPDOWN: Line protocol on Interface Dot11Radio0/0/0, changed state to up
the router resets the interface..
-----------------------------------------------------------------------------------------------
R3(config-if)
do show run
[cut]
!
!
dot11 ssid ADMIN2
authentication open
guest-mode
!
!
[cut]
!
interface Dot11Radio0/0/0
description test router 2
ip address 172.16.10.1 255.255.255.0
speed 12.0 18.0 24.0 36.0 48.0 54.0 6.0 9.0 basic-1.0 basic-11.0 basic-2.0 basic-5.5
ssid ADMIN2
!
[cut]
the SSID is created and assigned to the interface
To summarize.
Wrong: create the dot11 interface, then create the SSID from CONFIG-IF mode, which puts you into CONFIG-IF-SSID (there is no such mode on this router) mode, then modify the ssid from there...
Correct: create the dot11 interface. Exit CONFIG-IF and go back to GLOBAL CONFIG. Create the SSID which puts you in CONFIG-SSID mode.
Configure the ssid. Then exit CONFIG-SSID. Back into CONFIG-IF, assign the SSID
We have one more task for R3- Configuring the DHCP pool for wireless clients.
R3(config)#
ip dhcp pool Admin creating the pool name as "Admin"
R3(dhcp-config)#
network 172.16.10.0 255.255.255.0
R3(dhcp-config)#
default-router 172.16.10.1 aka default-gateway for clients in the pool
R3(dhcp-config)#
ip name-server 172.16.10.4 dns server
*automatically exits dhcp-config prompt*
R3(config)#
ip dhcp excluded-address 172.16.10.1 172.16.10.10 excludes the range given
172.16.10.1 is the router interface- we need to specifically exclude it from the pool
this setup should allow the wireless client to pick up an IP after connecting to the open SSID.
However, I was having trouble at first-
even though I seemed to have the SSID set correctly, i was hitting a WEP password prompt
i didnt see any obvious issues with the wifi module im using on the laptop:
The Linksys-WPC300N module provides one 2.4GHz wireless interface suitable for connection to wireless networks.
The module supports protocols that use Ethernet for LAN access.
I ended up creating a new SSID, with the same settings as the original:
R3(config)#
dot11 ssid ADMIN2
R3(config-ssid)#
guest-mode
R3(config-ssid)#
authentication open
and then I assigned the ip address to ssid ADMIN2 instead of the orginal ADMIN ssid
R3(config)#
int dot110/0/0
R3(config-if)#
ip address 172.16.10.1 255.255.255.0
R3(config-if)#
description WLAN for mobile user
R3(config-if)#
no shut
R3(config-if)#
ssid ADMIN2
R3#
show run
Building configuration...
Current configuration : 1467 bytes
!
version 15.1
no service timestamps log datetime msec
no service timestamps debug datetime msec
no service password-encryption
!
hostname R3
!
!
!
enable secret 5 $1$mERr$V5ujdIM9bTB/I.ipB0gkJ0
!
!
ip dhcp excluded-address 172.16.10.1 172.16.10.10
!
ip dhcp pool Admin
network 172.16.10.0 255.255.255.0
default-router 172.16.10.1
!
dot11 ssid ADMIN
authentication open
guest-mode
!
dot11 ssid ADMIN2
authentication open
guest-mode
!
!
!
ip cef
no ipv6 cef
!
!
!
!
license udi pid CISCO2811/K9 sn FTX1017RE40-
!
!
!
!
!
!
!
!
!
no ip domain-lookup
ip name-server 172.16.10.4
!
!
spanning-tree mode pvst
!
!
!
!
!
!
interface FastEthernet0/0
description connection to corp router
ip address 10.1.5.2 255.255.255.0
duplex auto
speed auto
!
interface FastEthernet0/1
no ip address
duplex auto
speed auto
shutdown
!
interface Dot11Radio0/0/0
description WAN for mobile
ip address 172.16.10.1 255.255.255.0
speed 12.0 18.0 24.0 36.0 48.0 54.0 6.0 9.0 basic-1.0 basic-11.0 basic-2.0 basic-5.5
ssid ADMIN2
!
interface Dot11Radio0/0/1
no ip address
speed 18.0 36.0 48.0 54.0 9.0 basic-12.0 basic-24.0 basic-6.0
!
interface Vlan1
no ip address
shutdown
!
ip classless
!
ip flow-export version 9
!
!
!
banner motd ^C this is R3 $
this is R3 ^C
!
!
!
!
!
line con 0
exec-timeout 0 0
password console
logging synchronous
login
!
line aux 0
password aux
login
!
line vty 0 4
password telnet
login
line vty 5 15
password telnet
login
!
!
!
end
Recall the DHCP configuration on R3:
R3(config)#
ip dhcp pool Admin creating the pool name as "Admin"
R3(dhcp-config)#
network 172.16.10.0 255.255.255.0
R3(dhcp-config)#
default-router 172.16.10.1 aka default-gateway for clients in the pool
R3(dhcp-config)#
ip name-server 172.16.10.4 dns server
*automatically exits dhcp-config prompt*
R3(config)#
ip dhcp excluded-address 172.16.10.1 172.16.10.10 excludes the range given
172.16.10.1 is the router interface- we need to specifically exclude it from the pool
we can check the configuration:
R3#
show ip dhcp pool
Pool Admin :
Utilization mark (high/low) : 100 / 0
Subnet size (first/next) : 0 / 0
Total addresses : 254
Leased addresses : 1
Excluded addresses : 1
Pending event : none
1 subnet is currently in the pool
Current index IP address range Leased/Excluded/Total
172.16.10.1 172.16.10.1 - 172.16.10.254 1 / 1 / 254
R3#
show ip dhcp binding
IP address Client-ID/ Lease expiration Type
Hardware address
172.16.10.11 00D0.979A.733B -- Automatic
the show command is becoming more familiar
R3#
show ip?
access-lists List access lists
arp IP ARP table
bgp BGP information
cache IP fast-switching route cache
cef Cisco Express Forwarding
dhcp Show items in the DHCP database
eigrp IP-EIGRP show commands
inspect CBAC (Context Based Access Control) information
interface IP interface status and configuration
ips IPS (Intrusion Prevention System) information
nat IP NAT information
nbar Network-Based Application Recognition
ospf OSPF information
protocols IP routing protocol process parameters and statistics
rip IP RIP show commands
route IP routing table
ssh Information on SSH
we'll use show ip route soon on all the routers. For now, here is the output for R3:
R3#
show ip route
Codes: L - local, C - connected, S - static, R - RIP, M - mobile, B - BGP
D - EIGRP, EX - EIGRP external, O - OSPF, IA - OSPF inter area
N1 - OSPF NSSA external type 1, N2 - OSPF NSSA external type 2
E1 - OSPF external type 1, E2 - OSPF external type 2, E - EGP
i - IS-IS, L1 - IS-IS level-1, L2 - IS-IS level-2, ia - IS-IS inter area
* - candidate default, U - per-user static route, o - ODR
P - periodic downloaded static route
Gateway of last resort is not set
10.0.0.0/8 is variably subnetted, 2 subnets, 2 masks
C 10.1.5.0/24 is directly connected, FastEthernet0/0
L 10.1.5.2/32 is directly connected, FastEthernet0/0
172.16.0.0/16 is variably subnetted, 2 subnets, 2 masks
C 172.16.10.0/24 is directly connected, Dot11Radio0/0/0
L 172.16.10.1/32 is directly connected, Dot11Radio0/0/0
Before moving on to the routing configurations, here is a review of the topology
I have switched over to the DrawIO diagram app to lay out the topology.
The Packet Tracer diagram becomes
too crowded to see the labels; it's labeling system forces awkward positioning of the objects; the interface
label's cant be moved, so if objects are too close together their labels cover eachother.. not good.
DrawIO allows a cleaner layout with plenty of room to label interfaces and ip addresses.
As a compromise, I'll use both.
I have the packet tracer objects spread out just enough to see the interfaces
and the label for each router. From here I can jump into the CLI for each device.
The DrawIO diagram allows me to cleary see IP addresses
I want to also review all of the configurations we just performed:
PROBLEM
The book specifies that of the two serial conections between R1 and Corp, there should be a DCE on each end..
Both of my DCE's are on the same end.
First lets be sure we understand what DCE means:
networkengineering.stackexchange.com/
One side of the link (DCE), has to transmit the clock signal, which controls the data rate, and the other side (DTE) receives the clock signal.
That is good enough for now. Note that while the book does specify in the diagram that each side should have a DCE, it was not actually mentioned in the configs.
We did not set a DCE or clock rate when conifguring those interfaces.
To fix this in my Packet Tracer topology, I did some quick research:
While this post wasnt pertaining to Packet Tracer, it got me thinking about the cable itself.
I deleted both of my existing serial connections and looked at the options for creating a new cable.
I noticed one is a DCE and one is a DTE:
Fixed the issue
back to the configuration overview: 4 routers, abbreviated show run output
Corp
interface FastEthernet0/0
description connection to R3
ip address 10.1.5.1 255.255.255.0
duplex auto
speed auto
!
interface FastEthernet0/1
no ip address
duplex auto
speed auto
shutdown
!
interface Serial0/0/0
description 1st connection to R1
ip address 10.1.2.1 255.255.255.0
!
interface Serial0/0/1
description 2nd connection to R1
ip address 10.1.3.1 255.255.255.0
clock rate 2000000
!
interface Serial0/1/0
description connection to R2
ip address 10.1.4.1 255.255.255.0
!
interface Vlan1
description Switch Card to Core Network
ip address 10.1.1.1 255.255.255.0
!
interface FastEthernet1/0
description switch port connection to WWW Server
switchport mode access
switchport nonegotiate
!
interface FastEthernet1/1
description switch port connection to Email Server
switchport mode access
switchport nonegotiate
!
interface FastEthernet1/2
description switch port connection to DNS Server
switchport mode access
switchport nonegotiate
!
R1
interface FastEthernet0/0
description connection to Finance
ip address 192.168.10.1 255.255.255.0
duplex auto
speed auto
!
interface FastEthernet0/1
description connection to Marketing
ip address 192.168.20.1 255.255.255.0
duplex auto
speed auto
!
interface Serial0/0/0
description 1st connection to Corp router
ip address 10.1.2.2 255.255.255.0
clock rate 2000000
!
interface Serial0/0/1
description 2nd connecction to Corp router
ip address 10.1.3.2 255.255.255.0
!
R2
interface FastEthernet0/0
description Connection to Sales PC
ip address 192.168.30.1 255.255.255.0
duplex auto
speed auto
!
interface FastEthernet0/1
description Connection to HR PC
ip address 192.168.40.1 255.255.255.0
duplex auto
speed auto
!
interface Serial0/0/0
description Connection to Corp Router
ip address 10.1.4.2 255.255.255.0
clock rate 2000000
!
interface Serial0/0/1
no ip address
clock rate 2000000
shutdown
!
R3
interface FastEthernet0/0
description connection to corp router
ip address 10.1.5.2 255.255.255.0
duplex auto
speed auto
!
interface FastEthernet0/1
no ip address
duplex auto
speed auto
shutdown
!
interface Dot11Radio0/0/0
description WAN for mobile
ip address 172.16.10.1 255.255.255.0
speed 12.0 18.0 24.0 36.0 48.0 54.0 6.0 9.0 basic-1.0 basic-11.0 basic-2.0 basic-5.5
ssid ADMIN2
and here is the output of show ip route for each router
Codes: C - connected, S - static, I - IGRP, R - RIP, M - mobile, B - BGP
D - EIGRP, EX - EIGRP external, O - OSPF, IA - OSPF inter area
N1 - OSPF NSSA external type 1, N2 - OSPF NSSA external type 2
E1 - OSPF external type 1, E2 - OSPF external type 2, E - EGP
i - IS-IS, L1 - IS-IS level-1, L2 - IS-IS level-2, ia - IS-IS inter area
* - candidate default, U - per-user static route, o - ODR
P - periodic downloaded static route
Gateway of last resort is not set
Corp
10.0.0.0/24 is subnetted, 2 subnets
C 10.1.2.0 is directly connected, Serial0/0/0
C 10.1.3.0 is directly connected, Serial0/0/1
C 192.168.10.0/24 is directly connected, FastEthernet0/0
C 192.168.20.0/24 is directly connected, FastEthernet0/1
R1
10.0.0.0/24 is subnetted, 2 subnets
C 10.1.2.0 is directly connected, Serial0/0/0
C 10.1.3.0 is directly connected, Serial0/0/1
C 192.168.10.0/24 is directly connected, FastEthernet0/0
C 192.168.20.0/24 is directly connected, FastEthernet0/1
R2
10.0.0.0/24 is subnetted, 1 subnets
C 10.1.4.0 is directly connected, Serial0/0/0
C 192.168.30.0/24 is directly connected, FastEthernet0/0
C 192.168.40.0/24 is directly connected, FastEthernet0/1
R3
10.0.0.0/8 is variably subnetted, 2 subnets, 2 masks
C 10.1.5.0/24 is directly connected, FastEthernet0/0
L 10.1.5.2/32 is directly connected, FastEthernet0/0
172.16.0.0/16 is variably subnetted, 2 subnets, 2 masks
C 172.16.10.0/24 is directly connected, Dot11Radio0/0/0
L 172.16.10.1/32 is directly connected, Dot11Radio0/0/0
Note that this is before we have configured any 'routing'. We are seeing configured, directly connected networks.
The output for R3 is particularly interesting
What does 'variably' subnetted mean, and what is the "L" next to these routes. And why do they have a mask of 32?
R3
10.0.0.0/8 is variably subnetted, 2 subnets, 2 masks
C 10.1.5.0/24 is directly connected, FastEthernet0/0
L 10.1.5.2/32 is directly connected, FastEthernet0/0
172.16.0.0/16 is variably subnetted, 2 subnets, 2 masks
C 172.16.10.0/24 is directly connected, Dot11Radio0/0/0
L 172.16.10.1/32 is directly connected, Dot11Radio0/0/0
Cisco forums
That makes sense, but my question is why did the other routing tables not behave the same way? R3 is the only one that shows "L" routes.
The book tells us we're using two different model routers, and indeed they are running different IOS versions:
NOTE that at the time the book was published IOS 15 was not released yet, so the book assumes all routers are running 12.4
But that still doesnt explain why Corp and R3 are behaving differently..
Corp
10.0.0.0/24 is subnetted, 2 subnets
C 10.1.2.0 is directly connected, Serial0/0/0
C 10.1.3.0 is directly connected, Serial0/0/1
C 192.168.10.0/24 is directly connected, FastEthernet0/0
C 192.168.20.0/24 is directly connected, FastEthernet0/1
R1
10.0.0.0/24 is subnetted, 2 subnets
C 10.1.2.0 is directly connected, Serial0/0/0
C 10.1.3.0 is directly connected, Serial0/0/1
C 192.168.10.0/24 is directly connected, FastEthernet0/0
C 192.168.20.0/24 is directly connected, FastEthernet0/1
R2
10.0.0.0/24 is subnetted, 1 subnets
C 10.1.4.0 is directly connected, Serial0/0/0
C 192.168.30.0/24 is directly connected, FastEthernet0/0
C 192.168.40.0/24 is directly connected, FastEthernet0/1
R3
10.0.0.0/8 is variably subnetted, 2 subnets, 2 masks
C 10.1.5.0/24 is directly connected, FastEthernet0/0
L 10.1.5.2/32 is directly connected, FastEthernet0/0
172.16.0.0/16 is variably subnetted, 2 subnets, 2 masks
C 172.16.10.0/24 is directly connected, Dot11Radio0/0/0
L 172.16.10.1/32 is directly connected, Dot11Radio0/0/0
how are Corp and R3 different?
The answer is, they are not...
I have accidentally displayed the R1 output to the Corp windows. Error in translating data from the IOS to this webpage..
here's the corrected output.
Corp
10.0.0.0/8 is variably subnetted, 10 subnets, 2 masks
C 10.1.1.0/24 is directly connected, Vlan1
L 10.1.1.1/32 is directly connected, Vlan1
C 10.1.2.0/24 is directly connected, Serial0/0/0
L 10.1.2.1/32 is directly connected, Serial0/0/0
C 10.1.3.0/24 is directly connected, Serial0/0/1
L 10.1.3.1/32 is directly connected, Serial0/0/1
C 10.1.4.0/24 is directly connected, Serial0/1/0
L 10.1.4.1/32 is directly connected, Serial0/1/0
C 10.1.5.0/24 is directly connected, FastEthernet0/0
L 10.1.5.1/32 is directly connected, FastEthernet0/0
R1
10.0.0.0/24 is subnetted, 2 subnets
C 10.1.2.0 is directly connected, Serial0/0/0
C 10.1.3.0 is directly connected, Serial0/0/1
C 192.168.10.0/24 is directly connected, FastEthernet0/0
C 192.168.20.0/24 is directly connected, FastEthernet0/1
R2
10.0.0.0/24 is subnetted, 1 subnets
C 10.1.4.0 is directly connected, Serial0/0/0
C 192.168.30.0/24 is directly connected, FastEthernet0/0
C 192.168.40.0/24 is directly connected, FastEthernet0/1
R3
10.0.0.0/8 is variably subnetted, 2 subnets, 2 masks
C 10.1.5.0/24 is directly connected, FastEthernet0/0
L 10.1.5.2/32 is directly connected, FastEthernet0/0
172.16.0.0/16 is variably subnetted, 2 subnets, 2 masks
C 172.16.10.0/24 is directly connected, Dot11Radio0/0/0
L 172.16.10.1/32 is directly connected, Dot11Radio0/0/0
We do indeed see consistent behavior differences between IOS versions 12.4 and 15.1
recap Corp and R3 outputs:
update topology with Router versions
That covers the first half of Chapter 8. Now we are ready to configure IP routing on our network.
There are three ways: Static, Default, Dynamic
To set up static routes, we simply need to program the routes using the ip route command
Syntax
ip route
[
destination network
]
[
mask
]
[
next hop
]
[
exitinterface
]
[
administrative distance
]
[
permanent
]
destination network and mask
the network data we're adding to the routing table
next-hop address
the address of the next-hop router that will receive the packet and forward to the remote network.
This is the IP address of a router interface that is directly connected.
It must be pingable.
exit interface
can be used instead of next hop address
administrative distance
by default, static routes have an admin distance of 1 if you use a next hop, or 0 if you use exit interface.
You can change the value by adding an administrative weight at the end of the command. More on this later with dynamic routing.
permanent
if the interface is shut down or the router cant communicate to the next hp router, the route will automatically be discarded from the table by default.
The 'permanent' option keeps the entry in the routing table indefenitely.
-----------------------------------------------------------------------------------------------------
Corp has automatically picked up 5 routes that are directly connected:
10.1.1.0 to corp switch card
10.1.2.0 to R1
10.1.3.0 to R1
10.1.4.0 to R2
10.1.5.0 to R3
We need to program 5 more routes:
192.168.10.0 traverse R1
192.168.20.0 traverse R1
192.168.30.0 traverse R1
192.168.40.0 traverse R2
172.16.10.0 traverse R3
-----------------------------------------------------------------------------------------------------
R1 has automatically picked up 4 routes that are directly connected:
10.1.2.0
10.1.3.0
192.168.10.0
192.168.20.0
We need to program 6 more routes:
10.1.1.0
10.1.4.0
10.1.5.0
192.168.30.0
192.168.40.0
172.16.10.0
-----------------------------------------------------------------------------------------------------
R2 has automatically picked up 3 routes that are directly connected:
10.1.4.0
192.168.30.0
192.168.40.0
We need to program 7 more routes:
10.1.1.0
10.1.2.0
10.1.3.0
10.1.5.0
192.168.10.0
192.168.20.0
172.16.10.0
-----------------------------------------------------------------------------------------------------
R3 has automatically picked up 2 routes that are directly connected:
10.1.5.0
172.16.10.0
We need to program 8 more routes:
10.1.1.0
10.1.2.0
10.1.3.0
10.1.4.0
192.168.10.0
192.168.20.0
192.168.30.0
192.168.40.0
Notice the pattern- each router ends up with 10 routes
There are 10 routes total in this topology. AKA ten broadcast domains
Programming the routes
Corp
Corp(config)#
ip route 192.168.10.0 255.255.255.0 10.1.2.2 150
Corp(config)#
ip route 192.168.20.0 255.255.255.0 10.1.3.2 150
Corp(config)#
ip route 192.168.30.0 255.255.255.0 10.1.4.2 150
Corp(config)#
ip route 192.168.40.0 255.255.255.0 10.1.4.2 150
Corp(config)#
ip route 172.16.10.0 255.255.255.0 10.1.5.2 150
Corp(config)#
do show ip route
In the first line, the router is saying that a
classful A network is being subnetted
There are 5 routes directly connected
We see two lines per route (one for the network and one
for the interface(/32)-
10.0.0.0/8 is variably subnetted, 10 subnets, 2 masks
C 10.1.1.0/24 is directly connected, Vlan1
L 10.1.1.1/32 is directly connected, Vlan1
C 10.1.2.0/24 is directly connected, Serial0/0/0
L 10.1.2.1/32 is directly connected, Serial0/0/0
C 10.1.3.0/24 is directly connected, Serial0/0/1
L 10.1.3.1/32 is directly connected, Serial0/0/1
C 10.1.4.0/24 is directly connected, Serial0/1/0
L 10.1.4.1/32 is directly connected, Serial0/1/0
C 10.1.5.0/24 is directly connected, FastEthernet0/0
L 10.1.5.1/32 is directly connected, FastEthernet0/0
and 5 routes that require traversal of a router to reach
172.16.0.0/24 is subnetted, 1 subnets
S 172.16.10.0/24 [150/0] via 10.1.5.2
S 192.168.10.0/24 [150/0] via 10.1.2.2
S 192.168.20.0/24 [150/0] via 10.1.3.2
S 192.168.30.0/24 [150/0] via 10.1.4.2
S 192.168.40.0/24 [150/0] via 10.1.4.2
R1
R1(config)#
ip route 10.1.1.0 255.255.255.0 10.1.2.1 150
R1(config)#
ip route 10.1.4.0 255.255.255.0 10.1.3.1 150
R1(config)#
ip route 10.1.5.0 255.255.255.0 10.1.2.1 150
R1(config)#
ip route 192.168.30.0 255.255.255.0 10.1.3.1 150
R1(config)#
ip route 192.168.40.0 255.255.255.0 10.1.2.1 150
R1(config)#
ip route 172.16.10.0 255.255.255.0 10.1.3.1 150
the only way to get across the corp router is to go into it via 10.1.2.1 or 10.1.3.1
R1(config)#
do show ip route
10.0.0.0/24 is subnetted, 5 subnets
S 10.1.1.0 [150/0] via 10.1.2.1
C 10.1.2.0 is directly connected, Serial0/0/0
C 10.1.3.0 is directly connected, Serial0/0/1
S 10.1.4.0 [150/0] via 10.1.3.1
S 10.1.5.0 [150/0] via 10.1.2.1
172.16.0.0/24 is subnetted, 1 subnets
S 172.16.10.0 [150/0] via 10.1.3.1
C 192.168.10.0/24 is directly connected, FastEthernet0/0
C 192.168.20.0/24 is directly connected, FastEthernet0/1
S 192.168.30.0/24 [150/0] via 10.1.3.1
S 192.168.40.0/24 [150/0] via 10.1.2.1
R2
R2(config)#
iproute 10.1.1.0 255.255.255.0 10.1.4.1 150
R2(config)#
iproute 10.1.2.0 255.255.255.0 10.1.4.1 150
R2(config)#
iproute 10.1.3.0 255.255.255.0 10.1.4.1 150
R2(config)#
iproute 10.1.5.0 255.255.255.0 10.1.4.1 150
R2(config)#
iproute 192.168.10.0 255.255.255.0 10.1.4.1 150
R2(config)#
iproute 192.168.20.0 255.255.255.0 10.1.4.1 150
the only way to get across Corp is to go into it via 10.1.4.1
R2(config)#
do show ip route
10.0.0.0/24 is subnetted, 5 subnets
S 10.1.1.0 [150/0] via 10.1.4.1
S 10.1.2.0 [150/0] via 10.1.4.1
S 10.1.3.0 [150/0] via 10.1.4.1
C 10.1.4.0 is directly connected, Serial0/0/0
S 10.1.5.0 [150/0] via 10.1.4.1
172.16.0.0/24 is subnetted, 1 subnets
S 172.16.10.0 [150/0] via 10.1.4.1
S 192.168.10.0/24 [150/0] via 10.1.4.1
S 192.168.20.0/24 [150/0] via 10.1.4.1
C 192.168.30.0/24 is directly connected, FastEthernet0/0
C 192.168.40.0/24 is directly connected, FastEthernet0/1
R3
R3(config)#
ip route 10.1.1.0 255.255.255.0 fastethernet 0/0 150
R3(config)#
ip route 10.1.2.0 255.255.255.0 fastethernet 0/0 150
R3(config)#
ip route 10.1.3.0 255.255.255.0 fastethernet 0/0 150
R3(config)#
ip route 10.1.4.0 255.255.255.0 fastethernet 0/0 150
R3(config)#
ip route 192.168.10.0 255.255.255.0 fastethernet 0/0 150
R3(config)#
ip route 192.168.20.0 255.255.255.0 fastethernet 0/0 150
R3(config)#
ip route 192.168.30.0 255.255.255.0 fastethernet 0/0 150
R3(config)#
ip route 192.168.40.0 255.255.255.0 fastethernet 0/0 150
the only way to get across Corp is to EXIT R3 via F0/0
R3(config)#
do show ip route
10.0.0.0/8 is variably subnetted, 6 subnets, 2 masks
S 10.1.1.0/24 is directly connected, FastEthernet0/0
S 10.1.2.0/24 is directly connected, FastEthernet0/0
S 10.1.3.0/24 is directly connected, FastEthernet0/0
S 10.1.4.0/24 is directly connected, FastEthernet0/0
C 10.1.5.0/24 is directly connected, FastEthernet0/0
L 10.1.5.2/32 is directly connected, FastEthernet0/0
172.16.0.0/16 is variably subnetted, 2 subnets, 2 masks
C 172.16.10.0/24 is directly connected, Dot11Radio0/0/0
L 172.16.10.1/32 is directly connected, Dot11Radio0/0/0
S 192.168.10.0/24 is directly connected, FastEthernet0/0
S 192.168.20.0/24 is directly connected, FastEthernet0/0
S 192.168.30.0/24 is directly connected, FastEthernet0/0
S 192.168.40.0/24 is directly connected, FastEthernet0/0
before verifying connectivity across the network, we need to make sure all of our hosts are set. The book is giving us the IP addresses for the servers:
Server Gateway 10.1.1.1
ServerWeb 10.1.1.2
ServerEmail 10.1.1.3
ServerDNS 10.1.1.4
Now we can do some testing across the network:
R3#
ping 10.1.2.2
traverse Corp to R1
R3#
ping 10.1.1.1
traverse Corp to a Corp interface we arent directly connected to
R3#
ping 10.1.1.2
traverse Corp to Web server
R3#
ping 10.1.1.3
traverse Corp to Email server
R3#
ping 10.1.1.4
traverse Corp to DNS server
MobileUser
ping 192.168.10.2
traverse R3, Corp, R1 to Finance client
MobileUser
tracert 192.168.10.2
traverse R3, Corp, R1 to Finance client
Tracing route to 192.168.10.2 over a maximum of 30 hops:
1 19 ms 5 ms 20 ms 172.16.10.1
2 20 ms 6 ms 11 ms 10.1.5.1
3 11 ms 15 ms 10 ms 10.1.3.2
4 9 ms 13 ms 22 ms 192.168.10.2
Trace complete.
notice how the trace doesnt count an egress as a hop, only an ingress
ALSO NOTE that tracert is a Windows command.
the IOS equivalent is traceroute
notice how the output differs from the Windows command
R3
traceroute 192.168.10.2
Type escape sequence to abort.
Tracing the route to 192.168.10.2
1 10.1.5.1 0 msec 0 msec 0 msec
2 10.1.2.2 6 msec 0 msec 5 msec
3 192.168.10.2 1 msec 4 msec 3 msec
Default Routing
we could have done this on R3
R3(config)#
ip route 0.0.0.0 0.0.0.0 10.1.5.1
as an alternative to this configuration on R3
R3(config)#
ip route 10.1.1.0 255.255.255.0 fastethernet 0/0 150
R3(config)#
ip route 10.1.2.0 255.255.255.0 fastethernet 0/0 150
R3(config)#
ip route 10.1.3.0 255.255.255.0 fastethernet 0/0 150
R3(config)#
ip route 10.1.4.0 255.255.255.0 fastethernet 0/0 150
R3(config)#
ip route 192.168.10.0 255.255.255.0 fastethernet 0/0 150
R3(config)#
ip route 192.168.20.0 255.255.255.0 fastethernet 0/0 150
R3(config)#
ip route 192.168.30.0 255.255.255.0 fastethernet 0/0 150
R3(config)#
ip route 192.168.40.0 255.255.255.0 fastethernet 0/0 150
the only way to get across Corp is to EXIT R3 via F0/0
This is called default routing. It should only be used on 'stub routers'- those with only one exit path out of the network.
if you try to put a default route on a non-stub router, you could create loops, since there will be more than one path to other routers...
Think of a default route as a static route that uses a wildcard address and mask. The wildcard is 0.0.0.0
to further analyze this comparison, I'm going to remove the routes from R3...
R3(config)#
no ip route 10.1.1.0 255.255.255.0 fastethernet0/0 150
R3(config)#
no ip route 10.1.2.0 255.255.255.0 fastethernet0/0 150
R3(config)#
no ip route 10.1.3.0 255.255.255.0 fastethernet0/0 150
R3(config)#
no ip route 10.1.4.0 255.255.255.0 fastethernet0/0 150
R3(config)#
no ip route 192.168.10.0 255.255.255.0 fastethernet0/0 150
R3(config)#
no ip route 192.168.20.0 255.255.255.0 fastethernet0/0 150
R3(config)#
no ip route 192.168.30.0 255.255.255.0 fastethernet0/0 150
R3(config)#
no ip route 192.168.40.0 255.255.255.0 fastethernet0/0 150
and then set the default route instead.
R3#
ip route 0.0.0.0 0.0.0.0 10.1.5.1 --- ingress at next hop
OR
R3#
ip route 0.0.0.0 0.0.0.0 Fa0/0 --- egress interface
Then compare the output of show ip route
static routes set
R3#
show ip route
Gateway of last resort is not set
10.0.0.0/8 is variably subnetted, 6 subnets, 2 masks
S 10.1.1.0/24 is directly connected, FastEthernet0/0
S 10.1.2.0/24 is directly connected, FastEthernet0/0
S 10.1.3.0/24 is directly connected, FastEthernet0/0
S 10.1.4.0/24 is directly connected, FastEthernet0/0
C 10.1.5.0/24 is directly connected, FastEthernet0/0
L 10.1.5.2/32 is directly connected, FastEthernet0/0
172.16.0.0/16 is variably subnetted, 2 subnets, 2 masks
C 172.16.10.0/24 is directly connected, Dot11Radio0/0/0
L 172.16.10.1/32 is directly connected, Dot11Radio0/0/0
S 192.168.10.0/24 is directly connected, FastEthernet0/0
S 192.168.20.0/24 is directly connected, FastEthernet0/0
S 192.168.30.0/24 is directly connected, FastEthernet0/0
S 192.168.40.0/24 is directly connected, FastEthernet0/0
default route set
R3#
show ip route
Gateway of last resort is 10.1.5.1 to network 0.0.0.0
10.0.0.0/8 is variably subnetted, 2 subnets, 2 masks
C 10.1.5.0/24 is directly connected, FastEthernet0/0
L 10.1.5.2/32 is directly connected, FastEthernet0/0
172.16.0.0/16 is variably subnetted, 2 subnets, 2 masks
C 172.16.10.0/24 is directly connected, Dot11Radio0/0/0
L 172.16.10.1/32 is directly connected, Dot11Radio0/0/0
S* 0.0.0.0/0 [1/0] via 10.1.5.1
two directly connected networks- 10.1.5.0 and 172.16.10.0
anything not included in those networks goes to ingress of attached neighbor Corp 10.1.5.1
in this toplogy, that includes:
192.168.10.0
192.168.20.0
192.168.30.0
192.168.40.0
and
10.1.1.0
10.1.2.0
10.1.3.0
10.1.4.0
RIP Routing Information Protocol
R1(config)#
router ?
bgp Border Gateway Protocol (BGP)
eigrp Enhanced Interior Gateway Routing Protocol (EIGRP)
ospf Open Shortest Path First (OSPF)
rip Routing Information Protocol (RIP)
set RIP on Corp
Corp(config)#
router rip
Corp(config-router)#
network 10.0.0.0
set RIP on R1
R1(config)#
router rip
R1(config-router)#
network 10.0.0.0
R1 routing table
R1(config)#
do show ip route
10.0.0.0/24 is subnetted, 5 subnets
R 10.1.1.0 [120/1] via 10.1.2.1, 00:00:21, Serial0/0/0
[120/1] via 10.1.3.1, 00:00:21, Serial0/0/1
C 10.1.2.0 is directly connected, Serial0/0/0
C 10.1.3.0 is directly connected, Serial0/0/1
R 10.1.4.0 [120/1] via 10.1.2.1, 00:00:21, Serial0/0/0
[120/1] via 10.1.3.1, 00:00:21, Serial0/0/1
R 10.1.5.0 [120/1] via 10.1.2.1, 00:00:21, Serial0/0/0
[120/1] via 10.1.3.1, 00:00:21, Serial0/0/1
172.16.0.0/24 is subnetted, 1 subnets
S 172.16.10.0 [150/0] via 10.1.3.1
C 192.168.10.0/24 is directly connected, FastEthernet0/0
C 192.168.20.0/24 is directly connected, FastEthernet0/1
S 192.168.30.0/24 [150/0] via 10.1.3.1
S 192.168.40.0/24 [150/0] via 10.1.2.1
here's R1 before RIP, with only static routes set:
R1(config)#
do show ip route
10.0.0.0/24 is subnetted, 5 subnets
S 10.1.1.0 [150/0] via 10.1.2.1
C 10.1.2.0 is directly connected, Serial0/0/0
C 10.1.3.0 is directly connected, Serial0/0/1
S 10.1.4.0 [150/0] via 10.1.3.1
S 10.1.5.0 [150/0] via 10.1.2.1
172.16.0.0/24 is subnetted, 1 subnets
S 172.16.10.0 [150/0] via 10.1.3.1
C 192.168.10.0/24 is directly connected, FastEthernet0/0
C 192.168.20.0/24 is directly connected, FastEthernet0/1
S 192.168.30.0/24 [150/0] via 10.1.3.1
S 192.168.40.0/24 [150/0] via 10.1.2.1
These RIP routes are being advertised as available *to other RIP routers*.
CORP is advertisting THREE routes via RIP to R1 right now
10.1.1.0
10.1.4.0
10.1.5.0
access to those networks can be achieved by R1 by going THROUGH CORP via ingress .2.1 or .3.1
The advantage..... is that we didnt statically program these routes
we engaged RIP, on BOTH routers- R1 and Corp, and handed them BOTH the network "10.0.0.0"
So, why did RIP choose to display these particular routes
Keep in mind that the output above is from R1 only... In the context of the R1 ROUTER ONLY,
there are three relevant routes within the "10.0.0.0" parameter we specified. The three routes involve Corp.
Corp is sending RIP data about these routes to Corp.
Lets look closer at how this is happening:
here's our starting point before any RIP is set
here's our routing tables after i set RIP with 10.0.0.0 on both..
FIRST i set it on Corp, then R1.(per the book's instructions) As a result we are seeing RIP routes in R1 only....
then I went back to a fresh packet tracer file with no RIP set. And I set RIP in the opposite order;
FIRST i set it on R1, then Corp. And again, we are seeing RIP routes in R1 only....
I wanted to prove that it didnt matter which order we enabled RIP on the two routers. What matters here is that
we enable RIP on both of them with the criteria of 10.0.0.0
Recall the topology:
if Corp and R1 are set for RIP and given the criteria 10.0.0.0, meaning that we are trying to reach networks
within that range, then it follows that Corp will advertise 1.1.0, 1.4.0, and 1.5.0 to R1, because Corp stands between those networks
and R1
"Hi R1, I'm Corp I have three networks that fall inside 10.0.0.0, and you can reach them through me via .2.1 or .3.1"
It also follows that Corp's routing table shows no RIP routes- because R1 isnt advertising any. R1 doesnt have any networks
in the 10.0.0.0 range that Corp could reach
To further clarify this, we'll proceed with the book's instructions. We'll now set more RIP routes on R1
R1(config)#
router rip
R1(config-router)#
network 192.168.10.0
R1(config-router)#
network 192.168.20.0
Corp routing table before RIP set on R1:
Corp#
show ip route
10.0.0.0/8 is variably subnetted, 10 subnets, 2 masks
C 10.1.1.0/24 is directly connected, Vlan1
L 10.1.1.1/32 is directly connected, Vlan1
C 10.1.2.0/24 is directly connected, Serial0/0/0
L 10.1.2.1/32 is directly connected, Serial0/0/0
C 10.1.3.0/24 is directly connected, Serial0/0/1
L 10.1.3.1/32 is directly connected, Serial0/0/1
C 10.1.4.0/24 is directly connected, Serial0/1/0
L 10.1.4.1/32 is directly connected, Serial0/1/0
C 10.1.5.0/24 is directly connected, FastEthernet0/0
L 10.1.5.1/32 is directly connected, FastEthernet0/0
172.16.0.0/24 is subnetted, 1 subnets
S 172.16.10.0/24 [150/0] via 10.1.5.2
S 192.168.10.0/24 [150/0] via 10.1.2.2
S 192.168.20.0/24 [150/0] via 10.1.3.2
S 192.168.30.0/24 [150/0] via 10.1.4.2
S 192.168.40.0/24 [150/0] via 10.1.4.2
Corp routing table after RIP set on R1:
Gateway of last resort is not set
10.0.0.0/8 is variably subnetted, 10 subnets, 2 masks
C 10.1.1.0/24 is directly connected, Vlan1
L 10.1.1.1/32 is directly connected, Vlan1
C 10.1.2.0/24 is directly connected, Serial0/0/0
L 10.1.2.1/32 is directly connected, Serial0/0/0
C 10.1.3.0/24 is directly connected, Serial0/0/1
L 10.1.3.1/32 is directly connected, Serial0/0/1
C 10.1.4.0/24 is directly connected, Serial0/1/0
L 10.1.4.1/32 is directly connected, Serial0/1/0
C 10.1.5.0/24 is directly connected, FastEthernet0/0
L 10.1.5.1/32 is directly connected, FastEthernet0/0
nothing changed so far
172.16.0.0/24 is subnetted, 1 subnets
S 172.16.10.0/24 [150/0] via 10.1.5.2
no change
R 192.168.10.0/24 [120/1] via 10.1.2.2, 00:00:08, Serial0/0/0
[120/1] via 10.1.3.2, 00:00:08, Serial0/0/1
RIP overrides static- 2 paths available now
R 192.168.20.0/24 [120/1] via 10.1.2.2, 00:00:08, Serial0/0/0
[120/1] via 10.1.3.2, 00:00:08, Serial0/0/1
RIP overrides static- 2 paths available now
S 192.168.30.0/24 [150/0] via 10.1.4.2
no change
S 192.168.40.0/24 [150/0] via 10.1.4.2
no change
"Hi Corp- I'm R1 and I have zero networks
that fall inside 10.0.0.0, however I do have some networks that fall within
192.168.20.0 and 192.168.10.0
and you can reach them through me(R1) if you ingress at .1.2.2 or .1.3.2"
ok, we have the concept down. Time to proceed and set up RIP on R2............
R2(config)#
router rip
R2(config-router)#
network 10.0.0.0
R2(config-router)#
network 192.168.30.0
R2(config-router)#
network 192.168.40.0
R2 before RIP enabled
R2#
show ip route
10.0.0.0/24 is subnetted, 5 subnets
S 10.1.1.0 [150/0] via 10.1.4.1
S 10.1.2.0 [150/0] via 10.1.4.1
S 10.1.3.0 [150/0] via 10.1.4.1
C 10.1.4.0 is directly connected, Serial0/0/0
S 10.1.5.0 [150/0] via 10.1.4.1
172.16.0.0/24 is subnetted, 1 subnets
S 172.16.10.0 [150/0] via 10.1.4.1
S 192.168.10.0/24 [150/0] via 10.1.4.1
S 192.168.20.0/24 [150/0] via 10.1.4.1
C 192.168.30.0/24 is directly connected, FastEthernet0/0
C 192.168.40.0/24 is directly connected, FastEthernet0/1
R2 after RIP added
R2#
show ip route
10.0.0.0/24 is subnetted, 5 subnets
R 10.1.1.0 [120/1] via 10.1.4.1, 00:00:24, Serial0/0/0
from corp
R 10.1.2.0 [120/1] via 10.1.4.1, 00:00:24, Serial0/0/0
from corp
R 10.1.3.0 [120/1] via 10.1.4.1, 00:00:24, Serial0/0/0
from corp
C 10.1.4.0 is directly connected, Serial0/0/0
R 10.1.5.0 [120/1] via 10.1.4.1, 00:00:24, Serial0/0/0
from corp
172.16.0.0/24 is subnetted, 1 subnets
S 172.16.10.0 [150/0] via 10.1.4.1
R 192.168.10.0/24 [120/2] via 10.1.4.1, 00:00:24, Serial0/0/0
from R1 via corp
R 192.168.20.0/24 [120/2] via 10.1.4.1, 00:00:24, Serial0/0/0
from R1 via corp
C 192.168.30.0/24 is directly connected, FastEthernet0/0
C 192.168.40.0/24 is directly connected, FastEthernet0/1
now lets compare the Corp and R1 routing tables- before RIP was set on R2 and after
Corp before R2 RIP
Corp#
show ip route
10.0.0.0/8 is variably subnetted, 10 subnets, 2 masks
C 10.1.1.0/24 is directly connected, Vlan1
L 10.1.1.1/32 is directly connected, Vlan1
C 10.1.2.0/24 is directly connected, Serial0/0/0
L 10.1.2.1/32 is directly connected, Serial0/0/0
C 10.1.3.0/24 is directly connected, Serial0/0/1
L 10.1.3.1/32 is directly connected, Serial0/0/1
C 10.1.4.0/24 is directly connected, Serial0/1/0
L 10.1.4.1/32 is directly connected, Serial0/1/0
C 10.1.5.0/24 is directly connected, FastEthernet0/0
L 10.1.5.1/32 is directly connected, FastEthernet0/0
172.16.0.0/24 is subnetted, 1 subnets
S 172.16.10.0/24 [150/0] via 10.1.5.2
R 192.168.10.0/24 [120/1] via 10.1.2.2, 00:00:02, Serial0/0/0
[120/1] via 10.1.3.2, 00:00:02, Serial0/0/1
R 192.168.20.0/24 [120/1] via 10.1.2.2, 00:00:02, Serial0/0/0
[120/1] via 10.1.3.2, 00:00:02, Serial0/0/1
from R1
S 192.168.30.0/24 [150/0] via 10.1.4.2
S 192.168.40.0/24 [150/0] via 10.1.4.2
Corp after R2 RIP
Corp#
show ip route
10.0.0.0/8 is variably subnetted, 10 subnets, 2 masks
C 10.1.1.0/24 is directly connected, Vlan1
L 10.1.1.1/32 is directly connected, Vlan1
C 10.1.2.0/24 is directly connected, Serial0/0/0
L 10.1.2.1/32 is directly connected, Serial0/0/0
C 10.1.3.0/24 is directly connected, Serial0/0/1
L 10.1.3.1/32 is directly connected, Serial0/0/1
C 10.1.4.0/24 is directly connected, Serial0/1/0
L 10.1.4.1/32 is directly connected, Serial0/1/0
C 10.1.5.0/24 is directly connected, FastEthernet0/0
L 10.1.5.1/32 is directly connected, FastEthernet0/0
172.16.0.0/24 is subnetted, 1 subnets
S 172.16.10.0/24 [150/0] via 10.1.5.2
R 192.168.10.0/24 [120/1] via 10.1.2.2, 00:00:19, Serial0/0/0
[120/1] via 10.1.3.2, 00:00:19, Serial0/0/1
R 192.168.20.0/24 [120/1] via 10.1.2.2, 00:00:19, Serial0/0/0
[120/1] via 10.1.3.2, 00:00:19, Serial0/0/1
from R1
R 192.168.30.0/24 [120/1] via 10.1.4.2, 00:00:15, Serial0/1/0
R 192.168.40.0/24 [120/1] via 10.1.4.2, 00:00:15, Serial0/1/0
from R2
RIP on R2 is advertising .30.0 and .40.0 to Corp
R1 before R2 RIP
R1#
show ip route
10.0.0.0/24 is subnetted, 5 subnets
R 10.1.1.0 [120/1] via 10.1.2.1, 00:00:05, Serial0/0/0
[120/1] via 10.1.3.1, 00:00:05, Serial0/0/1
from Corp
C 10.1.2.0 is directly connected, Serial0/0/0
C 10.1.3.0 is directly connected, Serial0/0/1
R 10.1.4.0 [120/1] via 10.1.2.1, 00:00:05, Serial0/0/0
[120/1] via 10.1.3.1, 00:00:05, Serial0/0/1
R 10.1.5.0 [120/1] via 10.1.2.1, 00:00:05, Serial0/0/0
[120/1] via 10.1.3.1, 00:00:05, Serial0/0/1
from Corp
172.16.0.0/24 is subnetted, 1 subnets
S 172.16.10.0 [150/0] via 10.1.3.1
C 192.168.10.0/24 is directly connected, FastEthernet0/0
C 192.168.20.0/24 is directly connected, FastEthernet0/1
S 192.168.30.0/24 [150/0] via 10.1.3.1
S 192.168.40.0/24 [150/0] via 10.1.2.1
R1 after R2 RIP
R1#
show ip route
10.0.0.0/24 is subnetted, 5 subnets
R 10.1.1.0 [120/1] via 10.1.2.1, 00:00:06, Serial0/0/0
[120/1] via 10.1.3.1, 00:00:06, Serial0/0/1
from Corp
C 10.1.2.0 is directly connected, Serial0/0/0
C 10.1.3.0 is directly connected, Serial0/0/1
R 10.1.4.0 [120/1] via 10.1.2.1, 00:00:06, Serial0/0/0
[120/1] via 10.1.3.1, 00:00:06, Serial0/0/1
R 10.1.5.0 [120/1] via 10.1.2.1, 00:00:06, Serial0/0/0
[120/1] via 10.1.3.1, 00:00:06, Serial0/0/1
from Corp
172.16.0.0/24 is subnetted, 1 subnets
S 172.16.10.0 [150/0] via 10.1.3.1
C 192.168.10.0/24 is directly connected, FastEthernet0/0
C 192.168.20.0/24 is directly connected, FastEthernet0/1
R 192.168.30.0/24 [120/2] via 10.1.3.1, 00:00:06, Serial0/0/1
[120/2] via 10.1.2.1, 00:00:06, Serial0/0/0
R 192.168.40.0/24 [120/2] via 10.1.2.1, 00:00:06, Serial0/0/0
[120/2] via 10.1.3.1, 00:00:06, Serial0/0/1
from R2 via Corp
Now to set RIP on R3
R3(config)#
router rip
R3(config-router)#
network 10.0.0.0
R3(config-router)#
network 172.16.0.0
note that R3 is our only router with "gateway of last resort" set because we set a default route instead of static routes
As a result, we only see directly connected routes listed, along with a single "S*" for the default gateway
R3 before RIP
R3#
show ip route
Gateway of last resort is 10.1.5.1 to network 0.0.0.0
10.0.0.0/8 is variably subnetted, 2 subnets, 2 masks
C 10.1.5.0/24 is directly connected, FastEthernet0/0
L 10.1.5.2/32 is directly connected, FastEthernet0/0
172.16.0.0/16 is variably subnetted, 2 subnets, 2 masks
C 172.16.10.0/24 is directly connected, Dot11Radio0/0/0
L 172.16.10.1/32 is directly connected, Dot11Radio0/0/0
S* 0.0.0.0/0 [1/0] via 10.1.5.1
R3 after RIP
R3#
show ip route
Gateway of last resort is 10.1.5.1 to network 0.0.0.0
-------------------------------------------------------------
10.0.0.0/8 is variably subnetted, 6 subnets, 2 masks
R 10.1.1.0/24 [120/1] via 10.1.5.1, 00:00:21, FastEthernet0/0
R 10.1.2.0/24 [120/1] via 10.1.5.1, 00:00:21, FastEthernet0/0
R 10.1.3.0/24 [120/1] via 10.1.5.1, 00:00:21, FastEthernet0/0
R 10.1.4.0/24 [120/1] via 10.1.5.1, 00:00:21, FastEthernet0/0
from Corp
C 10.1.5.0/24 is directly connected, FastEthernet0/0
L 10.1.5.2/32 is directly connected, FastEthernet0/0
-------------------------------------------------------------
172.16.0.0/16 is variably subnetted, 2 subnets, 2 masks
C 172.16.10.0/24 is directly connected, Dot11Radio0/0/0
L 172.16.10.1/32 is directly connected, Dot11Radio0/0/0
R 192.168.10.0/24 [120/2] via 10.1.5.1, 00:00:21, FastEthernet0/0
R 192.168.20.0/24 [120/2] via 10.1.5.1, 00:00:21, FastEthernet0/0
From R1 via Corp
R 192.168.30.0/24 [120/2] via 10.1.5.1, 00:00:21, FastEthernet0/0
R 192.168.40.0/24 [120/2] via 10.1.5.1, 00:00:21, FastEthernet0/0
From R2 via Corp
S* 0.0.0.0/0 [1/0] via 10.1.5.1
Corp before R3 RIP
Corp#
show ip route
10.0.0.0/8 is variably subnetted, 10 subnets, 2 masks
C 10.1.1.0/24 is directly connected, Vlan1
L 10.1.1.1/32 is directly connected, Vlan1
C 10.1.2.0/24 is directly connected, Serial0/0/0
L 10.1.2.1/32 is directly connected, Serial0/0/0
C 10.1.3.0/24 is directly connected, Serial0/0/1
L 10.1.3.1/32 is directly connected, Serial0/0/1
C 10.1.4.0/24 is directly connected, Serial0/1/0
L 10.1.4.1/32 is directly connected, Serial0/1/0
C 10.1.5.0/24 is directly connected, FastEthernet0/0
L 10.1.5.1/32 is directly connected, FastEthernet0/0
172.16.0.0/24 is subnetted, 1 subnets
S 172.16.10.0/24 [150/0] via 10.1.5.2
R 192.168.10.0/24 [120/1] via 10.1.2.2, 00:00:26, Serial0/0/0
[120/1] via 10.1.3.2, 00:00:26, Serial0/0/1
R 192.168.20.0/24 [120/1] via 10.1.2.2, 00:00:26, Serial0/0/0
[120/1] via 10.1.3.2, 00:00:26, Serial0/0/1
from R1 via corp
R 192.168.30.0/24 [120/1] via 10.1.4.2, 00:00:21, Serial0/1/0
R 192.168.40.0/24 [120/1] via 10.1.4.2, 00:00:21, Serial0/1/0
from R2 via corp
Corp after R3 RIP
Corp#
show ip route
10.0.0.0/8 is variably subnetted, 10 subnets, 2 masks
C 10.1.1.0/24 is directly connected, Vlan1
L 10.1.1.1/32 is directly connected, Vlan1
C 10.1.2.0/24 is directly connected, Serial0/0/0
L 10.1.2.1/32 is directly connected, Serial0/0/0
C 10.1.3.0/24 is directly connected, Serial0/0/1
L 10.1.3.1/32 is directly connected, Serial0/0/1
C 10.1.4.0/24 is directly connected, Serial0/1/0
L 10.1.4.1/32 is directly connected, Serial0/1/0
C 10.1.5.0/24 is directly connected, FastEthernet0/0
L 10.1.5.1/32 is directly connected, FastEthernet0/0
172.16.0.0/16 is variably subnetted, 2 subnets, 2 masks
R 172.16.0.0/16 [120/1] via 10.1.5.2, 00:00:13, FastEthernet0/0
S 172.16.10.0/24 [150/0] via 10.1.5.2
from R3
R 192.168.10.0/24 [120/1] via 10.1.3.2, 00:00:13, Serial0/0/1
[120/1] via 10.1.2.2, 00:00:13, Serial0/0/0
R 192.168.20.0/24 [120/1] via 10.1.3.2, 00:00:13, Serial0/0/1
[120/1] via 10.1.2.2, 00:00:13, Serial0/0/0
from R1 via corp
R 192.168.30.0/24 [120/1] via 10.1.4.2, 00:00:24, Serial0/1/0
R 192.168.40.0/24 [120/1] via 10.1.4.2, 00:00:24, Serial0/1/0
from R2 via corp
R2 before R3 RIP
R2#
show ip route
10.0.0.0/24 is subnetted, 5 subnets
R 10.1.1.0 [120/1] via 10.1.4.1, 00:00:15, Serial0/0/0
R 10.1.2.0 [120/1] via 10.1.4.1, 00:00:15, Serial0/0/0
R 10.1.3.0 [120/1] via 10.1.4.1, 00:00:15, Serial0/0/0
from Corp
C 10.1.4.0 is directly connected, Serial0/0/0
R 10.1.5.0 [120/1] via 10.1.4.1, 00:00:15, Serial0/0/0
from Corp
172.16.0.0/24 is subnetted, 1 subnets
S 172.16.10.0 [150/0] via 10.1.4.1
R 192.168.10.0/24 [120/2] via 10.1.4.1, 00:00:15, Serial0/0/0
R 192.168.20.0/24 [120/2] via 10.1.4.1, 00:00:15, Serial0/0/0
from R1 via Corp
C 192.168.30.0/24 is directly connected, FastEthernet0/0
C 192.168.40.0/24 is directly connected, FastEthernet0/1
R2 after R3 RIP
R2#
show ip route
10.0.0.0/24 is subnetted, 5 subnets
R 10.1.1.0 [120/1] via 10.1.4.1, 00:00:20, Serial0/0/0
R 10.1.2.0 [120/1] via 10.1.4.1, 00:00:20, Serial0/0/0
R 10.1.3.0 [120/1] via 10.1.4.1, 00:00:20, Serial0/0/0
from Corp
C 10.1.4.0 is directly connected, Serial0/0/0
R 10.1.5.0 [120/1] via 10.1.4.1, 00:00:20, Serial0/0/0
from Corp
172.16.0.0/16 is variably subnetted, 2 subnets, 2 masks
R 172.16.0.0/16 [120/2] via 10.1.4.1, 00:00:20, Serial0/0/0
S 172.16.10.0/24 [150/0] via 10.1.4.1
from R3 via Corp
R 192.168.10.0/24 [120/2] via 10.1.4.1, 00:00:20, Serial0/0/0
R 192.168.20.0/24 [120/2] via 10.1.4.1, 00:00:20, Serial0/0/0
from R1 via Corp
C 192.168.30.0/24 is directly connected, FastEthernet0/0
C 192.168.40.0/24 is directly connected, FastEthernet0/1
R1 before R3 RIP
R1#
show ip route
10.0.0.0/24 is subnetted, 5 subnets
R 10.1.1.0 [120/1] via 10.1.2.1, 00:00:04, Serial0/0/0
[120/1] via 10.1.3.1, 00:00:04, Serial0/0/1
C 10.1.2.0 is directly connected, Serial0/0/0
C 10.1.3.0 is directly connected, Serial0/0/1
R 10.1.4.0 [120/1] via 10.1.2.1, 00:00:04, Serial0/0/0
[120/1] via 10.1.3.1, 00:00:04, Serial0/0/1
R 10.1.5.0 [120/1] via 10.1.2.1, 00:00:04, Serial0/0/0
[120/1] via 10.1.3.1, 00:00:04, Serial0/0/1
from Corp
172.16.0.0/24 is subnetted, 1 subnets
S 172.16.10.0 [150/0] via 10.1.3.1
C 192.168.10.0/24 is directly connected, FastEthernet0/0
C 192.168.20.0/24 is directly connected, FastEthernet0/1
R 192.168.30.0/24 [120/2] via 10.1.2.1, 00:00:04, Serial0/0/0
[120/2] via 10.1.3.1, 00:00:04, Serial0/0/1
R 192.168.40.0/24 [120/2] via 10.1.2.1, 00:00:04, Serial0/0/0
[120/2] via 10.1.3.1, 00:00:04, Serial0/0/1
from R2 via Corp
R1 after R3 RIP
R1#
show ip route
10.0.0.0/24 is subnetted, 5 subnets
R 10.1.1.0 [120/1] via 10.1.3.1, 00:00:03, Serial0/0/1
[120/1] via 10.1.2.1, 00:00:03, Serial0/0/0
C 10.1.2.0 is directly connected, Serial0/0/0
C 10.1.3.0 is directly connected, Serial0/0/1
R 10.1.4.0 [120/1] via 10.1.3.1, 00:00:03, Serial0/0/1
[120/1] via 10.1.2.1, 00:00:03, Serial0/0/0
R 10.1.5.0 [120/1] via 10.1.3.1, 00:00:03, Serial0/0/1
[120/1] via 10.1.2.1, 00:00:03, Serial0/0/0
from Corp
172.16.0.0/16 is variably subnetted, 2 subnets, 2 masks
R 172.16.0.0/16 [120/2] via 10.1.3.1, 00:00:03, Serial0/0/1
[120/2] via 10.1.2.1, 00:00:03, Serial0/0/0
S 172.16.10.0/24 [150/0] via 10.1.3.1
from R3 via Corp
C 192.168.10.0/24 is directly connected, FastEthernet0/0
C 192.168.20.0/24 is directly connected, FastEthernet0/1
R 192.168.30.0/24 [120/2] via 10.1.3.1, 00:00:03, Serial0/0/1
[120/2] via 10.1.2.1, 00:00:03, Serial0/0/0
R 192.168.40.0/24 [120/2] via 10.1.3.1, 00:00:03, Serial0/0/1
[120/2] via 10.1.2.1, 00:00:03, Serial0/0/0
from R2 via Corp
Verifying Configurations
in addition to
show ip route
we can also use
show ip protocols
and
debug rip ip
Corp#
show ip protocols
Routing Protocol is "rip"
Sending updates every 30 seconds, next due in 11 seconds
Invalid after 180 seconds, hold down 180, flushed after 240
Outgoing update filter list for all interfaces is not set
Incoming update filter list for all interfaces is not set
Redistributing: rip
Default version control: send version 1, receive any version
Interface Send Recv Triggered RIP Key-chain
Vlan1 1 2 1
FastEthernet0/0 1 2 1
Serial0/0/1 1 2 1
Serial0/1/0 1 2 1
Serial0/0/0 1 2 1
Automatic network summarization is in effect
Maximum path: 4
Routing for Networks:
10.0.0.0
Passive Interface(s):
Routing Information Sources:
Gateway Distance Last Update
10.1.5.2 120 00:00:00
10.1.3.2 120 00:00:10
10.1.2.2 120 00:00:10
10.1.4.2 120 00:00:20
Distance: (default is 120)
R3#
debug ip rip
R3#RIP: received v1 update from 10.1.5.1 on FastEthernet0/0
10.1.1.0 in 1 hops
10.1.2.0 in 1 hops
10.1.3.0 in 1 hops
10.1.4.0 in 1 hops
192.168.10.0 in 2 hops
192.168.20.0 in 2 hops
192.168.30.0 in 2 hops
192.168.40.0 in 2 hops
R3#RIP: sending v1 update to 255.255.255.255 via Dot11Radio0/0/0 (172.16.10.1)
RIP: build update entries
network 10.0.0.0 metric 1
network 192.168.10.0 metric 3
network 192.168.20.0 metric 3
network 192.168.30.0 metric 3
network 192.168.40.0 metric 3
RIP: sending v1 update to 255.255.255.255 via FastEthernet0/0 (10.1.5.2)
RIP: build update entries
network 172.16.0.0 metric 1
output loops until manually disabled..............
R3#
undebug all
All possible debugging has been turned off
Note that due to the Split Horizon rule, R3 is not sending all of it's known RIP data to Corp.
It is sending all known RIP data out of the wifi interface (even there though there's no router that way),
but it is ONLY sending data about the wifi network back to Corp; data that Corp doesnt already have
Now lets look at some examples with sample routers..
I got hung up on these two examples because I found the
wording to be a bit confusing. Also there was subnetting involved that I was able to figure out, but threw me at first
First source of confusion- we have two seperate examples, and I was mixing them up.
The examples are:
Use the debug ip rip command to both:
discover a problem
and figure out how RIP was configured on a router from a different sample network
The conclusion regarding 'figuring out how RIP is configured' on this router, is that RIP networks are set as 10.0.0.0 and 172.16.0.0.
We determined that we are not the 'first source' of info on the 192.168.1.0 nertwork, since it is a metric of 2. We are sending out RIP data on that network,
but that RIP data is made availbale to us via another router.
I also got tripped up on the fact that RA is sending out S0/0 which corresponds 10.0.8.1,
and then receiving on the same interface S0/0 from an ip address of 10.0.15.0 on the other side of the link
I was able to determine that these two address are actually on the same subnet. My initial assumption was that the network address for the link is 10.0.0.0.
The problem doesn't give the subnet mask- I guessed it as /20 by using a 16 block since we can see that the third octet seems to move in 8's
if the network starts at 10.0.0.0 and we use /20 with 16 block, we would indeed have a last host address of 10.0.15.254, so 10.0.15.2 would be a valid host.
So there was a twist to this problem which needed subnetting to solve. It wasnt particulary releveant to the subject of RIP, but I was curious why the address on
the other side of that link looked so strange.
The problem also points out that we can determine there are 'at least' two routers participating in RIP here since we are sending RIP data out two interfaces but
only receiving RIP data on one interface. I'm unclear on why its worded this way; we know we are a RIP router- the fact that we are receiving data on one interface
would suggest there is 'at least one more' RIP router out there.
that's it for this example. Back to the original statement-
Use the debug ip rip command to both discover a problem and figure out
how RIP was configured on a router from a different sample network
We just 'figured out how RIP was configured on a router'.. The second example is regarding 'discovering a problem', although it is mentioned first.
The second example will use debug ip rip and show ip route to find a problem with the network
it looks like RIP data for 172.16.20.0 was received on S0/0, and then that interface was bumped out of the routing table entry for that network in favor of a static route.
ok, moving on now to RIP V2
RIP V2
enable it on all four routers
Corp(config)
router rip
Corp(config-router)
version 2
R1(config)
router rip
R1(config-router)
version 2
R2(config)
router rip
R2(config-router)
version 2
R3(config)
router rip
R3(config-router)
version 2
We'll use R1 to compare RIPv1 and RIPv2
RIPv1
R1(config)
debug ip rip
R1#RIP: sending v1 update to 255.255.255.255 via FastEthernet0/0 (192.168.10.1)
RIP: build update entries
network 10.0.0.0 metric 1
network 172.16.0.0 metric 3
network 192.168.20.0 metric 1
network 192.168.30.0 metric 3
network 192.168.40.0 metric 3
RIP: sending v1 update to 255.255.255.255 via FastEthernet0/1 (192.168.20.1)
RIP: build update entries
network 10.0.0.0 metric 1
network 172.16.0.0 metric 3
network 192.168.10.0 metric 1
network 192.168.30.0 metric 3
network 192.168.40.0 metric 3
RIP: sending v1 update to 255.255.255.255 via Serial0/0/0 (10.1.2.2)
RIP: build update entries
network 10.1.3.0 metric 1
network 192.168.10.0 metric 1
network 192.168.20.0 metric 1
RIP: sending v1 update to 255.255.255.255 via Serial0/0/1 (10.1.3.2)
RIP: build update entries
network 10.1.2.0 metric 1
network 192.168.10.0 metric 1
network 192.168.20.0 metric 1
RIPv2
R1(config)
debug ip rip
R1#RIP: sending v2 update to 224.0.0.9 via FastEthernet0/0 (192.168.10.1)
RIP: build update entries
10.0.0.0/8 via 0.0.0.0, metric 1, tag 0
172.16.0.0/16 via 0.0.0.0, metric 3, tag 0
192.168.20.0/24 via 0.0.0.0, metric 1, tag 0
192.168.30.0/24 via 0.0.0.0, metric 3, tag 0
192.168.40.0/24 via 0.0.0.0, metric 3, tag 0
RIP: sending v2 update to 224.0.0.9 via FastEthernet0/1 (192.168.20.1)
RIP: build update entries
10.0.0.0/8 via 0.0.0.0, metric 1, tag 0
172.16.0.0/16 via 0.0.0.0, metric 3, tag 0
192.168.10.0/24 via 0.0.0.0, metric 1, tag 0
192.168.30.0/24 via 0.0.0.0, metric 3, tag 0
192.168.40.0/24 via 0.0.0.0, metric 3, tag 0
RIP: sending v2 update to 224.0.0.9 via Serial0/0/0 (10.1.2.2)
RIP: build update entries
10.1.3.0/24 via 0.0.0.0, metric 1, tag 0
192.168.10.0/24 via 0.0.0.0, metric 1, tag 0
192.168.20.0/24 via 0.0.0.0, metric 1, tag 0
RIP: sending v2 update to 224.0.0.9 via Serial0/0/1 (10.1.3.2)
RIP: build update entries
10.1.2.0/24 via 0.0.0.0, metric 1, tag 0
192.168.10.0/24 via 0.0.0.0, metric 1, tag 0
192.168.20.0/24 via 0.0.0.0, metric 1, tag 0
R1(config)
show ip protocols
Routing Protocol is "rip"
Sending updates every 30 seconds, next due in 13 seconds
Invalid after 180 seconds, hold down 180, flushed after 240
Outgoing update filter list for all interfaces is not set
Incoming update filter list for all interfaces is not set
Redistributing: rip
Default version control: send version 2, receive 2
Interface Send Recv Triggered RIP Key-chain
FastEthernet0/0 2 2
FastEthernet0/1 2 2
Serial0/0/0 2 2
Serial0/0/1 2 2
Automatic network summarization is in effect
Maximum path: 4
Routing for Networks:
10.0.0.0
192.168.10.0
192.168.20.0
Passive Interface(s):
Routing Information Sources:
Gateway Distance Last Update
10.1.3.1 120 00:00:21
10.1.2.1 120 00:00:21
Distance: (default is 120)
final task of this chapter
Enable a default route out to the internet , and advertise via RIP
R3(config)#
interface s0/1/0 (this is only for example, so I am not adding a serial card to R3)
R3(config-if)#
ip addr 172.16.10.5 255.255.255.252
R3(config-if)#
exit
R3(config)#
ip route 0.0.0.0 0.0.0.0 s0/0
R3(config)#
ip default-network 172.16.0.0 tells other routers via RIP that default WAN route is through R3
Chapter 8 Exam Essentials IP Routing
1. Describe the Basic IP routing process
frame changes at each hop, but packet doesnt change EXCEPT that the TTL field in the IP header decrements
2. List the information required by a router to successfully route packets
destination IP address, location of other routers, possible routers to all remote networks,
the best route to each network, how to maintain and maintain routing info
3. Describe how MAC addresses are used during the routing process
a MAC will never pass a router interface. MACs will change between router interfaces
4. View and interpret the routing table of a router
use show ip route to see the table
a "C" indicates directly connected, an "R" indicates RIP provided the route info, "S" means static
5. differentiate the three types of routing
static- manually configured
dynamic- routers automatically share info via protocol
default- a special route is configured for all traffic without a more specific destination network found in the table
6. Compare and contrast static and dynamic routing
static routing creates no routing update traffic which means less overhead on the routers and links- but it must be
configured manually and can't react if links are lost.
dynamic routing creates update traffic, but it can react to outages and choose the best route when multiple routes exist to the same network
7. Configure static routes at the CLI
route [dest network] [mask] [next hop address OR exit interface] [admin distance] [permanent]
Ex:
Corp(config)#
ip route 192.168.10.0 255.255.255.0 10.1.2.2 150
8. Create a default route
ip route 0.0.0.0 0.0.0.0 [ip address OR exit interface]
Ex:
R3(config)#
ip route 0.0.0.0 0.0.0.0 10.1.5.1 (ingress at Corp router- use if R3 cant identify route)
9. Understand administrative distance and its role in the selection of the best route
an integer from 0 (most trusted) to 255 (no traffic will pass via this route).
All routing protocols are assigned an AD but it can be changed at the CLI
10. Differentiate distance-vector, link-state, and hybrid routing protocols
distance vector- based on hop count (RIP)
link-state- multiple factors such as bandwidth and delay
hybrid- uses both
11. List mechanisms used to prevent routing loops in the network
max hop count, split horizon, route poisoning, holddown counters
12. Describe the counts used the operation of RIP
route update timer- (30) interval between routing updates
route invalid timer- (180, update x 3) before a route is determined invalid
holddown timer-(180) time info is supressed when a link is lost
route flush timer- (240) seconds before invalid and removal
13. Configure RIP routing
router rip
network x.x.x.x
the network(s) you want to advertise from your router. It only works if the other router has RIP enabled.
By enabling RIP, you are able to RECEIVE RIP data from other RIP routers.
by specifying a network, you are SENDING RIP data on that network
14. Identify commands used to verify RIP routing
show ip route will provide contents of the routing table with codes (R, C, S)
debug ip rip will show RIP updates being sent and received
15. Describe the differences between RIPv1 and RIPv2
RIPv1 sends a broadcast (255.255.255.255) every 30 seconds and has an AD of 120.
RIPv1 is classful only, does not send any mask info. No authentication between routers.
RIPv2 sends multicasts (224.0.0.9) every 30 seconds and sends mask info, which allows it to support classless networking, RIPv2 also supports
autentication between routers.
Chapter 8 Written Lab 8.0
1. At the appropriate prompt, create a static route to network 172.16.10.0/24 with a next-hop
gateway of 172.16.20.1 and an administrative distance of 150.
Router(config)#
ip route 172.16.10.0 255.255.255.0 172.16.20.1 150
2. When a PC sends a packet to another PC in a remote network, what destination IP address and MAC address will
be in the frame that it sends to it's default gateway?
the gateway interface MAC and the remote PC's IP
3. At the appropriate prompt, create a default route to 172.16.40.1
Router(config)#
ip route 0.0.0.0 0.0.0.0 172.16.40.1
"to" is the wrong word.. we are going TO any route VIA 172.16.40.1
4. If you are using default routing in a classless environment, what command must also be used?
Router(config)#
ip classless
5. On which type of network is a default route most beneficial?
stub
6. At the appropriate prompt, display the routing table on your router
Router#
show ip route
7. When creating a static or default route, you dont have to use the next-hop ip address;
you can instead use the ____________
exit interface
8. True/False: To reach a destination host, you must know the MAC address of the remote host
false, you need the MAC of your router
9. True/False: To reach a destination host, you must know the IP address of the remote host
true
10. At the appropriate prompt, execute the command required on a DCE serial interface that is not required
on a DTE serial interface
Router(config-if)#
clock rate X
11. At the appropriate prompt, enable RIP routing on the interface with the IP address 10.0.0.1/24
Router(config)#
router rip
Router(config-router)#
network 10.0.0.0
RIPv1 is CLASSFUL only... use the classful mask based on the first octet given
12. At the appropriate prompt, prevent a router from propagating IP information out serial 1
Router(config)#
router rip
Router(config-router)#
passive-interface S0/1
can receive RIP data but will not send
13. What routing loop prevention mechanism sends out a maximum hop count as soon as a link fails?
route poisoning
14. What routing loop prevention mechanism suppresses the resending of routing information to an interface
through which it was received?
split horizon
15. At the appropriate prompt display RIP routing updates as they are sent and received on the router
to the console session
Router#
debug ip rip
to turn it off:
Router#
undebug all
Chapter 8 Hands-on Labs
For these labs we will need a network with three routers.
Lab 8.1 Creating Static routes
first set the interfaces, then program the static routes
LabA(config)#
int s0/0/0
LabA(config-if)#
ip addr 172.16.20.1
LabA(config-if)#
int f0/0
LabA(config-if)#
ip addr 172.16.10.1
-----------------------------------------------------------------
LabA(config)#
ip route 172.16.30.0 255.255.255.0 172.16.20.2
LabA(config)#
ip route 172.16.40.0 255.255.255.0 172.16.20.2
LabB(config)#
int s0/0/0
LabB(config-if)#
ip addr 172.16.20.2
LabB(config-if)#
int s0/0/1
LabB(config-if)#
ip addr 172.16.30.1
-----------------------------------------------------------------
LabB(config)#
ip route 172.16.10.0 255.255.255.0 172.16.20.1
LabB(config)#
ip route 172.16.40.0 255.255.255.0 172.16.30.2
LabC(config)#
int s0/0/0
LabC(config-if)#
ip addr 172.16.30.2
LabC(config-if)#
int f0/0
LabC(config-if)#
ip addr 172.16.40.1
-----------------------------------------------------------------
LabC(config)#
ip route 172.16.10.0 255.255.255.0 172.16.30.1
LabC(config)#
ip route 172.16.20.0 255.255.255.0 172.16.30.1
Lab 8.2 RIP Configuration
remove the static routes, enable and configure RIP with the classful network id that covers the routes you want to advertise
LabA(config)#
no ip route 172.16.30.0 255.255.255.0 172.16.20.2
LabA(config)#
no ip route 172.16.40.0 255.255.255.0 172.16.20.2
LabA(config)#
router rip
LabA(config-router)#
network 172.16.0.0
LabA(config-router)#
do show ip route
Gateway of last resort is not set
172.16.0.0/16 is variably subnetted, 5 subnets, 2 masks
C 172.16.10.0/24 is directly connected, FastEthernet0/0
L 172.16.10.1/32 is directly connected, FastEthernet0/0
C 172.16.20.0/24 is directly connected, Serial0/0/0
L 172.16.20.1/32 is directly connected, Serial0/0/0
R 172.16.30.0/24 [120/1] via 172.16.20.2, 00:00:07, Serial0/0/0
from Lab B
LabB(config)#
no ip route 172.16.10.0 255.255.255.0 172.16.20.1
LabB(config)#
no ip route 172.16.40.0 255.255.255.0 172.16.30.2
LabB(config)#
router rip
LabB(config-router)#
network 172.16.0.0
LabB(config-router)#
do show ip route
Gateway of last resort is not set
172.16.0.0/16 is variably subnetted, 5 subnets, 2 masks
R 172.16.10.0/24 [120/1] via 172.16.20.1, 00:00:13, Serial0/0/0
from LabA
C 172.16.20.0/24 is directly connected, Serial0/0/0
L 172.16.20.2/32 is directly connected, Serial0/0/0
C 172.16.30.0/24 is directly connected, Serial0/0/1
L 172.16.30.1/32 is directly connected, Serial0/0/1
LabC(config)#
no ip route 172.16.10.0 255.255.255.0 172.16.30.1
LabC(config)#
no ip route 172.16.20.0 255.255.255.0 172.16.30.1
LabC(config)#
router rip
LabC(config-router)#
network 172.16.0.0
LabC(config-router)#
do show ip route
Gateway of last resort is not set
172.16.0.0/16 is variably subnetted, 3 subnets, 2 masks
R 172.16.20.0/24 [120/1] via 172.16.30.1, 00:00:05, Serial0/0/0
from LabB
C 172.16.30.0/24 is directly connected, Serial0/0/0
L 172.16.30.2/32 is directly connected, Serial0/0/0
Chapter 8 Review Questions
1. The Acme company uses a router named Gateway to connect to its ISP. The address of the ISP router is 206.143.5.2.
Which three commands could be configured on the gateway router to allow internet access to the entire network?
Set a default route:
Gateway(config)#
ip route 0.0.0.0 0.0.0.0 206.143.5.2 next hop IP
Gateway(config)#
ip route 0.0.0.0 0.0.0.0 S/0 exit interface instead of next hop IP
Gateway(config)#
ip default-network 206.143.5.0 next hop IP
2. What command will prevent RIP routing updates from exiting an interface but will sill allow the interface to receive RIP updates?
Router(config-if)#
passive-interface
3. Which two statemnts are true about ip route 172.16.4.0 255.255.255.0 192.168.4.2?
the command establishes a static route
the default admin distance is used (since we didnt give an AD argument)
4. What two destination addresses will be used by HostA to send data to the HTTPS server as shown in the following network?
MAC of RouterA f0/0 interface
IP address of the server
5. Which two statements are true about this output?
RIP: received v1 update from 192.168.40.2 on S0/1
192.168.50.0 in 16 hops (inaccessible)
RIP: sending v1 update to 255.255.255.255 via F0/0 (192.168.30.1)
RIP: build update entries
network 192.168.20.0 metric 1
network 192.168.40.0 metric 1
network 192.168.50.0 metric 16
RIP: sending v1 update to 255.255.255.255 via S0/1 (192.168.40.1)
true:
there are at least two routers exchanging information
192.168.40.2 will be successful
FALSE
there are three interfaces on the router participating in this update
false because we only see two interfaces represented in the output: S0/1(twice) and F0/0
a ping to 192.168.50.1 will be successful
false because that route has a metric of 16; it's unreachable
6. Describe split horizon
will not advertise a route back the the same router it was learned from
7. Which would be true if HostA is trying to communicate to HostB and interface F0/0 of RouterC goes down, as shown in the graphic?
RouterC will send an ICMP 'destination unreachable type' message to inform HostA that HostB is unreachable
8. Which two statements are true regarding classless routing protocols?
VLSM is permitted
RIPv2 supports classless
9. Which two are true regarding distance-vector vs link-state?
Distance vector sends the whole routing table out all active interfaces(even if a router isnt on the other end)at periodic time intervals
Link-state sends updates containing the state of its own links to all routers in the inter-network
10. Which command display RIP routing updates?
debug ip rip
11. What does RIPv2 use to prvent routing loops?
split horizon stops an update from being send on the same interface it was received
holdown timers allow time for a network to become stable in the case of a flapping link
12. A network administrator views the output from the show ip route command. A network that is advertised
by both RIP and EIGRP appears in the routing table flagged an EIGRP route. Why is the RIP route to this network not used in this routing table?
EIGRP has a lower AD.
RIP=120
OSPP=110
IGRP=110
EIGRP=90
13. You type debug ip rip on your router console and see that 172.16.10.0 is being advertised to you with a metric of 16. What does this mean?
it is inaccessible. in RIP if you see a route advertised with a metric of 16, it's inaccessible
14. What metric does RIPv2 use to find the best path to the remote network?
distance aka hop count
15. The Corporate router receives an IP packet with a source IP address of 192.168.214.20 and a destination address of 192.168.22.3. Looking at the output from the Corp router,
what will the router do with this packet?
Corp# show ip route
[cut]
R 192.168.215.0 [120/2] via 192.168.20.2, Serail0/0
R 192.168.115.0 [120/1] via 192.168.20.0, Serial0/0
R 192.168.30.0 [120/1] via 192.168.20.2, Serial0/0
C 192.168.20.0 is directly connected, Serial0/0
C 192.168.214.0 is directly connected, FastEthernet0/0
Since there is no route to that network, the router will discard the packet and send an ICMP destination unreachable message out F0/0 back the the source network
16. If your routing table has a static, a RIP and an EIGRP route to the same network, which route will be used by default?
Static routes have an admin distance of 1 by default. Unless you change it, a static route will always be used over any other
dynamically learned route.
17. You have the following routing table. Which network will NOT be placed in the neighbor routing table?
R 192.168.30.0/24 [120/1] via 192.168.40.1, Serial 0
C 192.168.40.0/24 is directly connected, Serial 0
172.16.0.0/2 is subnetted, 1 subnets
C 172.16.30.0 is directly connected, Loopback0
R 192.168.20.0/24 [120/1] via 192.168.40.1, Serial 0
R 10.0.0.0/8 [120/15] via 192.168.40.1, Serial 0
C 192.168.50.0/24 is directly connected, Ethernet 0
10.0.0.0 cant be placed in neighboring routing table because it is at 15 hops. 16 hops is invalid in RIP
18. Two connected routers are configured only with RIP. What will be the result when a router receives a routing update that contains a
higher-cost path to a network already in it's routing table?
The router will ignore the update because it is higher cost. When a routing update is received, the router first checks the AD and always chooses
the route with the lowest AD.
19.Which is true about route poisoning?
The router sets the metric for a downed link to "infinity".
20. Which is true about RIPv2?
it has all the same timers as RIPv1
------------------------------------------------------------------------------
END CHAPTER 8
54 hours 1-28 thru 2-14-22
original total 143 hours
11.5 hours review 12-23,24,26-22
review total hours 32
book page 428/822
avg 20 min/page (reading and exercises/labs)
Chapter 9 EIGRP and OSPF
pages 427-502, start 2-14-22-M
What is EIGRP?
Note it's not officially on CCNA 200-301 but it is still important to learn
Enhanced IGRP is a classless, enchanced distance vector protocol that uses the concept of an autonomous system to describe
the set of contigous routers that run the same routing protocol and share routing information.
Features:
Support for IP and IPv6 via protocol-dependent modules (seperate routing tables)
Considered classless
Support for summaries and discontiguous networks
Eficient neighbor discovery
communication via RTP- Reliable Transport Protocol
best path selection via Diffusing Updae Algorithm DUAL
Cisco considers EIGRP a "distance-vector" routing protocol
or an "advanced distance-vector" protocol
or a "hybrid" protocol
Configuring EIGRP on our network
------------------------------------------------------------------------------------------------------------------------------------
Corp(config)#
router eigrp ?
<1-65535> Autonomous system number
Corp(config)#
router eigrp 10
R2(config-router)#
network 10.0.0.0
after eigrp on R1- links from Corp to R1 are up
%DUAL-5-NBRCHANGE: IP-EIGRP 10: Neighbor 10.1.3.2 (Serial0/0/1) is up: new adjacency
%DUAL-5-NBRCHANGE: IP-EIGRP 10: Neighbor 10.1.2.2 (Serial0/0/0) is up: new adjacency
after eigrp on R2- link from Corp to R2 is up
%DUAL-5-NBRCHANGE: IP-EIGRP 10: Neighbor 10.1.4.2 (Serial0/1/0) is up: new adjacency
after eigrp on R3- link from Corp to R3 is up
%DUAL-5-NBRCHANGE: IP-EIGRP 10: Neighbor 10.1.5.2 (FastEthernet0/0) is up: new adjacency
------------------------------------------------------------------------------------------------------------------------------------
R1(config)#
router eigrp 10
R1(config-router)#
network 10.0.0.0
after eigrp on R1- link from R1 to Corp is up
%DUAL-5-NBRCHANGE: IP-EIGRP 10: Neighbor 10.1.3.1 (Serial0/0/1) is up: new adjacency
%DUAL-5-NBRCHANGE: IP-EIGRP 10: Neighbor 10.1.2.1 (Serial0/0/0) is up: new adjacency
R1(config-router)#
network 192.168.10.0
R1(config-router)#
network 192.168.20.0
------------------------------------------------------------------------------------------------------------------------------------
R2(config)#
router eigrp 10
R2(config-router)#
network 10.0.0.0
after eigrp on R2- link from R2 to Corp is up
%DUAL-5-NBRCHANGE: IP-EIGRP 10: Neighbor 10.1.4.1 (Serial0/0/0) is up: new adjacency
R1(config-router)#
network 192.168.30.0
R1(config-router)#
network 192.168.40.0
------------------------------------------------------------------------------------------------------------------------------------
R3(config)#
router eigrp 10
R3(config-router)#
network 10.0.0.0
after eigrp on R3- link from R3 to Corp is up
%DUAL-5-NBRCHANGE: IP-EIGRP 10: Neighbor 10.1.5.1 (FastEthernet0/0) is up: new adjacency
R1(config-router)#
network 172.16.0.0
------------------------------------------------------------------------------------------------------------------------------------
Corp#
show ip route
Gateway of last resort is not set
Gateway of last resort is not set
10.0.0.0/8 is variably subnetted, 10 subnets, 2 masks
C 10.1.1.0/24 is directly connected, Vlan1
L 10.1.1.1/32 is directly connected, Vlan1
C 10.1.2.0/24 is directly connected, Serial0/0/0
L 10.1.2.1/32 is directly connected, Serial0/0/0
C 10.1.3.0/24 is directly connected, Serial0/0/1
L 10.1.3.1/32 is directly connected, Serial0/0/1
C 10.1.4.0/24 is directly connected, Serial0/1/0
L 10.1.4.1/32 is directly connected, Serial0/1/0
C 10.1.5.0/24 is directly connected, FastEthernet0/0
L 10.1.5.1/32 is directly connected, FastEthernet0/0
172.16.0.0/16 is variably subnetted, 2 subnets, 2 masks
R 172.16.0.0/16 [120/1] via 10.1.5.2, 00:00:17, FastEthernet0/0
D 172.16.10.0/24 [90/28160] via 10.1.5.2, 00:00:16, FastEthernet0/0
via R3
D 192.168.10.0/24 [90/2172416] via 10.1.2.2, 00:19:13, Serial0/0/0
[90/2172416] via 10.1.3.2, 00:19:13, Serial0/0/1
D 192.168.20.0/24 [90/2172416] via 10.1.3.2, 00:19:05, Serial0/0/1
[90/2172416] via 10.1.2.2, 00:19:05, Serial0/0/0
via R1
D 192.168.30.0/24 [90/2172416] via 10.1.4.2, 00:01:31, Serial0/1/0
D 192.168.40.0/24 [90/2172416] via 10.1.4.2, 00:01:08, Serial0/1/0
via R2
The "D" routes are for DUAL- Diffusing Update Algorithm, indicating they are EIGRP routes.
Note that we have RIP and EIGRP set currently
------------------------------------------------------------------------------------------------------------------------------------
R1#
show ip route
Gateway of last resort is not set
10.0.0.0/8 is variably subnetted, 6 subnets, 2 masks
D 10.0.0.0/8 is a summary, 00:25:28, Null0
D 10.1.1.0/24 [90/27769856] via 10.1.2.1, 00:31:33, Serial0/0/0
[90/27769856] via 10.1.3.1, 00:31:30, Serial0/0/1
via Corp
C 10.1.2.0/24 is directly connected, Serial0/0/0
C 10.1.3.0/24 is directly connected, Serial0/0/1
D 10.1.4.0/24 [90/2681856] via 10.1.2.1, 00:31:33, Serial0/0/0
[90/2681856] via 10.1.3.1, 00:31:30, Serial0/0/1
D 10.1.5.0/24 [90/2172416] via 10.1.2.1, 00:31:33, Serial0/0/0
[90/2172416] via 10.1.3.1, 00:31:30, Serial0/0/1
via Corp
172.16.0.0/16 is variably subnetted, 2 subnets, 2 masks
R 172.16.0.0/16 [120/2] via 10.1.2.1, 00:00:07, Serial0/0/0
[120/2] via 10.1.3.1, 00:00:07, Serial0/0/1
D 172.16.10.0/24 [90/2172416] via 10.1.2.1, 00:06:31, Serial0/0/0
[90/2172416] via 10.1.3.1, 00:06:31, Serial0/0/1
via Corp
C 192.168.10.0/24 is directly connected, FastEthernet0/0
C 192.168.20.0/24 is directly connected, FastEthernet0/1
D 192.168.30.0/24 [90/2684416] via 10.1.3.1, 00:07:46, Serial0/0/1
[90/2684416] via 10.1.2.1, 00:07:46, Serial0/0/0
D 192.168.40.0/24 [90/2684416] via 10.1.2.1, 00:07:23, Serial0/0/0
[90/2684416] via 10.1.3.1, 00:07:23, Serial0/0/1
via Corp
------------------------------------------------------------------------------------------------------------------------------------
R2#
show ip route
Gateway of last resort is not set
10.0.0.0/8 is variably subnetted, 6 subnets, 2 masks
D 10.0.0.0/8 is a summary, 00:13:09, Null0
D 10.1.1.0/24 [90/27769856] via 10.1.4.1, 00:36:53, Serial0/0/0
D 10.1.2.0/24 [90/2681856] via 10.1.4.1, 00:36:53, Serial0/0/0
D 10.1.3.0/24 [90/2681856] via 10.1.4.1, 00:36:53, Serial0/0/0
via Corp
C 10.1.4.0/24 is directly connected, Serial0/0/0
D 10.1.5.0/24 [90/2172416] via 10.1.4.1, 00:36:53, Serial0/0/0
via Corp
172.16.0.0/16 is variably subnetted, 2 subnets, 2 masks
R 172.16.0.0/16 [120/2] via 10.1.4.1, 00:00:23, Serial0/0/0
D 172.16.10.0/24 [90/2172416] via 10.1.4.1, 00:11:54, Serial0/0/0
via Corp
D 192.168.10.0/24 [90/2684416] via 10.1.4.1, 00:30:51, Serial0/0/0
D 192.168.20.0/24 [90/2684416] via 10.1.4.1, 00:30:43, Serial0/0/0
via Corp
C 192.168.30.0/24 is directly connected, FastEthernet0/0
C 192.168.40.0/24 is directly connected, FastEthernet0/1
------------------------------------------------------------------------------------------------------------------------------------
R3#
show ip route
Gateway of last resort is 10.1.5.1 to network 0.0.0.0
10.0.0.0/8 is variably subnetted, 6 subnets, 2 masks
D 10.1.1.0/24 [90/25628160] via 10.1.5.1, 00:37:20, FastEthernet0/0
D 10.1.2.0/24 [90/2172416] via 10.1.5.1, 00:37:15, FastEthernet0/0
D 10.1.3.0/24 [90/2172416] via 10.1.5.1, 00:37:20, FastEthernet0/0
D 10.1.4.0/24 [90/2172416] via 10.1.5.1, 00:37:20, FastEthernet0/0
via Corp
C 10.1.5.0/24 is directly connected, FastEthernet0/0
L 10.1.5.2/32 is directly connected, FastEthernet0/0
172.16.0.0/16 is variably subnetted, 2 subnets, 2 masks
C 172.16.10.0/24 is directly connected, Dot11Radio0/0/0
L 172.16.10.1/32 is directly connected, Dot11Radio0/0/0
D 192.168.10.0/24 [90/2174976] via 10.1.5.1, 00:31:10, FastEthernet0/0
D 192.168.20.0/24 [90/2174976] via 10.1.5.1, 00:31:02, FastEthernet0/0
via Corp and R1
D 192.168.30.0/24 [90/2174976] via 10.1.5.1, 00:13:28, FastEthernet0/0
D 192.168.40.0/24 [90/2174976] via 10.1.5.1, 00:13:05, FastEthernet0/0
via Corp and R2
S* 0.0.0.0/0 [1/0] via 10.1.5.1
------------------------------------------------------------------------------------------------------------------------------------
turn off auto summary on each router
------------------------------------------------------------------------------------------------------------------------------------
Corp(config)#
router eigrp 10
Corp(config-router)#
no auto-summary
------------------------------------------------------------------------------------------------------------------------------------
R1(config)#
router eigrp 10
R1(config-router)#
no auto-summary
------------------------------------------------------------------------------------------------------------------------------------
R2(config)#
router eigrp 10
R2(config-router)#
no auto-summary
------------------------------------------------------------------------------------------------------------------------------------
R3(config)#
router eigrp 10
R3(config-router)#
no auto-summary
------------------------------------------------------------------------------------------------------------------------------------
compare Corp before and after auto summary turned off
------------------------------------------------------------------------------------------------------------------------------------
auto summary on
Corp#
show ip route
Gateway of last resort is not set
10.0.0.0/8 is variably subnetted, 10 subnets, 2 masks
C 10.1.1.0/24 is directly connected, Vlan1
L 10.1.1.1/32 is directly connected, Vlan1
C 10.1.2.0/24 is directly connected, Serial0/0/0
L 10.1.2.1/32 is directly connected, Serial0/0/0
C 10.1.3.0/24 is directly connected, Serial0/0/1
L 10.1.3.1/32 is directly connected, Serial0/0/1
C 10.1.4.0/24 is directly connected, Serial0/1/0
L 10.1.4.1/32 is directly connected, Serial0/1/0
C 10.1.5.0/24 is directly connected, FastEthernet0/0
L 10.1.5.1/32 is directly connected, FastEthernet0/0
172.16.0.0/16 is variably subnetted, 2 subnets, 2 masks
R 172.16.0.0/16 [120/1] via 10.1.5.2, 00:00:17, FastEthernet0/0
D 172.16.10.0/24 [90/28160] via 10.1.5.2, 00:00:16, FastEthernet0/0
via R3
D 192.168.10.0/24 [90/2172416] via 10.1.2.2, 00:19:13, Serial0/0/0
[90/2172416] via 10.1.3.2, 00:19:13, Serial0/0/1
D 192.168.20.0/24 [90/2172416] via 10.1.3.2, 00:19:05, Serial0/0/1
[90/2172416] via 10.1.2.2, 00:19:05, Serial0/0/0
via R1
D 192.168.30.0/24 [90/2172416] via 10.1.4.2, 00:01:31, Serial0/1/0
D 192.168.40.0/24 [90/2172416] via 10.1.4.2, 00:01:08, Serial0/1/0
via R2
auto summary off
Corp#
show ip route
Gateway of last resort is not set
10.0.0.0/8 is variably subnetted, 10 subnets, 2 masks
C 10.1.1.0/24 is directly connected, Vlan1
L 10.1.1.1/32 is directly connected, Vlan1
C 10.1.2.0/24 is directly connected, Serial0/0/0
L 10.1.2.1/32 is directly connected, Serial0/0/0
C 10.1.3.0/24 is directly connected, Serial0/0/1
L 10.1.3.1/32 is directly connected, Serial0/0/1
C 10.1.4.0/24 is directly connected, Serial0/1/0
L 10.1.4.1/32 is directly connected, Serial0/1/0
C 10.1.5.0/24 is directly connected, FastEthernet0/0
L 10.1.5.1/32 is directly connected, FastEthernet0/0
172.16.0.0/16 is variably subnetted, 2 subnets, 2 masks
R 172.16.0.0/16 [120/1] via 10.1.5.2, 00:00:12, FastEthernet0/0
D 172.16.10.0/24 [90/28160] via 10.1.5.2, 00:45:29, FastEthernet0/0
via R3
D 192.168.10.0/24 [90/2172416] via 10.1.2.2, 00:01:08, Serial0/0/0
[90/2172416] via 10.1.3.2, 00:01:08, Serial0/0/1
D 192.168.20.0/24 [90/2172416] via 10.1.2.2, 00:01:08, Serial0/0/0
[90/2172416] via 10.1.3.2, 00:01:08, Serial0/0/1
via R1
D 192.168.30.0/24 [90/2172416] via 10.1.4.2, 00:00:46, Serial0/1/0
D 192.168.40.0/24 [90/2172416] via 10.1.4.2, 00:00:46, Serial0/1/0
via R2
We are still seeing an auto summarized route- 172.16.0.0 coming from R3.
The book discusses enabling EIGRP auto summary on all four routers- nothing is said about disabling it within RIP or turning off RIP.
RIP auto summarizes by default. We cant get rid of this auto summary route while RIP is on.
Moving on...
VERIFYING EIGRP
several commands available to verify and troubleshoot
show ip route
show the entire routing table
show ip route eigrp
show only EIGRP entries in the routing table
show ip eigrp neighbors
show all EIGRP neigbors
show ip eigrp topology
show entries in the EIGRP topology table
show ip protocols
shows routing protocols configuration
debug eigrp packet
shows hello packets sent/received between adjacent routers
debug ip eigrp events
shows EIGRP changes and updates as they occur on your network
lets take a look at the state of our 4 routers. RIP and EIGRP are running on each.
Notice how this command is giving different outputs between the two different IOS versions
IOS 15.1
Corp#
show ip protocols
Routing Protocol is "eigrp 10 "
Outgoing update filter list for all interfaces is not set
Incoming update filter list for all interfaces is not set
Default networks flagged in outgoing updates
Default networks accepted from incoming updates
Redistributing: eigrp 10
EIGRP-IPv4 Protocol for AS(10)
Metric weight K1=1, K2=0, K3=1, K4=0, K5=0
NSF-aware route hold timer is 240
Router-ID: 10.1.1.1
Topology : 0 (base)
Active Timer: 3 min
Distance: internal 90 external 170
Maximum path: 4
Maximum hopcount 100
Maximum metric variance 1
Automatic Summarization: disabled
Automatic address summarization:
Maximum path: 4
Routing for Networks:
10.0.0.0
Routing Information Sources:
Gateway Distance Last Update
10.1.5.2 90 0
10.1.3.2 90 6464
10.1.2.2 90 6795
10.1.4.2 90 7955
Distance: internal 90 external 170
Routing Protocol is "rip"
Sending updates every 30 seconds, next due in 10 seconds
Invalid after 180 seconds, hold down 180, flushed after 240
Outgoing update filter list for all interfaces is not set
Incoming update filter list for all interfaces is not set
Redistributing: rip
Default version control: send version 2, receive 2
Interface Send Recv Triggered RIP Key-chain
Vlan1 2 2
FastEthernet0/0 2 2
Serial0/1/0 2 2
Serial0/0/1 2 2
Serial0/0/0 2 2
Automatic network summarization is in effect
Maximum path: 4
Routing for Networks:
10.0.0.0
Passive Interface(s):
Routing Information Sources:
Gateway Distance Last Update
10.1.5.2 120 00:00:12
10.1.3.2 120 00:00:16
10.1.2.2 120 00:00:16
10.1.4.2 120 00:00:13
Distance: (default is 120)
IOS 12.4
R1#
show ip protocols
Routing Protocol is "eigrp 10 "
Outgoing update filter list for all interfaces is not set
Incoming update filter list for all interfaces is not set
Default networks flagged in outgoing updates
Default networks accepted from incoming updates
EIGRP metric weight K1=1, K2=0, K3=1, K4=0, K5=0
EIGRP maximum hopcount 100
EIGRP maximum metric variance 1
Redistributing: eigrp 10
Automatic network summarization is not in effect
Maximum path: 4
Routing for Networks:
10.0.0.0
192.168.10.0
192.168.20.0
Routing Information Sources:
Gateway Distance Last Update
10.1.3.1 90 6465
10.1.2.1 90 6794
Distance: internal 90 external 170
Routing Protocol is "rip"
Sending updates every 30 seconds, next due in 21 seconds
Invalid after 180 seconds, hold down 180, flushed after 240
Outgoing update filter list for all interfaces is not set
Incoming update filter list for all interfaces is not set
Redistributing: rip
Default version control: send version 2, receive 2
Interface Send Recv Triggered RIP Key-chain
FastEthernet0/0 2 2
FastEthernet0/1 2 2
Serial0/0/0 2 2
Serial0/0/1 2 2
Automatic network summarization is not in effect
Maximum path: 4
Routing for Networks:
10.0.0.0
192.168.10.0
192.168.20.0
Passive Interface(s):
Routing Information Sources:
Gateway Distance Last Update
10.1.3.1 120 00:00:06
10.1.2.1 120 00:00:06
Distance: (default is 120)
IOS 12.4
R2#
show ip protocols
Routing Protocol is "eigrp 10 "
Outgoing update filter list for all interfaces is not set
Incoming update filter list for all interfaces is not set
Default networks flagged in outgoing updates
Default networks accepted from incoming updates
EIGRP metric weight K1=1, K2=0, K3=1, K4=0, K5=0
EIGRP maximum hopcount 100
EIGRP maximum metric variance 1
Redistributing: eigrp 10
Automatic network summarization is not in effect
Maximum path: 4
Routing for Networks:
10.0.0.0
192.168.30.0
192.168.40.0
Routing Information Sources:
Gateway Distance Last Update
10.1.4.1 90 7955
Distance: internal 90 external 170
Routing Protocol is "rip"
Sending updates every 30 seconds, next due in 11 seconds
Invalid after 180 seconds, hold down 180, flushed after 240
Outgoing update filter list for all interfaces is not set
Incoming update filter list for all interfaces is not set
Redistributing: rip
Default version control: send version 2, receive 2
Interface Send Recv Triggered RIP Key-chain
FastEthernet0/0 2 2
FastEthernet0/1 2 2
Serial0/0/0 2 2
Automatic network summarization is in effect
Maximum path: 4
Routing for Networks:
10.0.0.0
192.168.30.0
192.168.40.0
Passive Interface(s):
Routing Information Sources:
Gateway Distance Last Update
10.1.4.1 120 00:00:20
Distance: (default is 120)
IOS 15.1
R3#
show ip protocols
Routing Protocol is "eigrp 10 "
Outgoing update filter list for all interfaces is not set
Incoming update filter list for all interfaces is not set
Default networks flagged in outgoing updates
Default networks accepted from incoming updates
Redistributing: eigrp 10
EIGRP-IPv4 Protocol for AS(10)
Metric weight K1=1, K2=0, K3=1, K4=0, K5=0
NSF-aware route hold timer is 240
Router-ID: 10.1.5.2
Topology : 0 (base)
Active Timer: 3 min
Distance: internal 90 external 170
Maximum path: 4
Maximum hopcount 100
Maximum metric variance 1
Automatic Summarization: disabled
Automatic address summarization:
Maximum path: 4
Routing for Networks:
10.0.0.0
172.16.0.0
Routing Information Sources:
Gateway Distance Last Update
10.1.5.1 90 0
Distance: internal 90 external 170
Routing Protocol is "rip"
Sending updates every 30 seconds, next due in 27 seconds
Invalid after 180 seconds, hold down 180, flushed after 240
Outgoing update filter list for all interfaces is not set
Incoming update filter list for all interfaces is not set
Redistributing: rip
Default version control: send version 2, receive 2
Interface Send Recv Triggered RIP Key-chain
Dot11Radio0/0/0 2 2
FastEthernet0/0 2 2
Automatic network summarization is not in effect
Maximum path: 4
Routing for Networks:
10.0.0.0
172.16.0.0
Passive Interface(s):
Routing Information Sources:
Gateway Distance Last Update
10.1.5.1 120 00:00:02
Distance: (default is 120)
I'm also noticing that we have inconsistent auto-summarization settings- I was having trouble with this earlier. The book discusses
getting rid of the 172.16.0.0 summarized route in the EIGRP settings. I was not able to get rid of it, I think because RIP is still on, and RIP forces auto-summary
Part of the challenge here is that the book is strictly dealing with IOS 12.4
I will now make sure to turn auto summary off for both RIP and EIGRP on each of the four routers.
OK the part I am forgetting is that we are running RIP V2 which does not force auto-summary but runs it optionally, and we must turn it off to avoid auto summarization.
Corp(config)#
router rip
Corp(config-router)#
no auto-summary
Corp(config-router)#
router eigrp 10
Corp(config-router)#
no auto-summary
R1(config)#
router rip
R1(config-router)#
no auto-summary
R1(config-router)#
router eigrp 10
R1(config-router)#
no auto-summary
R1(config)#
router rip
R1(config-router)#
no auto-summary
R1(config-router)#
router eigrp 10
R2(config-router)#
no auto-summary
R3(config)#
router rip
R3(config-router)#
no auto-summary
R3(config-router)#
router eigrp 10
R3(config-router)#
no auto-summary
and lets see how the output looks now. This time I'll do show ip protocols and
show ip route side by side for each router
IOS 15.1
Corp#
show ip protocols
Routing Protocol is "eigrp 10 "
Outgoing update filter list for all interfaces is not set
Incoming update filter list for all interfaces is not set
Default networks flagged in outgoing updates
Default networks accepted from incoming updates
Redistributing: eigrp 10
EIGRP-IPv4 Protocol for AS(10)
Metric weight K1=1, K2=0, K3=1, K4=0, K5=0
NSF-aware route hold timer is 240
Router-ID: 10.1.1.1
Topology : 0 (base)
Active Timer: 3 min
Distance: internal 90 external 170
Maximum path: 4
Maximum hopcount 100
Maximum metric variance 1
Automatic Summarization: disabled
Automatic address summarization:
Maximum path: 4
Routing for Networks:
10.0.0.0
Routing Information Sources:
Gateway Distance Last Update
10.1.5.2 90 0
10.1.3.2 90 6464
10.1.2.2 90 6795
10.1.4.2 90 7955
Distance: internal 90 external 170
Routing Protocol is "rip" doesnt necessarily mean RIPv1
Sending updates every 30 seconds, next due in 3 seconds
Invalid after 180 seconds, hold down 180, flushed after 240
Outgoing update filter list for all interfaces is not set
Incoming update filter list for all interfaces is not set
Redistributing: rip
Default version control: send version 2, receive 2 RIPv2 is specified
Interface Send Recv Triggered RIP Key-chain
Vlan1 2 2
FastEthernet0/0 2 2
Serial0/1/0 2 2
Serial0/0/1 2 2
Serial0/0/0 2 2
Automatic network summarization is not in effect
Maximum path: 4
Routing for Networks:
10.0.0.0
Passive Interface(s):
Routing Information Sources:
Gateway Distance Last Update
10.1.5.2 120 00:00:02
10.1.3.2 120 00:00:21
10.1.2.2 120 00:00:21
10.1.4.2 120 00:00:04
Distance: (default is 120)
IOS 15.1
Corp#
show ip route
Gateway of last resort is not set
10.0.0.0/8 is variably subnetted, 10 subnets, 2 masks
C 10.1.1.0/24 is directly connected, Vlan1
L 10.1.1.1/32 is directly connected, Vlan1
C 10.1.2.0/24 is directly connected, Serial0/0/0
L 10.1.2.1/32 is directly connected, Serial0/0/0
C 10.1.3.0/24 is directly connected, Serial0/0/1
L 10.1.3.1/32 is directly connected, Serial0/0/1
C 10.1.4.0/24 is directly connected, Serial0/1/0
L 10.1.4.1/32 is directly connected, Serial0/1/0
C 10.1.5.0/24 is directly connected, FastEthernet0/0
L 10.1.5.1/32 is directly connected, FastEthernet0/0
172.16.0.0/24 is subnetted, 1 subnets
D 172.16.10.0/24 [90/28160] via 10.1.5.2, 00:57:25, FastEthernet0/0
D 192.168.10.0/24 [90/2172416] via 10.1.3.2, 00:57:20, Serial0/0/1
[90/2172416] via 10.1.2.2, 00:57:20, Serial0/0/0
D 192.168.20.0/24 [90/2172416] via 10.1.3.2, 00:57:20, Serial0/0/1
[90/2172416] via 10.1.2.2, 00:57:20, Serial0/0/0
D 192.168.30.0/24 [90/2172416] via 10.1.4.2, 00:57:19, Serial0/1/0
D 192.168.40.0/24 [90/2172416] via 10.1.4.2, 00:57:19, Serial0/1/0
IOS 12.4
R1#
show ip protocols
Routing Protocol is "eigrp 10 "
Outgoing update filter list for all interfaces is not set
Incoming update filter list for all interfaces is not set
Default networks flagged in outgoing updates
Default networks accepted from incoming updates
EIGRP metric weight K1=1, K2=0, K3=1, K4=0, K5=0
EIGRP maximum hopcount 100
EIGRP maximum metric variance 1
Redistributing: eigrp 10
Automatic network summarization is not in effect
Maximum path: 4
Routing for Networks:
10.0.0.0
192.168.10.0
192.168.20.0
Routing Information Sources:
Gateway Distance Last Update
10.1.3.1 90 6465
10.1.2.1 90 6794
Distance: internal 90 external 170
Routing Protocol is "rip"
Sending updates every 30 seconds, next due in 26 seconds
Invalid after 180 seconds, hold down 180, flushed after 240
Outgoing update filter list for all interfaces is not set
Incoming update filter list for all interfaces is not set
Redistributing: rip
Default version control: send version 2, receive 2
Interface Send Recv Triggered RIP Key-chain
FastEthernet0/0 2 2
FastEthernet0/1 2 2
Serial0/0/0 2 2
Serial0/0/1 2 2
Automatic network summarization is not in effect
Maximum path: 4
Routing for Networks:
10.0.0.0
192.168.10.0
192.168.20.0
Passive Interface(s):
Routing Information Sources:
Gateway Distance Last Update
10.1.3.1 120 00:00:03
10.1.2.1 120 00:00:03
Distance: (default is 120)
IOS 12.4
R1#
show ip route
Gateway of last resort is not set
10.0.0.0/24 is subnetted, 5 subnets
D 10.1.1.0 [90/27769856] via 10.1.3.1, 00:54:47, Serial0/0/1
[90/27769856] via 10.1.2.1, 00:54:47, Serial0/0/0
C 10.1.2.0 is directly connected, Serial0/0/0
C 10.1.3.0 is directly connected, Serial0/0/1
D 10.1.4.0 [90/2681856] via 10.1.3.1, 00:54:47, Serial0/0/1
[90/2681856] via 10.1.2.1, 00:54:47, Serial0/0/0
D 10.1.5.0 [90/2172416] via 10.1.3.1, 00:54:47, Serial0/0/1
[90/2172416] via 10.1.2.1, 00:54:47, Serial0/0/0
172.16.0.0/24 is subnetted, 1 subnets
D 172.16.10.0 [90/2172416] via 10.1.3.1, 00:54:47, Serial0/0/1
[90/2172416] via 10.1.2.1, 00:54:47, Serial0/0/0
C 192.168.10.0/24 is directly connected, FastEthernet0/0
C 192.168.20.0/24 is directly connected, FastEthernet0/1
D 192.168.30.0/24 [90/2684416] via 10.1.3.1, 00:54:46, Serial0/0/1
[90/2684416] via 10.1.2.1, 00:54:46, Serial0/0/0
D 192.168.40.0/24 [90/2684416] via 10.1.3.1, 00:54:46, Serial0/0/1
[90/2684416] via 10.1.2.1, 00:54:46, Serial0/0/0
note that the DUAL routes being advertised from the 10.0.0.0 networks are all specific to the third octet.. that's because we are reading those routes
from their source, aka the router which they are directly connected to, Corp.
and on Corp, those networks were added to the interfaces with a /24 mask.
so even though our EIGRP config doesnt specifically include /24 networks.. we told it to include anything with a 10.x.x.x
Corp is advertising to R1 our /24 network interfaces that have a 10 in the first octet, EXCEPT the two which are directly connected to R1
10.1.1.0
10.1.4.0
10.1.5.0
are assumed to be the subnets based on the info we configured, which was 10.1.4.1/24 on corp, and 10.1.4.2/24 on r2 s0/0/0
nowhere in this configuration, have we entered the 10.1.4.0 network.
EIGRP is figuring it out based on the /24 mask we gave when assiging he IPs to the interfaces
IOS 12.4
R2#
show ip protocols
Routing Protocol is "eigrp 10 "
Outgoing update filter list for all interfaces is not set
Incoming update filter list for all interfaces is not set
Default networks flagged in outgoing updates
Default networks accepted from incoming updates
EIGRP metric weight K1=1, K2=0, K3=1, K4=0, K5=0
EIGRP maximum hopcount 100
EIGRP maximum metric variance 1
Redistributing: eigrp 10
Automatic network summarization is not in effect
Maximum path: 4
Routing for Networks:
10.0.0.0
192.168.30.0
192.168.40.0
Routing Information Sources:
Gateway Distance Last Update
10.1.4.1 90 7955
Distance: internal 90 external 170
Routing Protocol is "rip"
Sending updates every 30 seconds, next due in 18 seconds
Invalid after 180 seconds, hold down 180, flushed after 240
Outgoing update filter list for all interfaces is not set
Incoming update filter list for all interfaces is not set
Redistributing: rip
Default version control: send version 2, receive 2
Interface Send Recv Triggered RIP Key-chain
FastEthernet0/0 2 2
FastEthernet0/1 2 2
Serial0/0/0 2 2
Automatic network summarization is not in effect
Maximum path: 4
Routing for Networks:
10.0.0.0
192.168.30.0
192.168.40.0
Passive Interface(s):
Routing Information Sources:
Gateway Distance Last Update
10.1.4.1 120 00:00:07
Distance: (default is 120)
IOS 12.4
R2#
show ip route
Gateway of last resort is not set
10.0.0.0/24 is subnetted, 5 subnets
D 10.1.1.0 [90/27769856] via 10.1.4.1, 00:59:10, Serial0/0/0
D 10.1.2.0 [90/2681856] via 10.1.4.1, 00:59:10, Serial0/0/0
D 10.1.3.0 [90/2681856] via 10.1.4.1, 00:59:10, Serial0/0/0
C 10.1.4.0 is directly connected, Serial0/0/0
D 10.1.5.0 [90/2172416] via 10.1.4.1, 00:59:10, Serial0/0/0
172.16.0.0/24 is subnetted, 1 subnets
D 172.16.10.0 [90/2172416] via 10.1.4.1, 00:59:10, Serial0/0/0
D 192.168.10.0/24 [90/2684416] via 10.1.4.1, 00:59:10, Serial0/0/0
D 192.168.20.0/24 [90/2684416] via 10.1.4.1, 00:59:10, Serial0/0/0
C 192.168.30.0/24 is directly connected, FastEthernet0/0
C 192.168.40.0/24 is directly connected, FastEthernet0/1
IOS 15.1
R3#
show ip protocols
Routing Protocol is "eigrp 10 "
Outgoing update filter list for all interfaces is not set
Incoming update filter list for all interfaces is not set
Default networks flagged in outgoing updates
Default networks accepted from incoming updates
Redistributing: eigrp 10
EIGRP-IPv4 Protocol for AS(10)
Metric weight K1=1, K2=0, K3=1, K4=0, K5=0
NSF-aware route hold timer is 240
Router-ID: 10.1.5.2
Topology : 0 (base)
Active Timer: 3 min
Distance: internal 90 external 170
Maximum path: 4
Maximum hopcount 100
Maximum metric variance 1
Automatic Summarization: disabled
Automatic address summarization:
Maximum path: 4
Routing for Networks:
10.0.0.0
172.16.0.0
Routing Information Sources:
Gateway Distance Last Update
10.1.5.1 90 0
Distance: internal 90 external 170
Routing Protocol is "rip"
Sending updates every 30 seconds, next due in 15 seconds
Invalid after 180 seconds, hold down 180, flushed after 240
Outgoing update filter list for all interfaces is not set
Incoming update filter list for all interfaces is not set
Redistributing: rip
Default version control: send version 2, receive 2
Interface Send Recv Triggered RIP Key-chain
Dot11Radio0/0/0 2 2
FastEthernet0/0 2 2
Automatic network summarization is not in effect
Maximum path: 4
Routing for Networks:
10.0.0.0
172.16.0.0
Passive Interface(s):
Routing Information Sources:
Gateway Distance Last Update
10.1.5.1 120 00:00:14
Distance: (default is 120)
IOS 15.1
R3#
show ip route
Gateway of last resort is 10.1.5.1 to network 0.0.0.0
10.0.0.0/8 is variably subnetted, 6 subnets, 2 masks
D 10.1.1.0/24 [90/25628160] via 10.1.5.1, 00:59:52, FastEthernet0/0
D 10.1.2.0/24 [90/2172416] via 10.1.5.1, 00:59:47, FastEthernet0/0
D 10.1.3.0/24 [90/2172416] via 10.1.5.1, 00:59:52, FastEthernet0/0
D 10.1.4.0/24 [90/2172416] via 10.1.5.1, 00:59:52, FastEthernet0/0
C 10.1.5.0/24 is directly connected, FastEthernet0/0
L 10.1.5.2/32 is directly connected, FastEthernet0/0
172.16.0.0/16 is variably subnetted, 2 subnets, 2 masks
C 172.16.10.0/24 is directly connected, Dot11Radio0/0/0
L 172.16.10.1/32 is directly connected, Dot11Radio0/0/0
D 192.168.10.0/24 [90/2174976] via 10.1.5.1, 00:59:47, FastEthernet0/0
D 192.168.20.0/24 [90/2174976] via 10.1.5.1, 00:59:47, FastEthernet0/0
D 192.168.30.0/24 [90/2174976] via 10.1.5.1, 00:59:46, FastEthernet0/0
D 192.168.40.0/24 [90/2174976] via 10.1.5.1, 00:59:46, FastEthernet0/0
S* 0.0.0.0/0 [1/0] via 10.1.5.1
Observations:
Since this is a 15.1 router, we always get a "L" local route when
we have a "C" connected route. In R3's case, the 172.16.10.0 network
is directly connected. The interface which connects it, 172.16.10.1,
counts as a "local" route. This is NOT the case on the 12.4 routers.
looking to the left, our protocol output tells us two key facts for both EIGRP and RIP:
Routing for networks:
10.0.0.0
172.16.0.0
R3 is responsible for *sending* data about these two networks to our other EIGRP routers...
"I'm R3 and I can connect you to networks on the R3
router or networks on the Corp router"
Notice how the 192 networks arent listed. R3 isnt connected to a 192 network directly, nor is it connected to a neighbor who is directly connected.
If I, as a client, am sending data to a 192 network from the 172 network, I will start
at R3. Since R3 is receiving routes for the 192 networks via Corp, I will be able to reach a 192 network via Corp.
My connection to corp will happen VIA a "10.0.0.0" route.
R3 is technically only routing for 172 and 10 networks. Beyond that, it could potentially connect to many other different networks. But in terms of the R3 routing table,
all it can offer is a path out to the 172 network or the 10 network
Routing information sources:
10.1.5.1
In this case I can see that R3 is receiving routing data from one interface only,
and that is it's link to Corp. Some of the data we are receiving from Corp actually originates
at other routers, but we cant see that here; the data comes to us from Corp, and that is all we know
EIGRP TERMINOLOGY
FEASIBLE DISTANCE (FD)
the best metric among all paths, including to the next hop neighbor. You will only see the route with the lowest FD appear in the routing table
The FD is calculated by adding the reported distance from the neighbor (AD) plus the metric to that neighbor
ADVERTISED DISTANCE (AD)
the metric of a remote network as reported by a neighbor, listed second in parenthesis in toplogy table
P 192.168.20.0/24, 2 successors, FD is 2172416
via 10.1.3.2 (2172416/28160), Serial0/0/1
feasible / advertised
Neighbor Table
each router keeps state information about adjacent neighbors.. When a new neighbor is learned, the address and interface are recorded.
The neighbor table is stored in RAM.
Sequence numbres are used to match acks with update packets. The last squence number received from a neighbor is recorded so out of order packets
can be detected
Topology Table
acted upon by DUAL Diffusing Update Alogorithm. Contains all destinations advertised by neighboring routers.
For each neighbor, the adversited distance, which comes only from that neighbor's routing table, is recorded
The feasible distance is also recorded.
Feasible Successor
a PATH whose advertised distance is less than the feasible distance of the current succesor, and is considered a backup route.
EIGRP keeps up to 16 feasible successors in the toplogy table.
The one with the best metric (The Successor) is copied and placed into the routing table
Successor
the best route to a remote network, used by EIGRP to forward traffic. It's backed up by a feasible successor, if one is available.
lets demo some more of the commands
VERIFYING EIGRP
several commands available to verify and troubleshoot
show ip route
show the entire routing table
show ip route eigrp
show only EIGRP entries in the routing table
show ip eigrp neighbors
show all EIGRP neigbors
show ip eigrp topology
show entries in the EIGRP topology table
show ip protocols
shows routing protocols configuration
debug eigrp packet
shows hello packets sent/received between adjacent routers
debug ip eigrp events
shows EIGRP changes and updates as they occur on your network
Corp#
show ip eigrp ?
interfaces IP-EIGRP interfaces
neighbors IP-EIGRP neighbors
topology IP-EIGRP Topology Table
traffic IP-EIGRP Traffic Statistics
Corp#
show ip eigrp topology
IP-EIGRP Topology Table for AS 10/ID(10.1.5.1)
Codes: P - Passive, A - Active, U - Update, Q - Query, R - Reply,
r - Reply status
P 10.1.1.0/24, 1 successors, FD is 25625600
via Connected, Vlan1
P 10.1.2.0/24, 1 successors, FD is 2169856
via Connected, Serial0/0/0
P 10.1.3.0/24, 1 successors, FD is 2169856
via Connected, Serial0/0/1
P 10.1.4.0/24, 1 successors, FD is 2169856
via Connected, Serial0/1/0
P 10.1.5.0/24, 1 successors, FD is 28160
via Connected, FastEthernet0/0
P 172.16.10.0/24, 1 successors, FD is 28160
via 10.1.5.2 (28160/25600), FastEthernet0/0
P 192.168.10.0/24, 2 successors, FD is 2172416
via 10.1.3.2 (2172416/28160), Serial0/0/1
via 10.1.2.2 (2172416/28160), Serial0/0/0
P 192.168.20.0/24, 2 successors, FD is 2172416
via 10.1.3.2 (2172416/28160), Serial0/0/1
via 10.1.2.2 (2172416/28160), Serial0/0/0
P 192.168.30.0/24, 1 successors, FD is 2172416
via 10.1.4.2 (2172416/28160), Serial0/1/0
P 192.168.40.0/24, 1 successors, FD is 2172416
via 10.1.4.2 (2172416/28160), Serial0/1/0
the "P" preceding each entry is for PASSIVE
these routes are in a passive state, which is good
if they move to an ACTIVE state, it means the have lost their path in the network and looking for a replacement.
Each entry also shows the FEASIBLE DISTANCE, the next hop address, and the local egress interface
Corp#
show ip eigrp neighbors
IP-EIGRP neighbors for process 10
H Address Interface Hold Uptime SRTT RTO Q Seq
(sec) (ms) Cnt Num
0 10.1.5.2 Fa0/0 14 02:00:05 40 1000 0 19
1 10.1.3.2 Se0/0/1 13 01:59:59 40 1000 0 14
2 10.1.2.2 Se0/0/0 13 01:59:59 40 1000 0 13
3 10.1.4.2 Se0/1/0 12 01:59:57 40 1000 0 15
fields:
H - the order in which the neighbors were discovered
hold - how long the router will wait for a hello packet
uptime - how long the neigborship has been established
SRTT - smooth round trip timer - the time it takes for a round trip from this router, to neighbor, and back.
SRTT is used to determine how long to wait for a MULTICAST reply.
if a reply isnt received in time, the router switches to UNICASTS
RTO - Retransmission Time Out- is the time EIGRP waits before retransmitting a packet from the retransmission queue
Q - indicates wheter there are oustanding messages in the queue
Seq - indicates the sequence number of the last update from that neighbor. This is used to maintain syncrhonization and avoid duplicate
or out-of-sequence processing of messages
Corp#
show ip route eigrp
172.16.0.0/24 is subnetted, 1 subnets
D 172.16.10.0 [90/28160] via 10.1.5.2, 02:08:04, FastEthernet0/0
D 192.168.10.0/24 [90/2172416] via 10.1.3.2, 02:07:59, Serial0/0/1
[90/2172416] via 10.1.2.2, 02:07:59, Serial0/0/0
D 192.168.20.0/24 [90/2172416] via 10.1.3.2, 02:07:59, Serial0/0/1
[90/2172416] via 10.1.2.2, 02:07:59, Serial0/0/0
D 192.168.30.0/24 [90/2172416] via 10.1.4.2, 02:07:58, Serial0/1/0
D 192.168.40.0/24 [90/2172416] via 10.1.4.2, 02:07:58, Serial0/1/0
Corp#
show ip eigrp interfaces
IP-EIGRP interfaces for process 10
Xmit Queue Mean Pacing Time Multicast Pending
Interface Peers Un/Reliable SRTT Un/Reliable Flow Timer Routes
Vlan 0 0/0 1236 0/10 0 0
Fa0/0 1 0/0 1236 0/10 0 0
Se0/1/0 1 0/0 1236 0/10 0 0
Se0/0/1 1 0/0 1236 0/10 0 0
Se0/0/0 1 0/0 1236 0/10 0 0
Corp#
show ip protocols
Routing Protocol is "eigrp 10 "
Outgoing update filter list for all interfaces is not set
Incoming update filter list for all interfaces is not set
Default networks flagged in outgoing updates
Default networks accepted from incoming updates
Redistributing: eigrp 10
EIGRP-IPv4 Protocol for AS(10)
Metric weight K1=1, K2=0, K3=1, K4=0, K5=0 using K1 bandwidth and K2 delay by default
NSF-aware route hold timer is 240
Router-ID: 10.1.1.1
Topology : 0 (base)
Active Timer: 3 min
Distance: internal 90 external 170
Maximum path: 4
Maximum hopcount 100
Maximum metric variance 1
Automatic Summarization: disabled
Automatic address summarization:
Maximum path: 4
Routing for Networks:
10.0.0.0
Routing Information Sources:
Gateway Distance Last Update
10.1.5.2 90 0
10.1.3.2 90 8936
10.1.4.2 90 9511
10.1.2.2 90 9597
Distance: internal 90 external 170
Routing Protocol is "rip"
Sending updates every 30 seconds, next due in 13 seconds
Invalid after 180 seconds, hold down 180, flushed after 240
Outgoing update filter list for all interfaces is not set
Incoming update filter list for all interfaces is not set
Redistributing: rip
Default version control: send version 2, receive 2
Interface Send Recv Triggered RIP Key-chain
Vlan1 2 2
FastEthernet0/0 2 2
Serial0/0/1 2 2
Serial0/1/0 2 2
Serial0/0/0 2 2
Automatic network summarization is not in effect
Maximum path: 4
Routing for Networks:
10.0.0.0
Passive Interface(s):
Routing Information Sources:
Gateway Distance Last Update
10.1.5.2 120 00:00:05
10.1.3.2 120 00:00:12
10.1.2.2 120 00:00:12
10.1.4.2 120 00:00:17
Distance: (default is 120)
corp#
debug eigrp packet
break into two columns for readability
Observations:
There doesnt appear to be a pattern in the order each router is addressed, except that the TO's and FROM"s are grouped together
The TO messages dont show the destination IP, only the egress local interface
The FROM messages do show the remote IP, as well as the local ingress interface
Corp#
EIGRP: Received HELLO on FastEthernet0/0 nbr 10.1.5.2
AS 10, Flags 0x0, Seq 18/0 idbQ 0/0
hello from R3
Corp#
EIGRP: Received HELLO on Serial0/1/0 nbr 10.1.4.2
AS 10, Flags 0x0, Seq 16/0 idbQ 0/0
hello from R2
Corp#
EIGRP: Received HELLO on Serial0/0/0 nbr 10.1.2.2
AS 10, Flags 0x0, Seq 19/0 idbQ 0/0
hello from R1
------------------------------------------------------------
Corp#
EIGRP: Sending HELLO on Serial0/1/0
AS 10, Flags 0x0, Seq 21/0 idbQ 0/0 iidbQ un/rely 0/0
hello to R2
Corp#
EIGRP: Sending HELLO on FastEthernet0/0
AS 10, Flags 0x0, Seq 21/0 idbQ 0/0 iidbQ un/rely 0/0
hello to R3
Corp#
EIGRP: Sending HELLO on Serial0/0/1
AS 10, Flags 0x0, Seq 21/0 idbQ 0/0 iidbQ un/rely 0/0
hello to R1
Corp#
EIGRP: Sending HELLO on Serial0/0/0
AS 10, Flags 0x0, Seq 21/0 idbQ 0/0 iidbQ un/rely 0/0
hello to R1
Corp#
EIGRP: Sending HELLO on Vlan1
AS 10, Flags 0x0, Seq 21/0 idbQ 0/0 iidbQ un/rely 0/0
hello to switch card (not a router....)
------------------------------------------------------------
Corp#
EIGRP: Received HELLO on Serial0/0/1 nbr 10.1.3.2
AS 10, Flags 0x0, Seq 19/0 idbQ 0/0
hello from R1
Corp#
EIGRP: Received HELLO on FastEthernet0/0 nbr 10.1.5.2
AS 10, Flags 0x0, Seq 18/0 idbQ 0/0
hello from R3
Corp#
EIGRP: Received HELLO on Serial0/0/0 nbr 10.1.2.2
AS 10, Flags 0x0, Seq 19/0 idbQ 0/0
hello from R1
Corp#
EIGRP: Received HELLO on Serial0/1/0 nbr 10.1.4.2
AS 10, Flags 0x0, Seq 16/0 idbQ 0/0
hello from R2
------------------------------------------------------------
Corp#
EIGRP: Sending HELLO on Serial0/1/0
AS 10, Flags 0x0, Seq 21/0 idbQ 0/0 iidbQ un/rely 0/0
hello to R2... no neighbor IP?
Corp#
EIGRP: Sending HELLO on Serial0/0/0
AS 10, Flags 0x0, Seq 21/0 idbQ 0/0 iidbQ un/rely 0/0
hello to R1... no neighbor IP?
Corp#
EIGRP: Sending HELLO on FastEthernet0/0
AS 10, Flags 0x0, Seq 21/0 idbQ 0/0 iidbQ un/rely 0/0
hello to R3... no neighbor IP?
Corp#
EIGRP: Sending HELLO on Serial0/0/1
AS 10, Flags 0x0, Seq 21/0 idbQ 0/0 iidbQ un/rely 0/0
hello to R1
Corp#
EIGRP: Sending HELLO on Vlan1
AS 10, Flags 0x0, Seq 21/0 idbQ 0/0 iidbQ un/rely 0/0
hello to switch card (not a router)
------------------------------------------------------------
OUTPUT CONTINUES IN NEXT COLUMN
Corp#
EIGRP: Received HELLO on Serial0/0/1 nbr 10.1.3.2
AS 10, Flags 0x0, Seq 19/0 idbQ 0/0
hello from R1
Corp#
EIGRP: Received HELLO on FastEthernet0/0 nbr 10.1.5.2
AS 10, Flags 0x0, Seq 18/0 idbQ 0/0
hello from R3
Corp#
EIGRP: Received HELLO on Serial0/0/0 nbr 10.1.2.2
AS 10, Flags 0x0, Seq 19/0 idbQ 0/0
hello from R1
Corp#
EIGRP: Received HELLO on Serial0/1/0 nbr 10.1.4.2
AS 10, Flags 0x0, Seq 16/0 idbQ 0/0
hello from R2
------------------------------------------------------------
Corp#
EIGRP: Sending HELLO on Serial0/1/0
AS 10, Flags 0x0, Seq 21/0 idbQ 0/0 iidbQ un/rely 0/0
hello to R2
Corp#
EIGRP: Sending HELLO on Serial0/0/0
AS 10, Flags 0x0, Seq 21/0 idbQ 0/0 iidbQ un/rely 0/0
hello to R1
Corp#
EIGRP: Sending HELLO on Vlan1
AS 10, Flags 0x0, Seq 21/0 idbQ 0/0 iidbQ un/rely 0/0
hello to Corp switchcard
Corp#
EIGRP: Sending HELLO on Serial0/0/1
AS 10, Flags 0x0, Seq 21/0 idbQ 0/0 iidbQ un/rely 0/0
hello to R1
Corp#
EIGRP: Sending HELLO on FastEthernet0/0
AS 10, Flags 0x0, Seq 21/0 idbQ 0/0 iidbQ un/rely 0/0
hello to R3... no neighbor IP?
------------------------------------------------------------
Corp#
EIGRP: Received HELLO on Serial0/0/1 nbr 10.1.3.2
AS 10, Flags 0x0, Seq 19/0 idbQ 0/0
hello from R1
Corp#
EIGRP: Received HELLO on FastEthernet0/0 nbr 10.1.5.2
AS 10, Flags 0x0, Seq 18/0 idbQ 0/0
hello from R3
Corp#
EIGRP: Received HELLO on Serial0/1/0 nbr 10.1.4.2
AS 10, Flags 0x0, Seq 16/0 idbQ 0/0
hello from R2
Corp#
EIGRP: Received HELLO on Serial0/0/0 nbr 10.1.2.2
AS 10, Flags 0x0, Seq 19/0 idbQ 0/0
hello from R1
------------------------------------------------------------
Corp#
EIGRP: Sending HELLO on Serial0/1/0
AS 10, Flags 0x0, Seq 21/0 idbQ 0/0 iidbQ un/rely 0/0
hello to R2
Corp#
EIGRP: Sending HELLO on Vlan1
AS 10, Flags 0x0, Seq 21/0 idbQ 0/0 iidbQ un/rely 0/0
hello to Corp switchcard
EIGRP: Sending HELLO on Serial0/0/0
AS 10, Flags 0x0, Seq 21/0 idbQ 0/0 iidbQ un/rely 0/0
hello to R1
EIGRP: Sending HELLO on Serial0/0/1
AS 10, Flags 0x0, Seq 21/0 idbQ 0/0 iidbQ un/rely 0/0
hello to R1
Corp#
EIGRP: Sending HELLO on FastEthernet0/0
AS 10, Flags 0x0, Seq 21/0 idbQ 0/0 iidbQ un/rely 0/0
hello to R3
------------------------------------------------------------
Now some videos. To reinforce EIGRP concepts, and lead into OSPF
OSPF - OPEN SHORTEST PATH FIRST
Before enabling OSPF, we'll turn off RIP and EIGRP on all four routers.
