Cisco Support Community
cancel
Showing results for 
Search instead for 
Did you mean: 
Announcements

Welcome to Cisco Support Community. We would love to have your feedback.

For an introduction to the new site, click here. And see here for current known issues.

Bronze

Eigrp flapping

Hi,

We are using eigrp and have problems with routing protocol flapping:

*Sep 6 16:15:36.379 CEST: %DUAL-5-NBRCHANGE: IP-EIGRP(0) 1: Neighbor 172.16.0.1 (Tunnel1) is up: new adjacency

*Sep 6 16:16:20.079 CEST: %DUAL-5-NBRCHANGE: IP-EIGRP(0) 1: Neighbor 172.16.0.1 (Tunnel1) is down: holding time expired

*Sep 6 16:16:29.483 CEST: %DUAL-5-NBRCHANGE: IP-EIGRP(0) 1: Neighbor 172.16.0.1 (Tunnel1) is up: new adjacency

*Sep 6 16:17:07.547 CEST: %DUAL-5-NBRCHANGE: IP-EIGRP(0) 1: Neighbor 172.16.0.1 (Tunnel1) is down: holding time expired

*Sep 6 16:17:19.631 CEST: %DUAL-5-NBRCHANGE: IP-EIGRP(0) 1: Neighbor 172.16.0.1 (Tunnel1) is up: new adjacency

*Sep 6 16:17:57.871 CEST: %DUAL-5-NBRCHANGE: IP-EIGRP(0) 1: Neighbor 172.16.0.1 (Tunnel1) is down: holding time expired

*Sep 6 16:18:05.723 CEST: %DUAL-5-NBRCHANGE: IP-EIGRP(0) 1: Neighbor 172.16.0.1 (Tunnel1) is up: new adjacency

*Sep 6 16:18:50.675 CEST: %DUAL-5-NBRCHANGE: IP-EIGRP(0) 1: N

Any ideas ?

BR,

Bjornarsb

4 REPLIES
New Member

Re: Eigrp flapping

Hi,

Eigrp neighborship can flap due to several reasons. just enable debugging in the router and try to find out the reason. Copy and send the debug logs.

Thanks

Mahi

Hall of Fame Super Silver

Re: Eigrp flapping

Bjornarsb

The messages indicate that it is over interface tunnel1 from which I assume that this is at least a GRE tunnel and perhaps GRE with IPSec running EIGRP. I have implemented this functionality for a customer (with the tunnel running through the Internet) and we experienced the symptoms of EIGRP flapping like this. We found that if we increased the EIGRP timers for hello-interval and for hold-time on the tunnel interfaces that the symptoms improved. We still experience some neighbor instability but it is much less than it was with the default timers. You might try increasing the EIGRP timers and let us know if it makes any difference in your environment.

HTH

Rick

Bronze

Re: Eigrp flapping

Hi,

I've already tried to do this according to the doc.

It does not help:

!

interface Tunnel1

bandwidth 384

ip address 172.16.0.32 255.255.0.0

no ip redirects

ip mtu 1400

ip hello-interval eigrp 1 60

ip hold-time eigrp 1 180

BR,

Bjornarsb

Bronze

Re: Eigrp flapping

It says holdtime expired, but I cannot find the reason why ?

See attachment.

601
Views
0
Helpful
4
Replies