CLNS error: neighbor forgot us

[atif-siddiqui]

I have seen this strange error, ISIS flapped and was back up, but the best forwarding path was unable to forward packets it seems, router not reachable via telnet/ssh , can ping the interface, but traffic was being black holed. BGP , LDP session went down while ISIS was up.

someone have seen this ' CLNS error' neighbor forgot us.

FIX: shut / no shut the interface.

Mar 6 02:05:39.261 EST: %CLNS-5-ADJCHANGE: ISIS (prj): Adjacency to router5W (GigabitEthernet5/1) Down, neighbor forgot us

Mar 6 02:05:39.281 EST: %CLNS-5-ADJCHANGE: ISIS (prj): Adjacency to router5W (GigabitEthernet5/1) Up, new adjacency

Mar 6 02:07:00.989 EST: %LDP-5-NBRCHG: LDP Neighbor x.x.x.129:0 (3) is DOWN (Discovery Hello Hold Timer expired)

Mar 6 02:07:45.134 EST: %BGP-5-ADJCHANGE: neighbor x.x.x.31 Down BGP Notification sent

Mar 6 02:07:45.134 EST: %BGP-3-NOTIFICATION: sent to neighbor x.x.x.31 4/0 (hold time expired) 0 bytes

Mar 6 02:08:06.882 EST: %LDP-5-NBRCHG: LDP Neighbor x.x.x.181:0 (1) is DOWN (Session KeepAlive Timer expired)

Mar 6 02:09:29.262 EST: %CLNS-5-ADJCHANGE: ISIS (prj): Adjacency to router5W (GigabitEthernet5/1) Down, neighbor forgot us

Mar 6 02:09:29.282 EST: %CLNS-5-ADJCHANGE: ISIS (prj): Adjacency to router5W (GigabitEthernet5/1) Up, new adjacency

Cisco 7606:

Cisco IOS Software, c7600s3223_rp Software (c7600s3223_rp-ADVIPSERVICESK9-M), Version 12.2(33)SRB2, RELEASE SOFTWARE (fc1)

[bwilmoth]

"Neighbor forgot us" could mean, that the dead timer on the other side fired and the other side sends a new init

[ana.peric]

I had the similar problem with 12.2(33)SRB3 IOS.

In my case isis routing was up after shut / no shut of physical interface, and what is even more strange, isis process on router that was 5 to 8 hops away from 7600 was up too after interface reset.

atif-siddiqui, did you find an answer to this issue???

Best Regards,

Ana