Device(config)#
no router eigrp 10
Device(config)#
no router rip
The OSPF configs for the local egress ip address
Corp(config)#
router ospf 132
Corp(config)#
network 10.1.0.0 0.0.255.255 area 0
R1(config)#
router ospf 1
R1(config)#
network 10.1.0.0 0.0.255.255 area 0
R1(config)#
network 192.168.0.0 0.0.255.255 area 0
R2(config)#
router ospf 45678
R2(config)#
network 10.0.0.0 0.0.0.255 area 0
R2(config)#
network 192.168.30.1 0.0.0.0 area 0
R2(config)#
network 192.168.40.1 0.0.0.0 area 0
all 32 bits of the mask are specified for the 192 entries;
these are not network id's, they are HOST id's of the specific interfaces, which are EGRESS interfaces on the router we are configuring
R3(config)#
router ospf 1
R2(config)#
network 10.1.5.2 0.0.0.255 area 0
R2(config)#
network 172.16.10.0 0.0.0.255 area 0
Wildcard Masks
these notes are not intended to be a precise explanation of wlidcard masking, but rather a look into my thought process as I am learning the concept.
resources:
traceroute blog examples
routerjockey blog examples
subnetonline wildcard calculator
Ch 9 Exam Essentials
1. Know EIGRP features
classless (like RipV2 and OSPF)
distance vector
supports IP, IPX, appleTalk, IPV6
supports summaries and discontiguous networks
uses the Diffusing Update Algorithm (DUAL) to maintain route information
uses RTP to communicate with other EIGRP routers
uses the concept of an autonomous system to describe the set of contiguous routers that run the same routing protocol and share routing information
considered CLASSLESS- includes the subnet mask in its route updates
sends traditional distance-vector updates containing info about networks plus the cost of reaching them from the perspective of the advertising router
but not strictly distance-vector. Has link-state characteristics: synchronizes routing tables between neighbors at startup and then sends specific updates only when topology changes.
max hop count of 255 (default is 100)
but hop count is NOT a metric, like in RIP. Hop count is how many routers an EIGRP route update can traverse before being discarded. This limits the size of the AS.
2. Know how to configure EIGRP
the router eigrp [as] command turns EIGRP routing on in the router. Unlike RIPv1, EIGRP uses classless routing. BUT you can still configure as classful.
R1(config)#
router eigrp 10
enters router config mode
R1(config-router)#
network 10.0.0.0
on this router, interfaces that fall within 10.0.0.0 will advertise EIGRP info
3. Know how to verify EIGRP operation
Corp#
show ip
protocols
Corp#
show ip
route
Corp#
show ip
route eigrp
Corp#
show ip
eigrp neighbors
Corp#
show ip
eigrp topology
Corp#
show ip
eigrp interfaces
Corp#
show ip
protocols
info about all active routing protocols
Routing Protocol is "eigrp 10 "
Outgoing update filter list for all interfaces is not set
Incoming update filter list for all interfaces is not set
Default networks flagged in outgoing updates
Default networks accepted from incoming updates
Redistributing: eigrp 10
EIGRP-IPv4 Protocol for AS(10)
Metric weight K1=1, K2=0, K3=1, K4=0, K5=0
NSF-aware route hold timer is 240
Router-ID: 10.1.1.1
Topology : 0 (base)
Active Timer: 3 min
Distance: internal 90 external 170
Maximum path: 4
Maximum hopcount 100
Maximum metric variance 1
Automatic Summarization: disabled
Automatic address summarization:
Maximum path: 4
Routing for Networks:
10.0.0.0
Routing Information Sources:
Gateway Distance Last Update
10.1.2.2 90 200105
10.1.3.2 90 200113
10.1.4.2 90 254351
10.1.5.2 90 303742
Distance: internal 90 external 170
Corp#
show ip
protocols
(continued)
Routing Protocol is "rip"
Sending updates every 30 seconds, next due in 6 seconds
Invalid after 180 seconds, hold down 180, flushed after 240
Outgoing update filter list for all interfaces is not set
Incoming update filter list for all interfaces is not set
Redistributing: rip
Default version control: send version 2, receive 2
Interface Send Recv Triggered RIP Key-chain
Vlan1 2 2
FastEthernet0/0 2 2
Serial0/1/0 2 2
Serial0/0/1 2 2
Serial0/0/0 2 2
Automatic network summarization is not in effect
Maximum path: 4
Routing for Networks:
10.0.0.0
Passive Interface(s):
Routing Information Sources:
Gateway Distance Last Update
10.1.5.2 120 00:00:15
10.1.3.2 120 00:00:01
10.1.2.2 120 00:00:01
10.1.4.2 120 00:00:17
Distance: (default is 120)
Corp#
show ip
route
entire routing table
Codes: L - local, C - connected, S - static, R - RIP, M - mobile, B - BGP
D - EIGRP, EX - EIGRP external, O - OSPF, IA - OSPF inter area
N1 - OSPF NSSA external type 1, N2 - OSPF NSSA external type 2
E1 - OSPF external type 1, E2 - OSPF external type 2, E - EGP
i - IS-IS, L1 - IS-IS level-1, L2 - IS-IS level-2, ia - IS-IS inter area
* - candidate default, U - per-user static route, o - ODR
P - periodic downloaded static route
Gateway of last resort is not set
10.0.0.0/8 is variably subnetted, 10 subnets, 2 masks
C 10.1.1.0/24 is directly connected, Vlan1
L 10.1.1.1/32 is directly connected, Vlan1
C 10.1.2.0/24 is directly connected, Serial0/0/0
L 10.1.2.1/32 is directly connected, Serial0/0/0
C 10.1.3.0/24 is directly connected, Serial0/0/1
L 10.1.3.1/32 is directly connected, Serial0/0/1
C 10.1.4.0/24 is directly connected, Serial0/1/0
L 10.1.4.1/32 is directly connected, Serial0/1/0
C 10.1.5.0/24 is directly connected, FastEthernet0/0
L 10.1.5.1/32 is directly connected, FastEthernet0/0
172.16.0.0/16 is variably subnetted, 2 subnets, 2 masks
R 172.16.0.0/16 [120/1] via 10.1.5.2, 00:00:14, FastEthernet0/0
D 172.16.10.0/24 [90/28160] via 10.1.5.2, 00:07:23, FastEthernet0/0
D 192.168.10.0/24 [90/2172416] via 10.1.3.2, 00:09:13, Serial0/0/1
[90/2172416] via 10.1.2.2, 00:09:13, Serial0/0/0
D 192.168.20.0/24 [90/2172416] via 10.1.3.2, 00:09:13, Serial0/0/1
[90/2172416] via 10.1.2.2, 00:09:13, Serial0/0/0
D 192.168.30.0/24 [90/2172416] via 10.1.4.2, 00:08:59, Serial0/1/0
D 192.168.40.0/24 [90/2172416] via 10.1.4.2, 00:08:59, Serial0/1/0
Shows the entire routing table
Corp#
show ip
eigrp toplogy
all nets the Corp router can see, including on the other side of other routers
IP-EIGRP Topology Table for AS 10/ID(10.1.5.1)
Codes: P - Passive, A - Active, U - Update, Q - Query, R - Reply,
r - Reply status
directly connected via local egress interface
P 10.1.1.0/24, 1 successors, FD is 25625600
via Connected, Vlan1
P 10.1.2.0/24, 1 successors, FD is 2169856
via Connected, Serial0/0/0
P 10.1.3.0/24, 1 successors, FD is 2169856
via Connected, Serial0/0/1
P 10.1.4.0/24, 1 successors, FD is 2169856
via Connected, Serial0/1/0
P 10.1.5.0/24, 1 successors, FD is 28160
via Connected, FastEthernet0/0
remotely connected via remote ingress ip address
P 172.16.10.0/24, 1 successors, FD is 28160
via 10.1.5.2 (28160/25600), FastEthernet0/0
P 192.168.10.0/24, 2 successors, FD is 2172416
via 10.1.3.2 (2172416/28160), Serial0/0/1
via 10.1.2.2 (2172416/28160), Serial0/0/0
P 192.168.20.0/24, 2 successors, FD is 2172416
via 10.1.3.2 (2172416/28160), Serial0/0/1
via 10.1.2.2 (2172416/28160), Serial0/0/0
P 192.168.30.0/24, 1 successors, FD is 2172416
via 10.1.4.2 (2172416/28160), Serial0/1/0
P 192.168.40.0/24, 1 successors, FD is 2172416
via 10.1.4.2 (2172416/28160), Serial0/1/0
Corp#
show ip
eigrp interfaces
local interfaces on Corp, with peer data, 5 total, including VLAN1 (0 peers, no router on this network)
IP-EIGRP interfaces for process 10
Xmit Queue Mean Pacing Time Multicast Pending
Interface Peers Un/Reliable SRTT Un/Reliable Flow Timer Routes
Vlan 0 0/0 1236 0/10 0 0
Fa0/0 1 0/0 1236 0/10 0 0
Se0/0/1 1 0/0 1236 0/10 0 0
Se0/1/0 1 0/0 1236 0/10 0 0
Se0/0/0 1 0/0 1236 0/10 0 0
Corp#
show ip
eigrp neighbors
remote interfaces on the 4 neighboring routers
IP-EIGRP neighbors for process 10
H Address Interface Hold Uptime SRTT RTO Q Seq
(sec) (ms) Cnt Num
0 10.1.2.2 Se0/0/0 14 00:54:33 40 1000 0 58
1 10.1.3.2 Se0/0/1 10 00:54:33 40 1000 0 57
2 10.1.4.2 Se0/1/0 14 00:53:38 40 1000 0 51
3 10.1.5.2 Fa0/0 11 00:52:49 40 1000 0 33
4. Compare OSPF and RIPv1
RIPv1 is distance-vector and supports only classful routing. No VLSM
OSPF is link-state and supports VLSM and classless routing
5. Know how OSPF routers become neighboars and/or adjacent
they become neighbors when they see eachother's hello packets.
area id must match, links must be on the same subnet, hello/dead timers must be the same.
OSPF only shares routes with neigbors who have also established adjacencies. NOT ALL NEIGHBORS become adjacent.
When an OSPF router first receives a hello packet, it verifies that the data in some fields matches its own locally configured information.
Should any of the checked data be different, the hello packet is discarded and not processed. The data fields verified are the Area ID,
Authentication, Network Mask (on broadcast networks), Hello Interval, Router Dead Interval, and Options fields. If this information doesn’t match,
then neighborship is stuck in the down stage.
packetpushers.net
6. Be able to configure single-area OSPF
two commands:
router ospf [process id]
network x.x.x.x y.y.y.y area z
7. Be able to verify the operation of OSPF
Corp#
show ip
protocols
Corp#
show ip
route
Corp#
show ip
ospf
Corp#
show ip
ospf database
Corp#
show ip
ospf interface
Corp#
show ip
ospf neighbor
IOS 15.1
Corp#
show ip
protocols
Routing Protocol is "ospf 132"
Outgoing update filter list for all interfaces is not set
Incoming update filter list for all interfaces is not set
Router ID 10.1.5.1
Number of areas in this router is 1. 1 normal 0 stub 0 nssa
Maximum path: 4
Routing for Networks:
10.1.0.0 0.0.255.255 area 0
Routing Information Sources:
Gateway Distance Last Update
10.1.5.1 110 00:08:51
172.16.10.1 110 00:08:51
192.168.20.1 110 00:12:53
192.168.40.1 110 00:09:35
Distance: (default is 110)
IOS 15.1
Corp#
show ip
route
10.0.0.0/8 is variably subnetted, 10 subnets, 2 masks
C 10.1.1.0/24 is directly connected, Vlan1
L 10.1.1.1/32 is directly connected, Vlan1
C 10.1.2.0/24 is directly connected, Serial0/0/0
L 10.1.2.1/32 is directly connected, Serial0/0/0
C 10.1.3.0/24 is directly connected, Serial0/0/1
L 10.1.3.1/32 is directly connected, Serial0/0/1
C 10.1.4.0/24 is directly connected, Serial0/1/0
L 10.1.4.1/32 is directly connected, Serial0/1/0
C 10.1.5.0/24 is directly connected, FastEthernet0/0
L 10.1.5.1/32 is directly connected, FastEthernet0/0
172.16.0.0/24 is subnetted, 1 subnets
O 172.16.10.0/24 [110/10] via 10.1.5.2, 00:09:09, FastEthernet0/0
O 192.168.10.0/24 [110/65] via 10.1.2.2, 00:13:11, Serial0/0/0
O 192.168.20.0/24 [110/65] via 10.1.2.2, 00:13:01, Serial0/0/0
O 192.168.30.0/24 [110/65] via 10.1.4.2, 00:09:54, Serial0/1/0
O 192.168.40.0/24 [110/65] via 10.1.4.2, 00:09:54, Serial0/1/0
IOS 15.1
Corp#
show ip
ospf
Routing Process "ospf 132" with ID 10.1.5.1
Supports only single TOS(TOS0) routes
Supports opaque LSA
SPF schedule delay 5 secs, Hold time between two SPFs 10 secs
Minimum LSA interval 5 secs. Minimum LSA arrival 1 secs
Number of external LSA 0. Checksum Sum 0x000000
Number of opaque AS LSA 0. Checksum Sum 0x000000
Number of DCbitless external and opaque AS LSA 0
Number of DoNotAge external and opaque AS LSA 0
Number of areas in this router is 1. 1 normal 0 stub 0 nssa
External flood list length 0
Area BACKBONE(0)
Number of interfaces in this area is 5
Area has no authentication
SPF algorithm executed 7 times
Area ranges are
Number of LSA 5. Checksum Sum 0x034486
Number of opaque link LSA 0. Checksum Sum 0x000000
Number of DCbitless LSA 0
Number of indication LSA 0
Number of DoNotAge LSA 0
Flood list length 0
IOS 15.1
Corp#
show ip
ospf database
OSPF Router with ID (10.1.5.1) (Process ID 132)
Router Link States (Area 0)
Link ID ADV Router Age Seq# Checksum Link count
192.168.20.1 192.168.20.1 854 0x80000006 0x00ae08 6
192.168.40.1 192.168.40.1 656 0x80000004 0x006bc6 4
10.1.5.1 10.1.5.1 612 0x8000000f 0x00ab77 8
172.16.10.1 172.16.10.1 612 0x80000003 0x00b30d 2
Net Link States (Area 0)
Link ID ADV Router Age Seq# Checksum
10.1.5.1 10.1.5.1 612 0x80000001 0x00cc34
ADV Router aka RID/Router ID, the highest IP address on the router
we are seeing three connected routers + our own router (Corp at 10.1.5.1)
IOS 15.1
Corp#
show ip
ospf interface
Vlan1 is up, line protocol is up
Internet address is 10.1.1.1/24, Area 0
Process ID 132, Router ID 10.1.5.1, Network Type BROADCAST, Cost: 1
Transmit Delay is 1 sec, State DR, Priority 1
Designated Router (ID) 10.1.5.1, Interface address 10.1.1.1
No backup designated router on this network
Timer intervals configured, Hello 10, Dead 40, Wait 40, Retransmit 5
Hello due in 00:00:08
Index 1/1, flood queue length 0
Next 0x0(0)/0x0(0)
Last flood scan length is 1, maximum is 1
Last flood scan time is 0 msec, maximum is 0 msec
Neighbor Count is 0, Adjacent neighbor count is 0
Suppress hello for 0 neighbor(s)
FastEthernet0/0 is up, line protocol is up
Internet address is 10.1.5.1/24, Area 0
Process ID 132, Router ID 10.1.5.1, Network Type BROADCAST, Cost: 1
Transmit Delay is 1 sec, State DR, Priority 1
Designated Router (ID) 10.1.5.1, Interface address 10.1.5.1
Backup Designated Router (ID) 172.16.10.1, Interface address 10.1.5.2
Timer intervals configured, Hello 10, Dead 40, Wait 40, Retransmit 5
Hello due in 00:00:07
Index 2/2, flood queue length 0
Next 0x0(0)/0x0(0)
Last flood scan length is 1, maximum is 1
Last flood scan time is 0 msec, maximum is 0 msec
Neighbor Count is 1, Adjacent neighbor count is 1
Adjacent with neighbor 172.16.10.1 (Backup Designated Router)
Suppress hello for 0 neighbor(s)
Serial0/0/1 is up, line protocol is up
Internet address is 10.1.3.1/24, Area 0
Process ID 132, Router ID 10.1.5.1, Network Type POINT-TO-POINT, Cost: 64
Transmit Delay is 1 sec, State POINT-TO-POINT,
Timer intervals configured, Hello 10, Dead 40, Wait 40, Retransmit 5
Hello due in 00:00:07
Index 3/3, flood queue length 0
Next 0x0(0)/0x0(0)
Last flood scan length is 1, maximum is 1
Last flood scan time is 0 msec, maximum is 0 msec
Neighbor Count is 1 , Adjacent neighbor count is 1
Adjacent with neighbor 192.168.20.1
Suppress hello for 0 neighbor(s)
Serial0/1/0 is up, line protocol is up
Internet address is 10.1.4.1/24, Area 0
Process ID 132, Router ID 10.1.5.1, Network Type POINT-TO-POINT, Cost: 64
Transmit Delay is 1 sec, State POINT-TO-POINT,
Timer intervals configured, Hello 10, Dead 40, Wait 40, Retransmit 5
Hello due in 00:00:07
Index 4/4, flood queue length 0
Next 0x0(0)/0x0(0)
Last flood scan length is 1, maximum is 1
Last flood scan time is 0 msec, maximum is 0 msec
Neighbor Count is 1 , Adjacent neighbor count is 1
Adjacent with neighbor 192.168.40.1
Suppress hello for 0 neighbor(s)
Serial0/0/0 is up, line protocol is up
Internet address is 10.1.2.1/24, Area 0
Process ID 132, Router ID 10.1.5.1, Network Type POINT-TO-POINT, Cost: 64
Transmit Delay is 1 sec, State POINT-TO-POINT,
Timer intervals configured, Hello 10, Dead 40, Wait 40, Retransmit 5
Hello due in 00:00:07
Index 5/5, flood queue length 0
Next 0x0(0)/0x0(0)
Last flood scan length is 1, maximum is 1
Last flood scan time is 0 msec, maximum is 0 msec
Neighbor Count is 1 , Adjacent neighbor count is 1
Adjacent with neighbor 192.168.20.1
Suppress hello for 0 neighbor(s)
IOS 15.1
Corp#
show ip
ospf neighbor
Neighbor ID Pri State Dead Time Address Interface
192.168.20.1 0 FULL/ - 00:00:31 10.1.3.2 Serial0/0/1
192.168.40.1 0 FULL/ - 00:00:33 10.1.4.2 Serial0/1/0
192.168.20.1 0 FULL/ - 00:00:31 10.1.2.2 Serial0/0/0
172.16.10.1 1 FULL/BDR 00:00:32 10.1.5.2 FastEthernet0/0
Flashcards
Chapter 9 Written Lab 9.0
1. What four routed protocols are supported by EIGRP?
IPX, IPv4, IPv6, AppleTalk
2. When is redistribution required for EIGRP?
when there are multiple autonomous systems
redistribution is required when more than one EIGRP session or process is running and they are identified with different ASNs.
redistribution shares toplogy information between EIGRP sessions
3. What command would be used to enable EIGRP with an autonmous system number of 300?
router eigrp 300
4. What command will tell EIGRP that it is connected to network 172.10.0.0?
network 172.10.0.0
5. What type of EIGRP interface will neither send nor receive Hello packets?
passive-interface s0/0
6. Write the command that will enable OSPF process 101 on a router
router ospf 101
7. Write the command that will display details of all OSFP routing processes enabled on a router
show ip ospf
8. Write the command that will display interface-specific OSPF information
show ip ospf interface
9. Write the command that will display all OSPF neighbors
show ip ospf neighbor
10. Write the command that will display all different OSPF route types that are currently known by the router
show ip route ospf
Chapter 9 Hands-On Labs
Build the network and configure interfaces
LabA(config)#
int f0/0
LabA(config-if)#
ip addr 172.16.10.1 255.255.255.0
LabA(config-if)#
no shut
LabB(config)#
int f0/0
LabB(config-if)#
ip addr 172.16.10.2 255.255.255.0
LabB(config-if)#
no shut
LabB(config-if)#
int s0/0/0
LabB(config-if)#
ip addr 172.16.20.1 255.255.255.0
LabB(config-if)#
no shut
LabC(config)#
int f0/0
LabC(config-if)#
ip addr 172.16.30.1 255.255.255.0
LabC(config-if)#
no shut
LabC(config-if)#
int s0/0/0
LabC(config-if)#
ip addr 172.16.20.2 255.255.255.0
LabC(config-if)#
no shut
LabC(config-if)#
int s0/0/1
LabC(config-if)#
ip addr 172.16.40.1 255.255.255.0
LabC(config-if)#
no shut
LabD(config)#
int s0/0/0
LabD(config-if)#
ip addr 172.16.40.2 255.255.255.0
LabD(config-if)#
no shut
LabD(config-if)#
int f0/0
LabD(config-if)#
ip addr 172.16.50.1 255.255.255.0
LabD(config-if)#
no shut
9.1 - Configure and Verfiy EIGRP
configure EIGRP on all 4 routers and observe results
LabA
LabA(config)#
router eigrp 100
LabA(config-router)#
net 172.16.0.0
[no output]
LabA#
show ip eigrp neighbors
IP-EIGRP neighbors for process 100
LabA#
show ip eigrp topology
IP-EIGRP Topology Table for AS 100/ID(172.16.10.1)
Codes: P - Passive, A - Active, U - Update, Q - Query, R - Reply,
r - Reply status
P 172.16.10.0/24, 1 successors, FD is 28160
via Connected, FastEthernet0/0
LabA#
show ip eigrp interfaces
IP-EIGRP interfaces for process 100
Xmit Queue Mean Pacing Time Multicast Pending
Interface Peers Un/Reliable SRTT Un/Reliable Flow Timer Routes
Fa0/0 0 0/0 1236 0/10 0 0
no neighbors at this point since EIGRP is only active on this router. One successor AKA route, which is the connection out of this router.
But note that we have no information about what's on the other side of that link
LabB
LabB(config)#
router eigrp 100
LabB(config-router)#
net 172.16.0.0
%DUAL-5-NBRCHANGE: IP-EIGRP 100:
Neighbor 172.16.10.1 (FastEthernet0/0) is up: new adjacency
LabB#
show ip eigrp neighbors
IP-EIGRP neighbors for process 100
H Address Interface Hold Uptime SRTT RTO Q Seq
(sec) (ms) Cnt Num
0 172.16.10.1 Fa0/0 12 00:00:14 40 1000 0 1
LabB#
show ip eigrp topology
IP-EIGRP Topology Table for AS 100/ID(172.16.20.1)
Codes: P - Passive, A - Active, U - Update, Q - Query, R - Reply,
r - Reply status
P 172.16.10.0/24, 1 successors, FD is 28160
via Connected, FastEthernet0/0
P 172.16.20.0/24, 1 successors, FD is 2169856
via Connected, Serial0/0/0
LabB#
show ip eigrp interfaces
IP-EIGRP interfaces for process 100
Xmit Queue Mean Pacing Time Multicast Pending
Interface Peers Un/Reliable SRTT Un/Reliable Flow Timer Routes
Fa0/0 1 0/0 1236 0/10 0 0
Se0/0/0 0 0/0 1236 0/10 0 0
We can see a neighbor at .1
We now have two paths out of this router. Left to neighbor. Exit at right is available as successor(route), but again we have no info about
what is on the other side, since that router has no EIGRP yet (s0/0/0 has no peers, but is an EIGRP interface)
LabC
LabC(config)#
router eigrp 100
LabC(config-router)#
net 172.16.0.0
%DUAL-5-NBRCHANGE: IP-EIGRP 100:
Neighbor 172.16.20.1 (Serial0/0/0) is up: new adjacency
LabC#
show ip eigrp neighbors
IP-EIGRP neighbors for process 100
H Address Interface Hold Uptime SRTT RTO Q Seq
(sec) (ms) Cnt Num
0 172.16.20.1 Se0/0/0 12 00:00:25 40 1000 0 8
LabC#
show ip eigrp toplogy
IP-EIGRP Topology Table for AS 100/ID(172.16.40.1)
Codes: P - Passive, A - Active, U - Update, Q - Query, R - Reply,
r - Reply status
P 172.16.10.0/24, 1 successors, FD is 2172416
via 172.16.20.1 (2172416/28160), Serial0/0/0
P 172.16.20.0/24, 1 successors, FD is 2169856
via Connected, Serial0/0/0
P 172.16.30.0/24, 1 successors, FD is 28160
via Connected, FastEthernet0/0
P 172.16.40.0/24, 1 successors, FD is 2169856
via Connected, Serial0/0/1
LabC#
show ip eigrp interfaces
IP-EIGRP interfaces for process 100
Xmit Queue Mean Pacing Time Multicast Pending
Interface Peers Un/Reliable SRTT Un/Reliable Flow Timer Routes
Fa0/0 0 0/0 1236 0/10 0 0
Se0/0/0 1 0/0 1236 0/10 0 0
Se0/0/1 0 0/0 1236 0/10 0 0
.1 router B interface is now a neighbor.
LabC topology shows the 3 direct connected networks AND the network on the other side of LabB since LabB is our EIGRP neighbor
3 eigrp interfaces:
Fa0/0 is ours at LabC- no peers bc there is no eigrp router on the other end
s0/0/0 is our interface out left to LabB which is an EIGRP peer
s0/0/1 is our interface out right which does not see an EIGRP peer but does put that net 172.16.40.0 in our topology
LabD
LabD(config)#
router eigrp 100
LabD(config-router)#
net 172.16.0.0
%DUAL-5-NBRCHANGE: IP-EIGRP 100:
Neighbor 172.16.40.1 (Serial0/0/0) is up: new adjacency
LabD#
show ip eigrp neighbors
IP-EIGRP neighbors for process 100
H Address Interface Hold Uptime SRTT RTO Q Seq
(sec) (ms) Cnt Num
0 172.16.40.1 Se0/0/0 11 00:00:14 40 1000 0 6
LabD#
show ip eigrp topology
IP-EIGRP Topology Table for AS 100/ID(172.16.50.1)
Codes: P - Passive, A - Active, U - Update, Q - Query, R - Reply,
r - Reply status
P 172.16.10.0/24, 1 successors, FD is 2684416
via 172.16.40.1 (2684416/2172416), Serial0/0/0
P 172.16.20.0/24, 1 successors, FD is 2681856
via 172.16.40.1 (2681856/2169856), Serial0/0/0
P 172.16.30.0/24, 1 successors, FD is 2172416
via 172.16.40.1 (2172416/28160), Serial0/0/0
P 172.16.40.0/24, 1 successors, FD is 2169856
via Connected, Serial0/0/0
P 172.16.50.0/24, 1 successors, FD is 28160
via Connected, FastEthernet0/0
LabD#
show ip eigrp interfaces
IP-EIGRP interfaces for process 100
Xmit Queue Mean Pacing Time Multicast Pending
Interface Peers Un/Reliable SRTT Un/Reliable Flow Timer Routes
Fa0/0 0 0/0 1236 0/10 0 0
Se0/0/0 1 0/0 1236 0/10 0 0
LabC to our left is now a neighbor at 172.16.40.1
toplogy shows a route out to the right (no router on that end)
a route to the left to LabC .40.0
the .10.0, .20.0, and .30.0 networks via info from LabC
2 eigrp interfaces-
fa0/0 out to the right
s0/0/0 out left to LabC
Time to remove EIGRP from all four routers to prepare for the OSPF lab next,
since EIGRP has a lower AD than OSPF
LabA(config)#
no router eigrp 100
LabB(config)#
no router eigrp 100
LabC(config)#
no router eigrp 100
LabD(config)#
no router eigrp 100
9.2 - Enabling the OSPF Process
9.3 - Configuring OSPF Interfaces
9.4 - Verifying OSPF Operation
LabA
LabA(config)#
router ospf 100
LabA(config-router)#
net 172.16.10.1 0.0.0.0 area 0
[no output]
LabA#
show ip ospf neighbor
[no output]
LabA#
show ip ospf database
OSPF Router with ID (172.16.10.1) (Process ID 100)
Router Link States (Area 0)
Link ID ADV Router Age Seq# Checksum Link count
172.16.10.1 172.16.10.1 44 0x80000001 0x00b24b 1
LabA#
show ip ospf interface
FastEthernet0/0 is up, line protocol is up
Internet address is 172.16.10.1/24, Area 0
Process ID 100, Router ID 172.16.10.1, Network Type BROADCAST, Cost: 1
Transmit Delay is 1 sec, State DR, Priority 1
Designated Router (ID) 172.16.10.1, Interface address 172.16.10.1
No backup designated router on this network
Timer intervals configured, Hello 10, Dead 40, Wait 40, Retransmit 5
Hello due in 00:00:08
Index 1/1, flood queue length 0
Next 0x0(0)/0x0(0)
Last flood scan length is 1, maximum is 1
Last flood scan time is 0 msec, maximum is 0 msec
Neighbor Count is 0, Adjacent neighbor count is 0
Suppress hello for 0 neighbor(s)
we're including this router's interface 172.16.10.1 in our ospf area 0
fa0/0 now registers as an ospf interface
the ospf database includes data about this link only.... LabA is counting itself(10.1) as ADVERTISTING router?
the designated router is .1 LabA
LabB
LabB(config)#
router ospf 101
LabB(config-router)#
net 172.16.10.2 0.0.0.0 area 0
LabB(config-router)#
net 172.16.20.1 0.0.0.0 area 0
01:26:36: %OSPF-5-ADJCHG: Process 101, Nbr 172.16.10.1
on FastEthernet0/0 from LOADING to FULL, Loading Done
LabB#
show ip ospf neighbor
Neighbor ID Pri State Dead Time Address Interface
172.16.10.1 1 FULL/DR 00:00:33 172.16.10.1
LabB#
show ip ospf database
OSPF Router with ID (172.16.20.1) (Process ID 101)
Router Link States (Area 0)
Link ID ADV Router Age Seq# Checksum Link count
172.16.10.1 172.16.10.1 145 0x80000002 0x0067cd 1
172.16.20.1 172.16.20.1 32 0x80000003 0x006e8f 2
Net Link States (Area 0)
Link ID ADV Router Age Seq# Checksum
172.16.10.1 172.16.10.1 145 0x80000001 0x00953d
LabB#
show ip ospf interface
FastEthernet0/0 is up, line protocol is up
Internet address is 172.16.10.2/24, Area 0
Process ID 101, Router ID 172.16.20.1, Network Type BROADCAST, Cost: 1
Transmit Delay is 1 sec, State BDR, Priority 1
Designated Router (ID) 172.16.10.1, Interface address 172.16.10.1
Backup Designated Router (ID) 172.16.20.1, Interface address 172.16.10.2
Timer intervals configured, Hello 10, Dead 40, Wait 40, Retransmit 5
Hello due in 00:00:03
Index 1/1, flood queue length 0
Next 0x0(0)/0x0(0)
Last flood scan length is 1, maximum is 1
Last flood scan time is 0 msec, maximum is 0 msec
Neighbor Count is 1, Adjacent neighbor count is 1
Adjacent with neighbor 172.16.10.1 (Designated Router)
Suppress hello for 0 neighbor(s)
Serial0/0/0 is up, line protocol is up
Internet address is 172.16.20.1/24, Area 0
Process ID 101, Router ID 172.16.20.1, Network Type POINT-TO-POINT, Cost: 64
Transmit Delay is 1 sec, State POINT-TO-POINT,
Timer intervals configured, Hello 10, Dead 40, Wait 40, Retransmit 5
Hello due in 00:00:04
Index 2/2, flood queue length 0
Next 0x0(0)/0x0(0)
Last flood scan length is 1, maximum is 1
Last flood scan time is 0 msec, maximum is 0 msec
Suppress hello for 0 neighbor(s)
We've include the two interfaces on this router in the OSPF area
and can now see Router A's interface 10.1 to the left as a neighbor in the area
the "OSPF Database" now shows two links 20.1(local) and 10.1(neighbor) as 'router link states'.
"ADV Router" means advertising router for the two links. The link address is used as the advertising router.
database shows "Net Link States" category with one entry- 172.16.10.1 which is the address of neighbor router to our left
we have two local OSPF interfaces- f0/0 and s0/0/0
LabC
LabC(config)#
router ospf 102
LabC(config-router)#
net 172.16.20.2 0.0.0.0 area 0
LabC(config-router)#
net 172.16.30.1 0.0.0.0 area 0
LabC(config-router)#
net 172.16.40.1 0.0.0.0 area 0
01:33:54: %OSPF-5-ADJCHG: Process 102, Nbr 172.16.20.1
on Serial0/0/0 from LOADING to FULL, Loading Done
LabC#
show ip ospf neighbor
Neighbor ID Pri State Dead Time Address Interface
172.16.20.1 0 FULL/ - 00:00:30 172.16.20.1 Serial0/0/0
LabC#
show ip ospf database
OSPF Router with ID (172.16.40.1) (Process ID 102)
Router Link States (Area 0)
Link ID ADV Router Age Seq# Checksum Link count
172.16.10.1 172.16.10.1 542 0x80000002 0x0067cd 1
172.16.20.1 172.16.20.1 90 0x80000004 0x00a551 3
172.16.40.1 172.16.40.1 37 0x80000004 0x00e47c 4
Net Link States (Area 0)
Link ID ADV Router Age Seq# Checksum
172.16.10.1 172.16.10.1 542 0x80000001 0x00953d
LabC#
show ip ospf interface
Serial0/0/0 is up, line protocol is up
Internet address is 172.16.20.2/24, Area 0
Process ID 102, Router ID 172.16.40.1, Network Type POINT-TO-POINT, Cost: 64
Transmit Delay is 1 sec, State POINT-TO-POINT,
Timer intervals configured, Hello 10, Dead 40, Wait 40, Retransmit 5
Hello due in 00:00:01
Index 1/1, flood queue length 0
Next 0x0(0)/0x0(0)
Last flood scan length is 1, maximum is 1
Last flood scan time is 0 msec, maximum is 0 msec
Neighbor Count is 1 , Adjacent neighbor count is 1
Adjacent with neighbor 172.16.20.1
Suppress hello for 0 neighbor(s)
FastEthernet0/0 is up, line protocol is up
Internet address is 172.16.30.1/24, Area 0
Process ID 102, Router ID 172.16.40.1, Network Type BROADCAST, Cost: 1
Transmit Delay is 1 sec, State DR, Priority 1
Designated Router (ID) 172.16.40.1, Interface address 172.16.30.1
No backup designated router on this network
Timer intervals configured, Hello 10, Dead 40, Wait 40, Retransmit 5
Hello due in 00:00:02
Index 2/2, flood queue length 0
Next 0x0(0)/0x0(0)
Last flood scan length is 1, maximum is 1
Last flood scan time is 0 msec, maximum is 0 msec
Neighbor Count is 0, Adjacent neighbor count is 0
Suppress hello for 0 neighbor(s)
Serial0/0/1 is up, line protocol is up
Internet address is 172.16.40.1/24, Area 0
Process ID 102, Router ID 172.16.40.1, Network Type POINT-TO-POINT, Cost: 64
Transmit Delay is 1 sec, State POINT-TO-POINT,
Timer intervals configured, Hello 10, Dead 40, Wait 40, Retransmit 5
Hello due in 00:00:08
Index 3/3, flood queue length 0
Next 0x0(0)/0x0(0)
Last flood scan length is 1, maximum is 1
Last flood scan time is 0 msec, maximum is 0 msec
Suppress hello for 0 neighbor(s)
we include the three nets conneted to labC in the area.. 20.0, 30.0, and 40.0
link to our left, 20.1 is visible as "Neighbor"
OSPF Database-
Router Link States are
10.1(Router A)
20.1(Router B)
40.1(Router C)(This router)
Net Link States
10.1(Router A)... why does only Router A show here?
Reference- router link state vs net link state
Router Link States are type 1 LSAs. It lists all the routers in the area and the number of interfaces. 40.1 has 4 interfaces
Net Link States are the multi-access networks (Type 2 LSAs). The ADV (advertising router) is the DR.
LabD
LabD(config)#
router ospf 103
LabD(config-router)#
net 172.16.40.2 0.0.0.0 area 0
LabD(config-router)#
net 172.16.50.1 0.0.0.0 area 0
01:37:11: %OSPF-5-ADJCHG: Process 103, Nbr 172.16.40.1
on Serial0/0/0 from LOADING to FULL, Loading Done
LabD#
show ip ospf neighbor
Neighbor ID Pri State Dead Time Address Interface
172.16.40.1 0 FULL/ - 00:00:32 172.16.40.1 Serial0/0/0
LabD#
show ip ospf database
OSPF Router with ID (172.16.50.1) (Process ID 103)
Router Link States (Area 0)
Link ID ADV Router Age Seq# Checksum Link count
172.16.10.1 172.16.10.1 785 0x80000002 0x0067cd 1
172.16.20.1 172.16.20.1 333 0x80000004 0x00a551 3
172.16.40.1 172.16.40.1 111 0x80000005 0x00013b 5
172.16.50.1 172.16.50.1 53 0x80000003 0x001023 3
Net Link States (Area 0)
Link ID ADV Router Age Seq# Checksum
172.16.10.1 172.16.10.1 785 0x80000001 0x00953d
LabD#
show ip ospf interface
Serial0/0/0 is up, line protocol is up
Internet address is 172.16.40.2/24, Area 0
Process ID 103, Router ID 172.16.50.1, Network Type POINT-TO-POINT, Cost: 64
Transmit Delay is 1 sec, State POINT-TO-POINT,
Timer intervals configured, Hello 10, Dead 40, Wait 40, Retransmit 5
Hello due in 00:00:01
Index 1/1, flood queue length 0
Next 0x0(0)/0x0(0)
Last flood scan length is 1, maximum is 1
Last flood scan time is 0 msec, maximum is 0 msec
Neighbor Count is 1 , Adjacent neighbor count is 1
Adjacent with neighbor 172.16.40.1
Suppress hello for 0 neighbor(s)
FastEthernet0/0 is up, line protocol is up
Internet address is 172.16.50.1/24, Area 0
Process ID 103, Router ID 172.16.50.1, Network Type BROADCAST, Cost: 1
Transmit Delay is 1 sec, State WAITING, Priority 1
No designated router on this network
No backup designated router on this network
Timer intervals configured, Hello 10, Dead 40, Wait 40, Retransmit 5
Hello due in 00:00:04
Index 2/2, flood queue length 0
Next 0x0(0)/0x0(0)
Last flood scan length is 1, maximum is 1
Last flood scan time is 0 msec, maximum is 0 msec
Neighbor Count is 0, Adjacent neighbor count is 0
Suppress hello for 0 neighbor(s)
observations
the OSPF databases now match across all 4 routers.
NOTE that this is a database of routers, identified by
router ID. It is not a topology that lists routers AND routes,
like in the "equivalent" eigrp command.show eigrp topology
----------------------------------------------------------------------------------
PAUSE- a tale of a misconfigured network
After a 9 month hiatus, I am reviewing this book and have made it back to Chapter 9. I'm studing this webpage, working thorough the OSPF configurations
described above, and I get stuck on the concept of "link count" under "Router Link States" found in the output of show ip ospf database
The structure of the notes above is helpful, because I was tracking the state of each router BEFORE i made changes to the subsquent router. But just to be sure,
today I decided to recreate the topology, then configure each router one at a time, noting the results as I went.
And I ran into some problems.
Here is the original topology:
And today's recreated toplogy:
After replicating the toplogy and programming the IP addresses on each router, I started on configurations, just like before:
LabA
LabA(config)#
router ospf 100
LabA(config-router)#
net 172.16.10.1 0.0.0.0 area 0
[no output]
LabA#
show ip ospf neighbor
[no output]
LabA#
show ip ospf database
OSPF Router with ID (172.16.10.1) (Process ID 100)
Router Link States (Area 0)
Link ID ADV Router Age Seq# Checksum Link count
172.16.10.1 172.16.10.1 44 0x80000001 0x00b24b 1
LabA#
show ip ospf interface
FastEthernet0/0 is up, line protocol is up
Internet address is 172.16.10.1/24, Area 0
Process ID 100, Router ID 172.16.10.1, Network Type BROADCAST, Cost: 1
Transmit Delay is 1 sec, State DR, Priority 1
Designated Router (ID) 172.16.10.1, Interface address 172.16.10.1
No backup designated router on this network
Timer intervals configured, Hello 10, Dead 40, Wait 40, Retransmit 5
Hello due in 00:00:08
Index 1/1, flood queue length 0
Next 0x0(0)/0x0(0)
Last flood scan length is 1, maximum is 1
Last flood scan time is 0 msec, maximum is 0 msec
Neighbor Count is 0, Adjacent neighbor count is 0
Suppress hello for 0 neighbor(s)
good so far.... On to LabB router
LabB
LabB(config)#
router ospf 101
LabB(config-router)#
net 172.16.10.2 0.0.0.0 area 0
LabB(config-router)#
net 172.16.20.1 0.0.0.0 area 0
01:26:36: %OSPF-5-ADJCHG: Process 101, Nbr 172.16.10.1
on FastEthernet0/0 from LOADING to FULL, Loading Done
LabB#
show ip ospf neighbor
Neighbor ID Pri State Dead Time Address Interface
172.16.10.1 1 FULL/DR 00:00:33 172.16.10.1
LabB#
show ip ospf database
OSPF Router with ID (172.16.20.1) (Process ID 101)
Router Link States (Area 0)
Link ID ADV Router Age Seq# Checksum Link count
172.16.10.1 172.16.10.1 145 0x80000002 0x0067cd 1
172.16.20.1 172.16.20.1 32 0x80000003 0x006e8f 2
Net Link States (Area 0)
Link ID ADV Router Age Seq# Checksum
172.16.10.1 172.16.10.1 145 0x80000001 0x00953d
LabB#
show ip ospf interface
FastEthernet0/0 is up, line protocol is up
Internet address is 172.16.10.2/24, Area 0
Process ID 101, Router ID 172.16.20.1, Network Type BROADCAST, Cost: 1
Transmit Delay is 1 sec, State BDR, Priority 1
Designated Router (ID) 172.16.10.1, Interface address 172.16.10.1
Backup Designated Router (ID) 172.16.20.1, Interface address 172.16.10.2
Timer intervals configured, Hello 10, Dead 40, Wait 40, Retransmit 5
Hello due in 00:00:03
Index 1/1, flood queue length 0
Next 0x0(0)/0x0(0)
Last flood scan length is 1, maximum is 1
Last flood scan time is 0 msec, maximum is 0 msec
Neighbor Count is 1, Adjacent neighbor count is 1
Adjacent with neighbor 172.16.10.1 (Designated Router)
Suppress hello for 0 neighbor(s)
Serial0/0/0 is up, line protocol is up
Internet address is 172.16.20.1/24, Area 0
Process ID 101, Router ID 172.16.20.1, Network Type POINT-TO-POINT, Cost: 64
Transmit Delay is 1 sec, State POINT-TO-POINT,
Timer intervals configured, Hello 10, Dead 40, Wait 40, Retransmit 5
Hello due in 00:00:04
Index 2/2, flood queue length 0
Next 0x0(0)/0x0(0)
Last flood scan length is 1, maximum is 1
Last flood scan time is 0 msec, maximum is 0 msec
Suppress hello for 0 neighbor(s)
still looks good; same as before.... On to LabC router
LabC
LabC(config)#
router ospf 102
LabC(config-router)#
net 172.16.20.2 0.0.0.0 area 0
LabC(config-router)#
net 172.16.30.1 0.0.0.0 area 0
LabC(config-router)#
net 172.16.40.1 0.0.0.0 area 0
01:33:54: %OSPF-5-ADJCHG: Process 102, Nbr 172.16.20.1
on Serial0/0/0 from LOADING to FULL, Loading Done
LabC#
show ip ospf neighbor
[no output]
And here is where I ran into trouble. The show ip ospf neighbor command returns nothing. How can
that be?
After awhile I realized it is due to a misconfiguration in the topology.
For Lab C, I programmed the interfaces as follows:
LabC(config)#
int f0/0
LabC(config-if)#
ip addr 172.16.30.1 255.255.255.0
LabC(config-if)#
no shut
LabC(config-if)#
int s0/0/0
LabC(config-if)#
ip addr 172.16.20.2 255.255.255.0
LabC(config-if)#
no shut
LabC(config-if)#
int s0/0/1
LabC(config-if)#
ip addr 172.16.40.1 255.255.255.0
LabC(config-if)#
no shut
and again here is the topology for that router:
but here is what it SHOULD HAVE looked like (as it did the first time I built it)
S0/0/0 and S0/0/1 are swapped. When I gave the IP 172.16.20.2 to s/0/0/0, thinking that was the interface on the left side
which faces Lab B, I was actually giving 172.16.20.2 to the right side, facing LabC (which has no OSPF configs yet.)
Since the left side got got the IP intended for the right side which was 172.16.40.1
the inverse also occured-
the right side got the IP intended for the left which was 172.16.20.2
LabC left side should have been
s0/0/0 with 20.2
and LabC right side should have been
s0/0/1 with 40.1
The correct IPs were mapped to the correct interfaces. But the mistake happened before I even programmed them.
When I made the connections from LabB to LabC and from LabD to LabC, I plugged then into the wrong ports.
Interestingly.. not only is this causing OSPF to not see B as a neighbor from C.. but B and C cannot ping eachother either.
@B the config is 172.16.20.1/24 @ S0/0/0
@C the config is 172.16.40.1/24 @ S/0/0/1
meaning they are not even on the same network! But the system is not throwing any errors or bringing it to my attention.
It just fails to connect.
To correct the issue, I simply deleted those two links and re-created them. Worth noting, I used the auto select cable here,
which does not ask which interface you want to use when attaching. Earlier I must have plugged the right side first, and
auto select plugged into 0/0/0.
This time I plugged into left side first.
Now LabC OSPF data is reading out correctly...
LabC
LabC(config)#
router ospf 102
LabC(config-router)#
net 172.16.20.2 0.0.0.0 area 0
LabC(config-router)#
net 172.16.30.1 0.0.0.0 area 0
LabC(config-router)#
net 172.16.40.1 0.0.0.0 area 0
01:33:54: %OSPF-5-ADJCHG: Process 102, Nbr 172.16.20.1
on Serial0/0/0 from LOADING to FULL, Loading Done
LabC#
show ip ospf neighbor
Neighbor ID Pri State Dead Time Address Interface
172.16.20.1 0 FULL/ - 00:00:30 172.16.20.1 Serial0/0/0
LabC#
show ip ospf database
OSPF Router with ID (172.16.40.1) (Process ID 102)
Router Link States (Area 0)
Link ID ADV Router Age Seq# Checksum Link count
172.16.10.1 172.16.10.1 542 0x80000002 0x0067cd 1
172.16.20.1 172.16.20.1 90 0x80000004 0x00a551 3
172.16.40.1 172.16.40.1 37 0x80000004 0x00e47c 4
Net Link States (Area 0)
Link ID ADV Router Age Seq# Checksum
172.16.10.1 172.16.10.1 542 0x80000001 0x00953d
LabC#
show ip ospf interface
Serial0/0/0 is up, line protocol is up
Internet address is 172.16.20.2/24, Area 0
Process ID 102, Router ID 172.16.40.1, Network Type POINT-TO-POINT, Cost: 64
Transmit Delay is 1 sec, State POINT-TO-POINT,
Timer intervals configured, Hello 10, Dead 40, Wait 40, Retransmit 5
Hello due in 00:00:01
Index 1/1, flood queue length 0
Next 0x0(0)/0x0(0)
Last flood scan length is 1, maximum is 1
Last flood scan time is 0 msec, maximum is 0 msec
Neighbor Count is 1 , Adjacent neighbor count is 1
Adjacent with neighbor 172.16.20.1
Suppress hello for 0 neighbor(s)
FastEthernet0/0 is up, line protocol is up
Internet address is 172.16.30.1/24, Area 0
Process ID 102, Router ID 172.16.40.1, Network Type BROADCAST, Cost: 1
Transmit Delay is 1 sec, State DR, Priority 1
Designated Router (ID) 172.16.40.1, Interface address 172.16.30.1
No backup designated router on this network
Timer intervals configured, Hello 10, Dead 40, Wait 40, Retransmit 5
Hello due in 00:00:02
Index 2/2, flood queue length 0
Next 0x0(0)/0x0(0)
Last flood scan length is 1, maximum is 1
Last flood scan time is 0 msec, maximum is 0 msec
Neighbor Count is 0, Adjacent neighbor count is 0
Suppress hello for 0 neighbor(s)
Serial0/0/1 is up, line protocol is up
Internet address is 172.16.40.1/24, Area 0
Process ID 102, Router ID 172.16.40.1, Network Type POINT-TO-POINT, Cost: 64
Transmit Delay is 1 sec, State POINT-TO-POINT,
Timer intervals configured, Hello 10, Dead 40, Wait 40, Retransmit 5
Hello due in 00:00:08
Index 3/3, flood queue length 0
Next 0x0(0)/0x0(0)
Last flood scan length is 1, maximum is 1
Last flood scan time is 0 msec, maximum is 0 msec
Suppress hello for 0 neighbor(s)
Which brings me to the original reason I re-created this topology... I was confused about the LINK COUNTS
here:
OSPF Router with ID (172.16.40.1) (Process ID 102)
Router Link States (Area 0)
Link ID ADV Router Age Seq# Checksum Link count
172.16.10.1 172.16.10.1 542 0x80000002 0x0067cd 1
172.16.20.1 172.16.20.1 90 0x80000004 0x00a551 3
172.16.40.1 172.16.40.1 37 0x80000004 0x00e47c 4
Net Link States (Area 0)
Link ID ADV Router Age Seq# Checksum
172.16.10.1 172.16.10.1 542 0x80000001 0x00953d
The steps of recreating the lab were helpful, but this link answered the question:
Here is the output of each router's command show ip ospf interface as they are
set up one at a time.
LabA - No OSPF at B, C, or D yet
show ip ospf database
OSPF Router with ID (172.16.10.1) (Process ID 100)
Router Link States (Area 0)
Link ID ADV Router Age Seq# Checksum Link count
172.16.10.1 172.16.10.1 44 0x80000001 0x00b24b 1
LabB - No OSPF at C or D yet
show ip ospf database
OSPF Router with ID (172.16.20.1) (Process ID 101)
Router Link States (Area 0)
Link ID ADV Router Age Seq# Checksum Link count
172.16.10.1 172.16.10.1 145 0x80000002 0x0067cd 1
172.16.20.1 172.16.20.1 32 0x80000003 0x006e8f 2
Net Link States (Area 0)
Link ID ADV Router Age Seq# Checksum
172.16.10.1 172.16.10.1 145 0x80000001 0x00953d
the 20.2 interface on this router has 2 ospf links.
The left-facing out to RA, a crossover cable
The right-facing out to RC, a serial cable.
If the solution I found is correct, why is this serial link not being counted twice? The solution (I think)
is revealed after the configuration of the next router...
LabC - No OSPF at D yet
show ip ospf database
OSPF Router with ID (172.16.40.1) (Process ID 102)
Router Link States (Area 0)
Link ID ADV Router Age Seq# Checksum Link count
172.16.10.1 172.16.10.1 542 0x80000002 0x0067cd 1
172.16.20.1 172.16.20.1 90 0x80000004 0x00a551 3
172.16.40.1 172.16.40.1 37 0x80000004 0x00e47c 4
Net Link States (Area 0)
Link ID ADV Router Age Seq# Checksum
172.16.10.1 172.16.10.1 542 0x80000001 0x00953d
NOW we can see that the 20.1 link, which is the right-facing interface on LabB.. aka the router ID..
has THREE OSPF links.
Nothing changed on the left side of B. But on the right side, we now have an active OSPF router at the
other end of the link. This leads me to believe that the forum post was correct that 'serial links are counted twice',
but, more specifically, BOTH ENDS of the serial(PPP) link are counted... IF there is an OSPF router on each end.
This is backed up by the fact that LabC, OSPF id 40.1, has four OSPF links. The top-facing link to the 30
network DOES count.. even though it has no OSPF router on the other end. It counts because it's not a serial link.
The requirement of having an OSPF router on the other end for an interface to count here, only applies
to serial links. And pertains to BOTH ends of the link being counted.
In LabC's case, we have one serial at left, being counted twice. One ethernet at top, being counted once. And
one serial at right only being counted once because LabD is not active with OSPF yet.
If this is correct, then we should see Lab C's 40.1 count go to 5 after LabD is set for OSPF....
LabD - all 4 routers have OSPF
show ip ospf database
OSPF Router with ID (172.16.50.1) (Process ID 103)
Router Link States (Area 0)
Link ID ADV Router Age Seq# Checksum Link count
172.16.10.1 172.16.10.1 785 0x80000002 0x0067cd 1
172.16.20.1 172.16.20.1 333 0x80000004 0x00a551 3
172.16.40.1 172.16.40.1 111 0x80000005 0x00013b 5
172.16.50.1 172.16.50.1 53 0x80000003 0x001023 3
Net Link States (Area 0)
Link ID ADV Router Age Seq# Checksum
172.16.10.1 172.16.10.1 785 0x80000001 0x00953d
and back to LabC.....
show ip ospf database
OSPF Router with ID (172.16.40.1) (Process ID 102)
Router Link States (Area 0)
Link ID ADV Router Age Seq# Checksum Link count
172.16.10.1 172.16.10.1 1174 0x80000002 0x0067cd 1
172.16.20.1 172.16.20.1 722 0x80000004 0x00a551 3
172.16.40.1 172.16.40.1 500 0x80000005 0x00013b 5
172.16.50.1 172.16.50.1 441 0x80000003 0x001023 3
Net Link States (Area 0)
Link ID ADV Router Age Seq# Checksum
172.16.10.1 172.16.10.1 1174 0x80000001 0x00953d
Looks good! The link count for each router makes sense if you count the serial interfaces twice (one for each end).
the OSPF databases now match across all 4 routers.
NOTE that this is a database of routers, identified by
router ID. It is not a topology that lists routers AND routes, like in
the "equivalent" eigrp command show eigrp topology
Note that the .30 network is NOT represented here.
LabA#
show ip ospf database
OSPF Router with ID (172.16.10.1) (Process ID 100)
Router Link States (Area 0)
Link ID ADV Router Age Seq# Checksum Link count
172.16.10.1 172.16.10.1 1138 0x80000002 0x0067cd 1
172.16.20.1 172.16.20.1 686 0x80000004 0x00a551 3
172.16.40.1 172.16.40.1 463 0x80000005 0x00013b 5
172.16.50.1 172.16.50.1 404 0x80000003 0x001023 3
Net Link States (Area 0)
Link ID ADV Router Age Seq# Checksum
172.16.10.1 172.16.10.1 1138 0x80000001 0x00953d
LabB#
show ip ospf database
OSPF Router with ID (172.16.20.1) (Process ID 101)
Router Link States (Area 0)
Link ID ADV Router Age Seq# Checksum Link count
172.16.10.1 172.16.10.1 1151 0x80000002 0x0067cd 1
172.16.20.1 172.16.20.1 699 0x80000004 0x00a551 3
172.16.40.1 172.16.40.1 476 0x80000005 0x00013b 5
172.16.50.1 172.16.50.1 417 0x80000003 0x001023 3
Net Link States (Area 0)
Link ID ADV Router Age Seq# Checksum
172.16.10.1 172.16.10.1 1151 0x80000001 0x00953d
LabC#
show ip ospf database
OSPF Router with ID (172.16.40.1) (Process ID 102)
Router Link States (Area 0)
Link ID ADV Router Age Seq# Checksum Link count
172.16.10.1 172.16.10.1 1174 0x80000002 0x0067cd 1
172.16.20.1 172.16.20.1 722 0x80000004 0x00a551 3
172.16.40.1 172.16.40.1 500 0x80000005 0x00013b 5
172.16.50.1 172.16.50.1 441 0x80000003 0x001023 3
Net Link States (Area 0)
Link ID ADV Router Age Seq# Checksum
172.16.10.1 172.16.10.1 1174 0x80000001 0x00953d
LabD#
show ip ospf database
OSPF Router with ID (172.16.50.1) (Process ID 103)
Router Link States (Area 0)
Link ID ADV Router Age Seq# Checksum Link count
172.16.10.1 172.16.10.1 785 0x80000002 0x0067cd 1
172.16.20.1 172.16.20.1 333 0x80000004 0x00a551 3
172.16.40.1 172.16.40.1 111 0x80000005 0x00013b 5
172.16.50.1 172.16.50.1 53 0x80000003 0x001023 3
Net Link States (Area 0)
Link ID ADV Router Age Seq# Checksum
172.16.10.1 172.16.10.1 785 0x80000001 0x00953d
Below is our routing tables with OSPF data. We do see the .30 network here.
Everyone can reach it:
LabA via LabB's 10.2
LabB via LabC's 20.2
LabC via direct connection
LabD via LabC's 40.1
LabA#
show ip route
172.16.0.0/16 is variably subnetted, 6 subnets, 2 masks
C 172.16.10.0/24 is directly connected, FastEthernet0/0
L 172.16.10.1/32 is directly connected, FastEthernet0/0
O 172.16.20.0/24 [110/65] via 172.16.10.2, 00:28:03, FastEthernet0/0
O 172.16.30.0/24 [110/66] via 172.16.10.2, 00:21:35, FastEthernet0/0
O 172.16.40.0/24 [110/129] via 172.16.10.2, 00:21:25, FastEthernet0/0
O 172.16.50.0/24 [110/130] via 172.16.10.2, 00:17:40, FastEthernet0/0
LabB#
show ip route
172.16.0.0/16 is variably subnetted, 7 subnets, 2 masks
C 172.16.10.0/24 is directly connected, FastEthernet0/0
L 172.16.10.2/32 is directly connected, FastEthernet0/0
C 172.16.20.0/24 is directly connected, Serial0/0/0
L 172.16.20.1/32 is directly connected, Serial0/0/0
O 172.16.30.0/24 [110/65] via 172.16.20.2, 00:27:04, Serial0/0/0
O 172.16.40.0/24 [110/128] via 172.16.20.2, 00:26:54, Serial0/0/0
O 172.16.50.0/24 [110/129] via 172.16.20.2, 00:23:09, Serial0/0/0
LabC#
show ip route
172.16.0.0/16 is variably subnetted, 8 subnets, 2 masks
O 172.16.10.0/24 [110/65] via 172.16.20.1, 00:27:52, Serial0/0/0
C 172.16.20.0/24 is directly connected, Serial0/0/0
L 172.16.20.2/32 is directly connected, Serial0/0/0
C 172.16.30.0/24 is directly connected, FastEthernet0/0
L 172.16.30.1/32 is directly connected, FastEthernet0/0
C 172.16.40.0/24 is directly connected, Serial0/0/1
L 172.16.40.1/32 is directly connected, Serial0/0/1
O 172.16.50.0/24 [110/65] via 172.16.40.2, 00:23:36, Serial0/0/1
LabD#
show ip route
172.16.0.0/16 is variably subnetted, 7 subnets, 2 masks
O 172.16.10.0/24 [110/129] via 172.16.40.1, 00:25:20, Serial0/0/0
O 172.16.20.0/24 [110/128] via 172.16.40.1, 00:25:20, Serial0/0/0
O 172.16.30.0/24 [110/65] via 172.16.40.1, 00:25:20, Serial0/0/0
C 172.16.40.0/24 is directly connected, Serial0/0/0
L 172.16.40.2/32 is directly connected, Serial0/0/0
C 172.16.50.0/24 is directly connected, FastEthernet0/0
L 172.16.50.1/32 is directly connected, FastEthernet0/0
moving on.......
9.5 - OSPF DR and BDR Elections
EachRouter(config)#
hostname X (A, B, or C)
EachRouter(config)#
line con 0
EachRouter(config-line)#
exec-timeout 0 0
A(config)#
int f0/0
A(config-if)#
ip addr 10.1.1.1 255.255.255.0
A(config-if)#
no shut
A(config)#
router ospf 12345
A(config-router)#
net 10.1.1.0 0.0.0.255 area 0
00:23:30: %OSPF-5-ADJCHG: Process 12345, Nbr 10.1.1.3 on FastEthernet0/0 from LOADING to FULL, Loading Done
00:23:30: %OSPF-5-ADJCHG: Process 12345, Nbr 10.1.1.2 on FastEthernet0/0 from LOADING to FULL, Loading Done
A#
show ip ospf int
note this output was generated AFTER all 3 routers set for OSPF
FastEthernet0/0 is up, line protocol is up
Internet address is 10.1.1.1/24, Area 0
Process ID 12345, Router ID 10.1.1.1, Network Type BROADCAST, Cost: 1
Transmit Delay is 1 sec, State DROTHER, Priority 1
Designated Router (ID) 10.1.1.3, Interface address 10.1.1.3
Backup Designated Router (ID) 10.1.1.2, Interface address 10.1.1.2
Timer intervals configured, Hello 10, Dead 40, Wait 40, Retransmit 5
Hello due in 00:00:04
Index 1/1, flood queue length 0
Next 0x0(0)/0x0(0)
Last flood scan length is 1, maximum is 1
Last flood scan time is 0 msec, maximum is 0 msec
Neighbor Count is 2, Adjacent neighbor count is 2
Adjacent with neighbor 10.1.1.3 (Designated Router)
Adjacent with neighbor 10.1.1.2 (Backup Designated Router)
Suppress hello for 0 neighbor(s)
A(config-if)#shut
A(config-if)#
%LINK-5-CHANGED: Interface FastEthernet0/0, changed state to administratively down
%LINEPROTO-5-UPDOWN: Line protocol on Interface FastEthernet0/0, changed state to down
00:40:28: %OSPF-5-ADJCHG: Process 12345, Nbr 10.1.1.2 on FastEthernet0/0 from FULL to DOWN, Neighbor Down: Interface down or detached
00:40:28: OSPF: Build router LSA for area 0, router ID 10.1.1.1, seq 0xffffffff80000003
00:40:28: %OSPF-5-ADJCHG: Process 12345, Nbr 10.1.1.3 on FastEthernet0/0 from FULL to DOWN, Neighbor Down: Interface down or detached
00:40:28: OSPF: Build router LSA for area 0, router ID 10.1.1.1, seq 0xffffffff80000004
00:40:28: OSPF: Build router LSA for area 0, router ID 10.1.1.1, seq 0xffffffff80000004
A(config-if)#no shut
A(config-if)#
%LINK-5-CHANGED: Interface FastEthernet0/0, changed state to up
%LINEPROTO-5-UPDOWN: Line protocol on Interface FastEthernet0/0, changed state to up
00:40:48: OSPF: Build router LSA for area 0, router ID 10.1.1.1, seq 0xffffffff80000004
00:41:27: OSPF: Backup seen Event before WAIT timer on FastEthernet0/0
00:41:27: OSPF: DR/BDR election on FastEthernet0/0
00:41:27: OSPF: Elect BDR 10.1.1.2
00:41:27: OSPF: Elect DR 10.1.1.3
00:41:27: DR: 10.1.1.3 (Id) BDR: 10.1.1.2 (Id)
00:41:27: OSPF: Send DBD to 10.1.1.3 on FastEthernet0/0 seq 0x5accb8e2 opt 0x00 flag 0x7 len 32
B(config)#
int f0/0
B(config-if)#
ip addr 10.1.1.2 255.255.255.0
B(config-if)#
no shut
B(config)#
router ospf 12345
B(config-router)#
net 10.1.1.0 0.0.0.255 area 0
00:23:29: %OSPF-5-ADJCHG: Process 12345, Nbr 10.1.1.3 on FastEthernet0/0 from LOADING to FULL, Loading Done
00:23:29: %OSPF-5-ADJCHG: Process 12345, Nbr 10.1.1.1 on FastEthernet0/0 from LOADING to FULL, Loading Done
B#
show ip ospf int
note this output was generated AFTER all 3 routers set for OSPF
FastEthernet0/0 is up, line protocol is up
Internet address is 10.1.1.2/24, Area 0
Process ID 12345, Router ID 10.1.1.2, Network Type BROADCAST, Cost: 1
Transmit Delay is 1 sec, State BDR, Priority 1
Designated Router (ID) 10.1.1.3, Interface address 10.1.1.3
Backup Designated Router (ID) 10.1.1.2, Interface address 10.1.1.2
Timer intervals configured, Hello 10, Dead 40, Wait 40, Retransmit 5
Hello due in 00:00:05
Index 1/1, flood queue length 0
Next 0x0(0)/0x0(0)
Last flood scan length is 1, maximum is 1
Last flood scan time is 0 msec, maximum is 0 msec
Neighbor Count is 2, Adjacent neighbor count is 2
Adjacent with neighbor 10.1.1.1
Adjacent with neighbor 10.1.1.3 (Designated Router)
Suppress hello for 0 neighbor(s)
B#debug ip ospf adj
OSPF adjacency events debugging is on
B#
00:39:21: OSPF: DR/BDR election on FastEthernet0/0
00:39:21: OSPF: Elect BDR 10.1.1.2
00:39:21: OSPF: Elect DR 10.1.1.3
00:39:21: DR: 10.1.1.3 (Id) BDR: 10.1.1.2 (Id)
00:41:01: %OSPF-5-ADJCHG: Process 12345, Nbr 10.1.1.1 on FastEthernet0/0 from FULL to DOWN, Neighbor Down: Dead timer expired
00:41:01: %OSPF-5-ADJCHG: Process 12345, Nbr 10.1.1.1 on FastEthernet0/0 from FULL to DOWN, Neighbor Down: Interface down or detached
00:41:01: OSPF: Build router LSA for area 0, router ID 10.1.1.2, seq 0xffffffff80000003
00:41:01: OSPF: DR/BDR election on FastEthernet0/0
00:41:01: OSPF: Elect BDR 10.1.1.2
00:41:01: OSPF: Elect DR 10.1.1.3
C(config)#
int f0/0
C(config-if)#
ip addr 10.1.1.3 255.255.255.0
C(config-if)#
no shut
C(config)#
router ospf 12345
C(config-router)#
net 10.1.1.0 0.0.0.255 area 0
00:23:27: %OSPF-5-ADJCHG: Process 12345, Nbr 10.1.1.1 on FastEthernet0/0 from LOADING to FULL, Loading Done
00:23:27: %OSPF-5-ADJCHG: Process 12345, Nbr 10.1.1.2 on FastEthernet0/0 from LOADING to FULL, Loading Done
C#
show ip ospf int
note this output was generated AFTER all 3 routers set for OSPF
FastEthernet0/0 is up, line protocol is up
Internet address is 10.1.1.3/24, Area 0
Process ID 12345, Router ID 10.1.1.3, Network Type BROADCAST, Cost: 1
Transmit Delay is 1 sec, State DR, Priority 1
Designated Router (ID) 10.1.1.3, Interface address 10.1.1.3
Backup Designated Router (ID) 10.1.1.2, Interface address 10.1.1.2
Timer intervals configured, Hello 10, Dead 40, Wait 40, Retransmit 5
Hello due in 00:00:00
Index 1/1, flood queue length 0
Next 0x0(0)/0x0(0)
Last flood scan length is 1, maximum is 1
Last flood scan time is 0 msec, maximum is 0 msec
Neighbor Count is 2, Adjacent neighbor count is 2
Adjacent with neighbor 10.1.1.1
Adjacent with neighbor 10.1.1.2 (Backup Designated Router)
Suppress hello for 0 neighbor(s)
C#debug ip ospf adj
OSPF adjacency events debugging is on
C#
00:39:19: OSPF: DR/BDR election on FastEthernet0/0
00:39:19: OSPF: Elect BDR 10.1.1.2
00:39:19: OSPF: Elect DR 10.1.1.3
00:39:19: DR: 10.1.1.3 (Id) BDR: 10.1.1.2 (Id)
00:40:59: %OSPF-5-ADJCHG: Process 12345, Nbr 10.1.1.1 on FastEthernet0/0 from FULL to DOWN, Neighbor Down: Dead timer expired
00:40:59: %OSPF-5-ADJCHG: Process 12345, Nbr 10.1.1.1 on FastEthernet0/0 from FULL to DOWN, Neighbor Down: Interface down or detached
00:40:59: OSPF: Build router LSA for area 0, router ID 10.1.1.3, seq 0xffffffff80000003
00:40:59: OSPF: Build net LSA for area 0, router ID 10.1.1.3, seq 0xffffffff80000003
00:40:59: OSPF: DR/BDR election on FastEthernet0/0
00:40:59: OSPF: Elect BDR 10.1.1.2
00:40:59: OSPF: Elect DR 10.1.1.3
DR and BDR automtically set based on higest IP address
Note our network type is BROADCAST because we're using ethernet interfaces...
it would be point-to-point if using a serial connection
we want to manually overide the priority of the router. ZERO priority means it wont participate in the election process
MAX priority of 255 means no other router can beat it for DR
We'll set the priority for router A to 3.
It will beome the DR only after we shut/no shut the interface router
AND
manually power on/off the other two routers
A(config)#
int f0/0
A(config-int)#
ip ospf priority 3
A(config-int)#
shut
A(config-int)#
no shut
A#
debug ip ospf adj
B#
debug ip ospf adj
00:05:50: OSPF: DR/BDR election on FastEthernet0/0
00:05:50: OSPF: Elect BDR 10.1.1.2
00:05:50: OSPF: Elect DR 10.1.1.1
00:05:50: OSPF: Elect BDR 10.1.1.2
00:05:50: OSPF: Elect DR 10.1.1.1
00:05:50: DR: 10.1.1.1 (Id) BDR: 10.1.1.2 (Id)
00:05:50: OSPF: Send DBD to 10.1.1.1 on FastEthernet0/0 seq 0x10164ebb opt 0x00 flag 0x7 len 32
00:05:50: OSPF: Build router LSA for area 0, router ID 10.1.1.2, seq 0xffffffff80000002
00:05:52: OSPF: Rcv DBD from 10.1.1.1 on FastEthernet0/0 seq 0x20368093 opt 0x00 flag 0x7 len 32 mtu 1500 state EXSTART
00:05:52: OSPF: First DBD and we are not SLAVE
00:05:55: OSPF: Send DBD to 10.1.1.1 on FastEthernet0/0 seq 0x10164ebb opt 0x00 flag 0x7 len 32
00:05:55: OSPF: Rcv DBD from 10.1.1.1 on FastEthernet0/0 seq 0x10164ebb opt 0x00 flag 0x2 len 112 mtu 1500 state EXSTART
00:05:55: OSPF: NBR Negotiation Done. We are the MASTER
00:05:55: OSPF: Send DBD to 10.1.1.1 on FastEthernet0/0 seq 0x10164ebc opt 0x00 flag 0x3 len 52
00:05:55: OSPF: Rcv DBD from 10.1.1.1 on FastEthernet0/0 seq 0x10164ebc opt 0x00 flag 0x0 len 32 mtu 1500 state EXCHANGE
00:05:55: OSPF: Send DBD to 10.1.1.1 on FastEthernet0/0 seq 0x10164ebd opt 0x00 flag 0x1 len 32
00:05:55: OSPF: Rcv DBD from 10.1.1.1 on FastEthernet0/0 seq 0x10164ebd opt 0x00 flag 0x0 len 32 mtu 1500 state EXCHANGE
00:05:55: Exchange Done with 10.1.1.1 on FastEthernet0/0
00:05:55: OSPF: Database request to 10.1.1.1
00:05:55: OSPF: sent LS REQ packet to 10.1.1.1, length 36
00:05:55: OSPF: Rcv DBD from 10.1.1.1 on FastEthernet0/0 seq 0x10164ebd opt 0x00 flag 0x0 len 32 mtu 1500 state LOADING
00:05:55: Synchronized with with 10.1.1.1 on FastEthernet0/0, state FULL
00:05:55: %OSPF-5-ADJCHG: Process 12345, Nbr 10.1.1.1 on FastEthernet0/0 from LOADING to FULL, Loading Done
00:05:55: OSPF: Build router LSA for area 0, router ID 10.1.1.2, seq 0xffffffff80000002
C#
debug ip ospf adj
00:06:13: OSPF: DR/BDR election on FastEthernet0/0
00:06:13: OSPF: Elect BDR 10.1.1.2
00:06:13: OSPF: Elect DR 10.1.1.1
00:06:13: DR: 10.1.1.1 (Id) BDR: 10.1.1.2 (Id)
00:06:13: OSPF: Send DBD to 10.1.1.1 on FastEthernet0/0 seq 0x1cc5536d opt 0x00 flag 0x7 len 32
00:06:13: OSPF: Send DBD to 10.1.1.2 on FastEthernet0/0 seq 0x3d51ca66 opt 0x00 flag 0x7 len 32
00:06:13: OSPF: Build router LSA for area 0, router ID 10.1.1.3, seq 0xffffffff80000002
00:06:17: OSPF: Rcv DBD from 10.1.1.1 on FastEthernet0/0 seq 0x6b532eec opt 0x00 flag 0x7 len 32 mtu 1500 state EXSTART
00:06:17: OSPF: First DBD and we are not SLAVE
00:06:17: OSPF: Rcv DBD from 10.1.1.2 on FastEthernet0/0 seq 0x783110f4 opt 0x00 flag 0x7 len 32 mtu 1500 state EXSTART
00:06:17: OSPF: First DBD and we are not SLAVE
00:06:18: OSPF: Send DBD to 10.1.1.2 on FastEthernet0/0 seq 0x3d51ca66 opt 0x00 flag 0x7 len 32
00:06:18: OSPF: Send DBD to 10.1.1.1 on FastEthernet0/0 seq 0x1cc5536d opt 0x00 flag 0x7 len 32
00:06:18: OSPF: Rcv DBD from 10.1.1.2 on FastEthernet0/0 seq 0x3d51ca66 opt 0x00 flag 0x2 len 132 mtu 1500 state EXSTART
00:06:18: OSPF: NBR Negotiation Done. We are the MASTER
00:06:18: OSPF: Send DBD to 10.1.1.2 on FastEthernet0/0 seq 0x3d51ca67 opt 0x00 flag 0x3 len 52
00:06:18: OSPF: Rcv DBD from 10.1.1.1 on FastEthernet0/0 seq 0x1cc5536d opt 0x00 flag 0x2 len 132 mtu 1500 state EXSTART
00:06:18: OSPF: NBR Negotiation Done. We are the MASTER
00:06:18: OSPF: Send DBD to 10.1.1.1 on FastEthernet0/0 seq 0x1cc5536e opt 0x00 flag 0x3 len 52
00:06:18: OSPF: Rcv DBD from 10.1.1.2 on FastEthernet0/0 seq 0x3d51ca67 opt 0x00 flag 0x0 len 32 mtu 1500 state EXCHANGE
00:06:18: OSPF: Send DBD to 10.1.1.2 on FastEthernet0/0 seq 0x3d51ca68 opt 0x00 flag 0x1 len 32
00:06:18: OSPF: Rcv DBD from 10.1.1.1 on FastEthernet0/0 seq 0x1cc5536e opt 0x00 flag 0x0 len 32 mtu 1500 state EXCHANGE
00:06:18: OSPF: Send DBD to 10.1.1.1 on FastEthernet0/0 seq 0x1cc5536f opt 0x00 flag 0x1 len 32
00:06:18: OSPF: Rcv DBD from 10.1.1.2 on FastEthernet0/0 seq 0x3d51ca68 opt 0x00 flag 0x0 len 32 mtu 1500 state EXCHANGE
00:06:18: Exchange Done with 10.1.1.2 on FastEthernet0/0
00:06:18: OSPF: Database request to 10.1.1.2
00:06:18: OSPF: sent LS REQ packet to 10.1.1.2, length 48
00:06:18: OSPF: Rcv DBD from 10.1.1.1 on FastEthernet0/0 seq 0x1cc5536f opt 0x00 flag 0x0 len 32 mtu 1500 state EXCHANGE
verify on all three routers
A#
show ip ospf interface f0/0
FastEthernet0/0 is up, line protocol is up
Internet address is 10.1.1.1/24, Area 0
Process ID 12345, Router ID 10.1.1.1, Network Type BROADCAST, Cost: 1
Transmit Delay is 1 sec, State DR, Priority 3
Designated Router (ID) 10.1.1.1, Interface address 10.1.1.1
Backup Designated Router (ID) 10.1.1.2, Interface address 10.1.1.2
Timer intervals configured, Hello 10, Dead 40, Wait 40, Retransmit 5
Hello due in 00:00:09
Index 1/1, flood queue length 0
Next 0x0(0)/0x0(0)
Last flood scan length is 1, maximum is 1
Last flood scan time is 0 msec, maximum is 0 msec
Neighbor Count is 2, Adjacent neighbor count is 2
Adjacent with neighbor 10.1.1.2 (Backup Designated Router)
Adjacent with neighbor 10.1.1.3
Suppress hello for 0 neighbor(s)
A#
show ip ospf neighbor
Neighbor ID Pri State Dead Time Address Interface
10.1.1.2 1 FULL/BDR 00:00:37 10.1.1.2 FastEthernet0/0
10.1.1.3 1 FULL/DROTHER 00:00:30 10.1.1.3 FastEthernet0/0
B#
show ip ospf interface f0/0
FastEthernet0/0 is up, line protocol is up
Internet address is 10.1.1.2/24, Area 0
Process ID 12345, Router ID 10.1.1.2, Network Type BROADCAST, Cost: 1
Transmit Delay is 1 sec, State BDR, Priority 1
Designated Router (ID) 10.1.1.1, Interface address 10.1.1.1
Backup Designated Router (ID) 10.1.1.2, Interface address 10.1.1.2
Timer intervals configured, Hello 10, Dead 40, Wait 40, Retransmit 5
Hello due in 00:00:08
Index 1/1, flood queue length 0
Next 0x0(0)/0x0(0)
Last flood scan length is 1, maximum is 1
Last flood scan time is 0 msec, maximum is 0 msec
Neighbor Count is 2, Adjacent neighbor count is 2
Adjacent with neighbor 10.1.1.1 (Designated Router)
Adjacent with neighbor 10.1.1.3
Suppress hello for 0 neighbor(s)
B#
show ip ospf neighbor
Neighbor ID Pri State Dead Time Address Interface
10.1.1.1 3 FULL/DR 00:00:35 10.1.1.1 FastEthernet0/0
10.1.1.3 1 FULL/DROTHER 00:00:31 10.1.1.3 FastEthernet0/0
C#
show ip ospf interface f0/0
FastEthernet0/0 is up, line protocol is up
Internet address is 10.1.1.3/24, Area 0
Process ID 12345, Router ID 10.1.1.3, Network Type BROADCAST, Cost: 1
Transmit Delay is 1 sec, State DROTHER, Priority 1
Designated Router (ID) 10.1.1.1, Interface address 10.1.1.1
Backup Designated Router (ID) 10.1.1.2, Interface address 10.1.1.2
Timer intervals configured, Hello 10, Dead 40, Wait 40, Retransmit 5
Hello due in 00:00:06
Index 1/1, flood queue length 0
Next 0x0(0)/0x0(0)
Last flood scan length is 1, maximum is 1
Last flood scan time is 0 msec, maximum is 0 msec
Neighbor Count is 2, Adjacent neighbor count is 2
Adjacent with neighbor 10.1.1.1 (Designated Router)
Adjacent with neighbor 10.1.1.2 (Backup Designated Router)
Suppress hello for 0 neighbor(s)
C#
show ip ospf neighbor/span>
Neighbor ID Pri State Dead Time Address Interface
10.1.1.1 3 FULL/DR 00:00:35 10.1.1.1 FastEthernet0/0
10.1.1.2 1 FULL/BDR 00:00:37 10.1.1.2 FastEthernet0/0
Router1 is the DR with priority 3
still need more work to understand the output of the defbu ospf adj
Chapter 9 Review Questions
1. There are three possible routes for a router to reach a destination network:
OSPF with a metric of 782
RIPv2 with a metric of 4
EIGRP with a composite metric of 20514560
Which route will be installed in the routing table?
EIGRP because it has the lowest Administrative Distance, and AD is always used before metric
ADs are:
ExternalEIGRP 170
RIP 120
OSPF 110
IGRP 100
EIGRP 90
Static 1
Connected 0
2. Which EIGRP information is held in RAM and maintained through the use of Hello and update packets?
Neighbor table
and
toplogy table
3. Describe the process identifier that is used to run OSPF on a router
The OSPF process id is only locally significant. A random number can be selected. But it's required in order to identify
a unique OSPF database instance. You can use the same, or a different number on each router, doesnt matter.
Any number can be used from 1 to 65,535. Process ID is supplied as an argument to the command router ospf
NOT to be confused with the area number which can be any number up to 4 billion. The area id identifies a logical grouping of routers.
area id is supplied as argument to the OSPF network id and mask command
Ex:
R1(config)#
router ospf 12345
R1(config-router)#
net 10.1.1.0 0.0.0.255 area 0
4. Where are EIGRP successor routes stored?
EIGRP succesor routers are stored in the routing table. The "succesor" is the successful or primary route.
The successor route is ALSO listed in the topology table,
The feasible successor is a BACKUP route and will ONLY be listed in the topology table, unless the successor route fails,
in which case the feasible successor would become the successor
Note that my EIGRP setup doesnt seem to folow this.
CTRL-F jump to "remotely connected via remote ingress ip address"
the book states that EIGRP is automatically load-balancing our two links from R1 to corp.. is this why there is no feasible successor here?
I did some research and found that in our case, we are not using a Feasible Successor. You CAN have two Successors with equal metric, in which case EIGRP will
automatically load-balance.
But I wanted to find out what a Feasible Successor actually looks like in the EIGRP topology table..
Kevin Wallace EIGRP article
Conclusion:
EIGRP topology table wouldnt specifically say "Feasible Successor", but you would know by two routes appearing, one with a lower metric.
In my topology we have two equal-metric links and they are both considered "Successors". EIGRP uses them equally (load-balanced)
Corp#
show ip eigrp toplogy
[cut]
P 172.16.10.0/24, 1 successors, FD is 28160
via 10.1.5.2 (28160/25600), FastEthernet0/0
P 192.168.10.0/24, 2 successors, FD is 2172416
via 10.1.3.2 (2172416/28160), Serial0/0/1
via 10.1.2.2 (2172416/28160), Serial0/0/0
P 192.168.20.0/24, 2 successors, FD is 2172416
via 10.1.3.2 (2172416/28160), Serial0/0/1
via 10.1.2.2 (2172416/28160), Serial0/0/0
P 192.168.30.0/24, 1 successors, FD is 2172416
via 10.1.4.2 (2172416/28160), Serial0/1/0
P 192.168.40.0/24, 1 successors, FD is 2172416
via 10.1.4.2 (2172416/28160), Serial0/1/0
5. Which command will display all the EIGRP feasible successor routes to a known router.
show ip eigrp topology
6. Find the configuration error. You type the following into your router, but dont see any routes in the routing table?
Router(config)#
router ospf 1
Router(config-router)#
network 10.0.0.0 255.0.0.0
wrong wildcard mask
instead, could have used
0.255.255.255
or
0.0.0.255
the point is we need to specify the first octet as "allowed" into our OSPF config with a 0 mask.
The remaining bits are 'dont care' bits aka 'wildcard' aka 255
7. Which three protocols support VLSM, summarization, and discontigous networking?
RIPv2
EIGRP
OSPF
all 3 build and mainting routing tables, provide classless routing which allows VLSM, summarization, and discontigous networks
RIPv1 and IGRP build/maintain routing tables, but dont offer classless routing
8. Which are true regarding OSPF areas?
the 'backbone' is area 0
if using other areas, they all must directly connect to area 0
9. Which two network types have a designated router and a backup designated router?
Broadcast
NBMA- Non broadcast multi access. Ex: Frame Relay
network types that DO NOT use DR/BDR:
point to point
broadcast multipoint
10. You need to configure a router with a distance-vector protocol that allows classless routing. Which to use?
EIGRP is considered 'advanced distance vector' (ripv2 wasnt an option)
11. You need the IP address of the devices with which the router has established an adjacency.
Also, the retransmit interval and the queue counts for the adjacent routers need to be checked. What command will display the required information?
show ip eigrp neighbors
WRONG: show ip eigrp adjacency - there is no such command.. the word 'adjacency' is only used with debug ip OSPF adjacency
here are the possible commands for show ip eigrp and debug ip eigrp
show ip eigrp ?
interfaces IP-EIGRP interfaces
neighbors IP-EIGRP neighbors
topology IP-EIGRP Topology Table
traffic IP-EIGRP Traffic Statistics
debug ip eigrp ?
summary IP-EIGRP summary route processing
12. You cant establish an adjacency relationship on a common ethernet link between two routers. Based on the output below, what is the cause of the problem?
RouterA#
Ethernet0/0 is up, line protocol is up
Internet Address 172.16.1.2/16, Area 0
Process ID 2, Router ID 172.126.1.2, Network Type BROADCAST, Cost: 10
Transmit Delay is 1 sec, State DR, Priority 1
Designated Router (ID) 172.16.1.2, interface address 172.16.1.1.
No backup designated router on this network
Timer intervals configured, Hello 5, Dead 20, Wait 20, Retransmit 5
Router B#
Internet Address 172.16.1.1/16, Area 0
Process ID 2, Router ID 172.126.1.1, Network Type BROADCAST, Cost: 10
Transmit Delay is 1 sec, State DR, Priority 1
Designated Router (ID) 172.16.1.1, interface address 172.16.1.2.
No backup designated router on this network
Timer intervals configured, Hello 10, Dead 40, Wait 40, Retransmit 5
mismatched timer intervals
OSPF default Hello is 10 and Dead is 40... RouterA was modified
13. Which is true regarding EIGRP successor routes?
Used in the routing table
also appears in the topolgy table
may (or may not) have a backup feasabile successor
14. Which type of OSPF network will elect a backup designated router?
broadcast multi-access
non-broadcast multiaccess
types of network that will NOT elect a BDR:
point to point and brodacast multipoint (hub/spoke topology)
15. Which two commands will place network 10.2.3.0/24 into area 0?
Router(config)#
router ospf 10
Router(config-router)#
network 10.2.3.0 0.0.0.255 area 0
16. With which network type will OSPF establish router adjacencies but not perform the DR/BDR election process?
Point to point
no election process occurs, there is never a DR on point to point
17. What are three reasons for creating OSPF in a heirarchical design?
decrease routing overhead
speed up convergence
confine stability to single areas of the network
18. What is the administrative distance of OSPF?
110
19.
no auto summary
the network is considered discontigous because we have two classful network subnetted (on the left and right),
seperated by a different classful address.
if auto summarization is taking place, the routers cant determine which side is which because both sides would be summarized as
Class B, 172.16.0.0, which isnt specific enough to distinguish between the sides.
20. IF routers in a single area are configured with the same priority value, what value does a router use for the OSPF router ID in the absence of a loopback interface?
The highest IP of any PHSYICAL interface.
Trick question. Highest IP of any LOGICAL interface is an option. And is correct IF you had logical interfaces, but the question
states that any "logical interfaces are absent".
At OSPF startup, the highest IP of *any* active interface on the router becomes the OSPF router ID. If you have loopback (logical) interfaces configured,
one of them (the largest IP) will *override* the phsyical interfaces and the loopback IP becomes the RID.
Reference for which loopback (if multiple) wins:
packetpushers.net
------------------------------------------------------------------------------
END CHAPTER 9
41 hours 2-14 thru 2-28-22
original total 184 hours
14 hours review 12-26 thru 12-28-22
review total hours 46
book page 502/822
184 + 46 = 230 hours * 60 = (13,800 min) / 500 pages =
avg 28 min/page (includes reading and exercises/labs + online research)
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enable telnet on R2 and set password
R2(config)# line vty 0 15
R2(config-line)# password telnet
R2(config-line)# login
enable telnet on R3 and set password
R3(config)# line vty 0 15
R3(config-line)# password telnet
R3(config-line)# login
R3# show run
--------------------------------------------------------------------------------
connect to R2 from R1
R1# telnet 193.1.1.2
prompt changes to R2 to indicate we are remoted in
R2>
exit the session ctrl + shift + 6, x
prompt changes back to R1
R1#
--------------------------------------------------------------------------------
connect to R3 from R1
R1# 193.1.1.3 note that the word 'telnet' is not required bc we are still in telnet mode
prompt changes to R3 to indicate we are remoted in
R3>
exit the session ctrl + shift + 6, x
prompt changes back to R1
R1#
--------------------------------------------------------------------------------
We have exited the sessions, but they are still open
R1# show sessions
R1# show users
... they must both be considered 'console' connections outbound and are not considered 'vty' until they are received inbound
the asterisk means something different here than above... doesnt mean default(most recent)session... what does it mean?
back to R2
R2# show users
back to R3
R3# show users
-------------------------------------------------------------------------------------
Important Considerations:
R2(config)# line vty 0 15
R2(config-line)# password telnet
R2(config-line)# login
enable telnet on R3 and set password
R3(config)# line vty 0 15
R3(config-line)# password telnet
R3(config-line)# login
note that the result of this command on each router, by default,
is to present all 15 lines in TWO SEPERATE chunks: 0-4 and 5-15
is to present all 15 lines in TWO SEPERATE chunks: 0-4 and 5-15
R3# show run
[cut]
!
!
!
line con 0
!
line aux 0
!
line vty 0 4
password telnet
login
line vty 5 15
password telnet
login
!
!
!
end
--------------------------------------------------------------------------------
connect to R2 from R1
R1# telnet 193.1.1.2
Trying 193.1.1..2 ...Open
User Access Verification
Password: telnet
prompt changes to R2 to indicate we are remoted in
R2>
exit the session ctrl + shift + 6, x
prompt changes back to R1
R1#
--------------------------------------------------------------------------------
connect to R3 from R1
R1# 193.1.1.3 note that the word 'telnet' is not required bc we are still in telnet mode
Trying 193.1.1..3 ...Open
User Access Verification
Password: telnet
prompt changes to R3 to indicate we are remoted in
R3>
exit the session ctrl + shift + 6, x
prompt changes back to R1
R1#
--------------------------------------------------------------------------------
We have exited the sessions, but they are still open
R1# show sessions
Conn Host Address Byte Idle Conn Name
1 193.1.1.2 193.1.1.2 0 0 193.1.1.2
* 2 193.1.1.3 193.1.1.3 0 0 193.1.1.3
two telnet sessions- notice that the 'conn number' doesnt correspond to ip address in any way.
R1# show users
Line User Host(s) Idle Location
* 0 con 0 193.1.1.2 00:00:03
193.1.1.3 00:00:43
this is saying one user is on this router, with two outbound connections (but it isnt showing that they are vty connections)
... they must both be considered 'console' connections outbound and are not considered 'vty' until they are received inbound
the asterisk means something different here than above... doesnt mean default(most recent)session... what does it mean?
back to R2
R2# show users
Line User Host(s) Idle Location
* 4 vty 0 idle 00:00:00 193.1.1.1
Interface User Mode Idle Peer Address
this is saying that there is one (unnamed) user remoted in via line vty 4
back to R3
R3# show users
Line User Host(s) Idle Location
* 4 vty 0 idle 00:00:00 193.1.1.1
Interface User Mode Idle Peer Address
this is saying that there is one (unnamed) user remoted in via line vty 4
-------------------------------------------------------------------------------------
Important Considerations:
- asterisk indicates default session
- when telnetting in, you will be in user mode. If there is no password already set for PRIVILEGED MODE, you will be unable to enter
- be careful with 'exit'. it will exit the telnet session if you exit at priv. mode. Use 'disable' to leave priv mode.
-
after 'suspending' a session with ctrl+shift+6,x and youre back at your original priv. prompt, do not press enter to create line breaks-
rather than break lines as usual, the keystroke will cause this:
[Resuming connection 1 to 193.1.1.2 ... ]prompt will sit here until you strike enter again, then you'll return to that session. What is actually happening is that youre connecting to the 'default' telnet connection. The same behavior happens when youre at the 'show sessions' screen. Even if you are not viewing active sessions, the enter key(twice) will connect you to the default session
- you can use disconnect or exit to end a session
- Ex: disconnect 1 at the show sessions screen
We're going to build a host table on R1 so we can connect to the other routers via hostname rather than type in the IP address
the command is ip host name arg ip arg
R1(config)# ip host R2 193.1.1.2
R1(config)# ip host R3 193.1.1.3
Now if we enter R2 or telnet R2 we get the telnet prompt
R1# R2
same for the PING command
R1# ping R2
R1# show hosts
R1# telnet R2
R2> CTRL + SHIFT + 6, X
R1# telnet R3
R3> CTRL + SHIFT + 6, X
R1# show session
the command is ip host name arg ip arg
R1(config)# ip host R2 193.1.1.2
R1(config)# ip host R3 193.1.1.3
Now if we enter R2 or telnet R2 we get the telnet prompt
R1# R2
Trying 193.1.1.2 ...Open
User Access Verification
Password:
same for the PING command
R1# ping R2
Type escape sequence to abort.
Sending 5, 100-byte ICMP Echos to 193.1.1.2, timeout is 2 seconds:
!!!!!
Success rate is 100 percent (5/5), round-trip min/avg/max = 0/0/2 ms
R1# show hosts
Default Domain is not set
Name/address lookup uses domain service
Name servers are 255.255.255.255
Codes: UN - unknown, EX - expired, OK - OK, ?? - revalidate
temp - temporary, perm - permanent
NA - Not Applicable None - Not defined
Host Port Flags Age Type Address(es)
R2 None (perm, OK) 0 IP 193.1.1.2
R3 None (perm, OK) 0 IP 193.1.1.3
R1# telnet R2
R2> CTRL + SHIFT + 6, X
R1# telnet R3
R3> CTRL + SHIFT + 6, X
R1# show session
Conn Host Address Byte Idle Conn Name
1 R2 193.1.1.2 0 0 R2
* 2 R3 193.1.1.3 0 0 R3
Chapter 7 Review Questions
1. What does the command
confreg 0x2142
provide?
bypass startup-config, to allow password reset
2. Which command will copy the IOS to a backup host on your network?
copy flash tftp
3. You are troubleshooting a connectivity problem in your corporate network and want to isolate the problem. You suspect that a router on the route to an unreachable
network is at fault. What IOS user exec command should you issue?
traceroute
note this is not a priviliged mode command; it can be run from user mode
4. You copy a configuration from a network host to a router's RAM. The configuration looks correct, yet it is no working at all. What could the problem be?
when you perform a copy from a network host to a router, the interfaces are automatically shut down and have to be manually enabled with no shutdown
5. A network administrator wants to upgrade the IOS of a router without removing the image currently installed. What command will display the amount of memory consumed by the
current IOS image and indicate whether there is enough room available to hold both the current and new images?
show flash
6. The corporate office sends you a new router to connect, but upon connecting the console cable, you see that there is already a configuration on the router.
What should be done before a new configuration is entered in the router?
erase NVRAM and restart the router
erase startup-config
reload
7. Which command loads a new version of the Cisco IOS into a router?
copy tftp flash
8. Which command will show you the IOS version running on your router?
show version
9. What should the configuration register value be after you successfully complete the password recovery procedure and return the router to normal operation?
0x2102
10. You save the configuration on a router with the
copy running-config startup-config
command and reboot the router. The router, however, comes up with a blank configuration. What can the problem be?
wrong config register causing you to bypass startup-confing in NVRAM
11. If you want to have more than one Telnet session open at the same time, what keystroke combination would you use?
CTRL+SHIFT+6, X
12. You are unsuccessful in telnetting into a remote device, but you could telnet to the router earlier, However, you can still ping the remote device.
What can the problem be?
access control list could be filtering telnet
OR
the VTY password may not be set on the target
13. What information is displayed by the
show hosts
command?
gives info on temporary DNS entries and permanent name-to-address mappings created using the ip host command
14. Name three commands that can be used to check LAN connectivity problems on a router?
trace
show interfaces
show ip route
15. You telnet to a router and make your necessary changes; now you want to end the Telnet session. What command do you type in?
exit
16. You telnet into a remote device and type
debug ip rip
but no output from the
debug
command is seen. What could the problem be?
to see console messages through a telnet session, you must enter the command terminal monitor
17. Which command displays the configuration register setting?
show version
18. You need to gather the IP address of a remote switch that is located in Hawaii. What can you do to find the address?
show cdp neighbors detail
19. You have your laptop directly connected into a router's Ethernet port. Which are requirements for the
copy flash tftp
command to be successful?
have a TFTP server running on the laptop
laptop must have an IP on the same subnet as the router interface
give the IP address of the laptop when asked after entering the command
20. The configuration register setting of 0x2102 provides what function to a router?
points to NVRAM for startup-configuration AND boot sequence
END CHAPTER 7
26 hours 1-19 thru 1-26-22
original total hours 89
7 hours review 12-23-22
review total hours 20.5
book page 344/822
avg 15 min/page (reading and exercises/labs)
Chapter 8 Exercises
pg 374
before I begin to configure this network, I want to look closer at the HARDWARE
Todd mentions these routers:
2811 with four serial interfaces and switch module or wireless card
1841
while the book was published in 2011, both routers appear to be available in 2021 packet tracer,
but both are considered legacy as of Feb 2022.
The 2811:
The 1841:
we're going to need to understand the MODULES. What are these?
a few examples:
NM-1E is a 1-port ethernet module
NM-1FE-TX is a fast ethernet module
NM-8A/s is an Eight Port Async/Sync Network Module
HWIC-2T is a 2-port serial WAN interface card
HWIC-AP-AG-B is a wireless card
What is an "NM module"?
A network module is a software module that implements a specific
function in a network stack, such as a data link interface, a transport protocol,
or a network application.
What is a "HWIC module"?
A high-speed WAN interface card
Here is a look inside a real 2811:
Back to the requirements for our lab- Todd says the 2811 'Corp' router needs a switch module
and four serial interfaces. NOTE the book doesnt give specifics on how to create the topology in Packet Tracer.
Our Packet Tracer 2811 offers these modules:
The NM-ESW-16 appears to be the only 'switch module', so I will add that.
And the HWIC-2T is a 2-Port Serial High-Speed WAN Interface Card, providing 2 serial ports.
I will add two of these.
next: R3, which needs to be a 2811 with a wirless card. I will add the HWIC-AP-AG-B:
The HWIC-AP-AG-B module is a High-Speed WAN Interface Card providing integrated Access Point
functionality in the Cisco 1800 (Modular), Cisco 2800,
and Cisco 3800 Integrated Services Routers.
It supports Single Band 802.11b/g or Dual Band 802.11a/b/g radios.
our router hardware is in place:
and here is where we need to end up
Next we need to figure out how to connect the server farm to the switch card on R1:
if I use the auto-select cable, I get a copper crossover cable connecting at fa0/0 on the router.
Per the diagram fa0/0 should
connect to R3. I need to connect the servers to the switch card on R1.
Instead of using the auto-select cable, I'll try a straight-through cable.
Success. While the auto-select cable did not give me an option as to what port it will connect to, I did get the option when
manually applying the straight-through cable. Instead of connecting to F0/0 which would require a crossover-cable(computer to router),
I will connect to the integrated switch at port F1/0, then connect the other two servers to F1/1 and F1/2, respectively.
Also worth noting: the Physical Device diagrams in Packet Tracer do not show cables plugged into the ports.
We are relying on the labels on the logical diagram to see which cables are plugged into which ports...
As far as how we can tell what is connected from within the CLI.. I dont know right now.
Now I will connect the other routers. Here is the chart specifiying what interfaces should be used:
Router
Network Address
Interface
Address
CORP
10.1.1.0
Vlan1 (switch card)
10.1.1.1
10.1.2.0
S0/0/0
10.1.2.1
10.1.3.0
S0/0/1 (DCE)
10.1.3.1
10.1.4.0
S0/1/0
10.1.4.1
10.1.5.0
F0/0
10.1.5.1
R1
10.1.2.0
S0/0/0 (DCE)
10.1.2.2
10.1.3.0
S0/0/1
10.1.3.2
192.168.10.0
F0/0
192.168.10.1
192.168.20.0
F0/1
192.168.20.1
R2
10.1.4.0
S0/0/0 (DCE)
10.1.4.2
192.168.30.0
F0/0
192.168.30.1
192.168.40.0
F0/0
192.168.40.1
R3
10.1.5.0
F0/0
10.1.5.2
172.16.10.0
Dot11Radio0/0/0
172.16.10.1
PROBLEM
The R1 router doesnt appear to have any serial interfaces
I will add an HWIC-2T card to both R1 and R2 since the diagram calls for serial interfaces.
The HWIC-2T is a Cisco 2-Port Serial High-Speed WAN Interface Card, providing 2 serial ports.
PROBLEM
The Corp router is not showing the expected available interfaces. I need to connect R1 to the S0/0/0 interface on Corp and R2 to the S0/0/1 interface on Corp.
My Corp router is not showing those interfaces:
Solution
the placement of the cards on the router determines which interface numbers will be available.
In this case, it seems the interfaces start from the bottom right corner and increase on each slot moving clockwise. I found this out by filling all four slots on my router
which led to all interfaces being available. I then ran a card in each slot individually to isolate which interface numbers correspond to each slot:
Interestingly, while the physical slots seem to follow a 'clockwise' pattern, the list of available slots in the logical diagram does not;
We get an output of interfaces corresponding to slot 2, then 3, 1, and 4. This is a 'bottom to top' then 'left to right' pattern. Tricky.
Having said all that... I will run cards in slots 1 and 2 for this lab since we only need interfaces S0/0/0, S0/0/1, S0/1/0
The Router topology:
I'm not clear on the connections from R1 and R2 to the clients.. I assume there are switches involved.
For now I will follow the next steps in the book which
are to configure the corp router as follows:
Router(config)#
hostname Corp
Corp(config)#
enable secret todd
Corp(config)#
interface vlan 1
Corp(config-if)#
description Switch Card to Core Network
Corp(config-if)#
ip address 10.1.1.1 255.255.255.0
Corp(config-if)#
no shut
----------------------------------------------------------------------------------------------------------------
Corp(config-if)#
int f1/0
Corp(config-if)#
description Switch Port connection to WWW Server
Corp(config-if)#
no shutdown
Corp(config-if)#
int f1/1
Corp(config-if)#
description Switch Port connection to Email Server
Corp(config-if)#
no shutdown
Corp(config-if)#
int f1/2
Corp(config-if)#
description Switch Port connection to DNS Server
Corp(config-if)#
no shutdown
----------------------------------------------------------------------------------------------------------------
Corp(config-if)#
int s0/0/0
Corp(config-if)#
description 1st Connection to R1
Corp(config-if)#
ip address 10.1.2.1 255.255.255.0
Corp(config-if)#
no shut
Corp(config-if)#
int s0/0/1
Corp(config-if)#
description 2nd Connection to R1
Corp(config-if)#
ip address 10.1.3.1 255.255.255.0
Corp(config-if)#
no shut
Corp(config-if)#
int s0/1/0
Corp(config-if)#
description Connection to R2
Corp(config-if)#
ip address 10.1.4.1 255.255.255.0
Corp(config-if)#
no shut
Corp(config-if)#
int fa0/0
Corp(config-if)#
description Connection to R3
Corp(config-if)#
ip address 10.1.5.1 255.255.255.0
Corp(config-if)#
no shut
----------------------------------------------------------------------------------------------------------------
Corp(config-if)#
line con 0
Corp(config-if)#
password console
Corp(config-if)#
login
Corp(config-if)#
logging synchro
Corp(config-if)#
exec-timeout 0 0
----------------------------------------------------------------------------------------------------------------
Corp(config-if)#
line aux 0
Corp(config-if)#
password aux
Corp(config-if)#
login
Corp(config-if)#
exit
----------------------------------------------------------------------------------------------------------------
Corp(config)#
line vty ?
<1-15>Last Line number
Corp(config)#
line vty 0 15
Corp(config-if)#
password telnet
Corp(config-if)#
login
Corp(config-if)#
exit
----------------------------------------------------------------------------------------------------------------
Corp(config)#
no ip domain lookup
Corp(config)#
banner motd # This is my Corp 2811 ISR Router #
Ctrl + Z
%SYS-5-CONFIG_I: Configured from console by console
(Ctrl-Z: When in a config mode, ends the config mode and returns you to privileged EXEC mode.... same as typing exit(?))
Corp#
copy run start
Destination filename [startup-config]?
Building configuration...
[OK]
----------------------------------------------------------------------------------------------------------------
Corp#
show ip int br
Interface IP-Address OK? Method Status Protocol
FastEthernet0/0 10.1.5.1 YES manual up down
FastEthernet0/1 unassigned YES unset administratively down down
Serial0/0/0 10.1.2.1 YES manual down down
Serial0/0/1 10.1.3.1 YES manual down down
Serial0/1/0 10.1.4.1 YES manual down down
Serial0/1/1 unassigned YES unset administratively down down
FastEthernet1/0 unassigned YES unset up up
FastEthernet1/1 unassigned YES unset up up
FastEthernet1/2 unassigned YES unset up up
FastEthernet1/3 unassigned YES unset administratively down down
FastEthernet1/4 unassigned YES unset administratively down down
FastEthernet1/5 unassigned YES unset administratively down down
FastEthernet1/6 unassigned YES unset administratively down down
FastEthernet1/7 unassigned YES unset administratively down down
FastEthernet1/8 unassigned YES unset administratively down down
FastEthernet1/9 unassigned YES unset administratively down down
FastEthernet1/10 unassigned YES unset administratively down down
FastEthernet1/11 unassigned YES unset administratively down down
FastEthernet1/12 unassigned YES unset administratively down down
FastEthernet1/13 unassigned YES unset administratively down down
FastEthernet1/14 unassigned YES unset administratively down down
FastEthernet1/15 unassigned YES unset administratively down down
Vlan1 10.1.1.1 YES manual up up
----------------------------------------------------------------------------------------------------------------
Corp#
show run
Building configuration...
Current configuration : 2073 bytes
!
version 15.1
no service timestamps log datetime msec
no service timestamps debug datetime msec
no service password-encryption
!
hostname Corp
!
!
!
enable secret 5 $1$mERr$V5ujdIM9bTB/I.ipB0gkJ0
!
!
!
!
!
!
no ip cef
no ipv6 cef
!
!
!
!
license udi pid CISCO2811/K9 sn FTX1017U440-
!
!
!
!
!
!
!
!
!
no ip domain-lookup
!
!
spanning-tree mode pvst
!
!
!
!
!
!
interface FastEthernet0/0
description connection to R3
ip address 10.1.5.1 255.255.255.0
duplex auto
speed auto
!
interface FastEthernet0/1
no ip address
duplex auto
speed auto
shutdown
!
interface Serial0/0/0
description 1st connection to R1
ip address 10.1.2.1 255.255.255.0
clock rate 2000000
!
interface Serial0/0/1
description 2nd connection to R1
ip address 10.1.3.1 255.255.255.0
clock rate 2000000
!
interface Serial0/1/0
description connection to R2
ip address 10.1.4.1 255.255.255.0
!
interface Serial0/1/1
no ip address
clock rate 2000000
shutdown
!
interface FastEthernet1/0
description switch port connection to WWW Server
!
interface FastEthernet1/1
description switch port connection to Email Server
!
interface FastEthernet1/2
description switch port connection to DNS Server
!
interface FastEthernet1/3
shutdown
!
interface FastEthernet1/4
shutdown
!
interface FastEthernet1/5
shutdown
!
interface FastEthernet1/6
shutdown
!
interface FastEthernet1/7
shutdown
!
interface FastEthernet1/8
shutdown
!
interface FastEthernet1/9
shutdown
!
interface FastEthernet1/10
shutdown
!
interface FastEthernet1/11
shutdown
!
interface FastEthernet1/12
shutdown
!
interface FastEthernet1/13
shutdown
!
interface FastEthernet1/14
shutdown
!
interface FastEthernet1/15
shutdown
!
interface Vlan1
description Switch Card to Core Network
ip address 10.1.1.1 255.255.255.0
!
ip classless
!
ip flow-export version 9
!
!
!
banner motd ^C This is my Corp 2811 ISR Router ^C
!
!
!
!
!
line con 0
exec-timeout 0 0
password console
logging synchronous
login
!
line aux 0
password aux
login
!
line vty 0 4
password telnet
login
line vty 5 15
password telnet
login
!
!
!
end
-----------------------------------------------------------------------------------------------------------------------
more configurations:
R1
Router(config)#
hostname R1
R1(config)#
enable secret todd
R1(config)#
int s0/0/0
R1(config-if)#
ip address 10.1.2.2 255.255.255.0
R1(config-if)#
Decription 1st connection to corp router
R1(config-if)#
no shut
-----------------------------------------------------------------------------------------------
R1(config-if)#
int s0/0/1
R1(config-if)#
ip address 10.1.3.2 255.255.255.0
R1(config-if)#
Decription 2nd connection to corp router
R1(config-if)#
no shut
-----------------------------------------------------------------------------------------------
R1(config-if)#
int f0/0
R1(config-if)#
ip address 192.168.10.1 255.255.255.0
R1(config-if)#
Decription connection to finance
R1(config-if)#
no shut
-----------------------------------------------------------------------------------------------
R1(config-if)#
int f0/1
R1(config-if)#
ip address 192.168.20.1 255.255.255.0
R1(config-if)#
Decription connection to marketing
R1(config-if)#
no shut
R1(config-if)#
exit
-----------------------------------------------------------------------------------------------
R1(config)#
line con 0
R1(config-line)#
password console
R1(config-line)#
login
R1(config-line)#
logging synchronous
R1(config-line)#
exec-timeout 0 0
-----------------------------------------------------------------------------------------------
R1(config-line)#
line aux 0
R1(config-line)#
password aux
R1(config-line)#
login
R1(config-line)#
exit
-----------------------------------------------------------------------------------------------
R1(config)#
line vty 0 ?
<0-15> Last Line number
R1(config)#
line vty 0 807
R1(config-line)#
password telnet
R1(config-line)#
login
R1(config-line)#
banner motd # This is my R1 Router #
R1(config-line)#
exit
-----------------------------------------------------------------------------------------------
R1(config)#
no ip domain-lookup
R1(config)#
exit
R1#
copy run start
R2
Router(config)#
hostname R2
R2(config)#
enable secret todd
R2(config)#
int s0/0/0
R2(config-if)#
ip address 10.1.4.2 255.255.255.0
R2(config-if)#
description connection to corp router
R2(config-if)#
no shut
-----------------------------------------------------------------------------------------------
R2(config-if)#
int f0/0
R2(config-if)#
ip address 192.168.30.1 255.255.255.0
R2(config-if)#
description connection to sales PC
R2(config-if)#
no shut
-----------------------------------------------------------------------------------------------
R2(config-if)#
int f0/1
R2(config-if)#
ip address 192.168.40.1 255.255.255.0
R2(config-if)#
description connection to HR pc
R2(config-if)#
no shut
-----------------------------------------------------------------------------------------------
R2(config-if)#
line con 0
R2(config-line)#
password console
R2(config-line)#
login
R2(config-line)#
logging synchronous
R2(config-line)#
exec-timeout 0 0
-----------------------------------------------------------------------------------------------
R2(config-line)#
line aux 0
R2(config-line)#
password aux
R2(config-line)#
login
R2(config-line)#
exit
-----------------------------------------------------------------------------------------------
R2(config)#
line vty 0 ?
<0-15> Last Line number
R2(config)#
line vty 0 807
R2(config-line)#
password telnet
R2(config-line)#
login
R2(config-line)#
banner motd # This is my R1 Router #
R2(config-line)#
exit
-----------------------------------------------------------------------------------------------
R2(config)#
no ip domain-lookup
R2(config)#
exit
R2#
copy run start
R3
Router(config)#
hostname R3
R3(config)#
enable secret todd
R3(config)#
int f0/0
R3(config-if)#
ip address 10.1.5.2 255.255.255.0
R3(config-if)#
description connection to corp router
R3(config-if)#
no shut
-----------------------------------------------------------------------------------------------
R3(config-if)#
int dot11radio0/0/0
R3(config-if)#
ip address 172.16.10.1 255.255.255.0
R3(config-if)#
description WLAN for mobile user
R3(config-if)#
no shut
R3(config-if)#
ssid ADMIN
stuck here 2-5-22-- packet tracer isnt taking me into the config-if-ssid prompt
R3(config-if-ssid)#
guest-mode
R3(config-if-ssid)#
authentication open
R3(config-if-ssid)#
ingrastructure-ssid
R3(config-if-ssid)#
exit
-----------------------------------------------------------------------------------------------
R3(config-if)#
line con 0
R3(config-line)#
password console
R3(config-line)#
login
R3(config-line)#
logging synchronous
R3(config-line)#
exec-timeout 0 0
-----------------------------------------------------------------------------------------------
R3(config-line)#
line aux 0
R3(config-line)#
password aux
R3(config-line)#
login
R3(config-line)#
exit
-----------------------------------------------------------------------------------------------
R3(config)#
line vty 0 ?
<0-15> Last Line number
R3(config)#
line vty 0 807
R3(config-line)#
password telnet
R3(config-line)#
login
R3(config-line)#
banner motd # This is my R1 Router #
R3(config-line)#
exit
-----------------------------------------------------------------------------------------------
R3(config)#
no ip domain-lookup
R3(config)#
exit
R3#
copy run start
PROBLEM
i cant get into conf-if-ssid prompt
R3(config-if)#
ssid ADMIN
%LINK-5-CHANGED: Interface Dot11Radio0/0/0, changed state to administratively down
%LINEPROTO-5-UPDOWN: Line protocol on Interface Dot11Radio0/0/0, changed state to down
%LINK-5-CHANGED: Interface Dot11Radio0/0/0, changed state to up
%LINEPROTO-5-UPDOWN: Line protocol on Interface Dot11Radio0/0/0, changed state to up
R3(config-if)#
research led me to this thread, which is a dead end:
further research led me here:
R3(config)# global config mode
R3(config)#
dot11 ssid ADMIN
creates an SSID or lets you config an existing SSID
R3(config-ssid)#
guest-mode
R3(config-ssid)#
%LINK-5-CHANGED: Interface Dot11Radio0/0/0, changed state to administratively down
%LINEPROTO-5-UPDOWN: Line protocol on Interface Dot11Radio0/0/0, changed state to down
%LINK-5-CHANGED: Interface Dot11Radio0/0/0, changed state to up
%LINEPROTO-5-UPDOWN: Line protocol on Interface Dot11Radio0/0/0, changed state to up
R3(config-ssid)#
authentication open
R3(config-ssid)#
%LINK-5-CHANGED: Interface Dot11Radio0/0/0, changed state to administratively down
%LINEPROTO-5-UPDOWN: Line protocol on Interface Dot11Radio0/0/0, changed state to down
%LINK-5-CHANGED: Interface Dot11Radio0/0/0, changed state to up
%LINEPROTO-5-UPDOWN: Line protocol on Interface Dot11Radio0/0/0, changed state to up
R3(config-ssid)#
infrastructure-ssid
R3(config-ssid)#infrastructure-ssid
^
% Invalid input detected at '^' marker.
this command given by the book doesnt appear to be valid
R3(config-ssid)#
?
authentication authentication method
exit Exit from ssid sub mode
guest-mode guest ssid
no Negate a command or set it's defaults
wpa-psk Configure Wi-Fi Protected Access pre-shared key
back into the interface to see what the options are
R3(config-ssid)#
int dot110/0/0
R3(config-if)#
?
arp Set arp type (arpa, probe, snap) or timeout or log options
bandwidth Set bandwidth informational parameter
cdp CDP interface subcommands
crypto Encryption/Decryption commands
delay Specify interface throughput delay
description Interface specific description
encryption Configure dot11 encryption parameters
exit Exit from interface configuration mode
fair-queue Enable Fair Queuing on an Interface
hold-queue Set hold queue depth
ip Interface Internet Protocol config commands
mac-address Manually set interface MAC address
mtu Set the interface Maximum Transmission Unit (MTU)
no Negate a command or set its defaults
priority-group Assign a priority group to an interface
service-policy Configure QoS Service Policy
shutdown Shutdown the selected interface
speed Set allowed radio bit rates
ssid Configure radio service set parameters
tx-ring-limit Configure PA level transmit ring limit
i'll consider the problem *mostly* solved. I was able to assign the SSD.
The infrastructure command may be expendable in this case... to be determined
here is our configuration for R3
R3#
show run
Building configuration...
Current configuration : 1682 bytes
!
version 15.1
no service timestamps log datetime msec
no service timestamps debug datetime msec
no service password-encryption
!
hostname R3
!
!
!
enable secret 5 $1$mERr$V5ujdIM9bTB/I.ipB0gkJ0
!
!
ip dhcp excluded-address 172.16.10.1 172.16.10.10
!
ip dhcp pool Admin
network 172.16.10.0 255.255.255.0
default-router 172.16.10.1
!
dot11 ssid ADMIN
authentication open
guest-mode
!
dot11 ssid ADMIN2
authentication open
guest-mode
!
!
!
ip cef
no ipv6 cef
!
!
!
!
license udi pid CISCO2811/K9 sn FTX1017RE40-
!
!
!
!
!
!
!
!
!
no ip domain-lookup
ip name-server 172.16.10.4
!
!
spanning-tree mode pvst
!
!
!
!
!
!
interface FastEthernet0/0
description connection to corp router
ip address 10.1.5.2 255.255.255.0
duplex auto
speed auto
!
interface FastEthernet0/1
no ip address
duplex auto
speed auto
shutdown
!
interface Dot11Radio0/0/0
description WAN for mobile
ip address 172.16.10.1 255.255.255.0
speed 12.0 18.0 24.0 36.0 48.0 54.0 6.0 9.0 basic-1.0 basic-11.0 basic-2.0 basic-5.5
ssid ADMIN2
!
interface Dot11Radio0/0/1
no ip address
speed 18.0 36.0 48.0 54.0 9.0 basic-12.0 basic-24.0 basic-6.0
!
interface Serial0/1/0
no ip address
clock rate 2000000
!
interface Serial0/1/1
no ip address
clock rate 2000000
!
interface Vlan1
no ip address
shutdown
!
router rip
version 2
network 10.0.0.0
network 172.16.0.0
!
ip classless
ip route 0.0.0.0 0.0.0.0 10.1.5.1
!
ip flow-export version 9
!
!
!
banner motd ^C this is R3 $
this is R3 ^C
!
!
!
!
!
line con 0
exec-timeout 0 0
password console
logging synchronous
login
!
line aux 0
password aux
login
!
line vty 0 4
password telnet
login
line vty 5 15
password telnet
login
!
!
!
end
to summarize...
the book is a little off here.
-----------------------------------------------------------------------------------------------
R3(config-if)#
int dot11radio0/0/0
R3(config-if)#
ip address 172.16.10.1 255.255.255.0
R3(config-if)#
description WLAN for mobile user
R3(config-if)#
no shut
at this point we have created a wireless interface with an IP address but no SSID exists on this router
interface Dot11Radio0/0/0
description test router 2
ip address 172.16.10.1 255.255.255.0
speed 12.0 18.0 24.0 36.0 48.0 54.0 6.0 9.0 basic-1.0 basic-11.0 basic-2.0 basic-5.5
Trying to use the command "ssid ADMIN" doesnt work here. The below commands are invalid here:
R3(config-if)#
ssid ADMIN
R3(config-if-ssid)#
guest-mode
R3(config-if-ssid)#
authentication open
R3(config-if-ssid)#
ingrastructure-ssid
R3(config-if-ssid)#
exit
-----------------------------------------------------------------------------------------------
We need to drop out of config-if, back to config, and enter SSID config mode
-----------------------------------------------------------------------------------------------
R3(config-if)#
exit
R3(config)#
dot11 ssid ADMIN2 creates an ssid named ADMIN2, and puts us into SSID config mode
R3(config-ssid)#
guest-mode
R3(config-ssid)#
authentication open
then out of config-ssid and back to interface config
R3(config-ssid)#
exit
R3(config)
int dot11r0/0/0
R3(config-if)
?
arp Set arp type (arpa, probe, snap) or timeout or log options
bandwidth Set bandwidth informational parameter
cdp CDP interface subcommands
crypto Encryption/Decryption commands
delay Specify interface throughput delay
description Interface specific description
encryption Configure dot11 encryption parameters
exit Exit from interface configuration mode
fair-queue Enable Fair Queuing on an Interface
hold-queue Set hold queue depth
ip Interface Internet Protocol config commands
mac-address Manually set interface MAC address
mtu Set the interface Maximum Transmission Unit (MTU)
no Negate a command or set its defaults
priority-group Assign a priority group to an interface
service-policy Configure QoS Service Policy
shutdown Shutdown the selected interface
speed Set allowed radio bit rates
ssid Configure radio service set parameters
tx-ring-limit Configure PA level transmit ring limit
we have the option for ssid
R3(config-if)
ssid ADMIN2
%LINK-5-CHANGED: Interface Dot11Radio0/0/0, changed state to administratively down
%LINEPROTO-5-UPDOWN: Line protocol on Interface Dot11Radio0/0/0, changed state to down
%LINK-5-CHANGED: Interface Dot11Radio0/0/0, changed state to up
%LINEPROTO-5-UPDOWN: Line protocol on Interface Dot11Radio0/0/0, changed state to up
the router resets the interface..
-----------------------------------------------------------------------------------------------
R3(config-if)
do show run
[cut]
!
!
dot11 ssid ADMIN2
authentication open
guest-mode
!
!
[cut]
!
interface Dot11Radio0/0/0
description test router 2
ip address 172.16.10.1 255.255.255.0
speed 12.0 18.0 24.0 36.0 48.0 54.0 6.0 9.0 basic-1.0 basic-11.0 basic-2.0 basic-5.5
ssid ADMIN2
!
[cut]
the SSID is created and assigned to the interface
To summarize.
Wrong: create the dot11 interface, then create the SSID from CONFIG-IF mode, which puts you into CONFIG-IF-SSID (there is no such mode on this router) mode, then modify the ssid from there...
Correct: create the dot11 interface. Exit CONFIG-IF and go back to GLOBAL CONFIG. Create the SSID which puts you in CONFIG-SSID mode.
Configure the ssid. Then exit CONFIG-SSID. Back into CONFIG-IF, assign the SSID
We have one more task for R3- Configuring the DHCP pool for wireless clients.
R3(config)#
ip dhcp pool Admin creating the pool name as "Admin"
R3(dhcp-config)#
network 172.16.10.0 255.255.255.0
R3(dhcp-config)#
default-router 172.16.10.1 aka default-gateway for clients in the pool
R3(dhcp-config)#
ip name-server 172.16.10.4 dns server
*automatically exits dhcp-config prompt*
R3(config)#
ip dhcp excluded-address 172.16.10.1 172.16.10.10 excludes the range given
172.16.10.1 is the router interface- we need to specifically exclude it from the pool
this setup should allow the wireless client to pick up an IP after connecting to the open SSID.
However, I was having trouble at first-
even though I seemed to have the SSID set correctly, i was hitting a WEP password prompt
i didnt see any obvious issues with the wifi module im using on the laptop:
The Linksys-WPC300N module provides one 2.4GHz wireless interface suitable for connection to wireless networks.
The module supports protocols that use Ethernet for LAN access.
I ended up creating a new SSID, with the same settings as the original:
R3(config)#
dot11 ssid ADMIN2
R3(config-ssid)#
guest-mode
R3(config-ssid)#
authentication open
and then I assigned the ip address to ssid ADMIN2 instead of the orginal ADMIN ssid
R3(config)#
int dot110/0/0
R3(config-if)#
ip address 172.16.10.1 255.255.255.0
R3(config-if)#
description WLAN for mobile user
R3(config-if)#
no shut
R3(config-if)#
ssid ADMIN2
R3#
show run
Building configuration...
Current configuration : 1467 bytes
!
version 15.1
no service timestamps log datetime msec
no service timestamps debug datetime msec
no service password-encryption
!
hostname R3
!
!
!
enable secret 5 $1$mERr$V5ujdIM9bTB/I.ipB0gkJ0
!
!
ip dhcp excluded-address 172.16.10.1 172.16.10.10
!
ip dhcp pool Admin
network 172.16.10.0 255.255.255.0
default-router 172.16.10.1
!
dot11 ssid ADMIN
authentication open
guest-mode
!
dot11 ssid ADMIN2
authentication open
guest-mode
!
!
!
ip cef
no ipv6 cef
!
!
!
!
license udi pid CISCO2811/K9 sn FTX1017RE40-
!
!
!
!
!
!
!
!
!
no ip domain-lookup
ip name-server 172.16.10.4
!
!
spanning-tree mode pvst
!
!
!
!
!
!
interface FastEthernet0/0
description connection to corp router
ip address 10.1.5.2 255.255.255.0
duplex auto
speed auto
!
interface FastEthernet0/1
no ip address
duplex auto
speed auto
shutdown
!
interface Dot11Radio0/0/0
description WAN for mobile
ip address 172.16.10.1 255.255.255.0
speed 12.0 18.0 24.0 36.0 48.0 54.0 6.0 9.0 basic-1.0 basic-11.0 basic-2.0 basic-5.5
ssid ADMIN2
!
interface Dot11Radio0/0/1
no ip address
speed 18.0 36.0 48.0 54.0 9.0 basic-12.0 basic-24.0 basic-6.0
!
interface Vlan1
no ip address
shutdown
!
ip classless
!
ip flow-export version 9
!
!
!
banner motd ^C this is R3 $
this is R3 ^C
!
!
!
!
!
line con 0
exec-timeout 0 0
password console
logging synchronous
login
!
line aux 0
password aux
login
!
line vty 0 4
password telnet
login
line vty 5 15
password telnet
login
!
!
!
end
Recall the DHCP configuration on R3:
R3(config)#
ip dhcp pool Admin creating the pool name as "Admin"
R3(dhcp-config)#
network 172.16.10.0 255.255.255.0
R3(dhcp-config)#
default-router 172.16.10.1 aka default-gateway for clients in the pool
R3(dhcp-config)#
ip name-server 172.16.10.4 dns server
*automatically exits dhcp-config prompt*
R3(config)#
ip dhcp excluded-address 172.16.10.1 172.16.10.10 excludes the range given
172.16.10.1 is the router interface- we need to specifically exclude it from the pool
we can check the configuration:
R3#
show ip dhcp pool
Pool Admin :
Utilization mark (high/low) : 100 / 0
Subnet size (first/next) : 0 / 0
Total addresses : 254
Leased addresses : 1
Excluded addresses : 1
Pending event : none
1 subnet is currently in the pool
Current index IP address range Leased/Excluded/Total
172.16.10.1 172.16.10.1 - 172.16.10.254 1 / 1 / 254
R3#
show ip dhcp binding
IP address Client-ID/ Lease expiration Type
Hardware address
172.16.10.11 00D0.979A.733B -- Automatic
the show command is becoming more familiar
R3#
show ip?
access-lists List access lists
arp IP ARP table
bgp BGP information
cache IP fast-switching route cache
cef Cisco Express Forwarding
dhcp Show items in the DHCP database
eigrp IP-EIGRP show commands
inspect CBAC (Context Based Access Control) information
interface IP interface status and configuration
ips IPS (Intrusion Prevention System) information
nat IP NAT information
nbar Network-Based Application Recognition
ospf OSPF information
protocols IP routing protocol process parameters and statistics
rip IP RIP show commands
route IP routing table
ssh Information on SSH
we'll use show ip route soon on all the routers. For now, here is the output for R3:
R3#
show ip route
Codes: L - local, C - connected, S - static, R - RIP, M - mobile, B - BGP
D - EIGRP, EX - EIGRP external, O - OSPF, IA - OSPF inter area
N1 - OSPF NSSA external type 1, N2 - OSPF NSSA external type 2
E1 - OSPF external type 1, E2 - OSPF external type 2, E - EGP
i - IS-IS, L1 - IS-IS level-1, L2 - IS-IS level-2, ia - IS-IS inter area
* - candidate default, U - per-user static route, o - ODR
P - periodic downloaded static route
Gateway of last resort is not set
10.0.0.0/8 is variably subnetted, 2 subnets, 2 masks
C 10.1.5.0/24 is directly connected, FastEthernet0/0
L 10.1.5.2/32 is directly connected, FastEthernet0/0
172.16.0.0/16 is variably subnetted, 2 subnets, 2 masks
C 172.16.10.0/24 is directly connected, Dot11Radio0/0/0
L 172.16.10.1/32 is directly connected, Dot11Radio0/0/0
Before moving on to the routing configurations, here is a review of the topology
I have switched over to the DrawIO diagram app to lay out the topology.
The Packet Tracer diagram becomes
too crowded to see the labels; it's labeling system forces awkward positioning of the objects; the interface
label's cant be moved, so if objects are too close together their labels cover eachother.. not good.
DrawIO allows a cleaner layout with plenty of room to label interfaces and ip addresses.
As a compromise, I'll use both.
I have the packet tracer objects spread out just enough to see the interfaces
and the label for each router. From here I can jump into the CLI for each device.
The DrawIO diagram allows me to cleary see IP addresses
I want to also review all of the configurations we just performed:
PROBLEM
The book specifies that of the two serial conections between R1 and Corp, there should be a DCE on each end..
Both of my DCE's are on the same end.
First lets be sure we understand what DCE means:
networkengineering.stackexchange.com/
One side of the link (DCE), has to transmit the clock signal, which controls the data rate, and the other side (DTE) receives the clock signal.
That is good enough for now. Note that while the book does specify in the diagram that each side should have a DCE, it was not actually mentioned in the configs.
We did not set a DCE or clock rate when conifguring those interfaces.
To fix this in my Packet Tracer topology, I did some quick research:
While this post wasnt pertaining to Packet Tracer, it got me thinking about the cable itself.
I deleted both of my existing serial connections and looked at the options for creating a new cable.
I noticed one is a DCE and one is a DTE:
Fixed the issue
back to the configuration overview: 4 routers, abbreviated show run output
Corp
interface FastEthernet0/0
description connection to R3
ip address 10.1.5.1 255.255.255.0
duplex auto
speed auto
!
interface FastEthernet0/1
no ip address
duplex auto
speed auto
shutdown
!
interface Serial0/0/0
description 1st connection to R1
ip address 10.1.2.1 255.255.255.0
!
interface Serial0/0/1
description 2nd connection to R1
ip address 10.1.3.1 255.255.255.0
clock rate 2000000
!
interface Serial0/1/0
description connection to R2
ip address 10.1.4.1 255.255.255.0
!
interface Vlan1
description Switch Card to Core Network
ip address 10.1.1.1 255.255.255.0
!
interface FastEthernet1/0
description switch port connection to WWW Server
switchport mode access
switchport nonegotiate
!
interface FastEthernet1/1
description switch port connection to Email Server
switchport mode access
switchport nonegotiate
!
interface FastEthernet1/2
description switch port connection to DNS Server
switchport mode access
switchport nonegotiate
!
R1
interface FastEthernet0/0
description connection to Finance
ip address 192.168.10.1 255.255.255.0
duplex auto
speed auto
!
interface FastEthernet0/1
description connection to Marketing
ip address 192.168.20.1 255.255.255.0
duplex auto
speed auto
!
interface Serial0/0/0
description 1st connection to Corp router
ip address 10.1.2.2 255.255.255.0
clock rate 2000000
!
interface Serial0/0/1
description 2nd connecction to Corp router
ip address 10.1.3.2 255.255.255.0
!
R2
interface FastEthernet0/0
description Connection to Sales PC
ip address 192.168.30.1 255.255.255.0
duplex auto
speed auto
!
interface FastEthernet0/1
description Connection to HR PC
ip address 192.168.40.1 255.255.255.0
duplex auto
speed auto
!
interface Serial0/0/0
description Connection to Corp Router
ip address 10.1.4.2 255.255.255.0
clock rate 2000000
!
interface Serial0/0/1
no ip address
clock rate 2000000
shutdown
!
R3
interface FastEthernet0/0
description connection to corp router
ip address 10.1.5.2 255.255.255.0
duplex auto
speed auto
!
interface FastEthernet0/1
no ip address
duplex auto
speed auto
shutdown
!
interface Dot11Radio0/0/0
description WAN for mobile
ip address 172.16.10.1 255.255.255.0
speed 12.0 18.0 24.0 36.0 48.0 54.0 6.0 9.0 basic-1.0 basic-11.0 basic-2.0 basic-5.5
ssid ADMIN2
and here is the output of show ip route for each router
Codes: C - connected, S - static, I - IGRP, R - RIP, M - mobile, B - BGP
D - EIGRP, EX - EIGRP external, O - OSPF, IA - OSPF inter area
N1 - OSPF NSSA external type 1, N2 - OSPF NSSA external type 2
E1 - OSPF external type 1, E2 - OSPF external type 2, E - EGP
i - IS-IS, L1 - IS-IS level-1, L2 - IS-IS level-2, ia - IS-IS inter area
* - candidate default, U - per-user static route, o - ODR
P - periodic downloaded static route
Gateway of last resort is not set
Corp
10.0.0.0/24 is subnetted, 2 subnets
C 10.1.2.0 is directly connected, Serial0/0/0
C 10.1.3.0 is directly connected, Serial0/0/1
C 192.168.10.0/24 is directly connected, FastEthernet0/0
C 192.168.20.0/24 is directly connected, FastEthernet0/1
R1
10.0.0.0/24 is subnetted, 2 subnets
C 10.1.2.0 is directly connected, Serial0/0/0
C 10.1.3.0 is directly connected, Serial0/0/1
C 192.168.10.0/24 is directly connected, FastEthernet0/0
C 192.168.20.0/24 is directly connected, FastEthernet0/1
R2
10.0.0.0/24 is subnetted, 1 subnets
C 10.1.4.0 is directly connected, Serial0/0/0
C 192.168.30.0/24 is directly connected, FastEthernet0/0
C 192.168.40.0/24 is directly connected, FastEthernet0/1
R3
10.0.0.0/8 is variably subnetted, 2 subnets, 2 masks
C 10.1.5.0/24 is directly connected, FastEthernet0/0
L 10.1.5.2/32 is directly connected, FastEthernet0/0
172.16.0.0/16 is variably subnetted, 2 subnets, 2 masks
C 172.16.10.0/24 is directly connected, Dot11Radio0/0/0
L 172.16.10.1/32 is directly connected, Dot11Radio0/0/0
Note that this is before we have configured any 'routing'. We are seeing configured, directly connected networks.
