Eigrp nei bounce between MAN connection.

[mahesh18]

Hi all,

We have MAN conenction between two sites.

one site went down for 20 mins.

Here is logs

Apr 20 15:25:53 CST: %DUAL-5-NBRCHANGE: IP-EIGRP 22: Neighbor 10.17.62.5 (Vlan62) is down: holding time expired

Apr 20 15:25:54 CST: %DUAL-5-NBRCHANGE: IP-EIGRP 22: Neighbor 10.17.62.6 (Vlan62) is down: holding time expired

Apr 20 15:42:25 CST: %DUAL-5-NBRCHANGE: IP-EIGRP 22: Neighbor 10.17.62.6 (Vlan62) is up: new adjacency

Apr 20 15:42:25 CST: %DUAL-5-NBRCHANGE: IP-EIGRP 22: Neighbor 10.17.62.5 (Vlan62) is up: new adjacency

Does anyone can tell reason for eigrp nei bounce.

thanks

mahesh

[Richard Burts]

Mahesh

The first two log messages indicate that the holding time expired. The EIGRP holding time is generally 3 times the EIGRP hello interval. Can you tell us whether any of the routers involved have changed either the EIGRP hello timer or the EIGRP hold timer?

In general what this error indicates is that for some reason the router which generates the error message has missed 3 consecutive hello messages from the neighbor(s). If the router misses at least 3 consecutive hello messages it generally indicates that there is a problem with the neighbor or a problem with the media over which the neighbors are connected.

You describe this as a MAN connection between 2 sites for which I would generally expect 1 neighbor. But I am curious that this router has 2 neighbors on this interface. Can you clarify the topology?

In looking at the time stamps it appears to be about 16 and a half minutes from the time that the neighbors failed to the time that the neighbors came back. If you look on the neighbor routers do they indicate interruptions in service at about the same time?

My guess is that the MAN connection was having problems for those 16 and a half minutes.

HTH

Rick

[mahesh18]

Hi Rick,

thanks for reply.

Here is other end on Man conenction

on that router there are no logs

i check this

sh ip eigrp nei

IP-EIGRP neighbors for process 22

H Address Interface Hold Uptime SRTT RTO Q Seq Type

(sec) (ms) Cnt Num

7 10.12.5.4 Vl426 10 00:00:32 1 5000 47 7808499

21 10.17.62.1 Vl58 14 22:25:39 11 200 0 1138674

8 10.17.62.3 Vl58 14 22:25:41 10 200 0 1135040

20 10.12.5.1 Vl426 14 1w4d 7 200 0 4608961

10.17.62.1 and .3 these nei were refreshed.

Let me know if you need any other info

thanks

mahesh

[mahesh18]

Hi rick,

also we speak to telco they told us they had no issues.there router is clean.

As this is Man so it is just layer1.

Router at both ends have no ligs that shows if any interface bounce.

[Richard Burts]

mahesh

If the other routers do not have logs to show what happened and if the telco says that they had no issues, then it will be difficult to determine what happened. All I can say at this point is that the original post has log messages that show that for about 16 and a half minutes the router was not receiving EIGRP hello messages.

HTH

Rick