Solved: EIGRP neighbor drops over GRE tunnel

rluyster · ‎12-17-2008

I have several users working from home with an 871 router connecting to a 2811 in our main office. While most of these connections work without any issues, I have a few sites which continue to drop the EIGRP neighbor. Here is a sample of the log file

*Dec 17 06:32:48: %DUAL-5-NBRCHANGE: IP-EIGRP(0) 10: Neighbor 172.29.1.49 (Tunnel1) is up: new adjacency

*Dec 17 06:41:58: %DUAL-5-NBRCHANGE: IP-EIGRP(0) 10: Neighbor 172.29.1.49 (Tunnel1) is down: Interface Goodbye received

*Dec 17 06:42:03: %DUAL-5-NBRCHANGE: IP-EIGRP(0) 10: Neighbor 172.29.1.49 (Tunnel1) is up: new adjacency

*Dec 17 06:43:41: %DUAL-5-NBRCHANGE: IP-EIGRP(0) 10: Neighbor 172.29.1.49 (Tunnel1) is down: Interface Goodbye received

*Dec 17 06:43:46: %DUAL-5-NBRCHANGE: IP-EIGRP(0) 10: Neighbor 172.29.1.49 (Tunnel1) is up: new adjacency

*Dec 17 06:49:30: %DUAL-5-NBRCHANGE: IP-EIGRP(0) 10: Neighbor 172.29.1.49 (Tunnel1) is down: Interface Goodbye received

*Dec 17 06:49:33: %DUAL-5-NBRCHANGE: IP-EIGRP(0) 10: Neighbor 172.29.1.49 (Tunnel1) is up: new adjacency

Does anyone have any thoughts as to what may be causing this issue?

Richard Burts · ‎12-18-2008

Rick

We run EIGRP over GRE/IPSec tunnels to lots of remote routers. We have seen this EIGRP neighbor instability issue, more at some locations and less at others. Frequently one side drops the neighbor relationship and sends a "goodby" to the neighbor. I assume that it has to do with packet loss dropping some of the EIGRP hello messages. We found that by increasing the EIGRP timers we reduced the frequency with which we see the problem (we are using 15 and 45 rather than the default 5 and 15).

HTH

Rick

HTH

Rick

View solution in original post

ajagadee · ‎12-17-2008

Hi,

The message "Interface Goodbye received" is due to graceful shutdown documented in CSCdr96531. The

interface goodbye is sent from the peer proactively when it takes down peers on an interface. For interface goodbye (we also have peer goodbye) it's signalled via a hello with the k-values set as invalid. On

receipt we can down the peer locally without delay.

I would suggest that you do the regular troubleshooting between the 871 and 2811 to find out why the peer clears in the first place.

Regards,

Arul

*Pls rate if it helps*

Richard Burts · ‎12-18-2008

Rick

We run EIGRP over GRE/IPSec tunnels to lots of remote routers. We have seen this EIGRP neighbor instability issue, more at some locations and less at others. Frequently one side drops the neighbor relationship and sends a "goodby" to the neighbor. I assume that it has to do with packet loss dropping some of the EIGRP hello messages. We found that by increasing the EIGRP timers we reduced the frequency with which we see the problem (we are using 15 and 45 rather than the default 5 and 15).

HTH

Rick

HTH

Rick

Richard Burts · ‎12-19-2008

Rick

I am glad that my response was helpful. Thank you for using the rating system to indicate that your issue was resolved (and thanks for the rating). It makes the forum more useful when people can read about an issue and can know that they will read responses that lead to a resolution of the issue.

The forum is an excellent place to learn about Cisco networking. I encourage you to continue your participation in the forum.

HTH

Rick

HTH

Rick