The output for R3 is particularly interesting
What does 'variably' subnetted mean, and what is the "L" next to these routes. And why do they have a mask of 32?
R3
10.0.0.0/8 is variably subnetted, 2 subnets, 2 masks
C 10.1.5.0/24 is directly connected, FastEthernet0/0
L 10.1.5.2/32 is directly connected, FastEthernet0/0
172.16.0.0/16 is variably subnetted, 2 subnets, 2 masks
C 172.16.10.0/24 is directly connected, Dot11Radio0/0/0
L 172.16.10.1/32 is directly connected, Dot11Radio0/0/0
Cisco forums
That makes sense, but my question is why did the other routing tables not behave the same way? R3 is the only one that shows "L" routes.
The book tells us we're using two different model routers, and indeed they are running different IOS versions:
NOTE that at the time the book was published IOS 15 was not released yet, so the book assumes all routers are running 12.4
But that still doesnt explain why Corp and R3 are behaving differently..
Corp
10.0.0.0/24 is subnetted, 2 subnets
C 10.1.2.0 is directly connected, Serial0/0/0
C 10.1.3.0 is directly connected, Serial0/0/1
C 192.168.10.0/24 is directly connected, FastEthernet0/0
C 192.168.20.0/24 is directly connected, FastEthernet0/1
R1
10.0.0.0/24 is subnetted, 2 subnets
C 10.1.2.0 is directly connected, Serial0/0/0
C 10.1.3.0 is directly connected, Serial0/0/1
C 192.168.10.0/24 is directly connected, FastEthernet0/0
C 192.168.20.0/24 is directly connected, FastEthernet0/1
R2
10.0.0.0/24 is subnetted, 1 subnets
C 10.1.4.0 is directly connected, Serial0/0/0
C 192.168.30.0/24 is directly connected, FastEthernet0/0
C 192.168.40.0/24 is directly connected, FastEthernet0/1
R3
10.0.0.0/8 is variably subnetted, 2 subnets, 2 masks
C 10.1.5.0/24 is directly connected, FastEthernet0/0
L 10.1.5.2/32 is directly connected, FastEthernet0/0
172.16.0.0/16 is variably subnetted, 2 subnets, 2 masks
C 172.16.10.0/24 is directly connected, Dot11Radio0/0/0
L 172.16.10.1/32 is directly connected, Dot11Radio0/0/0
how are Corp and R3 different?
The answer is, they are not...
I have accidentally displayed the R1 output to the Corp windows. Error in translating data from the IOS to this webpage..
here's the corrected output.
Corp
10.0.0.0/8 is variably subnetted, 10 subnets, 2 masks
C 10.1.1.0/24 is directly connected, Vlan1
L 10.1.1.1/32 is directly connected, Vlan1
C 10.1.2.0/24 is directly connected, Serial0/0/0
L 10.1.2.1/32 is directly connected, Serial0/0/0
C 10.1.3.0/24 is directly connected, Serial0/0/1
L 10.1.3.1/32 is directly connected, Serial0/0/1
C 10.1.4.0/24 is directly connected, Serial0/1/0
L 10.1.4.1/32 is directly connected, Serial0/1/0
C 10.1.5.0/24 is directly connected, FastEthernet0/0
L 10.1.5.1/32 is directly connected, FastEthernet0/0
R1
10.0.0.0/24 is subnetted, 2 subnets
C 10.1.2.0 is directly connected, Serial0/0/0
C 10.1.3.0 is directly connected, Serial0/0/1
C 192.168.10.0/24 is directly connected, FastEthernet0/0
C 192.168.20.0/24 is directly connected, FastEthernet0/1
R2
10.0.0.0/24 is subnetted, 1 subnets
C 10.1.4.0 is directly connected, Serial0/0/0
C 192.168.30.0/24 is directly connected, FastEthernet0/0
C 192.168.40.0/24 is directly connected, FastEthernet0/1
R3
10.0.0.0/8 is variably subnetted, 2 subnets, 2 masks
C 10.1.5.0/24 is directly connected, FastEthernet0/0
L 10.1.5.2/32 is directly connected, FastEthernet0/0
172.16.0.0/16 is variably subnetted, 2 subnets, 2 masks
C 172.16.10.0/24 is directly connected, Dot11Radio0/0/0
L 172.16.10.1/32 is directly connected, Dot11Radio0/0/0
We do indeed see consistent behavior differences between IOS versions 12.4 and 15.1
recap Corp and R3 outputs:
update topology with Router versions
That covers the first half of Chapter 8. Now we are ready to configure IP routing on our network.
There are three ways: Static, Default, Dynamic
To set up static routes, we simply need to program the routes using the ip route command
Syntax
ip route
[
destination network
]
[
mask
]
[
next hop
]
[
exitinterface
]
[
administrative distance
]
[
permanent
]
destination network and mask
the network data we're adding to the routing table
next-hop address
the address of the next-hop router that will receive the packet and forward to the remote network.
This is the IP address of a router interface that is directly connected.
It must be pingable.
exit interface
can be used instead of next hop address
administrative distance
by default, static routes have an admin distance of 1 if you use a next hop, or 0 if you use exit interface.
You can change the value by adding an administrative weight at the end of the command. More on this later with dynamic routing.
permanent
if the interface is shut down or the router cant communicate to the next hp router, the route will automatically be discarded from the table by default.
The 'permanent' option keeps the entry in the routing table indefenitely.
-----------------------------------------------------------------------------------------------------
Corp has automatically picked up 5 routes that are directly connected:
10.1.1.0 to corp switch card
10.1.2.0 to R1
10.1.3.0 to R1
10.1.4.0 to R2
10.1.5.0 to R3
We need to program 5 more routes:
192.168.10.0 traverse R1
192.168.20.0 traverse R1
192.168.30.0 traverse R1
192.168.40.0 traverse R2
172.16.10.0 traverse R3
-----------------------------------------------------------------------------------------------------
R1 has automatically picked up 4 routes that are directly connected:
10.1.2.0
10.1.3.0
192.168.10.0
192.168.20.0
We need to program 6 more routes:
10.1.1.0
10.1.4.0
10.1.5.0
192.168.30.0
192.168.40.0
172.16.10.0
-----------------------------------------------------------------------------------------------------
R2 has automatically picked up 3 routes that are directly connected:
10.1.4.0
192.168.30.0
192.168.40.0
We need to program 7 more routes:
10.1.1.0
10.1.2.0
10.1.3.0
10.1.5.0
192.168.10.0
192.168.20.0
172.16.10.0
-----------------------------------------------------------------------------------------------------
R3 has automatically picked up 2 routes that are directly connected:
10.1.5.0
172.16.10.0
We need to program 8 more routes:
10.1.1.0
10.1.2.0
10.1.3.0
10.1.4.0
192.168.10.0
192.168.20.0
192.168.30.0
192.168.40.0
Notice the pattern- each router ends up with 10 routes
There are 10 routes total in this topology. AKA ten broadcast domains
Programming the routes
Corp
Corp(config)#
ip route 192.168.10.0 255.255.255.0 10.1.2.2 150
Corp(config)#
ip route 192.168.20.0 255.255.255.0 10.1.3.2 150
Corp(config)#
ip route 192.168.30.0 255.255.255.0 10.1.4.2 150
Corp(config)#
ip route 192.168.40.0 255.255.255.0 10.1.4.2 150
Corp(config)#
ip route 172.16.10.0 255.255.255.0 10.1.5.2 150
Corp(config)#
do show ip route
In the first line, the router is saying that a
classful A network is being subnetted
There are 5 routes directly connected
We see two lines per route (one for the network and one
for the interface(/32)-
10.0.0.0/8 is variably subnetted, 10 subnets, 2 masks
C 10.1.1.0/24 is directly connected, Vlan1
L 10.1.1.1/32 is directly connected, Vlan1
C 10.1.2.0/24 is directly connected, Serial0/0/0
L 10.1.2.1/32 is directly connected, Serial0/0/0
C 10.1.3.0/24 is directly connected, Serial0/0/1
L 10.1.3.1/32 is directly connected, Serial0/0/1
C 10.1.4.0/24 is directly connected, Serial0/1/0
L 10.1.4.1/32 is directly connected, Serial0/1/0
C 10.1.5.0/24 is directly connected, FastEthernet0/0
L 10.1.5.1/32 is directly connected, FastEthernet0/0
and 5 routes that require traversal of a router to reach
172.16.0.0/24 is subnetted, 1 subnets
S 172.16.10.0/24 [150/0] via 10.1.5.2
S 192.168.10.0/24 [150/0] via 10.1.2.2
S 192.168.20.0/24 [150/0] via 10.1.3.2
S 192.168.30.0/24 [150/0] via 10.1.4.2
S 192.168.40.0/24 [150/0] via 10.1.4.2
R1
R1(config)#
ip route 10.1.1.0 255.255.255.0 10.1.2.1 150
R1(config)#
ip route 10.1.4.0 255.255.255.0 10.1.3.1 150
R1(config)#
ip route 10.1.5.0 255.255.255.0 10.1.2.1 150
R1(config)#
ip route 192.168.30.0 255.255.255.0 10.1.3.1 150
R1(config)#
ip route 192.168.40.0 255.255.255.0 10.1.2.1 150
R1(config)#
ip route 172.16.10.0 255.255.255.0 10.1.3.1 150
the only way to get across the corp router is to go into it via 10.1.2.1 or 10.1.3.1
R1(config)#
do show ip route
10.0.0.0/24 is subnetted, 5 subnets
S 10.1.1.0 [150/0] via 10.1.2.1
C 10.1.2.0 is directly connected, Serial0/0/0
C 10.1.3.0 is directly connected, Serial0/0/1
S 10.1.4.0 [150/0] via 10.1.3.1
S 10.1.5.0 [150/0] via 10.1.2.1
172.16.0.0/24 is subnetted, 1 subnets
S 172.16.10.0 [150/0] via 10.1.3.1
C 192.168.10.0/24 is directly connected, FastEthernet0/0
C 192.168.20.0/24 is directly connected, FastEthernet0/1
S 192.168.30.0/24 [150/0] via 10.1.3.1
S 192.168.40.0/24 [150/0] via 10.1.2.1
R2
R2(config)#
iproute 10.1.1.0 255.255.255.0 10.1.4.1 150
R2(config)#
iproute 10.1.2.0 255.255.255.0 10.1.4.1 150
R2(config)#
iproute 10.1.3.0 255.255.255.0 10.1.4.1 150
R2(config)#
iproute 10.1.5.0 255.255.255.0 10.1.4.1 150
R2(config)#
iproute 192.168.10.0 255.255.255.0 10.1.4.1 150
R2(config)#
iproute 192.168.20.0 255.255.255.0 10.1.4.1 150
the only way to get across Corp is to go into it via 10.1.4.1
R2(config)#
do show ip route
10.0.0.0/24 is subnetted, 5 subnets
S 10.1.1.0 [150/0] via 10.1.4.1
S 10.1.2.0 [150/0] via 10.1.4.1
S 10.1.3.0 [150/0] via 10.1.4.1
C 10.1.4.0 is directly connected, Serial0/0/0
S 10.1.5.0 [150/0] via 10.1.4.1
172.16.0.0/24 is subnetted, 1 subnets
S 172.16.10.0 [150/0] via 10.1.4.1
S 192.168.10.0/24 [150/0] via 10.1.4.1
S 192.168.20.0/24 [150/0] via 10.1.4.1
C 192.168.30.0/24 is directly connected, FastEthernet0/0
C 192.168.40.0/24 is directly connected, FastEthernet0/1
R3
R3(config)#
ip route 10.1.1.0 255.255.255.0 fastethernet 0/0 150
R3(config)#
ip route 10.1.2.0 255.255.255.0 fastethernet 0/0 150
R3(config)#
ip route 10.1.3.0 255.255.255.0 fastethernet 0/0 150
R3(config)#
ip route 10.1.4.0 255.255.255.0 fastethernet 0/0 150
R3(config)#
ip route 192.168.10.0 255.255.255.0 fastethernet 0/0 150
R3(config)#
ip route 192.168.20.0 255.255.255.0 fastethernet 0/0 150
R3(config)#
ip route 192.168.30.0 255.255.255.0 fastethernet 0/0 150
R3(config)#
ip route 192.168.40.0 255.255.255.0 fastethernet 0/0 150
the only way to get across Corp is to EXIT R3 via F0/0
R3(config)#
do show ip route
10.0.0.0/8 is variably subnetted, 6 subnets, 2 masks
S 10.1.1.0/24 is directly connected, FastEthernet0/0
S 10.1.2.0/24 is directly connected, FastEthernet0/0
S 10.1.3.0/24 is directly connected, FastEthernet0/0
S 10.1.4.0/24 is directly connected, FastEthernet0/0
C 10.1.5.0/24 is directly connected, FastEthernet0/0
L 10.1.5.2/32 is directly connected, FastEthernet0/0
172.16.0.0/16 is variably subnetted, 2 subnets, 2 masks
C 172.16.10.0/24 is directly connected, Dot11Radio0/0/0
L 172.16.10.1/32 is directly connected, Dot11Radio0/0/0
S 192.168.10.0/24 is directly connected, FastEthernet0/0
S 192.168.20.0/24 is directly connected, FastEthernet0/0
S 192.168.30.0/24 is directly connected, FastEthernet0/0
S 192.168.40.0/24 is directly connected, FastEthernet0/0
before verifying connectivity across the network, we need to make sure all of our hosts are set. The book is giving us the IP addresses for the servers:
Server Gateway 10.1.1.1
ServerWeb 10.1.1.2
ServerEmail 10.1.1.3
ServerDNS 10.1.1.4
Now we can do some testing across the network:
R3#
ping 10.1.2.2
traverse Corp to R1
R3#
ping 10.1.1.1
traverse Corp to a Corp interface we arent directly connected to
R3#
ping 10.1.1.2
traverse Corp to Web server
R3#
ping 10.1.1.3
traverse Corp to Email server
R3#
ping 10.1.1.4
traverse Corp to DNS server
MobileUser
ping 192.168.10.2
traverse R3, Corp, R1 to Finance client
MobileUser
tracert 192.168.10.2
traverse R3, Corp, R1 to Finance client
Tracing route to 192.168.10.2 over a maximum of 30 hops:
1 19 ms 5 ms 20 ms 172.16.10.1
2 20 ms 6 ms 11 ms 10.1.5.1
3 11 ms 15 ms 10 ms 10.1.3.2
4 9 ms 13 ms 22 ms 192.168.10.2
Trace complete.
notice how the trace doesnt count an egress as a hop, only an ingress
ALSO NOTE that tracert is a Windows command.
the IOS equivalent is traceroute
notice how the output differs from the Windows command
R3
traceroute 192.168.10.2
Type escape sequence to abort.
Tracing the route to 192.168.10.2
1 10.1.5.1 0 msec 0 msec 0 msec
2 10.1.2.2 6 msec 0 msec 5 msec
3 192.168.10.2 1 msec 4 msec 3 msec
Default Routing
we could have done this on R3
R3(config)#
ip route 0.0.0.0 0.0.0.0 10.1.5.1
as an alternative to this configuration on R3
R3(config)#
ip route 10.1.1.0 255.255.255.0 fastethernet 0/0 150
R3(config)#
ip route 10.1.2.0 255.255.255.0 fastethernet 0/0 150
R3(config)#
ip route 10.1.3.0 255.255.255.0 fastethernet 0/0 150
R3(config)#
ip route 10.1.4.0 255.255.255.0 fastethernet 0/0 150
R3(config)#
ip route 192.168.10.0 255.255.255.0 fastethernet 0/0 150
R3(config)#
ip route 192.168.20.0 255.255.255.0 fastethernet 0/0 150
R3(config)#
ip route 192.168.30.0 255.255.255.0 fastethernet 0/0 150
R3(config)#
ip route 192.168.40.0 255.255.255.0 fastethernet 0/0 150
the only way to get across Corp is to EXIT R3 via F0/0
This is called default routing. It should only be used on 'stub routers'- those with only one exit path out of the network.
if you try to put a default route on a non-stub router, you could create loops, since there will be more than one path to other routers...
Think of a default route as a static route that uses a wildcard address and mask. The wildcard is 0.0.0.0
to further analyze this comparison, I'm going to remove the routes from R3...
R3(config)#
no ip route 10.1.1.0 255.255.255.0 fastethernet0/0 150
R3(config)#
no ip route 10.1.2.0 255.255.255.0 fastethernet0/0 150
R3(config)#
no ip route 10.1.3.0 255.255.255.0 fastethernet0/0 150
R3(config)#
no ip route 10.1.4.0 255.255.255.0 fastethernet0/0 150
R3(config)#
no ip route 192.168.10.0 255.255.255.0 fastethernet0/0 150
R3(config)#
no ip route 192.168.20.0 255.255.255.0 fastethernet0/0 150
R3(config)#
no ip route 192.168.30.0 255.255.255.0 fastethernet0/0 150
R3(config)#
no ip route 192.168.40.0 255.255.255.0 fastethernet0/0 150
and then set the default route instead.
R3#
ip route 0.0.0.0 0.0.0.0 10.1.5.1 --- ingress at next hop
OR
R3#
ip route 0.0.0.0 0.0.0.0 Fa0/0 --- egress interface
Then compare the output of show ip route
static routes set
R3#
show ip route
Gateway of last resort is not set
10.0.0.0/8 is variably subnetted, 6 subnets, 2 masks
S 10.1.1.0/24 is directly connected, FastEthernet0/0
S 10.1.2.0/24 is directly connected, FastEthernet0/0
S 10.1.3.0/24 is directly connected, FastEthernet0/0
S 10.1.4.0/24 is directly connected, FastEthernet0/0
C 10.1.5.0/24 is directly connected, FastEthernet0/0
L 10.1.5.2/32 is directly connected, FastEthernet0/0
172.16.0.0/16 is variably subnetted, 2 subnets, 2 masks
C 172.16.10.0/24 is directly connected, Dot11Radio0/0/0
L 172.16.10.1/32 is directly connected, Dot11Radio0/0/0
S 192.168.10.0/24 is directly connected, FastEthernet0/0
S 192.168.20.0/24 is directly connected, FastEthernet0/0
S 192.168.30.0/24 is directly connected, FastEthernet0/0
S 192.168.40.0/24 is directly connected, FastEthernet0/0
default route set
R3#
show ip route
Gateway of last resort is 10.1.5.1 to network 0.0.0.0
10.0.0.0/8 is variably subnetted, 2 subnets, 2 masks
C 10.1.5.0/24 is directly connected, FastEthernet0/0
L 10.1.5.2/32 is directly connected, FastEthernet0/0
172.16.0.0/16 is variably subnetted, 2 subnets, 2 masks
C 172.16.10.0/24 is directly connected, Dot11Radio0/0/0
L 172.16.10.1/32 is directly connected, Dot11Radio0/0/0
S* 0.0.0.0/0 [1/0] via 10.1.5.1
two directly connected networks- 10.1.5.0 and 172.16.10.0
anything not included in those networks goes to ingress of attached neighbor Corp 10.1.5.1
in this toplogy, that includes:
192.168.10.0
192.168.20.0
192.168.30.0
192.168.40.0
and
10.1.1.0
10.1.2.0
10.1.3.0
10.1.4.0
RIP Routing Information Protocol
R1(config)#
router ?
bgp Border Gateway Protocol (BGP)
eigrp Enhanced Interior Gateway Routing Protocol (EIGRP)
ospf Open Shortest Path First (OSPF)
rip Routing Information Protocol (RIP)
set RIP on Corp
Corp(config)#
router rip
Corp(config-router)#
network 10.0.0.0
set RIP on R1
R1(config)#
router rip
R1(config-router)#
network 10.0.0.0
R1 routing table
R1(config)#
do show ip route
10.0.0.0/24 is subnetted, 5 subnets
R 10.1.1.0 [120/1] via 10.1.2.1, 00:00:21, Serial0/0/0
[120/1] via 10.1.3.1, 00:00:21, Serial0/0/1
C 10.1.2.0 is directly connected, Serial0/0/0
C 10.1.3.0 is directly connected, Serial0/0/1
R 10.1.4.0 [120/1] via 10.1.2.1, 00:00:21, Serial0/0/0
[120/1] via 10.1.3.1, 00:00:21, Serial0/0/1
R 10.1.5.0 [120/1] via 10.1.2.1, 00:00:21, Serial0/0/0
[120/1] via 10.1.3.1, 00:00:21, Serial0/0/1
172.16.0.0/24 is subnetted, 1 subnets
S 172.16.10.0 [150/0] via 10.1.3.1
C 192.168.10.0/24 is directly connected, FastEthernet0/0
C 192.168.20.0/24 is directly connected, FastEthernet0/1
S 192.168.30.0/24 [150/0] via 10.1.3.1
S 192.168.40.0/24 [150/0] via 10.1.2.1
here's R1 before RIP, with only static routes set:
R1(config)#
do show ip route
10.0.0.0/24 is subnetted, 5 subnets
S 10.1.1.0 [150/0] via 10.1.2.1
C 10.1.2.0 is directly connected, Serial0/0/0
C 10.1.3.0 is directly connected, Serial0/0/1
S 10.1.4.0 [150/0] via 10.1.3.1
S 10.1.5.0 [150/0] via 10.1.2.1
172.16.0.0/24 is subnetted, 1 subnets
S 172.16.10.0 [150/0] via 10.1.3.1
C 192.168.10.0/24 is directly connected, FastEthernet0/0
C 192.168.20.0/24 is directly connected, FastEthernet0/1
S 192.168.30.0/24 [150/0] via 10.1.3.1
S 192.168.40.0/24 [150/0] via 10.1.2.1
These RIP routes are being advertised as available *to other RIP routers*.
CORP is advertisting THREE routes via RIP to R1 right now
10.1.1.0
10.1.4.0
10.1.5.0
access to those networks can be achieved by R1 by going THROUGH CORP via ingress .2.1 or .3.1
The advantage..... is that we didnt statically program these routes
we engaged RIP, on BOTH routers- R1 and Corp, and handed them BOTH the network "10.0.0.0"
So, why did RIP choose to display these particular routes
Keep in mind that the output above is from R1 only... In the context of the R1 ROUTER ONLY,
there are three relevant routes within the "10.0.0.0" parameter we specified. The three routes involve Corp.
Corp is sending RIP data about these routes to Corp.
Lets look closer at how this is happening:
here's our starting point before any RIP is set
here's our routing tables after i set RIP with 10.0.0.0 on both..
FIRST i set it on Corp, then R1.(per the book's instructions) As a result we are seeing RIP routes in R1 only....
then I went back to a fresh packet tracer file with no RIP set. And I set RIP in the opposite order;
FIRST i set it on R1, then Corp. And again, we are seeing RIP routes in R1 only....
I wanted to prove that it didnt matter which order we enabled RIP on the two routers. What matters here is that
we enable RIP on both of them with the criteria of 10.0.0.0
Recall the topology:
if Corp and R1 are set for RIP and given the criteria 10.0.0.0, meaning that we are trying to reach networks
within that range, then it follows that Corp will advertise 1.1.0, 1.4.0, and 1.5.0 to R1, because Corp stands between those networks
and R1
"Hi R1, I'm Corp I have three networks that fall inside 10.0.0.0, and you can reach them through me via .2.1 or .3.1"
It also follows that Corp's routing table shows no RIP routes- because R1 isnt advertising any. R1 doesnt have any networks
in the 10.0.0.0 range that Corp could reach
To further clarify this, we'll proceed with the book's instructions. We'll now set more RIP routes on R1
R1(config)#
router rip
R1(config-router)#
network 192.168.10.0
R1(config-router)#
network 192.168.20.0
Corp routing table before RIP set on R1:
Corp#
show ip route
10.0.0.0/8 is variably subnetted, 10 subnets, 2 masks
C 10.1.1.0/24 is directly connected, Vlan1
L 10.1.1.1/32 is directly connected, Vlan1
C 10.1.2.0/24 is directly connected, Serial0/0/0
L 10.1.2.1/32 is directly connected, Serial0/0/0
C 10.1.3.0/24 is directly connected, Serial0/0/1
L 10.1.3.1/32 is directly connected, Serial0/0/1
C 10.1.4.0/24 is directly connected, Serial0/1/0
L 10.1.4.1/32 is directly connected, Serial0/1/0
C 10.1.5.0/24 is directly connected, FastEthernet0/0
L 10.1.5.1/32 is directly connected, FastEthernet0/0
172.16.0.0/24 is subnetted, 1 subnets
S 172.16.10.0/24 [150/0] via 10.1.5.2
S 192.168.10.0/24 [150/0] via 10.1.2.2
S 192.168.20.0/24 [150/0] via 10.1.3.2
S 192.168.30.0/24 [150/0] via 10.1.4.2
S 192.168.40.0/24 [150/0] via 10.1.4.2
Corp routing table after RIP set on R1:
Gateway of last resort is not set
10.0.0.0/8 is variably subnetted, 10 subnets, 2 masks
C 10.1.1.0/24 is directly connected, Vlan1
L 10.1.1.1/32 is directly connected, Vlan1
C 10.1.2.0/24 is directly connected, Serial0/0/0
L 10.1.2.1/32 is directly connected, Serial0/0/0
C 10.1.3.0/24 is directly connected, Serial0/0/1
L 10.1.3.1/32 is directly connected, Serial0/0/1
C 10.1.4.0/24 is directly connected, Serial0/1/0
L 10.1.4.1/32 is directly connected, Serial0/1/0
C 10.1.5.0/24 is directly connected, FastEthernet0/0
L 10.1.5.1/32 is directly connected, FastEthernet0/0
nothing changed so far
172.16.0.0/24 is subnetted, 1 subnets
S 172.16.10.0/24 [150/0] via 10.1.5.2
no change
R 192.168.10.0/24 [120/1] via 10.1.2.2, 00:00:08, Serial0/0/0
[120/1] via 10.1.3.2, 00:00:08, Serial0/0/1
RIP overrides static- 2 paths available now
R 192.168.20.0/24 [120/1] via 10.1.2.2, 00:00:08, Serial0/0/0
[120/1] via 10.1.3.2, 00:00:08, Serial0/0/1
RIP overrides static- 2 paths available now
S 192.168.30.0/24 [150/0] via 10.1.4.2
no change
S 192.168.40.0/24 [150/0] via 10.1.4.2
no change
"Hi Corp- I'm R1 and I have zero networks
that fall inside 10.0.0.0, however I do have some networks that fall within
192.168.20.0 and 192.168.10.0
and you can reach them through me(R1) if you ingress at .1.2.2 or .1.3.2"
ok, we have the concept down. Time to proceed and set up RIP on R2............
R2(config)#
router rip
R2(config-router)#
network 10.0.0.0
R2(config-router)#
network 192.168.30.0
R2(config-router)#
network 192.168.40.0
R2 before RIP enabled
R2#
show ip route
10.0.0.0/24 is subnetted, 5 subnets
S 10.1.1.0 [150/0] via 10.1.4.1
S 10.1.2.0 [150/0] via 10.1.4.1
S 10.1.3.0 [150/0] via 10.1.4.1
C 10.1.4.0 is directly connected, Serial0/0/0
S 10.1.5.0 [150/0] via 10.1.4.1
172.16.0.0/24 is subnetted, 1 subnets
S 172.16.10.0 [150/0] via 10.1.4.1
S 192.168.10.0/24 [150/0] via 10.1.4.1
S 192.168.20.0/24 [150/0] via 10.1.4.1
C 192.168.30.0/24 is directly connected, FastEthernet0/0
C 192.168.40.0/24 is directly connected, FastEthernet0/1
R2 after RIP added
R2#
show ip route
10.0.0.0/24 is subnetted, 5 subnets
R 10.1.1.0 [120/1] via 10.1.4.1, 00:00:24, Serial0/0/0
from corp
R 10.1.2.0 [120/1] via 10.1.4.1, 00:00:24, Serial0/0/0
from corp
R 10.1.3.0 [120/1] via 10.1.4.1, 00:00:24, Serial0/0/0
from corp
C 10.1.4.0 is directly connected, Serial0/0/0
R 10.1.5.0 [120/1] via 10.1.4.1, 00:00:24, Serial0/0/0
from corp
172.16.0.0/24 is subnetted, 1 subnets
S 172.16.10.0 [150/0] via 10.1.4.1
R 192.168.10.0/24 [120/2] via 10.1.4.1, 00:00:24, Serial0/0/0
from R1 via corp
R 192.168.20.0/24 [120/2] via 10.1.4.1, 00:00:24, Serial0/0/0
from R1 via corp
C 192.168.30.0/24 is directly connected, FastEthernet0/0
C 192.168.40.0/24 is directly connected, FastEthernet0/1
now lets compare the Corp and R1 routing tables- before RIP was set on R2 and after
Corp before R2 RIP
Corp#
show ip route
10.0.0.0/8 is variably subnetted, 10 subnets, 2 masks
C 10.1.1.0/24 is directly connected, Vlan1
L 10.1.1.1/32 is directly connected, Vlan1
C 10.1.2.0/24 is directly connected, Serial0/0/0
L 10.1.2.1/32 is directly connected, Serial0/0/0
C 10.1.3.0/24 is directly connected, Serial0/0/1
L 10.1.3.1/32 is directly connected, Serial0/0/1
C 10.1.4.0/24 is directly connected, Serial0/1/0
L 10.1.4.1/32 is directly connected, Serial0/1/0
C 10.1.5.0/24 is directly connected, FastEthernet0/0
L 10.1.5.1/32 is directly connected, FastEthernet0/0
172.16.0.0/24 is subnetted, 1 subnets
S 172.16.10.0/24 [150/0] via 10.1.5.2
R 192.168.10.0/24 [120/1] via 10.1.2.2, 00:00:02, Serial0/0/0
[120/1] via 10.1.3.2, 00:00:02, Serial0/0/1
R 192.168.20.0/24 [120/1] via 10.1.2.2, 00:00:02, Serial0/0/0
[120/1] via 10.1.3.2, 00:00:02, Serial0/0/1
from R1
S 192.168.30.0/24 [150/0] via 10.1.4.2
S 192.168.40.0/24 [150/0] via 10.1.4.2
Corp after R2 RIP
Corp#
show ip route
10.0.0.0/8 is variably subnetted, 10 subnets, 2 masks
C 10.1.1.0/24 is directly connected, Vlan1
L 10.1.1.1/32 is directly connected, Vlan1
C 10.1.2.0/24 is directly connected, Serial0/0/0
L 10.1.2.1/32 is directly connected, Serial0/0/0
C 10.1.3.0/24 is directly connected, Serial0/0/1
L 10.1.3.1/32 is directly connected, Serial0/0/1
C 10.1.4.0/24 is directly connected, Serial0/1/0
L 10.1.4.1/32 is directly connected, Serial0/1/0
C 10.1.5.0/24 is directly connected, FastEthernet0/0
L 10.1.5.1/32 is directly connected, FastEthernet0/0
172.16.0.0/24 is subnetted, 1 subnets
S 172.16.10.0/24 [150/0] via 10.1.5.2
R 192.168.10.0/24 [120/1] via 10.1.2.2, 00:00:19, Serial0/0/0
[120/1] via 10.1.3.2, 00:00:19, Serial0/0/1
R 192.168.20.0/24 [120/1] via 10.1.2.2, 00:00:19, Serial0/0/0
[120/1] via 10.1.3.2, 00:00:19, Serial0/0/1
from R1
R 192.168.30.0/24 [120/1] via 10.1.4.2, 00:00:15, Serial0/1/0
R 192.168.40.0/24 [120/1] via 10.1.4.2, 00:00:15, Serial0/1/0
from R2
RIP on R2 is advertising .30.0 and .40.0 to Corp
R1 before R2 RIP
R1#
show ip route
10.0.0.0/24 is subnetted, 5 subnets
R 10.1.1.0 [120/1] via 10.1.2.1, 00:00:05, Serial0/0/0
[120/1] via 10.1.3.1, 00:00:05, Serial0/0/1
from Corp
C 10.1.2.0 is directly connected, Serial0/0/0
C 10.1.3.0 is directly connected, Serial0/0/1
R 10.1.4.0 [120/1] via 10.1.2.1, 00:00:05, Serial0/0/0
[120/1] via 10.1.3.1, 00:00:05, Serial0/0/1
R 10.1.5.0 [120/1] via 10.1.2.1, 00:00:05, Serial0/0/0
[120/1] via 10.1.3.1, 00:00:05, Serial0/0/1
from Corp
172.16.0.0/24 is subnetted, 1 subnets
S 172.16.10.0 [150/0] via 10.1.3.1
C 192.168.10.0/24 is directly connected, FastEthernet0/0
C 192.168.20.0/24 is directly connected, FastEthernet0/1
S 192.168.30.0/24 [150/0] via 10.1.3.1
S 192.168.40.0/24 [150/0] via 10.1.2.1
R1 after R2 RIP
R1#
show ip route
10.0.0.0/24 is subnetted, 5 subnets
R 10.1.1.0 [120/1] via 10.1.2.1, 00:00:06, Serial0/0/0
[120/1] via 10.1.3.1, 00:00:06, Serial0/0/1
from Corp
C 10.1.2.0 is directly connected, Serial0/0/0
C 10.1.3.0 is directly connected, Serial0/0/1
R 10.1.4.0 [120/1] via 10.1.2.1, 00:00:06, Serial0/0/0
[120/1] via 10.1.3.1, 00:00:06, Serial0/0/1
R 10.1.5.0 [120/1] via 10.1.2.1, 00:00:06, Serial0/0/0
[120/1] via 10.1.3.1, 00:00:06, Serial0/0/1
from Corp
172.16.0.0/24 is subnetted, 1 subnets
S 172.16.10.0 [150/0] via 10.1.3.1
C 192.168.10.0/24 is directly connected, FastEthernet0/0
C 192.168.20.0/24 is directly connected, FastEthernet0/1
R 192.168.30.0/24 [120/2] via 10.1.3.1, 00:00:06, Serial0/0/1
[120/2] via 10.1.2.1, 00:00:06, Serial0/0/0
R 192.168.40.0/24 [120/2] via 10.1.2.1, 00:00:06, Serial0/0/0
[120/2] via 10.1.3.1, 00:00:06, Serial0/0/1
from R2 via Corp
Now to set RIP on R3
R3(config)#
router rip
R3(config-router)#
network 10.0.0.0
R3(config-router)#
network 172.16.0.0
note that R3 is our only router with "gateway of last resort" set because we set a default route instead of static routes
As a result, we only see directly connected routes listed, along with a single "S*" for the default gateway
R3 before RIP
R3#
show ip route
Gateway of last resort is 10.1.5.1 to network 0.0.0.0
10.0.0.0/8 is variably subnetted, 2 subnets, 2 masks
C 10.1.5.0/24 is directly connected, FastEthernet0/0
L 10.1.5.2/32 is directly connected, FastEthernet0/0
172.16.0.0/16 is variably subnetted, 2 subnets, 2 masks
C 172.16.10.0/24 is directly connected, Dot11Radio0/0/0
L 172.16.10.1/32 is directly connected, Dot11Radio0/0/0
S* 0.0.0.0/0 [1/0] via 10.1.5.1
R3 after RIP
R3#
show ip route
Gateway of last resort is 10.1.5.1 to network 0.0.0.0
-------------------------------------------------------------
10.0.0.0/8 is variably subnetted, 6 subnets, 2 masks
R 10.1.1.0/24 [120/1] via 10.1.5.1, 00:00:21, FastEthernet0/0
R 10.1.2.0/24 [120/1] via 10.1.5.1, 00:00:21, FastEthernet0/0
R 10.1.3.0/24 [120/1] via 10.1.5.1, 00:00:21, FastEthernet0/0
R 10.1.4.0/24 [120/1] via 10.1.5.1, 00:00:21, FastEthernet0/0
from Corp
C 10.1.5.0/24 is directly connected, FastEthernet0/0
L 10.1.5.2/32 is directly connected, FastEthernet0/0
-------------------------------------------------------------
172.16.0.0/16 is variably subnetted, 2 subnets, 2 masks
C 172.16.10.0/24 is directly connected, Dot11Radio0/0/0
L 172.16.10.1/32 is directly connected, Dot11Radio0/0/0
R 192.168.10.0/24 [120/2] via 10.1.5.1, 00:00:21, FastEthernet0/0
R 192.168.20.0/24 [120/2] via 10.1.5.1, 00:00:21, FastEthernet0/0
From R1 via Corp
R 192.168.30.0/24 [120/2] via 10.1.5.1, 00:00:21, FastEthernet0/0
R 192.168.40.0/24 [120/2] via 10.1.5.1, 00:00:21, FastEthernet0/0
From R2 via Corp
S* 0.0.0.0/0 [1/0] via 10.1.5.1
Corp before R3 RIP
Corp#
show ip route
10.0.0.0/8 is variably subnetted, 10 subnets, 2 masks
C 10.1.1.0/24 is directly connected, Vlan1
L 10.1.1.1/32 is directly connected, Vlan1
C 10.1.2.0/24 is directly connected, Serial0/0/0
L 10.1.2.1/32 is directly connected, Serial0/0/0
C 10.1.3.0/24 is directly connected, Serial0/0/1
L 10.1.3.1/32 is directly connected, Serial0/0/1
C 10.1.4.0/24 is directly connected, Serial0/1/0
L 10.1.4.1/32 is directly connected, Serial0/1/0
C 10.1.5.0/24 is directly connected, FastEthernet0/0
L 10.1.5.1/32 is directly connected, FastEthernet0/0
172.16.0.0/24 is subnetted, 1 subnets
S 172.16.10.0/24 [150/0] via 10.1.5.2
R 192.168.10.0/24 [120/1] via 10.1.2.2, 00:00:26, Serial0/0/0
[120/1] via 10.1.3.2, 00:00:26, Serial0/0/1
R 192.168.20.0/24 [120/1] via 10.1.2.2, 00:00:26, Serial0/0/0
[120/1] via 10.1.3.2, 00:00:26, Serial0/0/1
from R1 via corp
R 192.168.30.0/24 [120/1] via 10.1.4.2, 00:00:21, Serial0/1/0
R 192.168.40.0/24 [120/1] via 10.1.4.2, 00:00:21, Serial0/1/0
from R2 via corp
Corp after R3 RIP
Corp#
show ip route
10.0.0.0/8 is variably subnetted, 10 subnets, 2 masks
C 10.1.1.0/24 is directly connected, Vlan1
L 10.1.1.1/32 is directly connected, Vlan1
C 10.1.2.0/24 is directly connected, Serial0/0/0
L 10.1.2.1/32 is directly connected, Serial0/0/0
C 10.1.3.0/24 is directly connected, Serial0/0/1
L 10.1.3.1/32 is directly connected, Serial0/0/1
C 10.1.4.0/24 is directly connected, Serial0/1/0
L 10.1.4.1/32 is directly connected, Serial0/1/0
C 10.1.5.0/24 is directly connected, FastEthernet0/0
L 10.1.5.1/32 is directly connected, FastEthernet0/0
172.16.0.0/16 is variably subnetted, 2 subnets, 2 masks
R 172.16.0.0/16 [120/1] via 10.1.5.2, 00:00:13, FastEthernet0/0
S 172.16.10.0/24 [150/0] via 10.1.5.2
from R3
R 192.168.10.0/24 [120/1] via 10.1.3.2, 00:00:13, Serial0/0/1
[120/1] via 10.1.2.2, 00:00:13, Serial0/0/0
R 192.168.20.0/24 [120/1] via 10.1.3.2, 00:00:13, Serial0/0/1
[120/1] via 10.1.2.2, 00:00:13, Serial0/0/0
from R1 via corp
R 192.168.30.0/24 [120/1] via 10.1.4.2, 00:00:24, Serial0/1/0
R 192.168.40.0/24 [120/1] via 10.1.4.2, 00:00:24, Serial0/1/0
from R2 via corp
R2 before R3 RIP
R2#
show ip route
10.0.0.0/24 is subnetted, 5 subnets
R 10.1.1.0 [120/1] via 10.1.4.1, 00:00:15, Serial0/0/0
R 10.1.2.0 [120/1] via 10.1.4.1, 00:00:15, Serial0/0/0
R 10.1.3.0 [120/1] via 10.1.4.1, 00:00:15, Serial0/0/0
from Corp
C 10.1.4.0 is directly connected, Serial0/0/0
R 10.1.5.0 [120/1] via 10.1.4.1, 00:00:15, Serial0/0/0
from Corp
172.16.0.0/24 is subnetted, 1 subnets
S 172.16.10.0 [150/0] via 10.1.4.1
R 192.168.10.0/24 [120/2] via 10.1.4.1, 00:00:15, Serial0/0/0
R 192.168.20.0/24 [120/2] via 10.1.4.1, 00:00:15, Serial0/0/0
from R1 via Corp
C 192.168.30.0/24 is directly connected, FastEthernet0/0
C 192.168.40.0/24 is directly connected, FastEthernet0/1
R2 after R3 RIP
R2#
show ip route
10.0.0.0/24 is subnetted, 5 subnets
R 10.1.1.0 [120/1] via 10.1.4.1, 00:00:20, Serial0/0/0
R 10.1.2.0 [120/1] via 10.1.4.1, 00:00:20, Serial0/0/0
R 10.1.3.0 [120/1] via 10.1.4.1, 00:00:20, Serial0/0/0
from Corp
C 10.1.4.0 is directly connected, Serial0/0/0
R 10.1.5.0 [120/1] via 10.1.4.1, 00:00:20, Serial0/0/0
from Corp
172.16.0.0/16 is variably subnetted, 2 subnets, 2 masks
R 172.16.0.0/16 [120/2] via 10.1.4.1, 00:00:20, Serial0/0/0
S 172.16.10.0/24 [150/0] via 10.1.4.1
from R3 via Corp
R 192.168.10.0/24 [120/2] via 10.1.4.1, 00:00:20, Serial0/0/0
R 192.168.20.0/24 [120/2] via 10.1.4.1, 00:00:20, Serial0/0/0
from R1 via Corp
C 192.168.30.0/24 is directly connected, FastEthernet0/0
C 192.168.40.0/24 is directly connected, FastEthernet0/1
R1 before R3 RIP
R1#
show ip route
10.0.0.0/24 is subnetted, 5 subnets
R 10.1.1.0 [120/1] via 10.1.2.1, 00:00:04, Serial0/0/0
[120/1] via 10.1.3.1, 00:00:04, Serial0/0/1
C 10.1.2.0 is directly connected, Serial0/0/0
C 10.1.3.0 is directly connected, Serial0/0/1
R 10.1.4.0 [120/1] via 10.1.2.1, 00:00:04, Serial0/0/0
[120/1] via 10.1.3.1, 00:00:04, Serial0/0/1
R 10.1.5.0 [120/1] via 10.1.2.1, 00:00:04, Serial0/0/0
[120/1] via 10.1.3.1, 00:00:04, Serial0/0/1
from Corp
172.16.0.0/24 is subnetted, 1 subnets
S 172.16.10.0 [150/0] via 10.1.3.1
C 192.168.10.0/24 is directly connected, FastEthernet0/0
C 192.168.20.0/24 is directly connected, FastEthernet0/1
R 192.168.30.0/24 [120/2] via 10.1.2.1, 00:00:04, Serial0/0/0
[120/2] via 10.1.3.1, 00:00:04, Serial0/0/1
R 192.168.40.0/24 [120/2] via 10.1.2.1, 00:00:04, Serial0/0/0
[120/2] via 10.1.3.1, 00:00:04, Serial0/0/1
from R2 via Corp
R1 after R3 RIP
R1#
show ip route
10.0.0.0/24 is subnetted, 5 subnets
R 10.1.1.0 [120/1] via 10.1.3.1, 00:00:03, Serial0/0/1
[120/1] via 10.1.2.1, 00:00:03, Serial0/0/0
C 10.1.2.0 is directly connected, Serial0/0/0
C 10.1.3.0 is directly connected, Serial0/0/1
R 10.1.4.0 [120/1] via 10.1.3.1, 00:00:03, Serial0/0/1
[120/1] via 10.1.2.1, 00:00:03, Serial0/0/0
R 10.1.5.0 [120/1] via 10.1.3.1, 00:00:03, Serial0/0/1
[120/1] via 10.1.2.1, 00:00:03, Serial0/0/0
from Corp
172.16.0.0/16 is variably subnetted, 2 subnets, 2 masks
R 172.16.0.0/16 [120/2] via 10.1.3.1, 00:00:03, Serial0/0/1
[120/2] via 10.1.2.1, 00:00:03, Serial0/0/0
S 172.16.10.0/24 [150/0] via 10.1.3.1
from R3 via Corp
C 192.168.10.0/24 is directly connected, FastEthernet0/0
C 192.168.20.0/24 is directly connected, FastEthernet0/1
R 192.168.30.0/24 [120/2] via 10.1.3.1, 00:00:03, Serial0/0/1
[120/2] via 10.1.2.1, 00:00:03, Serial0/0/0
R 192.168.40.0/24 [120/2] via 10.1.3.1, 00:00:03, Serial0/0/1
[120/2] via 10.1.2.1, 00:00:03, Serial0/0/0
from R2 via Corp
Verifying Configurations
in addition to
show ip route
we can also use
show ip protocols
and
debug rip ip
Corp#
show ip protocols
Routing Protocol is "rip"
Sending updates every 30 seconds, next due in 11 seconds
Invalid after 180 seconds, hold down 180, flushed after 240
Outgoing update filter list for all interfaces is not set
Incoming update filter list for all interfaces is not set
Redistributing: rip
Default version control: send version 1, receive any version
Interface Send Recv Triggered RIP Key-chain
Vlan1 1 2 1
FastEthernet0/0 1 2 1
Serial0/0/1 1 2 1
Serial0/1/0 1 2 1
Serial0/0/0 1 2 1
Automatic network summarization is in effect
Maximum path: 4
Routing for Networks:
10.0.0.0
Passive Interface(s):
Routing Information Sources:
Gateway Distance Last Update
10.1.5.2 120 00:00:00
10.1.3.2 120 00:00:10
10.1.2.2 120 00:00:10
10.1.4.2 120 00:00:20
Distance: (default is 120)
R3#
debug ip rip
R3#RIP: received v1 update from 10.1.5.1 on FastEthernet0/0
10.1.1.0 in 1 hops
10.1.2.0 in 1 hops
10.1.3.0 in 1 hops
10.1.4.0 in 1 hops
192.168.10.0 in 2 hops
192.168.20.0 in 2 hops
192.168.30.0 in 2 hops
192.168.40.0 in 2 hops
R3#RIP: sending v1 update to 255.255.255.255 via Dot11Radio0/0/0 (172.16.10.1)
RIP: build update entries
network 10.0.0.0 metric 1
network 192.168.10.0 metric 3
network 192.168.20.0 metric 3
network 192.168.30.0 metric 3
network 192.168.40.0 metric 3
RIP: sending v1 update to 255.255.255.255 via FastEthernet0/0 (10.1.5.2)
RIP: build update entries
network 172.16.0.0 metric 1
output loops until manually disabled..............
R3#
undebug all
All possible debugging has been turned off
Note that due to the Split Horizon rule, R3 is not sending all of it's known RIP data to Corp.
It is sending all known RIP data out of the wifi interface (even there though there's no router that way),
but it is ONLY sending data about the wifi network back to Corp; data that Corp doesnt already have
Now lets look at some examples with sample routers..
I got hung up on these two examples because I found the
wording to be a bit confusing. Also there was subnetting involved that I was able to figure out, but threw me at first
First source of confusion- we have two seperate examples, and I was mixing them up.
The examples are:
Use the debug ip rip command to both:
discover a problem
and figure out how RIP was configured on a router from a different sample network
The conclusion regarding 'figuring out how RIP is configured' on this router, is that RIP networks are set as 10.0.0.0 and 172.16.0.0.
We determined that we are not the 'first source' of info on the 192.168.1.0 nertwork, since it is a metric of 2. We are sending out RIP data on that network,
but that RIP data is made availbale to us via another router.
I also got tripped up on the fact that RA is sending out S0/0 which corresponds 10.0.8.1,
and then receiving on the same interface S0/0 from an ip address of 10.0.15.0 on the other side of the link
I was able to determine that these two address are actually on the same subnet. My initial assumption was that the network address for the link is 10.0.0.0.
The problem doesn't give the subnet mask- I guessed it as /20 by using a 16 block since we can see that the third octet seems to move in 8's
if the network starts at 10.0.0.0 and we use /20 with 16 block, we would indeed have a last host address of 10.0.15.254, so 10.0.15.2 would be a valid host.
So there was a twist to this problem which needed subnetting to solve. It wasnt particulary releveant to the subject of RIP, but I was curious why the address on
the other side of that link looked so strange.
The problem also points out that we can determine there are 'at least' two routers participating in RIP here since we are sending RIP data out two interfaces but
only receiving RIP data on one interface. I'm unclear on why its worded this way; we know we are a RIP router- the fact that we are receiving data on one interface
would suggest there is 'at least one more' RIP router out there.
that's it for this example. Back to the original statement-
Use the debug ip rip command to both discover a problem and figure out
how RIP was configured on a router from a different sample network
We just 'figured out how RIP was configured on a router'.. The second example is regarding 'discovering a problem', although it is mentioned first.
The second example will use debug ip rip and show ip route to find a problem with the network
it looks like RIP data for 172.16.20.0 was received on S0/0, and then that interface was bumped out of the routing table entry for that network in favor of a static route.
ok, moving on now to RIP V2
RIP V2
enable it on all four routers
Corp(config)
router rip
Corp(config-router)
version 2
R1(config)
router rip
R1(config-router)
version 2
R2(config)
router rip
R2(config-router)
version 2
R3(config)
router rip
R3(config-router)
version 2
We'll use R1 to compare RIPv1 and RIPv2
RIPv1
R1(config)
debug ip rip
R1#RIP: sending v1 update to 255.255.255.255 via FastEthernet0/0 (192.168.10.1)
RIP: build update entries
network 10.0.0.0 metric 1
network 172.16.0.0 metric 3
network 192.168.20.0 metric 1
network 192.168.30.0 metric 3
network 192.168.40.0 metric 3
RIP: sending v1 update to 255.255.255.255 via FastEthernet0/1 (192.168.20.1)
RIP: build update entries
network 10.0.0.0 metric 1
network 172.16.0.0 metric 3
network 192.168.10.0 metric 1
network 192.168.30.0 metric 3
network 192.168.40.0 metric 3
RIP: sending v1 update to 255.255.255.255 via Serial0/0/0 (10.1.2.2)
RIP: build update entries
network 10.1.3.0 metric 1
network 192.168.10.0 metric 1
network 192.168.20.0 metric 1
RIP: sending v1 update to 255.255.255.255 via Serial0/0/1 (10.1.3.2)
RIP: build update entries
network 10.1.2.0 metric 1
network 192.168.10.0 metric 1
network 192.168.20.0 metric 1
RIPv2
R1(config)
debug ip rip
R1#RIP: sending v2 update to 224.0.0.9 via FastEthernet0/0 (192.168.10.1)
RIP: build update entries
10.0.0.0/8 via 0.0.0.0, metric 1, tag 0
172.16.0.0/16 via 0.0.0.0, metric 3, tag 0
192.168.20.0/24 via 0.0.0.0, metric 1, tag 0
192.168.30.0/24 via 0.0.0.0, metric 3, tag 0
192.168.40.0/24 via 0.0.0.0, metric 3, tag 0
RIP: sending v2 update to 224.0.0.9 via FastEthernet0/1 (192.168.20.1)
RIP: build update entries
10.0.0.0/8 via 0.0.0.0, metric 1, tag 0
172.16.0.0/16 via 0.0.0.0, metric 3, tag 0
192.168.10.0/24 via 0.0.0.0, metric 1, tag 0
192.168.30.0/24 via 0.0.0.0, metric 3, tag 0
192.168.40.0/24 via 0.0.0.0, metric 3, tag 0
RIP: sending v2 update to 224.0.0.9 via Serial0/0/0 (10.1.2.2)
RIP: build update entries
10.1.3.0/24 via 0.0.0.0, metric 1, tag 0
192.168.10.0/24 via 0.0.0.0, metric 1, tag 0
192.168.20.0/24 via 0.0.0.0, metric 1, tag 0
RIP: sending v2 update to 224.0.0.9 via Serial0/0/1 (10.1.3.2)
RIP: build update entries
10.1.2.0/24 via 0.0.0.0, metric 1, tag 0
192.168.10.0/24 via 0.0.0.0, metric 1, tag 0
192.168.20.0/24 via 0.0.0.0, metric 1, tag 0
R1(config)
show ip protocols
Routing Protocol is "rip"
Sending updates every 30 seconds, next due in 13 seconds
Invalid after 180 seconds, hold down 180, flushed after 240
Outgoing update filter list for all interfaces is not set
Incoming update filter list for all interfaces is not set
Redistributing: rip
Default version control: send version 2, receive 2
Interface Send Recv Triggered RIP Key-chain
FastEthernet0/0 2 2
FastEthernet0/1 2 2
Serial0/0/0 2 2
Serial0/0/1 2 2
Automatic network summarization is in effect
Maximum path: 4
Routing for Networks:
10.0.0.0
192.168.10.0
192.168.20.0
Passive Interface(s):
Routing Information Sources:
Gateway Distance Last Update
10.1.3.1 120 00:00:21
10.1.2.1 120 00:00:21
Distance: (default is 120)
final task of this chapter
Enable a default route out to the internet , and advertise via RIP
R3(config)#
interface s0/1/0 (this is only for example, so I am not adding a serial card to R3)
R3(config-if)#
ip addr 172.16.10.5 255.255.255.252
R3(config-if)#
exit
R3(config)#
ip route 0.0.0.0 0.0.0.0 s0/0
R3(config)#
ip default-network 172.16.0.0 tells other routers via RIP that default WAN route is through R3
Chapter 8 Exam Essentials IP Routing
1. Describe the Basic IP routing process
frame changes at each hop, but packet doesnt change EXCEPT that the TTL field in the IP header decrements
2. List the information required by a router to successfully route packets
destination IP address, location of other routers, possible routers to all remote networks,
the best route to each network, how to maintain and maintain routing info
3. Describe how MAC addresses are used during the routing process
a MAC will never pass a router interface. MACs will change between router interfaces
4. View and interpret the routing table of a router
use show ip route to see the table
a "C" indicates directly connected, an "R" indicates RIP provided the route info, "S" means static
5. differentiate the three types of routing
static- manually configured
dynamic- routers automatically share info via protocol
default- a special route is configured for all traffic without a more specific destination network found in the table
6. Compare and contrast static and dynamic routing
static routing creates no routing update traffic which means less overhead on the routers and links- but it must be
configured manually and can't react if links are lost.
dynamic routing creates update traffic, but it can react to outages and choose the best route when multiple routes exist to the same network
7. Configure static routes at the CLI
route [dest network] [mask] [next hop address OR exit interface] [admin distance] [permanent]
Ex:
Corp(config)#
ip route 192.168.10.0 255.255.255.0 10.1.2.2 150
8. Create a default route
ip route 0.0.0.0 0.0.0.0 [ip address OR exit interface]
Ex:
R3(config)#
ip route 0.0.0.0 0.0.0.0 10.1.5.1 (ingress at Corp router- use if R3 cant identify route)
9. Understand administrative distance and its role in the selection of the best route
an integer from 0 (most trusted) to 255 (no traffic will pass via this route).
All routing protocols are assigned an AD but it can be changed at the CLI
10. Differentiate distance-vector, link-state, and hybrid routing protocols
distance vector- based on hop count (RIP)
link-state- multiple factors such as bandwidth and delay
hybrid- uses both
11. List mechanisms used to prevent routing loops in the network
max hop count, split horizon, route poisoning, holddown counters
12. Describe the counts used the operation of RIP
route update timer- (30) interval between routing updates
route invalid timer- (180, update x 3) before a route is determined invalid
holddown timer-(180) time info is supressed when a link is lost
route flush timer- (240) seconds before invalid and removal
13. Configure RIP routing
router rip
network x.x.x.x
the network(s) you want to advertise from your router. It only works if the other router has RIP enabled.
By enabling RIP, you are able to RECEIVE RIP data from other RIP routers.
by specifying a network, you are SENDING RIP data on that network
14. Identify commands used to verify RIP routing
show ip route will provide contents of the routing table with codes (R, C, S)
debug ip rip will show RIP updates being sent and received
15. Describe the differences between RIPv1 and RIPv2
RIPv1 sends a broadcast (255.255.255.255) every 30 seconds and has an AD of 120.
RIPv1 is classful only, does not send any mask info. No authentication between routers.
RIPv2 sends multicasts (224.0.0.9) every 30 seconds and sends mask info, which allows it to support classless networking, RIPv2 also supports
autentication between routers.
Chapter 8 Written Lab 8.0
1. At the appropriate prompt, create a static route to network 172.16.10.0/24 with a next-hop
gateway of 172.16.20.1 and an administrative distance of 150.
Router(config)#
ip route 172.16.10.0 255.255.255.0 172.16.20.1 150
2. When a PC sends a packet to another PC in a remote network, what destination IP address and MAC address will
be in the frame that it sends to it's default gateway?
the gateway interface MAC and the remote PC's IP
3. At the appropriate prompt, create a default route to 172.16.40.1
Router(config)#
ip route 0.0.0.0 0.0.0.0 172.16.40.1
"to" is the wrong word.. we are going TO any route VIA 172.16.40.1
4. If you are using default routing in a classless environment, what command must also be used?
Router(config)#
ip classless
5. On which type of network is a default route most beneficial?
stub
6. At the appropriate prompt, display the routing table on your router
Router#
show ip route
7. When creating a static or default route, you dont have to use the next-hop ip address;
you can instead use the ____________
exit interface
8. True/False: To reach a destination host, you must know the MAC address of the remote host
false, you need the MAC of your router
9. True/False: To reach a destination host, you must know the IP address of the remote host
true
10. At the appropriate prompt, execute the command required on a DCE serial interface that is not required
on a DTE serial interface
Router(config-if)#
clock rate X
11. At the appropriate prompt, enable RIP routing on the interface with the IP address 10.0.0.1/24
Router(config)#
router rip
Router(config-router)#
network 10.0.0.0
RIPv1 is CLASSFUL only... use the classful mask based on the first octet given
12. At the appropriate prompt, prevent a router from propagating IP information out serial 1
Router(config)#
router rip
Router(config-router)#
passive-interface S0/1
can receive RIP data but will not send
13. What routing loop prevention mechanism sends out a maximum hop count as soon as a link fails?
route poisoning
14. What routing loop prevention mechanism suppresses the resending of routing information to an interface
through which it was received?
split horizon
15. At the appropriate prompt display RIP routing updates as they are sent and received on the router
to the console session
Router#
debug ip rip
to turn it off:
Router#
undebug all
Chapter 8 Hands-on Labs
For these labs we will need a network with three routers.
Lab 8.1 Creating Static routes
first set the interfaces, then program the static routes
LabA(config)#
int s0/0/0
LabA(config-if)#
ip addr 172.16.20.1
LabA(config-if)#
int f0/0
LabA(config-if)#
ip addr 172.16.10.1
-----------------------------------------------------------------
LabA(config)#
ip route 172.16.30.0 255.255.255.0 172.16.20.2
LabA(config)#
ip route 172.16.40.0 255.255.255.0 172.16.20.2
LabB(config)#
int s0/0/0
LabB(config-if)#
ip addr 172.16.20.2
LabB(config-if)#
int s0/0/1
LabB(config-if)#
ip addr 172.16.30.1
-----------------------------------------------------------------
LabB(config)#
ip route 172.16.10.0 255.255.255.0 172.16.20.1
LabB(config)#
ip route 172.16.40.0 255.255.255.0 172.16.30.2
LabC(config)#
int s0/0/0
LabC(config-if)#
ip addr 172.16.30.2
LabC(config-if)#
int f0/0
LabC(config-if)#
ip addr 172.16.40.1
-----------------------------------------------------------------
LabC(config)#
ip route 172.16.10.0 255.255.255.0 172.16.30.1
LabC(config)#
ip route 172.16.20.0 255.255.255.0 172.16.30.1
Lab 8.2 RIP Configuration
remove the static routes, enable and configure RIP with the classful network id that covers the routes you want to advertise
LabA(config)#
no ip route 172.16.30.0 255.255.255.0 172.16.20.2
LabA(config)#
no ip route 172.16.40.0 255.255.255.0 172.16.20.2
LabA(config)#
router rip
LabA(config-router)#
network 172.16.0.0
LabA(config-router)#
do show ip route
Gateway of last resort is not set
172.16.0.0/16 is variably subnetted, 5 subnets, 2 masks
C 172.16.10.0/24 is directly connected, FastEthernet0/0
L 172.16.10.1/32 is directly connected, FastEthernet0/0
C 172.16.20.0/24 is directly connected, Serial0/0/0
L 172.16.20.1/32 is directly connected, Serial0/0/0
R 172.16.30.0/24 [120/1] via 172.16.20.2, 00:00:07, Serial0/0/0
from Lab B
LabB(config)#
no ip route 172.16.10.0 255.255.255.0 172.16.20.1
LabB(config)#
no ip route 172.16.40.0 255.255.255.0 172.16.30.2
LabB(config)#
router rip
LabB(config-router)#
network 172.16.0.0
LabB(config-router)#
do show ip route
Gateway of last resort is not set
172.16.0.0/16 is variably subnetted, 5 subnets, 2 masks
R 172.16.10.0/24 [120/1] via 172.16.20.1, 00:00:13, Serial0/0/0
from LabA
C 172.16.20.0/24 is directly connected, Serial0/0/0
L 172.16.20.2/32 is directly connected, Serial0/0/0
C 172.16.30.0/24 is directly connected, Serial0/0/1
L 172.16.30.1/32 is directly connected, Serial0/0/1
LabC(config)#
no ip route 172.16.10.0 255.255.255.0 172.16.30.1
LabC(config)#
no ip route 172.16.20.0 255.255.255.0 172.16.30.1
LabC(config)#
router rip
LabC(config-router)#
network 172.16.0.0
LabC(config-router)#
do show ip route
Gateway of last resort is not set
172.16.0.0/16 is variably subnetted, 3 subnets, 2 masks
R 172.16.20.0/24 [120/1] via 172.16.30.1, 00:00:05, Serial0/0/0
from LabB
C 172.16.30.0/24 is directly connected, Serial0/0/0
L 172.16.30.2/32 is directly connected, Serial0/0/0
Chapter 8 Review Questions
1. The Acme company uses a router named Gateway to connect to its ISP. The address of the ISP router is 206.143.5.2.
Which three commands could be configured on the gateway router to allow internet access to the entire network?
Set a default route:
Gateway(config)#
ip route 0.0.0.0 0.0.0.0 206.143.5.2 next hop IP
Gateway(config)#
ip route 0.0.0.0 0.0.0.0 S/0 exit interface instead of next hop IP
Gateway(config)#
ip default-network 206.143.5.0 next hop IP
2. What command will prevent RIP routing updates from exiting an interface but will sill allow the interface to receive RIP updates?
Router(config-if)#
passive-interface
3. Which two statemnts are true about ip route 172.16.4.0 255.255.255.0 192.168.4.2?
the command establishes a static route
the default admin distance is used (since we didnt give an AD argument)
4. What two destination addresses will be used by HostA to send data to the HTTPS server as shown in the following network?
MAC of RouterA f0/0 interface
IP address of the server
5. Which two statements are true about this output?
RIP: received v1 update from 192.168.40.2 on S0/1
192.168.50.0 in 16 hops (inaccessible)
RIP: sending v1 update to 255.255.255.255 via F0/0 (192.168.30.1)
RIP: build update entries
network 192.168.20.0 metric 1
network 192.168.40.0 metric 1
network 192.168.50.0 metric 16
RIP: sending v1 update to 255.255.255.255 via S0/1 (192.168.40.1)
true:
there are at least two routers exchanging information
192.168.40.2 will be successful
FALSE
there are three interfaces on the router participating in this update
false because we only see two interfaces represented in the output: S0/1(twice) and F0/0
a ping to 192.168.50.1 will be successful
false because that route has a metric of 16; it's unreachable
6. Describe split horizon
will not advertise a route back the the same router it was learned from
7. Which would be true if HostA is trying to communicate to HostB and interface F0/0 of RouterC goes down, as shown in the graphic?
RouterC will send an ICMP 'destination unreachable type' message to inform HostA that HostB is unreachable
8. Which two statements are true regarding classless routing protocols?
VLSM is permitted
RIPv2 supports classless
9. Which two are true regarding distance-vector vs link-state?
Distance vector sends the whole routing table out all active interfaces(even if a router isnt on the other end)at periodic time intervals
Link-state sends updates containing the state of its own links to all routers in the inter-network
10. Which command display RIP routing updates?
debug ip rip
11. What does RIPv2 use to prvent routing loops?
split horizon stops an update from being send on the same interface it was received
holdown timers allow time for a network to become stable in the case of a flapping link
12. A network administrator views the output from the show ip route command. A network that is advertised
by both RIP and EIGRP appears in the routing table flagged an EIGRP route. Why is the RIP route to this network not used in this routing table?
EIGRP has a lower AD.
RIP=120
OSPP=110
IGRP=110
EIGRP=90
13. You type debug ip rip on your router console and see that 172.16.10.0 is being advertised to you with a metric of 16. What does this mean?
it is inaccessible. in RIP if you see a route advertised with a metric of 16, it's inaccessible
14. What metric does RIPv2 use to find the best path to the remote network?
distance aka hop count
15. The Corporate router receives an IP packet with a source IP address of 192.168.214.20 and a destination address of 192.168.22.3. Looking at the output from the Corp router,
what will the router do with this packet?
Corp# show ip route
[cut]
R 192.168.215.0 [120/2] via 192.168.20.2, Serail0/0
R 192.168.115.0 [120/1] via 192.168.20.0, Serial0/0
R 192.168.30.0 [120/1] via 192.168.20.2, Serial0/0
C 192.168.20.0 is directly connected, Serial0/0
C 192.168.214.0 is directly connected, FastEthernet0/0
Since there is no route to that network, the router will discard the packet and send an ICMP destination unreachable message out F0/0 back the the source network
16. If your routing table has a static, a RIP and an EIGRP route to the same network, which route will be used by default?
Static routes have an admin distance of 1 by default. Unless you change it, a static route will always be used over any other
dynamically learned route.
17. You have the following routing table. Which network will NOT be placed in the neighbor routing table?
R 192.168.30.0/24 [120/1] via 192.168.40.1, Serial 0
C 192.168.40.0/24 is directly connected, Serial 0
172.16.0.0/2 is subnetted, 1 subnets
C 172.16.30.0 is directly connected, Loopback0
R 192.168.20.0/24 [120/1] via 192.168.40.1, Serial 0
R 10.0.0.0/8 [120/15] via 192.168.40.1, Serial 0
C 192.168.50.0/24 is directly connected, Ethernet 0
10.0.0.0 cant be placed in neighboring routing table because it is at 15 hops. 16 hops is invalid in RIP
18. Two connected routers are configured only with RIP. What will be the result when a router receives a routing update that contains a
higher-cost path to a network already in it's routing table?
The router will ignore the update because it is higher cost. When a routing update is received, the router first checks the AD and always chooses
the route with the lowest AD.
19.Which is true about route poisoning?
The router sets the metric for a downed link to "infinity".
20. Which is true about RIPv2?
it has all the same timers as RIPv1
------------------------------------------------------------------------------
END CHAPTER 8
54 hours 1-28 thru 2-14-22
original total 143 hours
11.5 hours review 12-23,24,26-22
review total hours 32
book page 428/822
avg 20 min/page (reading and exercises/labs)
Chapter 9 EIGRP and OSPF
pages 427-502, start 2-14-22-M
What is EIGRP?
Note it's not officially on CCNA 200-301 but it is still important to learn
Enhanced IGRP is a classless, enchanced distance vector protocol that uses the concept of an autonomous system to describe
the set of contigous routers that run the same routing protocol and share routing information.
Features:
Support for IP and IPv6 via protocol-dependent modules (seperate routing tables)
Considered classless
Support for summaries and discontiguous networks
Eficient neighbor discovery
communication via RTP- Reliable Transport Protocol
best path selection via Diffusing Updae Algorithm DUAL
Cisco considers EIGRP a "distance-vector" routing protocol
or an "advanced distance-vector" protocol
or a "hybrid" protocol
Configuring EIGRP on our network
------------------------------------------------------------------------------------------------------------------------------------
Corp(config)#
router eigrp ?
<1-65535> Autonomous system number
Corp(config)#
router eigrp 10
R2(config-router)#
network 10.0.0.0
after eigrp on R1- links from Corp to R1 are up
%DUAL-5-NBRCHANGE: IP-EIGRP 10: Neighbor 10.1.3.2 (Serial0/0/1) is up: new adjacency
%DUAL-5-NBRCHANGE: IP-EIGRP 10: Neighbor 10.1.2.2 (Serial0/0/0) is up: new adjacency
after eigrp on R2- link from Corp to R2 is up
%DUAL-5-NBRCHANGE: IP-EIGRP 10: Neighbor 10.1.4.2 (Serial0/1/0) is up: new adjacency
after eigrp on R3- link from Corp to R3 is up
%DUAL-5-NBRCHANGE: IP-EIGRP 10: Neighbor 10.1.5.2 (FastEthernet0/0) is up: new adjacency
------------------------------------------------------------------------------------------------------------------------------------
R1(config)#
router eigrp 10
R1(config-router)#
network 10.0.0.0
after eigrp on R1- link from R1 to Corp is up
%DUAL-5-NBRCHANGE: IP-EIGRP 10: Neighbor 10.1.3.1 (Serial0/0/1) is up: new adjacency
%DUAL-5-NBRCHANGE: IP-EIGRP 10: Neighbor 10.1.2.1 (Serial0/0/0) is up: new adjacency
R1(config-router)#
network 192.168.10.0
R1(config-router)#
network 192.168.20.0
------------------------------------------------------------------------------------------------------------------------------------
R2(config)#
router eigrp 10
R2(config-router)#
network 10.0.0.0
after eigrp on R2- link from R2 to Corp is up
%DUAL-5-NBRCHANGE: IP-EIGRP 10: Neighbor 10.1.4.1 (Serial0/0/0) is up: new adjacency
R1(config-router)#
network 192.168.30.0
R1(config-router)#
network 192.168.40.0
------------------------------------------------------------------------------------------------------------------------------------
R3(config)#
router eigrp 10
R3(config-router)#
network 10.0.0.0
after eigrp on R3- link from R3 to Corp is up
%DUAL-5-NBRCHANGE: IP-EIGRP 10: Neighbor 10.1.5.1 (FastEthernet0/0) is up: new adjacency
R1(config-router)#
network 172.16.0.0
------------------------------------------------------------------------------------------------------------------------------------
Corp#
show ip route
Gateway of last resort is not set
Gateway of last resort is not set
10.0.0.0/8 is variably subnetted, 10 subnets, 2 masks
C 10.1.1.0/24 is directly connected, Vlan1
L 10.1.1.1/32 is directly connected, Vlan1
C 10.1.2.0/24 is directly connected, Serial0/0/0
L 10.1.2.1/32 is directly connected, Serial0/0/0
C 10.1.3.0/24 is directly connected, Serial0/0/1
L 10.1.3.1/32 is directly connected, Serial0/0/1
C 10.1.4.0/24 is directly connected, Serial0/1/0
L 10.1.4.1/32 is directly connected, Serial0/1/0
C 10.1.5.0/24 is directly connected, FastEthernet0/0
L 10.1.5.1/32 is directly connected, FastEthernet0/0
172.16.0.0/16 is variably subnetted, 2 subnets, 2 masks
R 172.16.0.0/16 [120/1] via 10.1.5.2, 00:00:17, FastEthernet0/0
D 172.16.10.0/24 [90/28160] via 10.1.5.2, 00:00:16, FastEthernet0/0
via R3
D 192.168.10.0/24 [90/2172416] via 10.1.2.2, 00:19:13, Serial0/0/0
[90/2172416] via 10.1.3.2, 00:19:13, Serial0/0/1
D 192.168.20.0/24 [90/2172416] via 10.1.3.2, 00:19:05, Serial0/0/1
[90/2172416] via 10.1.2.2, 00:19:05, Serial0/0/0
via R1
D 192.168.30.0/24 [90/2172416] via 10.1.4.2, 00:01:31, Serial0/1/0
D 192.168.40.0/24 [90/2172416] via 10.1.4.2, 00:01:08, Serial0/1/0
via R2
The "D" routes are for DUAL- Diffusing Update Algorithm, indicating they are EIGRP routes.
Note that we have RIP and EIGRP set currently
------------------------------------------------------------------------------------------------------------------------------------
R1#
show ip route
Gateway of last resort is not set
10.0.0.0/8 is variably subnetted, 6 subnets, 2 masks
D 10.0.0.0/8 is a summary, 00:25:28, Null0
D 10.1.1.0/24 [90/27769856] via 10.1.2.1, 00:31:33, Serial0/0/0
[90/27769856] via 10.1.3.1, 00:31:30, Serial0/0/1
via Corp
C 10.1.2.0/24 is directly connected, Serial0/0/0
C 10.1.3.0/24 is directly connected, Serial0/0/1
D 10.1.4.0/24 [90/2681856] via 10.1.2.1, 00:31:33, Serial0/0/0
[90/2681856] via 10.1.3.1, 00:31:30, Serial0/0/1
D 10.1.5.0/24 [90/2172416] via 10.1.2.1, 00:31:33, Serial0/0/0
[90/2172416] via 10.1.3.1, 00:31:30, Serial0/0/1
via Corp
172.16.0.0/16 is variably subnetted, 2 subnets, 2 masks
R 172.16.0.0/16 [120/2] via 10.1.2.1, 00:00:07, Serial0/0/0
[120/2] via 10.1.3.1, 00:00:07, Serial0/0/1
D 172.16.10.0/24 [90/2172416] via 10.1.2.1, 00:06:31, Serial0/0/0
[90/2172416] via 10.1.3.1, 00:06:31, Serial0/0/1
via Corp
C 192.168.10.0/24 is directly connected, FastEthernet0/0
C 192.168.20.0/24 is directly connected, FastEthernet0/1
D 192.168.30.0/24 [90/2684416] via 10.1.3.1, 00:07:46, Serial0/0/1
[90/2684416] via 10.1.2.1, 00:07:46, Serial0/0/0
D 192.168.40.0/24 [90/2684416] via 10.1.2.1, 00:07:23, Serial0/0/0
[90/2684416] via 10.1.3.1, 00:07:23, Serial0/0/1
via Corp
------------------------------------------------------------------------------------------------------------------------------------
R2#
show ip route
Gateway of last resort is not set
10.0.0.0/8 is variably subnetted, 6 subnets, 2 masks
D 10.0.0.0/8 is a summary, 00:13:09, Null0
D 10.1.1.0/24 [90/27769856] via 10.1.4.1, 00:36:53, Serial0/0/0
D 10.1.2.0/24 [90/2681856] via 10.1.4.1, 00:36:53, Serial0/0/0
D 10.1.3.0/24 [90/2681856] via 10.1.4.1, 00:36:53, Serial0/0/0
via Corp
C 10.1.4.0/24 is directly connected, Serial0/0/0
D 10.1.5.0/24 [90/2172416] via 10.1.4.1, 00:36:53, Serial0/0/0
via Corp
172.16.0.0/16 is variably subnetted, 2 subnets, 2 masks
R 172.16.0.0/16 [120/2] via 10.1.4.1, 00:00:23, Serial0/0/0
D 172.16.10.0/24 [90/2172416] via 10.1.4.1, 00:11:54, Serial0/0/0
via Corp
D 192.168.10.0/24 [90/2684416] via 10.1.4.1, 00:30:51, Serial0/0/0
D 192.168.20.0/24 [90/2684416] via 10.1.4.1, 00:30:43, Serial0/0/0
via Corp
C 192.168.30.0/24 is directly connected, FastEthernet0/0
C 192.168.40.0/24 is directly connected, FastEthernet0/1
------------------------------------------------------------------------------------------------------------------------------------
R3#
show ip route
Gateway of last resort is 10.1.5.1 to network 0.0.0.0
10.0.0.0/8 is variably subnetted, 6 subnets, 2 masks
D 10.1.1.0/24 [90/25628160] via 10.1.5.1, 00:37:20, FastEthernet0/0
D 10.1.2.0/24 [90/2172416] via 10.1.5.1, 00:37:15, FastEthernet0/0
D 10.1.3.0/24 [90/2172416] via 10.1.5.1, 00:37:20, FastEthernet0/0
D 10.1.4.0/24 [90/2172416] via 10.1.5.1, 00:37:20, FastEthernet0/0
via Corp
C 10.1.5.0/24 is directly connected, FastEthernet0/0
L 10.1.5.2/32 is directly connected, FastEthernet0/0
172.16.0.0/16 is variably subnetted, 2 subnets, 2 masks
C 172.16.10.0/24 is directly connected, Dot11Radio0/0/0
L 172.16.10.1/32 is directly connected, Dot11Radio0/0/0
D 192.168.10.0/24 [90/2174976] via 10.1.5.1, 00:31:10, FastEthernet0/0
D 192.168.20.0/24 [90/2174976] via 10.1.5.1, 00:31:02, FastEthernet0/0
via Corp and R1
D 192.168.30.0/24 [90/2174976] via 10.1.5.1, 00:13:28, FastEthernet0/0
D 192.168.40.0/24 [90/2174976] via 10.1.5.1, 00:13:05, FastEthernet0/0
via Corp and R2
S* 0.0.0.0/0 [1/0] via 10.1.5.1
------------------------------------------------------------------------------------------------------------------------------------
turn off auto summary on each router
------------------------------------------------------------------------------------------------------------------------------------
Corp(config)#
router eigrp 10
Corp(config-router)#
no auto-summary
------------------------------------------------------------------------------------------------------------------------------------
R1(config)#
router eigrp 10
R1(config-router)#
no auto-summary
------------------------------------------------------------------------------------------------------------------------------------
R2(config)#
router eigrp 10
R2(config-router)#
no auto-summary
------------------------------------------------------------------------------------------------------------------------------------
R3(config)#
router eigrp 10
R3(config-router)#
no auto-summary
------------------------------------------------------------------------------------------------------------------------------------
compare Corp before and after auto summary turned off
------------------------------------------------------------------------------------------------------------------------------------
auto summary on
Corp#
show ip route
Gateway of last resort is not set
10.0.0.0/8 is variably subnetted, 10 subnets, 2 masks
C 10.1.1.0/24 is directly connected, Vlan1
L 10.1.1.1/32 is directly connected, Vlan1
C 10.1.2.0/24 is directly connected, Serial0/0/0
L 10.1.2.1/32 is directly connected, Serial0/0/0
C 10.1.3.0/24 is directly connected, Serial0/0/1
L 10.1.3.1/32 is directly connected, Serial0/0/1
C 10.1.4.0/24 is directly connected, Serial0/1/0
L 10.1.4.1/32 is directly connected, Serial0/1/0
C 10.1.5.0/24 is directly connected, FastEthernet0/0
L 10.1.5.1/32 is directly connected, FastEthernet0/0
172.16.0.0/16 is variably subnetted, 2 subnets, 2 masks
R 172.16.0.0/16 [120/1] via 10.1.5.2, 00:00:17, FastEthernet0/0
D 172.16.10.0/24 [90/28160] via 10.1.5.2, 00:00:16, FastEthernet0/0
via R3
D 192.168.10.0/24 [90/2172416] via 10.1.2.2, 00:19:13, Serial0/0/0
[90/2172416] via 10.1.3.2, 00:19:13, Serial0/0/1
D 192.168.20.0/24 [90/2172416] via 10.1.3.2, 00:19:05, Serial0/0/1
[90/2172416] via 10.1.2.2, 00:19:05, Serial0/0/0
via R1
D 192.168.30.0/24 [90/2172416] via 10.1.4.2, 00:01:31, Serial0/1/0
D 192.168.40.0/24 [90/2172416] via 10.1.4.2, 00:01:08, Serial0/1/0
via R2
auto summary off
Corp#
show ip route
Gateway of last resort is not set
10.0.0.0/8 is variably subnetted, 10 subnets, 2 masks
C 10.1.1.0/24 is directly connected, Vlan1
L 10.1.1.1/32 is directly connected, Vlan1
C 10.1.2.0/24 is directly connected, Serial0/0/0
L 10.1.2.1/32 is directly connected, Serial0/0/0
C 10.1.3.0/24 is directly connected, Serial0/0/1
L 10.1.3.1/32 is directly connected, Serial0/0/1
C 10.1.4.0/24 is directly connected, Serial0/1/0
L 10.1.4.1/32 is directly connected, Serial0/1/0
C 10.1.5.0/24 is directly connected, FastEthernet0/0
L 10.1.5.1/32 is directly connected, FastEthernet0/0
172.16.0.0/16 is variably subnetted, 2 subnets, 2 masks
R 172.16.0.0/16 [120/1] via 10.1.5.2, 00:00:12, FastEthernet0/0
D 172.16.10.0/24 [90/28160] via 10.1.5.2, 00:45:29, FastEthernet0/0
via R3
D 192.168.10.0/24 [90/2172416] via 10.1.2.2, 00:01:08, Serial0/0/0
[90/2172416] via 10.1.3.2, 00:01:08, Serial0/0/1
D 192.168.20.0/24 [90/2172416] via 10.1.2.2, 00:01:08, Serial0/0/0
[90/2172416] via 10.1.3.2, 00:01:08, Serial0/0/1
via R1
D 192.168.30.0/24 [90/2172416] via 10.1.4.2, 00:00:46, Serial0/1/0
D 192.168.40.0/24 [90/2172416] via 10.1.4.2, 00:00:46, Serial0/1/0
via R2
We are still seeing an auto summarized route- 172.16.0.0 coming from R3.
The book discusses enabling EIGRP auto summary on all four routers- nothing is said about disabling it within RIP or turning off RIP.
RIP auto summarizes by default. We cant get rid of this auto summary route while RIP is on.
Moving on...
VERIFYING EIGRP
several commands available to verify and troubleshoot
show ip route
show the entire routing table
show ip route eigrp
show only EIGRP entries in the routing table
show ip eigrp neighbors
show all EIGRP neigbors
show ip eigrp topology
show entries in the EIGRP topology table
show ip protocols
shows routing protocols configuration
debug eigrp packet
shows hello packets sent/received between adjacent routers
debug ip eigrp events
shows EIGRP changes and updates as they occur on your network
lets take a look at the state of our 4 routers. RIP and EIGRP are running on each.
Notice how this command is giving different outputs between the two different IOS versions
IOS 15.1
Corp#
show ip protocols
Routing Protocol is "eigrp 10 "
Outgoing update filter list for all interfaces is not set
Incoming update filter list for all interfaces is not set
Default networks flagged in outgoing updates
Default networks accepted from incoming updates
Redistributing: eigrp 10
EIGRP-IPv4 Protocol for AS(10)
Metric weight K1=1, K2=0, K3=1, K4=0, K5=0
NSF-aware route hold timer is 240
Router-ID: 10.1.1.1
Topology : 0 (base)
Active Timer: 3 min
Distance: internal 90 external 170
Maximum path: 4
Maximum hopcount 100
Maximum metric variance 1
Automatic Summarization: disabled
Automatic address summarization:
Maximum path: 4
Routing for Networks:
10.0.0.0
Routing Information Sources:
Gateway Distance Last Update
10.1.5.2 90 0
10.1.3.2 90 6464
10.1.2.2 90 6795
10.1.4.2 90 7955
Distance: internal 90 external 170
Routing Protocol is "rip"
Sending updates every 30 seconds, next due in 10 seconds
Invalid after 180 seconds, hold down 180, flushed after 240
Outgoing update filter list for all interfaces is not set
Incoming update filter list for all interfaces is not set
Redistributing: rip
Default version control: send version 2, receive 2
Interface Send Recv Triggered RIP Key-chain
Vlan1 2 2
FastEthernet0/0 2 2
Serial0/1/0 2 2
Serial0/0/1 2 2
Serial0/0/0 2 2
Automatic network summarization is in effect
Maximum path: 4
Routing for Networks:
10.0.0.0
Passive Interface(s):
Routing Information Sources:
Gateway Distance Last Update
10.1.5.2 120 00:00:12
10.1.3.2 120 00:00:16
10.1.2.2 120 00:00:16
10.1.4.2 120 00:00:13
Distance: (default is 120)
IOS 12.4
R1#
show ip protocols
Routing Protocol is "eigrp 10 "
Outgoing update filter list for all interfaces is not set
Incoming update filter list for all interfaces is not set
Default networks flagged in outgoing updates
Default networks accepted from incoming updates
EIGRP metric weight K1=1, K2=0, K3=1, K4=0, K5=0
EIGRP maximum hopcount 100
EIGRP maximum metric variance 1
Redistributing: eigrp 10
Automatic network summarization is not in effect
Maximum path: 4
Routing for Networks:
10.0.0.0
192.168.10.0
192.168.20.0
Routing Information Sources:
Gateway Distance Last Update
10.1.3.1 90 6465
10.1.2.1 90 6794
Distance: internal 90 external 170
Routing Protocol is "rip"
Sending updates every 30 seconds, next due in 21 seconds
Invalid after 180 seconds, hold down 180, flushed after 240
Outgoing update filter list for all interfaces is not set
Incoming update filter list for all interfaces is not set
Redistributing: rip
Default version control: send version 2, receive 2
Interface Send Recv Triggered RIP Key-chain
FastEthernet0/0 2 2
FastEthernet0/1 2 2
Serial0/0/0 2 2
Serial0/0/1 2 2
Automatic network summarization is not in effect
Maximum path: 4
Routing for Networks:
10.0.0.0
192.168.10.0
192.168.20.0
Passive Interface(s):
Routing Information Sources:
Gateway Distance Last Update
10.1.3.1 120 00:00:06
10.1.2.1 120 00:00:06
Distance: (default is 120)
IOS 12.4
R2#
show ip protocols
Routing Protocol is "eigrp 10 "
Outgoing update filter list for all interfaces is not set
Incoming update filter list for all interfaces is not set
Default networks flagged in outgoing updates
Default networks accepted from incoming updates
EIGRP metric weight K1=1, K2=0, K3=1, K4=0, K5=0
EIGRP maximum hopcount 100
EIGRP maximum metric variance 1
Redistributing: eigrp 10
Automatic network summarization is not in effect
Maximum path: 4
Routing for Networks:
10.0.0.0
192.168.30.0
192.168.40.0
Routing Information Sources:
Gateway Distance Last Update
10.1.4.1 90 7955
Distance: internal 90 external 170
Routing Protocol is "rip"
Sending updates every 30 seconds, next due in 11 seconds
Invalid after 180 seconds, hold down 180, flushed after 240
Outgoing update filter list for all interfaces is not set
Incoming update filter list for all interfaces is not set
Redistributing: rip
Default version control: send version 2, receive 2
Interface Send Recv Triggered RIP Key-chain
FastEthernet0/0 2 2
FastEthernet0/1 2 2
Serial0/0/0 2 2
Automatic network summarization is in effect
Maximum path: 4
Routing for Networks:
10.0.0.0
192.168.30.0
192.168.40.0
Passive Interface(s):
Routing Information Sources:
Gateway Distance Last Update
10.1.4.1 120 00:00:20
Distance: (default is 120)
IOS 15.1
R3#
show ip protocols
Routing Protocol is "eigrp 10 "
Outgoing update filter list for all interfaces is not set
Incoming update filter list for all interfaces is not set
Default networks flagged in outgoing updates
Default networks accepted from incoming updates
Redistributing: eigrp 10
EIGRP-IPv4 Protocol for AS(10)
Metric weight K1=1, K2=0, K3=1, K4=0, K5=0
NSF-aware route hold timer is 240
Router-ID: 10.1.5.2
Topology : 0 (base)
Active Timer: 3 min
Distance: internal 90 external 170
Maximum path: 4
Maximum hopcount 100
Maximum metric variance 1
Automatic Summarization: disabled
Automatic address summarization:
Maximum path: 4
Routing for Networks:
10.0.0.0
172.16.0.0
Routing Information Sources:
Gateway Distance Last Update
10.1.5.1 90 0
Distance: internal 90 external 170
Routing Protocol is "rip"
Sending updates every 30 seconds, next due in 27 seconds
Invalid after 180 seconds, hold down 180, flushed after 240
Outgoing update filter list for all interfaces is not set
Incoming update filter list for all interfaces is not set
Redistributing: rip
Default version control: send version 2, receive 2
Interface Send Recv Triggered RIP Key-chain
Dot11Radio0/0/0 2 2
FastEthernet0/0 2 2
Automatic network summarization is not in effect
Maximum path: 4
Routing for Networks:
10.0.0.0
172.16.0.0
Passive Interface(s):
Routing Information Sources:
Gateway Distance Last Update
10.1.5.1 120 00:00:02
Distance: (default is 120)
I'm also noticing that we have inconsistent auto-summarization settings- I was having trouble with this earlier. The book discusses
getting rid of the 172.16.0.0 summarized route in the EIGRP settings. I was not able to get rid of it, I think because RIP is still on, and RIP forces auto-summary
Part of the challenge here is that the book is strictly dealing with IOS 12.4
I will now make sure to turn auto summary off for both RIP and EIGRP on each of the four routers.
OK the part I am forgetting is that we are running RIP V2 which does not force auto-summary but runs it optionally, and we must turn it off to avoid auto summarization.
Corp(config)#
router rip
Corp(config-router)#
no auto-summary
Corp(config-router)#
router eigrp 10
Corp(config-router)#
no auto-summary
R1(config)#
router rip
R1(config-router)#
no auto-summary
R1(config-router)#
router eigrp 10
R1(config-router)#
no auto-summary
R1(config)#
router rip
R1(config-router)#
no auto-summary
R1(config-router)#
router eigrp 10
R2(config-router)#
no auto-summary
R3(config)#
router rip
R3(config-router)#
no auto-summary
R3(config-router)#
router eigrp 10
R3(config-router)#
no auto-summary
and lets see how the output looks now. This time I'll do show ip protocols and
show ip route side by side for each router
IOS 15.1
Corp#
show ip protocols
Routing Protocol is "eigrp 10 "
Outgoing update filter list for all interfaces is not set
Incoming update filter list for all interfaces is not set
Default networks flagged in outgoing updates
Default networks accepted from incoming updates
Redistributing: eigrp 10
EIGRP-IPv4 Protocol for AS(10)
Metric weight K1=1, K2=0, K3=1, K4=0, K5=0
NSF-aware route hold timer is 240
Router-ID: 10.1.1.1
Topology : 0 (base)
Active Timer: 3 min
Distance: internal 90 external 170
Maximum path: 4
Maximum hopcount 100
Maximum metric variance 1
Automatic Summarization: disabled
Automatic address summarization:
Maximum path: 4
Routing for Networks:
10.0.0.0
Routing Information Sources:
Gateway Distance Last Update
10.1.5.2 90 0
10.1.3.2 90 6464
10.1.2.2 90 6795
10.1.4.2 90 7955
Distance: internal 90 external 170
Routing Protocol is "rip" doesnt necessarily mean RIPv1
Sending updates every 30 seconds, next due in 3 seconds
Invalid after 180 seconds, hold down 180, flushed after 240
Outgoing update filter list for all interfaces is not set
Incoming update filter list for all interfaces is not set
Redistributing: rip
Default version control: send version 2, receive 2 RIPv2 is specified
Interface Send Recv Triggered RIP Key-chain
Vlan1 2 2
FastEthernet0/0 2 2
Serial0/1/0 2 2
Serial0/0/1 2 2
Serial0/0/0 2 2
Automatic network summarization is not in effect
Maximum path: 4
Routing for Networks:
10.0.0.0
Passive Interface(s):
Routing Information Sources:
Gateway Distance Last Update
10.1.5.2 120 00:00:02
10.1.3.2 120 00:00:21
10.1.2.2 120 00:00:21
10.1.4.2 120 00:00:04
Distance: (default is 120)
IOS 15.1
Corp#
show ip route
Gateway of last resort is not set
10.0.0.0/8 is variably subnetted, 10 subnets, 2 masks
C 10.1.1.0/24 is directly connected, Vlan1
L 10.1.1.1/32 is directly connected, Vlan1
C 10.1.2.0/24 is directly connected, Serial0/0/0
L 10.1.2.1/32 is directly connected, Serial0/0/0
C 10.1.3.0/24 is directly connected, Serial0/0/1
L 10.1.3.1/32 is directly connected, Serial0/0/1
C 10.1.4.0/24 is directly connected, Serial0/1/0
L 10.1.4.1/32 is directly connected, Serial0/1/0
C 10.1.5.0/24 is directly connected, FastEthernet0/0
L 10.1.5.1/32 is directly connected, FastEthernet0/0
172.16.0.0/24 is subnetted, 1 subnets
D 172.16.10.0/24 [90/28160] via 10.1.5.2, 00:57:25, FastEthernet0/0
D 192.168.10.0/24 [90/2172416] via 10.1.3.2, 00:57:20, Serial0/0/1
[90/2172416] via 10.1.2.2, 00:57:20, Serial0/0/0
D 192.168.20.0/24 [90/2172416] via 10.1.3.2, 00:57:20, Serial0/0/1
[90/2172416] via 10.1.2.2, 00:57:20, Serial0/0/0
D 192.168.30.0/24 [90/2172416] via 10.1.4.2, 00:57:19, Serial0/1/0
D 192.168.40.0/24 [90/2172416] via 10.1.4.2, 00:57:19, Serial0/1/0
IOS 12.4
R1#
show ip protocols
Routing Protocol is "eigrp 10 "
Outgoing update filter list for all interfaces is not set
Incoming update filter list for all interfaces is not set
Default networks flagged in outgoing updates
Default networks accepted from incoming updates
EIGRP metric weight K1=1, K2=0, K3=1, K4=0, K5=0
EIGRP maximum hopcount 100
EIGRP maximum metric variance 1
Redistributing: eigrp 10
Automatic network summarization is not in effect
Maximum path: 4
Routing for Networks:
10.0.0.0
192.168.10.0
192.168.20.0
Routing Information Sources:
Gateway Distance Last Update
10.1.3.1 90 6465
10.1.2.1 90 6794
Distance: internal 90 external 170
Routing Protocol is "rip"
Sending updates every 30 seconds, next due in 26 seconds
Invalid after 180 seconds, hold down 180, flushed after 240
Outgoing update filter list for all interfaces is not set
Incoming update filter list for all interfaces is not set
Redistributing: rip
Default version control: send version 2, receive 2
Interface Send Recv Triggered RIP Key-chain
FastEthernet0/0 2 2
FastEthernet0/1 2 2
Serial0/0/0 2 2
Serial0/0/1 2 2
Automatic network summarization is not in effect
Maximum path: 4
Routing for Networks:
10.0.0.0
192.168.10.0
192.168.20.0
Passive Interface(s):
Routing Information Sources:
Gateway Distance Last Update
10.1.3.1 120 00:00:03
10.1.2.1 120 00:00:03
Distance: (default is 120)
IOS 12.4
R1#
show ip route
Gateway of last resort is not set
10.0.0.0/24 is subnetted, 5 subnets
D 10.1.1.0 [90/27769856] via 10.1.3.1, 00:54:47, Serial0/0/1
[90/27769856] via 10.1.2.1, 00:54:47, Serial0/0/0
C 10.1.2.0 is directly connected, Serial0/0/0
C 10.1.3.0 is directly connected, Serial0/0/1
D 10.1.4.0 [90/2681856] via 10.1.3.1, 00:54:47, Serial0/0/1
[90/2681856] via 10.1.2.1, 00:54:47, Serial0/0/0
D 10.1.5.0 [90/2172416] via 10.1.3.1, 00:54:47, Serial0/0/1
[90/2172416] via 10.1.2.1, 00:54:47, Serial0/0/0
172.16.0.0/24 is subnetted, 1 subnets
D 172.16.10.0 [90/2172416] via 10.1.3.1, 00:54:47, Serial0/0/1
[90/2172416] via 10.1.2.1, 00:54:47, Serial0/0/0
C 192.168.10.0/24 is directly connected, FastEthernet0/0
C 192.168.20.0/24 is directly connected, FastEthernet0/1
D 192.168.30.0/24 [90/2684416] via 10.1.3.1, 00:54:46, Serial0/0/1
[90/2684416] via 10.1.2.1, 00:54:46, Serial0/0/0
D 192.168.40.0/24 [90/2684416] via 10.1.3.1, 00:54:46, Serial0/0/1
[90/2684416] via 10.1.2.1, 00:54:46, Serial0/0/0
note that the DUAL routes being advertised from the 10.0.0.0 networks are all specific to the third octet.. that's because we are reading those routes
from their source, aka the router which they are directly connected to, Corp.
and on Corp, those networks were added to the interfaces with a /24 mask.
so even though our EIGRP config doesnt specifically include /24 networks.. we told it to include anything with a 10.x.x.x
Corp is advertising to R1 our /24 network interfaces that have a 10 in the first octet, EXCEPT the two which are directly connected to R1
10.1.1.0
10.1.4.0
10.1.5.0
are assumed to be the subnets based on the info we configured, which was 10.1.4.1/24 on corp, and 10.1.4.2/24 on r2 s0/0/0
nowhere in this configuration, have we entered the 10.1.4.0 network.
EIGRP is figuring it out based on the /24 mask we gave when assiging he IPs to the interfaces
IOS 12.4
R2#
show ip protocols
Routing Protocol is "eigrp 10 "
Outgoing update filter list for all interfaces is not set
Incoming update filter list for all interfaces is not set
Default networks flagged in outgoing updates
Default networks accepted from incoming updates
EIGRP metric weight K1=1, K2=0, K3=1, K4=0, K5=0
EIGRP maximum hopcount 100
EIGRP maximum metric variance 1
Redistributing: eigrp 10
Automatic network summarization is not in effect
Maximum path: 4
Routing for Networks:
10.0.0.0
192.168.30.0
192.168.40.0
Routing Information Sources:
Gateway Distance Last Update
10.1.4.1 90 7955
Distance: internal 90 external 170
Routing Protocol is "rip"
Sending updates every 30 seconds, next due in 18 seconds
Invalid after 180 seconds, hold down 180, flushed after 240
Outgoing update filter list for all interfaces is not set
Incoming update filter list for all interfaces is not set
Redistributing: rip
Default version control: send version 2, receive 2
Interface Send Recv Triggered RIP Key-chain
FastEthernet0/0 2 2
FastEthernet0/1 2 2
Serial0/0/0 2 2
Automatic network summarization is not in effect
Maximum path: 4
Routing for Networks:
10.0.0.0
192.168.30.0
192.168.40.0
Passive Interface(s):
Routing Information Sources:
Gateway Distance Last Update
10.1.4.1 120 00:00:07
Distance: (default is 120)
IOS 12.4
R2#
show ip route
Gateway of last resort is not set
10.0.0.0/24 is subnetted, 5 subnets
D 10.1.1.0 [90/27769856] via 10.1.4.1, 00:59:10, Serial0/0/0
D 10.1.2.0 [90/2681856] via 10.1.4.1, 00:59:10, Serial0/0/0
D 10.1.3.0 [90/2681856] via 10.1.4.1, 00:59:10, Serial0/0/0
C 10.1.4.0 is directly connected, Serial0/0/0
D 10.1.5.0 [90/2172416] via 10.1.4.1, 00:59:10, Serial0/0/0
172.16.0.0/24 is subnetted, 1 subnets
D 172.16.10.0 [90/2172416] via 10.1.4.1, 00:59:10, Serial0/0/0
D 192.168.10.0/24 [90/2684416] via 10.1.4.1, 00:59:10, Serial0/0/0
D 192.168.20.0/24 [90/2684416] via 10.1.4.1, 00:59:10, Serial0/0/0
C 192.168.30.0/24 is directly connected, FastEthernet0/0
C 192.168.40.0/24 is directly connected, FastEthernet0/1
IOS 15.1
R3#
show ip protocols
Routing Protocol is "eigrp 10 "
Outgoing update filter list for all interfaces is not set
Incoming update filter list for all interfaces is not set
Default networks flagged in outgoing updates
Default networks accepted from incoming updates
Redistributing: eigrp 10
EIGRP-IPv4 Protocol for AS(10)
Metric weight K1=1, K2=0, K3=1, K4=0, K5=0
NSF-aware route hold timer is 240
Router-ID: 10.1.5.2
Topology : 0 (base)
Active Timer: 3 min
Distance: internal 90 external 170
Maximum path: 4
Maximum hopcount 100
Maximum metric variance 1
Automatic Summarization: disabled
Automatic address summarization:
Maximum path: 4
Routing for Networks:
10.0.0.0
172.16.0.0
Routing Information Sources:
Gateway Distance Last Update
10.1.5.1 90 0
Distance: internal 90 external 170
Routing Protocol is "rip"
Sending updates every 30 seconds, next due in 15 seconds
Invalid after 180 seconds, hold down 180, flushed after 240
Outgoing update filter list for all interfaces is not set
Incoming update filter list for all interfaces is not set
Redistributing: rip
Default version control: send version 2, receive 2
Interface Send Recv Triggered RIP Key-chain
Dot11Radio0/0/0 2 2
FastEthernet0/0 2 2
Automatic network summarization is not in effect
Maximum path: 4
Routing for Networks:
10.0.0.0
172.16.0.0
Passive Interface(s):
Routing Information Sources:
Gateway Distance Last Update
10.1.5.1 120 00:00:14
Distance: (default is 120)
IOS 15.1
R3#
show ip route
Gateway of last resort is 10.1.5.1 to network 0.0.0.0
10.0.0.0/8 is variably subnetted, 6 subnets, 2 masks
D 10.1.1.0/24 [90/25628160] via 10.1.5.1, 00:59:52, FastEthernet0/0
D 10.1.2.0/24 [90/2172416] via 10.1.5.1, 00:59:47, FastEthernet0/0
D 10.1.3.0/24 [90/2172416] via 10.1.5.1, 00:59:52, FastEthernet0/0
D 10.1.4.0/24 [90/2172416] via 10.1.5.1, 00:59:52, FastEthernet0/0
C 10.1.5.0/24 is directly connected, FastEthernet0/0
L 10.1.5.2/32 is directly connected, FastEthernet0/0
172.16.0.0/16 is variably subnetted, 2 subnets, 2 masks
C 172.16.10.0/24 is directly connected, Dot11Radio0/0/0
L 172.16.10.1/32 is directly connected, Dot11Radio0/0/0
D 192.168.10.0/24 [90/2174976] via 10.1.5.1, 00:59:47, FastEthernet0/0
D 192.168.20.0/24 [90/2174976] via 10.1.5.1, 00:59:47, FastEthernet0/0
D 192.168.30.0/24 [90/2174976] via 10.1.5.1, 00:59:46, FastEthernet0/0
D 192.168.40.0/24 [90/2174976] via 10.1.5.1, 00:59:46, FastEthernet0/0
S* 0.0.0.0/0 [1/0] via 10.1.5.1
Observations:
Since this is a 15.1 router, we always get a "L" local route when
we have a "C" connected route. In R3's case, the 172.16.10.0 network
is directly connected. The interface which connects it, 172.16.10.1,
counts as a "local" route. This is NOT the case on the 12.4 routers.
looking to the left, our protocol output tells us two key facts for both EIGRP and RIP:
Routing for networks:
10.0.0.0
172.16.0.0
R3 is responsible for *sending* data about these two networks to our other EIGRP routers...
"I'm R3 and I can connect you to networks on the R3
router or networks on the Corp router"
Notice how the 192 networks arent listed. R3 isnt connected to a 192 network directly, nor is it connected to a neighbor who is directly connected.
If I, as a client, am sending data to a 192 network from the 172 network, I will start
at R3. Since R3 is receiving routes for the 192 networks via Corp, I will be able to reach a 192 network via Corp.
My connection to corp will happen VIA a "10.0.0.0" route.
R3 is technically only routing for 172 and 10 networks. Beyond that, it could potentially connect to many other different networks. But in terms of the R3 routing table,
all it can offer is a path out to the 172 network or the 10 network
Routing information sources:
10.1.5.1
In this case I can see that R3 is receiving routing data from one interface only,
and that is it's link to Corp. Some of the data we are receiving from Corp actually originates
at other routers, but we cant see that here; the data comes to us from Corp, and that is all we know
EIGRP TERMINOLOGY
FEASIBLE DISTANCE (FD)
the best metric among all paths, including to the next hop neighbor. You will only see the route with the lowest FD appear in the routing table
The FD is calculated by adding the reported distance from the neighbor (AD) plus the metric to that neighbor
ADVERTISED DISTANCE (AD)
the metric of a remote network as reported by a neighbor, listed second in parenthesis in toplogy table
P 192.168.20.0/24, 2 successors, FD is 2172416
via 10.1.3.2 (2172416/28160), Serial0/0/1
feasible / advertised
Neighbor Table
each router keeps state information about adjacent neighbors.. When a new neighbor is learned, the address and interface are recorded.
The neighbor table is stored in RAM.
Sequence numbres are used to match acks with update packets. The last squence number received from a neighbor is recorded so out of order packets
can be detected
Topology Table
acted upon by DUAL Diffusing Update Alogorithm. Contains all destinations advertised by neighboring routers.
For each neighbor, the adversited distance, which comes only from that neighbor's routing table, is recorded
The feasible distance is also recorded.
Feasible Successor
a PATH whose advertised distance is less than the feasible distance of the current succesor, and is considered a backup route.
EIGRP keeps up to 16 feasible successors in the toplogy table.
The one with the best metric (The Successor) is copied and placed into the routing table
Successor
the best route to a remote network, used by EIGRP to forward traffic. It's backed up by a feasible successor, if one is available.
lets demo some more of the commands
VERIFYING EIGRP
several commands available to verify and troubleshoot
show ip route
show the entire routing table
show ip route eigrp
show only EIGRP entries in the routing table
show ip eigrp neighbors
show all EIGRP neigbors
show ip eigrp topology
show entries in the EIGRP topology table
show ip protocols
shows routing protocols configuration
debug eigrp packet
shows hello packets sent/received between adjacent routers
debug ip eigrp events
shows EIGRP changes and updates as they occur on your network
Corp#
show ip eigrp ?
interfaces IP-EIGRP interfaces
neighbors IP-EIGRP neighbors
topology IP-EIGRP Topology Table
traffic IP-EIGRP Traffic Statistics
Corp#
show ip eigrp topology
IP-EIGRP Topology Table for AS 10/ID(10.1.5.1)
Codes: P - Passive, A - Active, U - Update, Q - Query, R - Reply,
r - Reply status
P 10.1.1.0/24, 1 successors, FD is 25625600
via Connected, Vlan1
P 10.1.2.0/24, 1 successors, FD is 2169856
via Connected, Serial0/0/0
P 10.1.3.0/24, 1 successors, FD is 2169856
via Connected, Serial0/0/1
P 10.1.4.0/24, 1 successors, FD is 2169856
via Connected, Serial0/1/0
P 10.1.5.0/24, 1 successors, FD is 28160
via Connected, FastEthernet0/0
P 172.16.10.0/24, 1 successors, FD is 28160
via 10.1.5.2 (28160/25600), FastEthernet0/0
P 192.168.10.0/24, 2 successors, FD is 2172416
via 10.1.3.2 (2172416/28160), Serial0/0/1
via 10.1.2.2 (2172416/28160), Serial0/0/0
P 192.168.20.0/24, 2 successors, FD is 2172416
via 10.1.3.2 (2172416/28160), Serial0/0/1
via 10.1.2.2 (2172416/28160), Serial0/0/0
P 192.168.30.0/24, 1 successors, FD is 2172416
via 10.1.4.2 (2172416/28160), Serial0/1/0
P 192.168.40.0/24, 1 successors, FD is 2172416
via 10.1.4.2 (2172416/28160), Serial0/1/0
the "P" preceding each entry is for PASSIVE
these routes are in a passive state, which is good
if they move to an ACTIVE state, it means the have lost their path in the network and looking for a replacement.
Each entry also shows the FEASIBLE DISTANCE, the next hop address, and the local egress interface
Corp#
show ip eigrp neighbors
IP-EIGRP neighbors for process 10
H Address Interface Hold Uptime SRTT RTO Q Seq
(sec) (ms) Cnt Num
0 10.1.5.2 Fa0/0 14 02:00:05 40 1000 0 19
1 10.1.3.2 Se0/0/1 13 01:59:59 40 1000 0 14
2 10.1.2.2 Se0/0/0 13 01:59:59 40 1000 0 13
3 10.1.4.2 Se0/1/0 12 01:59:57 40 1000 0 15
fields:
H - the order in which the neighbors were discovered
hold - how long the router will wait for a hello packet
uptime - how long the neigborship has been established
SRTT - smooth round trip timer - the time it takes for a round trip from this router, to neighbor, and back.
SRTT is used to determine how long to wait for a MULTICAST reply.
if a reply isnt received in time, the router switches to UNICASTS
RTO - Retransmission Time Out- is the time EIGRP waits before retransmitting a packet from the retransmission queue
Q - indicates wheter there are oustanding messages in the queue
Seq - indicates the sequence number of the last update from that neighbor. This is used to maintain syncrhonization and avoid duplicate
or out-of-sequence processing of messages
Corp#
show ip route eigrp
172.16.0.0/24 is subnetted, 1 subnets
D 172.16.10.0 [90/28160] via 10.1.5.2, 02:08:04, FastEthernet0/0
D 192.168.10.0/24 [90/2172416] via 10.1.3.2, 02:07:59, Serial0/0/1
[90/2172416] via 10.1.2.2, 02:07:59, Serial0/0/0
D 192.168.20.0/24 [90/2172416] via 10.1.3.2, 02:07:59, Serial0/0/1
[90/2172416] via 10.1.2.2, 02:07:59, Serial0/0/0
D 192.168.30.0/24 [90/2172416] via 10.1.4.2, 02:07:58, Serial0/1/0
D 192.168.40.0/24 [90/2172416] via 10.1.4.2, 02:07:58, Serial0/1/0
Corp#
show ip eigrp interfaces
IP-EIGRP interfaces for process 10
Xmit Queue Mean Pacing Time Multicast Pending
Interface Peers Un/Reliable SRTT Un/Reliable Flow Timer Routes
Vlan 0 0/0 1236 0/10 0 0
Fa0/0 1 0/0 1236 0/10 0 0
Se0/1/0 1 0/0 1236 0/10 0 0
Se0/0/1 1 0/0 1236 0/10 0 0
Se0/0/0 1 0/0 1236 0/10 0 0
Corp#
show ip protocols
Routing Protocol is "eigrp 10 "
Outgoing update filter list for all interfaces is not set
Incoming update filter list for all interfaces is not set
Default networks flagged in outgoing updates
Default networks accepted from incoming updates
Redistributing: eigrp 10
EIGRP-IPv4 Protocol for AS(10)
Metric weight K1=1, K2=0, K3=1, K4=0, K5=0 using K1 bandwidth and K2 delay by default
NSF-aware route hold timer is 240
Router-ID: 10.1.1.1
Topology : 0 (base)
Active Timer: 3 min
Distance: internal 90 external 170
Maximum path: 4
Maximum hopcount 100
Maximum metric variance 1
Automatic Summarization: disabled
Automatic address summarization:
Maximum path: 4
Routing for Networks:
10.0.0.0
Routing Information Sources:
Gateway Distance Last Update
10.1.5.2 90 0
10.1.3.2 90 8936
10.1.4.2 90 9511
10.1.2.2 90 9597
Distance: internal 90 external 170
Routing Protocol is "rip"
Sending updates every 30 seconds, next due in 13 seconds
Invalid after 180 seconds, hold down 180, flushed after 240
Outgoing update filter list for all interfaces is not set
Incoming update filter list for all interfaces is not set
Redistributing: rip
Default version control: send version 2, receive 2
Interface Send Recv Triggered RIP Key-chain
Vlan1 2 2
FastEthernet0/0 2 2
Serial0/0/1 2 2
Serial0/1/0 2 2
Serial0/0/0 2 2
Automatic network summarization is not in effect
Maximum path: 4
Routing for Networks:
10.0.0.0
Passive Interface(s):
Routing Information Sources:
Gateway Distance Last Update
10.1.5.2 120 00:00:05
10.1.3.2 120 00:00:12
10.1.2.2 120 00:00:12
10.1.4.2 120 00:00:17
Distance: (default is 120)
corp#
debug eigrp packet
break into two columns for readability
Observations:
There doesnt appear to be a pattern in the order each router is addressed, except that the TO's and FROM"s are grouped together
The TO messages dont show the destination IP, only the egress local interface
The FROM messages do show the remote IP, as well as the local ingress interface
Corp#
EIGRP: Received HELLO on FastEthernet0/0 nbr 10.1.5.2
AS 10, Flags 0x0, Seq 18/0 idbQ 0/0
hello from R3
Corp#
EIGRP: Received HELLO on Serial0/1/0 nbr 10.1.4.2
AS 10, Flags 0x0, Seq 16/0 idbQ 0/0
hello from R2
Corp#
EIGRP: Received HELLO on Serial0/0/0 nbr 10.1.2.2
AS 10, Flags 0x0, Seq 19/0 idbQ 0/0
hello from R1
------------------------------------------------------------
Corp#
EIGRP: Sending HELLO on Serial0/1/0
AS 10, Flags 0x0, Seq 21/0 idbQ 0/0 iidbQ un/rely 0/0
hello to R2
Corp#
EIGRP: Sending HELLO on FastEthernet0/0
AS 10, Flags 0x0, Seq 21/0 idbQ 0/0 iidbQ un/rely 0/0
hello to R3
Corp#
EIGRP: Sending HELLO on Serial0/0/1
AS 10, Flags 0x0, Seq 21/0 idbQ 0/0 iidbQ un/rely 0/0
hello to R1
Corp#
EIGRP: Sending HELLO on Serial0/0/0
AS 10, Flags 0x0, Seq 21/0 idbQ 0/0 iidbQ un/rely 0/0
hello to R1
Corp#
EIGRP: Sending HELLO on Vlan1
AS 10, Flags 0x0, Seq 21/0 idbQ 0/0 iidbQ un/rely 0/0
hello to switch card (not a router....)
------------------------------------------------------------
Corp#
EIGRP: Received HELLO on Serial0/0/1 nbr 10.1.3.2
AS 10, Flags 0x0, Seq 19/0 idbQ 0/0
hello from R1
Corp#
EIGRP: Received HELLO on FastEthernet0/0 nbr 10.1.5.2
AS 10, Flags 0x0, Seq 18/0 idbQ 0/0
hello from R3
Corp#
EIGRP: Received HELLO on Serial0/0/0 nbr 10.1.2.2
AS 10, Flags 0x0, Seq 19/0 idbQ 0/0
hello from R1
Corp#
EIGRP: Received HELLO on Serial0/1/0 nbr 10.1.4.2
AS 10, Flags 0x0, Seq 16/0 idbQ 0/0
hello from R2
------------------------------------------------------------
Corp#
EIGRP: Sending HELLO on Serial0/1/0
AS 10, Flags 0x0, Seq 21/0 idbQ 0/0 iidbQ un/rely 0/0
hello to R2... no neighbor IP?
Corp#
EIGRP: Sending HELLO on Serial0/0/0
AS 10, Flags 0x0, Seq 21/0 idbQ 0/0 iidbQ un/rely 0/0
hello to R1... no neighbor IP?
Corp#
EIGRP: Sending HELLO on FastEthernet0/0
AS 10, Flags 0x0, Seq 21/0 idbQ 0/0 iidbQ un/rely 0/0
hello to R3... no neighbor IP?
Corp#
EIGRP: Sending HELLO on Serial0/0/1
AS 10, Flags 0x0, Seq 21/0 idbQ 0/0 iidbQ un/rely 0/0
hello to R1
Corp#
EIGRP: Sending HELLO on Vlan1
AS 10, Flags 0x0, Seq 21/0 idbQ 0/0 iidbQ un/rely 0/0
hello to switch card (not a router)
------------------------------------------------------------
OUTPUT CONTINUES IN NEXT COLUMN
Corp#
EIGRP: Received HELLO on Serial0/0/1 nbr 10.1.3.2
AS 10, Flags 0x0, Seq 19/0 idbQ 0/0
hello from R1
Corp#
EIGRP: Received HELLO on FastEthernet0/0 nbr 10.1.5.2
AS 10, Flags 0x0, Seq 18/0 idbQ 0/0
hello from R3
Corp#
EIGRP: Received HELLO on Serial0/0/0 nbr 10.1.2.2
AS 10, Flags 0x0, Seq 19/0 idbQ 0/0
hello from R1
Corp#
EIGRP: Received HELLO on Serial0/1/0 nbr 10.1.4.2
AS 10, Flags 0x0, Seq 16/0 idbQ 0/0
hello from R2
------------------------------------------------------------
Corp#
EIGRP: Sending HELLO on Serial0/1/0
AS 10, Flags 0x0, Seq 21/0 idbQ 0/0 iidbQ un/rely 0/0
hello to R2
Corp#
EIGRP: Sending HELLO on Serial0/0/0
AS 10, Flags 0x0, Seq 21/0 idbQ 0/0 iidbQ un/rely 0/0
hello to R1
Corp#
EIGRP: Sending HELLO on Vlan1
AS 10, Flags 0x0, Seq 21/0 idbQ 0/0 iidbQ un/rely 0/0
hello to Corp switchcard
Corp#
EIGRP: Sending HELLO on Serial0/0/1
AS 10, Flags 0x0, Seq 21/0 idbQ 0/0 iidbQ un/rely 0/0
hello to R1
Corp#
EIGRP: Sending HELLO on FastEthernet0/0
AS 10, Flags 0x0, Seq 21/0 idbQ 0/0 iidbQ un/rely 0/0
hello to R3... no neighbor IP?
------------------------------------------------------------
Corp#
EIGRP: Received HELLO on Serial0/0/1 nbr 10.1.3.2
AS 10, Flags 0x0, Seq 19/0 idbQ 0/0
hello from R1
Corp#
EIGRP: Received HELLO on FastEthernet0/0 nbr 10.1.5.2
AS 10, Flags 0x0, Seq 18/0 idbQ 0/0
hello from R3
Corp#
EIGRP: Received HELLO on Serial0/1/0 nbr 10.1.4.2
AS 10, Flags 0x0, Seq 16/0 idbQ 0/0
hello from R2
Corp#
EIGRP: Received HELLO on Serial0/0/0 nbr 10.1.2.2
AS 10, Flags 0x0, Seq 19/0 idbQ 0/0
hello from R1
------------------------------------------------------------
Corp#
EIGRP: Sending HELLO on Serial0/1/0
AS 10, Flags 0x0, Seq 21/0 idbQ 0/0 iidbQ un/rely 0/0
hello to R2
Corp#
EIGRP: Sending HELLO on Vlan1
AS 10, Flags 0x0, Seq 21/0 idbQ 0/0 iidbQ un/rely 0/0
hello to Corp switchcard
EIGRP: Sending HELLO on Serial0/0/0
AS 10, Flags 0x0, Seq 21/0 idbQ 0/0 iidbQ un/rely 0/0
hello to R1
EIGRP: Sending HELLO on Serial0/0/1
AS 10, Flags 0x0, Seq 21/0 idbQ 0/0 iidbQ un/rely 0/0
hello to R1
Corp#
EIGRP: Sending HELLO on FastEthernet0/0
AS 10, Flags 0x0, Seq 21/0 idbQ 0/0 iidbQ un/rely 0/0
hello to R3
------------------------------------------------------------
Now some videos. To reinforce EIGRP concepts, and lead into OSPF
OSPF - OPEN SHORTEST PATH FIRST
Before enabling OSPF, we'll turn off RIP and EIGRP on all four routers.
Device(config)#
no router eigrp 10
Device(config)#
no router rip
The OSPF configs for the local egress ip address
Corp(config)#
router ospf 132
Corp(config)#
network 10.1.0.0 0.0.255.255 area 0
R1(config)#
router ospf 1
R1(config)#
network 10.1.0.0 0.0.255.255 area 0
R1(config)#
network 192.168.0.0 0.0.255.255 area 0
R2(config)#
router ospf 45678
R2(config)#
network 10.0.0.0 0.0.0.255 area 0
R2(config)#
network 192.168.30.1 0.0.0.0 area 0
R2(config)#
network 192.168.40.1 0.0.0.0 area 0
all 32 bits of the mask are specified for the 192 entries;
these are not network id's, they are HOST id's of the specific interfaces, which are EGRESS interfaces on the router we are configuring
R3(config)#
router ospf 1
R2(config)#
network 10.1.5.2 0.0.0.255 area 0
R2(config)#
network 172.16.10.0 0.0.0.255 area 0
Wildcard Masks
these notes are not intended to be a precise explanation of wlidcard masking, but rather a look into my thought process as I am learning the concept.
resources:
traceroute blog examples
routerjockey blog examples
subnetonline wildcard calculator
Ch 9 Exam Essentials
1. Know EIGRP features
classless (like RipV2 and OSPF)
distance vector
supports IP, IPX, appleTalk, IPV6
supports summaries and discontiguous networks
uses the Diffusing Update Algorithm (DUAL) to maintain route information
uses RTP to communicate with other EIGRP routers
uses the concept of an autonomous system to describe the set of contiguous routers that run the same routing protocol and share routing information
considered CLASSLESS- includes the subnet mask in its route updates
sends traditional distance-vector updates containing info about networks plus the cost of reaching them from the perspective of the advertising router
but not strictly distance-vector. Has link-state characteristics: synchronizes routing tables between neighbors at startup and then sends specific updates only when topology changes.
max hop count of 255 (default is 100)
but hop count is NOT a metric, like in RIP. Hop count is how many routers an EIGRP route update can traverse before being discarded. This limits the size of the AS.
2. Know how to configure EIGRP
the router eigrp [as] command turns EIGRP routing on in the router. Unlike RIPv1, EIGRP uses classless routing. BUT you can still configure as classful.
R1(config)#
router eigrp 10
enters router config mode
R1(config-router)#
network 10.0.0.0
on this router, interfaces that fall within 10.0.0.0 will advertise EIGRP info
3. Know how to verify EIGRP operation
Corp#
show ip
protocols
Corp#
show ip
route
Corp#
show ip
route eigrp
Corp#
show ip
eigrp neighbors
Corp#
show ip
eigrp topology
Corp#
show ip
eigrp interfaces
Corp#
show ip
protocols
info about all active routing protocols
Routing Protocol is "eigrp 10 "
Outgoing update filter list for all interfaces is not set
Incoming update filter list for all interfaces is not set
Default networks flagged in outgoing updates
Default networks accepted from incoming updates
Redistributing: eigrp 10
EIGRP-IPv4 Protocol for AS(10)
Metric weight K1=1, K2=0, K3=1, K4=0, K5=0
NSF-aware route hold timer is 240
Router-ID: 10.1.1.1
Topology : 0 (base)
Active Timer: 3 min
Distance: internal 90 external 170
Maximum path: 4
Maximum hopcount 100
Maximum metric variance 1
Automatic Summarization: disabled
Automatic address summarization:
Maximum path: 4
Routing for Networks:
10.0.0.0
Routing Information Sources:
Gateway Distance Last Update
10.1.2.2 90 200105
10.1.3.2 90 200113
10.1.4.2 90 254351
10.1.5.2 90 303742
Distance: internal 90 external 170
Corp#
show ip
protocols
(continued)
Routing Protocol is "rip"
Sending updates every 30 seconds, next due in 6 seconds
Invalid after 180 seconds, hold down 180, flushed after 240
Outgoing update filter list for all interfaces is not set
Incoming update filter list for all interfaces is not set
Redistributing: rip
Default version control: send version 2, receive 2
Interface Send Recv Triggered RIP Key-chain
Vlan1 2 2
FastEthernet0/0 2 2
Serial0/1/0 2 2
Serial0/0/1 2 2
Serial0/0/0 2 2
Automatic network summarization is not in effect
Maximum path: 4
Routing for Networks:
10.0.0.0
Passive Interface(s):
Routing Information Sources:
Gateway Distance Last Update
10.1.5.2 120 00:00:15
10.1.3.2 120 00:00:01
10.1.2.2 120 00:00:01
10.1.4.2 120 00:00:17
Distance: (default is 120)
Corp#
show ip
route
entire routing table
Codes: L - local, C - connected, S - static, R - RIP, M - mobile, B - BGP
D - EIGRP, EX - EIGRP external, O - OSPF, IA - OSPF inter area
N1 - OSPF NSSA external type 1, N2 - OSPF NSSA external type 2
E1 - OSPF external type 1, E2 - OSPF external type 2, E - EGP
i - IS-IS, L1 - IS-IS level-1, L2 - IS-IS level-2, ia - IS-IS inter area
* - candidate default, U - per-user static route, o - ODR
P - periodic downloaded static route
Gateway of last resort is not set
10.0.0.0/8 is variably subnetted, 10 subnets, 2 masks
C 10.1.1.0/24 is directly connected, Vlan1
L 10.1.1.1/32 is directly connected, Vlan1
C 10.1.2.0/24 is directly connected, Serial0/0/0
L 10.1.2.1/32 is directly connected, Serial0/0/0
C 10.1.3.0/24 is directly connected, Serial0/0/1
L 10.1.3.1/32 is directly connected, Serial0/0/1
C 10.1.4.0/24 is directly connected, Serial0/1/0
L 10.1.4.1/32 is directly connected, Serial0/1/0
C 10.1.5.0/24 is directly connected, FastEthernet0/0
L 10.1.5.1/32 is directly connected, FastEthernet0/0
172.16.0.0/16 is variably subnetted, 2 subnets, 2 masks
R 172.16.0.0/16 [120/1] via 10.1.5.2, 00:00:14, FastEthernet0/0
D 172.16.10.0/24 [90/28160] via 10.1.5.2, 00:07:23, FastEthernet0/0
D 192.168.10.0/24 [90/2172416] via 10.1.3.2, 00:09:13, Serial0/0/1
[90/2172416] via 10.1.2.2, 00:09:13, Serial0/0/0
D 192.168.20.0/24 [90/2172416] via 10.1.3.2, 00:09:13, Serial0/0/1
[90/2172416] via 10.1.2.2, 00:09:13, Serial0/0/0
D 192.168.30.0/24 [90/2172416] via 10.1.4.2, 00:08:59, Serial0/1/0
D 192.168.40.0/24 [90/2172416] via 10.1.4.2, 00:08:59, Serial0/1/0
Shows the entire routing table
Corp#
show ip
eigrp toplogy
all nets the Corp router can see, including on the other side of other routers
IP-EIGRP Topology Table for AS 10/ID(10.1.5.1)
Codes: P - Passive, A - Active, U - Update, Q - Query, R - Reply,
r - Reply status
directly connected via local egress interface
P 10.1.1.0/24, 1 successors, FD is 25625600
via Connected, Vlan1
P 10.1.2.0/24, 1 successors, FD is 2169856
via Connected, Serial0/0/0
P 10.1.3.0/24, 1 successors, FD is 2169856
via Connected, Serial0/0/1
P 10.1.4.0/24, 1 successors, FD is 2169856
via Connected, Serial0/1/0
P 10.1.5.0/24, 1 successors, FD is 28160
via Connected, FastEthernet0/0
remotely connected via remote ingress ip address
P 172.16.10.0/24, 1 successors, FD is 28160
via 10.1.5.2 (28160/25600), FastEthernet0/0
P 192.168.10.0/24, 2 successors, FD is 2172416
via 10.1.3.2 (2172416/28160), Serial0/0/1
via 10.1.2.2 (2172416/28160), Serial0/0/0
P 192.168.20.0/24, 2 successors, FD is 2172416
via 10.1.3.2 (2172416/28160), Serial0/0/1
via 10.1.2.2 (2172416/28160), Serial0/0/0
P 192.168.30.0/24, 1 successors, FD is 2172416
via 10.1.4.2 (2172416/28160), Serial0/1/0
P 192.168.40.0/24, 1 successors, FD is 2172416
via 10.1.4.2 (2172416/28160), Serial0/1/0
Corp#
show ip
eigrp interfaces
local interfaces on Corp, with peer data, 5 total, including VLAN1 (0 peers, no router on this network)
IP-EIGRP interfaces for process 10
Xmit Queue Mean Pacing Time Multicast Pending
Interface Peers Un/Reliable SRTT Un/Reliable Flow Timer Routes
Vlan 0 0/0 1236 0/10 0 0
Fa0/0 1 0/0 1236 0/10 0 0
Se0/0/1 1 0/0 1236 0/10 0 0
Se0/1/0 1 0/0 1236 0/10 0 0
Se0/0/0 1 0/0 1236 0/10 0 0
Corp#
show ip
eigrp neighbors
remote interfaces on the 4 neighboring routers
IP-EIGRP neighbors for process 10
H Address Interface Hold Uptime SRTT RTO Q Seq
(sec) (ms) Cnt Num
0 10.1.2.2 Se0/0/0 14 00:54:33 40 1000 0 58
1 10.1.3.2 Se0/0/1 10 00:54:33 40 1000 0 57
2 10.1.4.2 Se0/1/0 14 00:53:38 40 1000 0 51
3 10.1.5.2 Fa0/0 11 00:52:49 40 1000 0 33
4. Compare OSPF and RIPv1
RIPv1 is distance-vector and supports only classful routing. No VLSM
OSPF is link-state and supports VLSM and classless routing
5. Know how OSPF routers become neighboars and/or adjacent
they become neighbors when they see eachother's hello packets.
area id must match, links must be on the same subnet, hello/dead timers must be the same.
OSPF only shares routes with neigbors who have also established adjacencies. NOT ALL NEIGHBORS become adjacent.
When an OSPF router first receives a hello packet, it verifies that the data in some fields matches its own locally configured information.
