EIGRP Retry Limit Issue

[mrashby]

All,

I have a L3 connection between one of my core switches and a router. Ever since that connection was made I get this error in my logs:

Sep 17 09:41:25.804 EDT: %DUAL-5-NBRCHANGE: IP-EIGRP(0) 1: Neighbor 16.11.17.218 (GigabitEthernet3/1) is up: new adjacency

Sep 17 09:42:45.315 EDT: %DUAL-5-NBRCHANGE: IP-EIGRP(0) 1: Neighbor 16.11.17.218 (GigabitEthernet3/1) is down: retry limit exceeded

The only thing I noticed is that I can ping the router interface from the Core switch but I can't ping the core switch from the router. I have checked the interfaces and everything is identical so everything seems to be cool. I can't really see what the issue is unless there is something else going on I am missing. Any help would be appreciated.

[Richard Burts]

Mario

It sounds like you have one way traffic. One thing I would do to check this is to look on the switch and see whether you see the router as a CDP neighbor. If CDP is enabled and if the switch sees the router as a neighbor then it indicates that you have layer 2 connectivity and that there may be some layer 3 problem (possibly misconfigured address, misconfigured mask, access list, or something). If CDP is enabled and if the switch does not see the router as a neighbor then it indicates that there is some problem at layer 1 or layer 2 which is preventing traffic from the router to the switch.

HTH

Rick