Nexus-7000 and Cisco 6500 EIGRP neighboor issue

[mohan mayilraj]

Hi,

We are trying to connect Nexus-7k to our Environment Cisco 6500. we are having issue forming EIGRP relation between switches and getting error like below.

2012 Jul  8 21:22:44.359 E2-N7K-01 %EIGRP-5-NBRCHANGE_DUAL:  eigrp-30 [6949] (de

fault-base) IP-EIGRP(0) 30: Neighbor 172.16.x.x (Vlanxxx) is down: Interface G

oodbye received.

verified both K values are same in the switches (default)s.

please let us know how to fix this issue

[Peter Paluch]

Hello Mohan,

It's a totally blind shot but try to verify the EIGRP Router IDs (they are displayed in the show ip eigrp topology output like "EIGRP-IPv4 Topology Table for AS(1)/ID(10.0.0.1)" ). It is theoretically possible that these two EIGRP speakers happen to have the same RouterID. Although in my experience, an identical EIGRP RID has not caused the EIGRP adjacency to flap or to emit Goodbye messages, I nevertheless suggest checking it.

Also make sure that the K-values are not all set to 255 - that is precisely the Goodbye message your Nexus is complaining about. By the way, is there any logging message recorded on the 6500?

Best regards,

Peter

[mikegrous]

Are  you peering over a VPC VLAN? IF so that is your issue.

http://bradhedlund.com/2010/12/16/routing-over-nexus-7000-vpc-peer-link-yes-and-no/

[sbhadrav@cisco.com]

ip prefix-list <NAME> deny 172.31.240.0/24
ip prefix-list <NAME> permit 0.0.0.0/0 le 32

int <x/y> <--- this connects to 6500
ip distribute-list eigrp Center prefix-list <NAME> in

where <NAME> is whatever you want.
You can use a distribute list.
Couple of points -
1) If the 6500 and Nexus are connected via a P2P link then you could configure the distribute list outbound on the 6500 to stop it sending certain routes to the Nexus switch or inbound on the Nexus switch to stop it receiving them.
Either would work.
If however the 6500 and Nexus are on a common vlan where the 6500 peers with other EIGRP neighbors then you should apply it inbound on the Nexus because the 6500 would still need to send those routes to it's other neighbors.

2) if you want to filter the majority of routes then you should write your acl or prefix list to only permit the specific routes you want.

If you want to accept the majority of routes then you should write your acl or prefix list to deny the routes you don't want and then accept the rest.

So you need to know which of the above it is.