Should any of the checked data be different, the hello packet is discarded and not processed. The data fields verified are the Area ID,
Authentication, Network Mask (on broadcast networks), Hello Interval, Router Dead Interval, and Options fields. If this information doesn’t match,
then neighborship is stuck in the down stage.
packetpushers.net
6. Be able to configure single-area OSPF
two commands:
router ospf [process id]
network x.x.x.x y.y.y.y area z
7. Be able to verify the operation of OSPF
Corp#
show ip
protocols
Corp#
show ip
route
Corp#
show ip
ospf
Corp#
show ip
ospf database
Corp#
show ip
ospf interface
Corp#
show ip
ospf neighbor
IOS 15.1
Corp#
show ip
protocols
Routing Protocol is "ospf 132"
Outgoing update filter list for all interfaces is not set
Incoming update filter list for all interfaces is not set
Router ID 10.1.5.1
Number of areas in this router is 1. 1 normal 0 stub 0 nssa
Maximum path: 4
Routing for Networks:
10.1.0.0 0.0.255.255 area 0
Routing Information Sources:
Gateway Distance Last Update
10.1.5.1 110 00:08:51
172.16.10.1 110 00:08:51
192.168.20.1 110 00:12:53
192.168.40.1 110 00:09:35
Distance: (default is 110)
IOS 15.1
Corp#
show ip
route
10.0.0.0/8 is variably subnetted, 10 subnets, 2 masks
C 10.1.1.0/24 is directly connected, Vlan1
L 10.1.1.1/32 is directly connected, Vlan1
C 10.1.2.0/24 is directly connected, Serial0/0/0
L 10.1.2.1/32 is directly connected, Serial0/0/0
C 10.1.3.0/24 is directly connected, Serial0/0/1
L 10.1.3.1/32 is directly connected, Serial0/0/1
C 10.1.4.0/24 is directly connected, Serial0/1/0
L 10.1.4.1/32 is directly connected, Serial0/1/0
C 10.1.5.0/24 is directly connected, FastEthernet0/0
L 10.1.5.1/32 is directly connected, FastEthernet0/0
172.16.0.0/24 is subnetted, 1 subnets
O 172.16.10.0/24 [110/10] via 10.1.5.2, 00:09:09, FastEthernet0/0
O 192.168.10.0/24 [110/65] via 10.1.2.2, 00:13:11, Serial0/0/0
O 192.168.20.0/24 [110/65] via 10.1.2.2, 00:13:01, Serial0/0/0
O 192.168.30.0/24 [110/65] via 10.1.4.2, 00:09:54, Serial0/1/0
O 192.168.40.0/24 [110/65] via 10.1.4.2, 00:09:54, Serial0/1/0
IOS 15.1
Corp#
show ip
ospf
Routing Process "ospf 132" with ID 10.1.5.1
Supports only single TOS(TOS0) routes
Supports opaque LSA
SPF schedule delay 5 secs, Hold time between two SPFs 10 secs
Minimum LSA interval 5 secs. Minimum LSA arrival 1 secs
Number of external LSA 0. Checksum Sum 0x000000
Number of opaque AS LSA 0. Checksum Sum 0x000000
Number of DCbitless external and opaque AS LSA 0
Number of DoNotAge external and opaque AS LSA 0
Number of areas in this router is 1. 1 normal 0 stub 0 nssa
External flood list length 0
Area BACKBONE(0)
Number of interfaces in this area is 5
Area has no authentication
SPF algorithm executed 7 times
Area ranges are
Number of LSA 5. Checksum Sum 0x034486
Number of opaque link LSA 0. Checksum Sum 0x000000
Number of DCbitless LSA 0
Number of indication LSA 0
Number of DoNotAge LSA 0
Flood list length 0
IOS 15.1
Corp#
show ip
ospf database
OSPF Router with ID (10.1.5.1) (Process ID 132)
Router Link States (Area 0)
Link ID ADV Router Age Seq# Checksum Link count
192.168.20.1 192.168.20.1 854 0x80000006 0x00ae08 6
192.168.40.1 192.168.40.1 656 0x80000004 0x006bc6 4
10.1.5.1 10.1.5.1 612 0x8000000f 0x00ab77 8
172.16.10.1 172.16.10.1 612 0x80000003 0x00b30d 2
Net Link States (Area 0)
Link ID ADV Router Age Seq# Checksum
10.1.5.1 10.1.5.1 612 0x80000001 0x00cc34
ADV Router aka RID/Router ID, the highest IP address on the router
we are seeing three connected routers + our own router (Corp at 10.1.5.1)
IOS 15.1
Corp#
show ip
ospf interface
Vlan1 is up, line protocol is up
Internet address is 10.1.1.1/24, Area 0
Process ID 132, Router ID 10.1.5.1, Network Type BROADCAST, Cost: 1
Transmit Delay is 1 sec, State DR, Priority 1
Designated Router (ID) 10.1.5.1, Interface address 10.1.1.1
No backup designated router on this network
Timer intervals configured, Hello 10, Dead 40, Wait 40, Retransmit 5
Hello due in 00:00:08
Index 1/1, flood queue length 0
Next 0x0(0)/0x0(0)
Last flood scan length is 1, maximum is 1
Last flood scan time is 0 msec, maximum is 0 msec
Neighbor Count is 0, Adjacent neighbor count is 0
Suppress hello for 0 neighbor(s)
FastEthernet0/0 is up, line protocol is up
Internet address is 10.1.5.1/24, Area 0
Process ID 132, Router ID 10.1.5.1, Network Type BROADCAST, Cost: 1
Transmit Delay is 1 sec, State DR, Priority 1
Designated Router (ID) 10.1.5.1, Interface address 10.1.5.1
Backup Designated Router (ID) 172.16.10.1, Interface address 10.1.5.2
Timer intervals configured, Hello 10, Dead 40, Wait 40, Retransmit 5
Hello due in 00:00:07
Index 2/2, flood queue length 0
Next 0x0(0)/0x0(0)
Last flood scan length is 1, maximum is 1
Last flood scan time is 0 msec, maximum is 0 msec
Neighbor Count is 1, Adjacent neighbor count is 1
Adjacent with neighbor 172.16.10.1 (Backup Designated Router)
Suppress hello for 0 neighbor(s)
Serial0/0/1 is up, line protocol is up
Internet address is 10.1.3.1/24, Area 0
Process ID 132, Router ID 10.1.5.1, Network Type POINT-TO-POINT, Cost: 64
Transmit Delay is 1 sec, State POINT-TO-POINT,
Timer intervals configured, Hello 10, Dead 40, Wait 40, Retransmit 5
Hello due in 00:00:07
Index 3/3, flood queue length 0
Next 0x0(0)/0x0(0)
Last flood scan length is 1, maximum is 1
Last flood scan time is 0 msec, maximum is 0 msec
Neighbor Count is 1 , Adjacent neighbor count is 1
Adjacent with neighbor 192.168.20.1
Suppress hello for 0 neighbor(s)
Serial0/1/0 is up, line protocol is up
Internet address is 10.1.4.1/24, Area 0
Process ID 132, Router ID 10.1.5.1, Network Type POINT-TO-POINT, Cost: 64
Transmit Delay is 1 sec, State POINT-TO-POINT,
Timer intervals configured, Hello 10, Dead 40, Wait 40, Retransmit 5
Hello due in 00:00:07
Index 4/4, flood queue length 0
Next 0x0(0)/0x0(0)
Last flood scan length is 1, maximum is 1
Last flood scan time is 0 msec, maximum is 0 msec
Neighbor Count is 1 , Adjacent neighbor count is 1
Adjacent with neighbor 192.168.40.1
Suppress hello for 0 neighbor(s)
Serial0/0/0 is up, line protocol is up
Internet address is 10.1.2.1/24, Area 0
Process ID 132, Router ID 10.1.5.1, Network Type POINT-TO-POINT, Cost: 64
Transmit Delay is 1 sec, State POINT-TO-POINT,
Timer intervals configured, Hello 10, Dead 40, Wait 40, Retransmit 5
Hello due in 00:00:07
Index 5/5, flood queue length 0
Next 0x0(0)/0x0(0)
Last flood scan length is 1, maximum is 1
Last flood scan time is 0 msec, maximum is 0 msec
Neighbor Count is 1 , Adjacent neighbor count is 1
Adjacent with neighbor 192.168.20.1
Suppress hello for 0 neighbor(s)
IOS 15.1
Corp#
show ip
ospf neighbor
Neighbor ID Pri State Dead Time Address Interface
192.168.20.1 0 FULL/ - 00:00:31 10.1.3.2 Serial0/0/1
192.168.40.1 0 FULL/ - 00:00:33 10.1.4.2 Serial0/1/0
192.168.20.1 0 FULL/ - 00:00:31 10.1.2.2 Serial0/0/0
172.16.10.1 1 FULL/BDR 00:00:32 10.1.5.2 FastEthernet0/0
Flashcards
Chapter 9 Written Lab 9.0
1. What four routed protocols are supported by EIGRP?
IPX, IPv4, IPv6, AppleTalk
2. When is redistribution required for EIGRP?
when there are multiple autonomous systems
redistribution is required when more than one EIGRP session or process is running and they are identified with different ASNs.
redistribution shares toplogy information between EIGRP sessions
3. What command would be used to enable EIGRP with an autonmous system number of 300?
router eigrp 300
4. What command will tell EIGRP that it is connected to network 172.10.0.0?
network 172.10.0.0
5. What type of EIGRP interface will neither send nor receive Hello packets?
passive-interface s0/0
6. Write the command that will enable OSPF process 101 on a router
router ospf 101
7. Write the command that will display details of all OSFP routing processes enabled on a router
show ip ospf
8. Write the command that will display interface-specific OSPF information
show ip ospf interface
9. Write the command that will display all OSPF neighbors
show ip ospf neighbor
10. Write the command that will display all different OSPF route types that are currently known by the router
show ip route ospf
Chapter 9 Hands-On Labs
Build the network and configure interfaces
LabA(config)#
int f0/0
LabA(config-if)#
ip addr 172.16.10.1 255.255.255.0
LabA(config-if)#
no shut
LabB(config)#
int f0/0
LabB(config-if)#
ip addr 172.16.10.2 255.255.255.0
LabB(config-if)#
no shut
LabB(config-if)#
int s0/0/0
LabB(config-if)#
ip addr 172.16.20.1 255.255.255.0
LabB(config-if)#
no shut
LabC(config)#
int f0/0
LabC(config-if)#
ip addr 172.16.30.1 255.255.255.0
LabC(config-if)#
no shut
LabC(config-if)#
int s0/0/0
LabC(config-if)#
ip addr 172.16.20.2 255.255.255.0
LabC(config-if)#
no shut
LabC(config-if)#
int s0/0/1
LabC(config-if)#
ip addr 172.16.40.1 255.255.255.0
LabC(config-if)#
no shut
LabD(config)#
int s0/0/0
LabD(config-if)#
ip addr 172.16.40.2 255.255.255.0
LabD(config-if)#
no shut
LabD(config-if)#
int f0/0
LabD(config-if)#
ip addr 172.16.50.1 255.255.255.0
LabD(config-if)#
no shut
9.1 - Configure and Verfiy EIGRP
configure EIGRP on all 4 routers and observe results
LabA
LabA(config)#
router eigrp 100
LabA(config-router)#
net 172.16.0.0
[no output]
LabA#
show ip eigrp neighbors
IP-EIGRP neighbors for process 100
LabA#
show ip eigrp topology
IP-EIGRP Topology Table for AS 100/ID(172.16.10.1)
Codes: P - Passive, A - Active, U - Update, Q - Query, R - Reply,
r - Reply status
P 172.16.10.0/24, 1 successors, FD is 28160
via Connected, FastEthernet0/0
LabA#
show ip eigrp interfaces
IP-EIGRP interfaces for process 100
Xmit Queue Mean Pacing Time Multicast Pending
Interface Peers Un/Reliable SRTT Un/Reliable Flow Timer Routes
Fa0/0 0 0/0 1236 0/10 0 0
no neighbors at this point since EIGRP is only active on this router. One successor AKA route, which is the connection out of this router.
But note that we have no information about what's on the other side of that link
LabB
LabB(config)#
router eigrp 100
LabB(config-router)#
net 172.16.0.0
%DUAL-5-NBRCHANGE: IP-EIGRP 100:
Neighbor 172.16.10.1 (FastEthernet0/0) is up: new adjacency
LabB#
show ip eigrp neighbors
IP-EIGRP neighbors for process 100
H Address Interface Hold Uptime SRTT RTO Q Seq
(sec) (ms) Cnt Num
0 172.16.10.1 Fa0/0 12 00:00:14 40 1000 0 1
LabB#
show ip eigrp topology
IP-EIGRP Topology Table for AS 100/ID(172.16.20.1)
Codes: P - Passive, A - Active, U - Update, Q - Query, R - Reply,
r - Reply status
P 172.16.10.0/24, 1 successors, FD is 28160
via Connected, FastEthernet0/0
P 172.16.20.0/24, 1 successors, FD is 2169856
via Connected, Serial0/0/0
LabB#
show ip eigrp interfaces
IP-EIGRP interfaces for process 100
Xmit Queue Mean Pacing Time Multicast Pending
Interface Peers Un/Reliable SRTT Un/Reliable Flow Timer Routes
Fa0/0 1 0/0 1236 0/10 0 0
Se0/0/0 0 0/0 1236 0/10 0 0
We can see a neighbor at .1
We now have two paths out of this router. Left to neighbor. Exit at right is available as successor(route), but again we have no info about
what is on the other side, since that router has no EIGRP yet (s0/0/0 has no peers, but is an EIGRP interface)
LabC
LabC(config)#
router eigrp 100
LabC(config-router)#
net 172.16.0.0
%DUAL-5-NBRCHANGE: IP-EIGRP 100:
Neighbor 172.16.20.1 (Serial0/0/0) is up: new adjacency
LabC#
show ip eigrp neighbors
IP-EIGRP neighbors for process 100
H Address Interface Hold Uptime SRTT RTO Q Seq
(sec) (ms) Cnt Num
0 172.16.20.1 Se0/0/0 12 00:00:25 40 1000 0 8
LabC#
show ip eigrp toplogy
IP-EIGRP Topology Table for AS 100/ID(172.16.40.1)
Codes: P - Passive, A - Active, U - Update, Q - Query, R - Reply,
r - Reply status
P 172.16.10.0/24, 1 successors, FD is 2172416
via 172.16.20.1 (2172416/28160), Serial0/0/0
P 172.16.20.0/24, 1 successors, FD is 2169856
via Connected, Serial0/0/0
P 172.16.30.0/24, 1 successors, FD is 28160
via Connected, FastEthernet0/0
P 172.16.40.0/24, 1 successors, FD is 2169856
via Connected, Serial0/0/1
LabC#
show ip eigrp interfaces
IP-EIGRP interfaces for process 100
Xmit Queue Mean Pacing Time Multicast Pending
Interface Peers Un/Reliable SRTT Un/Reliable Flow Timer Routes
Fa0/0 0 0/0 1236 0/10 0 0
Se0/0/0 1 0/0 1236 0/10 0 0
Se0/0/1 0 0/0 1236 0/10 0 0
.1 router B interface is now a neighbor.
LabC topology shows the 3 direct connected networks AND the network on the other side of LabB since LabB is our EIGRP neighbor
3 eigrp interfaces:
Fa0/0 is ours at LabC- no peers bc there is no eigrp router on the other end
s0/0/0 is our interface out left to LabB which is an EIGRP peer
s0/0/1 is our interface out right which does not see an EIGRP peer but does put that net 172.16.40.0 in our topology
LabD
LabD(config)#
router eigrp 100
LabD(config-router)#
net 172.16.0.0
%DUAL-5-NBRCHANGE: IP-EIGRP 100:
Neighbor 172.16.40.1 (Serial0/0/0) is up: new adjacency
LabD#
show ip eigrp neighbors
IP-EIGRP neighbors for process 100
H Address Interface Hold Uptime SRTT RTO Q Seq
(sec) (ms) Cnt Num
0 172.16.40.1 Se0/0/0 11 00:00:14 40 1000 0 6
LabD#
show ip eigrp topology
IP-EIGRP Topology Table for AS 100/ID(172.16.50.1)
Codes: P - Passive, A - Active, U - Update, Q - Query, R - Reply,
r - Reply status
P 172.16.10.0/24, 1 successors, FD is 2684416
via 172.16.40.1 (2684416/2172416), Serial0/0/0
P 172.16.20.0/24, 1 successors, FD is 2681856
via 172.16.40.1 (2681856/2169856), Serial0/0/0
P 172.16.30.0/24, 1 successors, FD is 2172416
via 172.16.40.1 (2172416/28160), Serial0/0/0
P 172.16.40.0/24, 1 successors, FD is 2169856
via Connected, Serial0/0/0
P 172.16.50.0/24, 1 successors, FD is 28160
via Connected, FastEthernet0/0
LabD#
show ip eigrp interfaces
IP-EIGRP interfaces for process 100
Xmit Queue Mean Pacing Time Multicast Pending
Interface Peers Un/Reliable SRTT Un/Reliable Flow Timer Routes
Fa0/0 0 0/0 1236 0/10 0 0
Se0/0/0 1 0/0 1236 0/10 0 0
LabC to our left is now a neighbor at 172.16.40.1
toplogy shows a route out to the right (no router on that end)
a route to the left to LabC .40.0
the .10.0, .20.0, and .30.0 networks via info from LabC
2 eigrp interfaces-
fa0/0 out to the right
s0/0/0 out left to LabC
Time to remove EIGRP from all four routers to prepare for the OSPF lab next,
since EIGRP has a lower AD than OSPF
LabA(config)#
no router eigrp 100
LabB(config)#
no router eigrp 100
LabC(config)#
no router eigrp 100
LabD(config)#
no router eigrp 100
9.2 - Enabling the OSPF Process
9.3 - Configuring OSPF Interfaces
9.4 - Verifying OSPF Operation
LabA
LabA(config)#
router ospf 100
LabA(config-router)#
net 172.16.10.1 0.0.0.0 area 0
[no output]
LabA#
show ip ospf neighbor
[no output]
LabA#
show ip ospf database
OSPF Router with ID (172.16.10.1) (Process ID 100)
Router Link States (Area 0)
Link ID ADV Router Age Seq# Checksum Link count
172.16.10.1 172.16.10.1 44 0x80000001 0x00b24b 1
LabA#
show ip ospf interface
FastEthernet0/0 is up, line protocol is up
Internet address is 172.16.10.1/24, Area 0
Process ID 100, Router ID 172.16.10.1, Network Type BROADCAST, Cost: 1
Transmit Delay is 1 sec, State DR, Priority 1
Designated Router (ID) 172.16.10.1, Interface address 172.16.10.1
No backup designated router on this network
Timer intervals configured, Hello 10, Dead 40, Wait 40, Retransmit 5
Hello due in 00:00:08
Index 1/1, flood queue length 0
Next 0x0(0)/0x0(0)
Last flood scan length is 1, maximum is 1
Last flood scan time is 0 msec, maximum is 0 msec
Neighbor Count is 0, Adjacent neighbor count is 0
Suppress hello for 0 neighbor(s)
we're including this router's interface 172.16.10.1 in our ospf area 0
fa0/0 now registers as an ospf interface
the ospf database includes data about this link only.... LabA is counting itself(10.1) as ADVERTISTING router?
the designated router is .1 LabA
LabB
LabB(config)#
router ospf 101
LabB(config-router)#
net 172.16.10.2 0.0.0.0 area 0
LabB(config-router)#
net 172.16.20.1 0.0.0.0 area 0
01:26:36: %OSPF-5-ADJCHG: Process 101, Nbr 172.16.10.1
on FastEthernet0/0 from LOADING to FULL, Loading Done
LabB#
show ip ospf neighbor
Neighbor ID Pri State Dead Time Address Interface
172.16.10.1 1 FULL/DR 00:00:33 172.16.10.1
LabB#
show ip ospf database
OSPF Router with ID (172.16.20.1) (Process ID 101)
Router Link States (Area 0)
Link ID ADV Router Age Seq# Checksum Link count
172.16.10.1 172.16.10.1 145 0x80000002 0x0067cd 1
172.16.20.1 172.16.20.1 32 0x80000003 0x006e8f 2
Net Link States (Area 0)
Link ID ADV Router Age Seq# Checksum
172.16.10.1 172.16.10.1 145 0x80000001 0x00953d
LabB#
show ip ospf interface
FastEthernet0/0 is up, line protocol is up
Internet address is 172.16.10.2/24, Area 0
Process ID 101, Router ID 172.16.20.1, Network Type BROADCAST, Cost: 1
Transmit Delay is 1 sec, State BDR, Priority 1
Designated Router (ID) 172.16.10.1, Interface address 172.16.10.1
Backup Designated Router (ID) 172.16.20.1, Interface address 172.16.10.2
Timer intervals configured, Hello 10, Dead 40, Wait 40, Retransmit 5
Hello due in 00:00:03
Index 1/1, flood queue length 0
Next 0x0(0)/0x0(0)
Last flood scan length is 1, maximum is 1
Last flood scan time is 0 msec, maximum is 0 msec
Neighbor Count is 1, Adjacent neighbor count is 1
Adjacent with neighbor 172.16.10.1 (Designated Router)
Suppress hello for 0 neighbor(s)
Serial0/0/0 is up, line protocol is up
Internet address is 172.16.20.1/24, Area 0
Process ID 101, Router ID 172.16.20.1, Network Type POINT-TO-POINT, Cost: 64
Transmit Delay is 1 sec, State POINT-TO-POINT,
Timer intervals configured, Hello 10, Dead 40, Wait 40, Retransmit 5
Hello due in 00:00:04
Index 2/2, flood queue length 0
Next 0x0(0)/0x0(0)
Last flood scan length is 1, maximum is 1
Last flood scan time is 0 msec, maximum is 0 msec
Suppress hello for 0 neighbor(s)
We've include the two interfaces on this router in the OSPF area
and can now see Router A's interface 10.1 to the left as a neighbor in the area
the "OSPF Database" now shows two links 20.1(local) and 10.1(neighbor) as 'router link states'.
"ADV Router" means advertising router for the two links. The link address is used as the advertising router.
database shows "Net Link States" category with one entry- 172.16.10.1 which is the address of neighbor router to our left
we have two local OSPF interfaces- f0/0 and s0/0/0
LabC
LabC(config)#
router ospf 102
LabC(config-router)#
net 172.16.20.2 0.0.0.0 area 0
LabC(config-router)#
net 172.16.30.1 0.0.0.0 area 0
LabC(config-router)#
net 172.16.40.1 0.0.0.0 area 0
01:33:54: %OSPF-5-ADJCHG: Process 102, Nbr 172.16.20.1
on Serial0/0/0 from LOADING to FULL, Loading Done
LabC#
show ip ospf neighbor
Neighbor ID Pri State Dead Time Address Interface
172.16.20.1 0 FULL/ - 00:00:30 172.16.20.1 Serial0/0/0
LabC#
show ip ospf database
OSPF Router with ID (172.16.40.1) (Process ID 102)
Router Link States (Area 0)
Link ID ADV Router Age Seq# Checksum Link count
172.16.10.1 172.16.10.1 542 0x80000002 0x0067cd 1
172.16.20.1 172.16.20.1 90 0x80000004 0x00a551 3
172.16.40.1 172.16.40.1 37 0x80000004 0x00e47c 4
Net Link States (Area 0)
Link ID ADV Router Age Seq# Checksum
172.16.10.1 172.16.10.1 542 0x80000001 0x00953d
LabC#
show ip ospf interface
Serial0/0/0 is up, line protocol is up
Internet address is 172.16.20.2/24, Area 0
Process ID 102, Router ID 172.16.40.1, Network Type POINT-TO-POINT, Cost: 64
Transmit Delay is 1 sec, State POINT-TO-POINT,
Timer intervals configured, Hello 10, Dead 40, Wait 40, Retransmit 5
Hello due in 00:00:01
Index 1/1, flood queue length 0
Next 0x0(0)/0x0(0)
Last flood scan length is 1, maximum is 1
Last flood scan time is 0 msec, maximum is 0 msec
Neighbor Count is 1 , Adjacent neighbor count is 1
Adjacent with neighbor 172.16.20.1
Suppress hello for 0 neighbor(s)
FastEthernet0/0 is up, line protocol is up
Internet address is 172.16.30.1/24, Area 0
Process ID 102, Router ID 172.16.40.1, Network Type BROADCAST, Cost: 1
Transmit Delay is 1 sec, State DR, Priority 1
Designated Router (ID) 172.16.40.1, Interface address 172.16.30.1
No backup designated router on this network
Timer intervals configured, Hello 10, Dead 40, Wait 40, Retransmit 5
Hello due in 00:00:02
Index 2/2, flood queue length 0
Next 0x0(0)/0x0(0)
Last flood scan length is 1, maximum is 1
Last flood scan time is 0 msec, maximum is 0 msec
Neighbor Count is 0, Adjacent neighbor count is 0
Suppress hello for 0 neighbor(s)
Serial0/0/1 is up, line protocol is up
Internet address is 172.16.40.1/24, Area 0
Process ID 102, Router ID 172.16.40.1, Network Type POINT-TO-POINT, Cost: 64
Transmit Delay is 1 sec, State POINT-TO-POINT,
Timer intervals configured, Hello 10, Dead 40, Wait 40, Retransmit 5
Hello due in 00:00:08
Index 3/3, flood queue length 0
Next 0x0(0)/0x0(0)
Last flood scan length is 1, maximum is 1
Last flood scan time is 0 msec, maximum is 0 msec
Suppress hello for 0 neighbor(s)
we include the three nets conneted to labC in the area.. 20.0, 30.0, and 40.0
link to our left, 20.1 is visible as "Neighbor"
OSPF Database-
Router Link States are
10.1(Router A)
20.1(Router B)
40.1(Router C)(This router)
Net Link States
10.1(Router A)... why does only Router A show here?
Reference- router link state vs net link state
Router Link States are type 1 LSAs. It lists all the routers in the area and the number of interfaces. 40.1 has 4 interfaces
Net Link States are the multi-access networks (Type 2 LSAs). The ADV (advertising router) is the DR.
LabD
LabD(config)#
router ospf 103
LabD(config-router)#
net 172.16.40.2 0.0.0.0 area 0
LabD(config-router)#
net 172.16.50.1 0.0.0.0 area 0
01:37:11: %OSPF-5-ADJCHG: Process 103, Nbr 172.16.40.1
on Serial0/0/0 from LOADING to FULL, Loading Done
LabD#
show ip ospf neighbor
Neighbor ID Pri State Dead Time Address Interface
172.16.40.1 0 FULL/ - 00:00:32 172.16.40.1 Serial0/0/0
LabD#
show ip ospf database
OSPF Router with ID (172.16.50.1) (Process ID 103)
Router Link States (Area 0)
Link ID ADV Router Age Seq# Checksum Link count
172.16.10.1 172.16.10.1 785 0x80000002 0x0067cd 1
172.16.20.1 172.16.20.1 333 0x80000004 0x00a551 3
172.16.40.1 172.16.40.1 111 0x80000005 0x00013b 5
172.16.50.1 172.16.50.1 53 0x80000003 0x001023 3
Net Link States (Area 0)
Link ID ADV Router Age Seq# Checksum
172.16.10.1 172.16.10.1 785 0x80000001 0x00953d
LabD#
show ip ospf interface
Serial0/0/0 is up, line protocol is up
Internet address is 172.16.40.2/24, Area 0
Process ID 103, Router ID 172.16.50.1, Network Type POINT-TO-POINT, Cost: 64
Transmit Delay is 1 sec, State POINT-TO-POINT,
Timer intervals configured, Hello 10, Dead 40, Wait 40, Retransmit 5
Hello due in 00:00:01
Index 1/1, flood queue length 0
Next 0x0(0)/0x0(0)
Last flood scan length is 1, maximum is 1
Last flood scan time is 0 msec, maximum is 0 msec
Neighbor Count is 1 , Adjacent neighbor count is 1
Adjacent with neighbor 172.16.40.1
Suppress hello for 0 neighbor(s)
FastEthernet0/0 is up, line protocol is up
Internet address is 172.16.50.1/24, Area 0
Process ID 103, Router ID 172.16.50.1, Network Type BROADCAST, Cost: 1
Transmit Delay is 1 sec, State WAITING, Priority 1
No designated router on this network
No backup designated router on this network
Timer intervals configured, Hello 10, Dead 40, Wait 40, Retransmit 5
Hello due in 00:00:04
Index 2/2, flood queue length 0
Next 0x0(0)/0x0(0)
Last flood scan length is 1, maximum is 1
Last flood scan time is 0 msec, maximum is 0 msec
Neighbor Count is 0, Adjacent neighbor count is 0
Suppress hello for 0 neighbor(s)
observations
the OSPF databases now match across all 4 routers.
NOTE that this is a database of routers, identified by
router ID. It is not a topology that lists routers AND routes,
like in the "equivalent" eigrp command.show eigrp topology
----------------------------------------------------------------------------------
PAUSE- a tale of a misconfigured network
After a 9 month hiatus, I am reviewing this book and have made it back to Chapter 9. I'm studing this webpage, working thorough the OSPF configurations
described above, and I get stuck on the concept of "link count" under "Router Link States" found in the output of show ip ospf database
The structure of the notes above is helpful, because I was tracking the state of each router BEFORE i made changes to the subsquent router. But just to be sure,
today I decided to recreate the topology, then configure each router one at a time, noting the results as I went.
And I ran into some problems.
Here is the original topology:
And today's recreated toplogy:
After replicating the toplogy and programming the IP addresses on each router, I started on configurations, just like before:
LabA
LabA(config)#
router ospf 100
LabA(config-router)#
net 172.16.10.1 0.0.0.0 area 0
[no output]
LabA#
show ip ospf neighbor
[no output]
LabA#
show ip ospf database
OSPF Router with ID (172.16.10.1) (Process ID 100)
Router Link States (Area 0)
Link ID ADV Router Age Seq# Checksum Link count
172.16.10.1 172.16.10.1 44 0x80000001 0x00b24b 1
LabA#
show ip ospf interface
FastEthernet0/0 is up, line protocol is up
Internet address is 172.16.10.1/24, Area 0
Process ID 100, Router ID 172.16.10.1, Network Type BROADCAST, Cost: 1
Transmit Delay is 1 sec, State DR, Priority 1
Designated Router (ID) 172.16.10.1, Interface address 172.16.10.1
No backup designated router on this network
Timer intervals configured, Hello 10, Dead 40, Wait 40, Retransmit 5
Hello due in 00:00:08
Index 1/1, flood queue length 0
Next 0x0(0)/0x0(0)
Last flood scan length is 1, maximum is 1
Last flood scan time is 0 msec, maximum is 0 msec
Neighbor Count is 0, Adjacent neighbor count is 0
Suppress hello for 0 neighbor(s)
good so far.... On to LabB router
LabB
LabB(config)#
router ospf 101
LabB(config-router)#
net 172.16.10.2 0.0.0.0 area 0
LabB(config-router)#
net 172.16.20.1 0.0.0.0 area 0
01:26:36: %OSPF-5-ADJCHG: Process 101, Nbr 172.16.10.1
on FastEthernet0/0 from LOADING to FULL, Loading Done
LabB#
show ip ospf neighbor
Neighbor ID Pri State Dead Time Address Interface
172.16.10.1 1 FULL/DR 00:00:33 172.16.10.1
LabB#
show ip ospf database
OSPF Router with ID (172.16.20.1) (Process ID 101)
Router Link States (Area 0)
Link ID ADV Router Age Seq# Checksum Link count
172.16.10.1 172.16.10.1 145 0x80000002 0x0067cd 1
172.16.20.1 172.16.20.1 32 0x80000003 0x006e8f 2
Net Link States (Area 0)
Link ID ADV Router Age Seq# Checksum
172.16.10.1 172.16.10.1 145 0x80000001 0x00953d
LabB#
show ip ospf interface
FastEthernet0/0 is up, line protocol is up
Internet address is 172.16.10.2/24, Area 0
Process ID 101, Router ID 172.16.20.1, Network Type BROADCAST, Cost: 1
Transmit Delay is 1 sec, State BDR, Priority 1
Designated Router (ID) 172.16.10.1, Interface address 172.16.10.1
Backup Designated Router (ID) 172.16.20.1, Interface address 172.16.10.2
Timer intervals configured, Hello 10, Dead 40, Wait 40, Retransmit 5
Hello due in 00:00:03
Index 1/1, flood queue length 0
Next 0x0(0)/0x0(0)
Last flood scan length is 1, maximum is 1
Last flood scan time is 0 msec, maximum is 0 msec
Neighbor Count is 1, Adjacent neighbor count is 1
Adjacent with neighbor 172.16.10.1 (Designated Router)
Suppress hello for 0 neighbor(s)
Serial0/0/0 is up, line protocol is up
Internet address is 172.16.20.1/24, Area 0
Process ID 101, Router ID 172.16.20.1, Network Type POINT-TO-POINT, Cost: 64
Transmit Delay is 1 sec, State POINT-TO-POINT,
Timer intervals configured, Hello 10, Dead 40, Wait 40, Retransmit 5
Hello due in 00:00:04
Index 2/2, flood queue length 0
Next 0x0(0)/0x0(0)
Last flood scan length is 1, maximum is 1
Last flood scan time is 0 msec, maximum is 0 msec
Suppress hello for 0 neighbor(s)
still looks good; same as before.... On to LabC router
LabC
LabC(config)#
router ospf 102
LabC(config-router)#
net 172.16.20.2 0.0.0.0 area 0
LabC(config-router)#
net 172.16.30.1 0.0.0.0 area 0
LabC(config-router)#
net 172.16.40.1 0.0.0.0 area 0
01:33:54: %OSPF-5-ADJCHG: Process 102, Nbr 172.16.20.1
on Serial0/0/0 from LOADING to FULL, Loading Done
LabC#
show ip ospf neighbor
[no output]
And here is where I ran into trouble. The show ip ospf neighbor command returns nothing. How can
that be?
After awhile I realized it is due to a misconfiguration in the topology.
For Lab C, I programmed the interfaces as follows:
LabC(config)#
int f0/0
LabC(config-if)#
ip addr 172.16.30.1 255.255.255.0
LabC(config-if)#
no shut
LabC(config-if)#
int s0/0/0
LabC(config-if)#
ip addr 172.16.20.2 255.255.255.0
LabC(config-if)#
no shut
LabC(config-if)#
int s0/0/1
LabC(config-if)#
ip addr 172.16.40.1 255.255.255.0
LabC(config-if)#
no shut
and again here is the topology for that router:
but here is what it SHOULD HAVE looked like (as it did the first time I built it)
S0/0/0 and S0/0/1 are swapped. When I gave the IP 172.16.20.2 to s/0/0/0, thinking that was the interface on the left side
which faces Lab B, I was actually giving 172.16.20.2 to the right side, facing LabC (which has no OSPF configs yet.)
Since the left side got got the IP intended for the right side which was 172.16.40.1
the inverse also occured-
the right side got the IP intended for the left which was 172.16.20.2
LabC left side should have been
s0/0/0 with 20.2
and LabC right side should have been
s0/0/1 with 40.1
The correct IPs were mapped to the correct interfaces. But the mistake happened before I even programmed them.
When I made the connections from LabB to LabC and from LabD to LabC, I plugged then into the wrong ports.
Interestingly.. not only is this causing OSPF to not see B as a neighbor from C.. but B and C cannot ping eachother either.
@B the config is 172.16.20.1/24 @ S0/0/0
@C the config is 172.16.40.1/24 @ S/0/0/1
meaning they are not even on the same network! But the system is not throwing any errors or bringing it to my attention.
It just fails to connect.
To correct the issue, I simply deleted those two links and re-created them. Worth noting, I used the auto select cable here,
which does not ask which interface you want to use when attaching. Earlier I must have plugged the right side first, and
auto select plugged into 0/0/0.
This time I plugged into left side first.
Now LabC OSPF data is reading out correctly...
LabC
LabC(config)#
router ospf 102
LabC(config-router)#
net 172.16.20.2 0.0.0.0 area 0
LabC(config-router)#
net 172.16.30.1 0.0.0.0 area 0
LabC(config-router)#
net 172.16.40.1 0.0.0.0 area 0
01:33:54: %OSPF-5-ADJCHG: Process 102, Nbr 172.16.20.1
on Serial0/0/0 from LOADING to FULL, Loading Done
LabC#
show ip ospf neighbor
Neighbor ID Pri State Dead Time Address Interface
172.16.20.1 0 FULL/ - 00:00:30 172.16.20.1 Serial0/0/0
LabC#
show ip ospf database
OSPF Router with ID (172.16.40.1) (Process ID 102)
Router Link States (Area 0)
Link ID ADV Router Age Seq# Checksum Link count
172.16.10.1 172.16.10.1 542 0x80000002 0x0067cd 1
172.16.20.1 172.16.20.1 90 0x80000004 0x00a551 3
172.16.40.1 172.16.40.1 37 0x80000004 0x00e47c 4
Net Link States (Area 0)
Link ID ADV Router Age Seq# Checksum
172.16.10.1 172.16.10.1 542 0x80000001 0x00953d
LabC#
show ip ospf interface
Serial0/0/0 is up, line protocol is up
Internet address is 172.16.20.2/24, Area 0
Process ID 102, Router ID 172.16.40.1, Network Type POINT-TO-POINT, Cost: 64
Transmit Delay is 1 sec, State POINT-TO-POINT,
Timer intervals configured, Hello 10, Dead 40, Wait 40, Retransmit 5
Hello due in 00:00:01
Index 1/1, flood queue length 0
Next 0x0(0)/0x0(0)
Last flood scan length is 1, maximum is 1
Last flood scan time is 0 msec, maximum is 0 msec
Neighbor Count is 1 , Adjacent neighbor count is 1
Adjacent with neighbor 172.16.20.1
Suppress hello for 0 neighbor(s)
FastEthernet0/0 is up, line protocol is up
Internet address is 172.16.30.1/24, Area 0
Process ID 102, Router ID 172.16.40.1, Network Type BROADCAST, Cost: 1
Transmit Delay is 1 sec, State DR, Priority 1
Designated Router (ID) 172.16.40.1, Interface address 172.16.30.1
No backup designated router on this network
Timer intervals configured, Hello 10, Dead 40, Wait 40, Retransmit 5
Hello due in 00:00:02
Index 2/2, flood queue length 0
Next 0x0(0)/0x0(0)
Last flood scan length is 1, maximum is 1
Last flood scan time is 0 msec, maximum is 0 msec
Neighbor Count is 0, Adjacent neighbor count is 0
Suppress hello for 0 neighbor(s)
Serial0/0/1 is up, line protocol is up
Internet address is 172.16.40.1/24, Area 0
Process ID 102, Router ID 172.16.40.1, Network Type POINT-TO-POINT, Cost: 64
Transmit Delay is 1 sec, State POINT-TO-POINT,
Timer intervals configured, Hello 10, Dead 40, Wait 40, Retransmit 5
Hello due in 00:00:08
Index 3/3, flood queue length 0
Next 0x0(0)/0x0(0)
Last flood scan length is 1, maximum is 1
Last flood scan time is 0 msec, maximum is 0 msec
Suppress hello for 0 neighbor(s)
Which brings me to the original reason I re-created this topology... I was confused about the LINK COUNTS
here:
OSPF Router with ID (172.16.40.1) (Process ID 102)
Router Link States (Area 0)
Link ID ADV Router Age Seq# Checksum Link count
172.16.10.1 172.16.10.1 542 0x80000002 0x0067cd 1
172.16.20.1 172.16.20.1 90 0x80000004 0x00a551 3
172.16.40.1 172.16.40.1 37 0x80000004 0x00e47c 4
Net Link States (Area 0)
Link ID ADV Router Age Seq# Checksum
172.16.10.1 172.16.10.1 542 0x80000001 0x00953d
The steps of recreating the lab were helpful, but this link answered the question:
Here is the output of each router's command show ip ospf interface as they are
set up one at a time.
LabA - No OSPF at B, C, or D yet
show ip ospf database
OSPF Router with ID (172.16.10.1) (Process ID 100)
Router Link States (Area 0)
Link ID ADV Router Age Seq# Checksum Link count
172.16.10.1 172.16.10.1 44 0x80000001 0x00b24b 1
LabB - No OSPF at C or D yet
show ip ospf database
OSPF Router with ID (172.16.20.1) (Process ID 101)
Router Link States (Area 0)
Link ID ADV Router Age Seq# Checksum Link count
172.16.10.1 172.16.10.1 145 0x80000002 0x0067cd 1
172.16.20.1 172.16.20.1 32 0x80000003 0x006e8f 2
Net Link States (Area 0)
Link ID ADV Router Age Seq# Checksum
172.16.10.1 172.16.10.1 145 0x80000001 0x00953d
the 20.2 interface on this router has 2 ospf links.
The left-facing out to RA, a crossover cable
The right-facing out to RC, a serial cable.
If the solution I found is correct, why is this serial link not being counted twice? The solution (I think)
is revealed after the configuration of the next router...
LabC - No OSPF at D yet
show ip ospf database
OSPF Router with ID (172.16.40.1) (Process ID 102)
Router Link States (Area 0)
Link ID ADV Router Age Seq# Checksum Link count
172.16.10.1 172.16.10.1 542 0x80000002 0x0067cd 1
172.16.20.1 172.16.20.1 90 0x80000004 0x00a551 3
172.16.40.1 172.16.40.1 37 0x80000004 0x00e47c 4
Net Link States (Area 0)
Link ID ADV Router Age Seq# Checksum
172.16.10.1 172.16.10.1 542 0x80000001 0x00953d
NOW we can see that the 20.1 link, which is the right-facing interface on LabB.. aka the router ID..
has THREE OSPF links.
Nothing changed on the left side of B. But on the right side, we now have an active OSPF router at the
other end of the link. This leads me to believe that the forum post was correct that 'serial links are counted twice',
but, more specifically, BOTH ENDS of the serial(PPP) link are counted... IF there is an OSPF router on each end.
This is backed up by the fact that LabC, OSPF id 40.1, has four OSPF links. The top-facing link to the 30
network DOES count.. even though it has no OSPF router on the other end. It counts because it's not a serial link.
The requirement of having an OSPF router on the other end for an interface to count here, only applies
to serial links. And pertains to BOTH ends of the link being counted.
In LabC's case, we have one serial at left, being counted twice. One ethernet at top, being counted once. And
one serial at right only being counted once because LabD is not active with OSPF yet.
If this is correct, then we should see Lab C's 40.1 count go to 5 after LabD is set for OSPF....
LabD - all 4 routers have OSPF
show ip ospf database
OSPF Router with ID (172.16.50.1) (Process ID 103)
Router Link States (Area 0)
Link ID ADV Router Age Seq# Checksum Link count
172.16.10.1 172.16.10.1 785 0x80000002 0x0067cd 1
172.16.20.1 172.16.20.1 333 0x80000004 0x00a551 3
172.16.40.1 172.16.40.1 111 0x80000005 0x00013b 5
172.16.50.1 172.16.50.1 53 0x80000003 0x001023 3
Net Link States (Area 0)
Link ID ADV Router Age Seq# Checksum
172.16.10.1 172.16.10.1 785 0x80000001 0x00953d
and back to LabC.....
show ip ospf database
OSPF Router with ID (172.16.40.1) (Process ID 102)
Router Link States (Area 0)
Link ID ADV Router Age Seq# Checksum Link count
172.16.10.1 172.16.10.1 1174 0x80000002 0x0067cd 1
172.16.20.1 172.16.20.1 722 0x80000004 0x00a551 3
172.16.40.1 172.16.40.1 500 0x80000005 0x00013b 5
172.16.50.1 172.16.50.1 441 0x80000003 0x001023 3
Net Link States (Area 0)
Link ID ADV Router Age Seq# Checksum
172.16.10.1 172.16.10.1 1174 0x80000001 0x00953d
Looks good! The link count for each router makes sense if you count the serial interfaces twice (one for each end).
the OSPF databases now match across all 4 routers.
NOTE that this is a database of routers, identified by
router ID. It is not a topology that lists routers AND routes, like in
the "equivalent" eigrp command show eigrp topology
Note that the .30 network is NOT represented here.
LabA#
show ip ospf database
OSPF Router with ID (172.16.10.1) (Process ID 100)
Router Link States (Area 0)
Link ID ADV Router Age Seq# Checksum Link count
172.16.10.1 172.16.10.1 1138 0x80000002 0x0067cd 1
172.16.20.1 172.16.20.1 686 0x80000004 0x00a551 3
172.16.40.1 172.16.40.1 463 0x80000005 0x00013b 5
172.16.50.1 172.16.50.1 404 0x80000003 0x001023 3
Net Link States (Area 0)
Link ID ADV Router Age Seq# Checksum
172.16.10.1 172.16.10.1 1138 0x80000001 0x00953d
LabB#
show ip ospf database
OSPF Router with ID (172.16.20.1) (Process ID 101)
Router Link States (Area 0)
Link ID ADV Router Age Seq# Checksum Link count
172.16.10.1 172.16.10.1 1151 0x80000002 0x0067cd 1
172.16.20.1 172.16.20.1 699 0x80000004 0x00a551 3
172.16.40.1 172.16.40.1 476 0x80000005 0x00013b 5
172.16.50.1 172.16.50.1 417 0x80000003 0x001023 3
Net Link States (Area 0)
Link ID ADV Router Age Seq# Checksum
172.16.10.1 172.16.10.1 1151 0x80000001 0x00953d
LabC#
show ip ospf database
OSPF Router with ID (172.16.40.1) (Process ID 102)
Router Link States (Area 0)
Link ID ADV Router Age Seq# Checksum Link count
172.16.10.1 172.16.10.1 1174 0x80000002 0x0067cd 1
172.16.20.1 172.16.20.1 722 0x80000004 0x00a551 3
172.16.40.1 172.16.40.1 500 0x80000005 0x00013b 5
172.16.50.1 172.16.50.1 441 0x80000003 0x001023 3
Net Link States (Area 0)
Link ID ADV Router Age Seq# Checksum
172.16.10.1 172.16.10.1 1174 0x80000001 0x00953d
LabD#
show ip ospf database
OSPF Router with ID (172.16.50.1) (Process ID 103)
Router Link States (Area 0)
Link ID ADV Router Age Seq# Checksum Link count
172.16.10.1 172.16.10.1 785 0x80000002 0x0067cd 1
172.16.20.1 172.16.20.1 333 0x80000004 0x00a551 3
172.16.40.1 172.16.40.1 111 0x80000005 0x00013b 5
172.16.50.1 172.16.50.1 53 0x80000003 0x001023 3
Net Link States (Area 0)
Link ID ADV Router Age Seq# Checksum
172.16.10.1 172.16.10.1 785 0x80000001 0x00953d
Below is our routing tables with OSPF data. We do see the .30 network here.
Everyone can reach it:
LabA via LabB's 10.2
LabB via LabC's 20.2
LabC via direct connection
LabD via LabC's 40.1
LabA#
show ip route
172.16.0.0/16 is variably subnetted, 6 subnets, 2 masks
C 172.16.10.0/24 is directly connected, FastEthernet0/0
L 172.16.10.1/32 is directly connected, FastEthernet0/0
O 172.16.20.0/24 [110/65] via 172.16.10.2, 00:28:03, FastEthernet0/0
O 172.16.30.0/24 [110/66] via 172.16.10.2, 00:21:35, FastEthernet0/0
O 172.16.40.0/24 [110/129] via 172.16.10.2, 00:21:25, FastEthernet0/0
O 172.16.50.0/24 [110/130] via 172.16.10.2, 00:17:40, FastEthernet0/0
LabB#
show ip route
172.16.0.0/16 is variably subnetted, 7 subnets, 2 masks
C 172.16.10.0/24 is directly connected, FastEthernet0/0
L 172.16.10.2/32 is directly connected, FastEthernet0/0
C 172.16.20.0/24 is directly connected, Serial0/0/0
L 172.16.20.1/32 is directly connected, Serial0/0/0
O 172.16.30.0/24 [110/65] via 172.16.20.2, 00:27:04, Serial0/0/0
O 172.16.40.0/24 [110/128] via 172.16.20.2, 00:26:54, Serial0/0/0
O 172.16.50.0/24 [110/129] via 172.16.20.2, 00:23:09, Serial0/0/0
LabC#
show ip route
172.16.0.0/16 is variably subnetted, 8 subnets, 2 masks
O 172.16.10.0/24 [110/65] via 172.16.20.1, 00:27:52, Serial0/0/0
C 172.16.20.0/24 is directly connected, Serial0/0/0
L 172.16.20.2/32 is directly connected, Serial0/0/0
C 172.16.30.0/24 is directly connected, FastEthernet0/0
L 172.16.30.1/32 is directly connected, FastEthernet0/0
C 172.16.40.0/24 is directly connected, Serial0/0/1
L 172.16.40.1/32 is directly connected, Serial0/0/1
O 172.16.50.0/24 [110/65] via 172.16.40.2, 00:23:36, Serial0/0/1
LabD#
show ip route
172.16.0.0/16 is variably subnetted, 7 subnets, 2 masks
O 172.16.10.0/24 [110/129] via 172.16.40.1, 00:25:20, Serial0/0/0
O 172.16.20.0/24 [110/128] via 172.16.40.1, 00:25:20, Serial0/0/0
O 172.16.30.0/24 [110/65] via 172.16.40.1, 00:25:20, Serial0/0/0
C 172.16.40.0/24 is directly connected, Serial0/0/0
L 172.16.40.2/32 is directly connected, Serial0/0/0
C 172.16.50.0/24 is directly connected, FastEthernet0/0
L 172.16.50.1/32 is directly connected, FastEthernet0/0
moving on.......
9.5 - OSPF DR and BDR Elections
EachRouter(config)#
hostname X (A, B, or C)
EachRouter(config)#
line con 0
EachRouter(config-line)#
exec-timeout 0 0
A(config)#
int f0/0
A(config-if)#
ip addr 10.1.1.1 255.255.255.0
A(config-if)#
no shut
A(config)#
router ospf 12345
A(config-router)#
net 10.1.1.0 0.0.0.255 area 0
00:23:30: %OSPF-5-ADJCHG: Process 12345, Nbr 10.1.1.3 on FastEthernet0/0 from LOADING to FULL, Loading Done
00:23:30: %OSPF-5-ADJCHG: Process 12345, Nbr 10.1.1.2 on FastEthernet0/0 from LOADING to FULL, Loading Done
A#
show ip ospf int
note this output was generated AFTER all 3 routers set for OSPF
FastEthernet0/0 is up, line protocol is up
Internet address is 10.1.1.1/24, Area 0
Process ID 12345, Router ID 10.1.1.1, Network Type BROADCAST, Cost: 1
Transmit Delay is 1 sec, State DROTHER, Priority 1
Designated Router (ID) 10.1.1.3, Interface address 10.1.1.3
Backup Designated Router (ID) 10.1.1.2, Interface address 10.1.1.2
Timer intervals configured, Hello 10, Dead 40, Wait 40, Retransmit 5
Hello due in 00:00:04
Index 1/1, flood queue length 0
Next 0x0(0)/0x0(0)
Last flood scan length is 1, maximum is 1
Last flood scan time is 0 msec, maximum is 0 msec
Neighbor Count is 2, Adjacent neighbor count is 2
Adjacent with neighbor 10.1.1.3 (Designated Router)
Adjacent with neighbor 10.1.1.2 (Backup Designated Router)
Suppress hello for 0 neighbor(s)
A(config-if)#shut
A(config-if)#
%LINK-5-CHANGED: Interface FastEthernet0/0, changed state to administratively down
%LINEPROTO-5-UPDOWN: Line protocol on Interface FastEthernet0/0, changed state to down
00:40:28: %OSPF-5-ADJCHG: Process 12345, Nbr 10.1.1.2 on FastEthernet0/0 from FULL to DOWN, Neighbor Down: Interface down or detached
00:40:28: OSPF: Build router LSA for area 0, router ID 10.1.1.1, seq 0xffffffff80000003
00:40:28: %OSPF-5-ADJCHG: Process 12345, Nbr 10.1.1.3 on FastEthernet0/0 from FULL to DOWN, Neighbor Down: Interface down or detached
00:40:28: OSPF: Build router LSA for area 0, router ID 10.1.1.1, seq 0xffffffff80000004
00:40:28: OSPF: Build router LSA for area 0, router ID 10.1.1.1, seq 0xffffffff80000004
A(config-if)#no shut
A(config-if)#
%LINK-5-CHANGED: Interface FastEthernet0/0, changed state to up
%LINEPROTO-5-UPDOWN: Line protocol on Interface FastEthernet0/0, changed state to up
00:40:48: OSPF: Build router LSA for area 0, router ID 10.1.1.1, seq 0xffffffff80000004
00:41:27: OSPF: Backup seen Event before WAIT timer on FastEthernet0/0
00:41:27: OSPF: DR/BDR election on FastEthernet0/0
00:41:27: OSPF: Elect BDR 10.1.1.2
00:41:27: OSPF: Elect DR 10.1.1.3
00:41:27: DR: 10.1.1.3 (Id) BDR: 10.1.1.2 (Id)
00:41:27: OSPF: Send DBD to 10.1.1.3 on FastEthernet0/0 seq 0x5accb8e2 opt 0x00 flag 0x7 len 32
B(config)#
int f0/0
B(config-if)#
ip addr 10.1.1.2 255.255.255.0
B(config-if)#
no shut
B(config)#
router ospf 12345
B(config-router)#
net 10.1.1.0 0.0.0.255 area 0
00:23:29: %OSPF-5-ADJCHG: Process 12345, Nbr 10.1.1.3 on FastEthernet0/0 from LOADING to FULL, Loading Done
00:23:29: %OSPF-5-ADJCHG: Process 12345, Nbr 10.1.1.1 on FastEthernet0/0 from LOADING to FULL, Loading Done
B#
show ip ospf int
note this output was generated AFTER all 3 routers set for OSPF
FastEthernet0/0 is up, line protocol is up
Internet address is 10.1.1.2/24, Area 0
Process ID 12345, Router ID 10.1.1.2, Network Type BROADCAST, Cost: 1
Transmit Delay is 1 sec, State BDR, Priority 1
Designated Router (ID) 10.1.1.3, Interface address 10.1.1.3
Backup Designated Router (ID) 10.1.1.2, Interface address 10.1.1.2
Timer intervals configured, Hello 10, Dead 40, Wait 40, Retransmit 5
Hello due in 00:00:05
Index 1/1, flood queue length 0
Next 0x0(0)/0x0(0)
Last flood scan length is 1, maximum is 1
Last flood scan time is 0 msec, maximum is 0 msec
Neighbor Count is 2, Adjacent neighbor count is 2
Adjacent with neighbor 10.1.1.1
Adjacent with neighbor 10.1.1.3 (Designated Router)
Suppress hello for 0 neighbor(s)
B#debug ip ospf adj
OSPF adjacency events debugging is on
B#
00:39:21: OSPF: DR/BDR election on FastEthernet0/0
00:39:21: OSPF: Elect BDR 10.1.1.2
00:39:21: OSPF: Elect DR 10.1.1.3
00:39:21: DR: 10.1.1.3 (Id) BDR: 10.1.1.2 (Id)
00:41:01: %OSPF-5-ADJCHG: Process 12345, Nbr 10.1.1.1 on FastEthernet0/0 from FULL to DOWN, Neighbor Down: Dead timer expired
00:41:01: %OSPF-5-ADJCHG: Process 12345, Nbr 10.1.1.1 on FastEthernet0/0 from FULL to DOWN, Neighbor Down: Interface down or detached
00:41:01: OSPF: Build router LSA for area 0, router ID 10.1.1.2, seq 0xffffffff80000003
00:41:01: OSPF: DR/BDR election on FastEthernet0/0
00:41:01: OSPF: Elect BDR 10.1.1.2
00:41:01: OSPF: Elect DR 10.1.1.3
C(config)#
int f0/0
C(config-if)#
ip addr 10.1.1.3 255.255.255.0
C(config-if)#
no shut
C(config)#
router ospf 12345
C(config-router)#
net 10.1.1.0 0.0.0.255 area 0
00:23:27: %OSPF-5-ADJCHG: Process 12345, Nbr 10.1.1.1 on FastEthernet0/0 from LOADING to FULL, Loading Done
00:23:27: %OSPF-5-ADJCHG: Process 12345, Nbr 10.1.1.2 on FastEthernet0/0 from LOADING to FULL, Loading Done
C#
show ip ospf int
note this output was generated AFTER all 3 routers set for OSPF
FastEthernet0/0 is up, line protocol is up
Internet address is 10.1.1.3/24, Area 0
Process ID 12345, Router ID 10.1.1.3, Network Type BROADCAST, Cost: 1
Transmit Delay is 1 sec, State DR, Priority 1
Designated Router (ID) 10.1.1.3, Interface address 10.1.1.3
Backup Designated Router (ID) 10.1.1.2, Interface address 10.1.1.2
Timer intervals configured, Hello 10, Dead 40, Wait 40, Retransmit 5
Hello due in 00:00:00
Index 1/1, flood queue length 0
Next 0x0(0)/0x0(0)
Last flood scan length is 1, maximum is 1
Last flood scan time is 0 msec, maximum is 0 msec
Neighbor Count is 2, Adjacent neighbor count is 2
Adjacent with neighbor 10.1.1.1
Adjacent with neighbor 10.1.1.2 (Backup Designated Router)
Suppress hello for 0 neighbor(s)
C#debug ip ospf adj
OSPF adjacency events debugging is on
C#
00:39:19: OSPF: DR/BDR election on FastEthernet0/0
00:39:19: OSPF: Elect BDR 10.1.1.2
00:39:19: OSPF: Elect DR 10.1.1.3
00:39:19: DR: 10.1.1.3 (Id) BDR: 10.1.1.2 (Id)
00:40:59: %OSPF-5-ADJCHG: Process 12345, Nbr 10.1.1.1 on FastEthernet0/0 from FULL to DOWN, Neighbor Down: Dead timer expired
00:40:59: %OSPF-5-ADJCHG: Process 12345, Nbr 10.1.1.1 on FastEthernet0/0 from FULL to DOWN, Neighbor Down: Interface down or detached
00:40:59: OSPF: Build router LSA for area 0, router ID 10.1.1.3, seq 0xffffffff80000003
00:40:59: OSPF: Build net LSA for area 0, router ID 10.1.1.3, seq 0xffffffff80000003
00:40:59: OSPF: DR/BDR election on FastEthernet0/0
00:40:59: OSPF: Elect BDR 10.1.1.2
00:40:59: OSPF: Elect DR 10.1.1.3
DR and BDR automtically set based on higest IP address
Note our network type is BROADCAST because we're using ethernet interfaces...
it would be point-to-point if using a serial connection
we want to manually overide the priority of the router. ZERO priority means it wont participate in the election process
MAX priority of 255 means no other router can beat it for DR
We'll set the priority for router A to 3.
It will beome the DR only after we shut/no shut the interface router
AND
manually power on/off the other two routers
A(config)#
int f0/0
A(config-int)#
ip ospf priority 3
A(config-int)#
shut
A(config-int)#
no shut
A#
debug ip ospf adj
B#
debug ip ospf adj
00:05:50: OSPF: DR/BDR election on FastEthernet0/0
00:05:50: OSPF: Elect BDR 10.1.1.2
00:05:50: OSPF: Elect DR 10.1.1.1
00:05:50: OSPF: Elect BDR 10.1.1.2
00:05:50: OSPF: Elect DR 10.1.1.1
00:05:50: DR: 10.1.1.1 (Id) BDR: 10.1.1.2 (Id)
00:05:50: OSPF: Send DBD to 10.1.1.1 on FastEthernet0/0 seq 0x10164ebb opt 0x00 flag 0x7 len 32
00:05:50: OSPF: Build router LSA for area 0, router ID 10.1.1.2, seq 0xffffffff80000002
00:05:52: OSPF: Rcv DBD from 10.1.1.1 on FastEthernet0/0 seq 0x20368093 opt 0x00 flag 0x7 len 32 mtu 1500 state EXSTART
00:05:52: OSPF: First DBD and we are not SLAVE
00:05:55: OSPF: Send DBD to 10.1.1.1 on FastEthernet0/0 seq 0x10164ebb opt 0x00 flag 0x7 len 32
00:05:55: OSPF: Rcv DBD from 10.1.1.1 on FastEthernet0/0 seq 0x10164ebb opt 0x00 flag 0x2 len 112 mtu 1500 state EXSTART
00:05:55: OSPF: NBR Negotiation Done. We are the MASTER
00:05:55: OSPF: Send DBD to 10.1.1.1 on FastEthernet0/0 seq 0x10164ebc opt 0x00 flag 0x3 len 52
00:05:55: OSPF: Rcv DBD from 10.1.1.1 on FastEthernet0/0 seq 0x10164ebc opt 0x00 flag 0x0 len 32 mtu 1500 state EXCHANGE
00:05:55: OSPF: Send DBD to 10.1.1.1 on FastEthernet0/0 seq 0x10164ebd opt 0x00 flag 0x1 len 32
00:05:55: OSPF: Rcv DBD from 10.1.1.1 on FastEthernet0/0 seq 0x10164ebd opt 0x00 flag 0x0 len 32 mtu 1500 state EXCHANGE
00:05:55: Exchange Done with 10.1.1.1 on FastEthernet0/0
00:05:55: OSPF: Database request to 10.1.1.1
00:05:55: OSPF: sent LS REQ packet to 10.1.1.1, length 36
00:05:55: OSPF: Rcv DBD from 10.1.1.1 on FastEthernet0/0 seq 0x10164ebd opt 0x00 flag 0x0 len 32 mtu 1500 state LOADING
00:05:55: Synchronized with with 10.1.1.1 on FastEthernet0/0, state FULL
00:05:55: %OSPF-5-ADJCHG: Process 12345, Nbr 10.1.1.1 on FastEthernet0/0 from LOADING to FULL, Loading Done
00:05:55: OSPF: Build router LSA for area 0, router ID 10.1.1.2, seq 0xffffffff80000002
C#
debug ip ospf adj
00:06:13: OSPF: DR/BDR election on FastEthernet0/0
00:06:13: OSPF: Elect BDR 10.1.1.2
00:06:13: OSPF: Elect DR 10.1.1.1
00:06:13: DR: 10.1.1.1 (Id) BDR: 10.1.1.2 (Id)
00:06:13: OSPF: Send DBD to 10.1.1.1 on FastEthernet0/0 seq 0x1cc5536d opt 0x00 flag 0x7 len 32
00:06:13: OSPF: Send DBD to 10.1.1.2 on FastEthernet0/0 seq 0x3d51ca66 opt 0x00 flag 0x7 len 32
00:06:13: OSPF: Build router LSA for area 0, router ID 10.1.1.3, seq 0xffffffff80000002
00:06:17: OSPF: Rcv DBD from 10.1.1.1 on FastEthernet0/0 seq 0x6b532eec opt 0x00 flag 0x7 len 32 mtu 1500 state EXSTART
00:06:17: OSPF: First DBD and we are not SLAVE
00:06:17: OSPF: Rcv DBD from 10.1.1.2 on FastEthernet0/0 seq 0x783110f4 opt 0x00 flag 0x7 len 32 mtu 1500 state EXSTART
00:06:17: OSPF: First DBD and we are not SLAVE
00:06:18: OSPF: Send DBD to 10.1.1.2 on FastEthernet0/0 seq 0x3d51ca66 opt 0x00 flag 0x7 len 32
00:06:18: OSPF: Send DBD to 10.1.1.1 on FastEthernet0/0 seq 0x1cc5536d opt 0x00 flag 0x7 len 32
00:06:18: OSPF: Rcv DBD from 10.1.1.2 on FastEthernet0/0 seq 0x3d51ca66 opt 0x00 flag 0x2 len 132 mtu 1500 state EXSTART
00:06:18: OSPF: NBR Negotiation Done. We are the MASTER
00:06:18: OSPF: Send DBD to 10.1.1.2 on FastEthernet0/0 seq 0x3d51ca67 opt 0x00 flag 0x3 len 52
00:06:18: OSPF: Rcv DBD from 10.1.1.1 on FastEthernet0/0 seq 0x1cc5536d opt 0x00 flag 0x2 len 132 mtu 1500 state EXSTART
00:06:18: OSPF: NBR Negotiation Done. We are the MASTER
00:06:18: OSPF: Send DBD to 10.1.1.1 on FastEthernet0/0 seq 0x1cc5536e opt 0x00 flag 0x3 len 52
00:06:18: OSPF: Rcv DBD from 10.1.1.2 on FastEthernet0/0 seq 0x3d51ca67 opt 0x00 flag 0x0 len 32 mtu 1500 state EXCHANGE
00:06:18: OSPF: Send DBD to 10.1.1.2 on FastEthernet0/0 seq 0x3d51ca68 opt 0x00 flag 0x1 len 32
00:06:18: OSPF: Rcv DBD from 10.1.1.1 on FastEthernet0/0 seq 0x1cc5536e opt 0x00 flag 0x0 len 32 mtu 1500 state EXCHANGE
00:06:18: OSPF: Send DBD to 10.1.1.1 on FastEthernet0/0 seq 0x1cc5536f opt 0x00 flag 0x1 len 32
00:06:18: OSPF: Rcv DBD from 10.1.1.2 on FastEthernet0/0 seq 0x3d51ca68 opt 0x00 flag 0x0 len 32 mtu 1500 state EXCHANGE
00:06:18: Exchange Done with 10.1.1.2 on FastEthernet0/0
00:06:18: OSPF: Database request to 10.1.1.2
00:06:18: OSPF: sent LS REQ packet to 10.1.1.2, length 48
00:06:18: OSPF: Rcv DBD from 10.1.1.1 on FastEthernet0/0 seq 0x1cc5536f opt 0x00 flag 0x0 len 32 mtu 1500 state EXCHANGE
verify on all three routers
A#
show ip ospf interface f0/0
FastEthernet0/0 is up, line protocol is up
Internet address is 10.1.1.1/24, Area 0
Process ID 12345, Router ID 10.1.1.1, Network Type BROADCAST, Cost: 1
Transmit Delay is 1 sec, State DR, Priority 3
Designated Router (ID) 10.1.1.1, Interface address 10.1.1.1
Backup Designated Router (ID) 10.1.1.2, Interface address 10.1.1.2
Timer intervals configured, Hello 10, Dead 40, Wait 40, Retransmit 5
Hello due in 00:00:09
Index 1/1, flood queue length 0
Next 0x0(0)/0x0(0)
Last flood scan length is 1, maximum is 1
Last flood scan time is 0 msec, maximum is 0 msec
Neighbor Count is 2, Adjacent neighbor count is 2
Adjacent with neighbor 10.1.1.2 (Backup Designated Router)
Adjacent with neighbor 10.1.1.3
Suppress hello for 0 neighbor(s)
A#
show ip ospf neighbor
Neighbor ID Pri State Dead Time Address Interface
10.1.1.2 1 FULL/BDR 00:00:37 10.1.1.2 FastEthernet0/0
10.1.1.3 1 FULL/DROTHER 00:00:30 10.1.1.3 FastEthernet0/0
B#
show ip ospf interface f0/0
FastEthernet0/0 is up, line protocol is up
Internet address is 10.1.1.2/24, Area 0
Process ID 12345, Router ID 10.1.1.2, Network Type BROADCAST, Cost: 1
Transmit Delay is 1 sec, State BDR, Priority 1
Designated Router (ID) 10.1.1.1, Interface address 10.1.1.1
Backup Designated Router (ID) 10.1.1.2, Interface address 10.1.1.2
Timer intervals configured, Hello 10, Dead 40, Wait 40, Retransmit 5
Hello due in 00:00:08
Index 1/1, flood queue length 0
Next 0x0(0)/0x0(0)
Last flood scan length is 1, maximum is 1
Last flood scan time is 0 msec, maximum is 0 msec
Neighbor Count is 2, Adjacent neighbor count is 2
Adjacent with neighbor 10.1.1.1 (Designated Router)
Adjacent with neighbor 10.1.1.3
Suppress hello for 0 neighbor(s)
B#
show ip ospf neighbor
Neighbor ID Pri State Dead Time Address Interface
10.1.1.1 3 FULL/DR 00:00:35 10.1.1.1 FastEthernet0/0
10.1.1.3 1 FULL/DROTHER 00:00:31 10.1.1.3 FastEthernet0/0
C#
show ip ospf interface f0/0
FastEthernet0/0 is up, line protocol is up
Internet address is 10.1.1.3/24, Area 0
Process ID 12345, Router ID 10.1.1.3, Network Type BROADCAST, Cost: 1
Transmit Delay is 1 sec, State DROTHER, Priority 1
Designated Router (ID) 10.1.1.1, Interface address 10.1.1.1
Backup Designated Router (ID) 10.1.1.2, Interface address 10.1.1.2
Timer intervals configured, Hello 10, Dead 40, Wait 40, Retransmit 5
Hello due in 00:00:06
Index 1/1, flood queue length 0
Next 0x0(0)/0x0(0)
Last flood scan length is 1, maximum is 1
Last flood scan time is 0 msec, maximum is 0 msec
Neighbor Count is 2, Adjacent neighbor count is 2
Adjacent with neighbor 10.1.1.1 (Designated Router)
Adjacent with neighbor 10.1.1.2 (Backup Designated Router)
Suppress hello for 0 neighbor(s)
C#
show ip ospf neighbor/span>
Neighbor ID Pri State Dead Time Address Interface
10.1.1.1 3 FULL/DR 00:00:35 10.1.1.1 FastEthernet0/0
10.1.1.2 1 FULL/BDR 00:00:37 10.1.1.2 FastEthernet0/0
Router1 is the DR with priority 3
still need more work to understand the output of the defbu ospf adj
Chapter 9 Review Questions
1. There are three possible routes for a router to reach a destination network:
OSPF with a metric of 782
RIPv2 with a metric of 4
EIGRP with a composite metric of 20514560
Which route will be installed in the routing table?
EIGRP because it has the lowest Administrative Distance, and AD is always used before metric
ADs are:
ExternalEIGRP 170
RIP 120
OSPF 110
IGRP 100
EIGRP 90
Static 1
Connected 0
2. Which EIGRP information is held in RAM and maintained through the use of Hello and update packets?
Neighbor table
and
toplogy table
3. Describe the process identifier that is used to run OSPF on a router
The OSPF process id is only locally significant. A random number can be selected. But it's required in order to identify
a unique OSPF database instance. You can use the same, or a different number on each router, doesnt matter.
Any number can be used from 1 to 65,535. Process ID is supplied as an argument to the command router ospf
NOT to be confused with the area number which can be any number up to 4 billion. The area id identifies a logical grouping of routers.
area id is supplied as argument to the OSPF network id and mask command
Ex:
R1(config)#
router ospf 12345
R1(config-router)#
net 10.1.1.0 0.0.0.255 area 0
4. Where are EIGRP successor routes stored?
EIGRP succesor routers are stored in the routing table. The "succesor" is the successful or primary route.
The successor route is ALSO listed in the topology table,
The feasible successor is a BACKUP route and will ONLY be listed in the topology table, unless the successor route fails,
in which case the feasible successor would become the successor
Note that my EIGRP setup doesnt seem to folow this.
CTRL-F jump to "remotely connected via remote ingress ip address"
the book states that EIGRP is automatically load-balancing our two links from R1 to corp.. is this why there is no feasible successor here?
I did some research and found that in our case, we are not using a Feasible Successor. You CAN have two Successors with equal metric, in which case EIGRP will
automatically load-balance.
But I wanted to find out what a Feasible Successor actually looks like in the EIGRP topology table..
Kevin Wallace EIGRP article
Conclusion:
EIGRP topology table wouldnt specifically say "Feasible Successor", but you would know by two routes appearing, one with a lower metric.
In my topology we have two equal-metric links and they are both considered "Successors". EIGRP uses them equally (load-balanced)
Corp#
show ip eigrp toplogy
[cut]
P 172.16.10.0/24, 1 successors, FD is 28160
via 10.1.5.2 (28160/25600), FastEthernet0/0
P 192.168.10.0/24, 2 successors, FD is 2172416
via 10.1.3.2 (2172416/28160), Serial0/0/1
via 10.1.2.2 (2172416/28160), Serial0/0/0
P 192.168.20.0/24, 2 successors, FD is 2172416
via 10.1.3.2 (2172416/28160), Serial0/0/1
via 10.1.2.2 (2172416/28160), Serial0/0/0
P 192.168.30.0/24, 1 successors, FD is 2172416
via 10.1.4.2 (2172416/28160), Serial0/1/0
P 192.168.40.0/24, 1 successors, FD is 2172416
via 10.1.4.2 (2172416/28160), Serial0/1/0
5. Which command will display all the EIGRP feasible successor routes to a known router.
show ip eigrp topology
6. Find the configuration error. You type the following into your router, but dont see any routes in the routing table?
Router(config)#
router ospf 1
Router(config-router)#
network 10.0.0.0 255.0.0.0
wrong wildcard mask
instead, could have used
0.255.255.255
or
0.0.0.255
the point is we need to specify the first octet as "allowed" into our OSPF config with a 0 mask.
The remaining bits are 'dont care' bits aka 'wildcard' aka 255
7. Which three protocols support VLSM, summarization, and discontigous networking?
RIPv2
EIGRP
OSPF
all 3 build and mainting routing tables, provide classless routing which allows VLSM, summarization, and discontigous networks
RIPv1 and IGRP build/maintain routing tables, but dont offer classless routing
8. Which are true regarding OSPF areas?
the 'backbone' is area 0
if using other areas, they all must directly connect to area 0
9. Which two network types have a designated router and a backup designated router?
Broadcast
NBMA- Non broadcast multi access. Ex: Frame Relay
network types that DO NOT use DR/BDR:
point to point
broadcast multipoint
10. You need to configure a router with a distance-vector protocol that allows classless routing. Which to use?
EIGRP is considered 'advanced distance vector' (ripv2 wasnt an option)
11. You need the IP address of the devices with which the router has established an adjacency.
Also, the retransmit interval and the queue counts for the adjacent routers need to be checked. What command will display the required information?
show ip eigrp neighbors
WRONG: show ip eigrp adjacency - there is no such command.. the word 'adjacency' is only used with debug ip OSPF adjacency
here are the possible commands for show ip eigrp and debug ip eigrp
show ip eigrp ?
interfaces IP-EIGRP interfaces
neighbors IP-EIGRP neighbors
topology IP-EIGRP Topology Table
traffic IP-EIGRP Traffic Statistics
debug ip eigrp ?
summary IP-EIGRP summary route processing
12. You cant establish an adjacency relationship on a common ethernet link between two routers. Based on the output below, what is the cause of the problem?
RouterA#
Ethernet0/0 is up, line protocol is up
Internet Address 172.16.1.2/16, Area 0
Process ID 2, Router ID 172.126.1.2, Network Type BROADCAST, Cost: 10
Transmit Delay is 1 sec, State DR, Priority 1
Designated Router (ID) 172.16.1.2, interface address 172.16.1.1.
No backup designated router on this network
Timer intervals configured, Hello 5, Dead 20, Wait 20, Retransmit 5
Router B#
Internet Address 172.16.1.1/16, Area 0
Process ID 2, Router ID 172.126.1.1, Network Type BROADCAST, Cost: 10
Transmit Delay is 1 sec, State DR, Priority 1
Designated Router (ID) 172.16.1.1, interface address 172.16.1.2.
No backup designated router on this network
Timer intervals configured, Hello 10, Dead 40, Wait 40, Retransmit 5
mismatched timer intervals
OSPF default Hello is 10 and Dead is 40... RouterA was modified
13. Which is true regarding EIGRP successor routes?
Used in the routing table
also appears in the topolgy table
may (or may not) have a backup feasabile successor
14. Which type of OSPF network will elect a backup designated router?
broadcast multi-access
non-broadcast multiaccess
types of network that will NOT elect a BDR:
point to point and brodacast multipoint (hub/spoke topology)
15. Which two commands will place network 10.2.3.0/24 into area 0?
Router(config)#
router ospf 10
Router(config-router)#
network 10.2.3.0 0.0.0.255 area 0
16. With which network type will OSPF establish router adjacencies but not perform the DR/BDR election process?
Point to point
no election process occurs, there is never a DR on point to point
17. What are three reasons for creating OSPF in a heirarchical design?
decrease routing overhead
speed up convergence
confine stability to single areas of the network
18. What is the administrative distance of OSPF?
110
19.
no auto summary
the network is considered discontigous because we have two classful network subnetted (on the left and right),
seperated by a different classful address.
if auto summarization is taking place, the routers cant determine which side is which because both sides would be summarized as
Class B, 172.16.0.0, which isnt specific enough to distinguish between the sides.
20. IF routers in a single area are configured with the same priority value, what value does a router use for the OSPF router ID in the absence of a loopback interface?
The highest IP of any PHSYICAL interface.
Trick question. Highest IP of any LOGICAL interface is an option. And is correct IF you had logical interfaces, but the question
states that any "logical interfaces are absent".
At OSPF startup, the highest IP of *any* active interface on the router becomes the OSPF router ID. If you have loopback (logical) interfaces configured,
one of them (the largest IP) will *override* the phsyical interfaces and the loopback IP becomes the RID.
Reference for which loopback (if multiple) wins:
packetpushers.net
------------------------------------------------------------------------------
END CHAPTER 9
41 hours 2-14 thru 2-28-22
original total 184 hours
14 hours review 12-26 thru 12-28-22
review total hours 46
book page 502/822
184 + 46 = 230 hours * 60 = (13,800 min) / 500 pages =
avg 28 min/page (includes reading and exercises/labs + online research)
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1. What does the command
confreg 0x2142
provide?
bypass startup-config, to allow password reset
2. Which command will copy the IOS to a backup host on your network?
copy flash tftp
3. You are troubleshooting a connectivity problem in your corporate network and want to isolate the problem. You suspect that a router on the route to an unreachable
network is at fault. What IOS user exec command should you issue?
traceroute
note this is not a priviliged mode command; it can be run from user mode
note this is not a priviliged mode command; it can be run from user mode
4. You copy a configuration from a network host to a router's RAM. The configuration looks correct, yet it is no working at all. What could the problem be?
when you perform a copy from a network host to a router, the interfaces are automatically shut down and have to be manually enabled with no shutdown
5. A network administrator wants to upgrade the IOS of a router without removing the image currently installed. What command will display the amount of memory consumed by the
current IOS image and indicate whether there is enough room available to hold both the current and new images?
show flash
6. The corporate office sends you a new router to connect, but upon connecting the console cable, you see that there is already a configuration on the router.
What should be done before a new configuration is entered in the router?
erase NVRAM and restart the router
erase startup-config
reload
erase startup-config
reload
7. Which command loads a new version of the Cisco IOS into a router?
copy tftp flash
8. Which command will show you the IOS version running on your router?
show version
9. What should the configuration register value be after you successfully complete the password recovery procedure and return the router to normal operation?
0x2102
10. You save the configuration on a router with the
copy running-config startup-config
command and reboot the router. The router, however, comes up with a blank configuration. What can the problem be?
wrong config register causing you to bypass startup-confing in NVRAM
11. If you want to have more than one Telnet session open at the same time, what keystroke combination would you use?
CTRL+SHIFT+6, X
12. You are unsuccessful in telnetting into a remote device, but you could telnet to the router earlier, However, you can still ping the remote device.
What can the problem be?
access control list could be filtering telnet
OR
the VTY password may not be set on the target
OR
the VTY password may not be set on the target
13. What information is displayed by the
show hosts
command?
gives info on temporary DNS entries and permanent name-to-address mappings created using the ip host command
14. Name three commands that can be used to check LAN connectivity problems on a router?
trace
show interfaces
show ip route
show interfaces
show ip route
15. You telnet to a router and make your necessary changes; now you want to end the Telnet session. What command do you type in?
exit
16. You telnet into a remote device and type
debug ip rip
but no output from the
debug
command is seen. What could the problem be?
to see console messages through a telnet session, you must enter the command terminal monitor
17. Which command displays the configuration register setting?
show version
18. You need to gather the IP address of a remote switch that is located in Hawaii. What can you do to find the address?
show cdp neighbors detail
19. You have your laptop directly connected into a router's Ethernet port. Which are requirements for the
copy flash tftp
command to be successful?
have a TFTP server running on the laptop
laptop must have an IP on the same subnet as the router interface
give the IP address of the laptop when asked after entering the command
laptop must have an IP on the same subnet as the router interface
give the IP address of the laptop when asked after entering the command
20. The configuration register setting of 0x2102 provides what function to a router?
points to NVRAM for startup-configuration AND boot sequence
pg 374
before I begin to configure this network, I want to look closer at the HARDWARE
Todd mentions these routers:
2811 with four serial interfaces and switch module or wireless card
1841
while the book was published in 2011, both routers appear to be available in 2021 packet tracer, but both are considered legacy as of Feb 2022.
The 2811:
The 1841:
we're going to need to understand the MODULES. What are these?
a few examples:
NM-1E is a 1-port ethernet module
NM-1FE-TX is a fast ethernet module
NM-8A/s is an Eight Port Async/Sync Network Module
HWIC-2T is a 2-port serial WAN interface card
HWIC-AP-AG-B is a wireless card
What is an "NM module"? A network module is a software module that implements a specific function in a network stack, such as a data link interface, a transport protocol, or a network application.
What is a "HWIC module"? A high-speed WAN interface card
Here is a look inside a real 2811:
Back to the requirements for our lab- Todd says the 2811 'Corp' router needs a switch module and four serial interfaces. NOTE the book doesnt give specifics on how to create the topology in Packet Tracer.
Our Packet Tracer 2811 offers these modules:
The NM-ESW-16 appears to be the only 'switch module', so I will add that.
And the HWIC-2T is a 2-Port Serial High-Speed WAN Interface Card, providing 2 serial ports. I will add two of these.
next: R3, which needs to be a 2811 with a wirless card. I will add the HWIC-AP-AG-B:
The HWIC-AP-AG-B module is a High-Speed WAN Interface Card providing integrated Access Point
functionality in the Cisco 1800 (Modular), Cisco 2800, and Cisco 3800 Integrated Services Routers.
It supports Single Band 802.11b/g or Dual Band 802.11a/b/g radios.
our router hardware is in place:
and here is where we need to end up
Next we need to figure out how to connect the server farm to the switch card on R1:
if I use the auto-select cable, I get a copper crossover cable connecting at fa0/0 on the router.
Per the diagram fa0/0 should connect to R3. I need to connect the servers to the switch card on R1.
Instead of using the auto-select cable, I'll try a straight-through cable.
Success. While the auto-select cable did not give me an option as to what port it will connect to, I did get the option when manually applying the straight-through cable. Instead of connecting to F0/0 which would require a crossover-cable(computer to router), I will connect to the integrated switch at port F1/0, then connect the other two servers to F1/1 and F1/2, respectively.
Also worth noting: the Physical Device diagrams in Packet Tracer do not show cables plugged into the ports. We are relying on the labels on the logical diagram to see which cables are plugged into which ports... As far as how we can tell what is connected from within the CLI.. I dont know right now.
Now I will connect the other routers. Here is the chart specifiying what interfaces should be used:
| Router | Network Address | Interface | Address |
|---|---|---|---|
| CORP | 10.1.1.0 | Vlan1 (switch card) | 10.1.1.1 |
| 10.1.2.0 | S0/0/0 | 10.1.2.1 | |
| 10.1.3.0 | S0/0/1 (DCE) | 10.1.3.1 | |
| 10.1.4.0 | S0/1/0 | 10.1.4.1 | |
| 10.1.5.0 | F0/0 | 10.1.5.1 | |
| R1 | 10.1.2.0 | S0/0/0 (DCE) | 10.1.2.2 |
| 10.1.3.0 | S0/0/1 | 10.1.3.2 | |
| 192.168.10.0 | F0/0 | 192.168.10.1 | |
| 192.168.20.0 | F0/1 | 192.168.20.1 | |
| R2 | 10.1.4.0 | S0/0/0 (DCE) | 10.1.4.2 |
| 192.168.30.0 | F0/0 | 192.168.30.1 | |
| 192.168.40.0 | F0/0 | 192.168.40.1 | |
| R3 | 10.1.5.0 | F0/0 | 10.1.5.2 |
| 172.16.10.0 | Dot11Radio0/0/0 | 172.16.10.1 |
PROBLEM
The R1 router doesnt appear to have any serial interfaces
I will add an HWIC-2T card to both R1 and R2 since the diagram calls for serial interfaces.
The HWIC-2T is a Cisco 2-Port Serial High-Speed WAN Interface Card, providing 2 serial ports.
PROBLEM
My Corp router is not showing those interfaces:
Solution
the placement of the cards on the router determines which interface numbers will be available.
In this case, it seems the interfaces start from the bottom right corner and increase on each slot moving clockwise. I found this out by filling all four slots on my router
which led to all interfaces being available. I then ran a card in each slot individually to isolate which interface numbers correspond to each slot:
Interestingly, while the physical slots seem to follow a 'clockwise' pattern, the list of available slots in the logical diagram does not;
We get an output of interfaces corresponding to slot 2, then 3, 1, and 4. This is a 'bottom to top' then 'left to right' pattern. Tricky.
Having said all that... I will run cards in slots 1 and 2 for this lab since we only need interfaces S0/0/0, S0/0/1, S0/1/0
The Router topology:
I'm not clear on the connections from R1 and R2 to the clients.. I assume there are switches involved.
For now I will follow the next steps in the book which are to configure the corp router as follows:
Router(config)#
hostname Corp
Corp(config)# enable secret todd
Corp(config)# interface vlan 1
Corp(config-if)# description Switch Card to Core Network
Corp(config-if)# ip address 10.1.1.1 255.255.255.0
Corp(config-if)# no shut
----------------------------------------------------------------------------------------------------------------
Corp(config-if)# int f1/0
Corp(config-if)# description Switch Port connection to WWW Server
Corp(config-if)# no shutdown
Corp(config-if)# int f1/1
Corp(config-if)# description Switch Port connection to Email Server
Corp(config-if)# no shutdown
Corp(config-if)# int f1/2
Corp(config-if)# description Switch Port connection to DNS Server
Corp(config-if)# no shutdown
----------------------------------------------------------------------------------------------------------------
Corp(config-if)# int s0/0/0
Corp(config-if)# description 1st Connection to R1
Corp(config-if)# ip address 10.1.2.1 255.255.255.0
Corp(config-if)# no shut
Corp(config-if)# int s0/0/1
Corp(config-if)# description 2nd Connection to R1
Corp(config-if)# ip address 10.1.3.1 255.255.255.0
Corp(config-if)# no shut
Corp(config-if)# int s0/1/0
Corp(config-if)# description Connection to R2
Corp(config-if)# ip address 10.1.4.1 255.255.255.0
Corp(config-if)# no shut
Corp(config-if)# int fa0/0
Corp(config-if)# description Connection to R3
Corp(config-if)# ip address 10.1.5.1 255.255.255.0
Corp(config-if)# no shut
----------------------------------------------------------------------------------------------------------------
Corp(config-if)# line con 0
Corp(config-if)# password console
Corp(config-if)# login
Corp(config-if)# logging synchro
Corp(config-if)# exec-timeout 0 0
----------------------------------------------------------------------------------------------------------------
Corp(config-if)# line aux 0
Corp(config-if)# password aux
Corp(config-if)# login
Corp(config-if)# exit
----------------------------------------------------------------------------------------------------------------
Corp(config)# line vty ?
<1-15>Last Line number
Corp(config)# line vty 0 15
Corp(config-if)# password telnet
Corp(config-if)# login
Corp(config-if)# exit
----------------------------------------------------------------------------------------------------------------
Corp(config)# no ip domain lookup
Corp(config)# banner motd # This is my Corp 2811 ISR Router #
Ctrl + Z
%SYS-5-CONFIG_I: Configured from console by console
(Ctrl-Z: When in a config mode, ends the config mode and returns you to privileged EXEC mode.... same as typing exit(?))
Corp# copy run start
Corp# show ip int br
Corp# show run
-----------------------------------------------------------------------------------------------------------------------
Corp(config)# enable secret todd
Corp(config)# interface vlan 1
Corp(config-if)# description Switch Card to Core Network
Corp(config-if)# ip address 10.1.1.1 255.255.255.0
Corp(config-if)# no shut
----------------------------------------------------------------------------------------------------------------
Corp(config-if)# int f1/0
Corp(config-if)# description Switch Port connection to WWW Server
Corp(config-if)# no shutdown
Corp(config-if)# int f1/1
Corp(config-if)# description Switch Port connection to Email Server
Corp(config-if)# no shutdown
Corp(config-if)# int f1/2
Corp(config-if)# description Switch Port connection to DNS Server
Corp(config-if)# no shutdown
----------------------------------------------------------------------------------------------------------------
Corp(config-if)# int s0/0/0
Corp(config-if)# description 1st Connection to R1
Corp(config-if)# ip address 10.1.2.1 255.255.255.0
Corp(config-if)# no shut
Corp(config-if)# int s0/0/1
Corp(config-if)# description 2nd Connection to R1
Corp(config-if)# ip address 10.1.3.1 255.255.255.0
Corp(config-if)# no shut
Corp(config-if)# int s0/1/0
Corp(config-if)# description Connection to R2
Corp(config-if)# ip address 10.1.4.1 255.255.255.0
Corp(config-if)# no shut
Corp(config-if)# int fa0/0
Corp(config-if)# description Connection to R3
Corp(config-if)# ip address 10.1.5.1 255.255.255.0
Corp(config-if)# no shut
----------------------------------------------------------------------------------------------------------------
Corp(config-if)# line con 0
Corp(config-if)# password console
Corp(config-if)# login
Corp(config-if)# logging synchro
Corp(config-if)# exec-timeout 0 0
----------------------------------------------------------------------------------------------------------------
Corp(config-if)# line aux 0
Corp(config-if)# password aux
Corp(config-if)# login
Corp(config-if)# exit
----------------------------------------------------------------------------------------------------------------
Corp(config)# line vty ?
<1-15>Last Line number
Corp(config)# line vty 0 15
Corp(config-if)# password telnet
Corp(config-if)# login
Corp(config-if)# exit
----------------------------------------------------------------------------------------------------------------
Corp(config)# no ip domain lookup
Corp(config)# banner motd # This is my Corp 2811 ISR Router #
Ctrl + Z
%SYS-5-CONFIG_I: Configured from console by console
(Ctrl-Z: When in a config mode, ends the config mode and returns you to privileged EXEC mode.... same as typing exit(?))
Corp# copy run start
Destination filename [startup-config]?
Building configuration...
[OK]
----------------------------------------------------------------------------------------------------------------
Corp# show ip int br
Interface IP-Address OK? Method Status Protocol
FastEthernet0/0 10.1.5.1 YES manual up down
FastEthernet0/1 unassigned YES unset administratively down down
Serial0/0/0 10.1.2.1 YES manual down down
Serial0/0/1 10.1.3.1 YES manual down down
Serial0/1/0 10.1.4.1 YES manual down down
Serial0/1/1 unassigned YES unset administratively down down
FastEthernet1/0 unassigned YES unset up up
FastEthernet1/1 unassigned YES unset up up
FastEthernet1/2 unassigned YES unset up up
FastEthernet1/3 unassigned YES unset administratively down down
FastEthernet1/4 unassigned YES unset administratively down down
FastEthernet1/5 unassigned YES unset administratively down down
FastEthernet1/6 unassigned YES unset administratively down down
FastEthernet1/7 unassigned YES unset administratively down down
FastEthernet1/8 unassigned YES unset administratively down down
FastEthernet1/9 unassigned YES unset administratively down down
FastEthernet1/10 unassigned YES unset administratively down down
FastEthernet1/11 unassigned YES unset administratively down down
FastEthernet1/12 unassigned YES unset administratively down down
FastEthernet1/13 unassigned YES unset administratively down down
FastEthernet1/14 unassigned YES unset administratively down down
FastEthernet1/15 unassigned YES unset administratively down down
Vlan1 10.1.1.1 YES manual up up
----------------------------------------------------------------------------------------------------------------
Corp# show run
Building configuration...
Current configuration : 2073 bytes
!
version 15.1
no service timestamps log datetime msec
no service timestamps debug datetime msec
no service password-encryption
!
hostname Corp
!
!
!
enable secret 5 $1$mERr$V5ujdIM9bTB/I.ipB0gkJ0
!
!
!
!
!
!
no ip cef
no ipv6 cef
!
!
!
!
license udi pid CISCO2811/K9 sn FTX1017U440-
!
!
!
!
!
!
!
!
!
no ip domain-lookup
!
!
spanning-tree mode pvst
!
!
!
!
!
!
interface FastEthernet0/0
description connection to R3
ip address 10.1.5.1 255.255.255.0
duplex auto
speed auto
!
interface FastEthernet0/1
no ip address
duplex auto
speed auto
shutdown
!
interface Serial0/0/0
description 1st connection to R1
ip address 10.1.2.1 255.255.255.0
clock rate 2000000
!
interface Serial0/0/1
description 2nd connection to R1
ip address 10.1.3.1 255.255.255.0
clock rate 2000000
!
interface Serial0/1/0
description connection to R2
ip address 10.1.4.1 255.255.255.0
!
interface Serial0/1/1
no ip address
clock rate 2000000
shutdown
!
interface FastEthernet1/0
description switch port connection to WWW Server
!
interface FastEthernet1/1
description switch port connection to Email Server
!
interface FastEthernet1/2
description switch port connection to DNS Server
!
interface FastEthernet1/3
shutdown
!
interface FastEthernet1/4
shutdown
!
interface FastEthernet1/5
shutdown
!
interface FastEthernet1/6
shutdown
!
interface FastEthernet1/7
shutdown
!
interface FastEthernet1/8
shutdown
!
interface FastEthernet1/9
shutdown
!
interface FastEthernet1/10
shutdown
!
interface FastEthernet1/11
shutdown
!
interface FastEthernet1/12
shutdown
!
interface FastEthernet1/13
shutdown
!
interface FastEthernet1/14
shutdown
!
interface FastEthernet1/15
shutdown
!
interface Vlan1
description Switch Card to Core Network
ip address 10.1.1.1 255.255.255.0
!
ip classless
!
ip flow-export version 9
!
!
!
banner motd ^C This is my Corp 2811 ISR Router ^C
!
!
!
!
!
line con 0
exec-timeout 0 0
password console
logging synchronous
login
!
line aux 0
password aux
login
!
line vty 0 4
password telnet
login
line vty 5 15
password telnet
login
!
!
!
end
-----------------------------------------------------------------------------------------------------------------------
more configurations:
R1
Router(config)# hostname R1
R1(config)# enable secret todd
R1(config)# int s0/0/0
R1(config-if)# ip address 10.1.2.2 255.255.255.0
R1(config-if)# Decription 1st connection to corp router
R1(config-if)# no shut
-----------------------------------------------------------------------------------------------
R1(config-if)# int s0/0/1
R1(config-if)# ip address 10.1.3.2 255.255.255.0
R1(config-if)# Decription 2nd connection to corp router
R1(config-if)# no shut
-----------------------------------------------------------------------------------------------
R1(config-if)# int f0/0
R1(config-if)# ip address 192.168.10.1 255.255.255.0
R1(config-if)# Decription connection to finance
R1(config-if)# no shut
-----------------------------------------------------------------------------------------------
R1(config-if)# int f0/1
R1(config-if)# ip address 192.168.20.1 255.255.255.0
R1(config-if)# Decription connection to marketing
R1(config-if)# no shut
R1(config-if)# exit -----------------------------------------------------------------------------------------------
R1(config)# line con 0
R1(config-line)# password console
R1(config-line)# login
R1(config-line)# logging synchronous
R1(config-line)# exec-timeout 0 0
-----------------------------------------------------------------------------------------------
R1(config-line)# line aux 0
R1(config-line)# password aux
R1(config-line)# login
R1(config-line)# exit -----------------------------------------------------------------------------------------------
R1(config)# line vty 0 ?
<0-15> Last Line number
R1(config)# line vty 0 807
R1(config-line)# password telnet
R1(config-line)# login
R1(config-line)# banner motd # This is my R1 Router #
R1(config-line)# exit -----------------------------------------------------------------------------------------------
R1(config)# no ip domain-lookup
R1(config)# exit
R1# copy run start
Router(config)# hostname R1
R1(config)# enable secret todd
R1(config)# int s0/0/0
R1(config-if)# ip address 10.1.2.2 255.255.255.0
R1(config-if)# Decription 1st connection to corp router
R1(config-if)# no shut
-----------------------------------------------------------------------------------------------
R1(config-if)# int s0/0/1
R1(config-if)# ip address 10.1.3.2 255.255.255.0
R1(config-if)# Decription 2nd connection to corp router
R1(config-if)# no shut
-----------------------------------------------------------------------------------------------
R1(config-if)# int f0/0
R1(config-if)# ip address 192.168.10.1 255.255.255.0
R1(config-if)# Decription connection to finance
R1(config-if)# no shut
-----------------------------------------------------------------------------------------------
R1(config-if)# int f0/1
R1(config-if)# ip address 192.168.20.1 255.255.255.0
R1(config-if)# Decription connection to marketing
R1(config-if)# no shut
R1(config-if)# exit -----------------------------------------------------------------------------------------------
R1(config)# line con 0
R1(config-line)# password console
R1(config-line)# login
R1(config-line)# logging synchronous
R1(config-line)# exec-timeout 0 0
-----------------------------------------------------------------------------------------------
R1(config-line)# line aux 0
R1(config-line)# password aux
R1(config-line)# login
R1(config-line)# exit -----------------------------------------------------------------------------------------------
R1(config)# line vty 0 ?
<0-15> Last Line number
R1(config)# line vty 0 807
R1(config-line)# password telnet
R1(config-line)# login
R1(config-line)# banner motd # This is my R1 Router #
R1(config-line)# exit -----------------------------------------------------------------------------------------------
R1(config)# no ip domain-lookup
R1(config)# exit
R1# copy run start
R2
Router(config)# hostname R2
R2(config)# enable secret todd
R2(config)# int s0/0/0
R2(config-if)# ip address 10.1.4.2 255.255.255.0
R2(config-if)# description connection to corp router
R2(config-if)# no shut
-----------------------------------------------------------------------------------------------
R2(config-if)# int f0/0
R2(config-if)# ip address 192.168.30.1 255.255.255.0
R2(config-if)# description connection to sales PC
R2(config-if)# no shut
-----------------------------------------------------------------------------------------------
R2(config-if)# int f0/1
R2(config-if)# ip address 192.168.40.1 255.255.255.0
R2(config-if)# description connection to HR pc
R2(config-if)# no shut
-----------------------------------------------------------------------------------------------
R2(config-if)# line con 0
R2(config-line)# password console
R2(config-line)# login
R2(config-line)# logging synchronous
R2(config-line)# exec-timeout 0 0
-----------------------------------------------------------------------------------------------
R2(config-line)# line aux 0
R2(config-line)# password aux
R2(config-line)# login
R2(config-line)# exit
-----------------------------------------------------------------------------------------------
R2(config)# line vty 0 ?
<0-15> Last Line number
R2(config)# line vty 0 807
R2(config-line)# password telnet
R2(config-line)# login
R2(config-line)# banner motd # This is my R1 Router #
R2(config-line)# exit
-----------------------------------------------------------------------------------------------
R2(config)# no ip domain-lookup
R2(config)# exit
R2# copy run start
Router(config)# hostname R2
R2(config)# enable secret todd
R2(config)# int s0/0/0
R2(config-if)# ip address 10.1.4.2 255.255.255.0
R2(config-if)# description connection to corp router
R2(config-if)# no shut
-----------------------------------------------------------------------------------------------
R2(config-if)# int f0/0
R2(config-if)# ip address 192.168.30.1 255.255.255.0
R2(config-if)# description connection to sales PC
R2(config-if)# no shut
-----------------------------------------------------------------------------------------------
R2(config-if)# int f0/1
R2(config-if)# ip address 192.168.40.1 255.255.255.0
R2(config-if)# description connection to HR pc
R2(config-if)# no shut
-----------------------------------------------------------------------------------------------
R2(config-if)# line con 0
R2(config-line)# password console
R2(config-line)# login
R2(config-line)# logging synchronous
R2(config-line)# exec-timeout 0 0
-----------------------------------------------------------------------------------------------
R2(config-line)# line aux 0
R2(config-line)# password aux
R2(config-line)# login
R2(config-line)# exit
-----------------------------------------------------------------------------------------------
R2(config)# line vty 0 ?
<0-15> Last Line number
R2(config)# line vty 0 807
R2(config-line)# password telnet
R2(config-line)# login
R2(config-line)# banner motd # This is my R1 Router #
R2(config-line)# exit
-----------------------------------------------------------------------------------------------
R2(config)# no ip domain-lookup
R2(config)# exit
R2# copy run start
R3
Router(config)# hostname R3
R3(config)# enable secret todd
R3(config)# int f0/0
R3(config-if)# ip address 10.1.5.2 255.255.255.0
R3(config-if)# description connection to corp router
R3(config-if)# no shut
-----------------------------------------------------------------------------------------------
R3(config-if)# int dot11radio0/0/0
R3(config-if)# ip address 172.16.10.1 255.255.255.0
R3(config-if)# description WLAN for mobile user
R3(config-if)# no shut
R3(config-if)# ssid ADMIN
stuck here 2-5-22-- packet tracer isnt taking me into the config-if-ssid prompt
R3(config-if-ssid)# guest-mode
R3(config-if-ssid)# authentication open
R3(config-if-ssid)# ingrastructure-ssid
R3(config-if-ssid)# exit
-----------------------------------------------------------------------------------------------
R3(config-if)# line con 0
R3(config-line)# password console
R3(config-line)# login
R3(config-line)# logging synchronous
R3(config-line)# exec-timeout 0 0
-----------------------------------------------------------------------------------------------
R3(config-line)# line aux 0
R3(config-line)# password aux
R3(config-line)# login
R3(config-line)# exit
-----------------------------------------------------------------------------------------------
R3(config)# line vty 0 ?
<0-15> Last Line number
R3(config)# line vty 0 807
R3(config-line)# password telnet
R3(config-line)# login
R3(config-line)# banner motd # This is my R1 Router #
R3(config-line)# exit
-----------------------------------------------------------------------------------------------
R3(config)# no ip domain-lookup
R3(config)# exit
R3# copy run start
Router(config)# hostname R3
R3(config)# enable secret todd
R3(config)# int f0/0
R3(config-if)# ip address 10.1.5.2 255.255.255.0
R3(config-if)# description connection to corp router
R3(config-if)# no shut
-----------------------------------------------------------------------------------------------
R3(config-if)# int dot11radio0/0/0
R3(config-if)# ip address 172.16.10.1 255.255.255.0
R3(config-if)# description WLAN for mobile user
R3(config-if)# no shut
R3(config-if)# ssid ADMIN
stuck here 2-5-22-- packet tracer isnt taking me into the config-if-ssid prompt
R3(config-if-ssid)# guest-mode
R3(config-if-ssid)# authentication open
R3(config-if-ssid)# ingrastructure-ssid
R3(config-if-ssid)# exit
-----------------------------------------------------------------------------------------------
R3(config-if)# line con 0
R3(config-line)# password console
R3(config-line)# login
R3(config-line)# logging synchronous
R3(config-line)# exec-timeout 0 0
-----------------------------------------------------------------------------------------------
R3(config-line)# line aux 0
R3(config-line)# password aux
R3(config-line)# login
R3(config-line)# exit
-----------------------------------------------------------------------------------------------
R3(config)# line vty 0 ?
<0-15> Last Line number
R3(config)# line vty 0 807
R3(config-line)# password telnet
R3(config-line)# login
R3(config-line)# banner motd # This is my R1 Router #
R3(config-line)# exit
-----------------------------------------------------------------------------------------------
R3(config)# no ip domain-lookup
R3(config)# exit
R3# copy run start
PROBLEM
i cant get into conf-if-ssid prompt
R3(config-if)# ssid ADMIN
%LINK-5-CHANGED: Interface Dot11Radio0/0/0, changed state to administratively down
%LINEPROTO-5-UPDOWN: Line protocol on Interface Dot11Radio0/0/0, changed state to down
%LINK-5-CHANGED: Interface Dot11Radio0/0/0, changed state to up
%LINEPROTO-5-UPDOWN: Line protocol on Interface Dot11Radio0/0/0, changed state to up
R3(config-if)#
research led me to this thread, which is a dead end:
further research led me here:
R3(config)# global config mode
R3(config)# dot11 ssid ADMIN
creates an SSID or lets you config an existing SSID
R3(config-ssid)# guest-mode
R3(config-ssid)#
%LINK-5-CHANGED: Interface Dot11Radio0/0/0, changed state to administratively down
%LINEPROTO-5-UPDOWN: Line protocol on Interface Dot11Radio0/0/0, changed state to down
%LINK-5-CHANGED: Interface Dot11Radio0/0/0, changed state to up
%LINEPROTO-5-UPDOWN: Line protocol on Interface Dot11Radio0/0/0, changed state to up
R3(config-ssid)# authentication open
R3(config-ssid)#
%LINK-5-CHANGED: Interface Dot11Radio0/0/0, changed state to administratively down
%LINEPROTO-5-UPDOWN: Line protocol on Interface Dot11Radio0/0/0, changed state to down
%LINK-5-CHANGED: Interface Dot11Radio0/0/0, changed state to up
%LINEPROTO-5-UPDOWN: Line protocol on Interface Dot11Radio0/0/0, changed state to up
R3(config-ssid)# infrastructure-ssid
R3(config-ssid)#infrastructure-ssid
^
% Invalid input detected at '^' marker.
this command given by the book doesnt appear to be valid
R3(config-ssid)# ?
authentication authentication method
exit Exit from ssid sub mode
guest-mode guest ssid
no Negate a command or set it's defaults
wpa-psk Configure Wi-Fi Protected Access pre-shared key
back into the interface to see what the options are
R3(config-ssid)# int dot110/0/0
R3(config-if)# ?
arp Set arp type (arpa, probe, snap) or timeout or log options
bandwidth Set bandwidth informational parameter
cdp CDP interface subcommands
crypto Encryption/Decryption commands
delay Specify interface throughput delay
description Interface specific description
encryption Configure dot11 encryption parameters
exit Exit from interface configuration mode
fair-queue Enable Fair Queuing on an Interface
hold-queue Set hold queue depth
ip Interface Internet Protocol config commands
mac-address Manually set interface MAC address
mtu Set the interface Maximum Transmission Unit (MTU)
no Negate a command or set its defaults
priority-group Assign a priority group to an interface
service-policy Configure QoS Service Policy
shutdown Shutdown the selected interface
speed Set allowed radio bit rates
ssid Configure radio service set parameters
tx-ring-limit Configure PA level transmit ring limit
The infrastructure command may be expendable in this case... to be determined
here is our configuration for R3
R3# show run
R3# show run
Building configuration...
Current configuration : 1682 bytes
!
version 15.1
no service timestamps log datetime msec
no service timestamps debug datetime msec
no service password-encryption
!
hostname R3
!
!
!
enable secret 5 $1$mERr$V5ujdIM9bTB/I.ipB0gkJ0
!
!
ip dhcp excluded-address 172.16.10.1 172.16.10.10
!
ip dhcp pool Admin
network 172.16.10.0 255.255.255.0
default-router 172.16.10.1
!
dot11 ssid ADMIN
authentication open
guest-mode
!
dot11 ssid ADMIN2
authentication open
guest-mode
!
!
!
ip cef
no ipv6 cef
!
!
!
!
license udi pid CISCO2811/K9 sn FTX1017RE40-
!
!
!
!
!
!
!
!
!
no ip domain-lookup
ip name-server 172.16.10.4
!
!
spanning-tree mode pvst
!
!
!
!
!
!
interface FastEthernet0/0
description connection to corp router
ip address 10.1.5.2 255.255.255.0
duplex auto
speed auto
!
interface FastEthernet0/1
no ip address
duplex auto
speed auto
shutdown
!
interface Dot11Radio0/0/0
description WAN for mobile
ip address 172.16.10.1 255.255.255.0
speed 12.0 18.0 24.0 36.0 48.0 54.0 6.0 9.0 basic-1.0 basic-11.0 basic-2.0 basic-5.5
ssid ADMIN2
!
interface Dot11Radio0/0/1
no ip address
speed 18.0 36.0 48.0 54.0 9.0 basic-12.0 basic-24.0 basic-6.0
!
interface Serial0/1/0
no ip address
clock rate 2000000
!
interface Serial0/1/1
no ip address
clock rate 2000000
!
interface Vlan1
no ip address
shutdown
!
router rip
version 2
network 10.0.0.0
network 172.16.0.0
!
ip classless
ip route 0.0.0.0 0.0.0.0 10.1.5.1
!
ip flow-export version 9
!
!
!
banner motd ^C this is R3 $
this is R3 ^C
!
!
!
!
!
line con 0
exec-timeout 0 0
password console
logging synchronous
login
!
line aux 0
password aux
login
!
line vty 0 4
password telnet
login
line vty 5 15
password telnet
login
!
!
!
end
to summarize...
the book is a little off here.
-----------------------------------------------------------------------------------------------
R3(config-if)# int dot11radio0/0/0
R3(config-if)# ip address 172.16.10.1 255.255.255.0
R3(config-if)# description WLAN for mobile user
R3(config-if)# no shut
at this point we have created a wireless interface with an IP address but no SSID exists on this router
interface Dot11Radio0/0/0
description test router 2
ip address 172.16.10.1 255.255.255.0
speed 12.0 18.0 24.0 36.0 48.0 54.0 6.0 9.0 basic-1.0 basic-11.0 basic-2.0 basic-5.5
Trying to use the command "ssid ADMIN" doesnt work here. The below commands are invalid here:
R3(config-if)# ssid ADMIN
R3(config-if-ssid)# guest-mode
R3(config-if-ssid)# authentication open
R3(config-if-ssid)# ingrastructure-ssid
R3(config-if-ssid)# exit
-----------------------------------------------------------------------------------------------
We need to drop out of config-if, back to config, and enter SSID config mode
-----------------------------------------------------------------------------------------------
R3(config-if)# exit
R3(config)# dot11 ssid ADMIN2 creates an ssid named ADMIN2, and puts us into SSID config mode
R3(config-ssid)# guest-mode
R3(config-ssid)# authentication open
then out of config-ssid and back to interface config
R3(config-ssid)# exit
R3(config) int dot11r0/0/0
R3(config-if) ?
arp Set arp type (arpa, probe, snap) or timeout or log options
bandwidth Set bandwidth informational parameter
cdp CDP interface subcommands
crypto Encryption/Decryption commands
delay Specify interface throughput delay
description Interface specific description
encryption Configure dot11 encryption parameters
exit Exit from interface configuration mode
fair-queue Enable Fair Queuing on an Interface
hold-queue Set hold queue depth
ip Interface Internet Protocol config commands
mac-address Manually set interface MAC address
mtu Set the interface Maximum Transmission Unit (MTU)
no Negate a command or set its defaults
priority-group Assign a priority group to an interface
service-policy Configure QoS Service Policy
shutdown Shutdown the selected interface
speed Set allowed radio bit rates
ssid Configure radio service set parameters
tx-ring-limit Configure PA level transmit ring limit
we have the option for ssid
R3(config-if) ssid ADMIN2
%LINK-5-CHANGED: Interface Dot11Radio0/0/0, changed state to administratively down
%LINEPROTO-5-UPDOWN: Line protocol on Interface Dot11Radio0/0/0, changed state to down
%LINK-5-CHANGED: Interface Dot11Radio0/0/0, changed state to up
%LINEPROTO-5-UPDOWN: Line protocol on Interface Dot11Radio0/0/0, changed state to up
the router resets the interface.. -----------------------------------------------------------------------------------------------
R3(config-if) do show run
[cut]
!
!
dot11 ssid ADMIN2
authentication open
guest-mode
!
!
[cut]
!
interface Dot11Radio0/0/0
description test router 2
ip address 172.16.10.1 255.255.255.0
speed 12.0 18.0 24.0 36.0 48.0 54.0 6.0 9.0 basic-1.0 basic-11.0 basic-2.0 basic-5.5
ssid ADMIN2
!
[cut]
the SSID is created and assigned to the interface
To summarize.
Wrong: create the dot11 interface, then create the SSID from CONFIG-IF mode, which puts you into CONFIG-IF-SSID (there is no such mode on this router) mode, then modify the ssid from there...
Correct: create the dot11 interface. Exit CONFIG-IF and go back to GLOBAL CONFIG. Create the SSID which puts you in CONFIG-SSID mode. Configure the ssid. Then exit CONFIG-SSID. Back into CONFIG-IF, assign the SSID
We have one more task for R3- Configuring the DHCP pool for wireless clients.
R3(config)# ip dhcp pool Admin creating the pool name as "Admin"
R3(dhcp-config)# network 172.16.10.0 255.255.255.0
R3(dhcp-config)# default-router 172.16.10.1 aka default-gateway for clients in the pool
R3(dhcp-config)# ip name-server 172.16.10.4 dns server
*automatically exits dhcp-config prompt*
R3(config)# ip dhcp excluded-address 172.16.10.1 172.16.10.10 excludes the range given
172.16.10.1 is the router interface- we need to specifically exclude it from the pool
this setup should allow the wireless client to pick up an IP after connecting to the open SSID. However, I was having trouble at first-
even though I seemed to have the SSID set correctly, i was hitting a WEP password prompt
i didnt see any obvious issues with the wifi module im using on the laptop:
The Linksys-WPC300N module provides one 2.4GHz wireless interface suitable for connection to wireless networks. The module supports protocols that use Ethernet for LAN access.
I ended up creating a new SSID, with the same settings as the original:
R3(config)# dot11 ssid ADMIN2
R3(config-ssid)# guest-mode
R3(config-ssid)# authentication open
and then I assigned the ip address to ssid ADMIN2 instead of the orginal ADMIN ssid
R3(config)# int dot110/0/0
R3(config-if)# ip address 172.16.10.1 255.255.255.0
R3(config-if)# description WLAN for mobile user
R3(config-if)# no shut
R3(config-if)# ssid ADMIN2
R3# show run
Building configuration...
Current configuration : 1467 bytes
!
version 15.1
no service timestamps log datetime msec
no service timestamps debug datetime msec
no service password-encryption
!
hostname R3
!
!
!
enable secret 5 $1$mERr$V5ujdIM9bTB/I.ipB0gkJ0
!
!
ip dhcp excluded-address 172.16.10.1 172.16.10.10
!
ip dhcp pool Admin
network 172.16.10.0 255.255.255.0
default-router 172.16.10.1
!
dot11 ssid ADMIN
authentication open
guest-mode
!
dot11 ssid ADMIN2
authentication open
guest-mode
!
!
!
ip cef
no ipv6 cef
!
!
!
!
license udi pid CISCO2811/K9 sn FTX1017RE40-
!
!
!
!
!
!
!
!
!
no ip domain-lookup
ip name-server 172.16.10.4
!
!
spanning-tree mode pvst
!
!
!
!
!
!
interface FastEthernet0/0
description connection to corp router
ip address 10.1.5.2 255.255.255.0
duplex auto
speed auto
!
interface FastEthernet0/1
no ip address
duplex auto
speed auto
shutdown
!
interface Dot11Radio0/0/0
description WAN for mobile
ip address 172.16.10.1 255.255.255.0
speed 12.0 18.0 24.0 36.0 48.0 54.0 6.0 9.0 basic-1.0 basic-11.0 basic-2.0 basic-5.5
ssid ADMIN2
!
interface Dot11Radio0/0/1
no ip address
speed 18.0 36.0 48.0 54.0 9.0 basic-12.0 basic-24.0 basic-6.0
!
interface Vlan1
no ip address
shutdown
!
ip classless
!
ip flow-export version 9
!
!
!
banner motd ^C this is R3 $
this is R3 ^C
!
!
!
!
!
line con 0
exec-timeout 0 0
password console
logging synchronous
login
!
line aux 0
password aux
login
!
line vty 0 4
password telnet
login
line vty 5 15
password telnet
login
!
!
!
end
Recall the DHCP configuration on R3:
R3(config)# ip dhcp pool Admin creating the pool name as "Admin"
R3(dhcp-config)# network 172.16.10.0 255.255.255.0
R3(dhcp-config)# default-router 172.16.10.1 aka default-gateway for clients in the pool
R3(dhcp-config)# ip name-server 172.16.10.4 dns server
*automatically exits dhcp-config prompt*
R3(config)# ip dhcp excluded-address 172.16.10.1 172.16.10.10 excludes the range given
172.16.10.1 is the router interface- we need to specifically exclude it from the pool
we can check the configuration:
R3# show ip dhcp pool
Pool Admin :
Utilization mark (high/low) : 100 / 0
Subnet size (first/next) : 0 / 0
Total addresses : 254
Leased addresses : 1
Excluded addresses : 1
Pending event : none
1 subnet is currently in the pool
Current index IP address range Leased/Excluded/Total
172.16.10.1 172.16.10.1 - 172.16.10.254 1 / 1 / 254
R3# show ip dhcp binding
IP address Client-ID/ Lease expiration Type
Hardware address
172.16.10.11 00D0.979A.733B -- Automatic
the show command is becoming more familiar
R3# show ip?
access-lists List access lists
arp IP ARP table
bgp BGP information
cache IP fast-switching route cache
cef Cisco Express Forwarding
dhcp Show items in the DHCP database
eigrp IP-EIGRP show commands
inspect CBAC (Context Based Access Control) information
interface IP interface status and configuration
ips IPS (Intrusion Prevention System) information
nat IP NAT information
nbar Network-Based Application Recognition
ospf OSPF information
protocols IP routing protocol process parameters and statistics
rip IP RIP show commands
route IP routing table
ssh Information on SSH
we'll use show ip route soon on all the routers. For now, here is the output for R3:
R3# show ip route
Codes: L - local, C - connected, S - static, R - RIP, M - mobile, B - BGP
D - EIGRP, EX - EIGRP external, O - OSPF, IA - OSPF inter area
N1 - OSPF NSSA external type 1, N2 - OSPF NSSA external type 2
E1 - OSPF external type 1, E2 - OSPF external type 2, E - EGP
i - IS-IS, L1 - IS-IS level-1, L2 - IS-IS level-2, ia - IS-IS inter area
* - candidate default, U - per-user static route, o - ODR
P - periodic downloaded static route
Gateway of last resort is not set
10.0.0.0/8 is variably subnetted, 2 subnets, 2 masks
C 10.1.5.0/24 is directly connected, FastEthernet0/0
L 10.1.5.2/32 is directly connected, FastEthernet0/0
172.16.0.0/16 is variably subnetted, 2 subnets, 2 masks
C 172.16.10.0/24 is directly connected, Dot11Radio0/0/0
L 172.16.10.1/32 is directly connected, Dot11Radio0/0/0
Before moving on to the routing configurations, here is a review of the topology
I have switched over to the DrawIO diagram app to lay out the topology.
The Packet Tracer diagram becomes too crowded to see the labels; it's labeling system forces awkward positioning of the objects; the interface label's cant be moved, so if objects are too close together their labels cover eachother.. not good.
DrawIO allows a cleaner layout with plenty of room to label interfaces and ip addresses.
As a compromise, I'll use both.
I have the packet tracer objects spread out just enough to see the interfaces and the label for each router. From here I can jump into the CLI for each device.
The DrawIO diagram allows me to cleary see IP addresses
I want to also review all of the configurations we just performed:
PROBLEM
The book specifies that of the two serial conections between R1 and Corp, there should be a DCE on each end..
Both of my DCE's are on the same end.
First lets be sure we understand what DCE means:
networkengineering.stackexchange.com/
One side of the link (DCE), has to transmit the clock signal, which controls the data rate, and the other side (DTE) receives the clock signal.
That is good enough for now. Note that while the book does specify in the diagram that each side should have a DCE, it was not actually mentioned in the configs. We did not set a DCE or clock rate when conifguring those interfaces.
To fix this in my Packet Tracer topology, I did some quick research:
The book specifies that of the two serial conections between R1 and Corp, there should be a DCE on each end..
Both of my DCE's are on the same end.
First lets be sure we understand what DCE means:
networkengineering.stackexchange.com/
One side of the link (DCE), has to transmit the clock signal, which controls the data rate, and the other side (DTE) receives the clock signal.
That is good enough for now. Note that while the book does specify in the diagram that each side should have a DCE, it was not actually mentioned in the configs. We did not set a DCE or clock rate when conifguring those interfaces.
To fix this in my Packet Tracer topology, I did some quick research:
While this post wasnt pertaining to Packet Tracer, it got me thinking about the cable itself.
I deleted both of my existing serial connections and looked at the options for creating a new cable.
I noticed one is a DCE and one is a DTE:
Fixed the issue
back to the configuration overview: 4 routers, abbreviated show run output
Corp
interface FastEthernet0/0
description connection to R3
ip address 10.1.5.1 255.255.255.0
duplex auto
speed auto
!
interface FastEthernet0/1
no ip address
duplex auto
speed auto
shutdown
!
interface Serial0/0/0
description 1st connection to R1
ip address 10.1.2.1 255.255.255.0
!
interface Serial0/0/1
description 2nd connection to R1
ip address 10.1.3.1 255.255.255.0
clock rate 2000000
!
interface Serial0/1/0
description connection to R2
ip address 10.1.4.1 255.255.255.0
!
interface Vlan1
description Switch Card to Core Network
ip address 10.1.1.1 255.255.255.0
!
interface FastEthernet1/0
description switch port connection to WWW Server
switchport mode access
switchport nonegotiate
!
interface FastEthernet1/1
description switch port connection to Email Server
switchport mode access
switchport nonegotiate
!
interface FastEthernet1/2
description switch port connection to DNS Server
switchport mode access
switchport nonegotiate
!
R1
interface FastEthernet0/0
description connection to Finance
ip address 192.168.10.1 255.255.255.0
duplex auto
speed auto
!
interface FastEthernet0/1
description connection to Marketing
ip address 192.168.20.1 255.255.255.0
duplex auto
speed auto
!
interface Serial0/0/0
description 1st connection to Corp router
ip address 10.1.2.2 255.255.255.0
clock rate 2000000
!
interface Serial0/0/1
description 2nd connecction to Corp router
ip address 10.1.3.2 255.255.255.0
!
R2
interface FastEthernet0/0
description Connection to Sales PC
ip address 192.168.30.1 255.255.255.0
duplex auto
speed auto
!
interface FastEthernet0/1
description Connection to HR PC
ip address 192.168.40.1 255.255.255.0
duplex auto
speed auto
!
interface Serial0/0/0
description Connection to Corp Router
ip address 10.1.4.2 255.255.255.0
clock rate 2000000
!
interface Serial0/0/1
no ip address
clock rate 2000000
shutdown
!
R3
interface FastEthernet0/0
description connection to corp router
ip address 10.1.5.2 255.255.255.0
duplex auto
speed auto
!
interface FastEthernet0/1
no ip address
duplex auto
speed auto
shutdown
!
interface Dot11Radio0/0/0
description WAN for mobile
ip address 172.16.10.1 255.255.255.0
speed 12.0 18.0 24.0 36.0 48.0 54.0 6.0 9.0 basic-1.0 basic-11.0 basic-2.0 basic-5.5
ssid ADMIN2
and here is the output of show ip route for each router
Codes: C - connected, S - static, I - IGRP, R - RIP, M - mobile, B - BGP
D - EIGRP, EX - EIGRP external, O - OSPF, IA - OSPF inter area
N1 - OSPF NSSA external type 1, N2 - OSPF NSSA external type 2
E1 - OSPF external type 1, E2 - OSPF external type 2, E - EGP
i - IS-IS, L1 - IS-IS level-1, L2 - IS-IS level-2, ia - IS-IS inter area
* - candidate default, U - per-user static route, o - ODR
P - periodic downloaded static route
Gateway of last resort is not set
Corp
10.0.0.0/24 is subnetted, 2 subnets
C 10.1.2.0 is directly connected, Serial0/0/0
C 10.1.3.0 is directly connected, Serial0/0/1
C 192.168.10.0/24 is directly connected, FastEthernet0/0
C 192.168.20.0/24 is directly connected, FastEthernet0/1
R1
10.0.0.0/24 is subnetted, 2 subnets
C 10.1.2.0 is directly connected, Serial0/0/0
C 10.1.3.0 is directly connected, Serial0/0/1
C 192.168.10.0/24 is directly connected, FastEthernet0/0
C 192.168.20.0/24 is directly connected, FastEthernet0/1
R2
10.0.0.0/24 is subnetted, 1 subnets
C 10.1.4.0 is directly connected, Serial0/0/0
C 192.168.30.0/24 is directly connected, FastEthernet0/0
C 192.168.40.0/24 is directly connected, FastEthernet0/1
R3
10.0.0.0/8 is variably subnetted, 2 subnets, 2 masks
C 10.1.5.0/24 is directly connected, FastEthernet0/0
L 10.1.5.2/32 is directly connected, FastEthernet0/0
172.16.0.0/16 is variably subnetted, 2 subnets, 2 masks
C 172.16.10.0/24 is directly connected, Dot11Radio0/0/0
L 172.16.10.1/32 is directly connected, Dot11Radio0/0/0
Note that this is before we have configured any 'routing'. We are seeing configured, directly connected networks.
The output for R3 is particularly interesting
What does 'variably' subnetted mean, and what is the "L" next to these routes. And why do they have a mask of 32?
R3
10.0.0.0/8 is variably subnetted, 2 subnets, 2 masks
C 10.1.5.0/24 is directly connected, FastEthernet0/0
L 10.1.5.2/32 is directly connected, FastEthernet0/0
172.16.0.0/16 is variably subnetted, 2 subnets, 2 masks
C 172.16.10.0/24 is directly connected, Dot11Radio0/0/0
L 172.16.10.1/32 is directly connected, Dot11Radio0/0/0
Cisco forums
That makes sense, but my question is why did the other routing tables not behave the same way? R3 is the only one that shows "L" routes.
The book tells us we're using two different model routers, and indeed they are running different IOS versions:
NOTE that at the time the book was published IOS 15 was not released yet, so the book assumes all routers are running 12.4
But that still doesnt explain why Corp and R3 are behaving differently..
Corp
10.0.0.0/24 is subnetted, 2 subnets
C 10.1.2.0 is directly connected, Serial0/0/0
C 10.1.3.0 is directly connected, Serial0/0/1
C 192.168.10.0/24 is directly connected, FastEthernet0/0
C 192.168.20.0/24 is directly connected, FastEthernet0/1
R1
10.0.0.0/24 is subnetted, 2 subnets
C 10.1.2.0 is directly connected, Serial0/0/0
C 10.1.3.0 is directly connected, Serial0/0/1
C 192.168.10.0/24 is directly connected, FastEthernet0/0
C 192.168.20.0/24 is directly connected, FastEthernet0/1
R2
10.0.0.0/24 is subnetted, 1 subnets
C 10.1.4.0 is directly connected, Serial0/0/0
C 192.168.30.0/24 is directly connected, FastEthernet0/0
C 192.168.40.0/24 is directly connected, FastEthernet0/1
R3
10.0.0.0/8 is variably subnetted, 2 subnets, 2 masks
C 10.1.5.0/24 is directly connected, FastEthernet0/0
L 10.1.5.2/32 is directly connected, FastEthernet0/0
172.16.0.0/16 is variably subnetted, 2 subnets, 2 masks
C 172.16.10.0/24 is directly connected, Dot11Radio0/0/0
L 172.16.10.1/32 is directly connected, Dot11Radio0/0/0
how are Corp and R3 different? The answer is, they are not...
I have accidentally displayed the R1 output to the Corp windows. Error in translating data from the IOS to this webpage..
here's the corrected output.
Corp
10.0.0.0/8 is variably subnetted, 10 subnets, 2 masks
C 10.1.1.0/24 is directly connected, Vlan1
L 10.1.1.1/32 is directly connected, Vlan1
C 10.1.2.0/24 is directly connected, Serial0/0/0
L 10.1.2.1/32 is directly connected, Serial0/0/0
C 10.1.3.0/24 is directly connected, Serial0/0/1
L 10.1.3.1/32 is directly connected, Serial0/0/1
C 10.1.4.0/24 is directly connected, Serial0/1/0
L 10.1.4.1/32 is directly connected, Serial0/1/0
C 10.1.5.0/24 is directly connected, FastEthernet0/0
L 10.1.5.1/32 is directly connected, FastEthernet0/0
R1
10.0.0.0/24 is subnetted, 2 subnets
C 10.1.2.0 is directly connected, Serial0/0/0
C 10.1.3.0 is directly connected, Serial0/0/1
C 192.168.10.0/24 is directly connected, FastEthernet0/0
C 192.168.20.0/24 is directly connected, FastEthernet0/1
R2
10.0.0.0/24 is subnetted, 1 subnets
C 10.1.4.0 is directly connected, Serial0/0/0
C 192.168.30.0/24 is directly connected, FastEthernet0/0
C 192.168.40.0/24 is directly connected, FastEthernet0/1
R3
10.0.0.0/8 is variably subnetted, 2 subnets, 2 masks
C 10.1.5.0/24 is directly connected, FastEthernet0/0
L 10.1.5.2/32 is directly connected, FastEthernet0/0
172.16.0.0/16 is variably subnetted, 2 subnets, 2 masks
C 172.16.10.0/24 is directly connected, Dot11Radio0/0/0
L 172.16.10.1/32 is directly connected, Dot11Radio0/0/0
We do indeed see consistent behavior differences between IOS versions 12.4 and 15.1
recap Corp and R3 outputs:
update topology with Router versions
That covers the first half of Chapter 8. Now we are ready to configure IP routing on our network.
There are three ways: Static, Default, Dynamic
To set up static routes, we simply need to program the routes using the ip route command
Syntax
ip route [ destination network ] [ mask ] [ next hop ] [ exitinterface ] [ administrative distance ] [ permanent ]
destination network and mask the network data we're adding to the routing table
next-hop address the address of the next-hop router that will receive the packet and forward to the remote network.
This is the IP address of a router interface that is directly connected. It must be pingable.
exit interface can be used instead of next hop address
administrative distance by default, static routes have an admin distance of 1 if you use a next hop, or 0 if you use exit interface.
You can change the value by adding an administrative weight at the end of the command. More on this later with dynamic routing.
permanent if the interface is shut down or the router cant communicate to the next hp router, the route will automatically be discarded from the table by default.
The 'permanent' option keeps the entry in the routing table indefenitely.
