show cdp neighbor doesn't show up any neighbor

[tranminhc]

Hi,

I have one router C3925 which uses HWIC-4ESW module card to connect to two Gigabit port on 2960 SWs. The Router can ping two SWs, but no neighbor when issue "show cdp" command. However, 2 SW can see the router in "show cdp neighbor" command.

The Router has IOS "c3900-universalk9-mz.SPA.151-4.M2.bin" installed on it.

All connected ports are trunk.

Thanks to any advices

[Rasika Nayanajith]

Does "sh cdp interface" output of your 3900 router show the HWIC interfaces as CDP enable ?

Rasika

[Junaid Shah]

Can you please share the configuration of trunk ports at both end. Thanks

[Mohammed Yaseen Ansari]

Hello, Can you check if 'no cdp enable' command applied on trunk interfaces of the router.

Regards,

Yaseen

[tranminhc]

Hi,

This is my configuration file

On Router

interface FastEthernet0/0/0

description " TO RP-Router-2 "

switchport mode trunk

no ip address

!

interface FastEthernet0/0/1

description " TO RP-Sw-1 "

switchport mode trunk

no ip address

!

interface FastEthernet0/0/2

description " TO RP-Sw-2 "

switchport mode trunk

no ip address

!

interface FastEthernet0/0/3

no ip address

!

On Switch

interface GigabitEthernet0/1

description " TO RP-Router-1 "

switchport mode trunk

switchport nonegotiate

!

interface GigabitEthernet0/2

description " TO RP-Router-2 "

switchport mode trunk

switchport nonegotiate

!

on my Router, CDP is enabled by default

RP-Router-1#show cdp interface

Embedded-Service-Engine0/0 is administratively down, line protocol is down

  Encapsulation ARPA

  Sending CDP packets every 60 seconds

  Holdtime is 180 seconds

GigabitEthernet0/0 is administratively down, line protocol is down

  Encapsulation ARPA

  Sending CDP packets every 60 seconds

  Holdtime is 180 seconds

GigabitEthernet0/1 is up, line protocol is up

  Encapsulation ARPA

  Sending CDP packets every 60 seconds

  Holdtime is 180 seconds

GigabitEthernet0/2 is up, line protocol is up

  Encapsulation ARPA

  Sending CDP packets every 60 seconds

  Holdtime is 180 seconds

FastEthernet0/0/0 is up, line protocol is up

  Encapsulation ARPA

  Sending CDP packets every 60 seconds

  Holdtime is 180 seconds

FastEthernet0/0/1 is up, line protocol is up

  Encapsulation ARPA

  Sending CDP packets every 60 seconds

  Holdtime is 180 seconds

FastEthernet0/0/2 is up, line protocol is up

  Encapsulation ARPA

  Sending CDP packets every 60 seconds

  Holdtime is 180 seconds

FastEthernet0/0/3 is down, line protocol is down

  Encapsulation ARPA

  Sending CDP packets every 60 seconds

  Holdtime is 180 seconds