LAB 2-3: CDP NEIGHBORS COMMAND
S0/0 R2
DCE
S0/1
R1
¾
M a c intos h SE
Objective: Understanding of the CDP NEIGHBORS command.
The show cdp neighbors command allow you to get a snapshot view of the
routers that are directly connected to your routers and can be used to build
a logical diagram of the network.
Connect to your router via the console port as shown in the above diagram subnetting the
network address 200.2.2.0/24 and 194.1.1.0/24.
Step 1 - Enter user mode with cisco password (from router console or telnet session)
Step 2 - Gather information about the router you are logged into by issuing
the show run command.
Document in your LAB Engineering Journal the following information
about your router.
Router hostname: _________________________________________________
Type of network interfaces(S0,E1, etc.): _______________________________
IP address and Subnet Masks for all the interfaces. Place the information below
if applicable:
S0: ________________________________________________________
S1: ________________________________________________________
E0: ________________________________________________________
E1: ________________________________________________________
Operational status of each interface from above ( administrative, protocol, up or
down):
Step 3 - From Router R1, do the following commands: enter the show cdp neighbors
command.
Document in you LAB Engineering Journal the information this command
has given you about your neighbors.
Enter show cdp neighbors detail command.
Document in your LAB Engineering Journal any additional information this
command has given you about your neighbors.
Example of information to gather for all the neighbors of the router:
(Note: “Interface: S0/0” is the interface of the router that you are on that
connects to the neighbor.
“Port ID (Outgoing port)” is the interface on the ‘neighbor’ router that is
connected to the above Interface: S0/0) When in doubt check the topology on
a lab exercise.)
1) Neighbor Device Name1a) Neighbor Device Type2) Type and IP address of Neighbor Interface attached to your router 3) Port ID on your router that the neighbor is on4) Port ID of Neighbor Interface that is attached to your router5) IOS version of software that is running on your Neighbor routerDevice ID
Platform
Interface
Outgoing Port
IOS ver.
Step 4 – Do a ‘telnet <device ID>’ (where device ID is IP address on the router you
found from above) for each device ID you found in step 3. (Note, telnet allows you to ‘log
into your neighbor’s router’. Notice the prompt!)
Remember the login and password MUST be configure on the VTY interfaces!
Step 5 – When you telnet into each device id, do a show cdp neighbor detail. Record
this information for each:
Device ID
Platform
Interface
Outgoing Port
IOS ver.
Step 5 - From the information gathered in steps 3 and 5 develop a logical diagram
of the network and document this in your LAB Engineering Journal. That is, label
each router’s hostname, router’s interfaces, router’s interfaces IP addresses and
how is each router is connected to each other. So you will have a logical diagram
of WAN.