-----------------------------------------------------------------------------------------------------
Corp has automatically picked up 5 routes that are directly connected:
10.1.1.0 to corp switch card
10.1.2.0 to R1
10.1.3.0 to R1
10.1.4.0 to R2
10.1.5.0 to R3
We need to program 5 more routes:
192.168.10.0 traverse R1
192.168.20.0 traverse R1
192.168.30.0 traverse R1
192.168.40.0 traverse R2
172.16.10.0 traverse R3
-----------------------------------------------------------------------------------------------------
R1 has automatically picked up 4 routes that are directly connected:
10.1.2.0
10.1.3.0
192.168.10.0
192.168.20.0
We need to program 6 more routes:
10.1.1.0
10.1.4.0
10.1.5.0
192.168.30.0
192.168.40.0
172.16.10.0
-----------------------------------------------------------------------------------------------------
R2 has automatically picked up 3 routes that are directly connected:
10.1.4.0
192.168.30.0
192.168.40.0
We need to program 7 more routes:
10.1.1.0
10.1.2.0
10.1.3.0
10.1.5.0
192.168.10.0
192.168.20.0
172.16.10.0
-----------------------------------------------------------------------------------------------------
R3 has automatically picked up 2 routes that are directly connected:
10.1.5.0
172.16.10.0
We need to program 8 more routes:
10.1.1.0
10.1.2.0
10.1.3.0
10.1.4.0
192.168.10.0
192.168.20.0
192.168.30.0
192.168.40.0
Notice the pattern- each router ends up with 10 routes
There are 10 routes total in this topology. AKA ten broadcast domains
Programming the routes
Corp
Corp(config)# ip route 192.168.10.0 255.255.255.0 10.1.2.2 150
Corp(config)# ip route 192.168.20.0 255.255.255.0 10.1.3.2 150
Corp(config)# ip route 192.168.30.0 255.255.255.0 10.1.4.2 150
Corp(config)# ip route 192.168.40.0 255.255.255.0 10.1.4.2 150
Corp(config)# ip route 172.16.10.0 255.255.255.0 10.1.5.2 150
Corp(config)# do show ip route
Corp(config)# ip route 192.168.10.0 255.255.255.0 10.1.2.2 150
Corp(config)# ip route 192.168.20.0 255.255.255.0 10.1.3.2 150
Corp(config)# ip route 192.168.30.0 255.255.255.0 10.1.4.2 150
Corp(config)# ip route 192.168.40.0 255.255.255.0 10.1.4.2 150
Corp(config)# ip route 172.16.10.0 255.255.255.0 10.1.5.2 150
Corp(config)# do show ip route
In the first line, the router is saying that a
classful A network is being subnetted
There are 5 routes directly connected
We see two lines per route (one for the network and one
for the interface(/32)-
10.0.0.0/8 is variably subnetted, 10 subnets, 2 masks
C 10.1.1.0/24 is directly connected, Vlan1
L 10.1.1.1/32 is directly connected, Vlan1
C 10.1.2.0/24 is directly connected, Serial0/0/0
L 10.1.2.1/32 is directly connected, Serial0/0/0
C 10.1.3.0/24 is directly connected, Serial0/0/1
L 10.1.3.1/32 is directly connected, Serial0/0/1
C 10.1.4.0/24 is directly connected, Serial0/1/0
L 10.1.4.1/32 is directly connected, Serial0/1/0
C 10.1.5.0/24 is directly connected, FastEthernet0/0
L 10.1.5.1/32 is directly connected, FastEthernet0/0
and 5 routes that require traversal of a router to reach
172.16.0.0/24 is subnetted, 1 subnets
S 172.16.10.0/24 [150/0] via 10.1.5.2
S 192.168.10.0/24 [150/0] via 10.1.2.2
S 192.168.20.0/24 [150/0] via 10.1.3.2
S 192.168.30.0/24 [150/0] via 10.1.4.2
S 192.168.40.0/24 [150/0] via 10.1.4.2
R1
R1(config)# ip route 10.1.1.0 255.255.255.0 10.1.2.1 150
R1(config)# ip route 10.1.4.0 255.255.255.0 10.1.3.1 150
R1(config)# ip route 10.1.5.0 255.255.255.0 10.1.2.1 150
R1(config)# ip route 192.168.30.0 255.255.255.0 10.1.3.1 150
R1(config)# ip route 192.168.40.0 255.255.255.0 10.1.2.1 150
R1(config)# ip route 172.16.10.0 255.255.255.0 10.1.3.1 150
the only way to get across the corp router is to go into it via 10.1.2.1 or 10.1.3.1
R1(config)# do show ip route
R1(config)# ip route 10.1.1.0 255.255.255.0 10.1.2.1 150
R1(config)# ip route 10.1.4.0 255.255.255.0 10.1.3.1 150
R1(config)# ip route 10.1.5.0 255.255.255.0 10.1.2.1 150
R1(config)# ip route 192.168.30.0 255.255.255.0 10.1.3.1 150
R1(config)# ip route 192.168.40.0 255.255.255.0 10.1.2.1 150
R1(config)# ip route 172.16.10.0 255.255.255.0 10.1.3.1 150
the only way to get across the corp router is to go into it via 10.1.2.1 or 10.1.3.1
R1(config)# do show ip route
10.0.0.0/24 is subnetted, 5 subnets
S 10.1.1.0 [150/0] via 10.1.2.1
C 10.1.2.0 is directly connected, Serial0/0/0
C 10.1.3.0 is directly connected, Serial0/0/1
S 10.1.4.0 [150/0] via 10.1.3.1
S 10.1.5.0 [150/0] via 10.1.2.1
172.16.0.0/24 is subnetted, 1 subnets
S 172.16.10.0 [150/0] via 10.1.3.1
C 192.168.10.0/24 is directly connected, FastEthernet0/0
C 192.168.20.0/24 is directly connected, FastEthernet0/1
S 192.168.30.0/24 [150/0] via 10.1.3.1
S 192.168.40.0/24 [150/0] via 10.1.2.1
R2
R2(config)# iproute 10.1.1.0 255.255.255.0 10.1.4.1 150
R2(config)# iproute 10.1.2.0 255.255.255.0 10.1.4.1 150
R2(config)# iproute 10.1.3.0 255.255.255.0 10.1.4.1 150
R2(config)# iproute 10.1.5.0 255.255.255.0 10.1.4.1 150
R2(config)# iproute 192.168.10.0 255.255.255.0 10.1.4.1 150
R2(config)# iproute 192.168.20.0 255.255.255.0 10.1.4.1 150
the only way to get across Corp is to go into it via 10.1.4.1
R2(config)# do show ip route
10.0.0.0/24 is subnetted, 5 subnets
S 10.1.1.0 [150/0] via 10.1.4.1
S 10.1.2.0 [150/0] via 10.1.4.1
S 10.1.3.0 [150/0] via 10.1.4.1
C 10.1.4.0 is directly connected, Serial0/0/0
S 10.1.5.0 [150/0] via 10.1.4.1
172.16.0.0/24 is subnetted, 1 subnets
S 172.16.10.0 [150/0] via 10.1.4.1
S 192.168.10.0/24 [150/0] via 10.1.4.1
S 192.168.20.0/24 [150/0] via 10.1.4.1
C 192.168.30.0/24 is directly connected, FastEthernet0/0
C 192.168.40.0/24 is directly connected, FastEthernet0/1
R3
R3(config)# ip route 10.1.1.0 255.255.255.0 fastethernet 0/0 150
R3(config)# ip route 10.1.2.0 255.255.255.0 fastethernet 0/0 150
R3(config)# ip route 10.1.3.0 255.255.255.0 fastethernet 0/0 150
R3(config)# ip route 10.1.4.0 255.255.255.0 fastethernet 0/0 150
R3(config)# ip route 192.168.10.0 255.255.255.0 fastethernet 0/0 150
R3(config)# ip route 192.168.20.0 255.255.255.0 fastethernet 0/0 150
R3(config)# ip route 192.168.30.0 255.255.255.0 fastethernet 0/0 150
R3(config)# ip route 192.168.40.0 255.255.255.0 fastethernet 0/0 150
the only way to get across Corp is to EXIT R3 via F0/0
R3(config)# do show ip route
10.0.0.0/8 is variably subnetted, 6 subnets, 2 masks
S 10.1.1.0/24 is directly connected, FastEthernet0/0
S 10.1.2.0/24 is directly connected, FastEthernet0/0
S 10.1.3.0/24 is directly connected, FastEthernet0/0
S 10.1.4.0/24 is directly connected, FastEthernet0/0
C 10.1.5.0/24 is directly connected, FastEthernet0/0
L 10.1.5.2/32 is directly connected, FastEthernet0/0
172.16.0.0/16 is variably subnetted, 2 subnets, 2 masks
C 172.16.10.0/24 is directly connected, Dot11Radio0/0/0
L 172.16.10.1/32 is directly connected, Dot11Radio0/0/0
S 192.168.10.0/24 is directly connected, FastEthernet0/0
S 192.168.20.0/24 is directly connected, FastEthernet0/0
S 192.168.30.0/24 is directly connected, FastEthernet0/0
S 192.168.40.0/24 is directly connected, FastEthernet0/0
before verifying connectivity across the network, we need to make sure all of our hosts are set. The book is giving us the IP addresses for the servers:
Server Gateway 10.1.1.1
ServerWeb 10.1.1.2
ServerEmail 10.1.1.3
ServerDNS 10.1.1.4
Now we can do some testing across the network:
R3# ping 10.1.2.2 traverse Corp to R1
R3# ping 10.1.1.1 traverse Corp to a Corp interface we arent directly connected to
R3# ping 10.1.1.2 traverse Corp to Web server
R3# ping 10.1.1.3 traverse Corp to Email server
R3# ping 10.1.1.4 traverse Corp to DNS server
MobileUser ping 192.168.10.2 traverse R3, Corp, R1 to Finance client
MobileUser tracert 192.168.10.2 traverse R3, Corp, R1 to Finance client
ALSO NOTE that tracert is a Windows command.
the IOS equivalent is traceroute
notice how the output differs from the Windows command
R3 traceroute 192.168.10.2
R3# ping 10.1.2.2 traverse Corp to R1
R3# ping 10.1.1.1 traverse Corp to a Corp interface we arent directly connected to
R3# ping 10.1.1.2 traverse Corp to Web server
R3# ping 10.1.1.3 traverse Corp to Email server
R3# ping 10.1.1.4 traverse Corp to DNS server
MobileUser ping 192.168.10.2 traverse R3, Corp, R1 to Finance client
MobileUser tracert 192.168.10.2 traverse R3, Corp, R1 to Finance client
Tracing route to 192.168.10.2 over a maximum of 30 hops:
1 19 ms 5 ms 20 ms 172.16.10.1
2 20 ms 6 ms 11 ms 10.1.5.1
3 11 ms 15 ms 10 ms 10.1.3.2
4 9 ms 13 ms 22 ms 192.168.10.2
Trace complete.
notice how the trace doesnt count an egress as a hop, only an ingress
ALSO NOTE that tracert is a Windows command.
the IOS equivalent is traceroute
notice how the output differs from the Windows command
R3 traceroute 192.168.10.2
Type escape sequence to abort.
Tracing the route to 192.168.10.2
1 10.1.5.1 0 msec 0 msec 0 msec
2 10.1.2.2 6 msec 0 msec 5 msec
3 192.168.10.2 1 msec 4 msec 3 msec
Default Routing
we could have done this on R3
R3(config)# ip route 0.0.0.0 0.0.0.0 10.1.5.1
R3(config)# ip route 0.0.0.0 0.0.0.0 10.1.5.1
as an alternative to this configuration on R3
R3(config)# ip route 10.1.1.0 255.255.255.0 fastethernet 0/0 150
R3(config)# ip route 10.1.2.0 255.255.255.0 fastethernet 0/0 150
R3(config)# ip route 10.1.3.0 255.255.255.0 fastethernet 0/0 150
R3(config)# ip route 10.1.4.0 255.255.255.0 fastethernet 0/0 150
R3(config)# ip route 192.168.10.0 255.255.255.0 fastethernet 0/0 150
R3(config)# ip route 192.168.20.0 255.255.255.0 fastethernet 0/0 150
R3(config)# ip route 192.168.30.0 255.255.255.0 fastethernet 0/0 150
R3(config)# ip route 192.168.40.0 255.255.255.0 fastethernet 0/0 150
the only way to get across Corp is to EXIT R3 via F0/0
R3(config)# ip route 10.1.1.0 255.255.255.0 fastethernet 0/0 150
R3(config)# ip route 10.1.2.0 255.255.255.0 fastethernet 0/0 150
R3(config)# ip route 10.1.3.0 255.255.255.0 fastethernet 0/0 150
R3(config)# ip route 10.1.4.0 255.255.255.0 fastethernet 0/0 150
R3(config)# ip route 192.168.10.0 255.255.255.0 fastethernet 0/0 150
R3(config)# ip route 192.168.20.0 255.255.255.0 fastethernet 0/0 150
R3(config)# ip route 192.168.30.0 255.255.255.0 fastethernet 0/0 150
R3(config)# ip route 192.168.40.0 255.255.255.0 fastethernet 0/0 150
the only way to get across Corp is to EXIT R3 via F0/0
This is called default routing. It should only be used on 'stub routers'- those with only one exit path out of the network.
if you try to put a default route on a non-stub router, you could create loops, since there will be more than one path to other routers...
Think of a default route as a static route that uses a wildcard address and mask. The wildcard is 0.0.0.0
to further analyze this comparison, I'm going to remove the routes from R3...
R3(config)# no ip route 10.1.1.0 255.255.255.0 fastethernet0/0 150
R3(config)# no ip route 10.1.2.0 255.255.255.0 fastethernet0/0 150
R3(config)# no ip route 10.1.3.0 255.255.255.0 fastethernet0/0 150
R3(config)# no ip route 10.1.4.0 255.255.255.0 fastethernet0/0 150
R3(config)# no ip route 192.168.10.0 255.255.255.0 fastethernet0/0 150
R3(config)# no ip route 192.168.20.0 255.255.255.0 fastethernet0/0 150
R3(config)# no ip route 192.168.30.0 255.255.255.0 fastethernet0/0 150
R3(config)# no ip route 192.168.40.0 255.255.255.0 fastethernet0/0 150
and then set the default route instead.
R3# ip route 0.0.0.0 0.0.0.0 10.1.5.1 --- ingress at next hop
OR
R3# ip route 0.0.0.0 0.0.0.0 Fa0/0 --- egress interface
Then compare the output of show ip route
static routes set
R3# show ip route
R3# show ip route
Gateway of last resort is not set
10.0.0.0/8 is variably subnetted, 6 subnets, 2 masks
S 10.1.1.0/24 is directly connected, FastEthernet0/0
S 10.1.2.0/24 is directly connected, FastEthernet0/0
S 10.1.3.0/24 is directly connected, FastEthernet0/0
S 10.1.4.0/24 is directly connected, FastEthernet0/0
C 10.1.5.0/24 is directly connected, FastEthernet0/0
L 10.1.5.2/32 is directly connected, FastEthernet0/0
172.16.0.0/16 is variably subnetted, 2 subnets, 2 masks
C 172.16.10.0/24 is directly connected, Dot11Radio0/0/0
L 172.16.10.1/32 is directly connected, Dot11Radio0/0/0
S 192.168.10.0/24 is directly connected, FastEthernet0/0
S 192.168.20.0/24 is directly connected, FastEthernet0/0
S 192.168.30.0/24 is directly connected, FastEthernet0/0
S 192.168.40.0/24 is directly connected, FastEthernet0/0
default route set
R3# show ip route
anything not included in those networks goes to ingress of attached neighbor Corp 10.1.5.1 in this toplogy, that includes:
192.168.10.0
192.168.20.0
192.168.30.0
192.168.40.0
and
10.1.1.0
10.1.2.0
10.1.3.0
10.1.4.0
R3# show ip route
Gateway of last resort is 10.1.5.1 to network 0.0.0.0
10.0.0.0/8 is variably subnetted, 2 subnets, 2 masks
C 10.1.5.0/24 is directly connected, FastEthernet0/0
L 10.1.5.2/32 is directly connected, FastEthernet0/0
172.16.0.0/16 is variably subnetted, 2 subnets, 2 masks
C 172.16.10.0/24 is directly connected, Dot11Radio0/0/0
L 172.16.10.1/32 is directly connected, Dot11Radio0/0/0
S* 0.0.0.0/0 [1/0] via 10.1.5.1
two directly connected networks- 10.1.5.0 and 172.16.10.0
anything not included in those networks goes to ingress of attached neighbor Corp 10.1.5.1 in this toplogy, that includes:
192.168.10.0
192.168.20.0
192.168.30.0
192.168.40.0
and
10.1.1.0
10.1.2.0
10.1.3.0
10.1.4.0
RIP Routing Information Protocol
R1(config)# router ?
bgp Border Gateway Protocol (BGP)
eigrp Enhanced Interior Gateway Routing Protocol (EIGRP)
ospf Open Shortest Path First (OSPF)
rip Routing Information Protocol (RIP)
set RIP on Corp
Corp(config)# router rip
Corp(config-router)# network 10.0.0.0
Corp(config)# router rip
Corp(config-router)# network 10.0.0.0
set RIP on R1
R1(config)# router rip
R1(config-router)# network 10.0.0.0
R1(config)# router rip
R1(config-router)# network 10.0.0.0
R1 routing table
R1(config)# do show ip route
10.0.0.0/24 is subnetted, 5 subnets
R 10.1.1.0 [120/1] via 10.1.2.1, 00:00:21, Serial0/0/0
[120/1] via 10.1.3.1, 00:00:21, Serial0/0/1
C 10.1.2.0 is directly connected, Serial0/0/0
C 10.1.3.0 is directly connected, Serial0/0/1
R 10.1.4.0 [120/1] via 10.1.2.1, 00:00:21, Serial0/0/0
[120/1] via 10.1.3.1, 00:00:21, Serial0/0/1
R 10.1.5.0 [120/1] via 10.1.2.1, 00:00:21, Serial0/0/0
[120/1] via 10.1.3.1, 00:00:21, Serial0/0/1
172.16.0.0/24 is subnetted, 1 subnets
S 172.16.10.0 [150/0] via 10.1.3.1
C 192.168.10.0/24 is directly connected, FastEthernet0/0
C 192.168.20.0/24 is directly connected, FastEthernet0/1
S 192.168.30.0/24 [150/0] via 10.1.3.1
S 192.168.40.0/24 [150/0] via 10.1.2.1
here's R1 before RIP, with only static routes set:
R1(config)# do show ip route
10.0.0.0/24 is subnetted, 5 subnets
S 10.1.1.0 [150/0] via 10.1.2.1
C 10.1.2.0 is directly connected, Serial0/0/0
C 10.1.3.0 is directly connected, Serial0/0/1
S 10.1.4.0 [150/0] via 10.1.3.1
S 10.1.5.0 [150/0] via 10.1.2.1
172.16.0.0/24 is subnetted, 1 subnets
S 172.16.10.0 [150/0] via 10.1.3.1
C 192.168.10.0/24 is directly connected, FastEthernet0/0
C 192.168.20.0/24 is directly connected, FastEthernet0/1
S 192.168.30.0/24 [150/0] via 10.1.3.1
S 192.168.40.0/24 [150/0] via 10.1.2.1
These RIP routes are being advertised as available *to other RIP routers*.
CORP is advertisting THREE routes via RIP to R1 right now
10.1.1.0
10.1.4.0
10.1.5.0
access to those networks can be achieved by R1 by going THROUGH CORP via ingress .2.1 or .3.1
The advantage..... is that we didnt statically program these routes
we engaged RIP, on BOTH routers- R1 and Corp, and handed them BOTH the network "10.0.0.0" So, why did RIP choose to display these particular routes Keep in mind that the output above is from R1 only... In the context of the R1 ROUTER ONLY, there are three relevant routes within the "10.0.0.0" parameter we specified. The three routes involve Corp.
Corp is sending RIP data about these routes to Corp.
Lets look closer at how this is happening:
here's our starting point before any RIP is set
here's our routing tables after i set RIP with 10.0.0.0 on both..
FIRST i set it on Corp, then R1.(per the book's instructions) As a result we are seeing RIP routes in R1 only....
then I went back to a fresh packet tracer file with no RIP set. And I set RIP in the opposite order;
FIRST i set it on R1, then Corp. And again, we are seeing RIP routes in R1 only....
I wanted to prove that it didnt matter which order we enabled RIP on the two routers. What matters here is that we enable RIP on both of them with the criteria of 10.0.0.0
Recall the topology:
if Corp and R1 are set for RIP and given the criteria 10.0.0.0, meaning that we are trying to reach networks within that range, then it follows that Corp will advertise 1.1.0, 1.4.0, and 1.5.0 to R1, because Corp stands between those networks and R1
"Hi R1, I'm Corp I have three networks that fall inside 10.0.0.0, and you can reach them through me via .2.1 or .3.1"
It also follows that Corp's routing table shows no RIP routes- because R1 isnt advertising any. R1 doesnt have any networks in the 10.0.0.0 range that Corp could reach
To further clarify this, we'll proceed with the book's instructions. We'll now set more RIP routes on R1
R1(config)# router rip
R1(config-router)# network 192.168.10.0
R1(config-router)# network 192.168.20.0
Corp routing table before RIP set on R1:
Corp# show ip route
10.0.0.0/8 is variably subnetted, 10 subnets, 2 masks
C 10.1.1.0/24 is directly connected, Vlan1
L 10.1.1.1/32 is directly connected, Vlan1
C 10.1.2.0/24 is directly connected, Serial0/0/0
L 10.1.2.1/32 is directly connected, Serial0/0/0
C 10.1.3.0/24 is directly connected, Serial0/0/1
L 10.1.3.1/32 is directly connected, Serial0/0/1
C 10.1.4.0/24 is directly connected, Serial0/1/0
L 10.1.4.1/32 is directly connected, Serial0/1/0
C 10.1.5.0/24 is directly connected, FastEthernet0/0
L 10.1.5.1/32 is directly connected, FastEthernet0/0
172.16.0.0/24 is subnetted, 1 subnets
S 172.16.10.0/24 [150/0] via 10.1.5.2
S 192.168.10.0/24 [150/0] via 10.1.2.2
S 192.168.20.0/24 [150/0] via 10.1.3.2
S 192.168.30.0/24 [150/0] via 10.1.4.2
S 192.168.40.0/24 [150/0] via 10.1.4.2
Corp routing table after RIP set on R1:
Gateway of last resort is not set
10.0.0.0/8 is variably subnetted, 10 subnets, 2 masks
C 10.1.1.0/24 is directly connected, Vlan1
L 10.1.1.1/32 is directly connected, Vlan1
C 10.1.2.0/24 is directly connected, Serial0/0/0
L 10.1.2.1/32 is directly connected, Serial0/0/0
C 10.1.3.0/24 is directly connected, Serial0/0/1
L 10.1.3.1/32 is directly connected, Serial0/0/1
C 10.1.4.0/24 is directly connected, Serial0/1/0
L 10.1.4.1/32 is directly connected, Serial0/1/0
C 10.1.5.0/24 is directly connected, FastEthernet0/0
L 10.1.5.1/32 is directly connected, FastEthernet0/0
nothing changed so far
172.16.0.0/24 is subnetted, 1 subnets
S 172.16.10.0/24 [150/0] via 10.1.5.2
no change
R 192.168.10.0/24 [120/1] via 10.1.2.2, 00:00:08, Serial0/0/0
[120/1] via 10.1.3.2, 00:00:08, Serial0/0/1
RIP overrides static- 2 paths available now
R 192.168.20.0/24 [120/1] via 10.1.2.2, 00:00:08, Serial0/0/0
[120/1] via 10.1.3.2, 00:00:08, Serial0/0/1
RIP overrides static- 2 paths available now
S 192.168.30.0/24 [150/0] via 10.1.4.2
no change
S 192.168.40.0/24 [150/0] via 10.1.4.2
no change
"Hi Corp- I'm R1 and I have zero networks that fall inside 10.0.0.0, however I do have some networks that fall within 192.168.20.0 and 192.168.10.0
and you can reach them through me(R1) if you ingress at .1.2.2 or .1.3.2"
ok, we have the concept down. Time to proceed and set up RIP on R2............
R2(config)# router rip
R2(config-router)# network 10.0.0.0
R2(config-router)# network 192.168.30.0
R2(config-router)# network 192.168.40.0
R2 before RIP enabled
R2# show ip route
R2# show ip route
10.0.0.0/24 is subnetted, 5 subnets
S 10.1.1.0 [150/0] via 10.1.4.1
S 10.1.2.0 [150/0] via 10.1.4.1
S 10.1.3.0 [150/0] via 10.1.4.1
C 10.1.4.0 is directly connected, Serial0/0/0
S 10.1.5.0 [150/0] via 10.1.4.1
172.16.0.0/24 is subnetted, 1 subnets
S 172.16.10.0 [150/0] via 10.1.4.1
S 192.168.10.0/24 [150/0] via 10.1.4.1
S 192.168.20.0/24 [150/0] via 10.1.4.1
C 192.168.30.0/24 is directly connected, FastEthernet0/0
C 192.168.40.0/24 is directly connected, FastEthernet0/1
R2 after RIP added
R2# show ip route
R2# show ip route
10.0.0.0/24 is subnetted, 5 subnets
R 10.1.1.0 [120/1] via 10.1.4.1, 00:00:24, Serial0/0/0
from corp
R 10.1.2.0 [120/1] via 10.1.4.1, 00:00:24, Serial0/0/0
from corp
R 10.1.3.0 [120/1] via 10.1.4.1, 00:00:24, Serial0/0/0
from corp
C 10.1.4.0 is directly connected, Serial0/0/0
R 10.1.5.0 [120/1] via 10.1.4.1, 00:00:24, Serial0/0/0
from corp
172.16.0.0/24 is subnetted, 1 subnets
S 172.16.10.0 [150/0] via 10.1.4.1
R 192.168.10.0/24 [120/2] via 10.1.4.1, 00:00:24, Serial0/0/0
from R1 via corp
R 192.168.20.0/24 [120/2] via 10.1.4.1, 00:00:24, Serial0/0/0
from R1 via corp
C 192.168.30.0/24 is directly connected, FastEthernet0/0
C 192.168.40.0/24 is directly connected, FastEthernet0/1
now lets compare the Corp and R1 routing tables- before RIP was set on R2 and after
Corp before R2 RIP
Corp# show ip route
10.0.0.0/8 is variably subnetted, 10 subnets, 2 masks
C 10.1.1.0/24 is directly connected, Vlan1
L 10.1.1.1/32 is directly connected, Vlan1
C 10.1.2.0/24 is directly connected, Serial0/0/0
L 10.1.2.1/32 is directly connected, Serial0/0/0
C 10.1.3.0/24 is directly connected, Serial0/0/1
L 10.1.3.1/32 is directly connected, Serial0/0/1
C 10.1.4.0/24 is directly connected, Serial0/1/0
L 10.1.4.1/32 is directly connected, Serial0/1/0
C 10.1.5.0/24 is directly connected, FastEthernet0/0
L 10.1.5.1/32 is directly connected, FastEthernet0/0
172.16.0.0/24 is subnetted, 1 subnets
S 172.16.10.0/24 [150/0] via 10.1.5.2
R 192.168.10.0/24 [120/1] via 10.1.2.2, 00:00:02, Serial0/0/0
[120/1] via 10.1.3.2, 00:00:02, Serial0/0/1
R 192.168.20.0/24 [120/1] via 10.1.2.2, 00:00:02, Serial0/0/0
[120/1] via 10.1.3.2, 00:00:02, Serial0/0/1
from R1
S 192.168.30.0/24 [150/0] via 10.1.4.2
S 192.168.40.0/24 [150/0] via 10.1.4.2
Corp after R2 RIP
Corp# show ip route
10.0.0.0/8 is variably subnetted, 10 subnets, 2 masks
C 10.1.1.0/24 is directly connected, Vlan1
L 10.1.1.1/32 is directly connected, Vlan1
C 10.1.2.0/24 is directly connected, Serial0/0/0
L 10.1.2.1/32 is directly connected, Serial0/0/0
C 10.1.3.0/24 is directly connected, Serial0/0/1
L 10.1.3.1/32 is directly connected, Serial0/0/1
C 10.1.4.0/24 is directly connected, Serial0/1/0
L 10.1.4.1/32 is directly connected, Serial0/1/0
C 10.1.5.0/24 is directly connected, FastEthernet0/0
L 10.1.5.1/32 is directly connected, FastEthernet0/0
172.16.0.0/24 is subnetted, 1 subnets
S 172.16.10.0/24 [150/0] via 10.1.5.2
R 192.168.10.0/24 [120/1] via 10.1.2.2, 00:00:19, Serial0/0/0
[120/1] via 10.1.3.2, 00:00:19, Serial0/0/1
R 192.168.20.0/24 [120/1] via 10.1.2.2, 00:00:19, Serial0/0/0
[120/1] via 10.1.3.2, 00:00:19, Serial0/0/1
from R1
R 192.168.30.0/24 [120/1] via 10.1.4.2, 00:00:15, Serial0/1/0
R 192.168.40.0/24 [120/1] via 10.1.4.2, 00:00:15, Serial0/1/0
from R2
R1 before R2 RIP
R1# show ip route
10.0.0.0/24 is subnetted, 5 subnets
R 10.1.1.0 [120/1] via 10.1.2.1, 00:00:05, Serial0/0/0
[120/1] via 10.1.3.1, 00:00:05, Serial0/0/1
from Corp
C 10.1.2.0 is directly connected, Serial0/0/0
C 10.1.3.0 is directly connected, Serial0/0/1
R 10.1.4.0 [120/1] via 10.1.2.1, 00:00:05, Serial0/0/0
[120/1] via 10.1.3.1, 00:00:05, Serial0/0/1
R 10.1.5.0 [120/1] via 10.1.2.1, 00:00:05, Serial0/0/0
[120/1] via 10.1.3.1, 00:00:05, Serial0/0/1
from Corp
172.16.0.0/24 is subnetted, 1 subnets
S 172.16.10.0 [150/0] via 10.1.3.1
C 192.168.10.0/24 is directly connected, FastEthernet0/0
C 192.168.20.0/24 is directly connected, FastEthernet0/1
S 192.168.30.0/24 [150/0] via 10.1.3.1
S 192.168.40.0/24 [150/0] via 10.1.2.1
R1 after R2 RIP
R1# show ip route
10.0.0.0/24 is subnetted, 5 subnets
R 10.1.1.0 [120/1] via 10.1.2.1, 00:00:06, Serial0/0/0
[120/1] via 10.1.3.1, 00:00:06, Serial0/0/1
from Corp
C 10.1.2.0 is directly connected, Serial0/0/0
C 10.1.3.0 is directly connected, Serial0/0/1
R 10.1.4.0 [120/1] via 10.1.2.1, 00:00:06, Serial0/0/0
[120/1] via 10.1.3.1, 00:00:06, Serial0/0/1
R 10.1.5.0 [120/1] via 10.1.2.1, 00:00:06, Serial0/0/0
[120/1] via 10.1.3.1, 00:00:06, Serial0/0/1
from Corp
172.16.0.0/24 is subnetted, 1 subnets
S 172.16.10.0 [150/0] via 10.1.3.1
C 192.168.10.0/24 is directly connected, FastEthernet0/0
C 192.168.20.0/24 is directly connected, FastEthernet0/1
R 192.168.30.0/24 [120/2] via 10.1.3.1, 00:00:06, Serial0/0/1
[120/2] via 10.1.2.1, 00:00:06, Serial0/0/0
R 192.168.40.0/24 [120/2] via 10.1.2.1, 00:00:06, Serial0/0/0
[120/2] via 10.1.3.1, 00:00:06, Serial0/0/1
from R2 via Corp
Now to set RIP on R3
R3(config)# router rip
R3(config-router)# network 10.0.0.0
R3(config-router)# network 172.16.0.0
note that R3 is our only router with "gateway of last resort" set because we set a default route instead of static routes
As a result, we only see directly connected routes listed, along with a single "S*" for the default gateway
R3 before RIP
R3# show ip route
Gateway of last resort is 10.1.5.1 to network 0.0.0.0
10.0.0.0/8 is variably subnetted, 2 subnets, 2 masks
C 10.1.5.0/24 is directly connected, FastEthernet0/0
L 10.1.5.2/32 is directly connected, FastEthernet0/0
172.16.0.0/16 is variably subnetted, 2 subnets, 2 masks
C 172.16.10.0/24 is directly connected, Dot11Radio0/0/0
L 172.16.10.1/32 is directly connected, Dot11Radio0/0/0
S* 0.0.0.0/0 [1/0] via 10.1.5.1
R3 after RIP
R3# show ip route
Gateway of last resort is 10.1.5.1 to network 0.0.0.0
-------------------------------------------------------------
10.0.0.0/8 is variably subnetted, 6 subnets, 2 masks
R 10.1.1.0/24 [120/1] via 10.1.5.1, 00:00:21, FastEthernet0/0
R 10.1.2.0/24 [120/1] via 10.1.5.1, 00:00:21, FastEthernet0/0
R 10.1.3.0/24 [120/1] via 10.1.5.1, 00:00:21, FastEthernet0/0
R 10.1.4.0/24 [120/1] via 10.1.5.1, 00:00:21, FastEthernet0/0
from Corp
C 10.1.5.0/24 is directly connected, FastEthernet0/0
L 10.1.5.2/32 is directly connected, FastEthernet0/0
-------------------------------------------------------------
172.16.0.0/16 is variably subnetted, 2 subnets, 2 masks
C 172.16.10.0/24 is directly connected, Dot11Radio0/0/0
L 172.16.10.1/32 is directly connected, Dot11Radio0/0/0
R 192.168.10.0/24 [120/2] via 10.1.5.1, 00:00:21, FastEthernet0/0
R 192.168.20.0/24 [120/2] via 10.1.5.1, 00:00:21, FastEthernet0/0
From R1 via Corp
R 192.168.30.0/24 [120/2] via 10.1.5.1, 00:00:21, FastEthernet0/0
R 192.168.40.0/24 [120/2] via 10.1.5.1, 00:00:21, FastEthernet0/0
From R2 via Corp
S* 0.0.0.0/0 [1/0] via 10.1.5.1
Corp before R3 RIP
Corp# show ip route
10.0.0.0/8 is variably subnetted, 10 subnets, 2 masks
C 10.1.1.0/24 is directly connected, Vlan1
L 10.1.1.1/32 is directly connected, Vlan1
C 10.1.2.0/24 is directly connected, Serial0/0/0
L 10.1.2.1/32 is directly connected, Serial0/0/0
C 10.1.3.0/24 is directly connected, Serial0/0/1
L 10.1.3.1/32 is directly connected, Serial0/0/1
C 10.1.4.0/24 is directly connected, Serial0/1/0
L 10.1.4.1/32 is directly connected, Serial0/1/0
C 10.1.5.0/24 is directly connected, FastEthernet0/0
L 10.1.5.1/32 is directly connected, FastEthernet0/0
172.16.0.0/24 is subnetted, 1 subnets
S 172.16.10.0/24 [150/0] via 10.1.5.2
R 192.168.10.0/24 [120/1] via 10.1.2.2, 00:00:26, Serial0/0/0
[120/1] via 10.1.3.2, 00:00:26, Serial0/0/1
R 192.168.20.0/24 [120/1] via 10.1.2.2, 00:00:26, Serial0/0/0
[120/1] via 10.1.3.2, 00:00:26, Serial0/0/1
from R1 via corp
R 192.168.30.0/24 [120/1] via 10.1.4.2, 00:00:21, Serial0/1/0
R 192.168.40.0/24 [120/1] via 10.1.4.2, 00:00:21, Serial0/1/0
from R2 via corp
Corp after R3 RIP
Corp# show ip route
10.0.0.0/8 is variably subnetted, 10 subnets, 2 masks
C 10.1.1.0/24 is directly connected, Vlan1
L 10.1.1.1/32 is directly connected, Vlan1
C 10.1.2.0/24 is directly connected, Serial0/0/0
L 10.1.2.1/32 is directly connected, Serial0/0/0
C 10.1.3.0/24 is directly connected, Serial0/0/1
L 10.1.3.1/32 is directly connected, Serial0/0/1
C 10.1.4.0/24 is directly connected, Serial0/1/0
L 10.1.4.1/32 is directly connected, Serial0/1/0
C 10.1.5.0/24 is directly connected, FastEthernet0/0
L 10.1.5.1/32 is directly connected, FastEthernet0/0
172.16.0.0/16 is variably subnetted, 2 subnets, 2 masks
R 172.16.0.0/16 [120/1] via 10.1.5.2, 00:00:13, FastEthernet0/0
S 172.16.10.0/24 [150/0] via 10.1.5.2
from R3
R 192.168.10.0/24 [120/1] via 10.1.3.2, 00:00:13, Serial0/0/1
[120/1] via 10.1.2.2, 00:00:13, Serial0/0/0
R 192.168.20.0/24 [120/1] via 10.1.3.2, 00:00:13, Serial0/0/1
[120/1] via 10.1.2.2, 00:00:13, Serial0/0/0
from R1 via corp
R 192.168.30.0/24 [120/1] via 10.1.4.2, 00:00:24, Serial0/1/0
R 192.168.40.0/24 [120/1] via 10.1.4.2, 00:00:24, Serial0/1/0
from R2 via corp
R2 before R3 RIP
R2# show ip route
10.0.0.0/24 is subnetted, 5 subnets
R 10.1.1.0 [120/1] via 10.1.4.1, 00:00:15, Serial0/0/0
R 10.1.2.0 [120/1] via 10.1.4.1, 00:00:15, Serial0/0/0
R 10.1.3.0 [120/1] via 10.1.4.1, 00:00:15, Serial0/0/0
from Corp
C 10.1.4.0 is directly connected, Serial0/0/0
R 10.1.5.0 [120/1] via 10.1.4.1, 00:00:15, Serial0/0/0
from Corp
172.16.0.0/24 is subnetted, 1 subnets
S 172.16.10.0 [150/0] via 10.1.4.1
R 192.168.10.0/24 [120/2] via 10.1.4.1, 00:00:15, Serial0/0/0
R 192.168.20.0/24 [120/2] via 10.1.4.1, 00:00:15, Serial0/0/0
from R1 via Corp
C 192.168.30.0/24 is directly connected, FastEthernet0/0
C 192.168.40.0/24 is directly connected, FastEthernet0/1
R2 after R3 RIP
R2# show ip route
10.0.0.0/24 is subnetted, 5 subnets
R 10.1.1.0 [120/1] via 10.1.4.1, 00:00:20, Serial0/0/0
R 10.1.2.0 [120/1] via 10.1.4.1, 00:00:20, Serial0/0/0
R 10.1.3.0 [120/1] via 10.1.4.1, 00:00:20, Serial0/0/0
from Corp
C 10.1.4.0 is directly connected, Serial0/0/0
R 10.1.5.0 [120/1] via 10.1.4.1, 00:00:20, Serial0/0/0
from Corp
172.16.0.0/16 is variably subnetted, 2 subnets, 2 masks
R 172.16.0.0/16 [120/2] via 10.1.4.1, 00:00:20, Serial0/0/0
S 172.16.10.0/24 [150/0] via 10.1.4.1
from R3 via Corp
R 192.168.10.0/24 [120/2] via 10.1.4.1, 00:00:20, Serial0/0/0
R 192.168.20.0/24 [120/2] via 10.1.4.1, 00:00:20, Serial0/0/0
from R1 via Corp
C 192.168.30.0/24 is directly connected, FastEthernet0/0
C 192.168.40.0/24 is directly connected, FastEthernet0/1
R1 before R3 RIP
R1# show ip route
10.0.0.0/24 is subnetted, 5 subnets
R 10.1.1.0 [120/1] via 10.1.2.1, 00:00:04, Serial0/0/0
[120/1] via 10.1.3.1, 00:00:04, Serial0/0/1
C 10.1.2.0 is directly connected, Serial0/0/0
C 10.1.3.0 is directly connected, Serial0/0/1
R 10.1.4.0 [120/1] via 10.1.2.1, 00:00:04, Serial0/0/0
[120/1] via 10.1.3.1, 00:00:04, Serial0/0/1
R 10.1.5.0 [120/1] via 10.1.2.1, 00:00:04, Serial0/0/0
[120/1] via 10.1.3.1, 00:00:04, Serial0/0/1
from Corp
172.16.0.0/24 is subnetted, 1 subnets
S 172.16.10.0 [150/0] via 10.1.3.1
C 192.168.10.0/24 is directly connected, FastEthernet0/0
C 192.168.20.0/24 is directly connected, FastEthernet0/1
R 192.168.30.0/24 [120/2] via 10.1.2.1, 00:00:04, Serial0/0/0
[120/2] via 10.1.3.1, 00:00:04, Serial0/0/1
R 192.168.40.0/24 [120/2] via 10.1.2.1, 00:00:04, Serial0/0/0
[120/2] via 10.1.3.1, 00:00:04, Serial0/0/1
from R2 via Corp
R1 after R3 RIP
R1# show ip route
10.0.0.0/24 is subnetted, 5 subnets
R 10.1.1.0 [120/1] via 10.1.3.1, 00:00:03, Serial0/0/1
[120/1] via 10.1.2.1, 00:00:03, Serial0/0/0
C 10.1.2.0 is directly connected, Serial0/0/0
C 10.1.3.0 is directly connected, Serial0/0/1
R 10.1.4.0 [120/1] via 10.1.3.1, 00:00:03, Serial0/0/1
[120/1] via 10.1.2.1, 00:00:03, Serial0/0/0
R 10.1.5.0 [120/1] via 10.1.3.1, 00:00:03, Serial0/0/1
[120/1] via 10.1.2.1, 00:00:03, Serial0/0/0
from Corp
172.16.0.0/16 is variably subnetted, 2 subnets, 2 masks
R 172.16.0.0/16 [120/2] via 10.1.3.1, 00:00:03, Serial0/0/1
[120/2] via 10.1.2.1, 00:00:03, Serial0/0/0
S 172.16.10.0/24 [150/0] via 10.1.3.1
from R3 via Corp
C 192.168.10.0/24 is directly connected, FastEthernet0/0
C 192.168.20.0/24 is directly connected, FastEthernet0/1
R 192.168.30.0/24 [120/2] via 10.1.3.1, 00:00:03, Serial0/0/1
[120/2] via 10.1.2.1, 00:00:03, Serial0/0/0
R 192.168.40.0/24 [120/2] via 10.1.3.1, 00:00:03, Serial0/0/1
[120/2] via 10.1.2.1, 00:00:03, Serial0/0/0
from R2 via Corp
Verifying Configurations
in addition to
show ip route
we can also use
show ip protocols
and
debug rip ip
Corp# show ip protocols
Routing Protocol is "rip"
Sending updates every 30 seconds, next due in 11 seconds
Invalid after 180 seconds, hold down 180, flushed after 240
Outgoing update filter list for all interfaces is not set
Incoming update filter list for all interfaces is not set
Redistributing: rip
Default version control: send version 1, receive any version
Interface Send Recv Triggered RIP Key-chain
Vlan1 1 2 1
FastEthernet0/0 1 2 1
Serial0/0/1 1 2 1
Serial0/1/0 1 2 1
Serial0/0/0 1 2 1
Automatic network summarization is in effect
Maximum path: 4
Routing for Networks:
10.0.0.0
Passive Interface(s):
Routing Information Sources:
Gateway Distance Last Update
10.1.5.2 120 00:00:00
10.1.3.2 120 00:00:10
10.1.2.2 120 00:00:10
10.1.4.2 120 00:00:20
Distance: (default is 120)
R3# debug ip rip
R3#RIP: received v1 update from 10.1.5.1 on FastEthernet0/0
10.1.1.0 in 1 hops
10.1.2.0 in 1 hops
10.1.3.0 in 1 hops
10.1.4.0 in 1 hops
192.168.10.0 in 2 hops
192.168.20.0 in 2 hops
192.168.30.0 in 2 hops
192.168.40.0 in 2 hops
R3#RIP: sending v1 update to 255.255.255.255 via Dot11Radio0/0/0 (172.16.10.1)
RIP: build update entries
network 10.0.0.0 metric 1
network 192.168.10.0 metric 3
network 192.168.20.0 metric 3
network 192.168.30.0 metric 3
network 192.168.40.0 metric 3
RIP: sending v1 update to 255.255.255.255 via FastEthernet0/0 (10.1.5.2)
RIP: build update entries
network 172.16.0.0 metric 1
output loops until manually disabled..............
R3# undebug all
All possible debugging has been turned off
Note that due to the Split Horizon rule, R3 is not sending all of it's known RIP data to Corp.
It is sending all known RIP data out of the wifi interface (even there though there's no router that way),
but it is ONLY sending data about the wifi network back to Corp; data that Corp doesnt already have
Now lets look at some examples with sample routers..
I got hung up on these two examples because I found the wording to be a bit confusing. Also there was subnetting involved that I was able to figure out, but threw me at first
First source of confusion- we have two seperate examples, and I was mixing them up.
The examples are:
Use the debug ip rip command to both:
discover a problem
and figure out how RIP was configured on a router from a different sample network
The conclusion regarding 'figuring out how RIP is configured' on this router, is that RIP networks are set as 10.0.0.0 and 172.16.0.0.
We determined that we are not the 'first source' of info on the 192.168.1.0 nertwork, since it is a metric of 2. We are sending out RIP data on that network, but that RIP data is made availbale to us via another router.
I also got tripped up on the fact that RA is sending out S0/0 which corresponds 10.0.8.1, and then receiving on the same interface S0/0 from an ip address of 10.0.15.0 on the other side of the link
I was able to determine that these two address are actually on the same subnet. My initial assumption was that the network address for the link is 10.0.0.0.
The problem doesn't give the subnet mask- I guessed it as /20 by using a 16 block since we can see that the third octet seems to move in 8's
if the network starts at 10.0.0.0 and we use /20 with 16 block, we would indeed have a last host address of 10.0.15.254, so 10.0.15.2 would be a valid host.
So there was a twist to this problem which needed subnetting to solve. It wasnt particulary releveant to the subject of RIP, but I was curious why the address on the other side of that link looked so strange.
The problem also points out that we can determine there are 'at least' two routers participating in RIP here since we are sending RIP data out two interfaces but only receiving RIP data on one interface. I'm unclear on why its worded this way; we know we are a RIP router- the fact that we are receiving data on one interface would suggest there is 'at least one more' RIP router out there.
that's it for this example. Back to the original statement-
Use the debug ip rip command to both discover a problem and figure out
how RIP was configured on a router from a different sample network
We just 'figured out how RIP was configured on a router'.. The second example is regarding 'discovering a problem', although it is mentioned first.
The second example will use debug ip rip and show ip route to find a problem with the network
it looks like RIP data for 172.16.20.0 was received on S0/0, and then that interface was bumped out of the routing table entry for that network in favor of a static route.
ok, moving on now to RIP V2
RIP V2
enable it on all four routers
Corp(config)
router rip
Corp(config-router) version 2
Corp(config-router) version 2
R1(config)
router rip
R1(config-router) version 2
R1(config-router) version 2
R2(config)
router rip
R2(config-router) version 2
R2(config-router) version 2
R3(config)
router rip
R3(config-router) version 2
R3(config-router) version 2
We'll use R1 to compare RIPv1 and RIPv2
RIPv1
R1(config) debug ip rip
R1#RIP: sending v1 update to 255.255.255.255 via FastEthernet0/0 (192.168.10.1)
RIP: build update entries
network 10.0.0.0 metric 1
network 172.16.0.0 metric 3
network 192.168.20.0 metric 1
network 192.168.30.0 metric 3
network 192.168.40.0 metric 3
RIP: sending v1 update to 255.255.255.255 via FastEthernet0/1 (192.168.20.1)
RIP: build update entries
network 10.0.0.0 metric 1
network 172.16.0.0 metric 3
network 192.168.10.0 metric 1
network 192.168.30.0 metric 3
network 192.168.40.0 metric 3
RIP: sending v1 update to 255.255.255.255 via Serial0/0/0 (10.1.2.2)
RIP: build update entries
network 10.1.3.0 metric 1
network 192.168.10.0 metric 1
network 192.168.20.0 metric 1
RIP: sending v1 update to 255.255.255.255 via Serial0/0/1 (10.1.3.2)
RIP: build update entries
network 10.1.2.0 metric 1
network 192.168.10.0 metric 1
network 192.168.20.0 metric 1
RIPv2
R1(config) debug ip rip
R1#RIP: sending v2 update to 224.0.0.9 via FastEthernet0/0 (192.168.10.1)
RIP: build update entries
10.0.0.0/8 via 0.0.0.0, metric 1, tag 0
172.16.0.0/16 via 0.0.0.0, metric 3, tag 0
192.168.20.0/24 via 0.0.0.0, metric 1, tag 0
192.168.30.0/24 via 0.0.0.0, metric 3, tag 0
192.168.40.0/24 via 0.0.0.0, metric 3, tag 0
RIP: sending v2 update to 224.0.0.9 via FastEthernet0/1 (192.168.20.1)
RIP: build update entries
10.0.0.0/8 via 0.0.0.0, metric 1, tag 0
172.16.0.0/16 via 0.0.0.0, metric 3, tag 0
192.168.10.0/24 via 0.0.0.0, metric 1, tag 0
192.168.30.0/24 via 0.0.0.0, metric 3, tag 0
192.168.40.0/24 via 0.0.0.0, metric 3, tag 0
RIP: sending v2 update to 224.0.0.9 via Serial0/0/0 (10.1.2.2)
RIP: build update entries
10.1.3.0/24 via 0.0.0.0, metric 1, tag 0
192.168.10.0/24 via 0.0.0.0, metric 1, tag 0
192.168.20.0/24 via 0.0.0.0, metric 1, tag 0
RIP: sending v2 update to 224.0.0.9 via Serial0/0/1 (10.1.3.2)
RIP: build update entries
10.1.2.0/24 via 0.0.0.0, metric 1, tag 0
192.168.10.0/24 via 0.0.0.0, metric 1, tag 0
192.168.20.0/24 via 0.0.0.0, metric 1, tag 0
R1(config) show ip protocols
Routing Protocol is "rip"
Sending updates every 30 seconds, next due in 13 seconds
Invalid after 180 seconds, hold down 180, flushed after 240
Outgoing update filter list for all interfaces is not set
Incoming update filter list for all interfaces is not set
Redistributing: rip
Default version control: send version 2, receive 2
Interface Send Recv Triggered RIP Key-chain
FastEthernet0/0 2 2
FastEthernet0/1 2 2
Serial0/0/0 2 2
Serial0/0/1 2 2
Automatic network summarization is in effect
Maximum path: 4
Routing for Networks:
10.0.0.0
192.168.10.0
192.168.20.0
Passive Interface(s):
Routing Information Sources:
Gateway Distance Last Update
10.1.3.1 120 00:00:21
10.1.2.1 120 00:00:21
Distance: (default is 120)
final task of this chapter
Enable a default route out to the internet , and advertise via RIP
R3(config)# interface s0/1/0 (this is only for example, so I am not adding a serial card to R3)
R3(config-if)# ip addr 172.16.10.5 255.255.255.252
R3(config-if)# exit
R3(config)# ip route 0.0.0.0 0.0.0.0 s0/0
R3(config)# ip default-network 172.16.0.0 tells other routers via RIP that default WAN route is through R3
Enable a default route out to the internet , and advertise via RIP
R3(config)# interface s0/1/0 (this is only for example, so I am not adding a serial card to R3)
R3(config-if)# ip addr 172.16.10.5 255.255.255.252
R3(config-if)# exit
R3(config)# ip route 0.0.0.0 0.0.0.0 s0/0
R3(config)# ip default-network 172.16.0.0 tells other routers via RIP that default WAN route is through R3
Chapter 8 Exam Essentials IP Routing
1. Describe the Basic IP routing process
frame changes at each hop, but packet doesnt change EXCEPT that the TTL field in the IP header decrements
2. List the information required by a router to successfully route packets
destination IP address, location of other routers, possible routers to all remote networks,
the best route to each network, how to maintain and maintain routing info
3. Describe how MAC addresses are used during the routing process
a MAC will never pass a router interface. MACs will change between router interfaces
4. View and interpret the routing table of a router
use show ip route to see the table
a "C" indicates directly connected, an "R" indicates RIP provided the route info, "S" means static
5. differentiate the three types of routing
static- manually configured
dynamic- routers automatically share info via protocol
default- a special route is configured for all traffic without a more specific destination network found in the table
6. Compare and contrast static and dynamic routing
static routing creates no routing update traffic which means less overhead on the routers and links- but it must be
configured manually and can't react if links are lost.
dynamic routing creates update traffic, but it can react to outages and choose the best route when multiple routes exist to the same network
7. Configure static routes at the CLI
route [dest network] [mask] [next hop address OR exit interface] [admin distance] [permanent]
Ex:
Corp(config)#
ip route 192.168.10.0 255.255.255.0 10.1.2.2 150
8. Create a default route
ip route 0.0.0.0 0.0.0.0 [ip address OR exit interface]
Ex:
R3(config)#
ip route 0.0.0.0 0.0.0.0 10.1.5.1 (ingress at Corp router- use if R3 cant identify route)
9. Understand administrative distance and its role in the selection of the best route
an integer from 0 (most trusted) to 255 (no traffic will pass via this route).
All routing protocols are assigned an AD but it can be changed at the CLI
10. Differentiate distance-vector, link-state, and hybrid routing protocols
distance vector- based on hop count (RIP)
link-state- multiple factors such as bandwidth and delay
hybrid- uses both
11. List mechanisms used to prevent routing loops in the network
max hop count, split horizon, route poisoning, holddown counters
12. Describe the counts used the operation of RIP
route update timer- (30) interval between routing updates
route invalid timer- (180, update x 3) before a route is determined invalid
holddown timer-(180) time info is supressed when a link is lost
route flush timer- (240) seconds before invalid and removal
13. Configure RIP routing
router rip
network x.x.x.x
the network(s) you want to advertise from your router. It only works if the other router has RIP enabled.
By enabling RIP, you are able to RECEIVE RIP data from other RIP routers.
by specifying a network, you are SENDING RIP data on that network
14. Identify commands used to verify RIP routing
show ip route will provide contents of the routing table with codes (R, C, S)
debug ip rip will show RIP updates being sent and received
15. Describe the differences between RIPv1 and RIPv2
RIPv1 sends a broadcast (255.255.255.255) every 30 seconds and has an AD of 120.
RIPv1 is classful only, does not send any mask info. No authentication between routers.
RIPv2 sends multicasts (224.0.0.9) every 30 seconds and sends mask info, which allows it to support classless networking, RIPv2 also supports
autentication between routers.
Chapter 8 Written Lab 8.0
1. At the appropriate prompt, create a static route to network 172.16.10.0/24 with a next-hop
gateway of 172.16.20.1 and an administrative distance of 150.
Router(config)#
ip route 172.16.10.0 255.255.255.0 172.16.20.1 150
2. When a PC sends a packet to another PC in a remote network, what destination IP address and MAC address will
be in the frame that it sends to it's default gateway?
the gateway interface MAC and the remote PC's IP
3. At the appropriate prompt, create a default route to 172.16.40.1
Router(config)#
ip route 0.0.0.0 0.0.0.0 172.16.40.1
"to" is the wrong word.. we are going TO any route VIA 172.16.40.1
4. If you are using default routing in a classless environment, what command must also be used?
Router(config)#
ip classless
5. On which type of network is a default route most beneficial?
stub
6. At the appropriate prompt, display the routing table on your router
Router#
show ip route
7. When creating a static or default route, you dont have to use the next-hop ip address;
you can instead use the ____________
exit interface
8. True/False: To reach a destination host, you must know the MAC address of the remote host
false, you need the MAC of your router
9. True/False: To reach a destination host, you must know the IP address of the remote host
true
10. At the appropriate prompt, execute the command required on a DCE serial interface that is not required
on a DTE serial interface
Router(config-if)#
clock rate X
11. At the appropriate prompt, enable RIP routing on the interface with the IP address 10.0.0.1/24
Router(config)#
router rip
Router(config-router)#
network 10.0.0.0
RIPv1 is CLASSFUL only... use the classful mask based on the first octet given
12. At the appropriate prompt, prevent a router from propagating IP information out serial 1
Router(config)#
router rip
Router(config-router)#
passive-interface S0/1
can receive RIP data but will not send
13. What routing loop prevention mechanism sends out a maximum hop count as soon as a link fails?
route poisoning
14. What routing loop prevention mechanism suppresses the resending of routing information to an interface
through which it was received?
split horizon
15. At the appropriate prompt display RIP routing updates as they are sent and received on the router
to the console session
Router#
debug ip rip
to turn it off:
Router#
undebug all
Chapter 8 Hands-on Labs
For these labs we will need a network with three routers.
Lab 8.1 Creating Static routes
first set the interfaces, then program the static routes
LabA(config)#
int s0/0/0
LabA(config-if)#
ip addr 172.16.20.1
LabA(config-if)#
int f0/0
LabA(config-if)#
ip addr 172.16.10.1
-----------------------------------------------------------------
LabA(config)#
ip route 172.16.30.0 255.255.255.0 172.16.20.2
LabA(config)#
ip route 172.16.40.0 255.255.255.0 172.16.20.2
LabB(config)#
int s0/0/0
LabB(config-if)#
ip addr 172.16.20.2
LabB(config-if)#
int s0/0/1
LabB(config-if)#
ip addr 172.16.30.1
-----------------------------------------------------------------
LabB(config)#
ip route 172.16.10.0 255.255.255.0 172.16.20.1
LabB(config)#
ip route 172.16.40.0 255.255.255.0 172.16.30.2
LabC(config)#
int s0/0/0
LabC(config-if)#
ip addr 172.16.30.2
LabC(config-if)#
int f0/0
LabC(config-if)#
ip addr 172.16.40.1
-----------------------------------------------------------------
LabC(config)#
ip route 172.16.10.0 255.255.255.0 172.16.30.1
LabC(config)#
ip route 172.16.20.0 255.255.255.0 172.16.30.1
Lab 8.2 RIP Configuration
remove the static routes, enable and configure RIP with the classful network id that covers the routes you want to advertise
LabA(config)#
no ip route 172.16.30.0 255.255.255.0 172.16.20.2
LabA(config)#
no ip route 172.16.40.0 255.255.255.0 172.16.20.2
LabA(config)#
router rip
LabA(config-router)#
network 172.16.0.0
LabA(config-router)#
do show ip route
Gateway of last resort is not set
172.16.0.0/16 is variably subnetted, 5 subnets, 2 masks
C 172.16.10.0/24 is directly connected, FastEthernet0/0
L 172.16.10.1/32 is directly connected, FastEthernet0/0
C 172.16.20.0/24 is directly connected, Serial0/0/0
L 172.16.20.1/32 is directly connected, Serial0/0/0
R 172.16.30.0/24 [120/1] via 172.16.20.2, 00:00:07, Serial0/0/0
from Lab B
LabB(config)#
no ip route 172.16.10.0 255.255.255.0 172.16.20.1
LabB(config)#
no ip route 172.16.40.0 255.255.255.0 172.16.30.2
LabB(config)#
router rip
LabB(config-router)#
network 172.16.0.0
LabB(config-router)#
do show ip route
Gateway of last resort is not set
172.16.0.0/16 is variably subnetted, 5 subnets, 2 masks
R 172.16.10.0/24 [120/1] via 172.16.20.1, 00:00:13, Serial0/0/0
from LabA
C 172.16.20.0/24 is directly connected, Serial0/0/0
L 172.16.20.2/32 is directly connected, Serial0/0/0
C 172.16.30.0/24 is directly connected, Serial0/0/1
L 172.16.30.1/32 is directly connected, Serial0/0/1
LabC(config)#
no ip route 172.16.10.0 255.255.255.0 172.16.30.1
LabC(config)#
no ip route 172.16.20.0 255.255.255.0 172.16.30.1
LabC(config)#
router rip
LabC(config-router)#
network 172.16.0.0
LabC(config-router)#
do show ip route
Gateway of last resort is not set
172.16.0.0/16 is variably subnetted, 3 subnets, 2 masks
R 172.16.20.0/24 [120/1] via 172.16.30.1, 00:00:05, Serial0/0/0
from LabB
C 172.16.30.0/24 is directly connected, Serial0/0/0
L 172.16.30.2/32 is directly connected, Serial0/0/0
Chapter 8 Review Questions
1. The Acme company uses a router named Gateway to connect to its ISP. The address of the ISP router is 206.143.5.2.
Which three commands could be configured on the gateway router to allow internet access to the entire network?
Set a default route:
Gateway(config)#
ip route 0.0.0.0 0.0.0.0 206.143.5.2 next hop IP
Gateway(config)#
ip route 0.0.0.0 0.0.0.0 S/0 exit interface instead of next hop IP
Gateway(config)#
ip default-network 206.143.5.0 next hop IP
2. What command will prevent RIP routing updates from exiting an interface but will sill allow the interface to receive RIP updates?
Router(config-if)#
passive-interface
3. Which two statemnts are true about ip route 172.16.4.0 255.255.255.0 192.168.4.2?
the command establishes a static route
the default admin distance is used (since we didnt give an AD argument)
4. What two destination addresses will be used by HostA to send data to the HTTPS server as shown in the following network?
MAC of RouterA f0/0 interface
IP address of the server
5. Which two statements are true about this output?
RIP: received v1 update from 192.168.40.2 on S0/1
192.168.50.0 in 16 hops (inaccessible)
RIP: sending v1 update to 255.255.255.255 via F0/0 (192.168.30.1)
RIP: build update entries
network 192.168.20.0 metric 1
network 192.168.40.0 metric 1
network 192.168.50.0 metric 16
RIP: sending v1 update to 255.255.255.255 via S0/1 (192.168.40.1)
true:
there are at least two routers exchanging information
192.168.40.2 will be successful
FALSE
there are three interfaces on the router participating in this update
false because we only see two interfaces represented in the output: S0/1(twice) and F0/0
a ping to 192.168.50.1 will be successful
false because that route has a metric of 16; it's unreachable
6. Describe split horizon
will not advertise a route back the the same router it was learned from
7. Which would be true if HostA is trying to communicate to HostB and interface F0/0 of RouterC goes down, as shown in the graphic?
RouterC will send an ICMP 'destination unreachable type' message to inform HostA that HostB is unreachable
8. Which two statements are true regarding classless routing protocols?
VLSM is permitted
RIPv2 supports classless
9. Which two are true regarding distance-vector vs link-state?
Distance vector sends the whole routing table out all active interfaces(even if a router isnt on the other end)at periodic time intervals
Link-state sends updates containing the state of its own links to all routers in the inter-network
10. Which command display RIP routing updates?
debug ip rip
11. What does RIPv2 use to prvent routing loops?
split horizon stops an update from being send on the same interface it was received
holdown timers allow time for a network to become stable in the case of a flapping link
12. A network administrator views the output from the show ip route command. A network that is advertised
by both RIP and EIGRP appears in the routing table flagged an EIGRP route. Why is the RIP route to this network not used in this routing table?
EIGRP has a lower AD.
RIP=120
OSPP=110
IGRP=110
EIGRP=90
13. You type debug ip rip on your router console and see that 172.16.10.0 is being advertised to you with a metric of 16. What does this mean?
it is inaccessible. in RIP if you see a route advertised with a metric of 16, it's inaccessible
14. What metric does RIPv2 use to find the best path to the remote network?
distance aka hop count
15. The Corporate router receives an IP packet with a source IP address of 192.168.214.20 and a destination address of 192.168.22.3. Looking at the output from the Corp router,
what will the router do with this packet?
Corp# show ip route
[cut]
R 192.168.215.0 [120/2] via 192.168.20.2, Serail0/0
R 192.168.115.0 [120/1] via 192.168.20.0, Serial0/0
R 192.168.30.0 [120/1] via 192.168.20.2, Serial0/0
C 192.168.20.0 is directly connected, Serial0/0
C 192.168.214.0 is directly connected, FastEthernet0/0
Since there is no route to that network, the router will discard the packet and send an ICMP destination unreachable message out F0/0 back the the source network
16. If your routing table has a static, a RIP and an EIGRP route to the same network, which route will be used by default?
Static routes have an admin distance of 1 by default. Unless you change it, a static route will always be used over any other
dynamically learned route.
17. You have the following routing table. Which network will NOT be placed in the neighbor routing table?
R 192.168.30.0/24 [120/1] via 192.168.40.1, Serial 0
C 192.168.40.0/24 is directly connected, Serial 0
172.16.0.0/2 is subnetted, 1 subnets
C 172.16.30.0 is directly connected, Loopback0
R 192.168.20.0/24 [120/1] via 192.168.40.1, Serial 0
R 10.0.0.0/8 [120/15] via 192.168.40.1, Serial 0
C 192.168.50.0/24 is directly connected, Ethernet 0
10.0.0.0 cant be placed in neighboring routing table because it is at 15 hops. 16 hops is invalid in RIP
18. Two connected routers are configured only with RIP. What will be the result when a router receives a routing update that contains a
higher-cost path to a network already in it's routing table?
The router will ignore the update because it is higher cost. When a routing update is received, the router first checks the AD and always chooses
the route with the lowest AD.
19.Which is true about route poisoning?
The router sets the metric for a downed link to "infinity".
20. Which is true about RIPv2?
it has all the same timers as RIPv1
------------------------------------------------------------------------------
END CHAPTER 8
54 hours 1-28 thru 2-14-22
original total 143 hours
11.5 hours review 12-23,24,26-22
review total hours 32
book page 428/822
avg 20 min/page (reading and exercises/labs)
Chapter 9 EIGRP and OSPF
pages 427-502, start 2-14-22-M
What is EIGRP?
Note it's not officially on CCNA 200-301 but it is still important to learn
Enhanced IGRP is a classless, enchanced distance vector protocol that uses the concept of an autonomous system to describe
the set of contigous routers that run the same routing protocol and share routing information.
Features:
Support for IP and IPv6 via protocol-dependent modules (seperate routing tables)
Considered classless
Support for summaries and discontiguous networks
Eficient neighbor discovery
communication via RTP- Reliable Transport Protocol
best path selection via Diffusing Updae Algorithm DUAL
Cisco considers EIGRP a "distance-vector" routing protocol
or an "advanced distance-vector" protocol
or a "hybrid" protocol
Configuring EIGRP on our network
------------------------------------------------------------------------------------------------------------------------------------
Corp(config)#
router eigrp ?
<1-65535> Autonomous system number
Corp(config)#
router eigrp 10
R2(config-router)#
network 10.0.0.0
after eigrp on R1- links from Corp to R1 are up
%DUAL-5-NBRCHANGE: IP-EIGRP 10: Neighbor 10.1.3.2 (Serial0/0/1) is up: new adjacency
%DUAL-5-NBRCHANGE: IP-EIGRP 10: Neighbor 10.1.2.2 (Serial0/0/0) is up: new adjacency
after eigrp on R2- link from Corp to R2 is up
%DUAL-5-NBRCHANGE: IP-EIGRP 10: Neighbor 10.1.4.2 (Serial0/1/0) is up: new adjacency
after eigrp on R3- link from Corp to R3 is up
%DUAL-5-NBRCHANGE: IP-EIGRP 10: Neighbor 10.1.5.2 (FastEthernet0/0) is up: new adjacency
------------------------------------------------------------------------------------------------------------------------------------
R1(config)#
router eigrp 10
R1(config-router)#
network 10.0.0.0
after eigrp on R1- link from R1 to Corp is up
%DUAL-5-NBRCHANGE: IP-EIGRP 10: Neighbor 10.1.3.1 (Serial0/0/1) is up: new adjacency
%DUAL-5-NBRCHANGE: IP-EIGRP 10: Neighbor 10.1.2.1 (Serial0/0/0) is up: new adjacency
R1(config-router)#
network 192.168.10.0
R1(config-router)#
network 192.168.20.0
------------------------------------------------------------------------------------------------------------------------------------
R2(config)#
router eigrp 10
R2(config-router)#
network 10.0.0.0
after eigrp on R2- link from R2 to Corp is up
%DUAL-5-NBRCHANGE: IP-EIGRP 10: Neighbor 10.1.4.1 (Serial0/0/0) is up: new adjacency
R1(config-router)#
network 192.168.30.0
R1(config-router)#
network 192.168.40.0
------------------------------------------------------------------------------------------------------------------------------------
R3(config)#
router eigrp 10
R3(config-router)#
network 10.0.0.0
after eigrp on R3- link from R3 to Corp is up
%DUAL-5-NBRCHANGE: IP-EIGRP 10: Neighbor 10.1.5.1 (FastEthernet0/0) is up: new adjacency
R1(config-router)#
network 172.16.0.0
------------------------------------------------------------------------------------------------------------------------------------
Corp#
show ip route
Gateway of last resort is not set
Gateway of last resort is not set
10.0.0.0/8 is variably subnetted, 10 subnets, 2 masks
C 10.1.1.0/24 is directly connected, Vlan1
L 10.1.1.1/32 is directly connected, Vlan1
C 10.1.2.0/24 is directly connected, Serial0/0/0
L 10.1.2.1/32 is directly connected, Serial0/0/0
C 10.1.3.0/24 is directly connected, Serial0/0/1
L 10.1.3.1/32 is directly connected, Serial0/0/1
C 10.1.4.0/24 is directly connected, Serial0/1/0
L 10.1.4.1/32 is directly connected, Serial0/1/0
C 10.1.5.0/24 is directly connected, FastEthernet0/0
L 10.1.5.1/32 is directly connected, FastEthernet0/0
172.16.0.0/16 is variably subnetted, 2 subnets, 2 masks
R 172.16.0.0/16 [120/1] via 10.1.5.2, 00:00:17, FastEthernet0/0
D 172.16.10.0/24 [90/28160] via 10.1.5.2, 00:00:16, FastEthernet0/0
via R3
D 192.168.10.0/24 [90/2172416] via 10.1.2.2, 00:19:13, Serial0/0/0
[90/2172416] via 10.1.3.2, 00:19:13, Serial0/0/1
D 192.168.20.0/24 [90/2172416] via 10.1.3.2, 00:19:05, Serial0/0/1
[90/2172416] via 10.1.2.2, 00:19:05, Serial0/0/0
via R1
D 192.168.30.0/24 [90/2172416] via 10.1.4.2, 00:01:31, Serial0/1/0
D 192.168.40.0/24 [90/2172416] via 10.1.4.2, 00:01:08, Serial0/1/0
via R2
The "D" routes are for DUAL- Diffusing Update Algorithm, indicating they are EIGRP routes.
Note that we have RIP and EIGRP set currently
------------------------------------------------------------------------------------------------------------------------------------
R1#
show ip route
Gateway of last resort is not set
10.0.0.0/8 is variably subnetted, 6 subnets, 2 masks
D 10.0.0.0/8 is a summary, 00:25:28, Null0
D 10.1.1.0/24 [90/27769856] via 10.1.2.1, 00:31:33, Serial0/0/0
[90/27769856] via 10.1.3.1, 00:31:30, Serial0/0/1
via Corp
C 10.1.2.0/24 is directly connected, Serial0/0/0
C 10.1.3.0/24 is directly connected, Serial0/0/1
D 10.1.4.0/24 [90/2681856] via 10.1.2.1, 00:31:33, Serial0/0/0
[90/2681856] via 10.1.3.1, 00:31:30, Serial0/0/1
D 10.1.5.0/24 [90/2172416] via 10.1.2.1, 00:31:33, Serial0/0/0
[90/2172416] via 10.1.3.1, 00:31:30, Serial0/0/1
via Corp
172.16.0.0/16 is variably subnetted, 2 subnets, 2 masks
R 172.16.0.0/16 [120/2] via 10.1.2.1, 00:00:07, Serial0/0/0
[120/2] via 10.1.3.1, 00:00:07, Serial0/0/1
D 172.16.10.0/24 [90/2172416] via 10.1.2.1, 00:06:31, Serial0/0/0
[90/2172416] via 10.1.3.1, 00:06:31, Serial0/0/1
via Corp
C 192.168.10.0/24 is directly connected, FastEthernet0/0
C 192.168.20.0/24 is directly connected, FastEthernet0/1
D 192.168.30.0/24 [90/2684416] via 10.1.3.1, 00:07:46, Serial0/0/1
[90/2684416] via 10.1.2.1, 00:07:46, Serial0/0/0
D 192.168.40.0/24 [90/2684416] via 10.1.2.1, 00:07:23, Serial0/0/0
[90/2684416] via 10.1.3.1, 00:07:23, Serial0/0/1
via Corp
------------------------------------------------------------------------------------------------------------------------------------
R2#
show ip route
Gateway of last resort is not set
10.0.0.0/8 is variably subnetted, 6 subnets, 2 masks
D 10.0.0.0/8 is a summary, 00:13:09, Null0
D 10.1.1.0/24 [90/27769856] via 10.1.4.1, 00:36:53, Serial0/0/0
D 10.1.2.0/24 [90/2681856] via 10.1.4.1, 00:36:53, Serial0/0/0
D 10.1.3.0/24 [90/2681856] via 10.1.4.1, 00:36:53, Serial0/0/0
via Corp
C 10.1.4.0/24 is directly connected, Serial0/0/0
D 10.1.5.0/24 [90/2172416] via 10.1.4.1, 00:36:53, Serial0/0/0
via Corp
172.16.0.0/16 is variably subnetted, 2 subnets, 2 masks
R 172.16.0.0/16 [120/2] via 10.1.4.1, 00:00:23, Serial0/0/0
D 172.16.10.0/24 [90/2172416] via 10.1.4.1, 00:11:54, Serial0/0/0
via Corp
D 192.168.10.0/24 [90/2684416] via 10.1.4.1, 00:30:51, Serial0/0/0
D 192.168.20.0/24 [90/2684416] via 10.1.4.1, 00:30:43, Serial0/0/0
via Corp
C 192.168.30.0/24 is directly connected, FastEthernet0/0
C 192.168.40.0/24 is directly connected, FastEthernet0/1
------------------------------------------------------------------------------------------------------------------------------------
R3#
show ip route
Gateway of last resort is 10.1.5.1 to network 0.0.0.0
10.0.0.0/8 is variably subnetted, 6 subnets, 2 masks
D 10.1.1.0/24 [90/25628160] via 10.1.5.1, 00:37:20, FastEthernet0/0
D 10.1.2.0/24 [90/2172416] via 10.1.5.1, 00:37:15, FastEthernet0/0
D 10.1.3.0/24 [90/2172416] via 10.1.5.1, 00:37:20, FastEthernet0/0
D 10.1.4.0/24 [90/2172416] via 10.1.5.1, 00:37:20, FastEthernet0/0
via Corp
C 10.1.5.0/24 is directly connected, FastEthernet0/0
L 10.1.5.2/32 is directly connected, FastEthernet0/0
172.16.0.0/16 is variably subnetted, 2 subnets, 2 masks
C 172.16.10.0/24 is directly connected, Dot11Radio0/0/0
L 172.16.10.1/32 is directly connected, Dot11Radio0/0/0
D 192.168.10.0/24 [90/2174976] via 10.1.5.1, 00:31:10, FastEthernet0/0
D 192.168.20.0/24 [90/2174976] via 10.1.5.1, 00:31:02, FastEthernet0/0
via Corp and R1
D 192.168.30.0/24 [90/2174976] via 10.1.5.1, 00:13:28, FastEthernet0/0
D 192.168.40.0/24 [90/2174976] via 10.1.5.1, 00:13:05, FastEthernet0/0
via Corp and R2
S* 0.0.0.0/0 [1/0] via 10.1.5.1
------------------------------------------------------------------------------------------------------------------------------------
turn off auto summary on each router
------------------------------------------------------------------------------------------------------------------------------------
Corp(config)#
router eigrp 10
Corp(config-router)#
no auto-summary
------------------------------------------------------------------------------------------------------------------------------------
R1(config)#
router eigrp 10
R1(config-router)#
no auto-summary
------------------------------------------------------------------------------------------------------------------------------------
R2(config)#
router eigrp 10
R2(config-router)#
no auto-summary
------------------------------------------------------------------------------------------------------------------------------------
R3(config)#
router eigrp 10
R3(config-router)#
no auto-summary
------------------------------------------------------------------------------------------------------------------------------------
compare Corp before and after auto summary turned off
------------------------------------------------------------------------------------------------------------------------------------
auto summary on
Corp#
show ip route
Gateway of last resort is not set
10.0.0.0/8 is variably subnetted, 10 subnets, 2 masks
C 10.1.1.0/24 is directly connected, Vlan1
L 10.1.1.1/32 is directly connected, Vlan1
C 10.1.2.0/24 is directly connected, Serial0/0/0
L 10.1.2.1/32 is directly connected, Serial0/0/0
C 10.1.3.0/24 is directly connected, Serial0/0/1
L 10.1.3.1/32 is directly connected, Serial0/0/1
C 10.1.4.0/24 is directly connected, Serial0/1/0
L 10.1.4.1/32 is directly connected, Serial0/1/0
C 10.1.5.0/24 is directly connected, FastEthernet0/0
L 10.1.5.1/32 is directly connected, FastEthernet0/0
172.16.0.0/16 is variably subnetted, 2 subnets, 2 masks
R 172.16.0.0/16 [120/1] via 10.1.5.2, 00:00:17, FastEthernet0/0
D 172.16.10.0/24 [90/28160] via 10.1.5.2, 00:00:16, FastEthernet0/0
via R3
D 192.168.10.0/24 [90/2172416] via 10.1.2.2, 00:19:13, Serial0/0/0
[90/2172416] via 10.1.3.2, 00:19:13, Serial0/0/1
D 192.168.20.0/24 [90/2172416] via 10.1.3.2, 00:19:05, Serial0/0/1
[90/2172416] via 10.1.2.2, 00:19:05, Serial0/0/0
via R1
D 192.168.30.0/24 [90/2172416] via 10.1.4.2, 00:01:31, Serial0/1/0
D 192.168.40.0/24 [90/2172416] via 10.1.4.2, 00:01:08, Serial0/1/0
via R2
auto summary off
Corp#
show ip route
Gateway of last resort is not set
10.0.0.0/8 is variably subnetted, 10 subnets, 2 masks
C 10.1.1.0/24 is directly connected, Vlan1
L 10.1.1.1/32 is directly connected, Vlan1
C 10.1.2.0/24 is directly connected, Serial0/0/0
L 10.1.2.1/32 is directly connected, Serial0/0/0
C 10.1.3.0/24 is directly connected, Serial0/0/1
L 10.1.3.1/32 is directly connected, Serial0/0/1
C 10.1.4.0/24 is directly connected, Serial0/1/0
L 10.1.4.1/32 is directly connected, Serial0/1/0
C 10.1.5.0/24 is directly connected, FastEthernet0/0
L 10.1.5.1/32 is directly connected, FastEthernet0/0
172.16.0.0/16 is variably subnetted, 2 subnets, 2 masks
R 172.16.0.0/16 [120/1] via 10.1.5.2, 00:00:12, FastEthernet0/0
D 172.16.10.0/24 [90/28160] via 10.1.5.2, 00:45:29, FastEthernet0/0
via R3
D 192.168.10.0/24 [90/2172416] via 10.1.2.2, 00:01:08, Serial0/0/0
[90/2172416] via 10.1.3.2, 00:01:08, Serial0/0/1
D 192.168.20.0/24 [90/2172416] via 10.1.2.2, 00:01:08, Serial0/0/0
[90/2172416] via 10.1.3.2, 00:01:08, Serial0/0/1
via R1
D 192.168.30.0/24 [90/2172416] via 10.1.4.2, 00:00:46, Serial0/1/0
D 192.168.40.0/24 [90/2172416] via 10.1.4.2, 00:00:46, Serial0/1/0
via R2
We are still seeing an auto summarized route- 172.16.0.0 coming from R3.
The book discusses enabling EIGRP auto summary on all four routers- nothing is said about disabling it within RIP or turning off RIP.
RIP auto summarizes by default. We cant get rid of this auto summary route while RIP is on.
Moving on...
VERIFYING EIGRP
several commands available to verify and troubleshoot
show ip route
show the entire routing table
show ip route eigrp
show only EIGRP entries in the routing table
show ip eigrp neighbors
show all EIGRP neigbors
show ip eigrp topology
show entries in the EIGRP topology table
show ip protocols
shows routing protocols configuration
debug eigrp packet
shows hello packets sent/received between adjacent routers
debug ip eigrp events
shows EIGRP changes and updates as they occur on your network
lets take a look at the state of our 4 routers. RIP and EIGRP are running on each.
Notice how this command is giving different outputs between the two different IOS versions
IOS 15.1
Corp#
show ip protocols
Routing Protocol is "eigrp 10 "
Outgoing update filter list for all interfaces is not set
Incoming update filter list for all interfaces is not set
Default networks flagged in outgoing updates
Default networks accepted from incoming updates
Redistributing: eigrp 10
EIGRP-IPv4 Protocol for AS(10)
Metric weight K1=1, K2=0, K3=1, K4=0, K5=0
NSF-aware route hold timer is 240
Router-ID: 10.1.1.1
Topology : 0 (base)
Active Timer: 3 min
Distance: internal 90 external 170
Maximum path: 4
Maximum hopcount 100
Maximum metric variance 1
Automatic Summarization: disabled
Automatic address summarization:
Maximum path: 4
Routing for Networks:
10.0.0.0
Routing Information Sources:
Gateway Distance Last Update
10.1.5.2 90 0
10.1.3.2 90 6464
10.1.2.2 90 6795
10.1.4.2 90 7955
Distance: internal 90 external 170
Routing Protocol is "rip"
Sending updates every 30 seconds, next due in 10 seconds
Invalid after 180 seconds, hold down 180, flushed after 240
Outgoing update filter list for all interfaces is not set
Incoming update filter list for all interfaces is not set
Redistributing: rip
Default version control: send version 2, receive 2
Interface Send Recv Triggered RIP Key-chain
Vlan1 2 2
FastEthernet0/0 2 2
Serial0/1/0 2 2
Serial0/0/1 2 2
Serial0/0/0 2 2
Automatic network summarization is in effect
Maximum path: 4
Routing for Networks:
10.0.0.0
Passive Interface(s):
Routing Information Sources:
Gateway Distance Last Update
10.1.5.2 120 00:00:12
10.1.3.2 120 00:00:16
10.1.2.2 120 00:00:16
10.1.4.2 120 00:00:13
Distance: (default is 120)
IOS 12.4
R1#
show ip protocols
Routing Protocol is "eigrp 10 "
Outgoing update filter list for all interfaces is not set
Incoming update filter list for all interfaces is not set
Default networks flagged in outgoing updates
Default networks accepted from incoming updates
EIGRP metric weight K1=1, K2=0, K3=1, K4=0, K5=0
EIGRP maximum hopcount 100
EIGRP maximum metric variance 1
Redistributing: eigrp 10
Automatic network summarization is not in effect
Maximum path: 4
Routing for Networks:
10.0.0.0
192.168.10.0
192.168.20.0
Routing Information Sources:
Gateway Distance Last Update
10.1.3.1 90 6465
10.1.2.1 90 6794
Distance: internal 90 external 170
Routing Protocol is "rip"
Sending updates every 30 seconds, next due in 21 seconds
Invalid after 180 seconds, hold down 180, flushed after 240
Outgoing update filter list for all interfaces is not set
Incoming update filter list for all interfaces is not set
Redistributing: rip
Default version control: send version 2, receive 2
Interface Send Recv Triggered RIP Key-chain
FastEthernet0/0 2 2
FastEthernet0/1 2 2
Serial0/0/0 2 2
Serial0/0/1 2 2
Automatic network summarization is not in effect
Maximum path: 4
Routing for Networks:
10.0.0.0
192.168.10.0
192.168.20.0
Passive Interface(s):
Routing Information Sources:
Gateway Distance Last Update
10.1.3.1 120 00:00:06
10.1.2.1 120 00:00:06
Distance: (default is 120)
IOS 12.4
R2#
show ip protocols
Routing Protocol is "eigrp 10 "
Outgoing update filter list for all interfaces is not set
Incoming update filter list for all interfaces is not set
Default networks flagged in outgoing updates
Default networks accepted from incoming updates
EIGRP metric weight K1=1, K2=0, K3=1, K4=0, K5=0
EIGRP maximum hopcount 100
EIGRP maximum metric variance 1
Redistributing: eigrp 10
Automatic network summarization is not in effect
Maximum path: 4
Routing for Networks:
10.0.0.0
192.168.30.0
192.168.40.0
Routing Information Sources:
Gateway Distance Last Update
10.1.4.1 90 7955
Distance: internal 90 external 170
Routing Protocol is "rip"
Sending updates every 30 seconds, next due in 11 seconds
Invalid after 180 seconds, hold down 180, flushed after 240
Outgoing update filter list for all interfaces is not set
Incoming update filter list for all interfaces is not set
Redistributing: rip
Default version control: send version 2, receive 2
Interface Send Recv Triggered RIP Key-chain
FastEthernet0/0 2 2
FastEthernet0/1 2 2
Serial0/0/0 2 2
Automatic network summarization is in effect
Maximum path: 4
Routing for Networks:
10.0.0.0
192.168.30.0
192.168.40.0
Passive Interface(s):
Routing Information Sources:
Gateway Distance Last Update
10.1.4.1 120 00:00:20
Distance: (default is 120)
IOS 15.1
R3#
show ip protocols
Routing Protocol is "eigrp 10 "
Outgoing update filter list for all interfaces is not set
Incoming update filter list for all interfaces is not set
Default networks flagged in outgoing updates
Default networks accepted from incoming updates
Redistributing: eigrp 10
EIGRP-IPv4 Protocol for AS(10)
Metric weight K1=1, K2=0, K3=1, K4=0, K5=0
NSF-aware route hold timer is 240
Router-ID: 10.1.5.2
Topology : 0 (base)
Active Timer: 3 min
Distance: internal 90 external 170
Maximum path: 4
Maximum hopcount 100
Maximum metric variance 1
Automatic Summarization: disabled
Automatic address summarization:
Maximum path: 4
Routing for Networks:
10.0.0.0
172.16.0.0
Routing Information Sources:
Gateway Distance Last Update
10.1.5.1 90 0
Distance: internal 90 external 170
Routing Protocol is "rip"
Sending updates every 30 seconds, next due in 27 seconds
Invalid after 180 seconds, hold down 180, flushed after 240
Outgoing update filter list for all interfaces is not set
Incoming update filter list for all interfaces is not set
Redistributing: rip
Default version control: send version 2, receive 2
Interface Send Recv Triggered RIP Key-chain
Dot11Radio0/0/0 2 2
FastEthernet0/0 2 2
Automatic network summarization is not in effect
Maximum path: 4
Routing for Networks:
10.0.0.0
172.16.0.0
Passive Interface(s):
Routing Information Sources:
Gateway Distance Last Update
10.1.5.1 120 00:00:02
Distance: (default is 120)
I'm also noticing that we have inconsistent auto-summarization settings- I was having trouble with this earlier. The book discusses
getting rid of the 172.16.0.0 summarized route in the EIGRP settings. I was not able to get rid of it, I think because RIP is still on, and RIP forces auto-summary
Part of the challenge here is that the book is strictly dealing with IOS 12.4
I will now make sure to turn auto summary off for both RIP and EIGRP on each of the four routers.
OK the part I am forgetting is that we are running RIP V2 which does not force auto-summary but runs it optionally, and we must turn it off to avoid auto summarization.
Corp(config)#
router rip
Corp(config-router)#
no auto-summary
Corp(config-router)#
router eigrp 10
Corp(config-router)#
no auto-summary
R1(config)#
router rip
R1(config-router)#
no auto-summary
R1(config-router)#
router eigrp 10
R1(config-router)#
no auto-summary
R1(config)#
router rip
R1(config-router)#
no auto-summary
R1(config-router)#
router eigrp 10
R2(config-router)#
no auto-summary
R3(config)#
router rip
R3(config-router)#
no auto-summary
R3(config-router)#
router eigrp 10
R3(config-router)#
no auto-summary
and lets see how the output looks now. This time I'll do show ip protocols and
show ip route side by side for each router
IOS 15.1
Corp#
show ip protocols
Routing Protocol is "eigrp 10 "
Outgoing update filter list for all interfaces is not set
Incoming update filter list for all interfaces is not set
Default networks flagged in outgoing updates
Default networks accepted from incoming updates
Redistributing: eigrp 10
EIGRP-IPv4 Protocol for AS(10)
Metric weight K1=1, K2=0, K3=1, K4=0, K5=0
NSF-aware route hold timer is 240
Router-ID: 10.1.1.1
Topology : 0 (base)
Active Timer: 3 min
Distance: internal 90 external 170
Maximum path: 4
Maximum hopcount 100
Maximum metric variance 1
Automatic Summarization: disabled
Automatic address summarization:
Maximum path: 4
Routing for Networks:
10.0.0.0
Routing Information Sources:
Gateway Distance Last Update
10.1.5.2 90 0
10.1.3.2 90 6464
10.1.2.2 90 6795
10.1.4.2 90 7955
Distance: internal 90 external 170
Routing Protocol is "rip" doesnt necessarily mean RIPv1
Sending updates every 30 seconds, next due in 3 seconds
Invalid after 180 seconds, hold down 180, flushed after 240
Outgoing update filter list for all interfaces is not set
Incoming update filter list for all interfaces is not set
Redistributing: rip
Default version control: send version 2, receive 2 RIPv2 is specified
Interface Send Recv Triggered RIP Key-chain
Vlan1 2 2
FastEthernet0/0 2 2
Serial0/1/0 2 2
Serial0/0/1 2 2
Serial0/0/0 2 2
Automatic network summarization is not in effect
Maximum path: 4
Routing for Networks:
10.0.0.0
Passive Interface(s):
Routing Information Sources:
Gateway Distance Last Update
10.1.5.2 120 00:00:02
10.1.3.2 120 00:00:21
10.1.2.2 120 00:00:21
10.1.4.2 120 00:00:04
Distance: (default is 120)
IOS 15.1
Corp#
show ip route
Gateway of last resort is not set
10.0.0.0/8 is variably subnetted, 10 subnets, 2 masks
C 10.1.1.0/24 is directly connected, Vlan1
L 10.1.1.1/32 is directly connected, Vlan1
C 10.1.2.0/24 is directly connected, Serial0/0/0
L 10.1.2.1/32 is directly connected, Serial0/0/0
C 10.1.3.0/24 is directly connected, Serial0/0/1
L 10.1.3.1/32 is directly connected, Serial0/0/1
C 10.1.4.0/24 is directly connected, Serial0/1/0
L 10.1.4.1/32 is directly connected, Serial0/1/0
C 10.1.5.0/24 is directly connected, FastEthernet0/0
L 10.1.5.1/32 is directly connected, FastEthernet0/0
172.16.0.0/24 is subnetted, 1 subnets
D 172.16.10.0/24 [90/28160] via 10.1.5.2, 00:57:25, FastEthernet0/0
D 192.168.10.0/24 [90/2172416] via 10.1.3.2, 00:57:20, Serial0/0/1
[90/2172416] via 10.1.2.2, 00:57:20, Serial0/0/0
D 192.168.20.0/24 [90/2172416] via 10.1.3.2, 00:57:20, Serial0/0/1
[90/2172416] via 10.1.2.2, 00:57:20, Serial0/0/0
D 192.168.30.0/24 [90/2172416] via 10.1.4.2, 00:57:19, Serial0/1/0
D 192.168.40.0/24 [90/2172416] via 10.1.4.2, 00:57:19, Serial0/1/0
IOS 12.4
R1#
show ip protocols
Routing Protocol is "eigrp 10 "
Outgoing update filter list for all interfaces is not set
Incoming update filter list for all interfaces is not set
Default networks flagged in outgoing updates
Default networks accepted from incoming updates
EIGRP metric weight K1=1, K2=0, K3=1, K4=0, K5=0
EIGRP maximum hopcount 100
EIGRP maximum metric variance 1
Redistributing: eigrp 10
Automatic network summarization is not in effect
Maximum path: 4
Routing for Networks:
10.0.0.0
192.168.10.0
192.168.20.0
Routing Information Sources:
Gateway Distance Last Update
10.1.3.1 90 6465
10.1.2.1 90 6794
Distance: internal 90 external 170
Routing Protocol is "rip"
Sending updates every 30 seconds, next due in 26 seconds
Invalid after 180 seconds, hold down 180, flushed after 240
Outgoing update filter list for all interfaces is not set
Incoming update filter list for all interfaces is not set
Redistributing: rip
Default version control: send version 2, receive 2
Interface Send Recv Triggered RIP Key-chain
FastEthernet0/0 2 2
FastEthernet0/1 2 2
Serial0/0/0 2 2
Serial0/0/1 2 2
Automatic network summarization is not in effect
Maximum path: 4
Routing for Networks:
10.0.0.0
192.168.10.0
192.168.20.0
Passive Interface(s):
Routing Information Sources:
Gateway Distance Last Update
10.1.3.1 120 00:00:03
10.1.2.1 120 00:00:03
Distance: (default is 120)
IOS 12.4
R1#
show ip route
Gateway of last resort is not set
10.0.0.0/24 is subnetted, 5 subnets
D 10.1.1.0 [90/27769856] via 10.1.3.1, 00:54:47, Serial0/0/1
[90/27769856] via 10.1.2.1, 00:54:47, Serial0/0/0
C 10.1.2.0 is directly connected, Serial0/0/0
C 10.1.3.0 is directly connected, Serial0/0/1
D 10.1.4.0 [90/2681856] via 10.1.3.1, 00:54:47, Serial0/0/1
[90/2681856] via 10.1.2.1, 00:54:47, Serial0/0/0
D 10.1.5.0 [90/2172416] via 10.1.3.1, 00:54:47, Serial0/0/1
[90/2172416] via 10.1.2.1, 00:54:47, Serial0/0/0
172.16.0.0/24 is subnetted, 1 subnets
D 172.16.10.0 [90/2172416] via 10.1.3.1, 00:54:47, Serial0/0/1
[90/2172416] via 10.1.2.1, 00:54:47, Serial0/0/0
C 192.168.10.0/24 is directly connected, FastEthernet0/0
C 192.168.20.0/24 is directly connected, FastEthernet0/1
D 192.168.30.0/24 [90/2684416] via 10.1.3.1, 00:54:46, Serial0/0/1
[90/2684416] via 10.1.2.1, 00:54:46, Serial0/0/0
D 192.168.40.0/24 [90/2684416] via 10.1.3.1, 00:54:46, Serial0/0/1
[90/2684416] via 10.1.2.1, 00:54:46, Serial0/0/0
note that the DUAL routes being advertised from the 10.0.0.0 networks are all specific to the third octet.. that's because we are reading those routes
from their source, aka the router which they are directly connected to, Corp.
and on Corp, those networks were added to the interfaces with a /24 mask.
so even though our EIGRP config doesnt specifically include /24 networks.. we told it to include anything with a 10.x.x.x
Corp is advertising to R1 our /24 network interfaces that have a 10 in the first octet, EXCEPT the two which are directly connected to R1
10.1.1.0
10.1.4.0
10.1.5.0
are assumed to be the subnets based on the info we configured, which was 10.1.4.1/24 on corp, and 10.1.4.2/24 on r2 s0/0/0
nowhere in this configuration, have we entered the 10.1.4.0 network.
EIGRP is figuring it out based on the /24 mask we gave when assiging he IPs to the interfaces
IOS 12.4
R2#
show ip protocols
Routing Protocol is "eigrp 10 "
Outgoing update filter list for all interfaces is not set
Incoming update filter list for all interfaces is not set
Default networks flagged in outgoing updates
Default networks accepted from incoming updates
EIGRP metric weight K1=1, K2=0, K3=1, K4=0, K5=0
EIGRP maximum hopcount 100
EIGRP maximum metric variance 1
Redistributing: eigrp 10
Automatic network summarization is not in effect
Maximum path: 4
Routing for Networks:
10.0.0.0
192.168.30.0
192.168.40.0
Routing Information Sources:
Gateway Distance Last Update
10.1.4.1 90 7955
Distance: internal 90 external 170
Routing Protocol is "rip"
Sending updates every 30 seconds, next due in 18 seconds
Invalid after 180 seconds, hold down 180, flushed after 240
Outgoing update filter list for all interfaces is not set
Incoming update filter list for all interfaces is not set
Redistributing: rip
Default version control: send version 2, receive 2
Interface Send Recv Triggered RIP Key-chain
FastEthernet0/0 2 2
FastEthernet0/1 2 2
Serial0/0/0 2 2
Automatic network summarization is not in effect
Maximum path: 4
Routing for Networks:
10.0.0.0
192.168.30.0
192.168.40.0
Passive Interface(s):
Routing Information Sources:
Gateway Distance Last Update
10.1.4.1 120 00:00:07
Distance: (default is 120)
IOS 12.4
R2#
show ip route
Gateway of last resort is not set
10.0.0.0/24 is subnetted, 5 subnets
D 10.1.1.0 [90/27769856] via 10.1.4.1, 00:59:10, Serial0/0/0
D 10.1.2.0 [90/2681856] via 10.1.4.1, 00:59:10, Serial0/0/0
D 10.1.3.0 [90/2681856] via 10.1.4.1, 00:59:10, Serial0/0/0
C 10.1.4.0 is directly connected, Serial0/0/0
D 10.1.5.0 [90/2172416] via 10.1.4.1, 00:59:10, Serial0/0/0
172.16.0.0/24 is subnetted, 1 subnets
D 172.16.10.0 [90/2172416] via 10.1.4.1, 00:59:10, Serial0/0/0
D 192.168.10.0/24 [90/2684416] via 10.1.4.1, 00:59:10, Serial0/0/0
D 192.168.20.0/24 [90/2684416] via 10.1.4.1, 00:59:10, Serial0/0/0
C 192.168.30.0/24 is directly connected, FastEthernet0/0
C 192.168.40.0/24 is directly connected, FastEthernet0/1
IOS 15.1
R3#
show ip protocols
Routing Protocol is "eigrp 10 "
Outgoing update filter list for all interfaces is not set
Incoming update filter list for all interfaces is not set
Default networks flagged in outgoing updates
Default networks accepted from incoming updates
Redistributing: eigrp 10
EIGRP-IPv4 Protocol for AS(10)
Metric weight K1=1, K2=0, K3=1, K4=0, K5=0
NSF-aware route hold timer is 240
Router-ID: 10.1.5.2
Topology : 0 (base)
Active Timer: 3 min
Distance: internal 90 external 170
Maximum path: 4
Maximum hopcount 100
Maximum metric variance 1
Automatic Summarization: disabled
Automatic address summarization:
Maximum path: 4
Routing for Networks:
10.0.0.0
172.16.0.0
Routing Information Sources:
Gateway Distance Last Update
10.1.5.1 90 0
Distance: internal 90 external 170
Routing Protocol is "rip"
Sending updates every 30 seconds, next due in 15 seconds
Invalid after 180 seconds, hold down 180, flushed after 240
Outgoing update filter list for all interfaces is not set
Incoming update filter list for all interfaces is not set
Redistributing: rip
Default version control: send version 2, receive 2
Interface Send Recv Triggered RIP Key-chain
Dot11Radio0/0/0 2 2
FastEthernet0/0 2 2
Automatic network summarization is not in effect
Maximum path: 4
Routing for Networks:
10.0.0.0
172.16.0.0
Passive Interface(s):
Routing Information Sources:
Gateway Distance Last Update
10.1.5.1 120 00:00:14
Distance: (default is 120)
IOS 15.1
R3#
show ip route
Gateway of last resort is 10.1.5.1 to network 0.0.0.0
10.0.0.0/8 is variably subnetted, 6 subnets, 2 masks
D 10.1.1.0/24 [90/25628160] via 10.1.5.1, 00:59:52, FastEthernet0/0
D 10.1.2.0/24 [90/2172416] via 10.1.5.1, 00:59:47, FastEthernet0/0
D 10.1.3.0/24 [90/2172416] via 10.1.5.1, 00:59:52, FastEthernet0/0
D 10.1.4.0/24 [90/2172416] via 10.1.5.1, 00:59:52, FastEthernet0/0
C 10.1.5.0/24 is directly connected, FastEthernet0/0
L 10.1.5.2/32 is directly connected, FastEthernet0/0
172.16.0.0/16 is variably subnetted, 2 subnets, 2 masks
C 172.16.10.0/24 is directly connected, Dot11Radio0/0/0
L 172.16.10.1/32 is directly connected, Dot11Radio0/0/0
D 192.168.10.0/24 [90/2174976] via 10.1.5.1, 00:59:47, FastEthernet0/0
D 192.168.20.0/24 [90/2174976] via 10.1.5.1, 00:59:47, FastEthernet0/0
D 192.168.30.0/24 [90/2174976] via 10.1.5.1, 00:59:46, FastEthernet0/0
D 192.168.40.0/24 [90/2174976] via 10.1.5.1, 00:59:46, FastEthernet0/0
S* 0.0.0.0/0 [1/0] via 10.1.5.1
Observations:
Since this is a 15.1 router, we always get a "L" local route when
we have a "C" connected route. In R3's case, the 172.16.10.0 network
is directly connected. The interface which connects it, 172.16.10.1,
counts as a "local" route. This is NOT the case on the 12.4 routers.
looking to the left, our protocol output tells us two key facts for both EIGRP and RIP:
Routing for networks:
10.0.0.0
172.16.0.0
R3 is responsible for *sending* data about these two networks to our other EIGRP routers...
"I'm R3 and I can connect you to networks on the R3
router or networks on the Corp router"
Notice how the 192 networks arent listed. R3 isnt connected to a 192 network directly, nor is it connected to a neighbor who is directly connected.
If I, as a client, am sending data to a 192 network from the 172 network, I will start
at R3. Since R3 is receiving routes for the 192 networks via Corp, I will be able to reach a 192 network via Corp.
My connection to corp will happen VIA a "10.0.0.0" route.
R3 is technically only routing for 172 and 10 networks. Beyond that, it could potentially connect to many other different networks. But in terms of the R3 routing table,
all it can offer is a path out to the 172 network or the 10 network
Routing information sources:
10.1.5.1
In this case I can see that R3 is receiving routing data from one interface only,
and that is it's link to Corp. Some of the data we are receiving from Corp actually originates
at other routers, but we cant see that here; the data comes to us from Corp, and that is all we know
EIGRP TERMINOLOGY
FEASIBLE DISTANCE (FD)
the best metric among all paths, including to the next hop neighbor. You will only see the route with the lowest FD appear in the routing table
The FD is calculated by adding the reported distance from the neighbor (AD) plus the metric to that neighbor
ADVERTISED DISTANCE (AD)
the metric of a remote network as reported by a neighbor, listed second in parenthesis in toplogy table
P 192.168.20.0/24, 2 successors, FD is 2172416
via 10.1.3.2 (2172416/28160), Serial0/0/1
feasible / advertised
Neighbor Table
each router keeps state information about adjacent neighbors.. When a new neighbor is learned, the address and interface are recorded.
The neighbor table is stored in RAM.
Sequence numbres are used to match acks with update packets. The last squence number received from a neighbor is recorded so out of order packets
can be detected
Topology Table
acted upon by DUAL Diffusing Update Alogorithm. Contains all destinations advertised by neighboring routers.
For each neighbor, the adversited distance, which comes only from that neighbor's routing table, is recorded
The feasible distance is also recorded.
Feasible Successor
a PATH whose advertised distance is less than the feasible distance of the current succesor, and is considered a backup route.
EIGRP keeps up to 16 feasible successors in the toplogy table.
The one with the best metric (The Successor) is copied and placed into the routing table
Successor
the best route to a remote network, used by EIGRP to forward traffic. It's backed up by a feasible successor, if one is available.
lets demo some more of the commands
VERIFYING EIGRP
several commands available to verify and troubleshoot
show ip route
show the entire routing table
show ip route eigrp
show only EIGRP entries in the routing table
show ip eigrp neighbors
show all EIGRP neigbors
show ip eigrp topology
show entries in the EIGRP topology table
show ip protocols
shows routing protocols configuration
debug eigrp packet
shows hello packets sent/received between adjacent routers
debug ip eigrp events
shows EIGRP changes and updates as they occur on your network
Corp#
show ip eigrp ?
interfaces IP-EIGRP interfaces
neighbors IP-EIGRP neighbors
topology IP-EIGRP Topology Table
traffic IP-EIGRP Traffic Statistics
Corp#
show ip eigrp topology
IP-EIGRP Topology Table for AS 10/ID(10.1.5.1)
Codes: P - Passive, A - Active, U - Update, Q - Query, R - Reply,
r - Reply status
P 10.1.1.0/24, 1 successors, FD is 25625600
via Connected, Vlan1
P 10.1.2.0/24, 1 successors, FD is 2169856
via Connected, Serial0/0/0
P 10.1.3.0/24, 1 successors, FD is 2169856
via Connected, Serial0/0/1
P 10.1.4.0/24, 1 successors, FD is 2169856
via Connected, Serial0/1/0
P 10.1.5.0/24, 1 successors, FD is 28160
via Connected, FastEthernet0/0
P 172.16.10.0/24, 1 successors, FD is 28160
via 10.1.5.2 (28160/25600), FastEthernet0/0
P 192.168.10.0/24, 2 successors, FD is 2172416
via 10.1.3.2 (2172416/28160), Serial0/0/1
via 10.1.2.2 (2172416/28160), Serial0/0/0
P 192.168.20.0/24, 2 successors, FD is 2172416
via 10.1.3.2 (2172416/28160), Serial0/0/1
via 10.1.2.2 (2172416/28160), Serial0/0/0
P 192.168.30.0/24, 1 successors, FD is 2172416
via 10.1.4.2 (2172416/28160), Serial0/1/0
P 192.168.40.0/24, 1 successors, FD is 2172416
via 10.1.4.2 (2172416/28160), Serial0/1/0
the "P" preceding each entry is for PASSIVE
these routes are in a passive state, which is good
if they move to an ACTIVE state, it means the have lost their path in the network and looking for a replacement.
Each entry also shows the FEASIBLE DISTANCE, the next hop address, and the local egress interface
Corp#
show ip eigrp neighbors
IP-EIGRP neighbors for process 10
H Address Interface Hold Uptime SRTT RTO Q Seq
(sec) (ms) Cnt Num
0 10.1.5.2 Fa0/0 14 02:00:05 40 1000 0 19
1 10.1.3.2 Se0/0/1 13 01:59:59 40 1000 0 14
2 10.1.2.2 Se0/0/0 13 01:59:59 40 1000 0 13
3 10.1.4.2 Se0/1/0 12 01:59:57 40 1000 0 15
fields:
H - the order in which the neighbors were discovered
hold - how long the router will wait for a hello packet
uptime - how long the neigborship has been established
SRTT - smooth round trip timer - the time it takes for a round trip from this router, to neighbor, and back.
SRTT is used to determine how long to wait for a MULTICAST reply.
if a reply isnt received in time, the router switches to UNICASTS
RTO - Retransmission Time Out- is the time EIGRP waits before retransmitting a packet from the retransmission queue
Q - indicates wheter there are oustanding messages in the queue
Seq - indicates the sequence number of the last update from that neighbor. This is used to maintain syncrhonization and avoid duplicate
or out-of-sequence processing of messages
Corp#
show ip route eigrp
172.16.0.0/24 is subnetted, 1 subnets
D 172.16.10.0 [90/28160] via 10.1.5.2, 02:08:04, FastEthernet0/0
D 192.168.10.0/24 [90/2172416] via 10.1.3.2, 02:07:59, Serial0/0/1
[90/2172416] via 10.1.2.2, 02:07:59, Serial0/0/0
D 192.168.20.0/24 [90/2172416] via 10.1.3.2, 02:07:59, Serial0/0/1
[90/2172416] via 10.1.2.2, 02:07:59, Serial0/0/0
D 192.168.30.0/24 [90/2172416] via 10.1.4.2, 02:07:58, Serial0/1/0
D 192.168.40.0/24 [90/2172416] via 10.1.4.2, 02:07:58, Serial0/1/0
Corp#
show ip eigrp interfaces
IP-EIGRP interfaces for process 10
Xmit Queue Mean Pacing Time Multicast Pending
Interface Peers Un/Reliable SRTT Un/Reliable Flow Timer Routes
Vlan 0 0/0 1236 0/10 0 0
Fa0/0 1 0/0 1236 0/10 0 0
Se0/1/0 1 0/0 1236 0/10 0 0
Se0/0/1 1 0/0 1236 0/10 0 0
Se0/0/0 1 0/0 1236 0/10 0 0
Corp#
show ip protocols
Routing Protocol is "eigrp 10 "
Outgoing update filter list for all interfaces is not set
Incoming update filter list for all interfaces is not set
Default networks flagged in outgoing updates
Default networks accepted from incoming updates
Redistributing: eigrp 10
EIGRP-IPv4 Protocol for AS(10)
Metric weight K1=1, K2=0, K3=1, K4=0, K5=0 using K1 bandwidth and K2 delay by default
NSF-aware route hold timer is 240
Router-ID: 10.1.1.1
Topology : 0 (base)
Active Timer: 3 min
Distance: internal 90 external 170
Maximum path: 4
Maximum hopcount 100
Maximum metric variance 1
Automatic Summarization: disabled
Automatic address summarization:
Maximum path: 4
Routing for Networks:
10.0.0.0
Routing Information Sources:
Gateway Distance Last Update
10.1.5.2 90 0
10.1.3.2 90 8936
10.1.4.2 90 9511
10.1.2.2 90 9597
Distance: internal 90 external 170
Routing Protocol is "rip"
Sending updates every 30 seconds, next due in 13 seconds
Invalid after 180 seconds, hold down 180, flushed after 240
Outgoing update filter list for all interfaces is not set
Incoming update filter list for all interfaces is not set
Redistributing: rip
Default version control: send version 2, receive 2
Interface Send Recv Triggered RIP Key-chain
Vlan1 2 2
FastEthernet0/0 2 2
Serial0/0/1 2 2
Serial0/1/0 2 2
Serial0/0/0 2 2
Automatic network summarization is not in effect
Maximum path: 4
Routing for Networks:
10.0.0.0
Passive Interface(s):
Routing Information Sources:
Gateway Distance Last Update
10.1.5.2 120 00:00:05
10.1.3.2 120 00:00:12
10.1.2.2 120 00:00:12
10.1.4.2 120 00:00:17
Distance: (default is 120)
corp#
debug eigrp packet
break into two columns for readability
Observations:
There doesnt appear to be a pattern in the order each router is addressed, except that the TO's and FROM"s are grouped together
The TO messages dont show the destination IP, only the egress local interface
The FROM messages do show the remote IP, as well as the local ingress interface
Corp#
EIGRP: Received HELLO on FastEthernet0/0 nbr 10.1.5.2
AS 10, Flags 0x0, Seq 18/0 idbQ 0/0
hello from R3
Corp#
EIGRP: Received HELLO on Serial0/1/0 nbr 10.1.4.2
AS 10, Flags 0x0, Seq 16/0 idbQ 0/0
hello from R2
Corp#
EIGRP: Received HELLO on Serial0/0/0 nbr 10.1.2.2
AS 10, Flags 0x0, Seq 19/0 idbQ 0/0
hello from R1
------------------------------------------------------------
Corp#
EIGRP: Sending HELLO on Serial0/1/0
AS 10, Flags 0x0, Seq 21/0 idbQ 0/0 iidbQ un/rely 0/0
hello to R2
Corp#
EIGRP: Sending HELLO on FastEthernet0/0
AS 10, Flags 0x0, Seq 21/0 idbQ 0/0 iidbQ un/rely 0/0
hello to R3
Corp#
EIGRP: Sending HELLO on Serial0/0/1
AS 10, Flags 0x0, Seq 21/0 idbQ 0/0 iidbQ un/rely 0/0
hello to R1
Corp#
EIGRP: Sending HELLO on Serial0/0/0
AS 10, Flags 0x0, Seq 21/0 idbQ 0/0 iidbQ un/rely 0/0
hello to R1
Corp#
EIGRP: Sending HELLO on Vlan1
AS 10, Flags 0x0, Seq 21/0 idbQ 0/0 iidbQ un/rely 0/0
hello to switch card (not a router....)
------------------------------------------------------------
Corp#
EIGRP: Received HELLO on Serial0/0/1 nbr 10.1.3.2
AS 10, Flags 0x0, Seq 19/0 idbQ 0/0
hello from R1
Corp#
EIGRP: Received HELLO on FastEthernet0/0 nbr 10.1.5.2
AS 10, Flags 0x0, Seq 18/0 idbQ 0/0
hello from R3
Corp#
EIGRP: Received HELLO on Serial0/0/0 nbr 10.1.2.2
AS 10, Flags 0x0, Seq 19/0 idbQ 0/0
hello from R1
Corp#
EIGRP: Received HELLO on Serial0/1/0 nbr 10.1.4.2
AS 10, Flags 0x0, Seq 16/0 idbQ 0/0
hello from R2
------------------------------------------------------------
Corp#
EIGRP: Sending HELLO on Serial0/1/0
AS 10, Flags 0x0, Seq 21/0 idbQ 0/0 iidbQ un/rely 0/0
hello to R2... no neighbor IP?
Corp#
EIGRP: Sending HELLO on Serial0/0/0
AS 10, Flags 0x0, Seq 21/0 idbQ 0/0 iidbQ un/rely 0/0
hello to R1... no neighbor IP?
Corp#
EIGRP: Sending HELLO on FastEthernet0/0
AS 10, Flags 0x0, Seq 21/0 idbQ 0/0 iidbQ un/rely 0/0
hello to R3... no neighbor IP?
Corp#
EIGRP: Sending HELLO on Serial0/0/1
AS 10, Flags 0x0, Seq 21/0 idbQ 0/0 iidbQ un/rely 0/0
hello to R1
Corp#
EIGRP: Sending HELLO on Vlan1
AS 10, Flags 0x0, Seq 21/0 idbQ 0/0 iidbQ un/rely 0/0
hello to switch card (not a router)
------------------------------------------------------------
OUTPUT CONTINUES IN NEXT COLUMN
Corp#
EIGRP: Received HELLO on Serial0/0/1 nbr 10.1.3.2
AS 10, Flags 0x0, Seq 19/0 idbQ 0/0
hello from R1
Corp#
EIGRP: Received HELLO on FastEthernet0/0 nbr 10.1.5.2
AS 10, Flags 0x0, Seq 18/0 idbQ 0/0
hello from R3
Corp#
EIGRP: Received HELLO on Serial0/0/0 nbr 10.1.2.2
AS 10, Flags 0x0, Seq 19/0 idbQ 0/0
hello from R1
Corp#
EIGRP: Received HELLO on Serial0/1/0 nbr 10.1.4.2
AS 10, Flags 0x0, Seq 16/0 idbQ 0/0
hello from R2
------------------------------------------------------------
Corp#
EIGRP: Sending HELLO on Serial0/1/0
AS 10, Flags 0x0, Seq 21/0 idbQ 0/0 iidbQ un/rely 0/0
hello to R2
Corp#
EIGRP: Sending HELLO on Serial0/0/0
AS 10, Flags 0x0, Seq 21/0 idbQ 0/0 iidbQ un/rely 0/0
hello to R1
Corp#
EIGRP: Sending HELLO on Vlan1
AS 10, Flags 0x0, Seq 21/0 idbQ 0/0 iidbQ un/rely 0/0
hello to Corp switchcard
Corp#
EIGRP: Sending HELLO on Serial0/0/1
AS 10, Flags 0x0, Seq 21/0 idbQ 0/0 iidbQ un/rely 0/0
hello to R1
Corp#
EIGRP: Sending HELLO on FastEthernet0/0
AS 10, Flags 0x0, Seq 21/0 idbQ 0/0 iidbQ un/rely 0/0
hello to R3... no neighbor IP?
------------------------------------------------------------
Corp#
EIGRP: Received HELLO on Serial0/0/1 nbr 10.1.3.2
AS 10, Flags 0x0, Seq 19/0 idbQ 0/0
hello from R1
Corp#
EIGRP: Received HELLO on FastEthernet0/0 nbr 10.1.5.2
AS 10, Flags 0x0, Seq 18/0 idbQ 0/0
hello from R3
Corp#
EIGRP: Received HELLO on Serial0/1/0 nbr 10.1.4.2
AS 10, Flags 0x0, Seq 16/0 idbQ 0/0
hello from R2
Corp#
EIGRP: Received HELLO on Serial0/0/0 nbr 10.1.2.2
AS 10, Flags 0x0, Seq 19/0 idbQ 0/0
hello from R1
------------------------------------------------------------
Corp#
EIGRP: Sending HELLO on Serial0/1/0
AS 10, Flags 0x0, Seq 21/0 idbQ 0/0 iidbQ un/rely 0/0
hello to R2
Corp#
EIGRP: Sending HELLO on Vlan1
AS 10, Flags 0x0, Seq 21/0 idbQ 0/0 iidbQ un/rely 0/0
hello to Corp switchcard
EIGRP: Sending HELLO on Serial0/0/0
AS 10, Flags 0x0, Seq 21/0 idbQ 0/0 iidbQ un/rely 0/0
hello to R1
EIGRP: Sending HELLO on Serial0/0/1
AS 10, Flags 0x0, Seq 21/0 idbQ 0/0 iidbQ un/rely 0/0
hello to R1
Corp#
EIGRP: Sending HELLO on FastEthernet0/0
AS 10, Flags 0x0, Seq 21/0 idbQ 0/0 iidbQ un/rely 0/0
hello to R3
------------------------------------------------------------
Now some videos. To reinforce EIGRP concepts, and lead into OSPF
OSPF - OPEN SHORTEST PATH FIRST
Before enabling OSPF, we'll turn off RIP and EIGRP on all four routers.
Device(config)#
no router eigrp 10
Device(config)#
no router rip
The OSPF configs for the local egress ip address
Corp(config)#
router ospf 132
Corp(config)#
network 10.1.0.0 0.0.255.255 area 0
R1(config)#
router ospf 1
R1(config)#
network 10.1.0.0 0.0.255.255 area 0
R1(config)#
network 192.168.0.0 0.0.255.255 area 0
R2(config)#
router ospf 45678
R2(config)#
network 10.0.0.0 0.0.0.255 area 0
R2(config)#
network 192.168.30.1 0.0.0.0 area 0
R2(config)#
network 192.168.40.1 0.0.0.0 area 0
all 32 bits of the mask are specified for the 192 entries;
these are not network id's, they are HOST id's of the specific interfaces, which are EGRESS interfaces on the router we are configuring
R3(config)#
router ospf 1
R2(config)#
network 10.1.5.2 0.0.0.255 area 0
R2(config)#
network 172.16.10.0 0.0.0.255 area 0
Wildcard Masks
these notes are not intended to be a precise explanation of wlidcard masking, but rather a look into my thought process as I am learning the concept.
resources:
traceroute blog examples
routerjockey blog examples
subnetonline wildcard calculator
Ch 9 Exam Essentials
1. Know EIGRP features
classless (like RipV2 and OSPF)
distance vector
supports IP, IPX, appleTalk, IPV6
supports summaries and discontiguous networks
uses the Diffusing Update Algorithm (DUAL) to maintain route information
uses RTP to communicate with other EIGRP routers
uses the concept of an autonomous system to describe the set of contiguous routers that run the same routing protocol and share routing information
considered CLASSLESS- includes the subnet mask in its route updates
sends traditional distance-vector updates containing info about networks plus the cost of reaching them from the perspective of the advertising router
but not strictly distance-vector. Has link-state characteristics: synchronizes routing tables between neighbors at startup and then sends specific updates only when topology changes.
max hop count of 255 (default is 100)
but hop count is NOT a metric, like in RIP. Hop count is how many routers an EIGRP route update can traverse before being discarded. This limits the size of the AS.
2. Know how to configure EIGRP
the router eigrp [as] command turns EIGRP routing on in the router. Unlike RIPv1, EIGRP uses classless routing. BUT you can still configure as classful.
R1(config)#
router eigrp 10
enters router config mode
R1(config-router)#
network 10.0.0.0
on this router, interfaces that fall within 10.0.0.0 will advertise EIGRP info
3. Know how to verify EIGRP operation
Corp#
show ip
protocols
Corp#
show ip
route
Corp#
show ip
route eigrp
Corp#
show ip
eigrp neighbors
Corp#
show ip
eigrp topology
Corp#
show ip
eigrp interfaces
Corp#
show ip
protocols
info about all active routing protocols
Routing Protocol is "eigrp 10 "
Outgoing update filter list for all interfaces is not set
Incoming update filter list for all interfaces is not set
Default networks flagged in outgoing updates
Default networks accepted from incoming updates
Redistributing: eigrp 10
EIGRP-IPv4 Protocol for AS(10)
Metric weight K1=1, K2=0, K3=1, K4=0, K5=0
NSF-aware route hold timer is 240
Router-ID: 10.1.1.1
Topology : 0 (base)
Active Timer: 3 min
Distance: internal 90 external 170
Maximum path: 4
Maximum hopcount 100
Maximum metric variance 1
Automatic Summarization: disabled
Automatic address summarization:
Maximum path: 4
Routing for Networks:
10.0.0.0
Routing Information Sources:
Gateway Distance Last Update
10.1.2.2 90 200105
10.1.3.2 90 200113
10.1.4.2 90 254351
10.1.5.2 90 303742
Distance: internal 90 external 170
Corp#
show ip
protocols
(continued)
Routing Protocol is "rip"
Sending updates every 30 seconds, next due in 6 seconds
Invalid after 180 seconds, hold down 180, flushed after 240
Outgoing update filter list for all interfaces is not set
Incoming update filter list for all interfaces is not set
Redistributing: rip
Default version control: send version 2, receive 2
Interface Send Recv Triggered RIP Key-chain
Vlan1 2 2
FastEthernet0/0 2 2
Serial0/1/0 2 2
Serial0/0/1 2 2
Serial0/0/0 2 2
Automatic network summarization is not in effect
Maximum path: 4
Routing for Networks:
10.0.0.0
Passive Interface(s):
Routing Information Sources:
Gateway Distance Last Update
10.1.5.2 120 00:00:15
10.1.3.2 120 00:00:01
10.1.2.2 120 00:00:01
10.1.4.2 120 00:00:17
Distance: (default is 120)
Corp#
show ip
route
entire routing table
Codes: L - local, C - connected, S - static, R - RIP, M - mobile, B - BGP
D - EIGRP, EX - EIGRP external, O - OSPF, IA - OSPF inter area
N1 - OSPF NSSA external type 1, N2 - OSPF NSSA external type 2
E1 - OSPF external type 1, E2 - OSPF external type 2, E - EGP
i - IS-IS, L1 - IS-IS level-1, L2 - IS-IS level-2, ia - IS-IS inter area
* - candidate default, U - per-user static route, o - ODR
P - periodic downloaded static route
Gateway of last resort is not set
10.0.0.0/8 is variably subnetted, 10 subnets, 2 masks
C 10.1.1.0/24 is directly connected, Vlan1
L 10.1.1.1/32 is directly connected, Vlan1
C 10.1.2.0/24 is directly connected, Serial0/0/0
L 10.1.2.1/32 is directly connected, Serial0/0/0
C 10.1.3.0/24 is directly connected, Serial0/0/1
L 10.1.3.1/32 is directly connected, Serial0/0/1
C 10.1.4.0/24 is directly connected, Serial0/1/0
L 10.1.4.1/32 is directly connected, Serial0/1/0
C 10.1.5.0/24 is directly connected, FastEthernet0/0
L 10.1.5.1/32 is directly connected, FastEthernet0/0
172.16.0.0/16 is variably subnetted, 2 subnets, 2 masks
R 172.16.0.0/16 [120/1] via 10.1.5.2, 00:00:14, FastEthernet0/0
D 172.16.10.0/24 [90/28160] via 10.1.5.2, 00:07:23, FastEthernet0/0
D 192.168.10.0/24 [90/2172416] via 10.1.3.2, 00:09:13, Serial0/0/1
[90/2172416] via 10.1.2.2, 00:09:13, Serial0/0/0
D 192.168.20.0/24 [90/2172416] via 10.1.3.2, 00:09:13, Serial0/0/1
[90/2172416] via 10.1.2.2, 00:09:13, Serial0/0/0
D 192.168.30.0/24 [90/2172416] via 10.1.4.2, 00:08:59, Serial0/1/0
D 192.168.40.0/24 [90/2172416] via 10.1.4.2, 00:08:59, Serial0/1/0
Shows the entire routing table
Corp#
show ip
eigrp toplogy
all nets the Corp router can see, including on the other side of other routers
IP-EIGRP Topology Table for AS 10/ID(10.1.5.1)
Codes: P - Passive, A - Active, U - Update, Q - Query, R - Reply,
r - Reply status
directly connected via local egress interface
P 10.1.1.0/24, 1 successors, FD is 25625600
via Connected, Vlan1
P 10.1.2.0/24, 1 successors, FD is 2169856
via Connected, Serial0/0/0
P 10.1.3.0/24, 1 successors, FD is 2169856
via Connected, Serial0/0/1
P 10.1.4.0/24, 1 successors, FD is 2169856
via Connected, Serial0/1/0
P 10.1.5.0/24, 1 successors, FD is 28160
via Connected, FastEthernet0/0
remotely connected via remote ingress ip address
P 172.16.10.0/24, 1 successors, FD is 28160
via 10.1.5.2 (28160/25600), FastEthernet0/0
P 192.168.10.0/24, 2 successors, FD is 2172416
via 10.1.3.2 (2172416/28160), Serial0/0/1
via 10.1.2.2 (2172416/28160), Serial0/0/0
P 192.168.20.0/24, 2 successors, FD is 2172416
via 10.1.3.2 (2172416/28160), Serial0/0/1
via 10.1.2.2 (2172416/28160), Serial0/0/0
P 192.168.30.0/24, 1 successors, FD is 2172416
via 10.1.4.2 (2172416/28160), Serial0/1/0
P 192.168.40.0/24, 1 successors, FD is 2172416
via 10.1.4.2 (2172416/28160), Serial0/1/0
Corp#
show ip
eigrp interfaces
local interfaces on Corp, with peer data, 5 total, including VLAN1 (0 peers, no router on this network)
IP-EIGRP interfaces for process 10
Xmit Queue Mean Pacing Time Multicast Pending
Interface Peers Un/Reliable SRTT Un/Reliable Flow Timer Routes
Vlan 0 0/0 1236 0/10 0 0
Fa0/0 1 0/0 1236 0/10 0 0
Se0/0/1 1 0/0 1236 0/10 0 0
Se0/1/0 1 0/0 1236 0/10 0 0
Se0/0/0 1 0/0 1236 0/10 0 0
Corp#
show ip
eigrp neighbors
remote interfaces on the 4 neighboring routers
IP-EIGRP neighbors for process 10
H Address Interface Hold Uptime SRTT RTO Q Seq
(sec) (ms) Cnt Num
0 10.1.2.2 Se0/0/0 14 00:54:33 40 1000 0 58
1 10.1.3.2 Se0/0/1 10 00:54:33 40 1000 0 57
2 10.1.4.2 Se0/1/0 14 00:53:38 40 1000 0 51
3 10.1.5.2 Fa0/0 11 00:52:49 40 1000 0 33
4. Compare OSPF and RIPv1
RIPv1 is distance-vector and supports only classful routing. No VLSM
OSPF is link-state and supports VLSM and classless routing
5. Know how OSPF routers become neighboars and/or adjacent
they become neighbors when they see eachother's hello packets.
area id must match, links must be on the same subnet, hello/dead timers must be the same.
OSPF only shares routes with neigbors who have also established adjacencies. NOT ALL NEIGHBORS become adjacent.
When an OSPF router first receives a hello packet, it verifies that the data in some fields matches its own locally configured information.
Should any of the checked data be different, the hello packet is discarded and not processed. The data fields verified are the Area ID,
Authentication, Network Mask (on broadcast networks), Hello Interval, Router Dead Interval, and Options fields. If this information doesn’t match,
then neighborship is stuck in the down stage.
packetpushers.net
6. Be able to configure single-area OSPF
two commands:
router ospf [process id]
network x.x.x.x y.y.y.y area z
7. Be able to verify the operation of OSPF
Corp#
show ip
protocols
Corp#
show ip
route
Corp#
show ip
ospf
Corp#
show ip
ospf database
Corp#
show ip
ospf interface
Corp#
show ip
ospf neighbor
IOS 15.1
Corp#
show ip
protocols
Routing Protocol is "ospf 132"
Outgoing update filter list for all interfaces is not set
Incoming update filter list for all interfaces is not set
Router ID 10.1.5.1
Number of areas in this router is 1. 1 normal 0 stub 0 nssa
Maximum path: 4
Routing for Networks:
10.1.0.0 0.0.255.255 area 0
Routing Information Sources:
Gateway Distance Last Update
10.1.5.1 110 00:08:51
172.16.10.1 110 00:08:51
192.168.20.1 110 00:12:53
192.168.40.1 110 00:09:35
Distance: (default is 110)
IOS 15.1
Corp#
show ip
route
10.0.0.0/8 is variably subnetted, 10 subnets, 2 masks
C 10.1.1.0/24 is directly connected, Vlan1
L 10.1.1.1/32 is directly connected, Vlan1
C 10.1.2.0/24 is directly connected, Serial0/0/0
L 10.1.2.1/32 is directly connected, Serial0/0/0
C 10.1.3.0/24 is directly connected, Serial0/0/1
L 10.1.3.1/32 is directly connected, Serial0/0/1
C 10.1.4.0/24 is directly connected, Serial0/1/0
L 10.1.4.1/32 is directly connected, Serial0/1/0
C 10.1.5.0/24 is directly connected, FastEthernet0/0
L 10.1.5.1/32 is directly connected, FastEthernet0/0
172.16.0.0/24 is subnetted, 1 subnets
O 172.16.10.0/24 [110/10] via 10.1.5.2, 00:09:09, FastEthernet0/0
O 192.168.10.0/24 [110/65] via 10.1.2.2, 00:13:11, Serial0/0/0
O 192.168.20.0/24 [110/65] via 10.1.2.2, 00:13:01, Serial0/0/0
O 192.168.30.0/24 [110/65] via 10.1.4.2, 00:09:54, Serial0/1/0
O 192.168.40.0/24 [110/65] via 10.1.4.2, 00:09:54, Serial0/1/0
IOS 15.1
Corp#
show ip
ospf
Routing Process "ospf 132" with ID 10.1.5.1
Supports only single TOS(TOS0) routes
Supports opaque LSA
SPF schedule delay 5 secs, Hold time between two SPFs 10 secs
Minimum LSA interval 5 secs. Minimum LSA arrival 1 secs
Number of external LSA 0. Checksum Sum 0x000000
Number of opaque AS LSA 0. Checksum Sum 0x000000
Number of DCbitless external and opaque AS LSA 0
Number of DoNotAge external and opaque AS LSA 0
Number of areas in this router is 1. 1 normal 0 stub 0 nssa
External flood list length 0
Area BACKBONE(0)
Number of interfaces in this area is 5
Area has no authentication
SPF algorithm executed 7 times
Area ranges are
Number of LSA 5. Checksum Sum 0x034486
Number of opaque link LSA 0. Checksum Sum 0x000000
Number of DCbitless LSA 0
Number of indication LSA 0
Number of DoNotAge LSA 0
Flood list length 0
IOS 15.1
Corp#
show ip
ospf database
OSPF Router with ID (10.1.5.1) (Process ID 132)
Router Link States (Area 0)
Link ID ADV Router Age Seq# Checksum Link count
192.168.20.1 192.168.20.1 854 0x80000006 0x00ae08 6
192.168.40.1 192.168.40.1 656 0x80000004 0x006bc6 4
10.1.5.1 10.1.5.1 612 0x8000000f 0x00ab77 8
172.16.10.1 172.16.10.1 612 0x80000003 0x00b30d 2
Net Link States (Area 0)
Link ID ADV Router Age Seq# Checksum
10.1.5.1 10.1.5.1 612 0x80000001 0x00cc34
ADV Router aka RID/Router ID, the highest IP address on the router
we are seeing three connected routers + our own router (Corp at 10.1.5.1)
IOS 15.1
Corp#
show ip
ospf interface
Vlan1 is up, line protocol is up
Internet address is 10.1.1.1/24, Area 0
Process ID 132, Router ID 10.1.5.1, Network Type BROADCAST, Cost: 1
Transmit Delay is 1 sec, State DR, Priority 1
Designated Router (ID) 10.1.5.1, Interface address 10.1.1.1
No backup designated router on this network
Timer intervals configured, Hello 10, Dead 40, Wait 40, Retransmit 5
Hello due in 00:00:08
Index 1/1, flood queue length 0
Next 0x0(0)/0x0(0)
Last flood scan length is 1, maximum is 1
Last flood scan time is 0 msec, maximum is 0 msec
Neighbor Count is 0, Adjacent neighbor count is 0
Suppress hello for 0 neighbor(s)
FastEthernet0/0 is up, line protocol is up
Internet address is 10.1.5.1/24, Area 0
Process ID 132, Router ID 10.1.5.1, Network Type BROADCAST, Cost: 1
Transmit Delay is 1 sec, State DR, Priority 1
Designated Router (ID) 10.1.5.1, Interface address 10.1.5.1
Backup Designated Router (ID) 172.16.10.1, Interface address 10.1.5.2
Timer intervals configured, Hello 10, Dead 40, Wait 40, Retransmit 5
Hello due in 00:00:07
Index 2/2, flood queue length 0
Next 0x0(0)/0x0(0)
Last flood scan length is 1, maximum is 1
Last flood scan time is 0 msec, maximum is 0 msec
Neighbor Count is 1, Adjacent neighbor count is 1
Adjacent with neighbor 172.16.10.1 (Backup Designated Router)
Suppress hello for 0 neighbor(s)
Serial0/0/1 is up, line protocol is up
Internet address is 10.1.3.1/24, Area 0
Process ID 132, Router ID 10.1.5.1, Network Type POINT-TO-POINT, Cost: 64
Transmit Delay is 1 sec, State POINT-TO-POINT,
Timer intervals configured, Hello 10, Dead 40, Wait 40, Retransmit 5
Hello due in 00:00:07
Index 3/3, flood queue length 0
Next 0x0(0)/0x0(0)
Last flood scan length is 1, maximum is 1
Last flood scan time is 0 msec, maximum is 0 msec
Neighbor Count is 1 , Adjacent neighbor count is 1
Adjacent with neighbor 192.168.20.1
Suppress hello for 0 neighbor(s)
Serial0/1/0 is up, line protocol is up
Internet address is 10.1.4.1/24, Area 0
Process ID 132, Router ID 10.1.5.1, Network Type POINT-TO-POINT, Cost: 64
Transmit Delay is 1 sec, State POINT-TO-POINT,
Timer intervals configured, Hello 10, Dead 40, Wait 40, Retransmit 5
Hello due in 00:00:07
Index 4/4, flood queue length 0
Next 0x0(0)/0x0(0)
Last flood scan length is 1, maximum is 1
Last flood scan time is 0 msec, maximum is 0 msec
Neighbor Count is 1 , Adjacent neighbor count is 1
Adjacent with neighbor 192.168.40.1
Suppress hello for 0 neighbor(s)
Serial0/0/0 is up, line protocol is up
Internet address is 10.1.2.1/24, Area 0
Process ID 132, Router ID 10.1.5.1, Network Type POINT-TO-POINT, Cost: 64
Transmit Delay is 1 sec, State POINT-TO-POINT,
Timer intervals configured, Hello 10, Dead 40, Wait 40, Retransmit 5
Hello due in 00:00:07
Index 5/5, flood queue length 0
Next 0x0(0)/0x0(0)
Last flood scan length is 1, maximum is 1
Last flood scan time is 0 msec, maximum is 0 msec
Neighbor Count is 1 , Adjacent neighbor count is 1
Adjacent with neighbor 192.168.20.1
Suppress hello for 0 neighbor(s)
IOS 15.1
Corp#
show ip
ospf neighbor
Neighbor ID Pri State Dead Time Address Interface
192.168.20.1 0 FULL/ - 00:00:31 10.1.3.2 Serial0/0/1
192.168.40.1 0 FULL/ - 00:00:33 10.1.4.2 Serial0/1/0
192.168.20.1 0 FULL/ - 00:00:31 10.1.2.2 Serial0/0/0
172.16.10.1 1 FULL/BDR 00:00:32 10.1.5.2 FastEthernet0/0
Flashcards
Chapter 9 Written Lab 9.0
1. What four routed protocols are supported by EIGRP?
IPX, IPv4, IPv6, AppleTalk
2. When is redistribution required for EIGRP?
when there are multiple autonomous systems
redistribution is required when more than one EIGRP session or process is running and they are identified with different ASNs.
redistribution shares toplogy information between EIGRP sessions
3. What command would be used to enable EIGRP with an autonmous system number of 300?
router eigrp 300
4. What command will tell EIGRP that it is connected to network 172.10.0.0?
network 172.10.0.0
5. What type of EIGRP interface will neither send nor receive Hello packets?
passive-interface s0/0
6. Write the command that will enable OSPF process 101 on a router
router ospf 101
7. Write the command that will display details of all OSFP routing processes enabled on a router
show ip ospf
8. Write the command that will display interface-specific OSPF information
show ip ospf interface
9. Write the command that will display all OSPF neighbors
show ip ospf neighbor
10. Write the command that will display all different OSPF route types that are currently known by the router
show ip route ospf
Chapter 9 Hands-On Labs
Build the network and configure interfaces
LabA(config)#
int f0/0
LabA(config-if)#
ip addr 172.16.10.1 255.255.255.0
LabA(config-if)#
no shut
LabB(config)#
int f0/0
LabB(config-if)#
ip addr 172.16.10.2 255.255.255.0
LabB(config-if)#
no shut
LabB(config-if)#
int s0/0/0
LabB(config-if)#
ip addr 172.16.20.1 255.255.255.0
LabB(config-if)#
no shut
LabC(config)#
int f0/0
LabC(config-if)#
ip addr 172.16.30.1 255.255.255.0
LabC(config-if)#
no shut
LabC(config-if)#
int s0/0/0
LabC(config-if)#
ip addr 172.16.20.2 255.255.255.0
LabC(config-if)#
no shut
LabC(config-if)#
int s0/0/1
LabC(config-if)#
ip addr 172.16.40.1 255.255.255.0
LabC(config-if)#
no shut
LabD(config)#
int s0/0/0
LabD(config-if)#
ip addr 172.16.40.2 255.255.255.0
LabD(config-if)#
no shut
LabD(config-if)#
int f0/0
LabD(config-if)#
ip addr 172.16.50.1 255.255.255.0
LabD(config-if)#
no shut
9.1 - Configure and Verfiy EIGRP
configure EIGRP on all 4 routers and observe results
LabA
LabA(config)#
router eigrp 100
LabA(config-router)#
net 172.16.0.0
[no output]
LabA#
show ip eigrp neighbors
IP-EIGRP neighbors for process 100
LabA#
show ip eigrp topology
IP-EIGRP Topology Table for AS 100/ID(172.16.10.1)
Codes: P - Passive, A - Active, U - Update, Q - Query, R - Reply,
r - Reply status
P 172.16.10.0/24, 1 successors, FD is 28160
via Connected, FastEthernet0/0
LabA#
show ip eigrp interfaces
IP-EIGRP interfaces for process 100
Xmit Queue Mean Pacing Time Multicast Pending
Interface Peers Un/Reliable SRTT Un/Reliable Flow Timer Routes
Fa0/0 0 0/0 1236 0/10 0 0
no neighbors at this point since EIGRP is only active on this router. One successor AKA route, which is the connection out of this router.
But note that we have no information about what's on the other side of that link
LabB
LabB(config)#
router eigrp 100
LabB(config-router)#
net 172.16.0.0
%DUAL-5-NBRCHANGE: IP-EIGRP 100:
Neighbor 172.16.10.1 (FastEthernet0/0) is up: new adjacency
LabB#
show ip eigrp neighbors
IP-EIGRP neighbors for process 100
H Address Interface Hold Uptime SRTT RTO Q Seq
(sec) (ms) Cnt Num
0 172.16.10.1 Fa0/0 12 00:00:14 40 1000 0 1
LabB#
show ip eigrp topology
IP-EIGRP Topology Table for AS 100/ID(172.16.20.1)
Codes: P - Passive, A - Active, U - Update, Q - Query, R - Reply,
r - Reply status
P 172.16.10.0/24, 1 successors, FD is 28160
via Connected, FastEthernet0/0
P 172.16.20.0/24, 1 successors, FD is 2169856
via Connected, Serial0/0/0
LabB#
show ip eigrp interfaces
IP-EIGRP interfaces for process 100
Xmit Queue Mean Pacing Time Multicast Pending
Interface Peers Un/Reliable SRTT Un/Reliable Flow Timer Routes
Fa0/0 1 0/0 1236 0/10 0 0
Se0/0/0 0 0/0 1236 0/10 0 0
We can see a neighbor at .1
We now have two paths out of this router. Left to neighbor. Exit at right is available as successor(route), but again we have no info about
what is on the other side, since that router has no EIGRP yet (s0/0/0 has no peers, but is an EIGRP interface)
LabC
LabC(config)#
router eigrp 100
LabC(config-router)#
net 172.16.0.0
%DUAL-5-NBRCHANGE: IP-EIGRP 100:
Neighbor 172.16.20.1 (Serial0/0/0) is up: new adjacency
LabC#
show ip eigrp neighbors
IP-EIGRP neighbors for process 100
H Address Interface Hold Uptime SRTT RTO Q Seq
(sec) (ms) Cnt Num
0 172.16.20.1 Se0/0/0 12 00:00:25 40 1000 0 8
LabC#
show ip eigrp toplogy
IP-EIGRP Topology Table for AS 100/ID(172.16.40.1)
Codes: P - Passive, A - Active, U - Update, Q - Query, R - Reply,
r - Reply status
P 172.16.10.0/24, 1 successors, FD is 2172416
via 172.16.20.1 (2172416/28160), Serial0/0/0
P 172.16.20.0/24, 1 successors, FD is 2169856
via Connected, Serial0/0/0
P 172.16.30.0/24, 1 successors, FD is 28160
via Connected, FastEthernet0/0
P 172.16.40.0/24, 1 successors, FD is 2169856
via Connected, Serial0/0/1
LabC#
show ip eigrp interfaces
IP-EIGRP interfaces for process 100
Xmit Queue Mean Pacing Time Multicast Pending
Interface Peers Un/Reliable SRTT Un/Reliable Flow Timer Routes
Fa0/0 0 0/0 1236 0/10 0 0
Se0/0/0 1 0/0 1236 0/10 0 0
Se0/0/1 0 0/0 1236 0/10 0 0
.1 router B interface is now a neighbor.
LabC topology shows the 3 direct connected networks AND the network on the other side of LabB since LabB is our EIGRP neighbor
3 eigrp interfaces:
Fa0/0 is ours at LabC- no peers bc there is no eigrp router on the other end
s0/0/0 is our interface out left to LabB which is an EIGRP peer
s0/0/1 is our interface out right which does not see an EIGRP peer but does put that net 172.16.40.0 in our topology
LabD
LabD(config)#
router eigrp 100
LabD(config-router)#
net 172.16.0.0
%DUAL-5-NBRCHANGE: IP-EIGRP 100:
Neighbor 172.16.40.1 (Serial0/0/0) is up: new adjacency
LabD#
show ip eigrp neighbors
IP-EIGRP neighbors for process 100
H Address Interface Hold Uptime SRTT RTO Q Seq
(sec) (ms) Cnt Num
0 172.16.40.1 Se0/0/0 11 00:00:14 40 1000 0 6
LabD#
show ip eigrp topology
IP-EIGRP Topology Table for AS 100/ID(172.16.50.1)
Codes: P - Passive, A - Active, U - Update, Q - Query, R - Reply,
r - Reply status
P 172.16.10.0/24, 1 successors, FD is 2684416
via 172.16.40.1 (2684416/2172416), Serial0/0/0
P 172.16.20.0/24, 1 successors, FD is 2681856
via 172.16.40.1 (2681856/2169856), Serial0/0/0
P 172.16.30.0/24, 1 successors, FD is 2172416
via 172.16.40.1 (2172416/28160), Serial0/0/0
P 172.16.40.0/24, 1 successors, FD is 2169856
via Connected, Serial0/0/0
P 172.16.50.0/24, 1 successors, FD is 28160
via Connected, FastEthernet0/0
LabD#
show ip eigrp interfaces
IP-EIGRP interfaces for process 100
Xmit Queue Mean Pacing Time Multicast Pending
Interface Peers Un/Reliable SRTT Un/Reliable Flow Timer Routes
Fa0/0 0 0/0 1236 0/10 0 0
Se0/0/0 1 0/0 1236 0/10 0 0
LabC to our left is now a neighbor at 172.16.40.1
toplogy shows a route out to the right (no router on that end)
a route to the left to LabC .40.0
the .10.0, .20.0, and .30.0 networks via info from LabC
2 eigrp interfaces-
fa0/0 out to the right
s0/0/0 out left to LabC
Time to remove EIGRP from all four routers to prepare for the OSPF lab next,
since EIGRP has a lower AD than OSPF
LabA(config)#
no router eigrp 100
LabB(config)#
no router eigrp 100
LabC(config)#
no router eigrp 100
LabD(config)#
no router eigrp 100
9.2 - Enabling the OSPF Process
9.3 - Configuring OSPF Interfaces
9.4 - Verifying OSPF Operation
LabA
LabA(config)#
router ospf 100
LabA(config-router)#
net 172.16.10.1 0.0.0.0 area 0
[no output]
LabA#
show ip ospf neighbor
[no output]
LabA#
show ip ospf database
OSPF Router with ID (172.16.10.1) (Process ID 100)
Router Link States (Area 0)
Link ID ADV Router Age Seq# Checksum Link count
172.16.10.1 172.16.10.1 44 0x80000001 0x00b24b 1
LabA#
show ip ospf interface
FastEthernet0/0 is up, line protocol is up
Internet address is 172.16.10.1/24, Area 0
Process ID 100, Router ID 172.16.10.1, Network Type BROADCAST, Cost: 1
Transmit Delay is 1 sec, State DR, Priority 1
Designated Router (ID) 172.16.10.1, Interface address 172.16.10.1
No backup designated router on this network
Timer intervals configured, Hello 10, Dead 40, Wait 40, Retransmit 5
Hello due in 00:00:08
Index 1/1, flood queue length 0
Next 0x0(0)/0x0(0)
Last flood scan length is 1, maximum is 1
Last flood scan time is 0 msec, maximum is 0 msec
Neighbor Count is 0, Adjacent neighbor count is 0
Suppress hello for 0 neighbor(s)
we're including this router's interface 172.16.10.1 in our ospf area 0
fa0/0 now registers as an ospf interface
the ospf database includes data about this link only.... LabA is counting itself(10.1) as ADVERTISTING router?
the designated router is .1 LabA
LabB
LabB(config)#
router ospf 101
LabB(config-router)#
net 172.16.10.2 0.0.0.0 area 0
LabB(config-router)#
net 172.16.20.1 0.0.0.0 area 0
01:26:36: %OSPF-5-ADJCHG: Process 101, Nbr 172.16.10.1
on FastEthernet0/0 from LOADING to FULL, Loading Done
LabB#
show ip ospf neighbor
Neighbor ID Pri State Dead Time Address Interface
172.16.10.1 1 FULL/DR 00:00:33 172.16.10.1
LabB#
show ip ospf database
OSPF Router with ID (172.16.20.1) (Process ID 101)
Router Link States (Area 0)
Link ID ADV Router Age Seq# Checksum Link count
172.16.10.1 172.16.10.1 145 0x80000002 0x0067cd 1
172.16.20.1 172.16.20.1 32 0x80000003 0x006e8f 2
Net Link States (Area 0)
Link ID ADV Router Age Seq# Checksum
172.16.10.1 172.16.10.1 145 0x80000001 0x00953d
LabB#
show ip ospf interface
FastEthernet0/0 is up, line protocol is up
Internet address is 172.16.10.2/24, Area 0
Process ID 101, Router ID 172.16.20.1, Network Type BROADCAST, Cost: 1
Transmit Delay is 1 sec, State BDR, Priority 1
Designated Router (ID) 172.16.10.1, Interface address 172.16.10.1
Backup Designated Router (ID) 172.16.20.1, Interface address 172.16.10.2
Timer intervals configured, Hello 10, Dead 40, Wait 40, Retransmit 5
Hello due in 00:00:03
Index 1/1, flood queue length 0
Next 0x0(0)/0x0(0)
Last flood scan length is 1, maximum is 1
Last flood scan time is 0 msec, maximum is 0 msec
Neighbor Count is 1, Adjacent neighbor count is 1
Adjacent with neighbor 172.16.10.1 (Designated Router)
Suppress hello for 0 neighbor(s)
Serial0/0/0 is up, line protocol is up
Internet address is 172.16.20.1/24, Area 0
Process ID 101, Router ID 172.16.20.1, Network Type POINT-TO-POINT, Cost: 64
Transmit Delay is 1 sec, State POINT-TO-POINT,
Timer intervals configured, Hello 10, Dead 40, Wait 40, Retransmit 5
Hello due in 00:00:04
Index 2/2, flood queue length 0
Next 0x0(0)/0x0(0)
Last flood scan length is 1, maximum is 1
Last flood scan time is 0 msec, maximum is 0 msec
Suppress hello for 0 neighbor(s)
We've include the two interfaces on this router in the OSPF area
and can now see Router A's interface 10.1 to the left as a neighbor in the area
the "OSPF Database" now shows two links 20.1(local) and 10.1(neighbor) as 'router link states'.
"ADV Router" means advertising router for the two links. The link address is used as the advertising router.
database shows "Net Link States" category with one entry- 172.16.10.1 which is the address of neighbor router to our left
we have two local OSPF interfaces- f0/0 and s0/0/0
LabC
LabC(config)#
router ospf 102
LabC(config-router)#
net 172.16.20.2 0.0.0.0 area 0
LabC(config-router)#
net 172.16.30.1 0.0.0.0 area 0
LabC(config-router)#
net 172.16.40.1 0.0.0.0 area 0
01:33:54: %OSPF-5-ADJCHG: Process 102, Nbr 172.16.20.1
on Serial0/0/0 from LOADING to FULL, Loading Done
LabC#
show ip ospf neighbor
Neighbor ID Pri State Dead Time Address Interface
172.16.20.1 0 FULL/ - 00:00:30 172.16.20.1 Serial0/0/0
LabC#
show ip ospf database
OSPF Router with ID (172.16.40.1) (Process ID 102)
Router Link States (Area 0)
Link ID ADV Router Age Seq# Checksum Link count
172.16.10.1 172.16.10.1 542 0x80000002 0x0067cd 1
172.16.20.1 172.16.20.1 90 0x80000004 0x00a551 3
172.16.40.1 172.16.40.1 37 0x80000004 0x00e47c 4
Net Link States (Area 0)
Link ID ADV Router Age Seq# Checksum
172.16.10.1 172.16.10.1 542 0x80000001 0x00953d
LabC#
show ip ospf interface
Serial0/0/0 is up, line protocol is up
Internet address is 172.16.20.2/24, Area 0
Process ID 102, Router ID 172.16.40.1, Network Type POINT-TO-POINT, Cost: 64
Transmit Delay is 1 sec, State POINT-TO-POINT,
Timer intervals configured, Hello 10, Dead 40, Wait 40, Retransmit 5
Hello due in 00:00:01
Index 1/1, flood queue length 0
Next 0x0(0)/0x0(0)
Last flood scan length is 1, maximum is 1
Last flood scan time is 0 msec, maximum is 0 msec
Neighbor Count is 1 , Adjacent neighbor count is 1
Adjacent with neighbor 172.16.20.1
Suppress hello for 0 neighbor(s)
FastEthernet0/0 is up, line protocol is up
Internet address is 172.16.30.1/24, Area 0
Process ID 102, Router ID 172.16.40.1, Network Type BROADCAST, Cost: 1
Transmit Delay is 1 sec, State DR, Priority 1
Designated Router (ID) 172.16.40.1, Interface address 172.16.30.1
No backup designated router on this network
Timer intervals configured, Hello 10, Dead 40, Wait 40, Retransmit 5
Hello due in 00:00:02
Index 2/2, flood queue length 0
Next 0x0(0)/0x0(0)
Last flood scan length is 1, maximum is 1
Last flood scan time is 0 msec, maximum is 0 msec
Neighbor Count is 0, Adjacent neighbor count is 0
Suppress hello for 0 neighbor(s)
Serial0/0/1 is up, line protocol is up
Internet address is 172.16.40.1/24, Area 0
Process ID 102, Router ID 172.16.40.1, Network Type POINT-TO-POINT, Cost: 64
Transmit Delay is 1 sec, State POINT-TO-POINT,
Timer intervals configured, Hello 10, Dead 40, Wait 40, Retransmit 5
Hello due in 00:00:08
Index 3/3, flood queue length 0
Next 0x0(0)/0x0(0)
Last flood scan length is 1, maximum is 1
Last flood scan time is 0 msec, maximum is 0 msec
Suppress hello for 0 neighbor(s)
we include the three nets conneted to labC in the area.. 20.0, 30.0, and 40.0
link to our left, 20.1 is visible as "Neighbor"
OSPF Database-
Router Link States are
10.1(Router A)
20.1(Router B)
40.1(Router C)(This router)
Net Link States
10.1(Router A)... why does only Router A show here?
Reference- router link state vs net link state
Router Link States are type 1 LSAs. It lists all the routers in the area and the number of interfaces. 40.1 has 4 interfaces
Net Link States are the multi-access networks (Type 2 LSAs). The ADV (advertising router) is the DR.
LabD
LabD(config)#
router ospf 103
LabD(config-router)#
net 172.16.40.2 0.0.0.0 area 0
LabD(config-router)#
net 172.16.50.1 0.0.0.0 area 0
01:37:11: %OSPF-5-ADJCHG: Process 103, Nbr 172.16.40.1
on Serial0/0/0 from LOADING to FULL, Loading Done
LabD#
show ip ospf neighbor
Neighbor ID Pri State Dead Time Address Interface
172.16.40.1 0 FULL/ - 00:00:32 172.16.40.1 Serial0/0/0
LabD#
show ip ospf database
OSPF Router with ID (172.16.50.1) (Process ID 103)
Router Link States (Area 0)
Link ID ADV Router Age Seq# Checksum Link count
172.16.10.1 172.16.10.1 785 0x80000002 0x0067cd 1
172.16.20.1 172.16.20.1 333 0x80000004 0x00a551 3
172.16.40.1 172.16.40.1 111 0x80000005 0x00013b 5
172.16.50.1 172.16.50.1 53 0x80000003 0x001023 3
Net Link States (Area 0)
Link ID ADV Router Age Seq# Checksum
172.16.10.1 172.16.10.1 785 0x80000001 0x00953d
LabD#
show ip ospf interface
Serial0/0/0 is up, line protocol is up
Internet address is 172.16.40.2/24, Area 0
Process ID 103, Router ID 172.16.50.1, Network Type POINT-TO-POINT, Cost: 64
Transmit Delay is 1 sec, State POINT-TO-POINT,
Timer intervals configured, Hello 10, Dead 40, Wait 40, Retransmit 5
Hello due in 00:00:01
Index 1/1, flood queue length 0
Next 0x0(0)/0x0(0)
Last flood scan length is 1, maximum is 1
Last flood scan time is 0 msec, maximum is 0 msec
Neighbor Count is 1 , Adjacent neighbor count is 1
Adjacent with neighbor 172.16.40.1
Suppress hello for 0 neighbor(s)
FastEthernet0/0 is up, line protocol is up
Internet address is 172.16.50.1/24, Area 0
Process ID 103, Router ID 172.16.50.1, Network Type BROADCAST, Cost: 1
Transmit Delay is 1 sec, State WAITING, Priority 1
No designated router on this network
No backup designated router on this network
Timer intervals configured, Hello 10, Dead 40, Wait 40, Retransmit 5
Hello due in 00:00:04
Index 2/2, flood queue length 0
Next 0x0(0)/0x0(0)
Last flood scan length is 1, maximum is 1
Last flood scan time is 0 msec, maximum is 0 msec
Neighbor Count is 0, Adjacent neighbor count is 0
Suppress hello for 0 neighbor(s)
observations
the OSPF databases now match across all 4 routers.
NOTE that this is a database of routers, identified by
router ID. It is not a topology that lists routers AND routes,
like in the "equivalent" eigrp command.show eigrp topology
----------------------------------------------------------------------------------
PAUSE- a tale of a misconfigured network
After a 9 month hiatus, I am reviewing this book and have made it back to Chapter 9. I'm studing this webpage, working thorough the OSPF configurations
described above, and I get stuck on the concept of "link count" under "Router Link States" found in the output of show ip ospf database
The structure of the notes above is helpful, because I was tracking the state of each router BEFORE i made changes to the subsquent router. But just to be sure,
today I decided to recreate the topology, then configure each router one at a time, noting the results as I went.
And I ran into some problems.
Here is the original topology:
And today's recreated toplogy:
After replicating the toplogy and programming the IP addresses on each router, I started on configurations, just like before:
LabA
LabA(config)#
router ospf 100
LabA(config-router)#
net 172.16.10.1 0.0.0.0 area 0
[no output]
LabA#
show ip ospf neighbor
[no output]
LabA#
show ip ospf database
OSPF Router with ID (172.16.10.1) (Process ID 100)
Router Link States (Area 0)
Link ID ADV Router Age Seq# Checksum Link count
172.16.10.1 172.16.10.1 44 0x80000001 0x00b24b 1
LabA#
show ip ospf interface
FastEthernet0/0 is up, line protocol is up
Internet address is 172.16.10.1/24, Area 0
Process ID 100, Router ID 172.16.10.1, Network Type BROADCAST, Cost: 1
Transmit Delay is 1 sec, State DR, Priority 1
Designated Router (ID) 172.16.10.1, Interface address 172.16.10.1
No backup designated router on this network
Timer intervals configured, Hello 10, Dead 40, Wait 40, Retransmit 5
Hello due in 00:00:08
Index 1/1, flood queue length 0
Next 0x0(0)/0x0(0)
Last flood scan length is 1, maximum is 1
Last flood scan time is 0 msec, maximum is 0 msec
Neighbor Count is 0, Adjacent neighbor count is 0
Suppress hello for 0 neighbor(s)
good so far.... On to LabB router
LabB
LabB(config)#
router ospf 101
LabB(config-router)#
net 172.16.10.2 0.0.0.0 area 0
LabB(config-router)#
net 172.16.20.1 0.0.0.0 area 0
01:26:36: %OSPF-5-ADJCHG: Process 101, Nbr 172.16.10.1
on FastEthernet0/0 from LOADING to FULL, Loading Done
LabB#
show ip ospf neighbor
Neighbor ID Pri State Dead Time Address Interface
172.16.10.1 1 FULL/DR 00:00:33 172.16.10.1
LabB#
show ip ospf database
OSPF Router with ID (172.16.20.1) (Process ID 101)
Router Link States (Area 0)
Link ID ADV Router Age Seq# Checksum Link count
172.16.10.1 172.16.10.1 145 0x80000002 0x0067cd 1
172.16.20.1 172.16.20.1 32 0x80000003 0x006e8f 2
Net Link States (Area 0)
Link ID ADV Router Age Seq# Checksum
172.16.10.1 172.16.10.1 145 0x80000001 0x00953d
LabB#
show ip ospf interface
FastEthernet0/0 is up, line protocol is up
Internet address is 172.16.10.2/24, Area 0
Process ID 101, Router ID 172.16.20.1, Network Type BROADCAST, Cost: 1
Transmit Delay is 1 sec, State BDR, Priority 1
Designated Router (ID) 172.16.10.1, Interface address 172.16.10.1
Backup Designated Router (ID) 172.16.20.1, Interface address 172.16.10.2
Timer intervals configured, Hello 10, Dead 40, Wait 40, Retransmit 5
Hello due in 00:00:03
Index 1/1, flood queue length 0
Next 0x0(0)/0x0(0)
Last flood scan length is 1, maximum is 1
Last flood scan time is 0 msec, maximum is 0 msec
Neighbor Count is 1, Adjacent neighbor count is 1
Adjacent with neighbor 172.16.10.1 (Designated Router)
Suppress hello for 0 neighbor(s)
Serial0/0/0 is up, line protocol is up
Internet address is 172.16.20.1/24, Area 0
Process ID 101, Router ID 172.16.20.1, Network Type POINT-TO-POINT, Cost: 64
Transmit Delay is 1 sec, State POINT-TO-POINT,
Timer intervals configured, Hello 10, Dead 40, Wait 40, Retransmit 5
Hello due in 00:00:04
Index 2/2, flood queue length 0
Next 0x0(0)/0x0(0)
Last flood scan length is 1, maximum is 1
Last flood scan time is 0 msec, maximum is 0 msec
Suppress hello for 0 neighbor(s)
still looks good; same as before.... On to LabC router
LabC
LabC(config)#
router ospf 102
LabC(config-router)#
net 172.16.20.2 0.0.0.0 area 0
LabC(config-router)#
net 172.16.30.1 0.0.0.0 area 0
LabC(config-router)#
net 172.16.40.1 0.0.0.0 area 0
01:33:54: %OSPF-5-ADJCHG: Process 102, Nbr 172.16.20.1
on Serial0/0/0 from LOADING to FULL, Loading Done
LabC#
show ip ospf neighbor
[no output]
And here is where I ran into trouble. The show ip ospf neighbor command returns nothing. How can
that be?
After awhile I realized it is due to a misconfiguration in the topology.
For Lab C, I programmed the interfaces as follows:
LabC(config)#
int f0/0
LabC(config-if)#
ip addr 172.16.30.1 255.255.255.0
LabC(config-if)#
no shut
LabC(config-if)#
int s0/0/0
LabC(config-if)#
ip addr 172.16.20.2 255.255.255.0
LabC(config-if)#
no shut
LabC(config-if)#
int s0/0/1
LabC(config-if)#
ip addr 172.16.40.1 255.255.255.0
LabC(config-if)#
no shut
and again here is the topology for that router:
but here is what it SHOULD HAVE looked like (as it did the first time I built it)
S0/0/0 and S0/0/1 are swapped. When I gave the IP 172.16.20.2 to s/0/0/0, thinking that was the interface on the left side
which faces Lab B, I was actually giving 172.16.20.2 to the right side, facing LabC (which has no OSPF configs yet.)
Since the left side got got the IP intended for the right side which was 172.16.40.1
the inverse also occured-
the right side got the IP intended for the left which was 172.16.20.2
LabC left side should have been
s0/0/0 with 20.2
and LabC right side should have been
s0/0/1 with 40.1
The correct IPs were mapped to the correct interfaces. But the mistake happened before I even programmed them.
When I made the connections from LabB to LabC and from LabD to LabC, I plugged then into the wrong ports.
Interestingly.. not only is this causing OSPF to not see B as a neighbor from C.. but B and C cannot ping eachother either.
@B the config is 172.16.20.1/24 @ S0/0/0
@C the config is 172.16.40.1/24 @ S/0/0/1
meaning they are not even on the same network! But the system is not throwing any errors or bringing it to my attention.
It just fails to connect.
To correct the issue, I simply deleted those two links and re-created them. Worth noting, I used the auto select cable here,
which does not ask which interface you want to use when attaching. Earlier I must have plugged the right side first, and
auto select plugged into 0/0/0.
This time I plugged into left side first.
Now LabC OSPF data is reading out correctly...
LabC
LabC(config)#
router ospf 102
LabC(config-router)#
net 172.16.20.2 0.0.0.0 area 0
LabC(config-router)#
net 172.16.30.1 0.0.0.0 area 0
LabC(config-router)#
net 172.16.40.1 0.0.0.0 area 0
01:33:54: %OSPF-5-ADJCHG: Process 102, Nbr 172.16.20.1
on Serial0/0/0 from LOADING to FULL, Loading Done
LabC#
show ip ospf neighbor
Neighbor ID Pri State Dead Time Address Interface
172.16.20.1 0 FULL/ - 00:00:30 172.16.20.1 Serial0/0/0
LabC#
show ip ospf database
OSPF Router with ID (172.16.40.1) (Process ID 102)
Router Link States (Area 0)
Link ID ADV Router Age Seq# Checksum Link count
172.16.10.1 172.16.10.1 542 0x80000002 0x0067cd 1
172.16.20.1 172.16.20.1 90 0x80000004 0x00a551 3
172.16.40.1 172.16.40.1 37 0x80000004 0x00e47c 4
Net Link States (Area 0)
Link ID ADV Router Age Seq# Checksum
172.16.10.1 172.16.10.1 542 0x80000001 0x00953d
LabC#
show ip ospf interface
Serial0/0/0 is up, line protocol is up
Internet address is 172.16.20.2/24, Area 0
Process ID 102, Router ID 172.16.40.1, Network Type POINT-TO-POINT, Cost: 64
Transmit Delay is 1 sec, State POINT-TO-POINT,
Timer intervals configured, Hello 10, Dead 40, Wait 40, Retransmit 5
Hello due in 00:00:01
Index 1/1, flood queue length 0
Next 0x0(0)/0x0(0)
Last flood scan length is 1, maximum is 1
Last flood scan time is 0 msec, maximum is 0 msec
Neighbor Count is 1 , Adjacent neighbor count is 1
Adjacent with neighbor 172.16.20.1
Suppress hello for 0 neighbor(s)
FastEthernet0/0 is up, line protocol is up
Internet address is 172.16.30.1/24, Area 0
Process ID 102, Router ID 172.16.40.1, Network Type BROADCAST, Cost: 1
Transmit Delay is 1 sec, State DR, Priority 1
Designated Router (ID) 172.16.40.1, Interface address 172.16.30.1
No backup designated router on this network
Timer intervals configured, Hello 10, Dead 40, Wait 40, Retransmit 5
Hello due in 00:00:02
Index 2/2, flood queue length 0
Next 0x0(0)/0x0(0)
Last flood scan length is 1, maximum is 1
Last flood scan time is 0 msec, maximum is 0 msec
Neighbor Count is 0, Adjacent neighbor count is 0
Suppress hello for 0 neighbor(s)
Serial0/0/1 is up, line protocol is up
Internet address is 172.16.40.1/24, Area 0
Process ID 102, Router ID 172.16.40.1, Network Type POINT-TO-POINT, Cost: 64
Transmit Delay is 1 sec, State POINT-TO-POINT,
Timer intervals configured, Hello 10, Dead 40, Wait 40, Retransmit 5
Hello due in 00:00:08
Index 3/3, flood queue length 0
Next 0x0(0)/0x0(0)
Last flood scan length is 1, maximum is 1
Last flood scan time is 0 msec, maximum is 0 msec
Suppress hello for 0 neighbor(s)
Which brings me to the original reason I re-created this topology... I was confused about the LINK COUNTS
here:
OSPF Router with ID (172.16.40.1) (Process ID 102)
Router Link States (Area 0)
Link ID ADV Router Age Seq# Checksum Link count
172.16.10.1 172.16.10.1 542 0x80000002 0x0067cd 1
172.16.20.1 172.16.20.1 90 0x80000004 0x00a551 3
172.16.40.1 172.16.40.1 37 0x80000004 0x00e47c 4
Net Link States (Area 0)
Link ID ADV Router Age Seq# Checksum
172.16.10.1 172.16.10.1 542 0x80000001 0x00953d
The steps of recreating the lab were helpful, but this link answered the question:
Here is the output of each router's command show ip ospf interface as they are
set up one at a time.
LabA - No OSPF at B, C, or D yet
show ip ospf database
OSPF Router with ID (172.16.10.1) (Process ID 100)
Router Link States (Area 0)
Link ID ADV Router Age Seq# Checksum Link count
172.16.10.1 172.16.10.1 44 0x80000001 0x00b24b 1
LabB - No OSPF at C or D yet
show ip ospf database
OSPF Router with ID (172.16.20.1) (Process ID 101)
Router Link States (Area 0)
Link ID ADV Router Age Seq# Checksum Link count
172.16.10.1 172.16.10.1 145 0x80000002 0x0067cd 1
172.16.20.1 172.16.20.1 32 0x80000003 0x006e8f 2
Net Link States (Area 0)
Link ID ADV Router Age Seq# Checksum
172.16.10.1 172.16.10.1 145 0x80000001 0x00953d
the 20.2 interface on this router has 2 ospf links.
The left-facing out to RA, a crossover cable
The right-facing out to RC, a serial cable.
If the solution I found is correct, why is this serial link not being counted twice? The solution (I think)
is revealed after the configuration of the next router...
LabC - No OSPF at D yet
show ip ospf database
OSPF Router with ID (172.16.40.1) (Process ID 102)
Router Link States (Area 0)
Link ID ADV Router Age Seq# Checksum Link count
172.16.10.1 172.16.10.1 542 0x80000002 0x0067cd 1
172.16.20.1 172.16.20.1 90 0x80000004 0x00a551 3
172.16.40.1 172.16.40.1 37 0x80000004 0x00e47c 4
Net Link States (Area 0)
Link ID ADV Router Age Seq# Checksum
172.16.10.1 172.16.10.1 542 0x80000001 0x00953d
NOW we can see that the 20.1 link, which is the right-facing interface on LabB.. aka the router ID..
has THREE OSPF links.
Nothing changed on the left side of B. But on the right side, we now have an active OSPF router at the
other end of the link. This leads me to believe that the forum post was correct that 'serial links are counted twice',
but, more specifically, BOTH ENDS of the serial(PPP) link are counted... IF there is an OSPF router on each end.
This is backed up by the fact that LabC, OSPF id 40.1, has four OSPF links. The top-facing link to the 30
network DOES count.. even though it has no OSPF router on the other end. It counts because it's not a serial link.
The requirement of having an OSPF router on the other end for an interface to count here, only applies
to serial links. And pertains to BOTH ends of the link being counted.
In LabC's case, we have one serial at left, being counted twice. One ethernet at top, being counted once. And
one serial at right only being counted once because LabD is not active with OSPF yet.
If this is correct, then we should see Lab C's 40.1 count go to 5 after LabD is set for OSPF....
LabD - all 4 routers have OSPF
show ip ospf database
OSPF Router with ID (172.16.50.1) (Process ID 103)
Router Link States (Area 0)
Link ID ADV Router Age Seq# Checksum Link count
172.16.10.1 172.16.10.1 785 0x80000002 0x0067cd 1
172.16.20.1 172.16.20.1 333 0x80000004 0x00a551 3
172.16.40.1 172.16.40.1 111 0x80000005 0x00013b 5
172.16.50.1 172.16.50.1 53 0x80000003 0x001023 3
Net Link States (Area 0)
Link ID ADV Router Age Seq# Checksum
172.16.10.1 172.16.10.1 785 0x80000001 0x00953d
and back to LabC.....
show ip ospf database
OSPF Router with ID (172.16.40.1) (Process ID 102)
Router Link States (Area 0)
Link ID ADV Router Age Seq# Checksum Link count
172.16.10.1 172.16.10.1 1174 0x80000002 0x0067cd 1
172.16.20.1 172.16.20.1 722 0x80000004 0x00a551 3
172.16.40.1 172.16.40.1 500 0x80000005 0x00013b 5
172.16.50.1 172.16.50.1 441 0x80000003 0x001023 3
Net Link States (Area 0)
Link ID ADV Router Age Seq# Checksum
172.16.10.1 172.16.10.1 1174 0x80000001 0x00953d
Looks good! The link count for each router makes sense if you count the serial interfaces twice (one for each end).
the OSPF databases now match across all 4 routers.
NOTE that this is a database of routers, identified by
router ID. It is not a topology that lists routers AND routes, like in
the "equivalent" eigrp command show eigrp topology
Note that the .30 network is NOT represented here.
LabA#
show ip ospf database
OSPF Router with ID (172.16.10.1) (Process ID 100)
Router Link States (Area 0)
Link ID ADV Router Age Seq# Checksum Link count
172.16.10.1 172.16.10.1 1138 0x80000002 0x0067cd 1
172.16.20.1 172.16.20.1 686 0x80000004 0x00a551 3
172.16.40.1 172.16.40.1 463 0x80000005 0x00013b 5
172.16.50.1 172.16.50.1 404 0x80000003 0x001023 3
Net Link States (Area 0)
Link ID ADV Router Age Seq# Checksum
172.16.10.1 172.16.10.1 1138 0x80000001 0x00953d
LabB#
show ip ospf database
OSPF Router with ID (172.16.20.1) (Process ID 101)
Router Link States (Area 0)
Link ID ADV Router Age Seq# Checksum Link count
172.16.10.1 172.16.10.1 1151 0x80000002 0x0067cd 1
172.16.20.1 172.16.20.1 699 0x80000004 0x00a551 3
172.16.40.1 172.16.40.1 476 0x80000005 0x00013b 5
172.16.50.1 172.16.50.1 417 0x80000003 0x001023 3
Net Link States (Area 0)
Link ID ADV Router Age Seq# Checksum
172.16.10.1 172.16.10.1 1151 0x80000001 0x00953d
LabC#
show ip ospf database
OSPF Router with ID (172.16.40.1) (Process ID 102)
Router Link States (Area 0)
Link ID ADV Router Age Seq# Checksum Link count
172.16.10.1 172.16.10.1 1174 0x80000002 0x0067cd 1
172.16.20.1 172.16.20.1 722 0x80000004 0x00a551 3
172.16.40.1 172.16.40.1 500 0x80000005 0x00013b 5
172.16.50.1 172.16.50.1 441 0x80000003 0x001023 3
Net Link States (Area 0)
Link ID ADV Router Age Seq# Checksum
172.16.10.1 172.16.10.1 1174 0x80000001 0x00953d
LabD#
show ip ospf database
OSPF Router with ID (172.16.50.1) (Process ID 103)
Router Link States (Area 0)
Link ID ADV Router Age Seq# Checksum Link count
172.16.10.1 172.16.10.1 785 0x80000002 0x0067cd 1
172.16.20.1 172.16.20.1 333 0x80000004 0x00a551 3
172.16.40.1 172.16.40.1 111 0x80000005 0x00013b 5
172.16.50.1 172.16.50.1 53 0x80000003 0x001023 3
Net Link States (Area 0)
Link ID ADV Router Age Seq# Checksum
172.16.10.1 172.16.10.1 785 0x80000001 0x00953d
Below is our routing tables with OSPF data. We do see the .30 network here.
Everyone can reach it:
LabA via LabB's 10.2
LabB via LabC's 20.2
LabC via direct connection
LabD via LabC's 40.1
LabA#
show ip route
172.16.0.0/16 is variably subnetted, 6 subnets, 2 masks
C 172.16.10.0/24 is directly connected, FastEthernet0/0
L 172.16.10.1/32 is directly connected, FastEthernet0/0
O 172.16.20.0/24 [110/65] via 172.16.10.2, 00:28:03, FastEthernet0/0
O 172.16.30.0/24 [110/66] via 172.16.10.2, 00:21:35, FastEthernet0/0
O 172.16.40.0/24 [110/129] via 172.16.10.2, 00:21:25, FastEthernet0/0
O 172.16.50.0/24 [110/130] via 172.16.10.2, 00:17:40, FastEthernet0/0
LabB#
show ip route
172.16.0.0/16 is variably subnetted, 7 subnets, 2 masks
C 172.16.10.0/24 is directly connected, FastEthernet0/0
L 172.16.10.2/32 is directly connected, FastEthernet0/0
C 172.16.20.0/24 is directly connected, Serial0/0/0
L 172.16.20.1/32 is directly connected, Serial0/0/0
O 172.16.30.0/24 [110/65] via 172.16.20.2, 00:27:04, Serial0/0/0
O 172.16.40.0/24 [110/128] via 172.16.20.2, 00:26:54, Serial0/0/0
O 172.16.50.0/24 [110/129] via 172.16.20.2, 00:23:09, Serial0/0/0
LabC#
show ip route
172.16.0.0/16 is variably subnetted, 8 subnets, 2 masks
O 172.16.10.0/24 [110/65] via 172.16.20.1, 00:27:52, Serial0/0/0
C 172.16.20.0/24 is directly connected, Serial0/0/0
L 172.16.20.2/32 is directly connected, Serial0/0/0
C 172.16.30.0/24 is directly connected, FastEthernet0/0
L 172.16.30.1/32 is directly connected, FastEthernet0/0
C 172.16.40.0/24 is directly connected, Serial0/0/1
L 172.16.40.1/32 is directly connected, Serial0/0/1
O 172.16.50.0/24 [110/65] via 172.16.40.2, 00:23:36, Serial0/0/1
LabD#
show ip route
172.16.0.0/16 is variably subnetted, 7 subnets, 2 masks
O 172.16.10.0/24 [110/129] via 172.16.40.1, 00:25:20, Serial0/0/0
O 172.16.20.0/24 [110/128] via 172.16.40.1, 00:25:20, Serial0/0/0
O 172.16.30.0/24 [110/65] via 172.16.40.1, 00:25:20, Serial0/0/0
C 172.16.40.0/24 is directly connected, Serial0/0/0
L 172.16.40.2/32 is directly connected, Serial0/0/0
C 172.16.50.0/24 is directly connected, FastEthernet0/0
L 172.16.50.1/32 is directly connected, FastEthernet0/0
moving on.......
9.5 - OSPF DR and BDR Elections
EachRouter(config)#
hostname X (A, B, or C)
EachRouter(config)#
line con 0
EachRouter(config-line)#
exec-timeout 0 0
A(config)#
int f0/0
A(config-if)#
ip addr 10.1.1.1 255.255.255.0
A(config-if)#
no shut
A(config)#
router ospf 12345
A(config-router)#
net 10.1.1.0 0.0.0.255 area 0
00:23:30: %OSPF-5-ADJCHG: Process 12345, Nbr 10.1.1.3 on FastEthernet0/0 from LOADING to FULL, Loading Done
00:23:30: %OSPF-5-ADJCHG: Process 12345, Nbr 10.1.1.2 on FastEthernet0/0 from LOADING to FULL, Loading Done
A#
show ip ospf int
note this output was generated AFTER all 3 routers set for OSPF
FastEthernet0/0 is up, line protocol is up
Internet address is 10.1.1.1/24, Area 0
Process ID 12345, Router ID 10.1.1.1, Network Type BROADCAST, Cost: 1
Transmit Delay is 1 sec, State DROTHER, Priority 1
Designated Router (ID) 10.1.1.3, Interface address 10.1.1.3
Backup Designated Router (ID) 10.1.1.2, Interface address 10.1.1.2
Timer intervals configured, Hello 10, Dead 40, Wait 40, Retransmit 5
Hello due in 00:00:04
Index 1/1, flood queue length 0
Next 0x0(0)/0x0(0)
Last flood scan length is 1, maximum is 1
Last flood scan time is 0 msec, maximum is 0 msec
Neighbor Count is 2, Adjacent neighbor count is 2
Adjacent with neighbor 10.1.1.3 (Designated Router)
Adjacent with neighbor 10.1.1.2 (Backup Designated Router)
Suppress hello for 0 neighbor(s)
A(config-if)#shut
A(config-if)#
%LINK-5-CHANGED: Interface FastEthernet0/0, changed state to administratively down
%LINEPROTO-5-UPDOWN: Line protocol on Interface FastEthernet0/0, changed state to down
00:40:28: %OSPF-5-ADJCHG: Process 12345, Nbr 10.1.1.2 on FastEthernet0/0 from FULL to DOWN, Neighbor Down: Interface down or detached
00:40:28: OSPF: Build router LSA for area 0, router ID 10.1.1.1, seq 0xffffffff80000003
00:40:28: %OSPF-5-ADJCHG: Process 12345, Nbr 10.1.1.3 on FastEthernet0/0 from FULL to DOWN, Neighbor Down: Interface down or detached
00:40:28: OSPF: Build router LSA for area 0, router ID 10.1.1.1, seq 0xffffffff80000004
00:40:28: OSPF: Build router LSA for area 0, router ID 10.1.1.1, seq 0xffffffff80000004
A(config-if)#no shut
A(config-if)#
%LINK-5-CHANGED: Interface FastEthernet0/0, changed state to up
%LINEPROTO-5-UPDOWN: Line protocol on Interface FastEthernet0/0, changed state to up
00:40:48: OSPF: Build router LSA for area 0, router ID 10.1.1.1, seq 0xffffffff80000004
00:41:27: OSPF: Backup seen Event before WAIT timer on FastEthernet0/0
00:41:27: OSPF: DR/BDR election on FastEthernet0/0
00:41:27: OSPF: Elect BDR 10.1.1.2
00:41:27: OSPF: Elect DR 10.1.1.3
00:41:27: DR: 10.1.1.3 (Id) BDR: 10.1.1.2 (Id)
00:41:27: OSPF: Send DBD to 10.1.1.3 on FastEthernet0/0 seq 0x5accb8e2 opt 0x00 flag 0x7 len 32
B(config)#
int f0/0
B(config-if)#
ip addr 10.1.1.2 255.255.255.0
B(config-if)#
no shut
B(config)#
router ospf 12345
B(config-router)#
net 10.1.1.0 0.0.0.255 area 0
00:23:29: %OSPF-5-ADJCHG: Process 12345, Nbr 10.1.1.3 on FastEthernet0/0 from LOADING to FULL, Loading Done
00:23:29: %OSPF-5-ADJCHG: Process 12345, Nbr 10.1.1.1 on FastEthernet0/0 from LOADING to FULL, Loading Done
B#
show ip ospf int
note this output was generated AFTER all 3 routers set for OSPF
FastEthernet0/0 is up, line protocol is up
Internet address is 10.1.1.2/24, Area 0
Process ID 12345, Router ID 10.1.1.2, Network Type BROADCAST, Cost: 1
Transmit Delay is 1 sec, State BDR, Priority 1
Designated Router (ID) 10.1.1.3, Interface address 10.1.1.3
Backup Designated Router (ID) 10.1.1.2, Interface address 10.1.1.2
Timer intervals configured, Hello 10, Dead 40, Wait 40, Retransmit 5
Hello due in 00:00:05
Index 1/1, flood queue length 0
Next 0x0(0)/0x0(0)
Last flood scan length is 1, maximum is 1
Last flood scan time is 0 msec, maximum is 0 msec
Neighbor Count is 2, Adjacent neighbor count is 2
Adjacent with neighbor 10.1.1.1
Adjacent with neighbor 10.1.1.3 (Designated Router)
Suppress hello for 0 neighbor(s)
B#debug ip ospf adj
OSPF adjacency events debugging is on
B#
00:39:21: OSPF: DR/BDR election on FastEthernet0/0
00:39:21: OSPF: Elect BDR 10.1.1.2
00:39:21: OSPF: Elect DR 10.1.1.3
00:39:21: DR: 10.1.1.3 (Id) BDR: 10.1.1.2 (Id)
00:41:01: %OSPF-5-ADJCHG: Process 12345, Nbr 10.1.1.1 on FastEthernet0/0 from FULL to DOWN, Neighbor Down: Dead timer expired
00:41:01: %OSPF-5-ADJCHG: Process 12345, Nbr 10.1.1.1 on FastEthernet0/0 from FULL to DOWN, Neighbor Down: Interface down or detached
00:41:01: OSPF: Build router LSA for area 0, router ID 10.1.1.2, seq 0xffffffff80000003
00:41:01: OSPF: DR/BDR election on FastEthernet0/0
00:41:01: OSPF: Elect BDR 10.1.1.2
00:41:01: OSPF: Elect DR 10.1.1.3
C(config)#
int f0/0
C(config-if)#
ip addr 10.1.1.3 255.255.255.0
C(config-if)#
no shut
C(config)#
router ospf 12345
C(config-router)#
net 10.1.1.0 0.0.0.255 area 0
00:23:27: %OSPF-5-ADJCHG: Process 12345, Nbr 10.1.1.1 on FastEthernet0/0 from LOADING to FULL, Loading Done
00:23:27: %OSPF-5-ADJCHG: Process 12345, Nbr 10.1.1.2 on FastEthernet0/0 from LOADING to FULL, Loading Done
C#
show ip ospf int
note this output was generated AFTER all 3 routers set for OSPF
FastEthernet0/0 is up, line protocol is up
Internet address is 10.1.1.3/24, Area 0
Process ID 12345, Router ID 10.1.1.3, Network Type BROADCAST, Cost: 1
Transmit Delay is 1 sec, State DR, Priority 1
Designated Router (ID) 10.1.1.3, Interface address 10.1.1.3
Backup Designated Router (ID) 10.1.1.2, Interface address 10.1.1.2
Timer intervals configured, Hello 10, Dead 40, Wait 40, Retransmit 5
Hello due in 00:00:00
Index 1/1, flood queue length 0
Next 0x0(0)/0x0(0)
Last flood scan length is 1, maximum is 1
Last flood scan time is 0 msec, maximum is 0 msec
Neighbor Count is 2, Adjacent neighbor count is 2
Adjacent with neighbor 10.1.1.1
Adjacent with neighbor 10.1.1.2 (Backup Designated Router)
Suppress hello for 0 neighbor(s)
C#debug ip ospf adj
OSPF adjacency events debugging is on
C#
00:39:19: OSPF: DR/BDR election on FastEthernet0/0
00:39:19: OSPF: Elect BDR 10.1.1.2
00:39:19: OSPF: Elect DR 10.1.1.3
00:39:19: DR: 10.1.1.3 (Id) BDR: 10.1.1.2 (Id)
00:40:59: %OSPF-5-ADJCHG: Process 12345, Nbr 10.1.1.1 on FastEthernet0/0 from FULL to DOWN, Neighbor Down: Dead timer expired
00:40:59: %OSPF-5-ADJCHG: Process 12345, Nbr 10.1.1.1 on FastEthernet0/0 from FULL to DOWN, Neighbor Down: Interface down or detached
00:40:59: OSPF: Build router LSA for area 0, router ID 10.1.1.3, seq 0xffffffff80000003
00:40:59: OSPF: Build net LSA for area 0, router ID 10.1.1.3, seq 0xffffffff80000003
00:40:59: OSPF: DR/BDR election on FastEthernet0/0
00:40:59: OSPF: Elect BDR 10.1.1.2
00:40:59: OSPF: Elect DR 10.1.1.3
DR and BDR automtically set based on higest IP address
Note our network type is BROADCAST because we're using ethernet interfaces...
it would be point-to-point if using a serial connection
we want to manually overide the priority of the router. ZERO priority means it wont participate in the election process
MAX priority of 255 means no other router can beat it for DR
We'll set the priority for router A to 3.
It will beome the DR only after we shut/no shut the interface router
AND
manually power on/off the other two routers
A(config)#
int f0/0
A(config-int)#
ip ospf priority 3
A(config-int)#
shut
A(config-int)#
no shut
A#
debug ip ospf adj
B#
debug ip ospf adj
00:05:50: OSPF: DR/BDR election on FastEthernet0/0
00:05:50: OSPF: Elect BDR 10.1.1.2
00:05:50: OSPF: Elect DR 10.1.1.1
00:05:50: OSPF: Elect BDR 10.1.1.2
00:05:50: OSPF: Elect DR 10.1.1.1
00:05:50: DR: 10.1.1.1 (Id) BDR: 10.1.1.2 (Id)
00:05:50: OSPF: Send DBD to 10.1.1.1 on FastEthernet0/0 seq 0x10164ebb opt 0x00 flag 0x7 len 32
00:05:50: OSPF: Build router LSA for area 0, router ID 10.1.1.2, seq 0xffffffff80000002
00:05:52: OSPF: Rcv DBD from 10.1.1.1 on FastEthernet0/0 seq 0x20368093 opt 0x00 flag 0x7 len 32 mtu 1500 state EXSTART
00:05:52: OSPF: First DBD and we are not SLAVE
00:05:55: OSPF: Send DBD to 10.1.1.1 on FastEthernet0/0 seq 0x10164ebb opt 0x00 flag 0x7 len 32
00:05:55: OSPF: Rcv DBD from 10.1.1.1 on FastEthernet0/0 seq 0x10164ebb opt 0x00 flag 0x2 len 112 mtu 1500 state EXSTART
00:05:55: OSPF: NBR Negotiation Done. We are the MASTER
00:05:55: OSPF: Send DBD to 10.1.1.1 on FastEthernet0/0 seq 0x10164ebc opt 0x00 flag 0x3 len 52
00:05:55: OSPF: Rcv DBD from 10.1.1.1 on FastEthernet0/0 seq 0x10164ebc opt 0x00 flag 0x0 len 32 mtu 1500 state EXCHANGE
00:05:55: OSPF: Send DBD to 10.1.1.1 on FastEthernet0/0 seq 0x10164ebd opt 0x00 flag 0x1 len 32
00:05:55: OSPF: Rcv DBD from 10.1.1.1 on FastEthernet0/0 seq 0x10164ebd opt 0x00 flag 0x0 len 32 mtu 1500 state EXCHANGE
00:05:55: Exchange Done with 10.1.1.1 on FastEthernet0/0
00:05:55: OSPF: Database request to 10.1.1.1
00:05:55: OSPF: sent LS REQ packet to 10.1.1.1, length 36
00:05:55: OSPF: Rcv DBD from 10.1.1.1 on FastEthernet0/0 seq 0x10164ebd opt 0x00 flag 0x0 len 32 mtu 1500 state LOADING
00:05:55: Synchronized with with 10.1.1.1 on FastEthernet0/0, state FULL
00:05:55: %OSPF-5-ADJCHG: Process 12345, Nbr 10.1.1.1 on FastEthernet0/0 from LOADING to FULL, Loading Done
00:05:55: OSPF: Build router LSA for area 0, router ID 10.1.1.2, seq 0xffffffff80000002
C#
debug ip ospf adj
00:06:13: OSPF: DR/BDR election on FastEthernet0/0
00:06:13: OSPF: Elect BDR 10.1.1.2
00:06:13: OSPF: Elect DR 10.1.1.1
00:06:13: DR: 10.1.1.1 (Id) BDR: 10.1.1.2 (Id)
00:06:13: OSPF: Send DBD to 10.1.1.1 on FastEthernet0/0 seq 0x1cc5536d opt 0x00 flag 0x7 len 32
00:06:13: OSPF: Send DBD to 10.1.1.2 on FastEthernet0/0 seq 0x3d51ca66 opt 0x00 flag 0x7 len 32
00:06:13: OSPF: Build router LSA for area 0, router ID 10.1.1.3, seq 0xffffffff80000002
00:06:17: OSPF: Rcv DBD from 10.1.1.1 on FastEthernet0/0 seq 0x6b532eec opt 0x00 flag 0x7 len 32 mtu 1500 state EXSTART
00:06:17: OSPF: First DBD and we are not SLAVE
00:06:17: OSPF: Rcv DBD from 10.1.1.2 on FastEthernet0/0 seq 0x783110f4 opt 0x00 flag 0x7 len 32 mtu 1500 state EXSTART
00:06:17: OSPF: First DBD and we are not SLAVE
00:06:18: OSPF: Send DBD to 10.1.1.2 on FastEthernet0/0 seq 0x3d51ca66 opt 0x00 flag 0x7 len 32
00:06:18: OSPF: Send DBD to 10.1.1.1 on FastEthernet0/0 seq 0x1cc5536d opt 0x00 flag 0x7 len 32
00:06:18: OSPF: Rcv DBD from 10.1.1.2 on FastEthernet0/0 seq 0x3d51ca66 opt 0x00 flag 0x2 len 132 mtu 1500 state EXSTART
00:06:18: OSPF: NBR Negotiation Done. We are the MASTER
00:06:18: OSPF: Send DBD to 10.1.1.2 on FastEthernet0/0 seq 0x3d51ca67 opt 0x00 flag 0x3 len 52
00:06:18: OSPF: Rcv DBD from 10.1.1.1 on FastEthernet0/0 seq 0x1cc5536d opt 0x00 flag 0x2 len 132 mtu 1500 state EXSTART
00:06:18: OSPF: NBR Negotiation Done. We are the MASTER
00:06:18: OSPF: Send DBD to 10.1.1.1 on FastEthernet0/0 seq 0x1cc5536e opt 0x00 flag 0x3 len 52
00:06:18: OSPF: Rcv DBD from 10.1.1.2 on FastEthernet0/0 seq 0x3d51ca67 opt 0x00 flag 0x0 len 32 mtu 1500 state EXCHANGE
00:06:18: OSPF: Send DBD to 10.1.1.2 on FastEthernet0/0 seq 0x3d51ca68 opt 0x00 flag 0x1 len 32
00:06:18: OSPF: Rcv DBD from 10.1.1.1 on FastEthernet0/0 seq 0x1cc5536e opt 0x00 flag 0x0 len 32 mtu 1500 state EXCHANGE
00:06:18: OSPF: Send DBD to 10.1.1.1 on FastEthernet0/0 seq 0x1cc5536f opt 0x00 flag 0x1 len 32
00:06:18: OSPF: Rcv DBD from 10.1.1.2 on FastEthernet0/0 seq 0x3d51ca68 opt 0x00 flag 0x0 len 32 mtu 1500 state EXCHANGE
00:06:18: Exchange Done with 10.1.1.2 on FastEthernet0/0
00:06:18: OSPF: Database request to 10.1.1.2
00:06:18: OSPF: sent LS REQ packet to 10.1.1.2, length 48
00:06:18: OSPF: Rcv DBD from 10.1.1.1 on FastEthernet0/0 seq 0x1cc5536f opt 0x00 flag 0x0 len 32 mtu 1500 state EXCHANGE
verify on all three routers
A#
show ip ospf interface f0/0
FastEthernet0/0 is up, line protocol is up
Internet address is 10.1.1.1/24, Area 0
Process ID 12345, Router ID 10.1.1.1, Network Type BROADCAST, Cost: 1
Transmit Delay is 1 sec, State DR, Priority 3
Designated Router (ID) 10.1.1.1, Interface address 10.1.1.1
Backup Designated Router (ID) 10.1.1.2, Interface address 10.1.1.2
Timer intervals configured, Hello 10, Dead 40, Wait 40, Retransmit 5
Hello due in 00:00:09
Index 1/1, flood queue length 0
Next 0x0(0)/0x0(0)
Last flood scan length is 1, maximum is 1
Last flood scan time is 0 msec, maximum is 0 msec
Neighbor Count is 2, Adjacent neighbor count is 2
Adjacent with neighbor 10.1.1.2 (Backup Designated Router)
Adjacent with neighbor 10.1.1.3
Suppress hello for 0 neighbor(s)
A#
show ip ospf neighbor
Neighbor ID Pri State Dead Time Address Interface
10.1.1.2 1 FULL/BDR 00:00:37 10.1.1.2 FastEthernet0/0
10.1.1.3 1 FULL/DROTHER 00:00:30 10.1.1.3 FastEthernet0/0
B#
show ip ospf interface f0/0
FastEthernet0/0 is up, line protocol is up
Internet address is 10.1.1.2/24, Area 0
Process ID 12345, Router ID 10.1.1.2, Network Type BROADCAST, Cost: 1
Transmit Delay is 1 sec, State BDR, Priority 1
Designated Router (ID) 10.1.1.1, Interface address 10.1.1.1
Backup Designated Router (ID) 10.1.1.2, Interface address 10.1.1.2
Timer intervals configured, Hello 10, Dead 40, Wait 40, Retransmit 5
Hello due in 00:00:08
Index 1/1, flood queue length 0
Next 0x0(0)/0x0(0)
Last flood scan length is 1, maximum is 1
Last flood scan time is 0 msec, maximum is 0 msec
Neighbor Count is 2, Adjacent neighbor count is 2
Adjacent with neighbor 10.1.1.1 (Designated Router)
Adjacent with neighbor 10.1.1.3
Suppress hello for 0 neighbor(s)
B#
show ip ospf neighbor
Neighbor ID Pri State Dead Time Address Interface
10.1.1.1 3 FULL/DR 00:00:35 10.1.1.1 FastEthernet0/0
10.1.1.3 1 FULL/DROTHER 00:00:31 10.1.1.3 FastEthernet0/0
C#
show ip ospf interface f0/0
FastEthernet0/0 is up, line protocol is up
Internet address is 10.1.1.3/24, Area 0
Process ID 12345, Router ID 10.1.1.3, Network Type BROADCAST, Cost: 1
Transmit Delay is 1 sec, State DROTHER, Priority 1
Designated Router (ID) 10.1.1.1, Interface address 10.1.1.1
Backup Designated Router (ID) 10.1.1.2, Interface address 10.1.1.2
Timer intervals configured, Hello 10, Dead 40, Wait 40, Retransmit 5
Hello due in 00:00:06
Index 1/1, flood queue length 0
Next 0x0(0)/0x0(0)
Last flood scan length is 1, maximum is 1
Last flood scan time is 0 msec, maximum is 0 msec
Neighbor Count is 2, Adjacent neighbor count is 2
Adjacent with neighbor 10.1.1.1 (Designated Router)
Adjacent with neighbor 10.1.1.2 (Backup Designated Router)
Suppress hello for 0 neighbor(s)
C#
show ip ospf neighbor/span>
Neighbor ID Pri State Dead Time Address Interface
10.1.1.1 3 FULL/DR 00:00:35 10.1.1.1 FastEthernet0/0
10.1.1.2 1 FULL/BDR 00:00:37 10.1.1.2 FastEthernet0/0
Router1 is the DR with priority 3
still need more work to understand the output of the defbu ospf adj
Chapter 9 Review Questions
1. There are three possible routes for a router to reach a destination network:
OSPF with a metric of 782
RIPv2 with a metric of 4
EIGRP with a composite metric of 20514560
Which route will be installed in the routing table?
EIGRP because it has the lowest Administrative Distance, and AD is always used before metric
ADs are:
ExternalEIGRP 170
RIP 120
OSPF 110
IGRP 100
EIGRP 90
Static 1
Connected 0
2. Which EIGRP information is held in RAM and maintained through the use of Hello and update packets?
Neighbor table
and
toplogy table
3. Describe the process identifier that is used to run OSPF on a router
The OSPF process id is only locally significant. A random number can be selected. But it's required in order to identify
a unique OSPF database instance. You can use the same, or a different number on each router, doesnt matter.
Any number can be used from 1 to 65,535. Process ID is supplied as an argument to the command router ospf
NOT to be confused with the area number which can be any number up to 4 billion. The area id identifies a logical grouping of routers.
area id is supplied as argument to the OSPF network id and mask command
Ex:
R1(config)#
router ospf 12345
R1(config-router)#
net 10.1.1.0 0.0.0.255 area 0
4. Where are EIGRP successor routes stored?
EIGRP succesor routers are stored in the routing table. The "succesor" is the successful or primary route.
The successor route is ALSO listed in the topology table,
The feasible successor is a BACKUP route and will ONLY be listed in the topology table, unless the successor route fails,
in which case the feasible successor would become the successor
Note that my EIGRP setup doesnt seem to folow this.
CTRL-F jump to "remotely connected via remote ingress ip address"
the book states that EIGRP is automatically load-balancing our two links from R1 to corp.. is this why there is no feasible successor here?
I did some research and found that in our case, we are not using a Feasible Successor. You CAN have two Successors with equal metric, in which case EIGRP will
automatically load-balance.
But I wanted to find out what a Feasible Successor actually looks like in the EIGRP topology table..
Kevin Wallace EIGRP article
Conclusion:
EIGRP topology table wouldnt specifically say "Feasible Successor", but you would know by two routes appearing, one with a lower metric.
In my topology we have two equal-metric links and they are both considered "Successors". EIGRP uses them equally (load-balanced)
Corp#
show ip eigrp toplogy
[cut]
P 172.16.10.0/24, 1 successors, FD is 28160
via 10.1.5.2 (28160/25600), FastEthernet0/0
P 192.168.10.0/24, 2 successors, FD is 2172416
via 10.1.3.2 (2172416/28160), Serial0/0/1
via 10.1.2.2 (2172416/28160), Serial0/0/0
P 192.168.20.0/24, 2 successors, FD is 2172416
via 10.1.3.2 (2172416/28160), Serial0/0/1
via 10.1.2.2 (2172416/28160), Serial0/0/0
P 192.168.30.0/24, 1 successors, FD is 2172416
via 10.1.4.2 (2172416/28160), Serial0/1/0
P 192.168.40.0/24, 1 successors, FD is 2172416
via 10.1.4.2 (2172416/28160), Serial0/1/0
5. Which command will display all the EIGRP feasible successor routes to a known router.
show ip eigrp topology
6. Find the configuration error. You type the following into your router, but dont see any routes in the routing table?
Router(config)#
router ospf 1
Router(config-router)#
network 10.0.0.0 255.0.0.0
wrong wildcard mask
instead, could have used
0.255.255.255
or
0.0.0.255
the point is we need to specify the first octet as "allowed" into our OSPF config with a 0 mask.
The remaining bits are 'dont care' bits aka 'wildcard' aka 255
7. Which three protocols support VLSM, summarization, and discontigous networking?
RIPv2
EIGRP
OSPF
all 3 build and mainting routing tables, provide classless routing which allows VLSM, summarization, and discontigous networks
RIPv1 and IGRP build/maintain routing tables, but dont offer classless routing
8. Which are true regarding OSPF areas?
the 'backbone' is area 0
if using other areas, they all must directly connect to area 0
9. Which two network types have a designated router and a backup designated router?
Broadcast
NBMA- Non broadcast multi access. Ex: Frame Relay
network types that DO NOT use DR/BDR:
point to point
broadcast multipoint
10. You need to configure a router with a distance-vector protocol that allows classless routing. Which to use?
EIGRP is considered 'advanced distance vector' (ripv2 wasnt an option)
11. You need the IP address of the devices with which the router has established an adjacency.
Also, the retransmit interval and the queue counts for the adjacent routers need to be checked. What command will display the required information?
show ip eigrp neighbors
WRONG: show ip eigrp adjacency - there is no such command.. the word 'adjacency' is only used with debug ip OSPF adjacency
here are the possible commands for show ip eigrp and debug ip eigrp
show ip eigrp ?
interfaces IP-EIGRP interfaces
neighbors IP-EIGRP neighbors
topology IP-EIGRP Topology Table
traffic IP-EIGRP Traffic Statistics
debug ip eigrp ?
summary IP-EIGRP summary route processing
12. You cant establish an adjacency relationship on a common ethernet link between two routers. Based on the output below, what is the cause of the problem?
RouterA#
Ethernet0/0 is up, line protocol is up
Internet Address 172.16.1.2/16, Area 0
Process ID 2, Router ID 172.126.1.2, Network Type BROADCAST, Cost: 10
Transmit Delay is 1 sec, State DR, Priority 1
Designated Router (ID) 172.16.1.2, interface address 172.16.1.1.
No backup designated router on this network
Timer intervals configured, Hello 5, Dead 20, Wait 20, Retransmit 5
Router B#
Internet Address 172.16.1.1/16, Area 0
Process ID 2, Router ID 172.126.1.1, Network Type BROADCAST, Cost: 10
Transmit Delay is 1 sec, State DR, Priority 1
Designated Router (ID) 172.16.1.1, interface address 172.16.1.2.
No backup designated router on this network
Timer intervals configured, Hello 10, Dead 40, Wait 40, Retransmit 5
mismatched timer intervals
OSPF default Hello is 10 and Dead is 40... RouterA was modified
13. Which is true regarding EIGRP successor routes?
Used in the routing table
also appears in the topolgy table
may (or may not) have a backup feasabile successor
14. Which type of OSPF network will elect a backup designated router?
broadcast multi-access
non-broadcast multiaccess
types of network that will NOT elect a BDR:
point to point and brodacast multipoint (hub/spoke topology)
15. Which two commands will place network 10.2.3.0/24 into area 0?
Router(config)#
router ospf 10
Router(config-router)#
network 10.2.3.0 0.0.0.255 area 0
16. With which network type will OSPF establish router adjacencies but not perform the DR/BDR election process?
Point to point
no election process occurs, there is never a DR on point to point
17. What are three reasons for creating OSPF in a heirarchical design?
decrease routing overhead
speed up convergence
confine stability to single areas of the network
18. What is the administrative distance of OSPF?
110
19.
no auto summary
the network is considered discontigous because we have two classful network subnetted (on the left and right),
seperated by a different classful address.
if auto summarization is taking place, the routers cant determine which side is which because both sides would be summarized as
Class B, 172.16.0.0, which isnt specific enough to distinguish between the sides.
20. IF routers in a single area are configured with the same priority value, what value does a router use for the OSPF router ID in the absence of a loopback interface?
The highest IP of any PHSYICAL interface.
Trick question. Highest IP of any LOGICAL interface is an option. And is correct IF you had logical interfaces, but the question
states that any "logical interfaces are absent".
At OSPF startup, the highest IP of *any* active interface on the router becomes the OSPF router ID. If you have loopback (logical) interfaces configured,
one of them (the largest IP) will *override* the phsyical interfaces and the loopback IP becomes the RID.
Reference for which loopback (if multiple) wins:
packetpushers.net
------------------------------------------------------------------------------
END CHAPTER 9
41 hours 2-14 thru 2-28-22
original total 184 hours
14 hours review 12-26 thru 12-28-22
review total hours 46
book page 502/822
184 + 46 = 230 hours * 60 = (13,800 min) / 500 pages =
avg 28 min/page (includes reading and exercises/labs + online research)
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1. Describe the Basic IP routing process
frame changes at each hop, but packet doesnt change EXCEPT that the TTL field in the IP header decrements
2. List the information required by a router to successfully route packets
destination IP address, location of other routers, possible routers to all remote networks,
the best route to each network, how to maintain and maintain routing info
3. Describe how MAC addresses are used during the routing process
a MAC will never pass a router interface. MACs will change between router interfaces
4. View and interpret the routing table of a router
use show ip route to see the table
a "C" indicates directly connected, an "R" indicates RIP provided the route info, "S" means static
a "C" indicates directly connected, an "R" indicates RIP provided the route info, "S" means static
5. differentiate the three types of routing
static- manually configured
dynamic- routers automatically share info via protocol
default- a special route is configured for all traffic without a more specific destination network found in the table
dynamic- routers automatically share info via protocol
default- a special route is configured for all traffic without a more specific destination network found in the table
6. Compare and contrast static and dynamic routing
static routing creates no routing update traffic which means less overhead on the routers and links- but it must be
configured manually and can't react if links are lost.
dynamic routing creates update traffic, but it can react to outages and choose the best route when multiple routes exist to the same network
dynamic routing creates update traffic, but it can react to outages and choose the best route when multiple routes exist to the same network
7. Configure static routes at the CLI
route [dest network] [mask] [next hop address OR exit interface] [admin distance] [permanent]
Ex:
Corp(config)# ip route 192.168.10.0 255.255.255.0 10.1.2.2 150
Ex:
Corp(config)# ip route 192.168.10.0 255.255.255.0 10.1.2.2 150
8. Create a default route
ip route 0.0.0.0 0.0.0.0 [ip address OR exit interface]
Ex:
R3(config)# ip route 0.0.0.0 0.0.0.0 10.1.5.1 (ingress at Corp router- use if R3 cant identify route)
Ex:
R3(config)# ip route 0.0.0.0 0.0.0.0 10.1.5.1 (ingress at Corp router- use if R3 cant identify route)
9. Understand administrative distance and its role in the selection of the best route
an integer from 0 (most trusted) to 255 (no traffic will pass via this route).
All routing protocols are assigned an AD but it can be changed at the CLI
All routing protocols are assigned an AD but it can be changed at the CLI
10. Differentiate distance-vector, link-state, and hybrid routing protocols
distance vector- based on hop count (RIP)
link-state- multiple factors such as bandwidth and delay
hybrid- uses both
link-state- multiple factors such as bandwidth and delay
hybrid- uses both
11. List mechanisms used to prevent routing loops in the network
max hop count, split horizon, route poisoning, holddown counters
12. Describe the counts used the operation of RIP
route update timer- (30) interval between routing updates
route invalid timer- (180, update x 3) before a route is determined invalid
holddown timer-(180) time info is supressed when a link is lost
route flush timer- (240) seconds before invalid and removal
route invalid timer- (180, update x 3) before a route is determined invalid
holddown timer-(180) time info is supressed when a link is lost
route flush timer- (240) seconds before invalid and removal
13. Configure RIP routing
router rip
network x.x.x.x
the network(s) you want to advertise from your router. It only works if the other router has RIP enabled.
By enabling RIP, you are able to RECEIVE RIP data from other RIP routers.
by specifying a network, you are SENDING RIP data on that network
network x.x.x.x
the network(s) you want to advertise from your router. It only works if the other router has RIP enabled.
By enabling RIP, you are able to RECEIVE RIP data from other RIP routers.
by specifying a network, you are SENDING RIP data on that network
14. Identify commands used to verify RIP routing
show ip route will provide contents of the routing table with codes (R, C, S)
debug ip rip will show RIP updates being sent and received
debug ip rip will show RIP updates being sent and received
15. Describe the differences between RIPv1 and RIPv2
RIPv1 sends a broadcast (255.255.255.255) every 30 seconds and has an AD of 120.
RIPv1 is classful only, does not send any mask info. No authentication between routers.
RIPv2 sends multicasts (224.0.0.9) every 30 seconds and sends mask info, which allows it to support classless networking, RIPv2 also supports autentication between routers.
RIPv2 sends multicasts (224.0.0.9) every 30 seconds and sends mask info, which allows it to support classless networking, RIPv2 also supports autentication between routers.
1. At the appropriate prompt, create a static route to network 172.16.10.0/24 with a next-hop
gateway of 172.16.20.1 and an administrative distance of 150.
Router(config)#
ip route 172.16.10.0 255.255.255.0 172.16.20.1 150
2. When a PC sends a packet to another PC in a remote network, what destination IP address and MAC address will
be in the frame that it sends to it's default gateway?
the gateway interface MAC and the remote PC's IP
3. At the appropriate prompt, create a default route to 172.16.40.1
Router(config)#
ip route 0.0.0.0 0.0.0.0 172.16.40.1
"to" is the wrong word.. we are going TO any route VIA 172.16.40.1
"to" is the wrong word.. we are going TO any route VIA 172.16.40.1
4. If you are using default routing in a classless environment, what command must also be used?
Router(config)#
ip classless
5. On which type of network is a default route most beneficial?
stub
6. At the appropriate prompt, display the routing table on your router
Router#
show ip route
7. When creating a static or default route, you dont have to use the next-hop ip address;
you can instead use the ____________
exit interface
8. True/False: To reach a destination host, you must know the MAC address of the remote host
false, you need the MAC of your router
9. True/False: To reach a destination host, you must know the IP address of the remote host
true
10. At the appropriate prompt, execute the command required on a DCE serial interface that is not required
on a DTE serial interface
Router(config-if)#
clock rate X
11. At the appropriate prompt, enable RIP routing on the interface with the IP address 10.0.0.1/24
Router(config)#
router rip
Router(config-router)# network 10.0.0.0
RIPv1 is CLASSFUL only... use the classful mask based on the first octet given
Router(config-router)# network 10.0.0.0
RIPv1 is CLASSFUL only... use the classful mask based on the first octet given
12. At the appropriate prompt, prevent a router from propagating IP information out serial 1
Router(config)#
router rip
Router(config-router)# passive-interface S0/1
can receive RIP data but will not send
Router(config-router)# passive-interface S0/1
can receive RIP data but will not send
13. What routing loop prevention mechanism sends out a maximum hop count as soon as a link fails?
route poisoning
14. What routing loop prevention mechanism suppresses the resending of routing information to an interface
through which it was received?
split horizon
15. At the appropriate prompt display RIP routing updates as they are sent and received on the router
to the console session
Router#
debug ip rip
to turn it off:
Router# undebug all
to turn it off:
Router# undebug all
Chapter 8 Hands-on Labs
For these labs we will need a network with three routers.
Lab 8.1 Creating Static routes
first set the interfaces, then program the static routes
LabA(config)#
int s0/0/0
LabA(config-if)#
ip addr 172.16.20.1
LabA(config-if)#
int f0/0
LabA(config-if)#
ip addr 172.16.10.1
-----------------------------------------------------------------
LabA(config)#
ip route 172.16.30.0 255.255.255.0 172.16.20.2
LabA(config)#
ip route 172.16.40.0 255.255.255.0 172.16.20.2
LabB(config)#
int s0/0/0
LabB(config-if)#
ip addr 172.16.20.2
LabB(config-if)#
int s0/0/1
LabB(config-if)#
ip addr 172.16.30.1
-----------------------------------------------------------------
LabB(config)#
ip route 172.16.10.0 255.255.255.0 172.16.20.1
LabB(config)#
ip route 172.16.40.0 255.255.255.0 172.16.30.2
LabC(config)#
int s0/0/0
LabC(config-if)#
ip addr 172.16.30.2
LabC(config-if)#
int f0/0
LabC(config-if)#
ip addr 172.16.40.1
-----------------------------------------------------------------
LabC(config)#
ip route 172.16.10.0 255.255.255.0 172.16.30.1
LabC(config)#
ip route 172.16.20.0 255.255.255.0 172.16.30.1
Lab 8.2 RIP Configuration
remove the static routes, enable and configure RIP with the classful network id that covers the routes you want to advertise
LabA(config)#
no ip route 172.16.30.0 255.255.255.0 172.16.20.2
LabA(config)#
no ip route 172.16.40.0 255.255.255.0 172.16.20.2
LabA(config)#
router rip
LabA(config-router)#
network 172.16.0.0
LabA(config-router)#
do show ip route
Gateway of last resort is not set
172.16.0.0/16 is variably subnetted, 5 subnets, 2 masks
C 172.16.10.0/24 is directly connected, FastEthernet0/0
L 172.16.10.1/32 is directly connected, FastEthernet0/0
C 172.16.20.0/24 is directly connected, Serial0/0/0
L 172.16.20.1/32 is directly connected, Serial0/0/0
R 172.16.30.0/24 [120/1] via 172.16.20.2, 00:00:07, Serial0/0/0
from Lab B
LabB(config)#
no ip route 172.16.10.0 255.255.255.0 172.16.20.1
LabB(config)#
no ip route 172.16.40.0 255.255.255.0 172.16.30.2
LabB(config)#
router rip
LabB(config-router)#
network 172.16.0.0
LabB(config-router)#
do show ip route
Gateway of last resort is not set
172.16.0.0/16 is variably subnetted, 5 subnets, 2 masks
R 172.16.10.0/24 [120/1] via 172.16.20.1, 00:00:13, Serial0/0/0
from LabA
C 172.16.20.0/24 is directly connected, Serial0/0/0
L 172.16.20.2/32 is directly connected, Serial0/0/0
C 172.16.30.0/24 is directly connected, Serial0/0/1
L 172.16.30.1/32 is directly connected, Serial0/0/1
LabC(config)#
no ip route 172.16.10.0 255.255.255.0 172.16.30.1
LabC(config)#
no ip route 172.16.20.0 255.255.255.0 172.16.30.1
LabC(config)#
router rip
LabC(config-router)#
network 172.16.0.0
LabC(config-router)#
do show ip route
Gateway of last resort is not set
172.16.0.0/16 is variably subnetted, 3 subnets, 2 masks
R 172.16.20.0/24 [120/1] via 172.16.30.1, 00:00:05, Serial0/0/0
from LabB
C 172.16.30.0/24 is directly connected, Serial0/0/0
L 172.16.30.2/32 is directly connected, Serial0/0/0
Chapter 8 Review Questions
1. The Acme company uses a router named Gateway to connect to its ISP. The address of the ISP router is 206.143.5.2.
Which three commands could be configured on the gateway router to allow internet access to the entire network?
Set a default route:
Gateway(config)#
ip route 0.0.0.0 0.0.0.0 206.143.5.2 next hop IP
Gateway(config)#
ip route 0.0.0.0 0.0.0.0 S/0 exit interface instead of next hop IP
Gateway(config)#
ip default-network 206.143.5.0 next hop IP
2. What command will prevent RIP routing updates from exiting an interface but will sill allow the interface to receive RIP updates?
Router(config-if)#
passive-interface
3. Which two statemnts are true about ip route 172.16.4.0 255.255.255.0 192.168.4.2?
the command establishes a static route
the default admin distance is used (since we didnt give an AD argument)
4. What two destination addresses will be used by HostA to send data to the HTTPS server as shown in the following network?
MAC of RouterA f0/0 interface
IP address of the server
5. Which two statements are true about this output?
RIP: received v1 update from 192.168.40.2 on S0/1
192.168.50.0 in 16 hops (inaccessible)
RIP: sending v1 update to 255.255.255.255 via F0/0 (192.168.30.1)
RIP: build update entries
network 192.168.20.0 metric 1
network 192.168.40.0 metric 1
network 192.168.50.0 metric 16
RIP: sending v1 update to 255.255.255.255 via S0/1 (192.168.40.1)
true:
there are at least two routers exchanging information
192.168.40.2 will be successful
FALSE
there are three interfaces on the router participating in this update
false because we only see two interfaces represented in the output: S0/1(twice) and F0/0
a ping to 192.168.50.1 will be successful
false because that route has a metric of 16; it's unreachable
6. Describe split horizon
will not advertise a route back the the same router it was learned from
7. Which would be true if HostA is trying to communicate to HostB and interface F0/0 of RouterC goes down, as shown in the graphic?
RouterC will send an ICMP 'destination unreachable type' message to inform HostA that HostB is unreachable
8. Which two statements are true regarding classless routing protocols?
VLSM is permitted
RIPv2 supports classless
9. Which two are true regarding distance-vector vs link-state?
Distance vector sends the whole routing table out all active interfaces(even if a router isnt on the other end)at periodic time intervals
Link-state sends updates containing the state of its own links to all routers in the inter-network
10. Which command display RIP routing updates?
debug ip rip
11. What does RIPv2 use to prvent routing loops?
split horizon stops an update from being send on the same interface it was received
holdown timers allow time for a network to become stable in the case of a flapping link
12. A network administrator views the output from the show ip route command. A network that is advertised
by both RIP and EIGRP appears in the routing table flagged an EIGRP route. Why is the RIP route to this network not used in this routing table?
EIGRP has a lower AD.
RIP=120
OSPP=110
IGRP=110
EIGRP=90
13. You type debug ip rip on your router console and see that 172.16.10.0 is being advertised to you with a metric of 16. What does this mean?
it is inaccessible. in RIP if you see a route advertised with a metric of 16, it's inaccessible
14. What metric does RIPv2 use to find the best path to the remote network?
distance aka hop count
15. The Corporate router receives an IP packet with a source IP address of 192.168.214.20 and a destination address of 192.168.22.3. Looking at the output from the Corp router,
what will the router do with this packet?
Corp# show ip route
[cut]
R 192.168.215.0 [120/2] via 192.168.20.2, Serail0/0
R 192.168.115.0 [120/1] via 192.168.20.0, Serial0/0
R 192.168.30.0 [120/1] via 192.168.20.2, Serial0/0
C 192.168.20.0 is directly connected, Serial0/0
C 192.168.214.0 is directly connected, FastEthernet0/0
Since there is no route to that network, the router will discard the packet and send an ICMP destination unreachable message out F0/0 back the the source network
16. If your routing table has a static, a RIP and an EIGRP route to the same network, which route will be used by default?
Static routes have an admin distance of 1 by default. Unless you change it, a static route will always be used over any other
dynamically learned route.
17. You have the following routing table. Which network will NOT be placed in the neighbor routing table?
R 192.168.30.0/24 [120/1] via 192.168.40.1, Serial 0
C 192.168.40.0/24 is directly connected, Serial 0
172.16.0.0/2 is subnetted, 1 subnets
C 172.16.30.0 is directly connected, Loopback0
R 192.168.20.0/24 [120/1] via 192.168.40.1, Serial 0
R 10.0.0.0/8 [120/15] via 192.168.40.1, Serial 0
C 192.168.50.0/24 is directly connected, Ethernet 0
10.0.0.0 cant be placed in neighboring routing table because it is at 15 hops. 16 hops is invalid in RIP
18. Two connected routers are configured only with RIP. What will be the result when a router receives a routing update that contains a
higher-cost path to a network already in it's routing table?
The router will ignore the update because it is higher cost. When a routing update is received, the router first checks the AD and always chooses
the route with the lowest AD.
19.Which is true about route poisoning?
The router sets the metric for a downed link to "infinity".
20. Which is true about RIPv2?
it has all the same timers as RIPv1
------------------------------------------------------------------------------
END CHAPTER 8
54 hours 1-28 thru 2-14-22
original total 143 hours
11.5 hours review 12-23,24,26-22
review total hours 32
book page 428/822
avg 20 min/page (reading and exercises/labs)
Chapter 9 EIGRP and OSPF
pages 427-502, start 2-14-22-M
What is EIGRP?
Note it's not officially on CCNA 200-301 but it is still important to learn
Enhanced IGRP is a classless, enchanced distance vector protocol that uses the concept of an autonomous system to describe
the set of contigous routers that run the same routing protocol and share routing information.
Features:
Support for IP and IPv6 via protocol-dependent modules (seperate routing tables)
Considered classless
Support for summaries and discontiguous networks
Eficient neighbor discovery
communication via RTP- Reliable Transport Protocol
best path selection via Diffusing Updae Algorithm DUAL
Cisco considers EIGRP a "distance-vector" routing protocol
or an "advanced distance-vector" protocol
or a "hybrid" protocol
Configuring EIGRP on our network
------------------------------------------------------------------------------------------------------------------------------------
Corp(config)#
router eigrp ?
<1-65535> Autonomous system number
Corp(config)#
router eigrp 10
R2(config-router)#
network 10.0.0.0
after eigrp on R1- links from Corp to R1 are up
%DUAL-5-NBRCHANGE: IP-EIGRP 10: Neighbor 10.1.3.2 (Serial0/0/1) is up: new adjacency
%DUAL-5-NBRCHANGE: IP-EIGRP 10: Neighbor 10.1.2.2 (Serial0/0/0) is up: new adjacency
after eigrp on R2- link from Corp to R2 is up
%DUAL-5-NBRCHANGE: IP-EIGRP 10: Neighbor 10.1.4.2 (Serial0/1/0) is up: new adjacency
after eigrp on R3- link from Corp to R3 is up
%DUAL-5-NBRCHANGE: IP-EIGRP 10: Neighbor 10.1.5.2 (FastEthernet0/0) is up: new adjacency
------------------------------------------------------------------------------------------------------------------------------------
R1(config)#
router eigrp 10
R1(config-router)#
network 10.0.0.0
after eigrp on R1- link from R1 to Corp is up
%DUAL-5-NBRCHANGE: IP-EIGRP 10: Neighbor 10.1.3.1 (Serial0/0/1) is up: new adjacency
%DUAL-5-NBRCHANGE: IP-EIGRP 10: Neighbor 10.1.2.1 (Serial0/0/0) is up: new adjacency
R1(config-router)#
network 192.168.10.0
R1(config-router)#
network 192.168.20.0
------------------------------------------------------------------------------------------------------------------------------------
R2(config)#
router eigrp 10
R2(config-router)#
network 10.0.0.0
after eigrp on R2- link from R2 to Corp is up
%DUAL-5-NBRCHANGE: IP-EIGRP 10: Neighbor 10.1.4.1 (Serial0/0/0) is up: new adjacency
R1(config-router)#
network 192.168.30.0
R1(config-router)#
network 192.168.40.0
------------------------------------------------------------------------------------------------------------------------------------
R3(config)#
router eigrp 10
R3(config-router)#
network 10.0.0.0
after eigrp on R3- link from R3 to Corp is up
%DUAL-5-NBRCHANGE: IP-EIGRP 10: Neighbor 10.1.5.1 (FastEthernet0/0) is up: new adjacency
R1(config-router)#
network 172.16.0.0
------------------------------------------------------------------------------------------------------------------------------------
Corp#
show ip route
Gateway of last resort is not set
Gateway of last resort is not set
10.0.0.0/8 is variably subnetted, 10 subnets, 2 masks
C 10.1.1.0/24 is directly connected, Vlan1
L 10.1.1.1/32 is directly connected, Vlan1
C 10.1.2.0/24 is directly connected, Serial0/0/0
L 10.1.2.1/32 is directly connected, Serial0/0/0
C 10.1.3.0/24 is directly connected, Serial0/0/1
L 10.1.3.1/32 is directly connected, Serial0/0/1
C 10.1.4.0/24 is directly connected, Serial0/1/0
L 10.1.4.1/32 is directly connected, Serial0/1/0
C 10.1.5.0/24 is directly connected, FastEthernet0/0
L 10.1.5.1/32 is directly connected, FastEthernet0/0
172.16.0.0/16 is variably subnetted, 2 subnets, 2 masks
R 172.16.0.0/16 [120/1] via 10.1.5.2, 00:00:17, FastEthernet0/0
D 172.16.10.0/24 [90/28160] via 10.1.5.2, 00:00:16, FastEthernet0/0
via R3
D 192.168.10.0/24 [90/2172416] via 10.1.2.2, 00:19:13, Serial0/0/0
[90/2172416] via 10.1.3.2, 00:19:13, Serial0/0/1
D 192.168.20.0/24 [90/2172416] via 10.1.3.2, 00:19:05, Serial0/0/1
[90/2172416] via 10.1.2.2, 00:19:05, Serial0/0/0
via R1
D 192.168.30.0/24 [90/2172416] via 10.1.4.2, 00:01:31, Serial0/1/0
D 192.168.40.0/24 [90/2172416] via 10.1.4.2, 00:01:08, Serial0/1/0
via R2
The "D" routes are for DUAL- Diffusing Update Algorithm, indicating they are EIGRP routes.
Note that we have RIP and EIGRP set currently
------------------------------------------------------------------------------------------------------------------------------------
R1#
show ip route
Gateway of last resort is not set
10.0.0.0/8 is variably subnetted, 6 subnets, 2 masks
D 10.0.0.0/8 is a summary, 00:25:28, Null0
D 10.1.1.0/24 [90/27769856] via 10.1.2.1, 00:31:33, Serial0/0/0
[90/27769856] via 10.1.3.1, 00:31:30, Serial0/0/1
via Corp
C 10.1.2.0/24 is directly connected, Serial0/0/0
C 10.1.3.0/24 is directly connected, Serial0/0/1
D 10.1.4.0/24 [90/2681856] via 10.1.2.1, 00:31:33, Serial0/0/0
[90/2681856] via 10.1.3.1, 00:31:30, Serial0/0/1
D 10.1.5.0/24 [90/2172416] via 10.1.2.1, 00:31:33, Serial0/0/0
[90/2172416] via 10.1.3.1, 00:31:30, Serial0/0/1
via Corp
172.16.0.0/16 is variably subnetted, 2 subnets, 2 masks
R 172.16.0.0/16 [120/2] via 10.1.2.1, 00:00:07, Serial0/0/0
[120/2] via 10.1.3.1, 00:00:07, Serial0/0/1
D 172.16.10.0/24 [90/2172416] via 10.1.2.1, 00:06:31, Serial0/0/0
[90/2172416] via 10.1.3.1, 00:06:31, Serial0/0/1
via Corp
C 192.168.10.0/24 is directly connected, FastEthernet0/0
C 192.168.20.0/24 is directly connected, FastEthernet0/1
D 192.168.30.0/24 [90/2684416] via 10.1.3.1, 00:07:46, Serial0/0/1
[90/2684416] via 10.1.2.1, 00:07:46, Serial0/0/0
D 192.168.40.0/24 [90/2684416] via 10.1.2.1, 00:07:23, Serial0/0/0
[90/2684416] via 10.1.3.1, 00:07:23, Serial0/0/1
via Corp
------------------------------------------------------------------------------------------------------------------------------------
R2#
show ip route
Gateway of last resort is not set
10.0.0.0/8 is variably subnetted, 6 subnets, 2 masks
D 10.0.0.0/8 is a summary, 00:13:09, Null0
D 10.1.1.0/24 [90/27769856] via 10.1.4.1, 00:36:53, Serial0/0/0
D 10.1.2.0/24 [90/2681856] via 10.1.4.1, 00:36:53, Serial0/0/0
D 10.1.3.0/24 [90/2681856] via 10.1.4.1, 00:36:53, Serial0/0/0
via Corp
C 10.1.4.0/24 is directly connected, Serial0/0/0
D 10.1.5.0/24 [90/2172416] via 10.1.4.1, 00:36:53, Serial0/0/0
via Corp
172.16.0.0/16 is variably subnetted, 2 subnets, 2 masks
R 172.16.0.0/16 [120/2] via 10.1.4.1, 00:00:23, Serial0/0/0
D 172.16.10.0/24 [90/2172416] via 10.1.4.1, 00:11:54, Serial0/0/0
via Corp
D 192.168.10.0/24 [90/2684416] via 10.1.4.1, 00:30:51, Serial0/0/0
D 192.168.20.0/24 [90/2684416] via 10.1.4.1, 00:30:43, Serial0/0/0
via Corp
C 192.168.30.0/24 is directly connected, FastEthernet0/0
C 192.168.40.0/24 is directly connected, FastEthernet0/1
------------------------------------------------------------------------------------------------------------------------------------
R3#
show ip route
Gateway of last resort is 10.1.5.1 to network 0.0.0.0
10.0.0.0/8 is variably subnetted, 6 subnets, 2 masks
D 10.1.1.0/24 [90/25628160] via 10.1.5.1, 00:37:20, FastEthernet0/0
D 10.1.2.0/24 [90/2172416] via 10.1.5.1, 00:37:15, FastEthernet0/0
D 10.1.3.0/24 [90/2172416] via 10.1.5.1, 00:37:20, FastEthernet0/0
D 10.1.4.0/24 [90/2172416] via 10.1.5.1, 00:37:20, FastEthernet0/0
via Corp
C 10.1.5.0/24 is directly connected, FastEthernet0/0
L 10.1.5.2/32 is directly connected, FastEthernet0/0
172.16.0.0/16 is variably subnetted, 2 subnets, 2 masks
C 172.16.10.0/24 is directly connected, Dot11Radio0/0/0
L 172.16.10.1/32 is directly connected, Dot11Radio0/0/0
D 192.168.10.0/24 [90/2174976] via 10.1.5.1, 00:31:10, FastEthernet0/0
D 192.168.20.0/24 [90/2174976] via 10.1.5.1, 00:31:02, FastEthernet0/0
via Corp and R1
D 192.168.30.0/24 [90/2174976] via 10.1.5.1, 00:13:28, FastEthernet0/0
D 192.168.40.0/24 [90/2174976] via 10.1.5.1, 00:13:05, FastEthernet0/0
via Corp and R2
S* 0.0.0.0/0 [1/0] via 10.1.5.1
------------------------------------------------------------------------------------------------------------------------------------
turn off auto summary on each router
------------------------------------------------------------------------------------------------------------------------------------
Corp(config)#
router eigrp 10
Corp(config-router)#
no auto-summary
------------------------------------------------------------------------------------------------------------------------------------
R1(config)#
router eigrp 10
R1(config-router)#
no auto-summary
------------------------------------------------------------------------------------------------------------------------------------
R2(config)#
router eigrp 10
R2(config-router)#
no auto-summary
------------------------------------------------------------------------------------------------------------------------------------
R3(config)#
router eigrp 10
R3(config-router)#
no auto-summary
------------------------------------------------------------------------------------------------------------------------------------
compare Corp before and after auto summary turned off
------------------------------------------------------------------------------------------------------------------------------------
auto summary on
Corp#
show ip route
Gateway of last resort is not set
10.0.0.0/8 is variably subnetted, 10 subnets, 2 masks
C 10.1.1.0/24 is directly connected, Vlan1
L 10.1.1.1/32 is directly connected, Vlan1
C 10.1.2.0/24 is directly connected, Serial0/0/0
L 10.1.2.1/32 is directly connected, Serial0/0/0
C 10.1.3.0/24 is directly connected, Serial0/0/1
L 10.1.3.1/32 is directly connected, Serial0/0/1
C 10.1.4.0/24 is directly connected, Serial0/1/0
L 10.1.4.1/32 is directly connected, Serial0/1/0
C 10.1.5.0/24 is directly connected, FastEthernet0/0
L 10.1.5.1/32 is directly connected, FastEthernet0/0
172.16.0.0/16 is variably subnetted, 2 subnets, 2 masks
R 172.16.0.0/16 [120/1] via 10.1.5.2, 00:00:17, FastEthernet0/0
D 172.16.10.0/24 [90/28160] via 10.1.5.2, 00:00:16, FastEthernet0/0
via R3
D 192.168.10.0/24 [90/2172416] via 10.1.2.2, 00:19:13, Serial0/0/0
[90/2172416] via 10.1.3.2, 00:19:13, Serial0/0/1
D 192.168.20.0/24 [90/2172416] via 10.1.3.2, 00:19:05, Serial0/0/1
[90/2172416] via 10.1.2.2, 00:19:05, Serial0/0/0
via R1
D 192.168.30.0/24 [90/2172416] via 10.1.4.2, 00:01:31, Serial0/1/0
D 192.168.40.0/24 [90/2172416] via 10.1.4.2, 00:01:08, Serial0/1/0
via R2
auto summary off
Corp#
show ip route
Gateway of last resort is not set
10.0.0.0/8 is variably subnetted, 10 subnets, 2 masks
C 10.1.1.0/24 is directly connected, Vlan1
L 10.1.1.1/32 is directly connected, Vlan1
C 10.1.2.0/24 is directly connected, Serial0/0/0
L 10.1.2.1/32 is directly connected, Serial0/0/0
C 10.1.3.0/24 is directly connected, Serial0/0/1
L 10.1.3.1/32 is directly connected, Serial0/0/1
C 10.1.4.0/24 is directly connected, Serial0/1/0
L 10.1.4.1/32 is directly connected, Serial0/1/0
C 10.1.5.0/24 is directly connected, FastEthernet0/0
L 10.1.5.1/32 is directly connected, FastEthernet0/0
172.16.0.0/16 is variably subnetted, 2 subnets, 2 masks
R 172.16.0.0/16 [120/1] via 10.1.5.2, 00:00:12, FastEthernet0/0
D 172.16.10.0/24 [90/28160] via 10.1.5.2, 00:45:29, FastEthernet0/0
via R3
D 192.168.10.0/24 [90/2172416] via 10.1.2.2, 00:01:08, Serial0/0/0
[90/2172416] via 10.1.3.2, 00:01:08, Serial0/0/1
D 192.168.20.0/24 [90/2172416] via 10.1.2.2, 00:01:08, Serial0/0/0
[90/2172416] via 10.1.3.2, 00:01:08, Serial0/0/1
via R1
D 192.168.30.0/24 [90/2172416] via 10.1.4.2, 00:00:46, Serial0/1/0
D 192.168.40.0/24 [90/2172416] via 10.1.4.2, 00:00:46, Serial0/1/0
via R2
We are still seeing an auto summarized route- 172.16.0.0 coming from R3.
The book discusses enabling EIGRP auto summary on all four routers- nothing is said about disabling it within RIP or turning off RIP.
RIP auto summarizes by default. We cant get rid of this auto summary route while RIP is on.
Moving on...
VERIFYING EIGRP
several commands available to verify and troubleshoot
show ip route
show the entire routing table
show ip route eigrp
show only EIGRP entries in the routing table
show ip eigrp neighbors
show all EIGRP neigbors
show ip eigrp topology
show entries in the EIGRP topology table
show ip protocols
shows routing protocols configuration
debug eigrp packet
shows hello packets sent/received between adjacent routers
debug ip eigrp events
shows EIGRP changes and updates as they occur on your network
lets take a look at the state of our 4 routers. RIP and EIGRP are running on each.
Notice how this command is giving different outputs between the two different IOS versions
IOS 15.1
Corp#
show ip protocols
Routing Protocol is "eigrp 10 "
Outgoing update filter list for all interfaces is not set
Incoming update filter list for all interfaces is not set
Default networks flagged in outgoing updates
Default networks accepted from incoming updates
Redistributing: eigrp 10
EIGRP-IPv4 Protocol for AS(10)
Metric weight K1=1, K2=0, K3=1, K4=0, K5=0
NSF-aware route hold timer is 240
Router-ID: 10.1.1.1
Topology : 0 (base)
Active Timer: 3 min
Distance: internal 90 external 170
Maximum path: 4
Maximum hopcount 100
Maximum metric variance 1
Automatic Summarization: disabled
Automatic address summarization:
Maximum path: 4
Routing for Networks:
10.0.0.0
Routing Information Sources:
Gateway Distance Last Update
10.1.5.2 90 0
10.1.3.2 90 6464
10.1.2.2 90 6795
10.1.4.2 90 7955
Distance: internal 90 external 170
Routing Protocol is "rip"
Sending updates every 30 seconds, next due in 10 seconds
Invalid after 180 seconds, hold down 180, flushed after 240
Outgoing update filter list for all interfaces is not set
Incoming update filter list for all interfaces is not set
Redistributing: rip
Default version control: send version 2, receive 2
Interface Send Recv Triggered RIP Key-chain
Vlan1 2 2
FastEthernet0/0 2 2
Serial0/1/0 2 2
Serial0/0/1 2 2
Serial0/0/0 2 2
Automatic network summarization is in effect
Maximum path: 4
Routing for Networks:
10.0.0.0
Passive Interface(s):
Routing Information Sources:
Gateway Distance Last Update
10.1.5.2 120 00:00:12
10.1.3.2 120 00:00:16
10.1.2.2 120 00:00:16
10.1.4.2 120 00:00:13
Distance: (default is 120)
IOS 12.4
R1#
show ip protocols
Routing Protocol is "eigrp 10 "
Outgoing update filter list for all interfaces is not set
Incoming update filter list for all interfaces is not set
Default networks flagged in outgoing updates
Default networks accepted from incoming updates
EIGRP metric weight K1=1, K2=0, K3=1, K4=0, K5=0
EIGRP maximum hopcount 100
EIGRP maximum metric variance 1
Redistributing: eigrp 10
Automatic network summarization is not in effect
Maximum path: 4
Routing for Networks:
10.0.0.0
192.168.10.0
192.168.20.0
Routing Information Sources:
Gateway Distance Last Update
10.1.3.1 90 6465
10.1.2.1 90 6794
Distance: internal 90 external 170
Routing Protocol is "rip"
Sending updates every 30 seconds, next due in 21 seconds
Invalid after 180 seconds, hold down 180, flushed after 240
Outgoing update filter list for all interfaces is not set
Incoming update filter list for all interfaces is not set
Redistributing: rip
Default version control: send version 2, receive 2
Interface Send Recv Triggered RIP Key-chain
FastEthernet0/0 2 2
FastEthernet0/1 2 2
Serial0/0/0 2 2
Serial0/0/1 2 2
Automatic network summarization is not in effect
Maximum path: 4
Routing for Networks:
10.0.0.0
192.168.10.0
192.168.20.0
Passive Interface(s):
Routing Information Sources:
Gateway Distance Last Update
10.1.3.1 120 00:00:06
10.1.2.1 120 00:00:06
Distance: (default is 120)
IOS 12.4
R2#
show ip protocols
Routing Protocol is "eigrp 10 "
Outgoing update filter list for all interfaces is not set
Incoming update filter list for all interfaces is not set
Default networks flagged in outgoing updates
Default networks accepted from incoming updates
EIGRP metric weight K1=1, K2=0, K3=1, K4=0, K5=0
EIGRP maximum hopcount 100
EIGRP maximum metric variance 1
Redistributing: eigrp 10
Automatic network summarization is not in effect
Maximum path: 4
Routing for Networks:
10.0.0.0
192.168.30.0
192.168.40.0
Routing Information Sources:
Gateway Distance Last Update
10.1.4.1 90 7955
Distance: internal 90 external 170
Routing Protocol is "rip"
Sending updates every 30 seconds, next due in 11 seconds
Invalid after 180 seconds, hold down 180, flushed after 240
Outgoing update filter list for all interfaces is not set
Incoming update filter list for all interfaces is not set
Redistributing: rip
Default version control: send version 2, receive 2
Interface Send Recv Triggered RIP Key-chain
FastEthernet0/0 2 2
FastEthernet0/1 2 2
Serial0/0/0 2 2
Automatic network summarization is in effect
Maximum path: 4
Routing for Networks:
10.0.0.0
192.168.30.0
192.168.40.0
Passive Interface(s):
Routing Information Sources:
Gateway Distance Last Update
10.1.4.1 120 00:00:20
Distance: (default is 120)
IOS 15.1
R3#
show ip protocols
Routing Protocol is "eigrp 10 "
Outgoing update filter list for all interfaces is not set
Incoming update filter list for all interfaces is not set
Default networks flagged in outgoing updates
Default networks accepted from incoming updates
Redistributing: eigrp 10
EIGRP-IPv4 Protocol for AS(10)
Metric weight K1=1, K2=0, K3=1, K4=0, K5=0
NSF-aware route hold timer is 240
Router-ID: 10.1.5.2
Topology : 0 (base)
Active Timer: 3 min
Distance: internal 90 external 170
Maximum path: 4
Maximum hopcount 100
Maximum metric variance 1
Automatic Summarization: disabled
Automatic address summarization:
Maximum path: 4
Routing for Networks:
10.0.0.0
172.16.0.0
Routing Information Sources:
Gateway Distance Last Update
10.1.5.1 90 0
Distance: internal 90 external 170
Routing Protocol is "rip"
Sending updates every 30 seconds, next due in 27 seconds
Invalid after 180 seconds, hold down 180, flushed after 240
Outgoing update filter list for all interfaces is not set
Incoming update filter list for all interfaces is not set
Redistributing: rip
Default version control: send version 2, receive 2
Interface Send Recv Triggered RIP Key-chain
Dot11Radio0/0/0 2 2
FastEthernet0/0 2 2
Automatic network summarization is not in effect
Maximum path: 4
Routing for Networks:
10.0.0.0
172.16.0.0
Passive Interface(s):
Routing Information Sources:
Gateway Distance Last Update
10.1.5.1 120 00:00:02
Distance: (default is 120)
I'm also noticing that we have inconsistent auto-summarization settings- I was having trouble with this earlier. The book discusses
getting rid of the 172.16.0.0 summarized route in the EIGRP settings. I was not able to get rid of it, I think because RIP is still on, and RIP forces auto-summary
Part of the challenge here is that the book is strictly dealing with IOS 12.4
I will now make sure to turn auto summary off for both RIP and EIGRP on each of the four routers.
OK the part I am forgetting is that we are running RIP V2 which does not force auto-summary but runs it optionally, and we must turn it off to avoid auto summarization.
Corp(config)#
router rip
Corp(config-router)#
no auto-summary
Corp(config-router)#
router eigrp 10
Corp(config-router)#
no auto-summary
R1(config)#
router rip
R1(config-router)#
no auto-summary
R1(config-router)#
router eigrp 10
R1(config-router)#
no auto-summary
R1(config)#
router rip
R1(config-router)#
no auto-summary
R1(config-router)#
router eigrp 10
R2(config-router)#
no auto-summary
R3(config)#
router rip
R3(config-router)#
no auto-summary
R3(config-router)#
router eigrp 10
R3(config-router)#
no auto-summary
and lets see how the output looks now. This time I'll do show ip protocols and
show ip route side by side for each router
IOS 15.1
Corp#
show ip protocols
Routing Protocol is "eigrp 10 "
Outgoing update filter list for all interfaces is not set
Incoming update filter list for all interfaces is not set
Default networks flagged in outgoing updates
Default networks accepted from incoming updates
Redistributing: eigrp 10
EIGRP-IPv4 Protocol for AS(10)
Metric weight K1=1, K2=0, K3=1, K4=0, K5=0
NSF-aware route hold timer is 240
Router-ID: 10.1.1.1
Topology : 0 (base)
Active Timer: 3 min
Distance: internal 90 external 170
Maximum path: 4
Maximum hopcount 100
Maximum metric variance 1
Automatic Summarization: disabled
Automatic address summarization:
Maximum path: 4
Routing for Networks:
10.0.0.0
Routing Information Sources:
Gateway Distance Last Update
10.1.5.2 90 0
10.1.3.2 90 6464
10.1.2.2 90 6795
10.1.4.2 90 7955
Distance: internal 90 external 170
Routing Protocol is "rip" doesnt necessarily mean RIPv1
Sending updates every 30 seconds, next due in 3 seconds
Invalid after 180 seconds, hold down 180, flushed after 240
Outgoing update filter list for all interfaces is not set
Incoming update filter list for all interfaces is not set
Redistributing: rip
Default version control: send version 2, receive 2 RIPv2 is specified
Interface Send Recv Triggered RIP Key-chain
Vlan1 2 2
FastEthernet0/0 2 2
Serial0/1/0 2 2
Serial0/0/1 2 2
Serial0/0/0 2 2
Automatic network summarization is not in effect
Maximum path: 4
Routing for Networks:
10.0.0.0
Passive Interface(s):
Routing Information Sources:
Gateway Distance Last Update
10.1.5.2 120 00:00:02
10.1.3.2 120 00:00:21
10.1.2.2 120 00:00:21
10.1.4.2 120 00:00:04
Distance: (default is 120)
IOS 15.1
Corp#
show ip route
Gateway of last resort is not set
10.0.0.0/8 is variably subnetted, 10 subnets, 2 masks
C 10.1.1.0/24 is directly connected, Vlan1
L 10.1.1.1/32 is directly connected, Vlan1
C 10.1.2.0/24 is directly connected, Serial0/0/0
L 10.1.2.1/32 is directly connected, Serial0/0/0
C 10.1.3.0/24 is directly connected, Serial0/0/1
L 10.1.3.1/32 is directly connected, Serial0/0/1
C 10.1.4.0/24 is directly connected, Serial0/1/0
L 10.1.4.1/32 is directly connected, Serial0/1/0
C 10.1.5.0/24 is directly connected, FastEthernet0/0
L 10.1.5.1/32 is directly connected, FastEthernet0/0
172.16.0.0/24 is subnetted, 1 subnets
D 172.16.10.0/24 [90/28160] via 10.1.5.2, 00:57:25, FastEthernet0/0
D 192.168.10.0/24 [90/2172416] via 10.1.3.2, 00:57:20, Serial0/0/1
[90/2172416] via 10.1.2.2, 00:57:20, Serial0/0/0
D 192.168.20.0/24 [90/2172416] via 10.1.3.2, 00:57:20, Serial0/0/1
[90/2172416] via 10.1.2.2, 00:57:20, Serial0/0/0
D 192.168.30.0/24 [90/2172416] via 10.1.4.2, 00:57:19, Serial0/1/0
D 192.168.40.0/24 [90/2172416] via 10.1.4.2, 00:57:19, Serial0/1/0
IOS 12.4
R1#
show ip protocols
Routing Protocol is "eigrp 10 "
Outgoing update filter list for all interfaces is not set
Incoming update filter list for all interfaces is not set
Default networks flagged in outgoing updates
Default networks accepted from incoming updates
EIGRP metric weight K1=1, K2=0, K3=1, K4=0, K5=0
EIGRP maximum hopcount 100
EIGRP maximum metric variance 1
Redistributing: eigrp 10
Automatic network summarization is not in effect
Maximum path: 4
Routing for Networks:
10.0.0.0
192.168.10.0
192.168.20.0
Routing Information Sources:
Gateway Distance Last Update
10.1.3.1 90 6465
10.1.2.1 90 6794
Distance: internal 90 external 170
Routing Protocol is "rip"
Sending updates every 30 seconds, next due in 26 seconds
Invalid after 180 seconds, hold down 180, flushed after 240
Outgoing update filter list for all interfaces is not set
Incoming update filter list for all interfaces is not set
Redistributing: rip
Default version control: send version 2, receive 2
Interface Send Recv Triggered RIP Key-chain
FastEthernet0/0 2 2
FastEthernet0/1 2 2
Serial0/0/0 2 2
Serial0/0/1 2 2
Automatic network summarization is not in effect
Maximum path: 4
Routing for Networks:
10.0.0.0
192.168.10.0
192.168.20.0
Passive Interface(s):
Routing Information Sources:
Gateway Distance Last Update
10.1.3.1 120 00:00:03
10.1.2.1 120 00:00:03
Distance: (default is 120)
IOS 12.4
R1#
show ip route
Gateway of last resort is not set
10.0.0.0/24 is subnetted, 5 subnets
D 10.1.1.0 [90/27769856] via 10.1.3.1, 00:54:47, Serial0/0/1
[90/27769856] via 10.1.2.1, 00:54:47, Serial0/0/0
C 10.1.2.0 is directly connected, Serial0/0/0
C 10.1.3.0 is directly connected, Serial0/0/1
D 10.1.4.0 [90/2681856] via 10.1.3.1, 00:54:47, Serial0/0/1
[90/2681856] via 10.1.2.1, 00:54:47, Serial0/0/0
D 10.1.5.0 [90/2172416] via 10.1.3.1, 00:54:47, Serial0/0/1
[90/2172416] via 10.1.2.1, 00:54:47, Serial0/0/0
172.16.0.0/24 is subnetted, 1 subnets
D 172.16.10.0 [90/2172416] via 10.1.3.1, 00:54:47, Serial0/0/1
[90/2172416] via 10.1.2.1, 00:54:47, Serial0/0/0
C 192.168.10.0/24 is directly connected, FastEthernet0/0
C 192.168.20.0/24 is directly connected, FastEthernet0/1
D 192.168.30.0/24 [90/2684416] via 10.1.3.1, 00:54:46, Serial0/0/1
[90/2684416] via 10.1.2.1, 00:54:46, Serial0/0/0
D 192.168.40.0/24 [90/2684416] via 10.1.3.1, 00:54:46, Serial0/0/1
[90/2684416] via 10.1.2.1, 00:54:46, Serial0/0/0
note that the DUAL routes being advertised from the 10.0.0.0 networks are all specific to the third octet.. that's because we are reading those routes
from their source, aka the router which they are directly connected to, Corp.
and on Corp, those networks were added to the interfaces with a /24 mask.
so even though our EIGRP config doesnt specifically include /24 networks.. we told it to include anything with a 10.x.x.x
Corp is advertising to R1 our /24 network interfaces that have a 10 in the first octet, EXCEPT the two which are directly connected to R1
10.1.1.0
10.1.4.0
10.1.5.0
are assumed to be the subnets based on the info we configured, which was 10.1.4.1/24 on corp, and 10.1.4.2/24 on r2 s0/0/0
nowhere in this configuration, have we entered the 10.1.4.0 network.
EIGRP is figuring it out based on the /24 mask we gave when assiging he IPs to the interfaces
IOS 12.4
R2#
show ip protocols
Routing Protocol is "eigrp 10 "
Outgoing update filter list for all interfaces is not set
Incoming update filter list for all interfaces is not set
Default networks flagged in outgoing updates
Default networks accepted from incoming updates
EIGRP metric weight K1=1, K2=0, K3=1, K4=0, K5=0
EIGRP maximum hopcount 100
EIGRP maximum metric variance 1
Redistributing: eigrp 10
Automatic network summarization is not in effect
Maximum path: 4
Routing for Networks:
10.0.0.0
192.168.30.0
192.168.40.0
Routing Information Sources:
Gateway Distance Last Update
10.1.4.1 90 7955
Distance: internal 90 external 170
Routing Protocol is "rip"
Sending updates every 30 seconds, next due in 18 seconds
Invalid after 180 seconds, hold down 180, flushed after 240
Outgoing update filter list for all interfaces is not set
Incoming update filter list for all interfaces is not set
Redistributing: rip
Default version control: send version 2, receive 2
Interface Send Recv Triggered RIP Key-chain
FastEthernet0/0 2 2
FastEthernet0/1 2 2
Serial0/0/0 2 2
Automatic network summarization is not in effect
Maximum path: 4
Routing for Networks:
10.0.0.0
192.168.30.0
192.168.40.0
Passive Interface(s):
Routing Information Sources:
Gateway Distance Last Update
10.1.4.1 120 00:00:07
Distance: (default is 120)
IOS 12.4
R2#
show ip route
Gateway of last resort is not set
10.0.0.0/24 is subnetted, 5 subnets
D 10.1.1.0 [90/27769856] via 10.1.4.1, 00:59:10, Serial0/0/0
D 10.1.2.0 [90/2681856] via 10.1.4.1, 00:59:10, Serial0/0/0
D 10.1.3.0 [90/2681856] via 10.1.4.1, 00:59:10, Serial0/0/0
C 10.1.4.0 is directly connected, Serial0/0/0
D 10.1.5.0 [90/2172416] via 10.1.4.1, 00:59:10, Serial0/0/0
172.16.0.0/24 is subnetted, 1 subnets
D 172.16.10.0 [90/2172416] via 10.1.4.1, 00:59:10, Serial0/0/0
D 192.168.10.0/24 [90/2684416] via 10.1.4.1, 00:59:10, Serial0/0/0
D 192.168.20.0/24 [90/2684416] via 10.1.4.1, 00:59:10, Serial0/0/0
C 192.168.30.0/24 is directly connected, FastEthernet0/0
C 192.168.40.0/24 is directly connected, FastEthernet0/1
IOS 15.1
R3#
show ip protocols
Routing Protocol is "eigrp 10 "
Outgoing update filter list for all interfaces is not set
Incoming update filter list for all interfaces is not set
Default networks flagged in outgoing updates
Default networks accepted from incoming updates
Redistributing: eigrp 10
EIGRP-IPv4 Protocol for AS(10)
Metric weight K1=1, K2=0, K3=1, K4=0, K5=0
NSF-aware route hold timer is 240
Router-ID: 10.1.5.2
Topology : 0 (base)
Active Timer: 3 min
Distance: internal 90 external 170
Maximum path: 4
Maximum hopcount 100
Maximum metric variance 1
Automatic Summarization: disabled
Automatic address summarization:
Maximum path: 4
Routing for Networks:
10.0.0.0
172.16.0.0
Routing Information Sources:
Gateway Distance Last Update
10.1.5.1 90 0
Distance: internal 90 external 170
Routing Protocol is "rip"
Sending updates every 30 seconds, next due in 15 seconds
Invalid after 180 seconds, hold down 180, flushed after 240
Outgoing update filter list for all interfaces is not set
Incoming update filter list for all interfaces is not set
Redistributing: rip
Default version control: send version 2, receive 2
Interface Send Recv Triggered RIP Key-chain
Dot11Radio0/0/0 2 2
FastEthernet0/0 2 2
Automatic network summarization is not in effect
Maximum path: 4
Routing for Networks:
10.0.0.0
172.16.0.0
Passive Interface(s):
Routing Information Sources:
Gateway Distance Last Update
10.1.5.1 120 00:00:14
Distance: (default is 120)
IOS 15.1
R3#
show ip route
Gateway of last resort is 10.1.5.1 to network 0.0.0.0
10.0.0.0/8 is variably subnetted, 6 subnets, 2 masks
D 10.1.1.0/24 [90/25628160] via 10.1.5.1, 00:59:52, FastEthernet0/0
D 10.1.2.0/24 [90/2172416] via 10.1.5.1, 00:59:47, FastEthernet0/0
D 10.1.3.0/24 [90/2172416] via 10.1.5.1, 00:59:52, FastEthernet0/0
D 10.1.4.0/24 [90/2172416] via 10.1.5.1, 00:59:52, FastEthernet0/0
C 10.1.5.0/24 is directly connected, FastEthernet0/0
L 10.1.5.2/32 is directly connected, FastEthernet0/0
172.16.0.0/16 is variably subnetted, 2 subnets, 2 masks
C 172.16.10.0/24 is directly connected, Dot11Radio0/0/0
L 172.16.10.1/32 is directly connected, Dot11Radio0/0/0
D 192.168.10.0/24 [90/2174976] via 10.1.5.1, 00:59:47, FastEthernet0/0
D 192.168.20.0/24 [90/2174976] via 10.1.5.1, 00:59:47, FastEthernet0/0
D 192.168.30.0/24 [90/2174976] via 10.1.5.1, 00:59:46, FastEthernet0/0
D 192.168.40.0/24 [90/2174976] via 10.1.5.1, 00:59:46, FastEthernet0/0
S* 0.0.0.0/0 [1/0] via 10.1.5.1
Observations:
Since this is a 15.1 router, we always get a "L" local route when
we have a "C" connected route. In R3's case, the 172.16.10.0 network
is directly connected. The interface which connects it, 172.16.10.1,
counts as a "local" route. This is NOT the case on the 12.4 routers.
looking to the left, our protocol output tells us two key facts for both EIGRP and RIP:
Routing for networks:
10.0.0.0
172.16.0.0
R3 is responsible for *sending* data about these two networks to our other EIGRP routers...
"I'm R3 and I can connect you to networks on the R3
router or networks on the Corp router"
Notice how the 192 networks arent listed. R3 isnt connected to a 192 network directly, nor is it connected to a neighbor who is directly connected.
If I, as a client, am sending data to a 192 network from the 172 network, I will start
at R3. Since R3 is receiving routes for the 192 networks via Corp, I will be able to reach a 192 network via Corp.
My connection to corp will happen VIA a "10.0.0.0" route.
R3 is technically only routing for 172 and 10 networks. Beyond that, it could potentially connect to many other different networks. But in terms of the R3 routing table,
all it can offer is a path out to the 172 network or the 10 network
Routing information sources:
10.1.5.1
In this case I can see that R3 is receiving routing data from one interface only,
and that is it's link to Corp. Some of the data we are receiving from Corp actually originates
at other routers, but we cant see that here; the data comes to us from Corp, and that is all we know
EIGRP TERMINOLOGY
FEASIBLE DISTANCE (FD)
the best metric among all paths, including to the next hop neighbor. You will only see the route with the lowest FD appear in the routing table
The FD is calculated by adding the reported distance from the neighbor (AD) plus the metric to that neighbor
ADVERTISED DISTANCE (AD)
the metric of a remote network as reported by a neighbor, listed second in parenthesis in toplogy table
P 192.168.20.0/24, 2 successors, FD is 2172416
via 10.1.3.2 (2172416/28160), Serial0/0/1
feasible / advertised
Neighbor Table
each router keeps state information about adjacent neighbors.. When a new neighbor is learned, the address and interface are recorded.
The neighbor table is stored in RAM.
Sequence numbres are used to match acks with update packets. The last squence number received from a neighbor is recorded so out of order packets
can be detected
Topology Table
acted upon by DUAL Diffusing Update Alogorithm. Contains all destinations advertised by neighboring routers.
For each neighbor, the adversited distance, which comes only from that neighbor's routing table, is recorded
The feasible distance is also recorded.
Feasible Successor
a PATH whose advertised distance is less than the feasible distance of the current succesor, and is considered a backup route.
EIGRP keeps up to 16 feasible successors in the toplogy table.
The one with the best metric (The Successor) is copied and placed into the routing table
Successor
the best route to a remote network, used by EIGRP to forward traffic. It's backed up by a feasible successor, if one is available.
lets demo some more of the commands
VERIFYING EIGRP
several commands available to verify and troubleshoot
show ip route
show the entire routing table
show ip route eigrp
show only EIGRP entries in the routing table
show ip eigrp neighbors
show all EIGRP neigbors
show ip eigrp topology
show entries in the EIGRP topology table
show ip protocols
shows routing protocols configuration
debug eigrp packet
shows hello packets sent/received between adjacent routers
debug ip eigrp events
shows EIGRP changes and updates as they occur on your network
Corp#
show ip eigrp ?
interfaces IP-EIGRP interfaces
neighbors IP-EIGRP neighbors
topology IP-EIGRP Topology Table
traffic IP-EIGRP Traffic Statistics
Corp#
show ip eigrp topology
IP-EIGRP Topology Table for AS 10/ID(10.1.5.1)
Codes: P - Passive, A - Active, U - Update, Q - Query, R - Reply,
r - Reply status
P 10.1.1.0/24, 1 successors, FD is 25625600
via Connected, Vlan1
P 10.1.2.0/24, 1 successors, FD is 2169856
via Connected, Serial0/0/0
P 10.1.3.0/24, 1 successors, FD is 2169856
via Connected, Serial0/0/1
P 10.1.4.0/24, 1 successors, FD is 2169856
via Connected, Serial0/1/0
P 10.1.5.0/24, 1 successors, FD is 28160
via Connected, FastEthernet0/0
P 172.16.10.0/24, 1 successors, FD is 28160
via 10.1.5.2 (28160/25600), FastEthernet0/0
P 192.168.10.0/24, 2 successors, FD is 2172416
via 10.1.3.2 (2172416/28160), Serial0/0/1
via 10.1.2.2 (2172416/28160), Serial0/0/0
P 192.168.20.0/24, 2 successors, FD is 2172416
via 10.1.3.2 (2172416/28160), Serial0/0/1
via 10.1.2.2 (2172416/28160), Serial0/0/0
P 192.168.30.0/24, 1 successors, FD is 2172416
via 10.1.4.2 (2172416/28160), Serial0/1/0
P 192.168.40.0/24, 1 successors, FD is 2172416
via 10.1.4.2 (2172416/28160), Serial0/1/0
the "P" preceding each entry is for PASSIVE
these routes are in a passive state, which is good
if they move to an ACTIVE state, it means the have lost their path in the network and looking for a replacement.
Each entry also shows the FEASIBLE DISTANCE, the next hop address, and the local egress interface
Corp#
show ip eigrp neighbors
IP-EIGRP neighbors for process 10
H Address Interface Hold Uptime SRTT RTO Q Seq
(sec) (ms) Cnt Num
0 10.1.5.2 Fa0/0 14 02:00:05 40 1000 0 19
1 10.1.3.2 Se0/0/1 13 01:59:59 40 1000 0 14
2 10.1.2.2 Se0/0/0 13 01:59:59 40 1000 0 13
3 10.1.4.2 Se0/1/0 12 01:59:57 40 1000 0 15
fields:
H - the order in which the neighbors were discovered
hold - how long the router will wait for a hello packet
uptime - how long the neigborship has been established
SRTT - smooth round trip timer - the time it takes for a round trip from this router, to neighbor, and back.
SRTT is used to determine how long to wait for a MULTICAST reply.
if a reply isnt received in time, the router switches to UNICASTS
RTO - Retransmission Time Out- is the time EIGRP waits before retransmitting a packet from the retransmission queue
Q - indicates wheter there are oustanding messages in the queue
Seq - indicates the sequence number of the last update from that neighbor. This is used to maintain syncrhonization and avoid duplicate
or out-of-sequence processing of messages
Corp#
show ip route eigrp
172.16.0.0/24 is subnetted, 1 subnets
D 172.16.10.0 [90/28160] via 10.1.5.2, 02:08:04, FastEthernet0/0
D 192.168.10.0/24 [90/2172416] via 10.1.3.2, 02:07:59, Serial0/0/1
[90/2172416] via 10.1.2.2, 02:07:59, Serial0/0/0
D 192.168.20.0/24 [90/2172416] via 10.1.3.2, 02:07:59, Serial0/0/1
[90/2172416] via 10.1.2.2, 02:07:59, Serial0/0/0
D 192.168.30.0/24 [90/2172416] via 10.1.4.2, 02:07:58, Serial0/1/0
D 192.168.40.0/24 [90/2172416] via 10.1.4.2, 02:07:58, Serial0/1/0
Corp#
show ip eigrp interfaces
IP-EIGRP interfaces for process 10
Xmit Queue Mean Pacing Time Multicast Pending
Interface Peers Un/Reliable SRTT Un/Reliable Flow Timer Routes
Vlan 0 0/0 1236 0/10 0 0
Fa0/0 1 0/0 1236 0/10 0 0
Se0/1/0 1 0/0 1236 0/10 0 0
Se0/0/1 1 0/0 1236 0/10 0 0
Se0/0/0 1 0/0 1236 0/10 0 0
Corp#
show ip protocols
Routing Protocol is "eigrp 10 "
Outgoing update filter list for all interfaces is not set
Incoming update filter list for all interfaces is not set
Default networks flagged in outgoing updates
Default networks accepted from incoming updates
Redistributing: eigrp 10
EIGRP-IPv4 Protocol for AS(10)
Metric weight K1=1, K2=0, K3=1, K4=0, K5=0 using K1 bandwidth and K2 delay by default
NSF-aware route hold timer is 240
Router-ID: 10.1.1.1
Topology : 0 (base)
Active Timer: 3 min
Distance: internal 90 external 170
Maximum path: 4
Maximum hopcount 100
Maximum metric variance 1
Automatic Summarization: disabled
Automatic address summarization:
Maximum path: 4
Routing for Networks:
10.0.0.0
Routing Information Sources:
Gateway Distance Last Update
10.1.5.2 90 0
10.1.3.2 90 8936
10.1.4.2 90 9511
10.1.2.2 90 9597
Distance: internal 90 external 170
Routing Protocol is "rip"
Sending updates every 30 seconds, next due in 13 seconds
Invalid after 180 seconds, hold down 180, flushed after 240
Outgoing update filter list for all interfaces is not set
Incoming update filter list for all interfaces is not set
Redistributing: rip
Default version control: send version 2, receive 2
Interface Send Recv Triggered RIP Key-chain
Vlan1 2 2
FastEthernet0/0 2 2
Serial0/0/1 2 2
Serial0/1/0 2 2
Serial0/0/0 2 2
Automatic network summarization is not in effect
Maximum path: 4
Routing for Networks:
10.0.0.0
Passive Interface(s):
Routing Information Sources:
Gateway Distance Last Update
10.1.5.2 120 00:00:05
10.1.3.2 120 00:00:12
10.1.2.2 120 00:00:12
10.1.4.2 120 00:00:17
Distance: (default is 120)
corp#
debug eigrp packet
break into two columns for readability
Observations:
There doesnt appear to be a pattern in the order each router is addressed, except that the TO's and FROM"s are grouped together
The TO messages dont show the destination IP, only the egress local interface
The FROM messages do show the remote IP, as well as the local ingress interface
Corp#
EIGRP: Received HELLO on FastEthernet0/0 nbr 10.1.5.2
AS 10, Flags 0x0, Seq 18/0 idbQ 0/0
hello from R3
Corp#
EIGRP: Received HELLO on Serial0/1/0 nbr 10.1.4.2
AS 10, Flags 0x0, Seq 16/0 idbQ 0/0
hello from R2
Corp#
EIGRP: Received HELLO on Serial0/0/0 nbr 10.1.2.2
AS 10, Flags 0x0, Seq 19/0 idbQ 0/0
hello from R1
------------------------------------------------------------
Corp#
EIGRP: Sending HELLO on Serial0/1/0
AS 10, Flags 0x0, Seq 21/0 idbQ 0/0 iidbQ un/rely 0/0
hello to R2
Corp#
EIGRP: Sending HELLO on FastEthernet0/0
AS 10, Flags 0x0, Seq 21/0 idbQ 0/0 iidbQ un/rely 0/0
hello to R3
Corp#
EIGRP: Sending HELLO on Serial0/0/1
AS 10, Flags 0x0, Seq 21/0 idbQ 0/0 iidbQ un/rely 0/0
hello to R1
Corp#
EIGRP: Sending HELLO on Serial0/0/0
AS 10, Flags 0x0, Seq 21/0 idbQ 0/0 iidbQ un/rely 0/0
hello to R1
Corp#
EIGRP: Sending HELLO on Vlan1
AS 10, Flags 0x0, Seq 21/0 idbQ 0/0 iidbQ un/rely 0/0
hello to switch card (not a router....)
------------------------------------------------------------
Corp#
EIGRP: Received HELLO on Serial0/0/1 nbr 10.1.3.2
AS 10, Flags 0x0, Seq 19/0 idbQ 0/0
hello from R1
Corp#
EIGRP: Received HELLO on FastEthernet0/0 nbr 10.1.5.2
AS 10, Flags 0x0, Seq 18/0 idbQ 0/0
hello from R3
Corp#
EIGRP: Received HELLO on Serial0/0/0 nbr 10.1.2.2
AS 10, Flags 0x0, Seq 19/0 idbQ 0/0
hello from R1
Corp#
EIGRP: Received HELLO on Serial0/1/0 nbr 10.1.4.2
AS 10, Flags 0x0, Seq 16/0 idbQ 0/0
hello from R2
------------------------------------------------------------
Corp#
EIGRP: Sending HELLO on Serial0/1/0
AS 10, Flags 0x0, Seq 21/0 idbQ 0/0 iidbQ un/rely 0/0
hello to R2... no neighbor IP?
Corp#
EIGRP: Sending HELLO on Serial0/0/0
AS 10, Flags 0x0, Seq 21/0 idbQ 0/0 iidbQ un/rely 0/0
hello to R1... no neighbor IP?
Corp#
EIGRP: Sending HELLO on FastEthernet0/0
AS 10, Flags 0x0, Seq 21/0 idbQ 0/0 iidbQ un/rely 0/0
hello to R3... no neighbor IP?
Corp#
EIGRP: Sending HELLO on Serial0/0/1
AS 10, Flags 0x0, Seq 21/0 idbQ 0/0 iidbQ un/rely 0/0
hello to R1
Corp#
EIGRP: Sending HELLO on Vlan1
AS 10, Flags 0x0, Seq 21/0 idbQ 0/0 iidbQ un/rely 0/0
hello to switch card (not a router)
------------------------------------------------------------
OUTPUT CONTINUES IN NEXT COLUMN
Corp#
EIGRP: Received HELLO on Serial0/0/1 nbr 10.1.3.2
AS 10, Flags 0x0, Seq 19/0 idbQ 0/0
hello from R1
Corp#
EIGRP: Received HELLO on FastEthernet0/0 nbr 10.1.5.2
AS 10, Flags 0x0, Seq 18/0 idbQ 0/0
hello from R3
Corp#
EIGRP: Received HELLO on Serial0/0/0 nbr 10.1.2.2
AS 10, Flags 0x0, Seq 19/0 idbQ 0/0
hello from R1
Corp#
EIGRP: Received HELLO on Serial0/1/0 nbr 10.1.4.2
AS 10, Flags 0x0, Seq 16/0 idbQ 0/0
hello from R2
------------------------------------------------------------
Corp#
EIGRP: Sending HELLO on Serial0/1/0
AS 10, Flags 0x0, Seq 21/0 idbQ 0/0 iidbQ un/rely 0/0
hello to R2
Corp#
EIGRP: Sending HELLO on Serial0/0/0
AS 10, Flags 0x0, Seq 21/0 idbQ 0/0 iidbQ un/rely 0/0
hello to R1
Corp#
EIGRP: Sending HELLO on Vlan1
AS 10, Flags 0x0, Seq 21/0 idbQ 0/0 iidbQ un/rely 0/0
hello to Corp switchcard
Corp#
EIGRP: Sending HELLO on Serial0/0/1
AS 10, Flags 0x0, Seq 21/0 idbQ 0/0 iidbQ un/rely 0/0
hello to R1
Corp#
EIGRP: Sending HELLO on FastEthernet0/0
AS 10, Flags 0x0, Seq 21/0 idbQ 0/0 iidbQ un/rely 0/0
hello to R3... no neighbor IP?
------------------------------------------------------------
Corp#
EIGRP: Received HELLO on Serial0/0/1 nbr 10.1.3.2
AS 10, Flags 0x0, Seq 19/0 idbQ 0/0
hello from R1
Corp#
EIGRP: Received HELLO on FastEthernet0/0 nbr 10.1.5.2
AS 10, Flags 0x0, Seq 18/0 idbQ 0/0
hello from R3
Corp#
EIGRP: Received HELLO on Serial0/1/0 nbr 10.1.4.2
AS 10, Flags 0x0, Seq 16/0 idbQ 0/0
hello from R2
Corp#
EIGRP: Received HELLO on Serial0/0/0 nbr 10.1.2.2
AS 10, Flags 0x0, Seq 19/0 idbQ 0/0
hello from R1
------------------------------------------------------------
Corp#
EIGRP: Sending HELLO on Serial0/1/0
AS 10, Flags 0x0, Seq 21/0 idbQ 0/0 iidbQ un/rely 0/0
hello to R2
Corp#
EIGRP: Sending HELLO on Vlan1
AS 10, Flags 0x0, Seq 21/0 idbQ 0/0 iidbQ un/rely 0/0
hello to Corp switchcard
EIGRP: Sending HELLO on Serial0/0/0
AS 10, Flags 0x0, Seq 21/0 idbQ 0/0 iidbQ un/rely 0/0
hello to R1
EIGRP: Sending HELLO on Serial0/0/1
AS 10, Flags 0x0, Seq 21/0 idbQ 0/0 iidbQ un/rely 0/0
hello to R1
Corp#
EIGRP: Sending HELLO on FastEthernet0/0
AS 10, Flags 0x0, Seq 21/0 idbQ 0/0 iidbQ un/rely 0/0
hello to R3
------------------------------------------------------------
Now some videos. To reinforce EIGRP concepts, and lead into OSPF
OSPF - OPEN SHORTEST PATH FIRST
Before enabling OSPF, we'll turn off RIP and EIGRP on all four routers.
Device(config)#
no router eigrp 10
Device(config)#
no router rip
The OSPF configs for the local egress ip address
Corp(config)#
router ospf 132
Corp(config)#
network 10.1.0.0 0.0.255.255 area 0
R1(config)#
router ospf 1
R1(config)#
network 10.1.0.0 0.0.255.255 area 0
R1(config)#
network 192.168.0.0 0.0.255.255 area 0
R2(config)#
router ospf 45678
R2(config)#
network 10.0.0.0 0.0.0.255 area 0
R2(config)#
network 192.168.30.1 0.0.0.0 area 0
R2(config)#
network 192.168.40.1 0.0.0.0 area 0
all 32 bits of the mask are specified for the 192 entries;
these are not network id's, they are HOST id's of the specific interfaces, which are EGRESS interfaces on the router we are configuring
R3(config)#
router ospf 1
R2(config)#
network 10.1.5.2 0.0.0.255 area 0
R2(config)#
network 172.16.10.0 0.0.0.255 area 0
Wildcard Masks
these notes are not intended to be a precise explanation of wlidcard masking, but rather a look into my thought process as I am learning the concept.
resources:
traceroute blog examples
routerjockey blog examples
subnetonline wildcard calculator
Ch 9 Exam Essentials
1. Know EIGRP features
classless (like RipV2 and OSPF)
distance vector
supports IP, IPX, appleTalk, IPV6
supports summaries and discontiguous networks
uses the Diffusing Update Algorithm (DUAL) to maintain route information
uses RTP to communicate with other EIGRP routers
uses the concept of an autonomous system to describe the set of contiguous routers that run the same routing protocol and share routing information
considered CLASSLESS- includes the subnet mask in its route updates
sends traditional distance-vector updates containing info about networks plus the cost of reaching them from the perspective of the advertising router
but not strictly distance-vector. Has link-state characteristics: synchronizes routing tables between neighbors at startup and then sends specific updates only when topology changes.
max hop count of 255 (default is 100)
but hop count is NOT a metric, like in RIP. Hop count is how many routers an EIGRP route update can traverse before being discarded. This limits the size of the AS.
2. Know how to configure EIGRP
the router eigrp [as] command turns EIGRP routing on in the router. Unlike RIPv1, EIGRP uses classless routing. BUT you can still configure as classful.
R1(config)#
router eigrp 10
enters router config mode
R1(config-router)#
network 10.0.0.0
on this router, interfaces that fall within 10.0.0.0 will advertise EIGRP info
3. Know how to verify EIGRP operation
Corp#
show ip
protocols
Corp#
show ip
route
Corp#
show ip
route eigrp
Corp#
show ip
eigrp neighbors
Corp#
show ip
eigrp topology
Corp#
show ip
eigrp interfaces
Corp#
show ip
protocols
info about all active routing protocols
Routing Protocol is "eigrp 10 "
Outgoing update filter list for all interfaces is not set
Incoming update filter list for all interfaces is not set
Default networks flagged in outgoing updates
Default networks accepted from incoming updates
Redistributing: eigrp 10
EIGRP-IPv4 Protocol for AS(10)
Metric weight K1=1, K2=0, K3=1, K4=0, K5=0
NSF-aware route hold timer is 240
Router-ID: 10.1.1.1
Topology : 0 (base)
Active Timer: 3 min
Distance: internal 90 external 170
Maximum path: 4
Maximum hopcount 100
Maximum metric variance 1
Automatic Summarization: disabled
Automatic address summarization:
Maximum path: 4
Routing for Networks:
10.0.0.0
Routing Information Sources:
Gateway Distance Last Update
10.1.2.2 90 200105
10.1.3.2 90 200113
10.1.4.2 90 254351
10.1.5.2 90 303742
Distance: internal 90 external 170
Corp#
show ip
protocols
(continued)
Routing Protocol is "rip"
Sending updates every 30 seconds, next due in 6 seconds
Invalid after 180 seconds, hold down 180, flushed after 240
Outgoing update filter list for all interfaces is not set
Incoming update filter list for all interfaces is not set
Redistributing: rip
Default version control: send version 2, receive 2
Interface Send Recv Triggered RIP Key-chain
Vlan1 2 2
FastEthernet0/0 2 2
Serial0/1/0 2 2
Serial0/0/1 2 2
Serial0/0/0 2 2
Automatic network summarization is not in effect
Maximum path: 4
Routing for Networks:
10.0.0.0
Passive Interface(s):
Routing Information Sources:
Gateway Distance Last Update
10.1.5.2 120 00:00:15
10.1.3.2 120 00:00:01
10.1.2.2 120 00:00:01
10.1.4.2 120 00:00:17
Distance: (default is 120)
Corp#
show ip
route
entire routing table
Codes: L - local, C - connected, S - static, R - RIP, M - mobile, B - BGP
D - EIGRP, EX - EIGRP external, O - OSPF, IA - OSPF inter area
N1 - OSPF NSSA external type 1, N2 - OSPF NSSA external type 2
E1 - OSPF external type 1, E2 - OSPF external type 2, E - EGP
i - IS-IS, L1 - IS-IS level-1, L2 - IS-IS level-2, ia - IS-IS inter area
* - candidate default, U - per-user static route, o - ODR
P - periodic downloaded static route
Gateway of last resort is not set
10.0.0.0/8 is variably subnetted, 10 subnets, 2 masks
C 10.1.1.0/24 is directly connected, Vlan1
L 10.1.1.1/32 is directly connected, Vlan1
C 10.1.2.0/24 is directly connected, Serial0/0/0
L 10.1.2.1/32 is directly connected, Serial0/0/0
C 10.1.3.0/24 is directly connected, Serial0/0/1
L 10.1.3.1/32 is directly connected, Serial0/0/1
C 10.1.4.0/24 is directly connected, Serial0/1/0
L 10.1.4.1/32 is directly connected, Serial0/1/0
C 10.1.5.0/24 is directly connected, FastEthernet0/0
L 10.1.5.1/32 is directly connected, FastEthernet0/0
172.16.0.0/16 is variably subnetted, 2 subnets, 2 masks
R 172.16.0.0/16 [120/1] via 10.1.5.2, 00:00:14, FastEthernet0/0
D 172.16.10.0/24 [90/28160] via 10.1.5.2, 00:07:23, FastEthernet0/0
D 192.168.10.0/24 [90/2172416] via 10.1.3.2, 00:09:13, Serial0/0/1
[90/2172416] via 10.1.2.2, 00:09:13, Serial0/0/0
D 192.168.20.0/24 [90/2172416] via 10.1.3.2, 00:09:13, Serial0/0/1
[90/2172416] via 10.1.2.2, 00:09:13, Serial0/0/0
D 192.168.30.0/24 [90/2172416] via 10.1.4.2, 00:08:59, Serial0/1/0
D 192.168.40.0/24 [90/2172416] via 10.1.4.2, 00:08:59, Serial0/1/0
Shows the entire routing table
Corp#
show ip
eigrp toplogy
all nets the Corp router can see, including on the other side of other routers
IP-EIGRP Topology Table for AS 10/ID(10.1.5.1)
Codes: P - Passive, A - Active, U - Update, Q - Query, R - Reply,
r - Reply status
directly connected via local egress interface
P 10.1.1.0/24, 1 successors, FD is 25625600
via Connected, Vlan1
P 10.1.2.0/24, 1 successors, FD is 2169856
via Connected, Serial0/0/0
P 10.1.3.0/24, 1 successors, FD is 2169856
via Connected, Serial0/0/1
P 10.1.4.0/24, 1 successors, FD is 2169856
via Connected, Serial0/1/0
P 10.1.5.0/24, 1 successors, FD is 28160
via Connected, FastEthernet0/0
remotely connected via remote ingress ip address
P 172.16.10.0/24, 1 successors, FD is 28160
via 10.1.5.2 (28160/25600), FastEthernet0/0
P 192.168.10.0/24, 2 successors, FD is 2172416
via 10.1.3.2 (2172416/28160), Serial0/0/1
via 10.1.2.2 (2172416/28160), Serial0/0/0
P 192.168.20.0/24, 2 successors, FD is 2172416
via 10.1.3.2 (2172416/28160), Serial0/0/1
via 10.1.2.2 (2172416/28160), Serial0/0/0
P 192.168.30.0/24, 1 successors, FD is 2172416
via 10.1.4.2 (2172416/28160), Serial0/1/0
P 192.168.40.0/24, 1 successors, FD is 2172416
via 10.1.4.2 (2172416/28160), Serial0/1/0
Corp#
show ip
eigrp interfaces
local interfaces on Corp, with peer data, 5 total, including VLAN1 (0 peers, no router on this network)
IP-EIGRP interfaces for process 10
Xmit Queue Mean Pacing Time Multicast Pending
Interface Peers Un/Reliable SRTT Un/Reliable Flow Timer Routes
Vlan 0 0/0 1236 0/10 0 0
Fa0/0 1 0/0 1236 0/10 0 0
Se0/0/1 1 0/0 1236 0/10 0 0
Se0/1/0 1 0/0 1236 0/10 0 0
Se0/0/0 1 0/0 1236 0/10 0 0
Corp#
show ip
eigrp neighbors
remote interfaces on the 4 neighboring routers
IP-EIGRP neighbors for process 10
H Address Interface Hold Uptime SRTT RTO Q Seq
(sec) (ms) Cnt Num
0 10.1.2.2 Se0/0/0 14 00:54:33 40 1000 0 58
1 10.1.3.2 Se0/0/1 10 00:54:33 40 1000 0 57
2 10.1.4.2 Se0/1/0 14 00:53:38 40 1000 0 51
3 10.1.5.2 Fa0/0 11 00:52:49 40 1000 0 33
4. Compare OSPF and RIPv1
RIPv1 is distance-vector and supports only classful routing. No VLSM
OSPF is link-state and supports VLSM and classless routing
5. Know how OSPF routers become neighboars and/or adjacent
they become neighbors when they see eachother's hello packets.
area id must match, links must be on the same subnet, hello/dead timers must be the same.
OSPF only shares routes with neigbors who have also established adjacencies. NOT ALL NEIGHBORS become adjacent.
When an OSPF router first receives a hello packet, it verifies that the data in some fields matches its own locally configured information.
Should any of the checked data be different, the hello packet is discarded and not processed. The data fields verified are the Area ID,
Authentication, Network Mask (on broadcast networks), Hello Interval, Router Dead Interval, and Options fields. If this information doesn’t match,
then neighborship is stuck in the down stage.
packetpushers.net
6. Be able to configure single-area OSPF
two commands:
router ospf [process id]
network x.x.x.x y.y.y.y area z
7. Be able to verify the operation of OSPF
Corp#
show ip
protocols
Corp#
show ip
route
Corp#
show ip
ospf
Corp#
show ip
ospf database
Corp#
show ip
ospf interface
Corp#
show ip
ospf neighbor
IOS 15.1
Corp#
show ip
protocols
Routing Protocol is "ospf 132"
Outgoing update filter list for all interfaces is not set
Incoming update filter list for all interfaces is not set
Router ID 10.1.5.1
Number of areas in this router is 1. 1 normal 0 stub 0 nssa
Maximum path: 4
Routing for Networks:
10.1.0.0 0.0.255.255 area 0
Routing Information Sources:
Gateway Distance Last Update
10.1.5.1 110 00:08:51
172.16.10.1 110 00:08:51
192.168.20.1 110 00:12:53
192.168.40.1 110 00:09:35
Distance: (default is 110)
IOS 15.1
Corp#
show ip
route
10.0.0.0/8 is variably subnetted, 10 subnets, 2 masks
C 10.1.1.0/24 is directly connected, Vlan1
L 10.1.1.1/32 is directly connected, Vlan1
C 10.1.2.0/24 is directly connected, Serial0/0/0
L 10.1.2.1/32 is directly connected, Serial0/0/0
C 10.1.3.0/24 is directly connected, Serial0/0/1
L 10.1.3.1/32 is directly connected, Serial0/0/1
C 10.1.4.0/24 is directly connected, Serial0/1/0
L 10.1.4.1/32 is directly connected, Serial0/1/0
C 10.1.5.0/24 is directly connected, FastEthernet0/0
L 10.1.5.1/32 is directly connected, FastEthernet0/0
172.16.0.0/24 is subnetted, 1 subnets
O 172.16.10.0/24 [110/10] via 10.1.5.2, 00:09:09, FastEthernet0/0
O 192.168.10.0/24 [110/65] via 10.1.2.2, 00:13:11, Serial0/0/0
O 192.168.20.0/24 [110/65] via 10.1.2.2, 00:13:01, Serial0/0/0
O 192.168.30.0/24 [110/65] via 10.1.4.2, 00:09:54, Serial0/1/0
O 192.168.40.0/24 [110/65] via 10.1.4.2, 00:09:54, Serial0/1/0
IOS 15.1
Corp#
show ip
ospf
Routing Process "ospf 132" with ID 10.1.5.1
Supports only single TOS(TOS0) routes
Supports opaque LSA
SPF schedule delay 5 secs, Hold time between two SPFs 10 secs
Minimum LSA interval 5 secs. Minimum LSA arrival 1 secs
Number of external LSA 0. Checksum Sum 0x000000
Number of opaque AS LSA 0. Checksum Sum 0x000000
Number of DCbitless external and opaque AS LSA 0
Number of DoNotAge external and opaque AS LSA 0
Number of areas in this router is 1. 1 normal 0 stub 0 nssa
External flood list length 0
Area BACKBONE(0)
Number of interfaces in this area is 5
Area has no authentication
SPF algorithm executed 7 times
Area ranges are
Number of LSA 5. Checksum Sum 0x034486
Number of opaque link LSA 0. Checksum Sum 0x000000
Number of DCbitless LSA 0
Number of indication LSA 0
Number of DoNotAge LSA 0
Flood list length 0
IOS 15.1
Corp#
show ip
ospf database
OSPF Router with ID (10.1.5.1) (Process ID 132)
Router Link States (Area 0)
Link ID ADV Router Age Seq# Checksum Link count
192.168.20.1 192.168.20.1 854 0x80000006 0x00ae08 6
192.168.40.1 192.168.40.1 656 0x80000004 0x006bc6 4
10.1.5.1 10.1.5.1 612 0x8000000f 0x00ab77 8
172.16.10.1 172.16.10.1 612 0x80000003 0x00b30d 2
Net Link States (Area 0)
Link ID ADV Router Age Seq# Checksum
10.1.5.1 10.1.5.1 612 0x80000001 0x00cc34
ADV Router aka RID/Router ID, the highest IP address on the router
we are seeing three connected routers + our own router (Corp at 10.1.5.1)
IOS 15.1
Corp#
show ip
ospf interface
Vlan1 is up, line protocol is up
Internet address is 10.1.1.1/24, Area 0
Process ID 132, Router ID 10.1.5.1, Network Type BROADCAST, Cost: 1
Transmit Delay is 1 sec, State DR, Priority 1
Designated Router (ID) 10.1.5.1, Interface address 10.1.1.1
No backup designated router on this network
Timer intervals configured, Hello 10, Dead 40, Wait 40, Retransmit 5
Hello due in 00:00:08
Index 1/1, flood queue length 0
Next 0x0(0)/0x0(0)
Last flood scan length is 1, maximum is 1
Last flood scan time is 0 msec, maximum is 0 msec
Neighbor Count is 0, Adjacent neighbor count is 0
Suppress hello for 0 neighbor(s)
FastEthernet0/0 is up, line protocol is up
Internet address is 10.1.5.1/24, Area 0
Process ID 132, Router ID 10.1.5.1, Network Type BROADCAST, Cost: 1
Transmit Delay is 1 sec, State DR, Priority 1
Designated Router (ID) 10.1.5.1, Interface address 10.1.5.1
Backup Designated Router (ID) 172.16.10.1, Interface address 10.1.5.2
Timer intervals configured, Hello 10, Dead 40, Wait 40, Retransmit 5
Hello due in 00:00:07
Index 2/2, flood queue length 0
Next 0x0(0)/0x0(0)
Last flood scan length is 1, maximum is 1
Last flood scan time is 0 msec, maximum is 0 msec
Neighbor Count is 1, Adjacent neighbor count is 1
Adjacent with neighbor 172.16.10.1 (Backup Designated Router)
Suppress hello for 0 neighbor(s)
Serial0/0/1 is up, line protocol is up
Internet address is 10.1.3.1/24, Area 0
Process ID 132, Router ID 10.1.5.1, Network Type POINT-TO-POINT, Cost: 64
Transmit Delay is 1 sec, State POINT-TO-POINT,
Timer intervals configured, Hello 10, Dead 40, Wait 40, Retransmit 5
Hello due in 00:00:07
Index 3/3, flood queue length 0
Next 0x0(0)/0x0(0)
Last flood scan length is 1, maximum is 1
Last flood scan time is 0 msec, maximum is 0 msec
Neighbor Count is 1 , Adjacent neighbor count is 1
Adjacent with neighbor 192.168.20.1
Suppress hello for 0 neighbor(s)
Serial0/1/0 is up, line protocol is up
Internet address is 10.1.4.1/24, Area 0
Process ID 132, Router ID 10.1.5.1, Network Type POINT-TO-POINT, Cost: 64
Transmit Delay is 1 sec, State POINT-TO-POINT,
Timer intervals configured, Hello 10, Dead 40, Wait 40, Retransmit 5
Hello due in 00:00:07
Index 4/4, flood queue length 0
Next 0x0(0)/0x0(0)
Last flood scan length is 1, maximum is 1
Last flood scan time is 0 msec, maximum is 0 msec
Neighbor Count is 1 , Adjacent neighbor count is 1
Adjacent with neighbor 192.168.40.1
Suppress hello for 0 neighbor(s)
Serial0/0/0 is up, line protocol is up
Internet address is 10.1.2.1/24, Area 0
Process ID 132, Router ID 10.1.5.1, Network Type POINT-TO-POINT, Cost: 64
Transmit Delay is 1 sec, State POINT-TO-POINT,
Timer intervals configured, Hello 10, Dead 40, Wait 40, Retransmit 5
Hello due in 00:00:07
Index 5/5, flood queue length 0
Next 0x0(0)/0x0(0)
Last flood scan length is 1, maximum is 1
Last flood scan time is 0 msec, maximum is 0 msec
Neighbor Count is 1 , Adjacent neighbor count is 1
Adjacent with neighbor 192.168.20.1
Suppress hello for 0 neighbor(s)
IOS 15.1
Corp#
show ip
ospf neighbor
Neighbor ID Pri State Dead Time Address Interface
192.168.20.1 0 FULL/ - 00:00:31 10.1.3.2 Serial0/0/1
192.168.40.1 0 FULL/ - 00:00:33 10.1.4.2 Serial0/1/0
192.168.20.1 0 FULL/ - 00:00:31 10.1.2.2 Serial0/0/0
172.16.10.1 1 FULL/BDR 00:00:32 10.1.5.2 FastEthernet0/0
Flashcards
Chapter 9 Written Lab 9.0
1. What four routed protocols are supported by EIGRP?
IPX, IPv4, IPv6, AppleTalk
2. When is redistribution required for EIGRP?
when there are multiple autonomous systems
redistribution is required when more than one EIGRP session or process is running and they are identified with different ASNs.
redistribution shares toplogy information between EIGRP sessions
3. What command would be used to enable EIGRP with an autonmous system number of 300?
router eigrp 300
4. What command will tell EIGRP that it is connected to network 172.10.0.0?
network 172.10.0.0
5. What type of EIGRP interface will neither send nor receive Hello packets?
passive-interface s0/0
6. Write the command that will enable OSPF process 101 on a router
router ospf 101
7. Write the command that will display details of all OSFP routing processes enabled on a router
show ip ospf
8. Write the command that will display interface-specific OSPF information
show ip ospf interface
9. Write the command that will display all OSPF neighbors
show ip ospf neighbor
10. Write the command that will display all different OSPF route types that are currently known by the router
show ip route ospf
Chapter 9 Hands-On Labs
Build the network and configure interfaces
LabA(config)#
int f0/0
LabA(config-if)#
ip addr 172.16.10.1 255.255.255.0
LabA(config-if)#
no shut
LabB(config)#
int f0/0
LabB(config-if)#
ip addr 172.16.10.2 255.255.255.0
LabB(config-if)#
no shut
LabB(config-if)#
int s0/0/0
LabB(config-if)#
ip addr 172.16.20.1 255.255.255.0
LabB(config-if)#
no shut
LabC(config)#
int f0/0
LabC(config-if)#
ip addr 172.16.30.1 255.255.255.0
LabC(config-if)#
no shut
LabC(config-if)#
int s0/0/0
LabC(config-if)#
ip addr 172.16.20.2 255.255.255.0
LabC(config-if)#
no shut
LabC(config-if)#
int s0/0/1
LabC(config-if)#
ip addr 172.16.40.1 255.255.255.0
LabC(config-if)#
no shut
LabD(config)#
int s0/0/0
LabD(config-if)#
ip addr 172.16.40.2 255.255.255.0
LabD(config-if)#
no shut
LabD(config-if)#
int f0/0
LabD(config-if)#
ip addr 172.16.50.1 255.255.255.0
LabD(config-if)#
no shut
9.1 - Configure and Verfiy EIGRP
configure EIGRP on all 4 routers and observe results
LabA
LabA(config)#
router eigrp 100
LabA(config-router)#
net 172.16.0.0
[no output]
LabA#
show ip eigrp neighbors
IP-EIGRP neighbors for process 100
LabA#
show ip eigrp topology
IP-EIGRP Topology Table for AS 100/ID(172.16.10.1)
Codes: P - Passive, A - Active, U - Update, Q - Query, R - Reply,
r - Reply status
P 172.16.10.0/24, 1 successors, FD is 28160
via Connected, FastEthernet0/0
LabA#
show ip eigrp interfaces
IP-EIGRP interfaces for process 100
Xmit Queue Mean Pacing Time Multicast Pending
Interface Peers Un/Reliable SRTT Un/Reliable Flow Timer Routes
Fa0/0 0 0/0 1236 0/10 0 0
no neighbors at this point since EIGRP is only active on this router. One successor AKA route, which is the connection out of this router.
But note that we have no information about what's on the other side of that link
LabB
LabB(config)#
router eigrp 100
LabB(config-router)#
net 172.16.0.0
%DUAL-5-NBRCHANGE: IP-EIGRP 100:
Neighbor 172.16.10.1 (FastEthernet0/0) is up: new adjacency
LabB#
show ip eigrp neighbors
IP-EIGRP neighbors for process 100
H Address Interface Hold Uptime SRTT RTO Q Seq
(sec) (ms) Cnt Num
0 172.16.10.1 Fa0/0 12 00:00:14 40 1000 0 1
LabB#
show ip eigrp topology
IP-EIGRP Topology Table for AS 100/ID(172.16.20.1)
Codes: P - Passive, A - Active, U - Update, Q - Query, R - Reply,
r - Reply status
P 172.16.10.0/24, 1 successors, FD is 28160
via Connected, FastEthernet0/0
P 172.16.20.0/24, 1 successors, FD is 2169856
via Connected, Serial0/0/0
LabB#
show ip eigrp interfaces
IP-EIGRP interfaces for process 100
Xmit Queue Mean Pacing Time Multicast Pending
Interface Peers Un/Reliable SRTT Un/Reliable Flow Timer Routes
Fa0/0 1 0/0 1236 0/10 0 0
Se0/0/0 0 0/0 1236 0/10 0 0
We can see a neighbor at .1
We now have two paths out of this router. Left to neighbor. Exit at right is available as successor(route), but again we have no info about
what is on the other side, since that router has no EIGRP yet (s0/0/0 has no peers, but is an EIGRP interface)
LabC
LabC(config)#
router eigrp 100
LabC(config-router)#
net 172.16.0.0
%DUAL-5-NBRCHANGE: IP-EIGRP 100:
Neighbor 172.16.20.1 (Serial0/0/0) is up: new adjacency
LabC#
show ip eigrp neighbors
IP-EIGRP neighbors for process 100
H Address Interface Hold Uptime SRTT RTO Q Seq
(sec) (ms) Cnt Num
0 172.16.20.1 Se0/0/0 12 00:00:25 40 1000 0 8
LabC#
show ip eigrp toplogy
IP-EIGRP Topology Table for AS 100/ID(172.16.40.1)
Codes: P - Passive, A - Active, U - Update, Q - Query, R - Reply,
r - Reply status
P 172.16.10.0/24, 1 successors, FD is 2172416
via 172.16.20.1 (2172416/28160), Serial0/0/0
P 172.16.20.0/24, 1 successors, FD is 2169856
via Connected, Serial0/0/0
P 172.16.30.0/24, 1 successors, FD is 28160
via Connected, FastEthernet0/0
P 172.16.40.0/24, 1 successors, FD is 2169856
via Connected, Serial0/0/1
LabC#
show ip eigrp interfaces
IP-EIGRP interfaces for process 100
Xmit Queue Mean Pacing Time Multicast Pending
Interface Peers Un/Reliable SRTT Un/Reliable Flow Timer Routes
Fa0/0 0 0/0 1236 0/10 0 0
Se0/0/0 1 0/0 1236 0/10 0 0
Se0/0/1 0 0/0 1236 0/10 0 0
.1 router B interface is now a neighbor.
LabC topology shows the 3 direct connected networks AND the network on the other side of LabB since LabB is our EIGRP neighbor
3 eigrp interfaces:
Fa0/0 is ours at LabC- no peers bc there is no eigrp router on the other end
s0/0/0 is our interface out left to LabB which is an EIGRP peer
s0/0/1 is our interface out right which does not see an EIGRP peer but does put that net 172.16.40.0 in our topology
LabD
LabD(config)#
router eigrp 100
LabD(config-router)#
net 172.16.0.0
%DUAL-5-NBRCHANGE: IP-EIGRP 100:
Neighbor 172.16.40.1 (Serial0/0/0) is up: new adjacency
LabD#
show ip eigrp neighbors
IP-EIGRP neighbors for process 100
H Address Interface Hold Uptime SRTT RTO Q Seq
(sec) (ms) Cnt Num
0 172.16.40.1 Se0/0/0 11 00:00:14 40 1000 0 6
LabD#
show ip eigrp topology
IP-EIGRP Topology Table for AS 100/ID(172.16.50.1)
Codes: P - Passive, A - Active, U - Update, Q - Query, R - Reply,
r - Reply status
P 172.16.10.0/24, 1 successors, FD is 2684416
via 172.16.40.1 (2684416/2172416), Serial0/0/0
P 172.16.20.0/24, 1 successors, FD is 2681856
via 172.16.40.1 (2681856/2169856), Serial0/0/0
P 172.16.30.0/24, 1 successors, FD is 2172416
via 172.16.40.1 (2172416/28160), Serial0/0/0
P 172.16.40.0/24, 1 successors, FD is 2169856
via Connected, Serial0/0/0
P 172.16.50.0/24, 1 successors, FD is 28160
via Connected, FastEthernet0/0
LabD#
show ip eigrp interfaces
IP-EIGRP interfaces for process 100
Xmit Queue Mean Pacing Time Multicast Pending
Interface Peers Un/Reliable SRTT Un/Reliable Flow Timer Routes
Fa0/0 0 0/0 1236 0/10 0 0
Se0/0/0 1 0/0 1236 0/10 0 0
LabC to our left is now a neighbor at 172.16.40.1
toplogy shows a route out to the right (no router on that end)
a route to the left to LabC .40.0
the .10.0, .20.0, and .30.0 networks via info from LabC
2 eigrp interfaces-
fa0/0 out to the right
s0/0/0 out left to LabC
Time to remove EIGRP from all four routers to prepare for the OSPF lab next,
since EIGRP has a lower AD than OSPF
LabA(config)#
no router eigrp 100
LabB(config)#
no router eigrp 100
LabC(config)#
no router eigrp 100
LabD(config)#
no router eigrp 100
9.2 - Enabling the OSPF Process
9.3 - Configuring OSPF Interfaces
9.4 - Verifying OSPF Operation
LabA
LabA(config)#
router ospf 100
LabA(config-router)#
net 172.16.10.1 0.0.0.0 area 0
[no output]
LabA#
show ip ospf neighbor
[no output]
LabA#
show ip ospf database
OSPF Router with ID (172.16.10.1) (Process ID 100)
Router Link States (Area 0)
Link ID ADV Router Age Seq# Checksum Link count
172.16.10.1 172.16.10.1 44 0x80000001 0x00b24b 1
LabA#
show ip ospf interface
FastEthernet0/0 is up, line protocol is up
Internet address is 172.16.10.1/24, Area 0
Process ID 100, Router ID 172.16.10.1, Network Type BROADCAST, Cost: 1
Transmit Delay is 1 sec, State DR, Priority 1
Designated Router (ID) 172.16.10.1, Interface address 172.16.10.1
No backup designated router on this network
Timer intervals configured, Hello 10, Dead 40, Wait 40, Retransmit 5
Hello due in 00:00:08
Index 1/1, flood queue length 0
Next 0x0(0)/0x0(0)
Last flood scan length is 1, maximum is 1
Last flood scan time is 0 msec, maximum is 0 msec
Neighbor Count is 0, Adjacent neighbor count is 0
Suppress hello for 0 neighbor(s)
we're including this router's interface 172.16.10.1 in our ospf area 0
fa0/0 now registers as an ospf interface
the ospf database includes data about this link only.... LabA is counting itself(10.1) as ADVERTISTING router?
the designated router is .1 LabA
LabB
LabB(config)#
router ospf 101
LabB(config-router)#
net 172.16.10.2 0.0.0.0 area 0
LabB(config-router)#
net 172.16.20.1 0.0.0.0 area 0
01:26:36: %OSPF-5-ADJCHG: Process 101, Nbr 172.16.10.1
on FastEthernet0/0 from LOADING to FULL, Loading Done
LabB#
show ip ospf neighbor
Neighbor ID Pri State Dead Time Address Interface
172.16.10.1 1 FULL/DR 00:00:33 172.16.10.1
LabB#
show ip ospf database
OSPF Router with ID (172.16.20.1) (Process ID 101)
Router Link States (Area 0)
Link ID ADV Router Age Seq# Checksum Link count
172.16.10.1 172.16.10.1 145 0x80000002 0x0067cd 1
172.16.20.1 172.16.20.1 32 0x80000003 0x006e8f 2
Net Link States (Area 0)
Link ID ADV Router Age Seq# Checksum
172.16.10.1 172.16.10.1 145 0x80000001 0x00953d
LabB#
show ip ospf interface
FastEthernet0/0 is up, line protocol is up
Internet address is 172.16.10.2/24, Area 0
Process ID 101, Router ID 172.16.20.1, Network Type BROADCAST, Cost: 1
Transmit Delay is 1 sec, State BDR, Priority 1
Designated Router (ID) 172.16.10.1, Interface address 172.16.10.1
Backup Designated Router (ID) 172.16.20.1, Interface address 172.16.10.2
Timer intervals configured, Hello 10, Dead 40, Wait 40, Retransmit 5
Hello due in 00:00:03
Index 1/1, flood queue length 0
Next 0x0(0)/0x0(0)
Last flood scan length is 1, maximum is 1
Last flood scan time is 0 msec, maximum is 0 msec
Neighbor Count is 1, Adjacent neighbor count is 1
Adjacent with neighbor 172.16.10.1 (Designated Router)
Suppress hello for 0 neighbor(s)
Serial0/0/0 is up, line protocol is up
Internet address is 172.16.20.1/24, Area 0
Process ID 101, Router ID 172.16.20.1, Network Type POINT-TO-POINT, Cost: 64
Transmit Delay is 1 sec, State POINT-TO-POINT,
Timer intervals configured, Hello 10, Dead 40, Wait 40, Retransmit 5
Hello due in 00:00:04
Index 2/2, flood queue length 0
Next 0x0(0)/0x0(0)
Last flood scan length is 1, maximum is 1
Last flood scan time is 0 msec, maximum is 0 msec
Suppress hello for 0 neighbor(s)
We've include the two interfaces on this router in the OSPF area
and can now see Router A's interface 10.1 to the left as a neighbor in the area
the "OSPF Database" now shows two links 20.1(local) and 10.1(neighbor) as 'router link states'.
"ADV Router" means advertising router for the two links. The link address is used as the advertising router.
database shows "Net Link States" category with one entry- 172.16.10.1 which is the address of neighbor router to our left
we have two local OSPF interfaces- f0/0 and s0/0/0
LabC
LabC(config)#
router ospf 102
LabC(config-router)#
net 172.16.20.2 0.0.0.0 area 0
LabC(config-router)#
net 172.16.30.1 0.0.0.0 area 0
LabC(config-router)#
net 172.16.40.1 0.0.0.0 area 0
01:33:54: %OSPF-5-ADJCHG: Process 102, Nbr 172.16.20.1
on Serial0/0/0 from LOADING to FULL, Loading Done
LabC#
show ip ospf neighbor
Neighbor ID Pri State Dead Time Address Interface
172.16.20.1 0 FULL/ - 00:00:30 172.16.20.1 Serial0/0/0
LabC#
show ip ospf database
OSPF Router with ID (172.16.40.1) (Process ID 102)
Router Link States (Area 0)
Link ID ADV Router Age Seq# Checksum Link count
172.16.10.1 172.16.10.1 542 0x80000002 0x0067cd 1
172.16.20.1 172.16.20.1 90 0x80000004 0x00a551 3
172.16.40.1 172.16.40.1 37 0x80000004 0x00e47c 4
Net Link States (Area 0)
Link ID ADV Router Age Seq# Checksum
172.16.10.1 172.16.10.1 542 0x80000001 0x00953d
LabC#
show ip ospf interface
Serial0/0/0 is up, line protocol is up
Internet address is 172.16.20.2/24, Area 0
Process ID 102, Router ID 172.16.40.1, Network Type POINT-TO-POINT, Cost: 64
Transmit Delay is 1 sec, State POINT-TO-POINT,
Timer intervals configured, Hello 10, Dead 40, Wait 40, Retransmit 5
Hello due in 00:00:01
Index 1/1, flood queue length 0
Next 0x0(0)/0x0(0)
Last flood scan length is 1, maximum is 1
Last flood scan time is 0 msec, maximum is 0 msec
Neighbor Count is 1 , Adjacent neighbor count is 1
Adjacent with neighbor 172.16.20.1
Suppress hello for 0 neighbor(s)
FastEthernet0/0 is up, line protocol is up
Internet address is 172.16.30.1/24, Area 0
Process ID 102, Router ID 172.16.40.1, Network Type BROADCAST, Cost: 1
Transmit Delay is 1 sec, State DR, Priority 1
Designated Router (ID) 172.16.40.1, Interface address 172.16.30.1
No backup designated router on this network
Timer intervals configured, Hello 10, Dead 40, Wait 40, Retransmit 5
Hello due in 00:00:02
Index 2/2, flood queue length 0
Next 0x0(0)/0x0(0)
Last flood scan length is 1, maximum is 1
Last flood scan time is 0 msec, maximum is 0 msec
Neighbor Count is 0, Adjacent neighbor count is 0
Suppress hello for 0 neighbor(s)
Serial0/0/1 is up, line protocol is up
Internet address is 172.16.40.1/24, Area 0
Process ID 102, Router ID 172.16.40.1, Network Type POINT-TO-POINT, Cost: 64
Transmit Delay is 1 sec, State POINT-TO-POINT,
Timer intervals configured, Hello 10, Dead 40, Wait 40, Retransmit 5
Hello due in 00:00:08
Index 3/3, flood queue length 0
Next 0x0(0)/0x0(0)
Last flood scan length is 1, maximum is 1
Last flood scan time is 0 msec, maximum is 0 msec
Suppress hello for 0 neighbor(s)
we include the three nets conneted to labC in the area.. 20.0, 30.0, and 40.0
link to our left, 20.1 is visible as "Neighbor"
OSPF Database-
Router Link States are
10.1(Router A)
20.1(Router B)
40.1(Router C)(This router)
Net Link States
10.1(Router A)... why does only Router A show here?
Reference- router link state vs net link state
Router Link States are type 1 LSAs. It lists all the routers in the area and the number of interfaces. 40.1 has 4 interfaces
Net Link States are the multi-access networks (Type 2 LSAs). The ADV (advertising router) is the DR.
LabD
LabD(config)#
router ospf 103
LabD(config-router)#
net 172.16.40.2 0.0.0.0 area 0
LabD(config-router)#
net 172.16.50.1 0.0.0.0 area 0
01:37:11: %OSPF-5-ADJCHG: Process 103, Nbr 172.16.40.1
on Serial0/0/0 from LOADING to FULL, Loading Done
LabD#
show ip ospf neighbor
Neighbor ID Pri State Dead Time Address Interface
172.16.40.1 0 FULL/ - 00:00:32 172.16.40.1 Serial0/0/0
LabD#
show ip ospf database
OSPF Router with ID (172.16.50.1) (Process ID 103)
Router Link States (Area 0)
Link ID ADV Router Age Seq# Checksum Link count
172.16.10.1 172.16.10.1 785 0x80000002 0x0067cd 1
172.16.20.1 172.16.20.1 333 0x80000004 0x00a551 3
172.16.40.1 172.16.40.1 111 0x80000005 0x00013b 5
172.16.50.1 172.16.50.1 53 0x80000003 0x001023 3
Net Link States (Area 0)
Link ID ADV Router Age Seq# Checksum
172.16.10.1 172.16.10.1 785 0x80000001 0x00953d
LabD#
show ip ospf interface
Serial0/0/0 is up, line protocol is up
Internet address is 172.16.40.2/24, Area 0
Process ID 103, Router ID 172.16.50.1, Network Type POINT-TO-POINT, Cost: 64
Transmit Delay is 1 sec, State POINT-TO-POINT,
Timer intervals configured, Hello 10, Dead 40, Wait 40, Retransmit 5
Hello due in 00:00:01
Index 1/1, flood queue length 0
Next 0x0(0)/0x0(0)
Last flood scan length is 1, maximum is 1
Last flood scan time is 0 msec, maximum is 0 msec
Neighbor Count is 1 , Adjacent neighbor count is 1
Adjacent with neighbor 172.16.40.1
Suppress hello for 0 neighbor(s)
FastEthernet0/0 is up, line protocol is up
Internet address is 172.16.50.1/24, Area 0
Process ID 103, Router ID 172.16.50.1, Network Type BROADCAST, Cost: 1
Transmit Delay is 1 sec, State WAITING, Priority 1
No designated router on this network
No backup designated router on this network
Timer intervals configured, Hello 10, Dead 40, Wait 40, Retransmit 5
Hello due in 00:00:04
Index 2/2, flood queue length 0
Next 0x0(0)/0x0(0)
Last flood scan length is 1, maximum is 1
Last flood scan time is 0 msec, maximum is 0 msec
Neighbor Count is 0, Adjacent neighbor count is 0
Suppress hello for 0 neighbor(s)
observations
the OSPF databases now match across all 4 routers.
NOTE that this is a database of routers, identified by
router ID. It is not a topology that lists routers AND routes,
like in the "equivalent" eigrp command.show eigrp topology
----------------------------------------------------------------------------------
PAUSE- a tale of a misconfigured network
After a 9 month hiatus, I am reviewing this book and have made it back to Chapter 9. I'm studing this webpage, working thorough the OSPF configurations
described above, and I get stuck on the concept of "link count" under "Router Link States" found in the output of show ip ospf database
The structure of the notes above is helpful, because I was tracking the state of each router BEFORE i made changes to the subsquent router. But just to be sure,
today I decided to recreate the topology, then configure each router one at a time, noting the results as I went.
And I ran into some problems.
Here is the original topology:
And today's recreated toplogy:
After replicating the toplogy and programming the IP addresses on each router, I started on configurations, just like before:
LabA
LabA(config)#
router ospf 100
LabA(config-router)#
net 172.16.10.1 0.0.0.0 area 0
[no output]
LabA#
show ip ospf neighbor
[no output]
LabA#
show ip ospf database
OSPF Router with ID (172.16.10.1) (Process ID 100)
Router Link States (Area 0)
Link ID ADV Router Age Seq# Checksum Link count
172.16.10.1 172.16.10.1 44 0x80000001 0x00b24b 1
LabA#
show ip ospf interface
FastEthernet0/0 is up, line protocol is up
Internet address is 172.16.10.1/24, Area 0
Process ID 100, Router ID 172.16.10.1, Network Type BROADCAST, Cost: 1
Transmit Delay is 1 sec, State DR, Priority 1
Designated Router (ID) 172.16.10.1, Interface address 172.16.10.1
No backup designated router on this network
Timer intervals configured, Hello 10, Dead 40, Wait 40, Retransmit 5
Hello due in 00:00:08
Index 1/1, flood queue length 0
Next 0x0(0)/0x0(0)
Last flood scan length is 1, maximum is 1
Last flood scan time is 0 msec, maximum is 0 msec
Neighbor Count is 0, Adjacent neighbor count is 0
Suppress hello for 0 neighbor(s)
good so far.... On to LabB router
LabB
LabB(config)#
router ospf 101
LabB(config-router)#
net 172.16.10.2 0.0.0.0 area 0
LabB(config-router)#
net 172.16.20.1 0.0.0.0 area 0
01:26:36: %OSPF-5-ADJCHG: Process 101, Nbr 172.16.10.1
on FastEthernet0/0 from LOADING to FULL, Loading Done
LabB#
show ip ospf neighbor
Neighbor ID Pri State Dead Time Address Interface
172.16.10.1 1 FULL/DR 00:00:33 172.16.10.1
LabB#
show ip ospf database
OSPF Router with ID (172.16.20.1) (Process ID 101)
Router Link States (Area 0)
Link ID ADV Router Age Seq# Checksum Link count
172.16.10.1 172.16.10.1 145 0x80000002 0x0067cd 1
172.16.20.1 172.16.20.1 32 0x80000003 0x006e8f 2
Net Link States (Area 0)
Link ID ADV Router Age Seq# Checksum
172.16.10.1 172.16.10.1 145 0x80000001 0x00953d
LabB#
show ip ospf interface
FastEthernet0/0 is up, line protocol is up
Internet address is 172.16.10.2/24, Area 0
Process ID 101, Router ID 172.16.20.1, Network Type BROADCAST, Cost: 1
Transmit Delay is 1 sec, State BDR, Priority 1
Designated Router (ID) 172.16.10.1, Interface address 172.16.10.1
Backup Designated Router (ID) 172.16.20.1, Interface address 172.16.10.2
Timer intervals configured, Hello 10, Dead 40, Wait 40, Retransmit 5
Hello due in 00:00:03
Index 1/1, flood queue length 0
Next 0x0(0)/0x0(0)
Last flood scan length is 1, maximum is 1
Last flood scan time is 0 msec, maximum is 0 msec
Neighbor Count is 1, Adjacent neighbor count is 1
Adjacent with neighbor 172.16.10.1 (Designated Router)
Suppress hello for 0 neighbor(s)
Serial0/0/0 is up, line protocol is up
Internet address is 172.16.20.1/24, Area 0
Process ID 101, Router ID 172.16.20.1, Network Type POINT-TO-POINT, Cost: 64
Transmit Delay is 1 sec, State POINT-TO-POINT,
Timer intervals configured, Hello 10, Dead 40, Wait 40, Retransmit 5
Hello due in 00:00:04
Index 2/2, flood queue length 0
Next 0x0(0)/0x0(0)
Last flood scan length is 1, maximum is 1
Last flood scan time is 0 msec, maximum is 0 msec
Suppress hello for 0 neighbor(s)
still looks good; same as before.... On to LabC router
LabC
LabC(config)#
router ospf 102
LabC(config-router)#
net 172.16.20.2 0.0.0.0 area 0
LabC(config-router)#
net 172.16.30.1 0.0.0.0 area 0
LabC(config-router)#
net 172.16.40.1 0.0.0.0 area 0
01:33:54: %OSPF-5-ADJCHG: Process 102, Nbr 172.16.20.1
on Serial0/0/0 from LOADING to FULL, Loading Done
LabC#
show ip ospf neighbor
[no output]
And here is where I ran into trouble. The show ip ospf neighbor command returns nothing. How can
that be?
After awhile I realized it is due to a misconfiguration in the topology.
For Lab C, I programmed the interfaces as follows:
LabC(config)#
int f0/0
LabC(config-if)#
ip addr 172.16.30.1 255.255.255.0
LabC(config-if)#
no shut
LabC(config-if)#
int s0/0/0
LabC(config-if)#
ip addr 172.16.20.2 255.255.255.0
LabC(config-if)#
no shut
LabC(config-if)#
int s0/0/1
LabC(config-if)#
ip addr 172.16.40.1 255.255.255.0
LabC(config-if)#
no shut
and again here is the topology for that router:
but here is what it SHOULD HAVE looked like (as it did the first time I built it)
S0/0/0 and S0/0/1 are swapped. When I gave the IP 172.16.20.2 to s/0/0/0, thinking that was the interface on the left side
which faces Lab B, I was actually giving 172.16.20.2 to the right side, facing LabC (which has no OSPF configs yet.)
Since the left side got got the IP intended for the right side which was 172.16.40.1
the inverse also occured-
the right side got the IP intended for the left which was 172.16.20.2
LabC left side should have been
s0/0/0 with 20.2
and LabC right side should have been
s0/0/1 with 40.1
The correct IPs were mapped to the correct interfaces. But the mistake happened before I even programmed them.
When I made the connections from LabB to LabC and from LabD to LabC, I plugged then into the wrong ports.
Interestingly.. not only is this causing OSPF to not see B as a neighbor from C.. but B and C cannot ping eachother either.
@B the config is 172.16.20.1/24 @ S0/0/0
@C the config is 172.16.40.1/24 @ S/0/0/1
meaning they are not even on the same network! But the system is not throwing any errors or bringing it to my attention.
It just fails to connect.
To correct the issue, I simply deleted those two links and re-created them. Worth noting, I used the auto select cable here,
which does not ask which interface you want to use when attaching. Earlier I must have plugged the right side first, and
auto select plugged into 0/0/0.
This time I plugged into left side first.
Now LabC OSPF data is reading out correctly...
LabC
LabC(config)#
router ospf 102
LabC(config-router)#
net 172.16.20.2 0.0.0.0 area 0
LabC(config-router)#
net 172.16.30.1 0.0.0.0 area 0
LabC(config-router)#
net 172.16.40.1 0.0.0.0 area 0
01:33:54: %OSPF-5-ADJCHG: Process 102, Nbr 172.16.20.1
on Serial0/0/0 from LOADING to FULL, Loading Done
LabC#
show ip ospf neighbor
Neighbor ID Pri State Dead Time Address Interface
172.16.20.1 0 FULL/ - 00:00:30 172.16.20.1 Serial0/0/0
LabC#
show ip ospf database
OSPF Router with ID (172.16.40.1) (Process ID 102)
Router Link States (Area 0)
Link ID ADV Router Age Seq# Checksum Link count
172.16.10.1 172.16.10.1 542 0x80000002 0x0067cd 1
172.16.20.1 172.16.20.1 90 0x80000004 0x00a551 3
172.16.40.1 172.16.40.1 37 0x80000004 0x00e47c 4
Net Link States (Area 0)
Link ID ADV Router Age Seq# Checksum
172.16.10.1 172.16.10.1 542 0x80000001 0x00953d
LabC#
show ip ospf interface
Serial0/0/0 is up, line protocol is up
Internet address is 172.16.20.2/24, Area 0
Process ID 102, Router ID 172.16.40.1, Network Type POINT-TO-POINT, Cost: 64
Transmit Delay is 1 sec, State POINT-TO-POINT,
Timer intervals configured, Hello 10, Dead 40, Wait 40, Retransmit 5
Hello due in 00:00:01
Index 1/1, flood queue length 0
Next 0x0(0)/0x0(0)
Last flood scan length is 1, maximum is 1
Last flood scan time is 0 msec, maximum is 0 msec
Neighbor Count is 1 , Adjacent neighbor count is 1
Adjacent with neighbor 172.16.20.1
Suppress hello for 0 neighbor(s)
FastEthernet0/0 is up, line protocol is up
Internet address is 172.16.30.1/24, Area 0
Process ID 102, Router ID 172.16.40.1, Network Type BROADCAST, Cost: 1
Transmit Delay is 1 sec, State DR, Priority 1
Designated Router (ID) 172.16.40.1, Interface address 172.16.30.1
No backup designated router on this network
Timer intervals configured, Hello 10, Dead 40, Wait 40, Retransmit 5
Hello due in 00:00:02
Index 2/2, flood queue length 0
Next 0x0(0)/0x0(0)
Last flood scan length is 1, maximum is 1
Last flood scan time is 0 msec, maximum is 0 msec
Neighbor Count is 0, Adjacent neighbor count is 0
Suppress hello for 0 neighbor(s)
Serial0/0/1 is up, line protocol is up
Internet address is 172.16.40.1/24, Area 0
Process ID 102, Router ID 172.16.40.1, Network Type POINT-TO-POINT, Cost: 64
Transmit Delay is 1 sec, State POINT-TO-POINT,
Timer intervals configured, Hello 10, Dead 40, Wait 40, Retransmit 5
Hello due in 00:00:08
Index 3/3, flood queue length 0
Next 0x0(0)/0x0(0)
Last flood scan length is 1, maximum is 1
Last flood scan time is 0 msec, maximum is 0 msec
Suppress hello for 0 neighbor(s)
Which brings me to the original reason I re-created this topology... I was confused about the LINK COUNTS
here:
OSPF Router with ID (172.16.40.1) (Process ID 102)
Router Link States (Area 0)
Link ID ADV Router Age Seq# Checksum Link count
172.16.10.1 172.16.10.1 542 0x80000002 0x0067cd 1
172.16.20.1 172.16.20.1 90 0x80000004 0x00a551 3
172.16.40.1 172.16.40.1 37 0x80000004 0x00e47c 4
Net Link States (Area 0)
Link ID ADV Router Age Seq# Checksum
172.16.10.1 172.16.10.1 542 0x80000001 0x00953d
The steps of recreating the lab were helpful, but this link answered the question:
Here is the output of each router's command show ip ospf interface as they are
set up one at a time.
LabA - No OSPF at B, C, or D yet
show ip ospf database
OSPF Router with ID (172.16.10.1) (Process ID 100)
Router Link States (Area 0)
Link ID ADV Router Age Seq# Checksum Link count
172.16.10.1 172.16.10.1 44 0x80000001 0x00b24b 1
LabB - No OSPF at C or D yet
show ip ospf database
OSPF Router with ID (172.16.20.1) (Process ID 101)
Router Link States (Area 0)
Link ID ADV Router Age Seq# Checksum Link count
172.16.10.1 172.16.10.1 145 0x80000002 0x0067cd 1
172.16.20.1 172.16.20.1 32 0x80000003 0x006e8f 2
Net Link States (Area 0)
Link ID ADV Router Age Seq# Checksum
172.16.10.1 172.16.10.1 145 0x80000001 0x00953d
the 20.2 interface on this router has 2 ospf links.
The left-facing out to RA, a crossover cable
The right-facing out to RC, a serial cable.
If the solution I found is correct, why is this serial link not being counted twice? The solution (I think)
is revealed after the configuration of the next router...
LabC - No OSPF at D yet
show ip ospf database
OSPF Router with ID (172.16.40.1) (Process ID 102)
Router Link States (Area 0)
Link ID ADV Router Age Seq# Checksum Link count
172.16.10.1 172.16.10.1 542 0x80000002 0x0067cd 1
172.16.20.1 172.16.20.1 90 0x80000004 0x00a551 3
172.16.40.1 172.16.40.1 37 0x80000004 0x00e47c 4
Net Link States (Area 0)
Link ID ADV Router Age Seq# Checksum
172.16.10.1 172.16.10.1 542 0x80000001 0x00953d
NOW we can see that the 20.1 link, which is the right-facing interface on LabB.. aka the router ID..
has THREE OSPF links.
Nothing changed on the left side of B. But on the right side, we now have an active OSPF router at the
other end of the link. This leads me to believe that the forum post was correct that 'serial links are counted twice',
but, more specifically, BOTH ENDS of the serial(PPP) link are counted... IF there is an OSPF router on each end.
This is backed up by the fact that LabC, OSPF id 40.1, has four OSPF links. The top-facing link to the 30
network DOES count.. even though it has no OSPF router on the other end. It counts because it's not a serial link.
The requirement of having an OSPF router on the other end for an interface to count here, only applies
to serial links. And pertains to BOTH ends of the link being counted.
In LabC's case, we have one serial at left, being counted twice. One ethernet at top, being counted once. And
one serial at right only being counted once because LabD is not active with OSPF yet.
If this is correct, then we should see Lab C's 40.1 count go to 5 after LabD is set for OSPF....
LabD - all 4 routers have OSPF
show ip ospf database
OSPF Router with ID (172.16.50.1) (Process ID 103)
Router Link States (Area 0)
Link ID ADV Router Age Seq# Checksum Link count
172.16.10.1 172.16.10.1 785 0x80000002 0x0067cd 1
172.16.20.1 172.16.20.1 333 0x80000004 0x00a551 3
172.16.40.1 172.16.40.1 111 0x80000005 0x00013b 5
172.16.50.1 172.16.50.1 53 0x80000003 0x001023 3
Net Link States (Area 0)
Link ID ADV Router Age Seq# Checksum
172.16.10.1 172.16.10.1 785 0x80000001 0x00953d
and back to LabC.....
show ip ospf database
OSPF Router with ID (172.16.40.1) (Process ID 102)
Router Link States (Area 0)
Link ID ADV Router Age Seq# Checksum Link count
172.16.10.1 172.16.10.1 1174 0x80000002 0x0067cd 1
172.16.20.1 172.16.20.1 722 0x80000004 0x00a551 3
172.16.40.1 172.16.40.1 500 0x80000005 0x00013b 5
172.16.50.1 172.16.50.1 441 0x80000003 0x001023 3
Net Link States (Area 0)
Link ID ADV Router Age Seq# Checksum
172.16.10.1 172.16.10.1 1174 0x80000001 0x00953d
Looks good! The link count for each router makes sense if you count the serial interfaces twice (one for each end).
the OSPF databases now match across all 4 routers.
NOTE that this is a database of routers, identified by
router ID. It is not a topology that lists routers AND routes, like in
the "equivalent" eigrp command show eigrp topology
Note that the .30 network is NOT represented here.
LabA#
show ip ospf database
OSPF Router with ID (172.16.10.1) (Process ID 100)
Router Link States (Area 0)
Link ID ADV Router Age Seq# Checksum Link count
172.16.10.1 172.16.10.1 1138 0x80000002 0x0067cd 1
172.16.20.1 172.16.20.1 686 0x80000004 0x00a551 3
172.16.40.1 172.16.40.1 463 0x80000005 0x00013b 5
172.16.50.1 172.16.50.1 404 0x80000003 0x001023 3
Net Link States (Area 0)
Link ID ADV Router Age Seq# Checksum
172.16.10.1 172.16.10.1 1138 0x80000001 0x00953d
LabB#
show ip ospf database
OSPF Router with ID (172.16.20.1) (Process ID 101)
Router Link States (Area 0)
Link ID ADV Router Age Seq# Checksum Link count
172.16.10.1 172.16.10.1 1151 0x80000002 0x0067cd 1
172.16.20.1 172.16.20.1 699 0x80000004 0x00a551 3
172.16.40.1 172.16.40.1 476 0x80000005 0x00013b 5
172.16.50.1 172.16.50.1 417 0x80000003 0x001023 3
Net Link States (Area 0)
Link ID ADV Router Age Seq# Checksum
172.16.10.1 172.16.10.1 1151 0x80000001 0x00953d
LabC#
show ip ospf database
OSPF Router with ID (172.16.40.1) (Process ID 102)
Router Link States (Area 0)
Link ID ADV Router Age Seq# Checksum Link count
172.16.10.1 172.16.10.1 1174 0x80000002 0x0067cd 1
172.16.20.1 172.16.20.1 722 0x80000004 0x00a551 3
172.16.40.1 172.16.40.1 500 0x80000005 0x00013b 5
172.16.50.1 172.16.50.1 441 0x80000003 0x001023 3
Net Link States (Area 0)
Link ID ADV Router Age Seq# Checksum
172.16.10.1 172.16.10.1 1174 0x80000001 0x00953d
LabD#
show ip ospf database
OSPF Router with ID (172.16.50.1) (Process ID 103)
Router Link States (Area 0)
Link ID ADV Router Age Seq# Checksum Link count
172.16.10.1 172.16.10.1 785 0x80000002 0x0067cd 1
172.16.20.1 172.16.20.1 333 0x80000004 0x00a551 3
172.16.40.1 172.16.40.1 111 0x80000005 0x00013b 5
172.16.50.1 172.16.50.1 53 0x80000003 0x001023 3
Net Link States (Area 0)
Link ID ADV Router Age Seq# Checksum
172.16.10.1 172.16.10.1 785 0x80000001 0x00953d
Below is our routing tables with OSPF data. We do see the .30 network here.
Everyone can reach it:
LabA via LabB's 10.2
LabB via LabC's 20.2
LabC via direct connection
LabD via LabC's 40.1
LabA#
show ip route
172.16.0.0/16 is variably subnetted, 6 subnets, 2 masks
C 172.16.10.0/24 is directly connected, FastEthernet0/0
L 172.16.10.1/32 is directly connected, FastEthernet0/0
O 172.16.20.0/24 [110/65] via 172.16.10.2, 00:28:03, FastEthernet0/0
O 172.16.30.0/24 [110/66] via 172.16.10.2, 00:21:35, FastEthernet0/0
O 172.16.40.0/24 [110/129] via 172.16.10.2, 00:21:25, FastEthernet0/0
O 172.16.50.0/24 [110/130] via 172.16.10.2, 00:17:40, FastEthernet0/0
LabB#
show ip route
172.16.0.0/16 is variably subnetted, 7 subnets, 2 masks
C 172.16.10.0/24 is directly connected, FastEthernet0/0
L 172.16.10.2/32 is directly connected, FastEthernet0/0
C 172.16.20.0/24 is directly connected, Serial0/0/0
L 172.16.20.1/32 is directly connected, Serial0/0/0
O 172.16.30.0/24 [110/65] via 172.16.20.2, 00:27:04, Serial0/0/0
O 172.16.40.0/24 [110/128] via 172.16.20.2, 00:26:54, Serial0/0/0
O 172.16.50.0/24 [110/129] via 172.16.20.2, 00:23:09, Serial0/0/0
LabC#
show ip route
172.16.0.0/16 is variably subnetted, 8 subnets, 2 masks
O 172.16.10.0/24 [110/65] via 172.16.20.1, 00:27:52, Serial0/0/0
C 172.16.20.0/24 is directly connected, Serial0/0/0
L 172.16.20.2/32 is directly connected, Serial0/0/0
C 172.16.30.0/24 is directly connected, FastEthernet0/0
L 172.16.30.1/32 is directly connected, FastEthernet0/0
C 172.16.40.0/24 is directly connected, Serial0/0/1
L 172.16.40.1/32 is directly connected, Serial0/0/1
O 172.16.50.0/24 [110/65] via 172.16.40.2, 00:23:36, Serial0/0/1
LabD#
show ip route
172.16.0.0/16 is variably subnetted, 7 subnets, 2 masks
O 172.16.10.0/24 [110/129] via 172.16.40.1, 00:25:20, Serial0/0/0
O 172.16.20.0/24 [110/128] via 172.16.40.1, 00:25:20, Serial0/0/0
O 172.16.30.0/24 [110/65] via 172.16.40.1, 00:25:20, Serial0/0/0
C 172.16.40.0/24 is directly connected, Serial0/0/0
L 172.16.40.2/32 is directly connected, Serial0/0/0
C 172.16.50.0/24 is directly connected, FastEthernet0/0
L 172.16.50.1/32 is directly connected, FastEthernet0/0
moving on.......
9.5 - OSPF DR and BDR Elections
EachRouter(config)#
hostname X (A, B, or C)
EachRouter(config)#
line con 0
EachRouter(config-line)#
exec-timeout 0 0
A(config)#
int f0/0
A(config-if)#
ip addr 10.1.1.1 255.255.255.0
A(config-if)#
no shut
A(config)#
router ospf 12345
A(config-router)#
net 10.1.1.0 0.0.0.255 area 0
00:23:30: %OSPF-5-ADJCHG: Process 12345, Nbr 10.1.1.3 on FastEthernet0/0 from LOADING to FULL, Loading Done
00:23:30: %OSPF-5-ADJCHG: Process 12345, Nbr 10.1.1.2 on FastEthernet0/0 from LOADING to FULL, Loading Done
A#
show ip ospf int
note this output was generated AFTER all 3 routers set for OSPF
FastEthernet0/0 is up, line protocol is up
Internet address is 10.1.1.1/24, Area 0
Process ID 12345, Router ID 10.1.1.1, Network Type BROADCAST, Cost: 1
Transmit Delay is 1 sec, State DROTHER, Priority 1
Designated Router (ID) 10.1.1.3, Interface address 10.1.1.3
Backup Designated Router (ID) 10.1.1.2, Interface address 10.1.1.2
Timer intervals configured, Hello 10, Dead 40, Wait 40, Retransmit 5
Hello due in 00:00:04
Index 1/1, flood queue length 0
Next 0x0(0)/0x0(0)
Last flood scan length is 1, maximum is 1
Last flood scan time is 0 msec, maximum is 0 msec
Neighbor Count is 2, Adjacent neighbor count is 2
Adjacent with neighbor 10.1.1.3 (Designated Router)
Adjacent with neighbor 10.1.1.2 (Backup Designated Router)
Suppress hello for 0 neighbor(s)
A(config-if)#shut
A(config-if)#
%LINK-5-CHANGED: Interface FastEthernet0/0, changed state to administratively down
%LINEPROTO-5-UPDOWN: Line protocol on Interface FastEthernet0/0, changed state to down
00:40:28: %OSPF-5-ADJCHG: Process 12345, Nbr 10.1.1.2 on FastEthernet0/0 from FULL to DOWN, Neighbor Down: Interface down or detached
00:40:28: OSPF: Build router LSA for area 0, router ID 10.1.1.1, seq 0xffffffff80000003
00:40:28: %OSPF-5-ADJCHG: Process 12345, Nbr 10.1.1.3 on FastEthernet0/0 from FULL to DOWN, Neighbor Down: Interface down or detached
00:40:28: OSPF: Build router LSA for area 0, router ID 10.1.1.1, seq 0xffffffff80000004
00:40:28: OSPF: Build router LSA for area 0, router ID 10.1.1.1, seq 0xffffffff80000004
A(config-if)#no shut
A(config-if)#
%LINK-5-CHANGED: Interface FastEthernet0/0, changed state to up
%LINEPROTO-5-UPDOWN: Line protocol on Interface FastEthernet0/0, changed state to up
00:40:48: OSPF: Build router LSA for area 0, router ID 10.1.1.1, seq 0xffffffff80000004
00:41:27: OSPF: Backup seen Event before WAIT timer on FastEthernet0/0
00:41:27: OSPF: DR/BDR election on FastEthernet0/0
00:41:27: OSPF: Elect BDR 10.1.1.2
00:41:27: OSPF: Elect DR 10.1.1.3
00:41:27: DR: 10.1.1.3 (Id) BDR: 10.1.1.2 (Id)
00:41:27: OSPF: Send DBD to 10.1.1.3 on FastEthernet0/0 seq 0x5accb8e2 opt 0x00 flag 0x7 len 32
B(config)#
int f0/0
B(config-if)#
ip addr 10.1.1.2 255.255.255.0
B(config-if)#
no shut
B(config)#
router ospf 12345
B(config-router)#
net 10.1.1.0 0.0.0.255 area 0
00:23:29: %OSPF-5-ADJCHG: Process 12345, Nbr 10.1.1.3 on FastEthernet0/0 from LOADING to FULL, Loading Done
00:23:29: %OSPF-5-ADJCHG: Process 12345, Nbr 10.1.1.1 on FastEthernet0/0 from LOADING to FULL, Loading Done
B#
show ip ospf int
note this output was generated AFTER all 3 routers set for OSPF
FastEthernet0/0 is up, line protocol is up
Internet address is 10.1.1.2/24, Area 0
Process ID 12345, Router ID 10.1.1.2, Network Type BROADCAST, Cost: 1
Transmit Delay is 1 sec, State BDR, Priority 1
Designated Router (ID) 10.1.1.3, Interface address 10.1.1.3
Backup Designated Router (ID) 10.1.1.2, Interface address 10.1.1.2
Timer intervals configured, Hello 10, Dead 40, Wait 40, Retransmit 5
Hello due in 00:00:05
Index 1/1, flood queue length 0
Next 0x0(0)/0x0(0)
Last flood scan length is 1, maximum is 1
Last flood scan time is 0 msec, maximum is 0 msec
Neighbor Count is 2, Adjacent neighbor count is 2
Adjacent with neighbor 10.1.1.1
Adjacent with neighbor 10.1.1.3 (Designated Router)
Suppress hello for 0 neighbor(s)
B#debug ip ospf adj
OSPF adjacency events debugging is on
B#
00:39:21: OSPF: DR/BDR election on FastEthernet0/0
00:39:21: OSPF: Elect BDR 10.1.1.2
00:39:21: OSPF: Elect DR 10.1.1.3
00:39:21: DR: 10.1.1.3 (Id) BDR: 10.1.1.2 (Id)
00:41:01: %OSPF-5-ADJCHG: Process 12345, Nbr 10.1.1.1 on FastEthernet0/0 from FULL to DOWN, Neighbor Down: Dead timer expired
00:41:01: %OSPF-5-ADJCHG: Process 12345, Nbr 10.1.1.1 on FastEthernet0/0 from FULL to DOWN, Neighbor Down: Interface down or detached
00:41:01: OSPF: Build router LSA for area 0, router ID 10.1.1.2, seq 0xffffffff80000003
00:41:01: OSPF: DR/BDR election on FastEthernet0/0
00:41:01: OSPF: Elect BDR 10.1.1.2
00:41:01: OSPF: Elect DR 10.1.1.3
C(config)#
int f0/0
C(config-if)#
ip addr 10.1.1.3 255.255.255.0
C(config-if)#
no shut
C(config)#
router ospf 12345
C(config-router)#
net 10.1.1.0 0.0.0.255 area 0
00:23:27: %OSPF-5-ADJCHG: Process 12345, Nbr 10.1.1.1 on FastEthernet0/0 from LOADING to FULL, Loading Done
00:23:27: %OSPF-5-ADJCHG: Process 12345, Nbr 10.1.1.2 on FastEthernet0/0 from LOADING to FULL, Loading Done
C#
show ip ospf int
note this output was generated AFTER all 3 routers set for OSPF
FastEthernet0/0 is up, line protocol is up
Internet address is 10.1.1.3/24, Area 0
Process ID 12345, Router ID 10.1.1.3, Network Type BROADCAST, Cost: 1
Transmit Delay is 1 sec, State DR, Priority 1
Designated Router (ID) 10.1.1.3, Interface address 10.1.1.3
Backup Designated Router (ID) 10.1.1.2, Interface address 10.1.1.2
Timer intervals configured, Hello 10, Dead 40, Wait 40, Retransmit 5
Hello due in 00:00:00
Index 1/1, flood queue length 0
Next 0x0(0)/0x0(0)
Last flood scan length is 1, maximum is 1
Last flood scan time is 0 msec, maximum is 0 msec
Neighbor Count is 2, Adjacent neighbor count is 2
Adjacent with neighbor 10.1.1.1
Adjacent with neighbor 10.1.1.2 (Backup Designated Router)
Suppress hello for 0 neighbor(s)
C#debug ip ospf adj
OSPF adjacency events debugging is on
C#
00:39:19: OSPF: DR/BDR election on FastEthernet0/0
00:39:19: OSPF: Elect BDR 10.1.1.2
00:39:19: OSPF: Elect DR 10.1.1.3
00:39:19: DR: 10.1.1.3 (Id) BDR: 10.1.1.2 (Id)
00:40:59: %OSPF-5-ADJCHG: Process 12345, Nbr 10.1.1.1 on FastEthernet0/0 from FULL to DOWN, Neighbor Down: Dead timer expired
00:40:59: %OSPF-5-ADJCHG: Process 12345, Nbr 10.1.1.1 on FastEthernet0/0 from FULL to DOWN, Neighbor Down: Interface down or detached
00:40:59: OSPF: Build router LSA for area 0, router ID 10.1.1.3, seq 0xffffffff80000003
00:40:59: OSPF: Build net LSA for area 0, router ID 10.1.1.3, seq 0xffffffff80000003
00:40:59: OSPF: DR/BDR election on FastEthernet0/0
00:40:59: OSPF: Elect BDR 10.1.1.2
00:40:59: OSPF: Elect DR 10.1.1.3
DR and BDR automtically set based on higest IP address
Note our network type is BROADCAST because we're using ethernet interfaces...
it would be point-to-point if using a serial connection
we want to manually overide the priority of the router. ZERO priority means it wont participate in the election process
MAX priority of 255 means no other router can beat it for DR
We'll set the priority for router A to 3.
It will beome the DR only after we shut/no shut the interface router
AND
manually power on/off the other two routers
A(config)#
int f0/0
A(config-int)#
ip ospf priority 3
A(config-int)#
shut
A(config-int)#
no shut
A#
debug ip ospf adj
B#
debug ip ospf adj
00:05:50: OSPF: DR/BDR election on FastEthernet0/0
00:05:50: OSPF: Elect BDR 10.1.1.2
00:05:50: OSPF: Elect DR 10.1.1.1
00:05:50: OSPF: Elect BDR 10.1.1.2
00:05:50: OSPF: Elect DR 10.1.1.1
00:05:50: DR: 10.1.1.1 (Id) BDR: 10.1.1.2 (Id)
00:05:50: OSPF: Send DBD to 10.1.1.1 on FastEthernet0/0 seq 0x10164ebb opt 0x00 flag 0x7 len 32
00:05:50: OSPF: Build router LSA for area 0, router ID 10.1.1.2, seq 0xffffffff80000002
00:05:52: OSPF: Rcv DBD from 10.1.1.1 on FastEthernet0/0 seq 0x20368093 opt 0x00 flag 0x7 len 32 mtu 1500 state EXSTART
00:05:52: OSPF: First DBD and we are not SLAVE
00:05:55: OSPF: Send DBD to 10.1.1.1 on FastEthernet0/0 seq 0x10164ebb opt 0x00 flag 0x7 len 32
00:05:55: OSPF: Rcv DBD from 10.1.1.1 on FastEthernet0/0 seq 0x10164ebb opt 0x00 flag 0x2 len 112 mtu 1500 state EXSTART
00:05:55: OSPF: NBR Negotiation Done. We are the MASTER
00:05:55: OSPF: Send DBD to 10.1.1.1 on FastEthernet0/0 seq 0x10164ebc opt 0x00 flag 0x3 len 52
00:05:55: OSPF: Rcv DBD from 10.1.1.1 on FastEthernet0/0 seq 0x10164ebc opt 0x00 flag 0x0 len 32 mtu 1500 state EXCHANGE
00:05:55: OSPF: Send DBD to 10.1.1.1 on FastEthernet0/0 seq 0x10164ebd opt 0x00 flag 0x1 len 32
00:05:55: OSPF: Rcv DBD from 10.1.1.1 on FastEthernet0/0 seq 0x10164ebd opt 0x00 flag 0x0 len 32 mtu 1500 state EXCHANGE
00:05:55: Exchange Done with 10.1.1.1 on FastEthernet0/0
00:05:55: OSPF: Database request to 10.1.1.1
00:05:55: OSPF: sent LS REQ packet to 10.1.1.1, length 36
00:05:55: OSPF: Rcv DBD from 10.1.1.1 on FastEthernet0/0 seq 0x10164ebd opt 0x00 flag 0x0 len 32 mtu 1500 state LOADING
00:05:55: Synchronized with with 10.1.1.1 on FastEthernet0/0, state FULL
00:05:55: %OSPF-5-ADJCHG: Process 12345, Nbr 10.1.1.1 on FastEthernet0/0 from LOADING to FULL, Loading Done
00:05:55: OSPF: Build router LSA for area 0, router ID 10.1.1.2, seq 0xffffffff80000002
C#
debug ip ospf adj
00:06:13: OSPF: DR/BDR election on FastEthernet0/0
00:06:13: OSPF: Elect BDR 10.1.1.2
00:06:13: OSPF: Elect DR 10.1.1.1
00:06:13: DR: 10.1.1.1 (Id) BDR: 10.1.1.2 (Id)
00:06:13: OSPF: Send DBD to 10.1.1.1 on FastEthernet0/0 seq 0x1cc5536d opt 0x00 flag 0x7 len 32
00:06:13: OSPF: Send DBD to 10.1.1.2 on FastEthernet0/0 seq 0x3d51ca66 opt 0x00 flag 0x7 len 32
00:06:13: OSPF: Build router LSA for area 0, router ID 10.1.1.3, seq 0xffffffff80000002
00:06:17: OSPF: Rcv DBD from 10.1.1.1 on FastEthernet0/0 seq 0x6b532eec opt 0x00 flag 0x7 len 32 mtu 1500 state EXSTART
00:06:17: OSPF: First DBD and we are not SLAVE
00:06:17: OSPF: Rcv DBD from 10.1.1.2 on FastEthernet0/0 seq 0x783110f4 opt 0x00 flag 0x7 len 32 mtu 1500 state EXSTART
00:06:17: OSPF: First DBD and we are not SLAVE
00:06:18: OSPF: Send DBD to 10.1.1.2 on FastEthernet0/0 seq 0x3d51ca66 opt 0x00 flag 0x7 len 32
00:06:18: OSPF: Send DBD to 10.1.1.1 on FastEthernet0/0 seq 0x1cc5536d opt 0x00 flag 0x7 len 32
00:06:18: OSPF: Rcv DBD from 10.1.1.2 on FastEthernet0/0 seq 0x3d51ca66 opt 0x00 flag 0x2 len 132 mtu 1500 state EXSTART
00:06:18: OSPF: NBR Negotiation Done. We are the MASTER
00:06:18: OSPF: Send DBD to 10.1.1.2 on FastEthernet0/0 seq 0x3d51ca67 opt 0x00 flag 0x3 len 52
00:06:18: OSPF: Rcv DBD from 10.1.1.1 on FastEthernet0/0 seq 0x1cc5536d opt 0x00 flag 0x2 len 132 mtu 1500 state EXSTART
00:06:18: OSPF: NBR Negotiation Done. We are the MASTER
00:06:18: OSPF: Send DBD to 10.1.1.1 on FastEthernet0/0 seq 0x1cc5536e opt 0x00 flag 0x3 len 52
00:06:18: OSPF: Rcv DBD from 10.1.1.2 on FastEthernet0/0 seq 0x3d51ca67 opt 0x00 flag 0x0 len 32 mtu 1500 state EXCHANGE
00:06:18: OSPF: Send DBD to 10.1.1.2 on FastEthernet0/0 seq 0x3d51ca68 opt 0x00 flag 0x1 len 32
00:06:18: OSPF: Rcv DBD from 10.1.1.1 on FastEthernet0/0 seq 0x1cc5536e opt 0x00 flag 0x0 len 32 mtu 1500 state EXCHANGE
00:06:18: OSPF: Send DBD to 10.1.1.1 on FastEthernet0/0 seq 0x1cc5536f opt 0x00 flag 0x1 len 32
00:06:18: OSPF: Rcv DBD from 10.1.1.2 on FastEthernet0/0 seq 0x3d51ca68 opt 0x00 flag 0x0 len 32 mtu 1500 state EXCHANGE
00:06:18: Exchange Done with 10.1.1.2 on FastEthernet0/0
00:06:18: OSPF: Database request to 10.1.1.2
00:06:18: OSPF: sent LS REQ packet to 10.1.1.2, length 48
00:06:18: OSPF: Rcv DBD from 10.1.1.1 on FastEthernet0/0 seq 0x1cc5536f opt 0x00 flag 0x0 len 32 mtu 1500 state EXCHANGE
verify on all three routers
A#
show ip ospf interface f0/0
FastEthernet0/0 is up, line protocol is up
Internet address is 10.1.1.1/24, Area 0
Process ID 12345, Router ID 10.1.1.1, Network Type BROADCAST, Cost: 1
Transmit Delay is 1 sec, State DR, Priority 3
Designated Router (ID) 10.1.1.1, Interface address 10.1.1.1
Backup Designated Router (ID) 10.1.1.2, Interface address 10.1.1.2
Timer intervals configured, Hello 10, Dead 40, Wait 40, Retransmit 5
Hello due in 00:00:09
Index 1/1, flood queue length 0
Next 0x0(0)/0x0(0)
Last flood scan length is 1, maximum is 1
Last flood scan time is 0 msec, maximum is 0 msec
Neighbor Count is 2, Adjacent neighbor count is 2
Adjacent with neighbor 10.1.1.2 (Backup Designated Router)
Adjacent with neighbor 10.1.1.3
Suppress hello for 0 neighbor(s)
A#
show ip ospf neighbor
Neighbor ID Pri State Dead Time Address Interface
10.1.1.2 1 FULL/BDR 00:00:37 10.1.1.2 FastEthernet0/0
10.1.1.3 1 FULL/DROTHER 00:00:30 10.1.1.3 FastEthernet0/0
B#
show ip ospf interface f0/0
FastEthernet0/0 is up, line protocol is up
Internet address is 10.1.1.2/24, Area 0
Process ID 12345, Router ID 10.1.1.2, Network Type BROADCAST, Cost: 1
Transmit Delay is 1 sec, State BDR, Priority 1
Designated Router (ID) 10.1.1.1, Interface address 10.1.1.1
Backup Designated Router (ID) 10.1.1.2, Interface address 10.1.1.2
Timer intervals configured, Hello 10, Dead 40, Wait 40, Retransmit 5
Hello due in 00:00:08
Index 1/1, flood queue length 0
Next 0x0(0)/0x0(0)
Last flood scan length is 1, maximum is 1
Last flood scan time is 0 msec, maximum is 0 msec
Neighbor Count is 2, Adjacent neighbor count is 2
Adjacent with neighbor 10.1.1.1 (Designated Router)
Adjacent with neighbor 10.1.1.3
Suppress hello for 0 neighbor(s)
B#
show ip ospf neighbor
Neighbor ID Pri State Dead Time Address Interface
10.1.1.1 3 FULL/DR 00:00:35 10.1.1.1 FastEthernet0/0
10.1.1.3 1 FULL/DROTHER 00:00:31 10.1.1.3 FastEthernet0/0
C#
show ip ospf interface f0/0
FastEthernet0/0 is up, line protocol is up
Internet address is 10.1.1.3/24, Area 0
Process ID 12345, Router ID 10.1.1.3, Network Type BROADCAST, Cost: 1
Transmit Delay is 1 sec, State DROTHER, Priority 1
Designated Router (ID) 10.1.1.1, Interface address 10.1.1.1
Backup Designated Router (ID) 10.1.1.2, Interface address 10.1.1.2
Timer intervals configured, Hello 10, Dead 40, Wait 40, Retransmit 5
Hello due in 00:00:06
Index 1/1, flood queue length 0
Next 0x0(0)/0x0(0)
Last flood scan length is 1, maximum is 1
Last flood scan time is 0 msec, maximum is 0 msec
Neighbor Count is 2, Adjacent neighbor count is 2
Adjacent with neighbor 10.1.1.1 (Designated Router)
Adjacent with neighbor 10.1.1.2 (Backup Designated Router)
Suppress hello for 0 neighbor(s)
C#
show ip ospf neighbor/span>
Neighbor ID Pri State Dead Time Address Interface
10.1.1.1 3 FULL/DR 00:00:35 10.1.1.1 FastEthernet0/0
10.1.1.2 1 FULL/BDR 00:00:37 10.1.1.2 FastEthernet0/0
Router1 is the DR with priority 3
still need more work to understand the output of the defbu ospf adj
Chapter 9 Review Questions
1. There are three possible routes for a router to reach a destination network:
OSPF with a metric of 782
RIPv2 with a metric of 4
EIGRP with a composite metric of 20514560
Which route will be installed in the routing table?
EIGRP because it has the lowest Administrative Distance, and AD is always used before metric
ADs are:
ExternalEIGRP 170
RIP 120
OSPF 110
IGRP 100
EIGRP 90
Static 1
Connected 0
2. Which EIGRP information is held in RAM and maintained through the use of Hello and update packets?
Neighbor table
and
toplogy table
3. Describe the process identifier that is used to run OSPF on a router
The OSPF process id is only locally significant. A random number can be selected. But it's required in order to identify
a unique OSPF database instance. You can use the same, or a different number on each router, doesnt matter.
Any number can be used from 1 to 65,535. Process ID is supplied as an argument to the command router ospf
NOT to be confused with the area number which can be any number up to 4 billion. The area id identifies a logical grouping of routers.
area id is supplied as argument to the OSPF network id and mask command
Ex:
R1(config)#
router ospf 12345
R1(config-router)#
net 10.1.1.0 0.0.0.255 area 0
4. Where are EIGRP successor routes stored?
EIGRP succesor routers are stored in the routing table. The "succesor" is the successful or primary route.
The successor route is ALSO listed in the topology table,
The feasible successor is a BACKUP route and will ONLY be listed in the topology table, unless the successor route fails,
in which case the feasible successor would become the successor
Note that my EIGRP setup doesnt seem to folow this.
CTRL-F jump to "remotely connected via remote ingress ip address"
the book states that EIGRP is automatically load-balancing our two links from R1 to corp.. is this why there is no feasible successor here?
I did some research and found that in our case, we are not using a Feasible Successor. You CAN have two Successors with equal metric, in which case EIGRP will
automatically load-balance.
But I wanted to find out what a Feasible Successor actually looks like in the EIGRP topology table..
Kevin Wallace EIGRP article
Conclusion:
EIGRP topology table wouldnt specifically say "Feasible Successor", but you would know by two routes appearing, one with a lower metric.
In my topology we have two equal-metric links and they are both considered "Successors". EIGRP uses them equally (load-balanced)
Corp#
show ip eigrp toplogy
[cut]
P 172.16.10.0/24, 1 successors, FD is 28160
via 10.1.5.2 (28160/25600), FastEthernet0/0
P 192.168.10.0/24, 2 successors, FD is 2172416
via 10.1.3.2 (2172416/28160), Serial0/0/1
via 10.1.2.2 (2172416/28160), Serial0/0/0
P 192.168.20.0/24, 2 successors, FD is 2172416
via 10.1.3.2 (2172416/28160), Serial0/0/1
via 10.1.2.2 (2172416/28160), Serial0/0/0
P 192.168.30.0/24, 1 successors, FD is 2172416
via 10.1.4.2 (2172416/28160), Serial0/1/0
P 192.168.40.0/24, 1 successors, FD is 2172416
via 10.1.4.2 (2172416/28160), Serial0/1/0
5. Which command will display all the EIGRP feasible successor routes to a known router.
show ip eigrp topology
6. Find the configuration error. You type the following into your router, but dont see any routes in the routing table?
Router(config)#
router ospf 1
Router(config-router)#
network 10.0.0.0 255.0.0.0
wrong wildcard mask
instead, could have used
0.255.255.255
or
0.0.0.255
the point is we need to specify the first octet as "allowed" into our OSPF config with a 0 mask.
The remaining bits are 'dont care' bits aka 'wildcard' aka 255
7. Which three protocols support VLSM, summarization, and discontigous networking?
RIPv2
EIGRP
OSPF
all 3 build and mainting routing tables, provide classless routing which allows VLSM, summarization, and discontigous networks
RIPv1 and IGRP build/maintain routing tables, but dont offer classless routing
8. Which are true regarding OSPF areas?
the 'backbone' is area 0
if using other areas, they all must directly connect to area 0
9. Which two network types have a designated router and a backup designated router?
Broadcast
NBMA- Non broadcast multi access. Ex: Frame Relay
network types that DO NOT use DR/BDR:
point to point
broadcast multipoint
10. You need to configure a router with a distance-vector protocol that allows classless routing. Which to use?
EIGRP is considered 'advanced distance vector' (ripv2 wasnt an option)
11. You need the IP address of the devices with which the router has established an adjacency.
Also, the retransmit interval and the queue counts for the adjacent routers need to be checked. What command will display the required information?
show ip eigrp neighbors
WRONG: show ip eigrp adjacency - there is no such command.. the word 'adjacency' is only used with debug ip OSPF adjacency
here are the possible commands for show ip eigrp and debug ip eigrp
show ip eigrp ?
interfaces IP-EIGRP interfaces
neighbors IP-EIGRP neighbors
topology IP-EIGRP Topology Table
traffic IP-EIGRP Traffic Statistics
debug ip eigrp ?
summary IP-EIGRP summary route processing
12. You cant establish an adjacency relationship on a common ethernet link between two routers. Based on the output below, what is the cause of the problem?
RouterA#
Ethernet0/0 is up, line protocol is up
Internet Address 172.16.1.2/16, Area 0
Process ID 2, Router ID 172.126.1.2, Network Type BROADCAST, Cost: 10
Transmit Delay is 1 sec, State DR, Priority 1
Designated Router (ID) 172.16.1.2, interface address 172.16.1.1.
No backup designated router on this network
Timer intervals configured, Hello 5, Dead 20, Wait 20, Retransmit 5
Router B#
Internet Address 172.16.1.1/16, Area 0
Process ID 2, Router ID 172.126.1.1, Network Type BROADCAST, Cost: 10
Transmit Delay is 1 sec, State DR, Priority 1
Designated Router (ID) 172.16.1.1, interface address 172.16.1.2.
No backup designated router on this network
Timer intervals configured, Hello 10, Dead 40, Wait 40, Retransmit 5
mismatched timer intervals
OSPF default Hello is 10 and Dead is 40... RouterA was modified
13. Which is true regarding EIGRP successor routes?
Used in the routing table
also appears in the topolgy table
may (or may not) have a backup feasabile successor
14. Which type of OSPF network will elect a backup designated router?
broadcast multi-access
non-broadcast multiaccess
types of network that will NOT elect a BDR:
point to point and brodacast multipoint (hub/spoke topology)
15. Which two commands will place network 10.2.3.0/24 into area 0?
Router(config)#
router ospf 10
Router(config-router)#
network 10.2.3.0 0.0.0.255 area 0
16. With which network type will OSPF establish router adjacencies but not perform the DR/BDR election process?
Point to point
no election process occurs, there is never a DR on point to point
17. What are three reasons for creating OSPF in a heirarchical design?
decrease routing overhead
speed up convergence
confine stability to single areas of the network
18. What is the administrative distance of OSPF?
110
19.
no auto summary
the network is considered discontigous because we have two classful network subnetted (on the left and right),
seperated by a different classful address.
if auto summarization is taking place, the routers cant determine which side is which because both sides would be summarized as
Class B, 172.16.0.0, which isnt specific enough to distinguish between the sides.
20. IF routers in a single area are configured with the same priority value, what value does a router use for the OSPF router ID in the absence of a loopback interface?
The highest IP of any PHSYICAL interface.
Trick question. Highest IP of any LOGICAL interface is an option. And is correct IF you had logical interfaces, but the question
states that any "logical interfaces are absent".
At OSPF startup, the highest IP of *any* active interface on the router becomes the OSPF router ID. If you have loopback (logical) interfaces configured,
one of them (the largest IP) will *override* the phsyical interfaces and the loopback IP becomes the RID.
Reference for which loopback (if multiple) wins:
packetpushers.net
------------------------------------------------------------------------------
END CHAPTER 9
41 hours 2-14 thru 2-28-22
original total 184 hours
14 hours review 12-26 thru 12-28-22
review total hours 46
book page 502/822
184 + 46 = 230 hours * 60 = (13,800 min) / 500 pages =
avg 28 min/page (includes reading and exercises/labs + online research)
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LabA(config)#
int s0/0/0
LabA(config-if)# ip addr 172.16.20.1
LabA(config-if)# int f0/0
LabA(config-if)# ip addr 172.16.10.1
-----------------------------------------------------------------
LabA(config)# ip route 172.16.30.0 255.255.255.0 172.16.20.2
LabA(config)# ip route 172.16.40.0 255.255.255.0 172.16.20.2
LabA(config-if)# ip addr 172.16.20.1
LabA(config-if)# int f0/0
LabA(config-if)# ip addr 172.16.10.1
-----------------------------------------------------------------
LabA(config)# ip route 172.16.30.0 255.255.255.0 172.16.20.2
LabA(config)# ip route 172.16.40.0 255.255.255.0 172.16.20.2
LabB(config)#
int s0/0/0
LabB(config-if)# ip addr 172.16.20.2
LabB(config-if)# int s0/0/1
LabB(config-if)# ip addr 172.16.30.1
-----------------------------------------------------------------
LabB(config)# ip route 172.16.10.0 255.255.255.0 172.16.20.1
LabB(config)# ip route 172.16.40.0 255.255.255.0 172.16.30.2
LabB(config-if)# ip addr 172.16.20.2
LabB(config-if)# int s0/0/1
LabB(config-if)# ip addr 172.16.30.1
-----------------------------------------------------------------
LabB(config)# ip route 172.16.10.0 255.255.255.0 172.16.20.1
LabB(config)# ip route 172.16.40.0 255.255.255.0 172.16.30.2
LabC(config)#
int s0/0/0
LabC(config-if)# ip addr 172.16.30.2
LabC(config-if)# int f0/0
LabC(config-if)# ip addr 172.16.40.1
-----------------------------------------------------------------
LabC(config)# ip route 172.16.10.0 255.255.255.0 172.16.30.1
LabC(config)# ip route 172.16.20.0 255.255.255.0 172.16.30.1
LabC(config-if)# ip addr 172.16.30.2
LabC(config-if)# int f0/0
LabC(config-if)# ip addr 172.16.40.1
-----------------------------------------------------------------
LabC(config)# ip route 172.16.10.0 255.255.255.0 172.16.30.1
LabC(config)# ip route 172.16.20.0 255.255.255.0 172.16.30.1
LabA(config)#
no ip route 172.16.30.0 255.255.255.0 172.16.20.2
LabA(config)# no ip route 172.16.40.0 255.255.255.0 172.16.20.2
LabA(config)# router rip
LabA(config-router)# network 172.16.0.0
LabA(config-router)# do show ip route
LabA(config)# no ip route 172.16.40.0 255.255.255.0 172.16.20.2
LabA(config)# router rip
LabA(config-router)# network 172.16.0.0
LabA(config-router)# do show ip route
Gateway of last resort is not set
172.16.0.0/16 is variably subnetted, 5 subnets, 2 masks
C 172.16.10.0/24 is directly connected, FastEthernet0/0
L 172.16.10.1/32 is directly connected, FastEthernet0/0
C 172.16.20.0/24 is directly connected, Serial0/0/0
L 172.16.20.1/32 is directly connected, Serial0/0/0
R 172.16.30.0/24 [120/1] via 172.16.20.2, 00:00:07, Serial0/0/0
from Lab B
LabB(config)#
no ip route 172.16.10.0 255.255.255.0 172.16.20.1
LabB(config)# no ip route 172.16.40.0 255.255.255.0 172.16.30.2
LabB(config)# router rip
LabB(config-router)# network 172.16.0.0
LabB(config-router)# do show ip route
LabB(config)# no ip route 172.16.40.0 255.255.255.0 172.16.30.2
LabB(config)# router rip
LabB(config-router)# network 172.16.0.0
LabB(config-router)# do show ip route
Gateway of last resort is not set
172.16.0.0/16 is variably subnetted, 5 subnets, 2 masks
R 172.16.10.0/24 [120/1] via 172.16.20.1, 00:00:13, Serial0/0/0
from LabA
C 172.16.20.0/24 is directly connected, Serial0/0/0
L 172.16.20.2/32 is directly connected, Serial0/0/0
C 172.16.30.0/24 is directly connected, Serial0/0/1
L 172.16.30.1/32 is directly connected, Serial0/0/1
LabC(config)#
no ip route 172.16.10.0 255.255.255.0 172.16.30.1
LabC(config)# no ip route 172.16.20.0 255.255.255.0 172.16.30.1
LabC(config)# router rip
LabC(config-router)# network 172.16.0.0
LabC(config-router)# do show ip route
LabC(config)# no ip route 172.16.20.0 255.255.255.0 172.16.30.1
LabC(config)# router rip
LabC(config-router)# network 172.16.0.0
LabC(config-router)# do show ip route
Gateway of last resort is not set
172.16.0.0/16 is variably subnetted, 3 subnets, 2 masks
R 172.16.20.0/24 [120/1] via 172.16.30.1, 00:00:05, Serial0/0/0
from LabB
C 172.16.30.0/24 is directly connected, Serial0/0/0
L 172.16.30.2/32 is directly connected, Serial0/0/0
1. The Acme company uses a router named Gateway to connect to its ISP. The address of the ISP router is 206.143.5.2.
Which three commands could be configured on the gateway router to allow internet access to the entire network?
Set a default route:
Gateway(config)# ip route 0.0.0.0 0.0.0.0 206.143.5.2 next hop IP
Gateway(config)# ip route 0.0.0.0 0.0.0.0 S/0 exit interface instead of next hop IP
Gateway(config)# ip default-network 206.143.5.0 next hop IP
Gateway(config)# ip route 0.0.0.0 0.0.0.0 206.143.5.2 next hop IP
Gateway(config)# ip route 0.0.0.0 0.0.0.0 S/0 exit interface instead of next hop IP
Gateway(config)# ip default-network 206.143.5.0 next hop IP
2. What command will prevent RIP routing updates from exiting an interface but will sill allow the interface to receive RIP updates?
Router(config-if)#
passive-interface
3. Which two statemnts are true about ip route 172.16.4.0 255.255.255.0 192.168.4.2?
the command establishes a static route
the default admin distance is used (since we didnt give an AD argument)
the default admin distance is used (since we didnt give an AD argument)
4. What two destination addresses will be used by HostA to send data to the HTTPS server as shown in the following network?
MAC of RouterA f0/0 interface
IP address of the server
5. Which two statements are true about this output?
RIP: received v1 update from 192.168.40.2 on S0/1
192.168.50.0 in 16 hops (inaccessible)
RIP: sending v1 update to 255.255.255.255 via F0/0 (192.168.30.1)
RIP: build update entries
network 192.168.20.0 metric 1
network 192.168.40.0 metric 1
network 192.168.50.0 metric 16
RIP: sending v1 update to 255.255.255.255 via S0/1 (192.168.40.1)
true:
there are at least two routers exchanging information
192.168.40.2 will be successful
FALSE
there are three interfaces on the router participating in this update
false because we only see two interfaces represented in the output: S0/1(twice) and F0/0
a ping to 192.168.50.1 will be successful
false because that route has a metric of 16; it's unreachable
there are at least two routers exchanging information
192.168.40.2 will be successful
FALSE
there are three interfaces on the router participating in this update
false because we only see two interfaces represented in the output: S0/1(twice) and F0/0
a ping to 192.168.50.1 will be successful
false because that route has a metric of 16; it's unreachable
6. Describe split horizon
will not advertise a route back the the same router it was learned from
7. Which would be true if HostA is trying to communicate to HostB and interface F0/0 of RouterC goes down, as shown in the graphic?
RouterC will send an ICMP 'destination unreachable type' message to inform HostA that HostB is unreachable
8. Which two statements are true regarding classless routing protocols?
VLSM is permitted
RIPv2 supports classless
RIPv2 supports classless
9. Which two are true regarding distance-vector vs link-state?
Distance vector sends the whole routing table out all active interfaces(even if a router isnt on the other end)at periodic time intervals
Link-state sends updates containing the state of its own links to all routers in the inter-network
Link-state sends updates containing the state of its own links to all routers in the inter-network
10. Which command display RIP routing updates?
debug ip rip
11. What does RIPv2 use to prvent routing loops?
split horizon stops an update from being send on the same interface it was received
holdown timers allow time for a network to become stable in the case of a flapping link
holdown timers allow time for a network to become stable in the case of a flapping link
12. A network administrator views the output from the show ip route command. A network that is advertised
by both RIP and EIGRP appears in the routing table flagged an EIGRP route. Why is the RIP route to this network not used in this routing table?
EIGRP has a lower AD.
RIP=120
OSPP=110
IGRP=110
EIGRP=90
RIP=120
OSPP=110
IGRP=110
EIGRP=90
13. You type debug ip rip on your router console and see that 172.16.10.0 is being advertised to you with a metric of 16. What does this mean?
it is inaccessible. in RIP if you see a route advertised with a metric of 16, it's inaccessible
14. What metric does RIPv2 use to find the best path to the remote network?
distance aka hop count
15. The Corporate router receives an IP packet with a source IP address of 192.168.214.20 and a destination address of 192.168.22.3. Looking at the output from the Corp router,
what will the router do with this packet?
Corp# show ip route
[cut]
R 192.168.215.0 [120/2] via 192.168.20.2, Serail0/0
R 192.168.115.0 [120/1] via 192.168.20.0, Serial0/0
R 192.168.30.0 [120/1] via 192.168.20.2, Serial0/0
C 192.168.20.0 is directly connected, Serial0/0
C 192.168.214.0 is directly connected, FastEthernet0/0
Since there is no route to that network, the router will discard the packet and send an ICMP destination unreachable message out F0/0 back the the source network
16. If your routing table has a static, a RIP and an EIGRP route to the same network, which route will be used by default?
Static routes have an admin distance of 1 by default. Unless you change it, a static route will always be used over any other
dynamically learned route.
17. You have the following routing table. Which network will NOT be placed in the neighbor routing table?
R 192.168.30.0/24 [120/1] via 192.168.40.1, Serial 0
C 192.168.40.0/24 is directly connected, Serial 0
172.16.0.0/2 is subnetted, 1 subnets
C 172.16.30.0 is directly connected, Loopback0
R 192.168.20.0/24 [120/1] via 192.168.40.1, Serial 0
R 10.0.0.0/8 [120/15] via 192.168.40.1, Serial 0
C 192.168.50.0/24 is directly connected, Ethernet 0
10.0.0.0 cant be placed in neighboring routing table because it is at 15 hops. 16 hops is invalid in RIP
18. Two connected routers are configured only with RIP. What will be the result when a router receives a routing update that contains a
higher-cost path to a network already in it's routing table?
The router will ignore the update because it is higher cost. When a routing update is received, the router first checks the AD and always chooses
the route with the lowest AD.
19.Which is true about route poisoning?
The router sets the metric for a downed link to "infinity".
20. Which is true about RIPv2?
it has all the same timers as RIPv1
------------------------------------------------------------------------------
END CHAPTER 8
54 hours 1-28 thru 2-14-22
original total 143 hours
11.5 hours review 12-23,24,26-22
review total hours 32
book page 428/822
avg 20 min/page (reading and exercises/labs)
Chapter 9 EIGRP and OSPF
pages 427-502, start 2-14-22-MWhat is EIGRP? Note it's not officially on CCNA 200-301 but it is still important to learn
Enhanced IGRP is a classless, enchanced distance vector protocol that uses the concept of an autonomous system to describe the set of contigous routers that run the same routing protocol and share routing information.
Features:
Support for IP and IPv6 via protocol-dependent modules (seperate routing tables)
Considered classless
Support for summaries and discontiguous networks
Eficient neighbor discovery
communication via RTP- Reliable Transport Protocol
best path selection via Diffusing Updae Algorithm DUAL
Cisco considers EIGRP a "distance-vector" routing protocol
or an "advanced distance-vector" protocol
or a "hybrid" protocol
Configuring EIGRP on our network
------------------------------------------------------------------------------------------------------------------------------------
Corp(config)# router eigrp ?
<1-65535> Autonomous system number
Corp(config)#
router eigrp 10
R2(config-router)# network 10.0.0.0
after eigrp on R1- links from Corp to R1 are up
%DUAL-5-NBRCHANGE: IP-EIGRP 10: Neighbor 10.1.3.2 (Serial0/0/1) is up: new adjacency
%DUAL-5-NBRCHANGE: IP-EIGRP 10: Neighbor 10.1.2.2 (Serial0/0/0) is up: new adjacency
after eigrp on R2- link from Corp to R2 is up
%DUAL-5-NBRCHANGE: IP-EIGRP 10: Neighbor 10.1.4.2 (Serial0/1/0) is up: new adjacency
after eigrp on R3- link from Corp to R3 is up
%DUAL-5-NBRCHANGE: IP-EIGRP 10: Neighbor 10.1.5.2 (FastEthernet0/0) is up: new adjacency
------------------------------------------------------------------------------------------------------------------------------------
R1(config)# router eigrp 10
R1(config-router)# network 10.0.0.0
after eigrp on R1- link from R1 to Corp is up
%DUAL-5-NBRCHANGE: IP-EIGRP 10: Neighbor 10.1.3.1 (Serial0/0/1) is up: new adjacency
%DUAL-5-NBRCHANGE: IP-EIGRP 10: Neighbor 10.1.2.1 (Serial0/0/0) is up: new adjacency
R1(config-router)#
network 192.168.10.0
R1(config-router)# network 192.168.20.0
------------------------------------------------------------------------------------------------------------------------------------
R2(config)# router eigrp 10
R2(config-router)# network 10.0.0.0
after eigrp on R2- link from R2 to Corp is up
%DUAL-5-NBRCHANGE: IP-EIGRP 10: Neighbor 10.1.4.1 (Serial0/0/0) is up: new adjacency
R1(config-router)#
network 192.168.30.0
R1(config-router)# network 192.168.40.0
------------------------------------------------------------------------------------------------------------------------------------
R3(config)# router eigrp 10
R3(config-router)# network 10.0.0.0
after eigrp on R3- link from R3 to Corp is up
%DUAL-5-NBRCHANGE: IP-EIGRP 10: Neighbor 10.1.5.1 (FastEthernet0/0) is up: new adjacency
R1(config-router)#
network 172.16.0.0
------------------------------------------------------------------------------------------------------------------------------------
Corp# show ip route
Gateway of last resort is not set
Gateway of last resort is not set
10.0.0.0/8 is variably subnetted, 10 subnets, 2 masks
C 10.1.1.0/24 is directly connected, Vlan1
L 10.1.1.1/32 is directly connected, Vlan1
C 10.1.2.0/24 is directly connected, Serial0/0/0
L 10.1.2.1/32 is directly connected, Serial0/0/0
C 10.1.3.0/24 is directly connected, Serial0/0/1
L 10.1.3.1/32 is directly connected, Serial0/0/1
C 10.1.4.0/24 is directly connected, Serial0/1/0
L 10.1.4.1/32 is directly connected, Serial0/1/0
C 10.1.5.0/24 is directly connected, FastEthernet0/0
L 10.1.5.1/32 is directly connected, FastEthernet0/0
172.16.0.0/16 is variably subnetted, 2 subnets, 2 masks
R 172.16.0.0/16 [120/1] via 10.1.5.2, 00:00:17, FastEthernet0/0
D 172.16.10.0/24 [90/28160] via 10.1.5.2, 00:00:16, FastEthernet0/0
via R3
D 192.168.10.0/24 [90/2172416] via 10.1.2.2, 00:19:13, Serial0/0/0
[90/2172416] via 10.1.3.2, 00:19:13, Serial0/0/1
D 192.168.20.0/24 [90/2172416] via 10.1.3.2, 00:19:05, Serial0/0/1
[90/2172416] via 10.1.2.2, 00:19:05, Serial0/0/0
via R1
D 192.168.30.0/24 [90/2172416] via 10.1.4.2, 00:01:31, Serial0/1/0
D 192.168.40.0/24 [90/2172416] via 10.1.4.2, 00:01:08, Serial0/1/0
via R2
The "D" routes are for DUAL- Diffusing Update Algorithm, indicating they are EIGRP routes.
Note that we have RIP and EIGRP set currently
------------------------------------------------------------------------------------------------------------------------------------
R1# show ip route
Gateway of last resort is not set
10.0.0.0/8 is variably subnetted, 6 subnets, 2 masks
D 10.0.0.0/8 is a summary, 00:25:28, Null0
D 10.1.1.0/24 [90/27769856] via 10.1.2.1, 00:31:33, Serial0/0/0
[90/27769856] via 10.1.3.1, 00:31:30, Serial0/0/1
via Corp
C 10.1.2.0/24 is directly connected, Serial0/0/0
C 10.1.3.0/24 is directly connected, Serial0/0/1
D 10.1.4.0/24 [90/2681856] via 10.1.2.1, 00:31:33, Serial0/0/0
[90/2681856] via 10.1.3.1, 00:31:30, Serial0/0/1
D 10.1.5.0/24 [90/2172416] via 10.1.2.1, 00:31:33, Serial0/0/0
[90/2172416] via 10.1.3.1, 00:31:30, Serial0/0/1
via Corp
172.16.0.0/16 is variably subnetted, 2 subnets, 2 masks
R 172.16.0.0/16 [120/2] via 10.1.2.1, 00:00:07, Serial0/0/0
[120/2] via 10.1.3.1, 00:00:07, Serial0/0/1
D 172.16.10.0/24 [90/2172416] via 10.1.2.1, 00:06:31, Serial0/0/0
[90/2172416] via 10.1.3.1, 00:06:31, Serial0/0/1
via Corp
C 192.168.10.0/24 is directly connected, FastEthernet0/0
C 192.168.20.0/24 is directly connected, FastEthernet0/1
D 192.168.30.0/24 [90/2684416] via 10.1.3.1, 00:07:46, Serial0/0/1
[90/2684416] via 10.1.2.1, 00:07:46, Serial0/0/0
D 192.168.40.0/24 [90/2684416] via 10.1.2.1, 00:07:23, Serial0/0/0
[90/2684416] via 10.1.3.1, 00:07:23, Serial0/0/1
via Corp
------------------------------------------------------------------------------------------------------------------------------------
R2# show ip route
Gateway of last resort is not set
10.0.0.0/8 is variably subnetted, 6 subnets, 2 masks
D 10.0.0.0/8 is a summary, 00:13:09, Null0
D 10.1.1.0/24 [90/27769856] via 10.1.4.1, 00:36:53, Serial0/0/0
D 10.1.2.0/24 [90/2681856] via 10.1.4.1, 00:36:53, Serial0/0/0
D 10.1.3.0/24 [90/2681856] via 10.1.4.1, 00:36:53, Serial0/0/0
via Corp
C 10.1.4.0/24 is directly connected, Serial0/0/0
D 10.1.5.0/24 [90/2172416] via 10.1.4.1, 00:36:53, Serial0/0/0
via Corp
172.16.0.0/16 is variably subnetted, 2 subnets, 2 masks
R 172.16.0.0/16 [120/2] via 10.1.4.1, 00:00:23, Serial0/0/0
D 172.16.10.0/24 [90/2172416] via 10.1.4.1, 00:11:54, Serial0/0/0
via Corp
D 192.168.10.0/24 [90/2684416] via 10.1.4.1, 00:30:51, Serial0/0/0
D 192.168.20.0/24 [90/2684416] via 10.1.4.1, 00:30:43, Serial0/0/0
via Corp
C 192.168.30.0/24 is directly connected, FastEthernet0/0
C 192.168.40.0/24 is directly connected, FastEthernet0/1
------------------------------------------------------------------------------------------------------------------------------------
R3# show ip route
Gateway of last resort is 10.1.5.1 to network 0.0.0.0
10.0.0.0/8 is variably subnetted, 6 subnets, 2 masks
D 10.1.1.0/24 [90/25628160] via 10.1.5.1, 00:37:20, FastEthernet0/0
D 10.1.2.0/24 [90/2172416] via 10.1.5.1, 00:37:15, FastEthernet0/0
D 10.1.3.0/24 [90/2172416] via 10.1.5.1, 00:37:20, FastEthernet0/0
D 10.1.4.0/24 [90/2172416] via 10.1.5.1, 00:37:20, FastEthernet0/0
via Corp
C 10.1.5.0/24 is directly connected, FastEthernet0/0
L 10.1.5.2/32 is directly connected, FastEthernet0/0
172.16.0.0/16 is variably subnetted, 2 subnets, 2 masks
C 172.16.10.0/24 is directly connected, Dot11Radio0/0/0
L 172.16.10.1/32 is directly connected, Dot11Radio0/0/0
D 192.168.10.0/24 [90/2174976] via 10.1.5.1, 00:31:10, FastEthernet0/0
D 192.168.20.0/24 [90/2174976] via 10.1.5.1, 00:31:02, FastEthernet0/0
via Corp and R1
D 192.168.30.0/24 [90/2174976] via 10.1.5.1, 00:13:28, FastEthernet0/0
D 192.168.40.0/24 [90/2174976] via 10.1.5.1, 00:13:05, FastEthernet0/0
via Corp and R2
S* 0.0.0.0/0 [1/0] via 10.1.5.1
------------------------------------------------------------------------------------------------------------------------------------
turn off auto summary on each router
------------------------------------------------------------------------------------------------------------------------------------
Corp(config)# router eigrp 10
Corp(config-router)# no auto-summary
------------------------------------------------------------------------------------------------------------------------------------
R1(config)# router eigrp 10
R1(config-router)# no auto-summary
------------------------------------------------------------------------------------------------------------------------------------
R2(config)# router eigrp 10
R2(config-router)# no auto-summary
------------------------------------------------------------------------------------------------------------------------------------
R3(config)# router eigrp 10
R3(config-router)# no auto-summary
------------------------------------------------------------------------------------------------------------------------------------
compare Corp before and after auto summary turned off
------------------------------------------------------------------------------------------------------------------------------------
auto summary on
Corp# show ip route
Gateway of last resort is not set
10.0.0.0/8 is variably subnetted, 10 subnets, 2 masks
C 10.1.1.0/24 is directly connected, Vlan1
L 10.1.1.1/32 is directly connected, Vlan1
C 10.1.2.0/24 is directly connected, Serial0/0/0
L 10.1.2.1/32 is directly connected, Serial0/0/0
C 10.1.3.0/24 is directly connected, Serial0/0/1
L 10.1.3.1/32 is directly connected, Serial0/0/1
C 10.1.4.0/24 is directly connected, Serial0/1/0
L 10.1.4.1/32 is directly connected, Serial0/1/0
C 10.1.5.0/24 is directly connected, FastEthernet0/0
L 10.1.5.1/32 is directly connected, FastEthernet0/0
172.16.0.0/16 is variably subnetted, 2 subnets, 2 masks
R 172.16.0.0/16 [120/1] via 10.1.5.2, 00:00:17, FastEthernet0/0
D 172.16.10.0/24 [90/28160] via 10.1.5.2, 00:00:16, FastEthernet0/0
via R3
D 192.168.10.0/24 [90/2172416] via 10.1.2.2, 00:19:13, Serial0/0/0
[90/2172416] via 10.1.3.2, 00:19:13, Serial0/0/1
D 192.168.20.0/24 [90/2172416] via 10.1.3.2, 00:19:05, Serial0/0/1
[90/2172416] via 10.1.2.2, 00:19:05, Serial0/0/0
via R1
D 192.168.30.0/24 [90/2172416] via 10.1.4.2, 00:01:31, Serial0/1/0
D 192.168.40.0/24 [90/2172416] via 10.1.4.2, 00:01:08, Serial0/1/0
via R2
auto summary off
Corp# show ip route
Gateway of last resort is not set
10.0.0.0/8 is variably subnetted, 10 subnets, 2 masks
C 10.1.1.0/24 is directly connected, Vlan1
L 10.1.1.1/32 is directly connected, Vlan1
C 10.1.2.0/24 is directly connected, Serial0/0/0
L 10.1.2.1/32 is directly connected, Serial0/0/0
C 10.1.3.0/24 is directly connected, Serial0/0/1
L 10.1.3.1/32 is directly connected, Serial0/0/1
C 10.1.4.0/24 is directly connected, Serial0/1/0
L 10.1.4.1/32 is directly connected, Serial0/1/0
C 10.1.5.0/24 is directly connected, FastEthernet0/0
L 10.1.5.1/32 is directly connected, FastEthernet0/0
172.16.0.0/16 is variably subnetted, 2 subnets, 2 masks
R 172.16.0.0/16 [120/1] via 10.1.5.2, 00:00:12, FastEthernet0/0
D 172.16.10.0/24 [90/28160] via 10.1.5.2, 00:45:29, FastEthernet0/0
via R3
D 192.168.10.0/24 [90/2172416] via 10.1.2.2, 00:01:08, Serial0/0/0
[90/2172416] via 10.1.3.2, 00:01:08, Serial0/0/1
D 192.168.20.0/24 [90/2172416] via 10.1.2.2, 00:01:08, Serial0/0/0
[90/2172416] via 10.1.3.2, 00:01:08, Serial0/0/1
via R1
D 192.168.30.0/24 [90/2172416] via 10.1.4.2, 00:00:46, Serial0/1/0
D 192.168.40.0/24 [90/2172416] via 10.1.4.2, 00:00:46, Serial0/1/0
via R2
We are still seeing an auto summarized route- 172.16.0.0 coming from R3.
The book discusses enabling EIGRP auto summary on all four routers- nothing is said about disabling it within RIP or turning off RIP.
RIP auto summarizes by default. We cant get rid of this auto summary route while RIP is on.
Moving on...
VERIFYING EIGRP
several commands available to verify and troubleshoot
show ip route
show the entire routing table
show ip route eigrp
show only EIGRP entries in the routing table
show ip eigrp neighbors
show all EIGRP neigbors
show ip eigrp topology
show entries in the EIGRP topology table
show ip protocols
shows routing protocols configuration
debug eigrp packet
shows hello packets sent/received between adjacent routers
debug ip eigrp events
shows EIGRP changes and updates as they occur on your network
lets take a look at the state of our 4 routers. RIP and EIGRP are running on each.
Notice how this command is giving different outputs between the two different IOS versions
I'm also noticing that we have inconsistent auto-summarization settings- I was having trouble with this earlier. The book discusses
getting rid of the 172.16.0.0 summarized route in the EIGRP settings. I was not able to get rid of it, I think because RIP is still on, and RIP forces auto-summary
Part of the challenge here is that the book is strictly dealing with IOS 12.4
I will now make sure to turn auto summary off for both RIP and EIGRP on each of the four routers.
OK the part I am forgetting is that we are running RIP V2 which does not force auto-summary but runs it optionally, and we must turn it off to avoid auto summarization.
and lets see how the output looks now. This time I'll do show ip protocols and show ip route side by side for each router
EIGRP TERMINOLOGY
FEASIBLE DISTANCE (FD)
the best metric among all paths, including to the next hop neighbor. You will only see the route with the lowest FD appear in the routing table
The FD is calculated by adding the reported distance from the neighbor (AD) plus the metric to that neighbor
ADVERTISED DISTANCE (AD)
the metric of a remote network as reported by a neighbor, listed second in parenthesis in toplogy table
Neighbor Table
each router keeps state information about adjacent neighbors.. When a new neighbor is learned, the address and interface are recorded.
The neighbor table is stored in RAM.
Sequence numbres are used to match acks with update packets. The last squence number received from a neighbor is recorded so out of order packets can be detected
Topology Table
acted upon by DUAL Diffusing Update Alogorithm. Contains all destinations advertised by neighboring routers.
For each neighbor, the adversited distance, which comes only from that neighbor's routing table, is recorded
The feasible distance is also recorded.
Feasible Successor
a PATH whose advertised distance is less than the feasible distance of the current succesor, and is considered a backup route.
EIGRP keeps up to 16 feasible successors in the toplogy table.
The one with the best metric (The Successor) is copied and placed into the routing table
Successor
the best route to a remote network, used by EIGRP to forward traffic. It's backed up by a feasible successor, if one is available.
lets demo some more of the commands
VERIFYING EIGRP
several commands available to verify and troubleshoot
Build the network and configure interfaces
LabA(config)# int f0/0
LabA(config-if)# ip addr 172.16.10.1 255.255.255.0
LabA(config-if)# no shut
LabB(config)# int f0/0
LabB(config-if)# ip addr 172.16.10.2 255.255.255.0
LabB(config-if)# no shut
LabB(config-if)# int s0/0/0
LabB(config-if)# ip addr 172.16.20.1 255.255.255.0
LabB(config-if)# no shut
LabC(config)# int f0/0
LabC(config-if)# ip addr 172.16.30.1 255.255.255.0
LabC(config-if)# no shut
LabC(config-if)# int s0/0/0
LabC(config-if)# ip addr 172.16.20.2 255.255.255.0
LabC(config-if)# no shut
LabC(config-if)# int s0/0/1
LabC(config-if)# ip addr 172.16.40.1 255.255.255.0
LabC(config-if)# no shut
LabD(config)# int s0/0/0
LabD(config-if)# ip addr 172.16.40.2 255.255.255.0
LabD(config-if)# no shut
LabD(config-if)# int f0/0
LabD(config-if)# ip addr 172.16.50.1 255.255.255.0
LabD(config-if)# no shut
configure EIGRP on all 4 routers and observe results
LabA
LabA(config)# router eigrp 100
LabA(config-router)# net 172.16.0.0
LabA# show ip eigrp neighbors
LabA# show ip eigrp topology
LabA# show ip eigrp interfaces
no neighbors at this point since EIGRP is only active on this router. One successor AKA route, which is the connection out of this router.
But note that we have no information about what's on the other side of that link
LabB
LabB(config)# router eigrp 100
LabB(config-router)# net 172.16.0.0
LabB# show ip eigrp neighbors
LabB# show ip eigrp topology
LabB# show ip eigrp interfaces
We can see a neighbor at .1
We now have two paths out of this router. Left to neighbor. Exit at right is available as successor(route), but again we have no info about what is on the other side, since that router has no EIGRP yet (s0/0/0 has no peers, but is an EIGRP interface)
LabC
LabC(config)# router eigrp 100
LabC(config-router)# net 172.16.0.0
LabC# show ip eigrp neighbors
LabC# show ip eigrp toplogy
LabC# show ip eigrp interfaces
.1 router B interface is now a neighbor.
LabC topology shows the 3 direct connected networks AND the network on the other side of LabB since LabB is our EIGRP neighbor
3 eigrp interfaces:
Fa0/0 is ours at LabC- no peers bc there is no eigrp router on the other end
s0/0/0 is our interface out left to LabB which is an EIGRP peer
s0/0/1 is our interface out right which does not see an EIGRP peer but does put that net 172.16.40.0 in our topology
LabD
LabD(config)# router eigrp 100
LabD(config-router)# net 172.16.0.0
LabD# show ip eigrp neighbors
LabD# show ip eigrp topology
LabD# show ip eigrp interfaces
LabC to our left is now a neighbor at 172.16.40.1
toplogy shows a route out to the right (no router on that end)
a route to the left to LabC .40.0
the .10.0, .20.0, and .30.0 networks via info from LabC
2 eigrp interfaces-
fa0/0 out to the right
s0/0/0 out left to LabC
Time to remove EIGRP from all four routers to prepare for the OSPF lab next,
since EIGRP has a lower AD than OSPF
LabA(config)# no router eigrp 100
LabB(config)# no router eigrp 100
LabC(config)# no router eigrp 100
LabD(config)# no router eigrp 100
LabA
LabA(config)# router ospf 100
LabA(config-router)# net 172.16.10.1 0.0.0.0 area 0
LabA# show ip ospf neighbor
LabA# show ip ospf database
LabA# show ip ospf interface
we're including this router's interface 172.16.10.1 in our ospf area 0
fa0/0 now registers as an ospf interface
the ospf database includes data about this link only.... LabA is counting itself(10.1) as ADVERTISTING router?
the designated router is .1 LabA
LabB
LabB(config)# router ospf 101
LabB(config-router)# net 172.16.10.2 0.0.0.0 area 0
LabB(config-router)# net 172.16.20.1 0.0.0.0 area 0
LabB# show ip ospf neighbor
LabB# show ip ospf database
LabB# show ip ospf interface
We've include the two interfaces on this router in the OSPF area
and can now see Router A's interface 10.1 to the left as a neighbor in the area
the "OSPF Database" now shows two links 20.1(local) and 10.1(neighbor) as 'router link states'.
"ADV Router" means advertising router for the two links. The link address is used as the advertising router.
database shows "Net Link States" category with one entry- 172.16.10.1 which is the address of neighbor router to our left
we have two local OSPF interfaces- f0/0 and s0/0/0
LabC
LabC(config)# router ospf 102
LabC(config-router)# net 172.16.20.2 0.0.0.0 area 0
LabC(config-router)# net 172.16.30.1 0.0.0.0 area 0
LabC(config-router)# net 172.16.40.1 0.0.0.0 area 0
LabC# show ip ospf neighbor
LabC# show ip ospf database
LabC# show ip ospf interface
we include the three nets conneted to labC in the area.. 20.0, 30.0, and 40.0
link to our left, 20.1 is visible as "Neighbor"
OSPF Database-
Router Link States are
10.1(Router A)
20.1(Router B)
40.1(Router C)(This router)
Net Link States
10.1(Router A)... why does only Router A show here?
Reference- router link state vs net link state
Router Link States are type 1 LSAs. It lists all the routers in the area and the number of interfaces. 40.1 has 4 interfaces
Net Link States are the multi-access networks (Type 2 LSAs). The ADV (advertising router) is the DR.
LabD
LabD(config)# router ospf 103
LabD(config-router)# net 172.16.40.2 0.0.0.0 area 0
LabD(config-router)# net 172.16.50.1 0.0.0.0 area 0
LabD# show ip ospf neighbor
LabD# show ip ospf database
LabD# show ip ospf interface
observations
the OSPF databases now match across all 4 routers.
NOTE that this is a database of routers, identified by router ID. It is not a topology that lists routers AND routes, like in the "equivalent" eigrp command.show eigrp topology
----------------------------------------------------------------------------------
PAUSE- a tale of a misconfigured network
After a 9 month hiatus, I am reviewing this book and have made it back to Chapter 9. I'm studing this webpage, working thorough the OSPF configurations described above, and I get stuck on the concept of "link count" under "Router Link States" found in the output of show ip ospf database
The structure of the notes above is helpful, because I was tracking the state of each router BEFORE i made changes to the subsquent router. But just to be sure, today I decided to recreate the topology, then configure each router one at a time, noting the results as I went.
And I ran into some problems.
Here is the original topology:
And today's recreated toplogy:
After replicating the toplogy and programming the IP addresses on each router, I started on configurations, just like before:
LabA
LabA(config)# router ospf 100
LabA(config-router)# net 172.16.10.1 0.0.0.0 area 0
LabA# show ip ospf neighbor
LabA# show ip ospf database
LabA# show ip ospf interface
good so far.... On to LabB router
LabB
LabB(config)# router ospf 101
LabB(config-router)# net 172.16.10.2 0.0.0.0 area 0
LabB(config-router)# net 172.16.20.1 0.0.0.0 area 0
LabB# show ip ospf neighbor
LabB# show ip ospf database
LabB# show ip ospf interface
still looks good; same as before.... On to LabC router
LabC
LabC(config)# router ospf 102
LabC(config-router)# net 172.16.20.2 0.0.0.0 area 0
LabC(config-router)# net 172.16.30.1 0.0.0.0 area 0
LabC(config-router)# net 172.16.40.1 0.0.0.0 area 0
LabC# show ip ospf neighbor
And here is where I ran into trouble. The show ip ospf neighbor command returns nothing. How can that be?
After awhile I realized it is due to a misconfiguration in the topology.
For Lab C, I programmed the interfaces as follows:
LabC(config)# int f0/0
LabC(config-if)# ip addr 172.16.30.1 255.255.255.0
LabC(config-if)# no shut
LabC(config-if)# int s0/0/0
LabC(config-if)# ip addr 172.16.20.2 255.255.255.0
LabC(config-if)# no shut
LabC(config-if)# int s0/0/1
LabC(config-if)# ip addr 172.16.40.1 255.255.255.0
LabC(config-if)# no shut
and again here is the topology for that router:
but here is what it SHOULD HAVE looked like (as it did the first time I built it)
S0/0/0 and S0/0/1 are swapped. When I gave the IP 172.16.20.2 to s/0/0/0, thinking that was the interface on the left side which faces Lab B, I was actually giving 172.16.20.2 to the right side, facing LabC (which has no OSPF configs yet.)
Since the left side got got the IP intended for the right side which was 172.16.40.1
the inverse also occured-
the right side got the IP intended for the left which was 172.16.20.2
LabC left side should have been
s0/0/0 with 20.2
and LabC right side should have been
s0/0/1 with 40.1
The correct IPs were mapped to the correct interfaces. But the mistake happened before I even programmed them.
When I made the connections from LabB to LabC and from LabD to LabC, I plugged then into the wrong ports.
Interestingly.. not only is this causing OSPF to not see B as a neighbor from C.. but B and C cannot ping eachother either.
@B the config is 172.16.20.1/24 @ S0/0/0
@C the config is 172.16.40.1/24 @ S/0/0/1
meaning they are not even on the same network! But the system is not throwing any errors or bringing it to my attention. It just fails to connect.
To correct the issue, I simply deleted those two links and re-created them. Worth noting, I used the auto select cable here, which does not ask which interface you want to use when attaching. Earlier I must have plugged the right side first, and auto select plugged into 0/0/0.
This time I plugged into left side first.
Now LabC OSPF data is reading out correctly...
LabC
LabC(config)# router ospf 102
LabC(config-router)# net 172.16.20.2 0.0.0.0 area 0
LabC(config-router)# net 172.16.30.1 0.0.0.0 area 0
LabC(config-router)# net 172.16.40.1 0.0.0.0 area 0
LabC# show ip ospf neighbor
LabC# show ip ospf database
LabC# show ip ospf interface
Which brings me to the original reason I re-created this topology... I was confused about the LINK COUNTS here:
The steps of recreating the lab were helpful, but this link answered the question:
Here is the output of each router's command show ip ospf interface as they are set up one at a time.
LabA - No OSPF at B, C, or D yet
LabB - No OSPF at C or D yet
the 20.2 interface on this router has 2 ospf links.
The left-facing out to RA, a crossover cable
The right-facing out to RC, a serial cable.
If the solution I found is correct, why is this serial link not being counted twice? The solution (I think) is revealed after the configuration of the next router...
LabC - No OSPF at D yet
NOW we can see that the 20.1 link, which is the right-facing interface on LabB.. aka the router ID..
has THREE OSPF links.
Nothing changed on the left side of B. But on the right side, we now have an active OSPF router at the other end of the link. This leads me to believe that the forum post was correct that 'serial links are counted twice', but, more specifically, BOTH ENDS of the serial(PPP) link are counted... IF there is an OSPF router on each end.
This is backed up by the fact that LabC, OSPF id 40.1, has four OSPF links. The top-facing link to the 30 network DOES count.. even though it has no OSPF router on the other end. It counts because it's not a serial link.
The requirement of having an OSPF router on the other end for an interface to count here, only applies to serial links. And pertains to BOTH ends of the link being counted.
In LabC's case, we have one serial at left, being counted twice. One ethernet at top, being counted once. And one serial at right only being counted once because LabD is not active with OSPF yet.
If this is correct, then we should see Lab C's 40.1 count go to 5 after LabD is set for OSPF....
LabD - all 4 routers have OSPF
and back to LabC.....
Looks good! The link count for each router makes sense if you count the serial interfaces twice (one for each end).
the OSPF databases now match across all 4 routers.
NOTE that this is a database of routers, identified by router ID. It is not a topology that lists routers AND routes, like in the "equivalent" eigrp command show eigrp topology
Note that the .30 network is NOT represented here.
LabA# show ip ospf database
LabB# show ip ospf database
LabC# show ip ospf database
LabD# show ip ospf database
Below is our routing tables with OSPF data. We do see the .30 network here.
Everyone can reach it:
LabA via LabB's 10.2
LabB via LabC's 20.2
LabC via direct connection
LabD via LabC's 40.1
LabA# show ip route
LabB# show ip route
LabC# show ip route
LabD# show ip route
moving on.......
show the entire routing table
show ip route eigrp
show only EIGRP entries in the routing table
show ip eigrp neighbors
show all EIGRP neigbors
show ip eigrp topology
show entries in the EIGRP topology table
show ip protocols
shows routing protocols configuration
debug eigrp packet
shows hello packets sent/received between adjacent routers
debug ip eigrp events
shows EIGRP changes and updates as they occur on your network
lets take a look at the state of our 4 routers. RIP and EIGRP are running on each.
Notice how this command is giving different outputs between the two different IOS versions
IOS 15.1
Corp# show ip protocols
Corp# show ip protocols
Routing Protocol is "eigrp 10 "
Outgoing update filter list for all interfaces is not set
Incoming update filter list for all interfaces is not set
Default networks flagged in outgoing updates
Default networks accepted from incoming updates
Redistributing: eigrp 10
EIGRP-IPv4 Protocol for AS(10)
Metric weight K1=1, K2=0, K3=1, K4=0, K5=0
NSF-aware route hold timer is 240
Router-ID: 10.1.1.1
Topology : 0 (base)
Active Timer: 3 min
Distance: internal 90 external 170
Maximum path: 4
Maximum hopcount 100
Maximum metric variance 1
Automatic Summarization: disabled
Automatic address summarization:
Maximum path: 4
Routing for Networks:
10.0.0.0
Routing Information Sources:
Gateway Distance Last Update
10.1.5.2 90 0
10.1.3.2 90 6464
10.1.2.2 90 6795
10.1.4.2 90 7955
Distance: internal 90 external 170
Routing Protocol is "rip"
Sending updates every 30 seconds, next due in 10 seconds
Invalid after 180 seconds, hold down 180, flushed after 240
Outgoing update filter list for all interfaces is not set
Incoming update filter list for all interfaces is not set
Redistributing: rip
Default version control: send version 2, receive 2
Interface Send Recv Triggered RIP Key-chain
Vlan1 2 2
FastEthernet0/0 2 2
Serial0/1/0 2 2
Serial0/0/1 2 2
Serial0/0/0 2 2
Automatic network summarization is in effect
Maximum path: 4
Routing for Networks:
10.0.0.0
Passive Interface(s):
Routing Information Sources:
Gateway Distance Last Update
10.1.5.2 120 00:00:12
10.1.3.2 120 00:00:16
10.1.2.2 120 00:00:16
10.1.4.2 120 00:00:13
Distance: (default is 120)
IOS 12.4
R1# show ip protocols
R1# show ip protocols
Routing Protocol is "eigrp 10 "
Outgoing update filter list for all interfaces is not set
Incoming update filter list for all interfaces is not set
Default networks flagged in outgoing updates
Default networks accepted from incoming updates
EIGRP metric weight K1=1, K2=0, K3=1, K4=0, K5=0
EIGRP maximum hopcount 100
EIGRP maximum metric variance 1
Redistributing: eigrp 10
Automatic network summarization is not in effect
Maximum path: 4
Routing for Networks:
10.0.0.0
192.168.10.0
192.168.20.0
Routing Information Sources:
Gateway Distance Last Update
10.1.3.1 90 6465
10.1.2.1 90 6794
Distance: internal 90 external 170
Routing Protocol is "rip"
Sending updates every 30 seconds, next due in 21 seconds
Invalid after 180 seconds, hold down 180, flushed after 240
Outgoing update filter list for all interfaces is not set
Incoming update filter list for all interfaces is not set
Redistributing: rip
Default version control: send version 2, receive 2
Interface Send Recv Triggered RIP Key-chain
FastEthernet0/0 2 2
FastEthernet0/1 2 2
Serial0/0/0 2 2
Serial0/0/1 2 2
Automatic network summarization is not in effect
Maximum path: 4
Routing for Networks:
10.0.0.0
192.168.10.0
192.168.20.0
Passive Interface(s):
Routing Information Sources:
Gateway Distance Last Update
10.1.3.1 120 00:00:06
10.1.2.1 120 00:00:06
Distance: (default is 120)
IOS 12.4
R2# show ip protocols
R2# show ip protocols
Routing Protocol is "eigrp 10 "
Outgoing update filter list for all interfaces is not set
Incoming update filter list for all interfaces is not set
Default networks flagged in outgoing updates
Default networks accepted from incoming updates
EIGRP metric weight K1=1, K2=0, K3=1, K4=0, K5=0
EIGRP maximum hopcount 100
EIGRP maximum metric variance 1
Redistributing: eigrp 10
Automatic network summarization is not in effect
Maximum path: 4
Routing for Networks:
10.0.0.0
192.168.30.0
192.168.40.0
Routing Information Sources:
Gateway Distance Last Update
10.1.4.1 90 7955
Distance: internal 90 external 170
Routing Protocol is "rip"
Sending updates every 30 seconds, next due in 11 seconds
Invalid after 180 seconds, hold down 180, flushed after 240
Outgoing update filter list for all interfaces is not set
Incoming update filter list for all interfaces is not set
Redistributing: rip
Default version control: send version 2, receive 2
Interface Send Recv Triggered RIP Key-chain
FastEthernet0/0 2 2
FastEthernet0/1 2 2
Serial0/0/0 2 2
Automatic network summarization is in effect
Maximum path: 4
Routing for Networks:
10.0.0.0
192.168.30.0
192.168.40.0
Passive Interface(s):
Routing Information Sources:
Gateway Distance Last Update
10.1.4.1 120 00:00:20
Distance: (default is 120)
IOS 15.1
R3# show ip protocols
R3# show ip protocols
Routing Protocol is "eigrp 10 "
Outgoing update filter list for all interfaces is not set
Incoming update filter list for all interfaces is not set
Default networks flagged in outgoing updates
Default networks accepted from incoming updates
Redistributing: eigrp 10
EIGRP-IPv4 Protocol for AS(10)
Metric weight K1=1, K2=0, K3=1, K4=0, K5=0
NSF-aware route hold timer is 240
Router-ID: 10.1.5.2
Topology : 0 (base)
Active Timer: 3 min
Distance: internal 90 external 170
Maximum path: 4
Maximum hopcount 100
Maximum metric variance 1
Automatic Summarization: disabled
Automatic address summarization:
Maximum path: 4
Routing for Networks:
10.0.0.0
172.16.0.0
Routing Information Sources:
Gateway Distance Last Update
10.1.5.1 90 0
Distance: internal 90 external 170
Routing Protocol is "rip"
Sending updates every 30 seconds, next due in 27 seconds
Invalid after 180 seconds, hold down 180, flushed after 240
Outgoing update filter list for all interfaces is not set
Incoming update filter list for all interfaces is not set
Redistributing: rip
Default version control: send version 2, receive 2
Interface Send Recv Triggered RIP Key-chain
Dot11Radio0/0/0 2 2
FastEthernet0/0 2 2
Automatic network summarization is not in effect
Maximum path: 4
Routing for Networks:
10.0.0.0
172.16.0.0
Passive Interface(s):
Routing Information Sources:
Gateway Distance Last Update
10.1.5.1 120 00:00:02
Distance: (default is 120)
I'm also noticing that we have inconsistent auto-summarization settings- I was having trouble with this earlier. The book discusses
getting rid of the 172.16.0.0 summarized route in the EIGRP settings. I was not able to get rid of it, I think because RIP is still on, and RIP forces auto-summary
Part of the challenge here is that the book is strictly dealing with IOS 12.4
I will now make sure to turn auto summary off for both RIP and EIGRP on each of the four routers.
OK the part I am forgetting is that we are running RIP V2 which does not force auto-summary but runs it optionally, and we must turn it off to avoid auto summarization.
Corp(config)#
router rip
Corp(config-router)# no auto-summary
Corp(config-router)# router eigrp 10
Corp(config-router)# no auto-summary
Corp(config-router)# no auto-summary
Corp(config-router)# router eigrp 10
Corp(config-router)# no auto-summary
R1(config)#
router rip
R1(config-router)# no auto-summary
R1(config-router)# router eigrp 10
R1(config-router)# no auto-summary
R1(config-router)# no auto-summary
R1(config-router)# router eigrp 10
R1(config-router)# no auto-summary
R1(config)#
router rip
R1(config-router)# no auto-summary
R1(config-router)# router eigrp 10
R2(config-router)# no auto-summary
R1(config-router)# no auto-summary
R1(config-router)# router eigrp 10
R2(config-router)# no auto-summary
R3(config)#
router rip
R3(config-router)# no auto-summary
R3(config-router)# router eigrp 10
R3(config-router)# no auto-summary
R3(config-router)# no auto-summary
R3(config-router)# router eigrp 10
R3(config-router)# no auto-summary
and lets see how the output looks now. This time I'll do show ip protocols and show ip route side by side for each router
IOS 15.1
Corp# show ip protocols
Corp# show ip protocols
Routing Protocol is "eigrp 10 "
Outgoing update filter list for all interfaces is not set
Incoming update filter list for all interfaces is not set
Default networks flagged in outgoing updates
Default networks accepted from incoming updates
Redistributing: eigrp 10
EIGRP-IPv4 Protocol for AS(10)
Metric weight K1=1, K2=0, K3=1, K4=0, K5=0
NSF-aware route hold timer is 240
Router-ID: 10.1.1.1
Topology : 0 (base)
Active Timer: 3 min
Distance: internal 90 external 170
Maximum path: 4
Maximum hopcount 100
Maximum metric variance 1
Automatic Summarization: disabled
Automatic address summarization:
Maximum path: 4
Routing for Networks:
10.0.0.0
Routing Information Sources:
Gateway Distance Last Update
10.1.5.2 90 0
10.1.3.2 90 6464
10.1.2.2 90 6795
10.1.4.2 90 7955
Distance: internal 90 external 170
Routing Protocol is "rip" doesnt necessarily mean RIPv1
Sending updates every 30 seconds, next due in 3 seconds
Invalid after 180 seconds, hold down 180, flushed after 240
Outgoing update filter list for all interfaces is not set
Incoming update filter list for all interfaces is not set
Redistributing: rip
Default version control: send version 2, receive 2 RIPv2 is specified
Interface Send Recv Triggered RIP Key-chain
Vlan1 2 2
FastEthernet0/0 2 2
Serial0/1/0 2 2
Serial0/0/1 2 2
Serial0/0/0 2 2
Automatic network summarization is not in effect
Maximum path: 4
Routing for Networks:
10.0.0.0
Passive Interface(s):
Routing Information Sources:
Gateway Distance Last Update
10.1.5.2 120 00:00:02
10.1.3.2 120 00:00:21
10.1.2.2 120 00:00:21
10.1.4.2 120 00:00:04
Distance: (default is 120)
IOS 15.1
Corp# show ip route
Corp# show ip route
Gateway of last resort is not set
10.0.0.0/8 is variably subnetted, 10 subnets, 2 masks
C 10.1.1.0/24 is directly connected, Vlan1
L 10.1.1.1/32 is directly connected, Vlan1
C 10.1.2.0/24 is directly connected, Serial0/0/0
L 10.1.2.1/32 is directly connected, Serial0/0/0
C 10.1.3.0/24 is directly connected, Serial0/0/1
L 10.1.3.1/32 is directly connected, Serial0/0/1
C 10.1.4.0/24 is directly connected, Serial0/1/0
L 10.1.4.1/32 is directly connected, Serial0/1/0
C 10.1.5.0/24 is directly connected, FastEthernet0/0
L 10.1.5.1/32 is directly connected, FastEthernet0/0
172.16.0.0/24 is subnetted, 1 subnets
D 172.16.10.0/24 [90/28160] via 10.1.5.2, 00:57:25, FastEthernet0/0
D 192.168.10.0/24 [90/2172416] via 10.1.3.2, 00:57:20, Serial0/0/1
[90/2172416] via 10.1.2.2, 00:57:20, Serial0/0/0
D 192.168.20.0/24 [90/2172416] via 10.1.3.2, 00:57:20, Serial0/0/1
[90/2172416] via 10.1.2.2, 00:57:20, Serial0/0/0
D 192.168.30.0/24 [90/2172416] via 10.1.4.2, 00:57:19, Serial0/1/0
D 192.168.40.0/24 [90/2172416] via 10.1.4.2, 00:57:19, Serial0/1/0
IOS 12.4
R1# show ip protocols
R1# show ip protocols
Routing Protocol is "eigrp 10 "
Outgoing update filter list for all interfaces is not set
Incoming update filter list for all interfaces is not set
Default networks flagged in outgoing updates
Default networks accepted from incoming updates
EIGRP metric weight K1=1, K2=0, K3=1, K4=0, K5=0
EIGRP maximum hopcount 100
EIGRP maximum metric variance 1
Redistributing: eigrp 10
Automatic network summarization is not in effect
Maximum path: 4
Routing for Networks:
10.0.0.0
192.168.10.0
192.168.20.0
Routing Information Sources:
Gateway Distance Last Update
10.1.3.1 90 6465
10.1.2.1 90 6794
Distance: internal 90 external 170
Routing Protocol is "rip"
Sending updates every 30 seconds, next due in 26 seconds
Invalid after 180 seconds, hold down 180, flushed after 240
Outgoing update filter list for all interfaces is not set
Incoming update filter list for all interfaces is not set
Redistributing: rip
Default version control: send version 2, receive 2
Interface Send Recv Triggered RIP Key-chain
FastEthernet0/0 2 2
FastEthernet0/1 2 2
Serial0/0/0 2 2
Serial0/0/1 2 2
Automatic network summarization is not in effect
Maximum path: 4
Routing for Networks:
10.0.0.0
192.168.10.0
192.168.20.0
Passive Interface(s):
Routing Information Sources:
Gateway Distance Last Update
10.1.3.1 120 00:00:03
10.1.2.1 120 00:00:03
Distance: (default is 120)
IOS 12.4
R1# show ip route
and on Corp, those networks were added to the interfaces with a /24 mask.
so even though our EIGRP config doesnt specifically include /24 networks.. we told it to include anything with a 10.x.x.x
Corp is advertising to R1 our /24 network interfaces that have a 10 in the first octet, EXCEPT the two which are directly connected to R1
10.1.1.0
10.1.4.0
10.1.5.0
are assumed to be the subnets based on the info we configured, which was 10.1.4.1/24 on corp, and 10.1.4.2/24 on r2 s0/0/0
nowhere in this configuration, have we entered the 10.1.4.0 network.
EIGRP is figuring it out based on the /24 mask we gave when assiging he IPs to the interfaces
R1# show ip route
Gateway of last resort is not set
10.0.0.0/24 is subnetted, 5 subnets
D 10.1.1.0 [90/27769856] via 10.1.3.1, 00:54:47, Serial0/0/1
[90/27769856] via 10.1.2.1, 00:54:47, Serial0/0/0
C 10.1.2.0 is directly connected, Serial0/0/0
C 10.1.3.0 is directly connected, Serial0/0/1
D 10.1.4.0 [90/2681856] via 10.1.3.1, 00:54:47, Serial0/0/1
[90/2681856] via 10.1.2.1, 00:54:47, Serial0/0/0
D 10.1.5.0 [90/2172416] via 10.1.3.1, 00:54:47, Serial0/0/1
[90/2172416] via 10.1.2.1, 00:54:47, Serial0/0/0
172.16.0.0/24 is subnetted, 1 subnets
D 172.16.10.0 [90/2172416] via 10.1.3.1, 00:54:47, Serial0/0/1
[90/2172416] via 10.1.2.1, 00:54:47, Serial0/0/0
C 192.168.10.0/24 is directly connected, FastEthernet0/0
C 192.168.20.0/24 is directly connected, FastEthernet0/1
D 192.168.30.0/24 [90/2684416] via 10.1.3.1, 00:54:46, Serial0/0/1
[90/2684416] via 10.1.2.1, 00:54:46, Serial0/0/0
D 192.168.40.0/24 [90/2684416] via 10.1.3.1, 00:54:46, Serial0/0/1
[90/2684416] via 10.1.2.1, 00:54:46, Serial0/0/0
note that the DUAL routes being advertised from the 10.0.0.0 networks are all specific to the third octet.. that's because we are reading those routes
from their source, aka the router which they are directly connected to, Corp.
and on Corp, those networks were added to the interfaces with a /24 mask.
so even though our EIGRP config doesnt specifically include /24 networks.. we told it to include anything with a 10.x.x.x
Corp is advertising to R1 our /24 network interfaces that have a 10 in the first octet, EXCEPT the two which are directly connected to R1
10.1.1.0
10.1.4.0
10.1.5.0
are assumed to be the subnets based on the info we configured, which was 10.1.4.1/24 on corp, and 10.1.4.2/24 on r2 s0/0/0
nowhere in this configuration, have we entered the 10.1.4.0 network.
EIGRP is figuring it out based on the /24 mask we gave when assiging he IPs to the interfaces
IOS 12.4
R2# show ip protocols
R2# show ip protocols
Routing Protocol is "eigrp 10 "
Outgoing update filter list for all interfaces is not set
Incoming update filter list for all interfaces is not set
Default networks flagged in outgoing updates
Default networks accepted from incoming updates
EIGRP metric weight K1=1, K2=0, K3=1, K4=0, K5=0
EIGRP maximum hopcount 100
EIGRP maximum metric variance 1
Redistributing: eigrp 10
Automatic network summarization is not in effect
Maximum path: 4
Routing for Networks:
10.0.0.0
192.168.30.0
192.168.40.0
Routing Information Sources:
Gateway Distance Last Update
10.1.4.1 90 7955
Distance: internal 90 external 170
Routing Protocol is "rip"
Sending updates every 30 seconds, next due in 18 seconds
Invalid after 180 seconds, hold down 180, flushed after 240
Outgoing update filter list for all interfaces is not set
Incoming update filter list for all interfaces is not set
Redistributing: rip
Default version control: send version 2, receive 2
Interface Send Recv Triggered RIP Key-chain
FastEthernet0/0 2 2
FastEthernet0/1 2 2
Serial0/0/0 2 2
Automatic network summarization is not in effect
Maximum path: 4
Routing for Networks:
10.0.0.0
192.168.30.0
192.168.40.0
Passive Interface(s):
Routing Information Sources:
Gateway Distance Last Update
10.1.4.1 120 00:00:07
Distance: (default is 120)
IOS 12.4
R2# show ip route
R2# show ip route
Gateway of last resort is not set
10.0.0.0/24 is subnetted, 5 subnets
D 10.1.1.0 [90/27769856] via 10.1.4.1, 00:59:10, Serial0/0/0
D 10.1.2.0 [90/2681856] via 10.1.4.1, 00:59:10, Serial0/0/0
D 10.1.3.0 [90/2681856] via 10.1.4.1, 00:59:10, Serial0/0/0
C 10.1.4.0 is directly connected, Serial0/0/0
D 10.1.5.0 [90/2172416] via 10.1.4.1, 00:59:10, Serial0/0/0
172.16.0.0/24 is subnetted, 1 subnets
D 172.16.10.0 [90/2172416] via 10.1.4.1, 00:59:10, Serial0/0/0
D 192.168.10.0/24 [90/2684416] via 10.1.4.1, 00:59:10, Serial0/0/0
D 192.168.20.0/24 [90/2684416] via 10.1.4.1, 00:59:10, Serial0/0/0
C 192.168.30.0/24 is directly connected, FastEthernet0/0
C 192.168.40.0/24 is directly connected, FastEthernet0/1
IOS 15.1
R3# show ip protocols
R3# show ip protocols
Routing Protocol is "eigrp 10 "
Outgoing update filter list for all interfaces is not set
Incoming update filter list for all interfaces is not set
Default networks flagged in outgoing updates
Default networks accepted from incoming updates
Redistributing: eigrp 10
EIGRP-IPv4 Protocol for AS(10)
Metric weight K1=1, K2=0, K3=1, K4=0, K5=0
NSF-aware route hold timer is 240
Router-ID: 10.1.5.2
Topology : 0 (base)
Active Timer: 3 min
Distance: internal 90 external 170
Maximum path: 4
Maximum hopcount 100
Maximum metric variance 1
Automatic Summarization: disabled
Automatic address summarization:
Maximum path: 4
Routing for Networks:
10.0.0.0
172.16.0.0
Routing Information Sources:
Gateway Distance Last Update
10.1.5.1 90 0
Distance: internal 90 external 170
Routing Protocol is "rip"
Sending updates every 30 seconds, next due in 15 seconds
Invalid after 180 seconds, hold down 180, flushed after 240
Outgoing update filter list for all interfaces is not set
Incoming update filter list for all interfaces is not set
Redistributing: rip
Default version control: send version 2, receive 2
Interface Send Recv Triggered RIP Key-chain
Dot11Radio0/0/0 2 2
FastEthernet0/0 2 2
Automatic network summarization is not in effect
Maximum path: 4
Routing for Networks:
10.0.0.0
172.16.0.0
Passive Interface(s):
Routing Information Sources:
Gateway Distance Last Update
10.1.5.1 120 00:00:14
Distance: (default is 120)
IOS 15.1
R3# show ip route
Since this is a 15.1 router, we always get a "L" local route when we have a "C" connected route. In R3's case, the 172.16.10.0 network is directly connected. The interface which connects it, 172.16.10.1, counts as a "local" route. This is NOT the case on the 12.4 routers.
looking to the left, our protocol output tells us two key facts for both EIGRP and RIP:
Routing for networks:
10.0.0.0
172.16.0.0
R3 is responsible for *sending* data about these two networks to our other EIGRP routers...
"I'm R3 and I can connect you to networks on the R3 router or networks on the Corp router"
Notice how the 192 networks arent listed. R3 isnt connected to a 192 network directly, nor is it connected to a neighbor who is directly connected.
If I, as a client, am sending data to a 192 network from the 172 network, I will start at R3. Since R3 is receiving routes for the 192 networks via Corp, I will be able to reach a 192 network via Corp. My connection to corp will happen VIA a "10.0.0.0" route.
R3 is technically only routing for 172 and 10 networks. Beyond that, it could potentially connect to many other different networks. But in terms of the R3 routing table, all it can offer is a path out to the 172 network or the 10 network
Routing information sources:
10.1.5.1
In this case I can see that R3 is receiving routing data from one interface only, and that is it's link to Corp. Some of the data we are receiving from Corp actually originates at other routers, but we cant see that here; the data comes to us from Corp, and that is all we know
R3# show ip route
Gateway of last resort is 10.1.5.1 to network 0.0.0.0
10.0.0.0/8 is variably subnetted, 6 subnets, 2 masks
D 10.1.1.0/24 [90/25628160] via 10.1.5.1, 00:59:52, FastEthernet0/0
D 10.1.2.0/24 [90/2172416] via 10.1.5.1, 00:59:47, FastEthernet0/0
D 10.1.3.0/24 [90/2172416] via 10.1.5.1, 00:59:52, FastEthernet0/0
D 10.1.4.0/24 [90/2172416] via 10.1.5.1, 00:59:52, FastEthernet0/0
C 10.1.5.0/24 is directly connected, FastEthernet0/0
L 10.1.5.2/32 is directly connected, FastEthernet0/0
172.16.0.0/16 is variably subnetted, 2 subnets, 2 masks
C 172.16.10.0/24 is directly connected, Dot11Radio0/0/0
L 172.16.10.1/32 is directly connected, Dot11Radio0/0/0
D 192.168.10.0/24 [90/2174976] via 10.1.5.1, 00:59:47, FastEthernet0/0
D 192.168.20.0/24 [90/2174976] via 10.1.5.1, 00:59:47, FastEthernet0/0
D 192.168.30.0/24 [90/2174976] via 10.1.5.1, 00:59:46, FastEthernet0/0
D 192.168.40.0/24 [90/2174976] via 10.1.5.1, 00:59:46, FastEthernet0/0
S* 0.0.0.0/0 [1/0] via 10.1.5.1
Observations:
Since this is a 15.1 router, we always get a "L" local route when we have a "C" connected route. In R3's case, the 172.16.10.0 network is directly connected. The interface which connects it, 172.16.10.1, counts as a "local" route. This is NOT the case on the 12.4 routers.
looking to the left, our protocol output tells us two key facts for both EIGRP and RIP:
Routing for networks:
10.0.0.0
172.16.0.0
R3 is responsible for *sending* data about these two networks to our other EIGRP routers...
"I'm R3 and I can connect you to networks on the R3 router or networks on the Corp router"
Notice how the 192 networks arent listed. R3 isnt connected to a 192 network directly, nor is it connected to a neighbor who is directly connected.
If I, as a client, am sending data to a 192 network from the 172 network, I will start at R3. Since R3 is receiving routes for the 192 networks via Corp, I will be able to reach a 192 network via Corp. My connection to corp will happen VIA a "10.0.0.0" route.
R3 is technically only routing for 172 and 10 networks. Beyond that, it could potentially connect to many other different networks. But in terms of the R3 routing table, all it can offer is a path out to the 172 network or the 10 network
Routing information sources:
10.1.5.1
In this case I can see that R3 is receiving routing data from one interface only, and that is it's link to Corp. Some of the data we are receiving from Corp actually originates at other routers, but we cant see that here; the data comes to us from Corp, and that is all we know
EIGRP TERMINOLOGY
FEASIBLE DISTANCE (FD)
the best metric among all paths, including to the next hop neighbor. You will only see the route with the lowest FD appear in the routing table
The FD is calculated by adding the reported distance from the neighbor (AD) plus the metric to that neighbor
ADVERTISED DISTANCE (AD)
the metric of a remote network as reported by a neighbor, listed second in parenthesis in toplogy table
P 192.168.20.0/24, 2 successors, FD is 2172416
via 10.1.3.2 (2172416/28160), Serial0/0/1
feasible / advertised
Neighbor Table
each router keeps state information about adjacent neighbors.. When a new neighbor is learned, the address and interface are recorded.
The neighbor table is stored in RAM.
Sequence numbres are used to match acks with update packets. The last squence number received from a neighbor is recorded so out of order packets can be detected
Topology Table
acted upon by DUAL Diffusing Update Alogorithm. Contains all destinations advertised by neighboring routers.
For each neighbor, the adversited distance, which comes only from that neighbor's routing table, is recorded
The feasible distance is also recorded.
Feasible Successor
a PATH whose advertised distance is less than the feasible distance of the current succesor, and is considered a backup route.
EIGRP keeps up to 16 feasible successors in the toplogy table.
The one with the best metric (The Successor) is copied and placed into the routing table
Successor
the best route to a remote network, used by EIGRP to forward traffic. It's backed up by a feasible successor, if one is available.
lets demo some more of the commands
VERIFYING EIGRP
several commands available to verify and troubleshoot
show ip route
show the entire routing table
show ip route eigrp
show only EIGRP entries in the routing table
show ip eigrp neighbors
show all EIGRP neigbors
show ip eigrp topology
show entries in the EIGRP topology table
show ip protocols
shows routing protocols configuration
debug eigrp packet
shows hello packets sent/received between adjacent routers
debug ip eigrp events
shows EIGRP changes and updates as they occur on your network
Corp# show ip eigrp ?
Corp# show ip eigrp topology
the "P" preceding each entry is for PASSIVE
these routes are in a passive state, which is good
if they move to an ACTIVE state, it means the have lost their path in the network and looking for a replacement.
Each entry also shows the FEASIBLE DISTANCE, the next hop address, and the local egress interface
Corp# show ip eigrp neighbors
fields:
H - the order in which the neighbors were discovered
hold - how long the router will wait for a hello packet
uptime - how long the neigborship has been established
SRTT - smooth round trip timer - the time it takes for a round trip from this router, to neighbor, and back.
SRTT is used to determine how long to wait for a MULTICAST reply.
if a reply isnt received in time, the router switches to UNICASTS
RTO - Retransmission Time Out- is the time EIGRP waits before retransmitting a packet from the retransmission queue
Q - indicates wheter there are oustanding messages in the queue
Seq - indicates the sequence number of the last update from that neighbor. This is used to maintain syncrhonization and avoid duplicate or out-of-sequence processing of messages
Corp# show ip route eigrp
Corp#
show ip eigrp interfaces
Corp# show ip protocols
corp# debug eigrp packet
break into two columns for readability
Observations:
There doesnt appear to be a pattern in the order each router is addressed, except that the TO's and FROM"s are grouped together
The TO messages dont show the destination IP, only the egress local interface
The FROM messages do show the remote IP, as well as the local ingress interface
Now some videos. To reinforce EIGRP concepts, and lead into OSPF
OSPF - OPEN SHORTEST PATH FIRST
Before enabling OSPF, we'll turn off RIP and EIGRP on all four routers.
Device(config)# no router eigrp 10
Device(config)# no router rip
The OSPF configs for the local egress ip address
Corp(config)# router ospf 132
Corp(config)# network 10.1.0.0 0.0.255.255 area 0
R1(config)# router ospf 1
R1(config)# network 10.1.0.0 0.0.255.255 area 0
R1(config)# network 192.168.0.0 0.0.255.255 area 0
R2(config)# router ospf 45678
R2(config)# network 10.0.0.0 0.0.0.255 area 0
R2(config)# network 192.168.30.1 0.0.0.0 area 0
R2(config)# network 192.168.40.1 0.0.0.0 area 0
these are not network id's, they are HOST id's of the specific interfaces, which are EGRESS interfaces on the router we are configuring
R3(config)# router ospf 1
R2(config)# network 10.1.5.2 0.0.0.255 area 0
R2(config)# network 172.16.10.0 0.0.0.255 area 0
Wildcard Masks
these notes are not intended to be a precise explanation of wlidcard masking, but rather a look into my thought process as I am learning the concept.
resources:
traceroute blog examples
routerjockey blog examples
subnetonline wildcard calculator
show the entire routing table
show ip route eigrp
show only EIGRP entries in the routing table
show ip eigrp neighbors
show all EIGRP neigbors
show ip eigrp topology
show entries in the EIGRP topology table
show ip protocols
shows routing protocols configuration
debug eigrp packet
shows hello packets sent/received between adjacent routers
debug ip eigrp events
shows EIGRP changes and updates as they occur on your network
Corp# show ip eigrp ?
interfaces IP-EIGRP interfaces
neighbors IP-EIGRP neighbors
topology IP-EIGRP Topology Table
traffic IP-EIGRP Traffic Statistics
Corp# show ip eigrp topology
IP-EIGRP Topology Table for AS 10/ID(10.1.5.1)
Codes: P - Passive, A - Active, U - Update, Q - Query, R - Reply,
r - Reply status
P 10.1.1.0/24, 1 successors, FD is 25625600
via Connected, Vlan1
P 10.1.2.0/24, 1 successors, FD is 2169856
via Connected, Serial0/0/0
P 10.1.3.0/24, 1 successors, FD is 2169856
via Connected, Serial0/0/1
P 10.1.4.0/24, 1 successors, FD is 2169856
via Connected, Serial0/1/0
P 10.1.5.0/24, 1 successors, FD is 28160
via Connected, FastEthernet0/0
P 172.16.10.0/24, 1 successors, FD is 28160
via 10.1.5.2 (28160/25600), FastEthernet0/0
P 192.168.10.0/24, 2 successors, FD is 2172416
via 10.1.3.2 (2172416/28160), Serial0/0/1
via 10.1.2.2 (2172416/28160), Serial0/0/0
P 192.168.20.0/24, 2 successors, FD is 2172416
via 10.1.3.2 (2172416/28160), Serial0/0/1
via 10.1.2.2 (2172416/28160), Serial0/0/0
P 192.168.30.0/24, 1 successors, FD is 2172416
via 10.1.4.2 (2172416/28160), Serial0/1/0
P 192.168.40.0/24, 1 successors, FD is 2172416
via 10.1.4.2 (2172416/28160), Serial0/1/0
the "P" preceding each entry is for PASSIVE
these routes are in a passive state, which is good
if they move to an ACTIVE state, it means the have lost their path in the network and looking for a replacement.
Each entry also shows the FEASIBLE DISTANCE, the next hop address, and the local egress interface
Corp# show ip eigrp neighbors
IP-EIGRP neighbors for process 10
H Address Interface Hold Uptime SRTT RTO Q Seq
(sec) (ms) Cnt Num
0 10.1.5.2 Fa0/0 14 02:00:05 40 1000 0 19
1 10.1.3.2 Se0/0/1 13 01:59:59 40 1000 0 14
2 10.1.2.2 Se0/0/0 13 01:59:59 40 1000 0 13
3 10.1.4.2 Se0/1/0 12 01:59:57 40 1000 0 15
fields:
H - the order in which the neighbors were discovered
hold - how long the router will wait for a hello packet
uptime - how long the neigborship has been established
SRTT - smooth round trip timer - the time it takes for a round trip from this router, to neighbor, and back.
SRTT is used to determine how long to wait for a MULTICAST reply.
if a reply isnt received in time, the router switches to UNICASTS
RTO - Retransmission Time Out- is the time EIGRP waits before retransmitting a packet from the retransmission queue
Q - indicates wheter there are oustanding messages in the queue
Seq - indicates the sequence number of the last update from that neighbor. This is used to maintain syncrhonization and avoid duplicate or out-of-sequence processing of messages
Corp# show ip route eigrp
172.16.0.0/24 is subnetted, 1 subnets
D 172.16.10.0 [90/28160] via 10.1.5.2, 02:08:04, FastEthernet0/0
D 192.168.10.0/24 [90/2172416] via 10.1.3.2, 02:07:59, Serial0/0/1
[90/2172416] via 10.1.2.2, 02:07:59, Serial0/0/0
D 192.168.20.0/24 [90/2172416] via 10.1.3.2, 02:07:59, Serial0/0/1
[90/2172416] via 10.1.2.2, 02:07:59, Serial0/0/0
D 192.168.30.0/24 [90/2172416] via 10.1.4.2, 02:07:58, Serial0/1/0
D 192.168.40.0/24 [90/2172416] via 10.1.4.2, 02:07:58, Serial0/1/0
IP-EIGRP interfaces for process 10
Xmit Queue Mean Pacing Time Multicast Pending
Interface Peers Un/Reliable SRTT Un/Reliable Flow Timer Routes
Vlan 0 0/0 1236 0/10 0 0
Fa0/0 1 0/0 1236 0/10 0 0
Se0/1/0 1 0/0 1236 0/10 0 0
Se0/0/1 1 0/0 1236 0/10 0 0
Se0/0/0 1 0/0 1236 0/10 0 0
Corp# show ip protocols
Routing Protocol is "eigrp 10 "
Outgoing update filter list for all interfaces is not set
Incoming update filter list for all interfaces is not set
Default networks flagged in outgoing updates
Default networks accepted from incoming updates
Redistributing: eigrp 10
EIGRP-IPv4 Protocol for AS(10)
Metric weight K1=1, K2=0, K3=1, K4=0, K5=0 using K1 bandwidth and K2 delay by default
NSF-aware route hold timer is 240
Router-ID: 10.1.1.1
Topology : 0 (base)
Active Timer: 3 min
Distance: internal 90 external 170
Maximum path: 4
Maximum hopcount 100
Maximum metric variance 1
Automatic Summarization: disabled
Automatic address summarization:
Maximum path: 4
Routing for Networks:
10.0.0.0
Routing Information Sources:
Gateway Distance Last Update
10.1.5.2 90 0
10.1.3.2 90 8936
10.1.4.2 90 9511
10.1.2.2 90 9597
Distance: internal 90 external 170
Routing Protocol is "rip"
Sending updates every 30 seconds, next due in 13 seconds
Invalid after 180 seconds, hold down 180, flushed after 240
Outgoing update filter list for all interfaces is not set
Incoming update filter list for all interfaces is not set
Redistributing: rip
Default version control: send version 2, receive 2
Interface Send Recv Triggered RIP Key-chain
Vlan1 2 2
FastEthernet0/0 2 2
Serial0/0/1 2 2
Serial0/1/0 2 2
Serial0/0/0 2 2
Automatic network summarization is not in effect
Maximum path: 4
Routing for Networks:
10.0.0.0
Passive Interface(s):
Routing Information Sources:
Gateway Distance Last Update
10.1.5.2 120 00:00:05
10.1.3.2 120 00:00:12
10.1.2.2 120 00:00:12
10.1.4.2 120 00:00:17
Distance: (default is 120)
corp# debug eigrp packet
break into two columns for readability
Observations:
There doesnt appear to be a pattern in the order each router is addressed, except that the TO's and FROM"s are grouped together
The TO messages dont show the destination IP, only the egress local interface
The FROM messages do show the remote IP, as well as the local ingress interface
Corp#
EIGRP: Received HELLO on FastEthernet0/0 nbr 10.1.5.2
AS 10, Flags 0x0, Seq 18/0 idbQ 0/0
hello from R3
Corp#
EIGRP: Received HELLO on Serial0/1/0 nbr 10.1.4.2
AS 10, Flags 0x0, Seq 16/0 idbQ 0/0
hello from R2
Corp#
EIGRP: Received HELLO on Serial0/0/0 nbr 10.1.2.2
AS 10, Flags 0x0, Seq 19/0 idbQ 0/0
hello from R1
------------------------------------------------------------
Corp#
EIGRP: Sending HELLO on Serial0/1/0
AS 10, Flags 0x0, Seq 21/0 idbQ 0/0 iidbQ un/rely 0/0
hello to R2
Corp#
EIGRP: Sending HELLO on FastEthernet0/0
AS 10, Flags 0x0, Seq 21/0 idbQ 0/0 iidbQ un/rely 0/0
hello to R3
Corp#
EIGRP: Sending HELLO on Serial0/0/1
AS 10, Flags 0x0, Seq 21/0 idbQ 0/0 iidbQ un/rely 0/0
hello to R1
Corp#
EIGRP: Sending HELLO on Serial0/0/0
AS 10, Flags 0x0, Seq 21/0 idbQ 0/0 iidbQ un/rely 0/0
hello to R1
Corp#
EIGRP: Sending HELLO on Vlan1
AS 10, Flags 0x0, Seq 21/0 idbQ 0/0 iidbQ un/rely 0/0
hello to switch card (not a router....)
------------------------------------------------------------
Corp#
EIGRP: Received HELLO on Serial0/0/1 nbr 10.1.3.2
AS 10, Flags 0x0, Seq 19/0 idbQ 0/0
hello from R1
Corp#
EIGRP: Received HELLO on FastEthernet0/0 nbr 10.1.5.2
AS 10, Flags 0x0, Seq 18/0 idbQ 0/0
hello from R3
Corp#
EIGRP: Received HELLO on Serial0/0/0 nbr 10.1.2.2
AS 10, Flags 0x0, Seq 19/0 idbQ 0/0
hello from R1
Corp#
EIGRP: Received HELLO on Serial0/1/0 nbr 10.1.4.2
AS 10, Flags 0x0, Seq 16/0 idbQ 0/0
hello from R2
------------------------------------------------------------
Corp#
EIGRP: Sending HELLO on Serial0/1/0
AS 10, Flags 0x0, Seq 21/0 idbQ 0/0 iidbQ un/rely 0/0
hello to R2... no neighbor IP?
Corp#
EIGRP: Sending HELLO on Serial0/0/0
AS 10, Flags 0x0, Seq 21/0 idbQ 0/0 iidbQ un/rely 0/0
hello to R1... no neighbor IP?
Corp#
EIGRP: Sending HELLO on FastEthernet0/0
AS 10, Flags 0x0, Seq 21/0 idbQ 0/0 iidbQ un/rely 0/0
hello to R3... no neighbor IP?
Corp#
EIGRP: Sending HELLO on Serial0/0/1
AS 10, Flags 0x0, Seq 21/0 idbQ 0/0 iidbQ un/rely 0/0
hello to R1
Corp#
EIGRP: Sending HELLO on Vlan1
AS 10, Flags 0x0, Seq 21/0 idbQ 0/0 iidbQ un/rely 0/0
hello to switch card (not a router)
------------------------------------------------------------
OUTPUT CONTINUES IN NEXT COLUMN
Corp#
EIGRP: Received HELLO on Serial0/0/1 nbr 10.1.3.2
AS 10, Flags 0x0, Seq 19/0 idbQ 0/0
hello from R1
Corp#
EIGRP: Received HELLO on FastEthernet0/0 nbr 10.1.5.2
AS 10, Flags 0x0, Seq 18/0 idbQ 0/0
hello from R3
Corp#
EIGRP: Received HELLO on Serial0/0/0 nbr 10.1.2.2
AS 10, Flags 0x0, Seq 19/0 idbQ 0/0
hello from R1
Corp#
EIGRP: Received HELLO on Serial0/1/0 nbr 10.1.4.2
AS 10, Flags 0x0, Seq 16/0 idbQ 0/0
hello from R2
------------------------------------------------------------
Corp#
EIGRP: Sending HELLO on Serial0/1/0
AS 10, Flags 0x0, Seq 21/0 idbQ 0/0 iidbQ un/rely 0/0
hello to R2
Corp#
EIGRP: Sending HELLO on Serial0/0/0
AS 10, Flags 0x0, Seq 21/0 idbQ 0/0 iidbQ un/rely 0/0
hello to R1
Corp#
EIGRP: Sending HELLO on Vlan1
AS 10, Flags 0x0, Seq 21/0 idbQ 0/0 iidbQ un/rely 0/0
hello to Corp switchcard
Corp#
EIGRP: Sending HELLO on Serial0/0/1
AS 10, Flags 0x0, Seq 21/0 idbQ 0/0 iidbQ un/rely 0/0
hello to R1
Corp#
EIGRP: Sending HELLO on FastEthernet0/0
AS 10, Flags 0x0, Seq 21/0 idbQ 0/0 iidbQ un/rely 0/0
hello to R3... no neighbor IP?
------------------------------------------------------------
Corp#
EIGRP: Received HELLO on Serial0/0/1 nbr 10.1.3.2
AS 10, Flags 0x0, Seq 19/0 idbQ 0/0
hello from R1
Corp#
EIGRP: Received HELLO on FastEthernet0/0 nbr 10.1.5.2
AS 10, Flags 0x0, Seq 18/0 idbQ 0/0
hello from R3
Corp#
EIGRP: Received HELLO on Serial0/1/0 nbr 10.1.4.2
AS 10, Flags 0x0, Seq 16/0 idbQ 0/0
hello from R2
Corp#
EIGRP: Received HELLO on Serial0/0/0 nbr 10.1.2.2
AS 10, Flags 0x0, Seq 19/0 idbQ 0/0
hello from R1
------------------------------------------------------------
Corp#
EIGRP: Sending HELLO on Serial0/1/0
AS 10, Flags 0x0, Seq 21/0 idbQ 0/0 iidbQ un/rely 0/0
hello to R2
Corp#
EIGRP: Sending HELLO on Vlan1
AS 10, Flags 0x0, Seq 21/0 idbQ 0/0 iidbQ un/rely 0/0
hello to Corp switchcard
EIGRP: Sending HELLO on Serial0/0/0
AS 10, Flags 0x0, Seq 21/0 idbQ 0/0 iidbQ un/rely 0/0
hello to R1
EIGRP: Sending HELLO on Serial0/0/1
AS 10, Flags 0x0, Seq 21/0 idbQ 0/0 iidbQ un/rely 0/0
hello to R1
Corp#
EIGRP: Sending HELLO on FastEthernet0/0
AS 10, Flags 0x0, Seq 21/0 idbQ 0/0 iidbQ un/rely 0/0
hello to R3
------------------------------------------------------------
Now some videos. To reinforce EIGRP concepts, and lead into OSPF
OSPF - OPEN SHORTEST PATH FIRST
Before enabling OSPF, we'll turn off RIP and EIGRP on all four routers.
Device(config)# no router eigrp 10
Device(config)# no router rip
The OSPF configs for the local egress ip address
Corp(config)# router ospf 132
Corp(config)# network 10.1.0.0 0.0.255.255 area 0
R1(config)# router ospf 1
R1(config)# network 10.1.0.0 0.0.255.255 area 0
R1(config)# network 192.168.0.0 0.0.255.255 area 0
R2(config)# router ospf 45678
R2(config)# network 10.0.0.0 0.0.0.255 area 0
R2(config)# network 192.168.30.1 0.0.0.0 area 0
R2(config)# network 192.168.40.1 0.0.0.0 area 0
all 32 bits of the mask are specified for the 192 entries;
these are not network id's, they are HOST id's of the specific interfaces, which are EGRESS interfaces on the router we are configuring
R3(config)# router ospf 1
R2(config)# network 10.1.5.2 0.0.0.255 area 0
R2(config)# network 172.16.10.0 0.0.0.255 area 0
Wildcard Masks
these notes are not intended to be a precise explanation of wlidcard masking, but rather a look into my thought process as I am learning the concept.
resources:
traceroute blog examples
routerjockey blog examples
subnetonline wildcard calculator
Ch 9 Exam Essentials
1. Know EIGRP features
classless (like RipV2 and OSPF)
distance vector
supports IP, IPX, appleTalk, IPV6
supports summaries and discontiguous networks
uses the Diffusing Update Algorithm (DUAL) to maintain route information
uses RTP to communicate with other EIGRP routers
uses the concept of an autonomous system to describe the set of contiguous routers that run the same routing protocol and share routing information
considered CLASSLESS- includes the subnet mask in its route updates
sends traditional distance-vector updates containing info about networks plus the cost of reaching them from the perspective of the advertising router
but not strictly distance-vector. Has link-state characteristics: synchronizes routing tables between neighbors at startup and then sends specific updates only when topology changes.
max hop count of 255 (default is 100)
but hop count is NOT a metric, like in RIP. Hop count is how many routers an EIGRP route update can traverse before being discarded. This limits the size of the AS.
distance vector
supports IP, IPX, appleTalk, IPV6
supports summaries and discontiguous networks
uses the Diffusing Update Algorithm (DUAL) to maintain route information
uses RTP to communicate with other EIGRP routers
uses the concept of an autonomous system to describe the set of contiguous routers that run the same routing protocol and share routing information
considered CLASSLESS- includes the subnet mask in its route updates
sends traditional distance-vector updates containing info about networks plus the cost of reaching them from the perspective of the advertising router
but not strictly distance-vector. Has link-state characteristics: synchronizes routing tables between neighbors at startup and then sends specific updates only when topology changes.
max hop count of 255 (default is 100)
but hop count is NOT a metric, like in RIP. Hop count is how many routers an EIGRP route update can traverse before being discarded. This limits the size of the AS.
2. Know how to configure EIGRP
the router eigrp [as] command turns EIGRP routing on in the router. Unlike RIPv1, EIGRP uses classless routing. BUT you can still configure as classful.
R1(config)# router eigrp 10
enters router config mode
R1(config-router)# network 10.0.0.0
on this router, interfaces that fall within 10.0.0.0 will advertise EIGRP info
R1(config)# router eigrp 10
enters router config mode
R1(config-router)# network 10.0.0.0
on this router, interfaces that fall within 10.0.0.0 will advertise EIGRP info
3. Know how to verify EIGRP operation
Corp#
show ip
protocols
Corp# show ip route
Corp# show ip route eigrp
Corp# show ip eigrp neighbors
Corp# show ip eigrp topology
Corp# show ip eigrp interfaces
Corp# show ip route
Corp# show ip route eigrp
Corp# show ip eigrp neighbors
Corp# show ip eigrp topology
Corp# show ip eigrp interfaces
Corp#
show ip
protocols
info about all active routing protocols
info about all active routing protocols
Routing Protocol is "eigrp 10 "
Outgoing update filter list for all interfaces is not set
Incoming update filter list for all interfaces is not set
Default networks flagged in outgoing updates
Default networks accepted from incoming updates
Redistributing: eigrp 10
EIGRP-IPv4 Protocol for AS(10)
Metric weight K1=1, K2=0, K3=1, K4=0, K5=0
NSF-aware route hold timer is 240
Router-ID: 10.1.1.1
Topology : 0 (base)
Active Timer: 3 min
Distance: internal 90 external 170
Maximum path: 4
Maximum hopcount 100
Maximum metric variance 1
Automatic Summarization: disabled
Automatic address summarization:
Maximum path: 4
Routing for Networks:
10.0.0.0
Routing Information Sources:
Gateway Distance Last Update
10.1.2.2 90 200105
10.1.3.2 90 200113
10.1.4.2 90 254351
10.1.5.2 90 303742
Distance: internal 90 external 170
Corp#
show ip
protocols
(continued)
Routing Protocol is "rip"
Sending updates every 30 seconds, next due in 6 seconds
Invalid after 180 seconds, hold down 180, flushed after 240
Outgoing update filter list for all interfaces is not set
Incoming update filter list for all interfaces is not set
Redistributing: rip
Default version control: send version 2, receive 2
Interface Send Recv Triggered RIP Key-chain
Vlan1 2 2
FastEthernet0/0 2 2
Serial0/1/0 2 2
Serial0/0/1 2 2
Serial0/0/0 2 2
Automatic network summarization is not in effect
Maximum path: 4
Routing for Networks:
10.0.0.0
Passive Interface(s):
Routing Information Sources:
Gateway Distance Last Update
10.1.5.2 120 00:00:15
10.1.3.2 120 00:00:01
10.1.2.2 120 00:00:01
10.1.4.2 120 00:00:17
Distance: (default is 120)
Corp#
show ip
route
entire routing table
entire routing table
Codes: L - local, C - connected, S - static, R - RIP, M - mobile, B - BGP
D - EIGRP, EX - EIGRP external, O - OSPF, IA - OSPF inter area
N1 - OSPF NSSA external type 1, N2 - OSPF NSSA external type 2
E1 - OSPF external type 1, E2 - OSPF external type 2, E - EGP
i - IS-IS, L1 - IS-IS level-1, L2 - IS-IS level-2, ia - IS-IS inter area
* - candidate default, U - per-user static route, o - ODR
P - periodic downloaded static route
Gateway of last resort is not set
10.0.0.0/8 is variably subnetted, 10 subnets, 2 masks
C 10.1.1.0/24 is directly connected, Vlan1
L 10.1.1.1/32 is directly connected, Vlan1
C 10.1.2.0/24 is directly connected, Serial0/0/0
L 10.1.2.1/32 is directly connected, Serial0/0/0
C 10.1.3.0/24 is directly connected, Serial0/0/1
L 10.1.3.1/32 is directly connected, Serial0/0/1
C 10.1.4.0/24 is directly connected, Serial0/1/0
L 10.1.4.1/32 is directly connected, Serial0/1/0
C 10.1.5.0/24 is directly connected, FastEthernet0/0
L 10.1.5.1/32 is directly connected, FastEthernet0/0
172.16.0.0/16 is variably subnetted, 2 subnets, 2 masks
R 172.16.0.0/16 [120/1] via 10.1.5.2, 00:00:14, FastEthernet0/0
D 172.16.10.0/24 [90/28160] via 10.1.5.2, 00:07:23, FastEthernet0/0
D 192.168.10.0/24 [90/2172416] via 10.1.3.2, 00:09:13, Serial0/0/1
[90/2172416] via 10.1.2.2, 00:09:13, Serial0/0/0
D 192.168.20.0/24 [90/2172416] via 10.1.3.2, 00:09:13, Serial0/0/1
[90/2172416] via 10.1.2.2, 00:09:13, Serial0/0/0
D 192.168.30.0/24 [90/2172416] via 10.1.4.2, 00:08:59, Serial0/1/0
D 192.168.40.0/24 [90/2172416] via 10.1.4.2, 00:08:59, Serial0/1/0
Shows the entire routing table
Corp#
show ip
eigrp toplogy
all nets the Corp router can see, including on the other side of other routers
all nets the Corp router can see, including on the other side of other routers
IP-EIGRP Topology Table for AS 10/ID(10.1.5.1)
Codes: P - Passive, A - Active, U - Update, Q - Query, R - Reply,
r - Reply status
directly connected via local egress interface
P 10.1.1.0/24, 1 successors, FD is 25625600
via Connected, Vlan1
P 10.1.2.0/24, 1 successors, FD is 2169856
via Connected, Serial0/0/0
P 10.1.3.0/24, 1 successors, FD is 2169856
via Connected, Serial0/0/1
P 10.1.4.0/24, 1 successors, FD is 2169856
via Connected, Serial0/1/0
P 10.1.5.0/24, 1 successors, FD is 28160
via Connected, FastEthernet0/0
remotely connected via remote ingress ip address
P 172.16.10.0/24, 1 successors, FD is 28160
via 10.1.5.2 (28160/25600), FastEthernet0/0
P 192.168.10.0/24, 2 successors, FD is 2172416
via 10.1.3.2 (2172416/28160), Serial0/0/1
via 10.1.2.2 (2172416/28160), Serial0/0/0
P 192.168.20.0/24, 2 successors, FD is 2172416
via 10.1.3.2 (2172416/28160), Serial0/0/1
via 10.1.2.2 (2172416/28160), Serial0/0/0
P 192.168.30.0/24, 1 successors, FD is 2172416
via 10.1.4.2 (2172416/28160), Serial0/1/0
P 192.168.40.0/24, 1 successors, FD is 2172416
via 10.1.4.2 (2172416/28160), Serial0/1/0
Corp#
show ip
eigrp interfaces
local interfaces on Corp, with peer data, 5 total, including VLAN1 (0 peers, no router on this network)
local interfaces on Corp, with peer data, 5 total, including VLAN1 (0 peers, no router on this network)
IP-EIGRP interfaces for process 10
Xmit Queue Mean Pacing Time Multicast Pending
Interface Peers Un/Reliable SRTT Un/Reliable Flow Timer Routes
Vlan 0 0/0 1236 0/10 0 0
Fa0/0 1 0/0 1236 0/10 0 0
Se0/0/1 1 0/0 1236 0/10 0 0
Se0/1/0 1 0/0 1236 0/10 0 0
Se0/0/0 1 0/0 1236 0/10 0 0
Corp#
show ip
eigrp neighbors
remote interfaces on the 4 neighboring routers
remote interfaces on the 4 neighboring routers
IP-EIGRP neighbors for process 10
H Address Interface Hold Uptime SRTT RTO Q Seq
(sec) (ms) Cnt Num
0 10.1.2.2 Se0/0/0 14 00:54:33 40 1000 0 58
1 10.1.3.2 Se0/0/1 10 00:54:33 40 1000 0 57
2 10.1.4.2 Se0/1/0 14 00:53:38 40 1000 0 51
3 10.1.5.2 Fa0/0 11 00:52:49 40 1000 0 33
4. Compare OSPF and RIPv1
RIPv1 is distance-vector and supports only classful routing. No VLSM
OSPF is link-state and supports VLSM and classless routing
OSPF is link-state and supports VLSM and classless routing
5. Know how OSPF routers become neighboars and/or adjacent
they become neighbors when they see eachother's hello packets.
area id must match, links must be on the same subnet, hello/dead timers must be the same.
OSPF only shares routes with neigbors who have also established adjacencies. NOT ALL NEIGHBORS become adjacent.
When an OSPF router first receives a hello packet, it verifies that the data in some fields matches its own locally configured information. Should any of the checked data be different, the hello packet is discarded and not processed. The data fields verified are the Area ID, Authentication, Network Mask (on broadcast networks), Hello Interval, Router Dead Interval, and Options fields. If this information doesn’t match, then neighborship is stuck in the down stage. packetpushers.net
area id must match, links must be on the same subnet, hello/dead timers must be the same.
OSPF only shares routes with neigbors who have also established adjacencies. NOT ALL NEIGHBORS become adjacent.
When an OSPF router first receives a hello packet, it verifies that the data in some fields matches its own locally configured information. Should any of the checked data be different, the hello packet is discarded and not processed. The data fields verified are the Area ID, Authentication, Network Mask (on broadcast networks), Hello Interval, Router Dead Interval, and Options fields. If this information doesn’t match, then neighborship is stuck in the down stage. packetpushers.net
6. Be able to configure single-area OSPF
two commands:
router ospf [process id]
network x.x.x.x y.y.y.y area z
router ospf [process id]
network x.x.x.x y.y.y.y area z
7. Be able to verify the operation of OSPF
Corp#
show ip
protocols
Corp# show ip route
Corp# show ip ospf
Corp# show ip ospf database
Corp# show ip ospf interface
Corp# show ip ospf neighbor
Flashcards
Corp# show ip route
Corp# show ip ospf
Corp# show ip ospf database
Corp# show ip ospf interface
Corp# show ip ospf neighbor
IOS 15.1
Corp# show ip protocols
Corp# show ip protocols
Routing Protocol is "ospf 132"
Outgoing update filter list for all interfaces is not set
Incoming update filter list for all interfaces is not set
Router ID 10.1.5.1
Number of areas in this router is 1. 1 normal 0 stub 0 nssa
Maximum path: 4
Routing for Networks:
10.1.0.0 0.0.255.255 area 0
Routing Information Sources:
Gateway Distance Last Update
10.1.5.1 110 00:08:51
172.16.10.1 110 00:08:51
192.168.20.1 110 00:12:53
192.168.40.1 110 00:09:35
Distance: (default is 110)
IOS 15.1
Corp# show ip route
Corp# show ip route
10.0.0.0/8 is variably subnetted, 10 subnets, 2 masks
C 10.1.1.0/24 is directly connected, Vlan1
L 10.1.1.1/32 is directly connected, Vlan1
C 10.1.2.0/24 is directly connected, Serial0/0/0
L 10.1.2.1/32 is directly connected, Serial0/0/0
C 10.1.3.0/24 is directly connected, Serial0/0/1
L 10.1.3.1/32 is directly connected, Serial0/0/1
C 10.1.4.0/24 is directly connected, Serial0/1/0
L 10.1.4.1/32 is directly connected, Serial0/1/0
C 10.1.5.0/24 is directly connected, FastEthernet0/0
L 10.1.5.1/32 is directly connected, FastEthernet0/0
172.16.0.0/24 is subnetted, 1 subnets
O 172.16.10.0/24 [110/10] via 10.1.5.2, 00:09:09, FastEthernet0/0
O 192.168.10.0/24 [110/65] via 10.1.2.2, 00:13:11, Serial0/0/0
O 192.168.20.0/24 [110/65] via 10.1.2.2, 00:13:01, Serial0/0/0
O 192.168.30.0/24 [110/65] via 10.1.4.2, 00:09:54, Serial0/1/0
O 192.168.40.0/24 [110/65] via 10.1.4.2, 00:09:54, Serial0/1/0
IOS 15.1
Corp# show ip ospf
Corp# show ip ospf
Routing Process "ospf 132" with ID 10.1.5.1
Supports only single TOS(TOS0) routes
Supports opaque LSA
SPF schedule delay 5 secs, Hold time between two SPFs 10 secs
Minimum LSA interval 5 secs. Minimum LSA arrival 1 secs
Number of external LSA 0. Checksum Sum 0x000000
Number of opaque AS LSA 0. Checksum Sum 0x000000
Number of DCbitless external and opaque AS LSA 0
Number of DoNotAge external and opaque AS LSA 0
Number of areas in this router is 1. 1 normal 0 stub 0 nssa
External flood list length 0
Area BACKBONE(0)
Number of interfaces in this area is 5
Area has no authentication
SPF algorithm executed 7 times
Area ranges are
Number of LSA 5. Checksum Sum 0x034486
Number of opaque link LSA 0. Checksum Sum 0x000000
Number of DCbitless LSA 0
Number of indication LSA 0
Number of DoNotAge LSA 0
Flood list length 0
IOS 15.1
Corp# show ip ospf database
we are seeing three connected routers + our own router (Corp at 10.1.5.1)
Corp# show ip ospf database
OSPF Router with ID (10.1.5.1) (Process ID 132)
Router Link States (Area 0)
Link ID ADV Router Age Seq# Checksum Link count
192.168.20.1 192.168.20.1 854 0x80000006 0x00ae08 6
192.168.40.1 192.168.40.1 656 0x80000004 0x006bc6 4
10.1.5.1 10.1.5.1 612 0x8000000f 0x00ab77 8
172.16.10.1 172.16.10.1 612 0x80000003 0x00b30d 2
Net Link States (Area 0)
Link ID ADV Router Age Seq# Checksum
10.1.5.1 10.1.5.1 612 0x80000001 0x00cc34
ADV Router aka RID/Router ID, the highest IP address on the router
we are seeing three connected routers + our own router (Corp at 10.1.5.1)
IOS 15.1
Corp# show ip ospf interface
Corp# show ip ospf interface
Vlan1 is up, line protocol is up
Internet address is 10.1.1.1/24, Area 0
Process ID 132, Router ID 10.1.5.1, Network Type BROADCAST, Cost: 1
Transmit Delay is 1 sec, State DR, Priority 1
Designated Router (ID) 10.1.5.1, Interface address 10.1.1.1
No backup designated router on this network
Timer intervals configured, Hello 10, Dead 40, Wait 40, Retransmit 5
Hello due in 00:00:08
Index 1/1, flood queue length 0
Next 0x0(0)/0x0(0)
Last flood scan length is 1, maximum is 1
Last flood scan time is 0 msec, maximum is 0 msec
Neighbor Count is 0, Adjacent neighbor count is 0
Suppress hello for 0 neighbor(s)
FastEthernet0/0 is up, line protocol is up
Internet address is 10.1.5.1/24, Area 0
Process ID 132, Router ID 10.1.5.1, Network Type BROADCAST, Cost: 1
Transmit Delay is 1 sec, State DR, Priority 1
Designated Router (ID) 10.1.5.1, Interface address 10.1.5.1
Backup Designated Router (ID) 172.16.10.1, Interface address 10.1.5.2
Timer intervals configured, Hello 10, Dead 40, Wait 40, Retransmit 5
Hello due in 00:00:07
Index 2/2, flood queue length 0
Next 0x0(0)/0x0(0)
Last flood scan length is 1, maximum is 1
Last flood scan time is 0 msec, maximum is 0 msec
Neighbor Count is 1, Adjacent neighbor count is 1
Adjacent with neighbor 172.16.10.1 (Backup Designated Router)
Suppress hello for 0 neighbor(s)
Serial0/0/1 is up, line protocol is up
Internet address is 10.1.3.1/24, Area 0
Process ID 132, Router ID 10.1.5.1, Network Type POINT-TO-POINT, Cost: 64
Transmit Delay is 1 sec, State POINT-TO-POINT,
Timer intervals configured, Hello 10, Dead 40, Wait 40, Retransmit 5
Hello due in 00:00:07
Index 3/3, flood queue length 0
Next 0x0(0)/0x0(0)
Last flood scan length is 1, maximum is 1
Last flood scan time is 0 msec, maximum is 0 msec
Neighbor Count is 1 , Adjacent neighbor count is 1
Adjacent with neighbor 192.168.20.1
Suppress hello for 0 neighbor(s)
Serial0/1/0 is up, line protocol is up
Internet address is 10.1.4.1/24, Area 0
Process ID 132, Router ID 10.1.5.1, Network Type POINT-TO-POINT, Cost: 64
Transmit Delay is 1 sec, State POINT-TO-POINT,
Timer intervals configured, Hello 10, Dead 40, Wait 40, Retransmit 5
Hello due in 00:00:07
Index 4/4, flood queue length 0
Next 0x0(0)/0x0(0)
Last flood scan length is 1, maximum is 1
Last flood scan time is 0 msec, maximum is 0 msec
Neighbor Count is 1 , Adjacent neighbor count is 1
Adjacent with neighbor 192.168.40.1
Suppress hello for 0 neighbor(s)
Serial0/0/0 is up, line protocol is up
Internet address is 10.1.2.1/24, Area 0
Process ID 132, Router ID 10.1.5.1, Network Type POINT-TO-POINT, Cost: 64
Transmit Delay is 1 sec, State POINT-TO-POINT,
Timer intervals configured, Hello 10, Dead 40, Wait 40, Retransmit 5
Hello due in 00:00:07
Index 5/5, flood queue length 0
Next 0x0(0)/0x0(0)
Last flood scan length is 1, maximum is 1
Last flood scan time is 0 msec, maximum is 0 msec
Neighbor Count is 1 , Adjacent neighbor count is 1
Adjacent with neighbor 192.168.20.1
Suppress hello for 0 neighbor(s)
IOS 15.1
Corp# show ip ospf neighbor
Corp# show ip ospf neighbor
Neighbor ID Pri State Dead Time Address Interface
192.168.20.1 0 FULL/ - 00:00:31 10.1.3.2 Serial0/0/1
192.168.40.1 0 FULL/ - 00:00:33 10.1.4.2 Serial0/1/0
192.168.20.1 0 FULL/ - 00:00:31 10.1.2.2 Serial0/0/0
172.16.10.1 1 FULL/BDR 00:00:32 10.1.5.2 FastEthernet0/0
Flashcards
Chapter 9 Written Lab 9.0
1. What four routed protocols are supported by EIGRP?
IPX, IPv4, IPv6, AppleTalk
2. When is redistribution required for EIGRP?
when there are multiple autonomous systems
redistribution is required when more than one EIGRP session or process is running and they are identified with different ASNs.
redistribution shares toplogy information between EIGRP sessions
redistribution is required when more than one EIGRP session or process is running and they are identified with different ASNs.
redistribution shares toplogy information between EIGRP sessions
3. What command would be used to enable EIGRP with an autonmous system number of 300?
router eigrp 300
4. What command will tell EIGRP that it is connected to network 172.10.0.0?
network 172.10.0.0
5. What type of EIGRP interface will neither send nor receive Hello packets?
passive-interface s0/0
6. Write the command that will enable OSPF process 101 on a router
router ospf 101
7. Write the command that will display details of all OSFP routing processes enabled on a router
show ip ospf
8. Write the command that will display interface-specific OSPF information
show ip ospf interface
9. Write the command that will display all OSPF neighbors
show ip ospf neighbor
10. Write the command that will display all different OSPF route types that are currently known by the router
show ip route ospf
Chapter 9 Hands-On Labs
Build the network and configure interfaces
LabA(config)# int f0/0
LabA(config-if)# ip addr 172.16.10.1 255.255.255.0
LabA(config-if)# no shut
LabB(config)# int f0/0
LabB(config-if)# ip addr 172.16.10.2 255.255.255.0
LabB(config-if)# no shut
LabB(config-if)# int s0/0/0
LabB(config-if)# ip addr 172.16.20.1 255.255.255.0
LabB(config-if)# no shut
LabC(config)# int f0/0
LabC(config-if)# ip addr 172.16.30.1 255.255.255.0
LabC(config-if)# no shut
LabC(config-if)# int s0/0/0
LabC(config-if)# ip addr 172.16.20.2 255.255.255.0
LabC(config-if)# no shut
LabC(config-if)# int s0/0/1
LabC(config-if)# ip addr 172.16.40.1 255.255.255.0
LabC(config-if)# no shut
LabD(config)# int s0/0/0
LabD(config-if)# ip addr 172.16.40.2 255.255.255.0
LabD(config-if)# no shut
LabD(config-if)# int f0/0
LabD(config-if)# ip addr 172.16.50.1 255.255.255.0
LabD(config-if)# no shut
9.1 - Configure and Verfiy EIGRP
configure EIGRP on all 4 routers and observe results
LabA
LabA(config)# router eigrp 100
LabA(config-router)# net 172.16.0.0
[no output]
LabA# show ip eigrp neighbors
IP-EIGRP neighbors for process 100
LabA# show ip eigrp topology
IP-EIGRP Topology Table for AS 100/ID(172.16.10.1)
Codes: P - Passive, A - Active, U - Update, Q - Query, R - Reply,
r - Reply status
P 172.16.10.0/24, 1 successors, FD is 28160
via Connected, FastEthernet0/0
LabA# show ip eigrp interfaces
IP-EIGRP interfaces for process 100
Xmit Queue Mean Pacing Time Multicast Pending
Interface Peers Un/Reliable SRTT Un/Reliable Flow Timer Routes
Fa0/0 0 0/0 1236 0/10 0 0
no neighbors at this point since EIGRP is only active on this router. One successor AKA route, which is the connection out of this router.
But note that we have no information about what's on the other side of that link
LabB
LabB(config)# router eigrp 100
LabB(config-router)# net 172.16.0.0
%DUAL-5-NBRCHANGE: IP-EIGRP 100:
Neighbor 172.16.10.1 (FastEthernet0/0) is up: new adjacency
LabB# show ip eigrp neighbors
IP-EIGRP neighbors for process 100
H Address Interface Hold Uptime SRTT RTO Q Seq
(sec) (ms) Cnt Num
0 172.16.10.1 Fa0/0 12 00:00:14 40 1000 0 1
LabB# show ip eigrp topology
IP-EIGRP Topology Table for AS 100/ID(172.16.20.1)
Codes: P - Passive, A - Active, U - Update, Q - Query, R - Reply,
r - Reply status
P 172.16.10.0/24, 1 successors, FD is 28160
via Connected, FastEthernet0/0
P 172.16.20.0/24, 1 successors, FD is 2169856
via Connected, Serial0/0/0
LabB# show ip eigrp interfaces
IP-EIGRP interfaces for process 100
Xmit Queue Mean Pacing Time Multicast Pending
Interface Peers Un/Reliable SRTT Un/Reliable Flow Timer Routes
Fa0/0 1 0/0 1236 0/10 0 0
Se0/0/0 0 0/0 1236 0/10 0 0
We can see a neighbor at .1
We now have two paths out of this router. Left to neighbor. Exit at right is available as successor(route), but again we have no info about what is on the other side, since that router has no EIGRP yet (s0/0/0 has no peers, but is an EIGRP interface)
LabC
LabC(config)# router eigrp 100
LabC(config-router)# net 172.16.0.0
%DUAL-5-NBRCHANGE: IP-EIGRP 100:
Neighbor 172.16.20.1 (Serial0/0/0) is up: new adjacency
LabC# show ip eigrp neighbors
IP-EIGRP neighbors for process 100
H Address Interface Hold Uptime SRTT RTO Q Seq
(sec) (ms) Cnt Num
0 172.16.20.1 Se0/0/0 12 00:00:25 40 1000 0 8
LabC# show ip eigrp toplogy
IP-EIGRP Topology Table for AS 100/ID(172.16.40.1)
Codes: P - Passive, A - Active, U - Update, Q - Query, R - Reply,
r - Reply status
P 172.16.10.0/24, 1 successors, FD is 2172416
via 172.16.20.1 (2172416/28160), Serial0/0/0
P 172.16.20.0/24, 1 successors, FD is 2169856
via Connected, Serial0/0/0
P 172.16.30.0/24, 1 successors, FD is 28160
via Connected, FastEthernet0/0
P 172.16.40.0/24, 1 successors, FD is 2169856
via Connected, Serial0/0/1
LabC# show ip eigrp interfaces
IP-EIGRP interfaces for process 100
Xmit Queue Mean Pacing Time Multicast Pending
Interface Peers Un/Reliable SRTT Un/Reliable Flow Timer Routes
Fa0/0 0 0/0 1236 0/10 0 0
Se0/0/0 1 0/0 1236 0/10 0 0
Se0/0/1 0 0/0 1236 0/10 0 0
.1 router B interface is now a neighbor.
LabC topology shows the 3 direct connected networks AND the network on the other side of LabB since LabB is our EIGRP neighbor
3 eigrp interfaces:
Fa0/0 is ours at LabC- no peers bc there is no eigrp router on the other end
s0/0/0 is our interface out left to LabB which is an EIGRP peer
s0/0/1 is our interface out right which does not see an EIGRP peer but does put that net 172.16.40.0 in our topology
LabD
LabD(config)# router eigrp 100
LabD(config-router)# net 172.16.0.0
%DUAL-5-NBRCHANGE: IP-EIGRP 100:
Neighbor 172.16.40.1 (Serial0/0/0) is up: new adjacency
LabD# show ip eigrp neighbors
IP-EIGRP neighbors for process 100
H Address Interface Hold Uptime SRTT RTO Q Seq
(sec) (ms) Cnt Num
0 172.16.40.1 Se0/0/0 11 00:00:14 40 1000 0 6
LabD# show ip eigrp topology
IP-EIGRP Topology Table for AS 100/ID(172.16.50.1)
Codes: P - Passive, A - Active, U - Update, Q - Query, R - Reply,
r - Reply status
P 172.16.10.0/24, 1 successors, FD is 2684416
via 172.16.40.1 (2684416/2172416), Serial0/0/0
P 172.16.20.0/24, 1 successors, FD is 2681856
via 172.16.40.1 (2681856/2169856), Serial0/0/0
P 172.16.30.0/24, 1 successors, FD is 2172416
via 172.16.40.1 (2172416/28160), Serial0/0/0
P 172.16.40.0/24, 1 successors, FD is 2169856
via Connected, Serial0/0/0
P 172.16.50.0/24, 1 successors, FD is 28160
via Connected, FastEthernet0/0
LabD# show ip eigrp interfaces
IP-EIGRP interfaces for process 100
Xmit Queue Mean Pacing Time Multicast Pending
Interface Peers Un/Reliable SRTT Un/Reliable Flow Timer Routes
Fa0/0 0 0/0 1236 0/10 0 0
Se0/0/0 1 0/0 1236 0/10 0 0
LabC to our left is now a neighbor at 172.16.40.1
toplogy shows a route out to the right (no router on that end)
a route to the left to LabC .40.0
the .10.0, .20.0, and .30.0 networks via info from LabC
2 eigrp interfaces-
fa0/0 out to the right
s0/0/0 out left to LabC
Time to remove EIGRP from all four routers to prepare for the OSPF lab next,
since EIGRP has a lower AD than OSPF
LabA(config)# no router eigrp 100
LabB(config)# no router eigrp 100
LabC(config)# no router eigrp 100
LabD(config)# no router eigrp 100
9.2 - Enabling the OSPF Process
9.3 - Configuring OSPF Interfaces
9.4 - Verifying OSPF Operation
LabA
LabA(config)# router ospf 100
LabA(config-router)# net 172.16.10.1 0.0.0.0 area 0
[no output]
LabA# show ip ospf neighbor
[no output]
LabA# show ip ospf database
OSPF Router with ID (172.16.10.1) (Process ID 100)
Router Link States (Area 0)
Link ID ADV Router Age Seq# Checksum Link count
172.16.10.1 172.16.10.1 44 0x80000001 0x00b24b 1
LabA# show ip ospf interface
FastEthernet0/0 is up, line protocol is up
Internet address is 172.16.10.1/24, Area 0
Process ID 100, Router ID 172.16.10.1, Network Type BROADCAST, Cost: 1
Transmit Delay is 1 sec, State DR, Priority 1
Designated Router (ID) 172.16.10.1, Interface address 172.16.10.1
No backup designated router on this network
Timer intervals configured, Hello 10, Dead 40, Wait 40, Retransmit 5
Hello due in 00:00:08
Index 1/1, flood queue length 0
Next 0x0(0)/0x0(0)
Last flood scan length is 1, maximum is 1
Last flood scan time is 0 msec, maximum is 0 msec
Neighbor Count is 0, Adjacent neighbor count is 0
Suppress hello for 0 neighbor(s)
we're including this router's interface 172.16.10.1 in our ospf area 0
fa0/0 now registers as an ospf interface
the ospf database includes data about this link only.... LabA is counting itself(10.1) as ADVERTISTING router?
the designated router is .1 LabA
LabB
LabB(config)# router ospf 101
LabB(config-router)# net 172.16.10.2 0.0.0.0 area 0
LabB(config-router)# net 172.16.20.1 0.0.0.0 area 0
01:26:36: %OSPF-5-ADJCHG: Process 101, Nbr 172.16.10.1
on FastEthernet0/0 from LOADING to FULL, Loading Done
LabB# show ip ospf neighbor
Neighbor ID Pri State Dead Time Address Interface
172.16.10.1 1 FULL/DR 00:00:33 172.16.10.1
LabB# show ip ospf database
OSPF Router with ID (172.16.20.1) (Process ID 101)
Router Link States (Area 0)
Link ID ADV Router Age Seq# Checksum Link count
172.16.10.1 172.16.10.1 145 0x80000002 0x0067cd 1
172.16.20.1 172.16.20.1 32 0x80000003 0x006e8f 2
Net Link States (Area 0)
Link ID ADV Router Age Seq# Checksum
172.16.10.1 172.16.10.1 145 0x80000001 0x00953d
LabB# show ip ospf interface
FastEthernet0/0 is up, line protocol is up
Internet address is 172.16.10.2/24, Area 0
Process ID 101, Router ID 172.16.20.1, Network Type BROADCAST, Cost: 1
Transmit Delay is 1 sec, State BDR, Priority 1
Designated Router (ID) 172.16.10.1, Interface address 172.16.10.1
Backup Designated Router (ID) 172.16.20.1, Interface address 172.16.10.2
Timer intervals configured, Hello 10, Dead 40, Wait 40, Retransmit 5
Hello due in 00:00:03
Index 1/1, flood queue length 0
Next 0x0(0)/0x0(0)
Last flood scan length is 1, maximum is 1
Last flood scan time is 0 msec, maximum is 0 msec
Neighbor Count is 1, Adjacent neighbor count is 1
Adjacent with neighbor 172.16.10.1 (Designated Router)
Suppress hello for 0 neighbor(s)
Serial0/0/0 is up, line protocol is up
Internet address is 172.16.20.1/24, Area 0
Process ID 101, Router ID 172.16.20.1, Network Type POINT-TO-POINT, Cost: 64
Transmit Delay is 1 sec, State POINT-TO-POINT,
Timer intervals configured, Hello 10, Dead 40, Wait 40, Retransmit 5
Hello due in 00:00:04
Index 2/2, flood queue length 0
Next 0x0(0)/0x0(0)
Last flood scan length is 1, maximum is 1
Last flood scan time is 0 msec, maximum is 0 msec
Suppress hello for 0 neighbor(s)
We've include the two interfaces on this router in the OSPF area
and can now see Router A's interface 10.1 to the left as a neighbor in the area
the "OSPF Database" now shows two links 20.1(local) and 10.1(neighbor) as 'router link states'.
"ADV Router" means advertising router for the two links. The link address is used as the advertising router.
database shows "Net Link States" category with one entry- 172.16.10.1 which is the address of neighbor router to our left
we have two local OSPF interfaces- f0/0 and s0/0/0
LabC
LabC(config)# router ospf 102
LabC(config-router)# net 172.16.20.2 0.0.0.0 area 0
LabC(config-router)# net 172.16.30.1 0.0.0.0 area 0
LabC(config-router)# net 172.16.40.1 0.0.0.0 area 0
01:33:54: %OSPF-5-ADJCHG: Process 102, Nbr 172.16.20.1
on Serial0/0/0 from LOADING to FULL, Loading Done
LabC# show ip ospf neighbor
Neighbor ID Pri State Dead Time Address Interface
172.16.20.1 0 FULL/ - 00:00:30 172.16.20.1 Serial0/0/0
LabC# show ip ospf database
OSPF Router with ID (172.16.40.1) (Process ID 102)
Router Link States (Area 0)
Link ID ADV Router Age Seq# Checksum Link count
172.16.10.1 172.16.10.1 542 0x80000002 0x0067cd 1
172.16.20.1 172.16.20.1 90 0x80000004 0x00a551 3
172.16.40.1 172.16.40.1 37 0x80000004 0x00e47c 4
Net Link States (Area 0)
Link ID ADV Router Age Seq# Checksum
172.16.10.1 172.16.10.1 542 0x80000001 0x00953d
LabC# show ip ospf interface
Serial0/0/0 is up, line protocol is up
Internet address is 172.16.20.2/24, Area 0
Process ID 102, Router ID 172.16.40.1, Network Type POINT-TO-POINT, Cost: 64
Transmit Delay is 1 sec, State POINT-TO-POINT,
Timer intervals configured, Hello 10, Dead 40, Wait 40, Retransmit 5
Hello due in 00:00:01
Index 1/1, flood queue length 0
Next 0x0(0)/0x0(0)
Last flood scan length is 1, maximum is 1
Last flood scan time is 0 msec, maximum is 0 msec
Neighbor Count is 1 , Adjacent neighbor count is 1
Adjacent with neighbor 172.16.20.1
Suppress hello for 0 neighbor(s)
FastEthernet0/0 is up, line protocol is up
Internet address is 172.16.30.1/24, Area 0
Process ID 102, Router ID 172.16.40.1, Network Type BROADCAST, Cost: 1
Transmit Delay is 1 sec, State DR, Priority 1
Designated Router (ID) 172.16.40.1, Interface address 172.16.30.1
No backup designated router on this network
Timer intervals configured, Hello 10, Dead 40, Wait 40, Retransmit 5
Hello due in 00:00:02
Index 2/2, flood queue length 0
Next 0x0(0)/0x0(0)
Last flood scan length is 1, maximum is 1
Last flood scan time is 0 msec, maximum is 0 msec
Neighbor Count is 0, Adjacent neighbor count is 0
Suppress hello for 0 neighbor(s)
Serial0/0/1 is up, line protocol is up
Internet address is 172.16.40.1/24, Area 0
Process ID 102, Router ID 172.16.40.1, Network Type POINT-TO-POINT, Cost: 64
Transmit Delay is 1 sec, State POINT-TO-POINT,
Timer intervals configured, Hello 10, Dead 40, Wait 40, Retransmit 5
Hello due in 00:00:08
Index 3/3, flood queue length 0
Next 0x0(0)/0x0(0)
Last flood scan length is 1, maximum is 1
Last flood scan time is 0 msec, maximum is 0 msec
Suppress hello for 0 neighbor(s)
we include the three nets conneted to labC in the area.. 20.0, 30.0, and 40.0
link to our left, 20.1 is visible as "Neighbor"
OSPF Database-
Router Link States are
10.1(Router A)
20.1(Router B)
40.1(Router C)(This router)
Net Link States
10.1(Router A)... why does only Router A show here?
Reference- router link state vs net link state
Router Link States are type 1 LSAs. It lists all the routers in the area and the number of interfaces. 40.1 has 4 interfaces
Net Link States are the multi-access networks (Type 2 LSAs). The ADV (advertising router) is the DR.
LabD
LabD(config)# router ospf 103
LabD(config-router)# net 172.16.40.2 0.0.0.0 area 0
LabD(config-router)# net 172.16.50.1 0.0.0.0 area 0
01:37:11: %OSPF-5-ADJCHG: Process 103, Nbr 172.16.40.1
on Serial0/0/0 from LOADING to FULL, Loading Done
LabD# show ip ospf neighbor
Neighbor ID Pri State Dead Time Address Interface
172.16.40.1 0 FULL/ - 00:00:32 172.16.40.1 Serial0/0/0
LabD# show ip ospf database
OSPF Router with ID (172.16.50.1) (Process ID 103)
Router Link States (Area 0)
Link ID ADV Router Age Seq# Checksum Link count
172.16.10.1 172.16.10.1 785 0x80000002 0x0067cd 1
172.16.20.1 172.16.20.1 333 0x80000004 0x00a551 3
172.16.40.1 172.16.40.1 111 0x80000005 0x00013b 5
172.16.50.1 172.16.50.1 53 0x80000003 0x001023 3
Net Link States (Area 0)
Link ID ADV Router Age Seq# Checksum
172.16.10.1 172.16.10.1 785 0x80000001 0x00953d
LabD# show ip ospf interface
Serial0/0/0 is up, line protocol is up
Internet address is 172.16.40.2/24, Area 0
Process ID 103, Router ID 172.16.50.1, Network Type POINT-TO-POINT, Cost: 64
Transmit Delay is 1 sec, State POINT-TO-POINT,
Timer intervals configured, Hello 10, Dead 40, Wait 40, Retransmit 5
Hello due in 00:00:01
Index 1/1, flood queue length 0
Next 0x0(0)/0x0(0)
Last flood scan length is 1, maximum is 1
Last flood scan time is 0 msec, maximum is 0 msec
Neighbor Count is 1 , Adjacent neighbor count is 1
Adjacent with neighbor 172.16.40.1
Suppress hello for 0 neighbor(s)
FastEthernet0/0 is up, line protocol is up
Internet address is 172.16.50.1/24, Area 0
Process ID 103, Router ID 172.16.50.1, Network Type BROADCAST, Cost: 1
Transmit Delay is 1 sec, State WAITING, Priority 1
No designated router on this network
No backup designated router on this network
Timer intervals configured, Hello 10, Dead 40, Wait 40, Retransmit 5
Hello due in 00:00:04
Index 2/2, flood queue length 0
Next 0x0(0)/0x0(0)
Last flood scan length is 1, maximum is 1
Last flood scan time is 0 msec, maximum is 0 msec
Neighbor Count is 0, Adjacent neighbor count is 0
Suppress hello for 0 neighbor(s)
observations
the OSPF databases now match across all 4 routers.
NOTE that this is a database of routers, identified by router ID. It is not a topology that lists routers AND routes, like in the "equivalent" eigrp command.show eigrp topology
----------------------------------------------------------------------------------
PAUSE- a tale of a misconfigured network
After a 9 month hiatus, I am reviewing this book and have made it back to Chapter 9. I'm studing this webpage, working thorough the OSPF configurations described above, and I get stuck on the concept of "link count" under "Router Link States" found in the output of show ip ospf database
The structure of the notes above is helpful, because I was tracking the state of each router BEFORE i made changes to the subsquent router. But just to be sure, today I decided to recreate the topology, then configure each router one at a time, noting the results as I went.
And I ran into some problems.
Here is the original topology:
And today's recreated toplogy:
After replicating the toplogy and programming the IP addresses on each router, I started on configurations, just like before:
LabA
LabA(config)# router ospf 100
LabA(config-router)# net 172.16.10.1 0.0.0.0 area 0
[no output]
LabA# show ip ospf neighbor
[no output]
LabA# show ip ospf database
OSPF Router with ID (172.16.10.1) (Process ID 100)
Router Link States (Area 0)
Link ID ADV Router Age Seq# Checksum Link count
172.16.10.1 172.16.10.1 44 0x80000001 0x00b24b 1
LabA# show ip ospf interface
FastEthernet0/0 is up, line protocol is up
Internet address is 172.16.10.1/24, Area 0
Process ID 100, Router ID 172.16.10.1, Network Type BROADCAST, Cost: 1
Transmit Delay is 1 sec, State DR, Priority 1
Designated Router (ID) 172.16.10.1, Interface address 172.16.10.1
No backup designated router on this network
Timer intervals configured, Hello 10, Dead 40, Wait 40, Retransmit 5
Hello due in 00:00:08
Index 1/1, flood queue length 0
Next 0x0(0)/0x0(0)
Last flood scan length is 1, maximum is 1
Last flood scan time is 0 msec, maximum is 0 msec
Neighbor Count is 0, Adjacent neighbor count is 0
Suppress hello for 0 neighbor(s)
good so far.... On to LabB router
LabB
LabB(config)# router ospf 101
LabB(config-router)# net 172.16.10.2 0.0.0.0 area 0
LabB(config-router)# net 172.16.20.1 0.0.0.0 area 0
01:26:36: %OSPF-5-ADJCHG: Process 101, Nbr 172.16.10.1
on FastEthernet0/0 from LOADING to FULL, Loading Done
LabB# show ip ospf neighbor
Neighbor ID Pri State Dead Time Address Interface
172.16.10.1 1 FULL/DR 00:00:33 172.16.10.1
LabB# show ip ospf database
OSPF Router with ID (172.16.20.1) (Process ID 101)
Router Link States (Area 0)
Link ID ADV Router Age Seq# Checksum Link count
172.16.10.1 172.16.10.1 145 0x80000002 0x0067cd 1
172.16.20.1 172.16.20.1 32 0x80000003 0x006e8f 2
Net Link States (Area 0)
Link ID ADV Router Age Seq# Checksum
172.16.10.1 172.16.10.1 145 0x80000001 0x00953d
LabB# show ip ospf interface
FastEthernet0/0 is up, line protocol is up
Internet address is 172.16.10.2/24, Area 0
Process ID 101, Router ID 172.16.20.1, Network Type BROADCAST, Cost: 1
Transmit Delay is 1 sec, State BDR, Priority 1
Designated Router (ID) 172.16.10.1, Interface address 172.16.10.1
Backup Designated Router (ID) 172.16.20.1, Interface address 172.16.10.2
Timer intervals configured, Hello 10, Dead 40, Wait 40, Retransmit 5
Hello due in 00:00:03
Index 1/1, flood queue length 0
Next 0x0(0)/0x0(0)
Last flood scan length is 1, maximum is 1
Last flood scan time is 0 msec, maximum is 0 msec
Neighbor Count is 1, Adjacent neighbor count is 1
Adjacent with neighbor 172.16.10.1 (Designated Router)
Suppress hello for 0 neighbor(s)
Serial0/0/0 is up, line protocol is up
Internet address is 172.16.20.1/24, Area 0
Process ID 101, Router ID 172.16.20.1, Network Type POINT-TO-POINT, Cost: 64
Transmit Delay is 1 sec, State POINT-TO-POINT,
Timer intervals configured, Hello 10, Dead 40, Wait 40, Retransmit 5
Hello due in 00:00:04
Index 2/2, flood queue length 0
Next 0x0(0)/0x0(0)
Last flood scan length is 1, maximum is 1
Last flood scan time is 0 msec, maximum is 0 msec
Suppress hello for 0 neighbor(s)
still looks good; same as before.... On to LabC router
LabC
LabC(config)# router ospf 102
LabC(config-router)# net 172.16.20.2 0.0.0.0 area 0
LabC(config-router)# net 172.16.30.1 0.0.0.0 area 0
LabC(config-router)# net 172.16.40.1 0.0.0.0 area 0
01:33:54: %OSPF-5-ADJCHG: Process 102, Nbr 172.16.20.1
on Serial0/0/0 from LOADING to FULL, Loading Done
LabC# show ip ospf neighbor
[no output]
And here is where I ran into trouble. The show ip ospf neighbor command returns nothing. How can that be?
After awhile I realized it is due to a misconfiguration in the topology.
For Lab C, I programmed the interfaces as follows:
LabC(config)# int f0/0
LabC(config-if)# ip addr 172.16.30.1 255.255.255.0
LabC(config-if)# no shut
LabC(config-if)# int s0/0/0
LabC(config-if)# ip addr 172.16.20.2 255.255.255.0
LabC(config-if)# no shut
LabC(config-if)# int s0/0/1
LabC(config-if)# ip addr 172.16.40.1 255.255.255.0
LabC(config-if)# no shut
but here is what it SHOULD HAVE looked like (as it did the first time I built it)
S0/0/0 and S0/0/1 are swapped. When I gave the IP 172.16.20.2 to s/0/0/0, thinking that was the interface on the left side which faces Lab B, I was actually giving 172.16.20.2 to the right side, facing LabC (which has no OSPF configs yet.)
Since the left side got got the IP intended for the right side which was 172.16.40.1
the inverse also occured-
the right side got the IP intended for the left which was 172.16.20.2
LabC left side should have been
s0/0/0 with 20.2
and LabC right side should have been
s0/0/1 with 40.1
The correct IPs were mapped to the correct interfaces. But the mistake happened before I even programmed them.
When I made the connections from LabB to LabC and from LabD to LabC, I plugged then into the wrong ports.
Interestingly.. not only is this causing OSPF to not see B as a neighbor from C.. but B and C cannot ping eachother either.
@B the config is 172.16.20.1/24 @ S0/0/0
@C the config is 172.16.40.1/24 @ S/0/0/1
meaning they are not even on the same network! But the system is not throwing any errors or bringing it to my attention. It just fails to connect.
To correct the issue, I simply deleted those two links and re-created them. Worth noting, I used the auto select cable here, which does not ask which interface you want to use when attaching. Earlier I must have plugged the right side first, and auto select plugged into 0/0/0.
This time I plugged into left side first.
Now LabC OSPF data is reading out correctly...
LabC
LabC(config)# router ospf 102
LabC(config-router)# net 172.16.20.2 0.0.0.0 area 0
LabC(config-router)# net 172.16.30.1 0.0.0.0 area 0
LabC(config-router)# net 172.16.40.1 0.0.0.0 area 0
01:33:54: %OSPF-5-ADJCHG: Process 102, Nbr 172.16.20.1
on Serial0/0/0 from LOADING to FULL, Loading Done
LabC# show ip ospf neighbor
Neighbor ID Pri State Dead Time Address Interface
172.16.20.1 0 FULL/ - 00:00:30 172.16.20.1 Serial0/0/0
LabC# show ip ospf database
OSPF Router with ID (172.16.40.1) (Process ID 102)
Router Link States (Area 0)
Link ID ADV Router Age Seq# Checksum Link count
172.16.10.1 172.16.10.1 542 0x80000002 0x0067cd 1
172.16.20.1 172.16.20.1 90 0x80000004 0x00a551 3
172.16.40.1 172.16.40.1 37 0x80000004 0x00e47c 4
Net Link States (Area 0)
Link ID ADV Router Age Seq# Checksum
172.16.10.1 172.16.10.1 542 0x80000001 0x00953d
LabC# show ip ospf interface
Serial0/0/0 is up, line protocol is up
Internet address is 172.16.20.2/24, Area 0
Process ID 102, Router ID 172.16.40.1, Network Type POINT-TO-POINT, Cost: 64
Transmit Delay is 1 sec, State POINT-TO-POINT,
Timer intervals configured, Hello 10, Dead 40, Wait 40, Retransmit 5
Hello due in 00:00:01
Index 1/1, flood queue length 0
Next 0x0(0)/0x0(0)
Last flood scan length is 1, maximum is 1
Last flood scan time is 0 msec, maximum is 0 msec
Neighbor Count is 1 , Adjacent neighbor count is 1
Adjacent with neighbor 172.16.20.1
Suppress hello for 0 neighbor(s)
FastEthernet0/0 is up, line protocol is up
Internet address is 172.16.30.1/24, Area 0
Process ID 102, Router ID 172.16.40.1, Network Type BROADCAST, Cost: 1
Transmit Delay is 1 sec, State DR, Priority 1
Designated Router (ID) 172.16.40.1, Interface address 172.16.30.1
No backup designated router on this network
Timer intervals configured, Hello 10, Dead 40, Wait 40, Retransmit 5
Hello due in 00:00:02
Index 2/2, flood queue length 0
Next 0x0(0)/0x0(0)
Last flood scan length is 1, maximum is 1
Last flood scan time is 0 msec, maximum is 0 msec
Neighbor Count is 0, Adjacent neighbor count is 0
Suppress hello for 0 neighbor(s)
Serial0/0/1 is up, line protocol is up
Internet address is 172.16.40.1/24, Area 0
Process ID 102, Router ID 172.16.40.1, Network Type POINT-TO-POINT, Cost: 64
Transmit Delay is 1 sec, State POINT-TO-POINT,
Timer intervals configured, Hello 10, Dead 40, Wait 40, Retransmit 5
Hello due in 00:00:08
Index 3/3, flood queue length 0
Next 0x0(0)/0x0(0)
Last flood scan length is 1, maximum is 1
Last flood scan time is 0 msec, maximum is 0 msec
Suppress hello for 0 neighbor(s)
Which brings me to the original reason I re-created this topology... I was confused about the LINK COUNTS here:
OSPF Router with ID (172.16.40.1) (Process ID 102)
Router Link States (Area 0)
Link ID ADV Router Age Seq# Checksum Link count
172.16.10.1 172.16.10.1 542 0x80000002 0x0067cd 1
172.16.20.1 172.16.20.1 90 0x80000004 0x00a551 3
172.16.40.1 172.16.40.1 37 0x80000004 0x00e47c 4
Net Link States (Area 0)
Link ID ADV Router Age Seq# Checksum
172.16.10.1 172.16.10.1 542 0x80000001 0x00953d
The steps of recreating the lab were helpful, but this link answered the question:
Here is the output of each router's command show ip ospf interface as they are set up one at a time.
LabA - No OSPF at B, C, or D yet
show ip ospf database
OSPF Router with ID (172.16.10.1) (Process ID 100)
Router Link States (Area 0)
Link ID ADV Router Age Seq# Checksum Link count
172.16.10.1 172.16.10.1 44 0x80000001 0x00b24b 1
LabB - No OSPF at C or D yet
show ip ospf database
OSPF Router with ID (172.16.20.1) (Process ID 101)
Router Link States (Area 0)
Link ID ADV Router Age Seq# Checksum Link count
172.16.10.1 172.16.10.1 145 0x80000002 0x0067cd 1
172.16.20.1 172.16.20.1 32 0x80000003 0x006e8f 2
Net Link States (Area 0)
Link ID ADV Router Age Seq# Checksum
172.16.10.1 172.16.10.1 145 0x80000001 0x00953d
the 20.2 interface on this router has 2 ospf links.
The left-facing out to RA, a crossover cable
The right-facing out to RC, a serial cable.
If the solution I found is correct, why is this serial link not being counted twice? The solution (I think) is revealed after the configuration of the next router...
LabC - No OSPF at D yet
show ip ospf database
OSPF Router with ID (172.16.40.1) (Process ID 102)
Router Link States (Area 0)
Link ID ADV Router Age Seq# Checksum Link count
172.16.10.1 172.16.10.1 542 0x80000002 0x0067cd 1
172.16.20.1 172.16.20.1 90 0x80000004 0x00a551 3
172.16.40.1 172.16.40.1 37 0x80000004 0x00e47c 4
Net Link States (Area 0)
Link ID ADV Router Age Seq# Checksum
172.16.10.1 172.16.10.1 542 0x80000001 0x00953d
NOW we can see that the 20.1 link, which is the right-facing interface on LabB.. aka the router ID..
has THREE OSPF links.
Nothing changed on the left side of B. But on the right side, we now have an active OSPF router at the other end of the link. This leads me to believe that the forum post was correct that 'serial links are counted twice', but, more specifically, BOTH ENDS of the serial(PPP) link are counted... IF there is an OSPF router on each end.
This is backed up by the fact that LabC, OSPF id 40.1, has four OSPF links. The top-facing link to the 30 network DOES count.. even though it has no OSPF router on the other end. It counts because it's not a serial link.
The requirement of having an OSPF router on the other end for an interface to count here, only applies to serial links. And pertains to BOTH ends of the link being counted.
In LabC's case, we have one serial at left, being counted twice. One ethernet at top, being counted once. And one serial at right only being counted once because LabD is not active with OSPF yet.
If this is correct, then we should see Lab C's 40.1 count go to 5 after LabD is set for OSPF....
LabD - all 4 routers have OSPF
show ip ospf database
OSPF Router with ID (172.16.50.1) (Process ID 103)
Router Link States (Area 0)
Link ID ADV Router Age Seq# Checksum Link count
172.16.10.1 172.16.10.1 785 0x80000002 0x0067cd 1
172.16.20.1 172.16.20.1 333 0x80000004 0x00a551 3
172.16.40.1 172.16.40.1 111 0x80000005 0x00013b 5
172.16.50.1 172.16.50.1 53 0x80000003 0x001023 3
Net Link States (Area 0)
Link ID ADV Router Age Seq# Checksum
172.16.10.1 172.16.10.1 785 0x80000001 0x00953d
and back to LabC.....
show ip ospf database
OSPF Router with ID (172.16.40.1) (Process ID 102)
Router Link States (Area 0)
Link ID ADV Router Age Seq# Checksum Link count
172.16.10.1 172.16.10.1 1174 0x80000002 0x0067cd 1
172.16.20.1 172.16.20.1 722 0x80000004 0x00a551 3
172.16.40.1 172.16.40.1 500 0x80000005 0x00013b 5
172.16.50.1 172.16.50.1 441 0x80000003 0x001023 3
Net Link States (Area 0)
Link ID ADV Router Age Seq# Checksum
172.16.10.1 172.16.10.1 1174 0x80000001 0x00953d
Looks good! The link count for each router makes sense if you count the serial interfaces twice (one for each end).
the OSPF databases now match across all 4 routers.
NOTE that this is a database of routers, identified by router ID. It is not a topology that lists routers AND routes, like in the "equivalent" eigrp command show eigrp topology
Note that the .30 network is NOT represented here.
LabA# show ip ospf database
OSPF Router with ID (172.16.10.1) (Process ID 100)
Router Link States (Area 0)
Link ID ADV Router Age Seq# Checksum Link count
172.16.10.1 172.16.10.1 1138 0x80000002 0x0067cd 1
172.16.20.1 172.16.20.1 686 0x80000004 0x00a551 3
172.16.40.1 172.16.40.1 463 0x80000005 0x00013b 5
172.16.50.1 172.16.50.1 404 0x80000003 0x001023 3
Net Link States (Area 0)
Link ID ADV Router Age Seq# Checksum
172.16.10.1 172.16.10.1 1138 0x80000001 0x00953d
LabB# show ip ospf database
OSPF Router with ID (172.16.20.1) (Process ID 101)
Router Link States (Area 0)
Link ID ADV Router Age Seq# Checksum Link count
172.16.10.1 172.16.10.1 1151 0x80000002 0x0067cd 1
172.16.20.1 172.16.20.1 699 0x80000004 0x00a551 3
172.16.40.1 172.16.40.1 476 0x80000005 0x00013b 5
172.16.50.1 172.16.50.1 417 0x80000003 0x001023 3
Net Link States (Area 0)
Link ID ADV Router Age Seq# Checksum
172.16.10.1 172.16.10.1 1151 0x80000001 0x00953d
LabC# show ip ospf database
OSPF Router with ID (172.16.40.1) (Process ID 102)
Router Link States (Area 0)
Link ID ADV Router Age Seq# Checksum Link count
172.16.10.1 172.16.10.1 1174 0x80000002 0x0067cd 1
172.16.20.1 172.16.20.1 722 0x80000004 0x00a551 3
172.16.40.1 172.16.40.1 500 0x80000005 0x00013b 5
172.16.50.1 172.16.50.1 441 0x80000003 0x001023 3
Net Link States (Area 0)
Link ID ADV Router Age Seq# Checksum
172.16.10.1 172.16.10.1 1174 0x80000001 0x00953d
LabD# show ip ospf database
OSPF Router with ID (172.16.50.1) (Process ID 103)
Router Link States (Area 0)
Link ID ADV Router Age Seq# Checksum Link count
172.16.10.1 172.16.10.1 785 0x80000002 0x0067cd 1
172.16.20.1 172.16.20.1 333 0x80000004 0x00a551 3
172.16.40.1 172.16.40.1 111 0x80000005 0x00013b 5
172.16.50.1 172.16.50.1 53 0x80000003 0x001023 3
Net Link States (Area 0)
Link ID ADV Router Age Seq# Checksum
172.16.10.1 172.16.10.1 785 0x80000001 0x00953d
Below is our routing tables with OSPF data. We do see the .30 network here.
Everyone can reach it:
LabA via LabB's 10.2
LabB via LabC's 20.2
LabC via direct connection
LabD via LabC's 40.1
LabA# show ip route
172.16.0.0/16 is variably subnetted, 6 subnets, 2 masks
C 172.16.10.0/24 is directly connected, FastEthernet0/0
L 172.16.10.1/32 is directly connected, FastEthernet0/0
O 172.16.20.0/24 [110/65] via 172.16.10.2, 00:28:03, FastEthernet0/0
O 172.16.30.0/24 [110/66] via 172.16.10.2, 00:21:35, FastEthernet0/0
O 172.16.40.0/24 [110/129] via 172.16.10.2, 00:21:25, FastEthernet0/0
O 172.16.50.0/24 [110/130] via 172.16.10.2, 00:17:40, FastEthernet0/0
LabB# show ip route
172.16.0.0/16 is variably subnetted, 7 subnets, 2 masks
C 172.16.10.0/24 is directly connected, FastEthernet0/0
L 172.16.10.2/32 is directly connected, FastEthernet0/0
C 172.16.20.0/24 is directly connected, Serial0/0/0
L 172.16.20.1/32 is directly connected, Serial0/0/0
O 172.16.30.0/24 [110/65] via 172.16.20.2, 00:27:04, Serial0/0/0
O 172.16.40.0/24 [110/128] via 172.16.20.2, 00:26:54, Serial0/0/0
O 172.16.50.0/24 [110/129] via 172.16.20.2, 00:23:09, Serial0/0/0
LabC# show ip route
172.16.0.0/16 is variably subnetted, 8 subnets, 2 masks
O 172.16.10.0/24 [110/65] via 172.16.20.1, 00:27:52, Serial0/0/0
C 172.16.20.0/24 is directly connected, Serial0/0/0
L 172.16.20.2/32 is directly connected, Serial0/0/0
C 172.16.30.0/24 is directly connected, FastEthernet0/0
L 172.16.30.1/32 is directly connected, FastEthernet0/0
C 172.16.40.0/24 is directly connected, Serial0/0/1
L 172.16.40.1/32 is directly connected, Serial0/0/1
O 172.16.50.0/24 [110/65] via 172.16.40.2, 00:23:36, Serial0/0/1
LabD# show ip route
172.16.0.0/16 is variably subnetted, 7 subnets, 2 masks
O 172.16.10.0/24 [110/129] via 172.16.40.1, 00:25:20, Serial0/0/0
O 172.16.20.0/24 [110/128] via 172.16.40.1, 00:25:20, Serial0/0/0
O 172.16.30.0/24 [110/65] via 172.16.40.1, 00:25:20, Serial0/0/0
C 172.16.40.0/24 is directly connected, Serial0/0/0
L 172.16.40.2/32 is directly connected, Serial0/0/0
C 172.16.50.0/24 is directly connected, FastEthernet0/0
L 172.16.50.1/32 is directly connected, FastEthernet0/0
moving on.......
9.5 - OSPF DR and BDR Elections
EachRouter(config)# hostname X (A, B, or C)
EachRouter(config)# line con 0
EachRouter(config-line)# exec-timeout 0 0
A(config)# int f0/0
A(config-if)# ip addr 10.1.1.1 255.255.255.0
A(config-if)# no shut
A(config)# router ospf 12345
A(config-router)# net 10.1.1.0 0.0.0.255 area 0
00:23:30: %OSPF-5-ADJCHG: Process 12345, Nbr 10.1.1.3 on FastEthernet0/0 from LOADING to FULL, Loading Done
00:23:30: %OSPF-5-ADJCHG: Process 12345, Nbr 10.1.1.2 on FastEthernet0/0 from LOADING to FULL, Loading Done
A# show ip ospf int note this output was generated AFTER all 3 routers set for OSPF
FastEthernet0/0 is up, line protocol is up
Internet address is 10.1.1.1/24, Area 0
Process ID 12345, Router ID 10.1.1.1, Network Type BROADCAST, Cost: 1
Transmit Delay is 1 sec, State DROTHER, Priority 1
Designated Router (ID) 10.1.1.3, Interface address 10.1.1.3
Backup Designated Router (ID) 10.1.1.2, Interface address 10.1.1.2
Timer intervals configured, Hello 10, Dead 40, Wait 40, Retransmit 5
Hello due in 00:00:04
Index 1/1, flood queue length 0
Next 0x0(0)/0x0(0)
Last flood scan length is 1, maximum is 1
Last flood scan time is 0 msec, maximum is 0 msec
Neighbor Count is 2, Adjacent neighbor count is 2
Adjacent with neighbor 10.1.1.3 (Designated Router)
Adjacent with neighbor 10.1.1.2 (Backup Designated Router)
Suppress hello for 0 neighbor(s)
A(config-if)#shut
A(config-if)#
%LINK-5-CHANGED: Interface FastEthernet0/0, changed state to administratively down
%LINEPROTO-5-UPDOWN: Line protocol on Interface FastEthernet0/0, changed state to down
00:40:28: %OSPF-5-ADJCHG: Process 12345, Nbr 10.1.1.2 on FastEthernet0/0 from FULL to DOWN, Neighbor Down: Interface down or detached
00:40:28: OSPF: Build router LSA for area 0, router ID 10.1.1.1, seq 0xffffffff80000003
00:40:28: %OSPF-5-ADJCHG: Process 12345, Nbr 10.1.1.3 on FastEthernet0/0 from FULL to DOWN, Neighbor Down: Interface down or detached
00:40:28: OSPF: Build router LSA for area 0, router ID 10.1.1.1, seq 0xffffffff80000004
00:40:28: OSPF: Build router LSA for area 0, router ID 10.1.1.1, seq 0xffffffff80000004
A(config-if)#no shut
A(config-if)#
%LINK-5-CHANGED: Interface FastEthernet0/0, changed state to up
%LINEPROTO-5-UPDOWN: Line protocol on Interface FastEthernet0/0, changed state to up
00:40:48: OSPF: Build router LSA for area 0, router ID 10.1.1.1, seq 0xffffffff80000004
00:41:27: OSPF: Backup seen Event before WAIT timer on FastEthernet0/0
00:41:27: OSPF: DR/BDR election on FastEthernet0/0
00:41:27: OSPF: Elect BDR 10.1.1.2
00:41:27: OSPF: Elect DR 10.1.1.3
00:41:27: DR: 10.1.1.3 (Id) BDR: 10.1.1.2 (Id)
00:41:27: OSPF: Send DBD to 10.1.1.3 on FastEthernet0/0 seq 0x5accb8e2 opt 0x00 flag 0x7 len 32
B(config)# int f0/0
B(config-if)# ip addr 10.1.1.2 255.255.255.0
B(config-if)# no shut
B(config)# router ospf 12345
B(config-router)# net 10.1.1.0 0.0.0.255 area 0
00:23:29: %OSPF-5-ADJCHG: Process 12345, Nbr 10.1.1.3 on FastEthernet0/0 from LOADING to FULL, Loading Done
00:23:29: %OSPF-5-ADJCHG: Process 12345, Nbr 10.1.1.1 on FastEthernet0/0 from LOADING to FULL, Loading Done
B# show ip ospf int note this output was generated AFTER all 3 routers set for OSPF
FastEthernet0/0 is up, line protocol is up
Internet address is 10.1.1.2/24, Area 0
Process ID 12345, Router ID 10.1.1.2, Network Type BROADCAST, Cost: 1
Transmit Delay is 1 sec, State BDR, Priority 1
Designated Router (ID) 10.1.1.3, Interface address 10.1.1.3
Backup Designated Router (ID) 10.1.1.2, Interface address 10.1.1.2
Timer intervals configured, Hello 10, Dead 40, Wait 40, Retransmit 5
Hello due in 00:00:05
Index 1/1, flood queue length 0
Next 0x0(0)/0x0(0)
Last flood scan length is 1, maximum is 1
Last flood scan time is 0 msec, maximum is 0 msec
Neighbor Count is 2, Adjacent neighbor count is 2
Adjacent with neighbor 10.1.1.1
Adjacent with neighbor 10.1.1.3 (Designated Router)
Suppress hello for 0 neighbor(s)
B#debug ip ospf adj
OSPF adjacency events debugging is on
B#
00:39:21: OSPF: DR/BDR election on FastEthernet0/0
00:39:21: OSPF: Elect BDR 10.1.1.2
00:39:21: OSPF: Elect DR 10.1.1.3
00:39:21: DR: 10.1.1.3 (Id) BDR: 10.1.1.2 (Id)
00:41:01: %OSPF-5-ADJCHG: Process 12345, Nbr 10.1.1.1 on FastEthernet0/0 from FULL to DOWN, Neighbor Down: Dead timer expired
00:41:01: %OSPF-5-ADJCHG: Process 12345, Nbr 10.1.1.1 on FastEthernet0/0 from FULL to DOWN, Neighbor Down: Interface down or detached
00:41:01: OSPF: Build router LSA for area 0, router ID 10.1.1.2, seq 0xffffffff80000003
00:41:01: OSPF: DR/BDR election on FastEthernet0/0
00:41:01: OSPF: Elect BDR 10.1.1.2
00:41:01: OSPF: Elect DR 10.1.1.3
C(config)# int f0/0
C(config-if)# ip addr 10.1.1.3 255.255.255.0
C(config-if)# no shut
C(config)# router ospf 12345
C(config-router)# net 10.1.1.0 0.0.0.255 area 0
00:23:27: %OSPF-5-ADJCHG: Process 12345, Nbr 10.1.1.1 on FastEthernet0/0 from LOADING to FULL, Loading Done
00:23:27: %OSPF-5-ADJCHG: Process 12345, Nbr 10.1.1.2 on FastEthernet0/0 from LOADING to FULL, Loading Done
C# show ip ospf int note this output was generated AFTER all 3 routers set for OSPF
FastEthernet0/0 is up, line protocol is up
Internet address is 10.1.1.3/24, Area 0
Process ID 12345, Router ID 10.1.1.3, Network Type BROADCAST, Cost: 1
Transmit Delay is 1 sec, State DR, Priority 1
Designated Router (ID) 10.1.1.3, Interface address 10.1.1.3
Backup Designated Router (ID) 10.1.1.2, Interface address 10.1.1.2
Timer intervals configured, Hello 10, Dead 40, Wait 40, Retransmit 5
Hello due in 00:00:00
Index 1/1, flood queue length 0
Next 0x0(0)/0x0(0)
Last flood scan length is 1, maximum is 1
Last flood scan time is 0 msec, maximum is 0 msec
Neighbor Count is 2, Adjacent neighbor count is 2
Adjacent with neighbor 10.1.1.1
Adjacent with neighbor 10.1.1.2 (Backup Designated Router)
Suppress hello for 0 neighbor(s)
C#debug ip ospf adj
OSPF adjacency events debugging is on
C#
00:39:19: OSPF: DR/BDR election on FastEthernet0/0
00:39:19: OSPF: Elect BDR 10.1.1.2
00:39:19: OSPF: Elect DR 10.1.1.3
00:39:19: DR: 10.1.1.3 (Id) BDR: 10.1.1.2 (Id)
00:40:59: %OSPF-5-ADJCHG: Process 12345, Nbr 10.1.1.1 on FastEthernet0/0 from FULL to DOWN, Neighbor Down: Dead timer expired
00:40:59: %OSPF-5-ADJCHG: Process 12345, Nbr 10.1.1.1 on FastEthernet0/0 from FULL to DOWN, Neighbor Down: Interface down or detached
00:40:59: OSPF: Build router LSA for area 0, router ID 10.1.1.3, seq 0xffffffff80000003
00:40:59: OSPF: Build net LSA for area 0, router ID 10.1.1.3, seq 0xffffffff80000003
00:40:59: OSPF: DR/BDR election on FastEthernet0/0
00:40:59: OSPF: Elect BDR 10.1.1.2
00:40:59: OSPF: Elect DR 10.1.1.3
DR and BDR automtically set based on higest IP address
Note our network type is BROADCAST because we're using ethernet interfaces...
it would be point-to-point if using a serial connection
we want to manually overide the priority of the router. ZERO priority means it wont participate in the election process
MAX priority of 255 means no other router can beat it for DR
We'll set the priority for router A to 3.
It will beome the DR only after we shut/no shut the interface router
AND
manually power on/off the other two routers
A(config)# int f0/0
A(config-int)# ip ospf priority 3
A(config-int)# shut
A(config-int)# no shut
A# debug ip ospf adj
B# debug ip ospf adj
00:05:50: OSPF: DR/BDR election on FastEthernet0/0
00:05:50: OSPF: Elect BDR 10.1.1.2
00:05:50: OSPF: Elect DR 10.1.1.1
00:05:50: OSPF: Elect BDR 10.1.1.2
00:05:50: OSPF: Elect DR 10.1.1.1
00:05:50: DR: 10.1.1.1 (Id) BDR: 10.1.1.2 (Id)
00:05:50: OSPF: Send DBD to 10.1.1.1 on FastEthernet0/0 seq 0x10164ebb opt 0x00 flag 0x7 len 32
00:05:50: OSPF: Build router LSA for area 0, router ID 10.1.1.2, seq 0xffffffff80000002
00:05:52: OSPF: Rcv DBD from 10.1.1.1 on FastEthernet0/0 seq 0x20368093 opt 0x00 flag 0x7 len 32 mtu 1500 state EXSTART
00:05:52: OSPF: First DBD and we are not SLAVE
00:05:55: OSPF: Send DBD to 10.1.1.1 on FastEthernet0/0 seq 0x10164ebb opt 0x00 flag 0x7 len 32
00:05:55: OSPF: Rcv DBD from 10.1.1.1 on FastEthernet0/0 seq 0x10164ebb opt 0x00 flag 0x2 len 112 mtu 1500 state EXSTART
00:05:55: OSPF: NBR Negotiation Done. We are the MASTER
00:05:55: OSPF: Send DBD to 10.1.1.1 on FastEthernet0/0 seq 0x10164ebc opt 0x00 flag 0x3 len 52
00:05:55: OSPF: Rcv DBD from 10.1.1.1 on FastEthernet0/0 seq 0x10164ebc opt 0x00 flag 0x0 len 32 mtu 1500 state EXCHANGE
00:05:55: OSPF: Send DBD to 10.1.1.1 on FastEthernet0/0 seq 0x10164ebd opt 0x00 flag 0x1 len 32
00:05:55: OSPF: Rcv DBD from 10.1.1.1 on FastEthernet0/0 seq 0x10164ebd opt 0x00 flag 0x0 len 32 mtu 1500 state EXCHANGE
00:05:55: Exchange Done with 10.1.1.1 on FastEthernet0/0
00:05:55: OSPF: Database request to 10.1.1.1
00:05:55: OSPF: sent LS REQ packet to 10.1.1.1, length 36
00:05:55: OSPF: Rcv DBD from 10.1.1.1 on FastEthernet0/0 seq 0x10164ebd opt 0x00 flag 0x0 len 32 mtu 1500 state LOADING
00:05:55: Synchronized with with 10.1.1.1 on FastEthernet0/0, state FULL
00:05:55: %OSPF-5-ADJCHG: Process 12345, Nbr 10.1.1.1 on FastEthernet0/0 from LOADING to FULL, Loading Done
00:05:55: OSPF: Build router LSA for area 0, router ID 10.1.1.2, seq 0xffffffff80000002
C# debug ip ospf adj
00:06:13: OSPF: DR/BDR election on FastEthernet0/0
00:06:13: OSPF: Elect BDR 10.1.1.2
00:06:13: OSPF: Elect DR 10.1.1.1
00:06:13: DR: 10.1.1.1 (Id) BDR: 10.1.1.2 (Id)
00:06:13: OSPF: Send DBD to 10.1.1.1 on FastEthernet0/0 seq 0x1cc5536d opt 0x00 flag 0x7 len 32
00:06:13: OSPF: Send DBD to 10.1.1.2 on FastEthernet0/0 seq 0x3d51ca66 opt 0x00 flag 0x7 len 32
00:06:13: OSPF: Build router LSA for area 0, router ID 10.1.1.3, seq 0xffffffff80000002
00:06:17: OSPF: Rcv DBD from 10.1.1.1 on FastEthernet0/0 seq 0x6b532eec opt 0x00 flag 0x7 len 32 mtu 1500 state EXSTART
00:06:17: OSPF: First DBD and we are not SLAVE
00:06:17: OSPF: Rcv DBD from 10.1.1.2 on FastEthernet0/0 seq 0x783110f4 opt 0x00 flag 0x7 len 32 mtu 1500 state EXSTART
00:06:17: OSPF: First DBD and we are not SLAVE
00:06:18: OSPF: Send DBD to 10.1.1.2 on FastEthernet0/0 seq 0x3d51ca66 opt 0x00 flag 0x7 len 32
00:06:18: OSPF: Send DBD to 10.1.1.1 on FastEthernet0/0 seq 0x1cc5536d opt 0x00 flag 0x7 len 32
00:06:18: OSPF: Rcv DBD from 10.1.1.2 on FastEthernet0/0 seq 0x3d51ca66 opt 0x00 flag 0x2 len 132 mtu 1500 state EXSTART
00:06:18: OSPF: NBR Negotiation Done. We are the MASTER
00:06:18: OSPF: Send DBD to 10.1.1.2 on FastEthernet0/0 seq 0x3d51ca67 opt 0x00 flag 0x3 len 52
00:06:18: OSPF: Rcv DBD from 10.1.1.1 on FastEthernet0/0 seq 0x1cc5536d opt 0x00 flag 0x2 len 132 mtu 1500 state EXSTART
00:06:18: OSPF: NBR Negotiation Done. We are the MASTER
00:06:18: OSPF: Send DBD to 10.1.1.1 on FastEthernet0/0 seq 0x1cc5536e opt 0x00 flag 0x3 len 52
00:06:18: OSPF: Rcv DBD from 10.1.1.2 on FastEthernet0/0 seq 0x3d51ca67 opt 0x00 flag 0x0 len 32 mtu 1500 state EXCHANGE
00:06:18: OSPF: Send DBD to 10.1.1.2 on FastEthernet0/0 seq 0x3d51ca68 opt 0x00 flag 0x1 len 32
00:06:18: OSPF: Rcv DBD from 10.1.1.1 on FastEthernet0/0 seq 0x1cc5536e opt 0x00 flag 0x0 len 32 mtu 1500 state EXCHANGE
00:06:18: OSPF: Send DBD to 10.1.1.1 on FastEthernet0/0 seq 0x1cc5536f opt 0x00 flag 0x1 len 32
00:06:18: OSPF: Rcv DBD from 10.1.1.2 on FastEthernet0/0 seq 0x3d51ca68 opt 0x00 flag 0x0 len 32 mtu 1500 state EXCHANGE
00:06:18: Exchange Done with 10.1.1.2 on FastEthernet0/0
00:06:18: OSPF: Database request to 10.1.1.2
00:06:18: OSPF: sent LS REQ packet to 10.1.1.2, length 48
00:06:18: OSPF: Rcv DBD from 10.1.1.1 on FastEthernet0/0 seq 0x1cc5536f opt 0x00 flag 0x0 len 32 mtu 1500 state EXCHANGE
A# show ip ospf interface f0/0
FastEthernet0/0 is up, line protocol is up
Internet address is 10.1.1.1/24, Area 0
Process ID 12345, Router ID 10.1.1.1, Network Type BROADCAST, Cost: 1
Transmit Delay is 1 sec, State DR, Priority 3
Designated Router (ID) 10.1.1.1, Interface address 10.1.1.1
Backup Designated Router (ID) 10.1.1.2, Interface address 10.1.1.2
Timer intervals configured, Hello 10, Dead 40, Wait 40, Retransmit 5
Hello due in 00:00:09
Index 1/1, flood queue length 0
Next 0x0(0)/0x0(0)
Last flood scan length is 1, maximum is 1
Last flood scan time is 0 msec, maximum is 0 msec
Neighbor Count is 2, Adjacent neighbor count is 2
Adjacent with neighbor 10.1.1.2 (Backup Designated Router)
Adjacent with neighbor 10.1.1.3
Suppress hello for 0 neighbor(s)
A# show ip ospf neighbor
Neighbor ID Pri State Dead Time Address Interface
10.1.1.2 1 FULL/BDR 00:00:37 10.1.1.2 FastEthernet0/0
10.1.1.3 1 FULL/DROTHER 00:00:30 10.1.1.3 FastEthernet0/0
B# show ip ospf interface f0/0
FastEthernet0/0 is up, line protocol is up
Internet address is 10.1.1.2/24, Area 0
Process ID 12345, Router ID 10.1.1.2, Network Type BROADCAST, Cost: 1
Transmit Delay is 1 sec, State BDR, Priority 1
Designated Router (ID) 10.1.1.1, Interface address 10.1.1.1
Backup Designated Router (ID) 10.1.1.2, Interface address 10.1.1.2
Timer intervals configured, Hello 10, Dead 40, Wait 40, Retransmit 5
Hello due in 00:00:08
Index 1/1, flood queue length 0
Next 0x0(0)/0x0(0)
Last flood scan length is 1, maximum is 1
Last flood scan time is 0 msec, maximum is 0 msec
Neighbor Count is 2, Adjacent neighbor count is 2
Adjacent with neighbor 10.1.1.1 (Designated Router)
Adjacent with neighbor 10.1.1.3
Suppress hello for 0 neighbor(s)
B# show ip ospf neighbor
Neighbor ID Pri State Dead Time Address Interface
10.1.1.1 3 FULL/DR 00:00:35 10.1.1.1 FastEthernet0/0
10.1.1.3 1 FULL/DROTHER 00:00:31 10.1.1.3 FastEthernet0/0
C# show ip ospf interface f0/0
FastEthernet0/0 is up, line protocol is up
Internet address is 10.1.1.3/24, Area 0
Process ID 12345, Router ID 10.1.1.3, Network Type BROADCAST, Cost: 1
Transmit Delay is 1 sec, State DROTHER, Priority 1
Designated Router (ID) 10.1.1.1, Interface address 10.1.1.1
Backup Designated Router (ID) 10.1.1.2, Interface address 10.1.1.2
Timer intervals configured, Hello 10, Dead 40, Wait 40, Retransmit 5
Hello due in 00:00:06
Index 1/1, flood queue length 0
Next 0x0(0)/0x0(0)
Last flood scan length is 1, maximum is 1
Last flood scan time is 0 msec, maximum is 0 msec
Neighbor Count is 2, Adjacent neighbor count is 2
Adjacent with neighbor 10.1.1.1 (Designated Router)
Adjacent with neighbor 10.1.1.2 (Backup Designated Router)
Suppress hello for 0 neighbor(s)
C# show ip ospf neighbor/span>
Neighbor ID Pri State Dead Time Address Interface
10.1.1.1 3 FULL/DR 00:00:35 10.1.1.1 FastEthernet0/0
10.1.1.2 1 FULL/BDR 00:00:37 10.1.1.2 FastEthernet0/0
Router1 is the DR with priority 3
still need more work to understand the output of the defbu ospf adj
Chapter 9 Review Questions
1. There are three possible routes for a router to reach a destination network:
OSPF with a metric of 782
RIPv2 with a metric of 4
EIGRP with a composite metric of 20514560
Which route will be installed in the routing table?
OSPF with a metric of 782
RIPv2 with a metric of 4
EIGRP with a composite metric of 20514560
Which route will be installed in the routing table?
EIGRP because it has the lowest Administrative Distance, and AD is always used before metric
ADs are:
ExternalEIGRP 170
RIP 120
OSPF 110
IGRP 100
EIGRP 90
Static 1
Connected 0
ADs are:
ExternalEIGRP 170
RIP 120
OSPF 110
IGRP 100
EIGRP 90
Static 1
Connected 0
2. Which EIGRP information is held in RAM and maintained through the use of Hello and update packets?
Neighbor table
and
toplogy table
and
toplogy table
3. Describe the process identifier that is used to run OSPF on a router
The OSPF process id is only locally significant. A random number can be selected. But it's required in order to identify
a unique OSPF database instance. You can use the same, or a different number on each router, doesnt matter.
Any number can be used from 1 to 65,535. Process ID is supplied as an argument to the command router ospf
NOT to be confused with the area number which can be any number up to 4 billion. The area id identifies a logical grouping of routers.
area id is supplied as argument to the OSPF network id and mask command
Ex:
R1(config)# router ospf 12345
R1(config-router)# net 10.1.1.0 0.0.0.255 area 0
Any number can be used from 1 to 65,535. Process ID is supplied as an argument to the command router ospf
NOT to be confused with the area number which can be any number up to 4 billion. The area id identifies a logical grouping of routers.
area id is supplied as argument to the OSPF network id and mask command
Ex:
R1(config)# router ospf 12345
R1(config-router)# net 10.1.1.0 0.0.0.255 area 0
4. Where are EIGRP successor routes stored?
EIGRP succesor routers are stored in the routing table. The "succesor" is the successful or primary route.
The successor route is ALSO listed in the topology table,
The feasible successor is a BACKUP route and will ONLY be listed in the topology table, unless the successor route fails,
in which case the feasible successor would become the successor
Note that my EIGRP setup doesnt seem to folow this.
CTRL-F jump to "remotely connected via remote ingress ip address"
the book states that EIGRP is automatically load-balancing our two links from R1 to corp.. is this why there is no feasible successor here?
I did some research and found that in our case, we are not using a Feasible Successor. You CAN have two Successors with equal metric, in which case EIGRP will automatically load-balance.
But I wanted to find out what a Feasible Successor actually looks like in the EIGRP topology table..
Kevin Wallace EIGRP article
Conclusion: EIGRP topology table wouldnt specifically say "Feasible Successor", but you would know by two routes appearing, one with a lower metric.
In my topology we have two equal-metric links and they are both considered "Successors". EIGRP uses them equally (load-balanced)
Corp# show ip eigrp toplogy
The successor route is ALSO listed in the topology table,
The feasible successor is a BACKUP route and will ONLY be listed in the topology table, unless the successor route fails,
in which case the feasible successor would become the successor
Note that my EIGRP setup doesnt seem to folow this.
CTRL-F jump to "remotely connected via remote ingress ip address"
the book states that EIGRP is automatically load-balancing our two links from R1 to corp.. is this why there is no feasible successor here?
I did some research and found that in our case, we are not using a Feasible Successor. You CAN have two Successors with equal metric, in which case EIGRP will automatically load-balance.
But I wanted to find out what a Feasible Successor actually looks like in the EIGRP topology table..
Kevin Wallace EIGRP article
Conclusion: EIGRP topology table wouldnt specifically say "Feasible Successor", but you would know by two routes appearing, one with a lower metric.
In my topology we have two equal-metric links and they are both considered "Successors". EIGRP uses them equally (load-balanced)
Corp# show ip eigrp toplogy
[cut]
P 172.16.10.0/24, 1 successors, FD is 28160
via 10.1.5.2 (28160/25600), FastEthernet0/0
P 192.168.10.0/24, 2 successors, FD is 2172416
via 10.1.3.2 (2172416/28160), Serial0/0/1
via 10.1.2.2 (2172416/28160), Serial0/0/0
P 192.168.20.0/24, 2 successors, FD is 2172416
via 10.1.3.2 (2172416/28160), Serial0/0/1
via 10.1.2.2 (2172416/28160), Serial0/0/0
P 192.168.30.0/24, 1 successors, FD is 2172416
via 10.1.4.2 (2172416/28160), Serial0/1/0
P 192.168.40.0/24, 1 successors, FD is 2172416
via 10.1.4.2 (2172416/28160), Serial0/1/0
5. Which command will display all the EIGRP feasible successor routes to a known router.
show ip eigrp topology
6. Find the configuration error. You type the following into your router, but dont see any routes in the routing table?
Router(config)# router ospf 1
Router(config-router)# network 10.0.0.0 255.0.0.0
Router(config)# router ospf 1
Router(config-router)# network 10.0.0.0 255.0.0.0
wrong wildcard mask
instead, could have used
0.255.255.255
or
0.0.0.255
the point is we need to specify the first octet as "allowed" into our OSPF config with a 0 mask.
The remaining bits are 'dont care' bits aka 'wildcard' aka 255
instead, could have used
0.255.255.255
or
0.0.0.255
the point is we need to specify the first octet as "allowed" into our OSPF config with a 0 mask.
The remaining bits are 'dont care' bits aka 'wildcard' aka 255
7. Which three protocols support VLSM, summarization, and discontigous networking?
RIPv2
EIGRP
OSPF
all 3 build and mainting routing tables, provide classless routing which allows VLSM, summarization, and discontigous networks
RIPv1 and IGRP build/maintain routing tables, but dont offer classless routing
EIGRP
OSPF
all 3 build and mainting routing tables, provide classless routing which allows VLSM, summarization, and discontigous networks
RIPv1 and IGRP build/maintain routing tables, but dont offer classless routing
8. Which are true regarding OSPF areas?
the 'backbone' is area 0
if using other areas, they all must directly connect to area 0
if using other areas, they all must directly connect to area 0
9. Which two network types have a designated router and a backup designated router?
Broadcast
NBMA- Non broadcast multi access. Ex: Frame Relay
network types that DO NOT use DR/BDR:
point to point
broadcast multipoint
NBMA- Non broadcast multi access. Ex: Frame Relay
network types that DO NOT use DR/BDR:
point to point
broadcast multipoint
10. You need to configure a router with a distance-vector protocol that allows classless routing. Which to use?
EIGRP is considered 'advanced distance vector' (ripv2 wasnt an option)
11. You need the IP address of the devices with which the router has established an adjacency.
Also, the retransmit interval and the queue counts for the adjacent routers need to be checked. What command will display the required information?
show ip eigrp neighbors
WRONG: show ip eigrp adjacency - there is no such command.. the word 'adjacency' is only used with debug ip OSPF adjacency
here are the possible commands for show ip eigrp and debug ip eigrp
show ip eigrp ?
WRONG: show ip eigrp adjacency - there is no such command.. the word 'adjacency' is only used with debug ip OSPF adjacency
here are the possible commands for show ip eigrp and debug ip eigrp
show ip eigrp ?
interfaces IP-EIGRP interfaces
neighbors IP-EIGRP neighbors
topology IP-EIGRP Topology Table
traffic IP-EIGRP Traffic Statistics
debug ip eigrp ?
summary IP-EIGRP summary route processing
12. You cant establish an adjacency relationship on a common ethernet link between two routers. Based on the output below, what is the cause of the problem?
RouterA#
Ethernet0/0 is up, line protocol is up
Internet Address 172.16.1.2/16, Area 0
Process ID 2, Router ID 172.126.1.2, Network Type BROADCAST, Cost: 10
Transmit Delay is 1 sec, State DR, Priority 1
Designated Router (ID) 172.16.1.2, interface address 172.16.1.1.
No backup designated router on this network
Timer intervals configured, Hello 5, Dead 20, Wait 20, Retransmit 5
Router B#
Internet Address 172.16.1.1/16, Area 0
Process ID 2, Router ID 172.126.1.1, Network Type BROADCAST, Cost: 10
Transmit Delay is 1 sec, State DR, Priority 1
Designated Router (ID) 172.16.1.1, interface address 172.16.1.2.
No backup designated router on this network
Timer intervals configured, Hello 10, Dead 40, Wait 40, Retransmit 5
mismatched timer intervals
OSPF default Hello is 10 and Dead is 40... RouterA was modified
13. Which is true regarding EIGRP successor routes?
Used in the routing table
also appears in the topolgy table
may (or may not) have a backup feasabile successor
also appears in the topolgy table
may (or may not) have a backup feasabile successor
14. Which type of OSPF network will elect a backup designated router?
broadcast multi-access
non-broadcast multiaccess
types of network that will NOT elect a BDR:
point to point and brodacast multipoint (hub/spoke topology)
non-broadcast multiaccess
types of network that will NOT elect a BDR:
point to point and brodacast multipoint (hub/spoke topology)
15. Which two commands will place network 10.2.3.0/24 into area 0?
Router(config)#
router ospf 10
Router(config-router)# network 10.2.3.0 0.0.0.255 area 0
Router(config-router)# network 10.2.3.0 0.0.0.255 area 0
16. With which network type will OSPF establish router adjacencies but not perform the DR/BDR election process?
Point to point
no election process occurs, there is never a DR on point to point
no election process occurs, there is never a DR on point to point
17. What are three reasons for creating OSPF in a heirarchical design?
decrease routing overhead
speed up convergence
confine stability to single areas of the network
speed up convergence
confine stability to single areas of the network
18. What is the administrative distance of OSPF?
110
19.
no auto summary
the network is considered discontigous because we have two classful network subnetted (on the left and right), seperated by a different classful address.
if auto summarization is taking place, the routers cant determine which side is which because both sides would be summarized as Class B, 172.16.0.0, which isnt specific enough to distinguish between the sides.
the network is considered discontigous because we have two classful network subnetted (on the left and right), seperated by a different classful address.
if auto summarization is taking place, the routers cant determine which side is which because both sides would be summarized as Class B, 172.16.0.0, which isnt specific enough to distinguish between the sides.
20. IF routers in a single area are configured with the same priority value, what value does a router use for the OSPF router ID in the absence of a loopback interface?
The highest IP of any PHSYICAL interface.
Trick question. Highest IP of any LOGICAL interface is an option. And is correct IF you had logical interfaces, but the question states that any "logical interfaces are absent".
At OSPF startup, the highest IP of *any* active interface on the router becomes the OSPF router ID. If you have loopback (logical) interfaces configured, one of them (the largest IP) will *override* the phsyical interfaces and the loopback IP becomes the RID.
Reference for which loopback (if multiple) wins:
packetpushers.net
Trick question. Highest IP of any LOGICAL interface is an option. And is correct IF you had logical interfaces, but the question states that any "logical interfaces are absent".
At OSPF startup, the highest IP of *any* active interface on the router becomes the OSPF router ID. If you have loopback (logical) interfaces configured, one of them (the largest IP) will *override* the phsyical interfaces and the loopback IP becomes the RID.
Reference for which loopback (if multiple) wins:
packetpushers.net
END CHAPTER 9
41 hours 2-14 thru 2-28-22
original total 184 hours
14 hours review 12-26 thru 12-28-22
review total hours 46
book page 502/822
184 + 46 = 230 hours * 60 = (13,800 min) / 500 pages =
avg 28 min/page (includes reading and exercises/labs + online research)
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