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Interface flap / Peer closed the session, BGP problem.

From the following error log.Could you have some suggestion for me please?What is the cuase of this error?

Thank you for your help.

saman chaiyuchit

Jan15.msg.log:Jan 15 10:49:32 6018: Jan 15 10:33:33: %BGP-5-ADJCHANGE: neighbor Down - Interface flap

Jan15.msg.log:Jan 15 10:50:17 6025: Jan 15 10:34:19: %BGP-5-ADJCHANGE: neighbor Up

Jan23.log:Jan 23 17:08:51 6335: Jan 23 16:50:24: %BGP-5-ADJCHANGE: neighbor Up

Jan3.log:Jan 3 04:13:04 47826: Jan 3 04:00:45: %BGP-5-ADJCHANGE: neighbor Down - Peer closed the session

Jan3.log:Jan 3 04:49:06 110: Jan 3 04:36:47: %BGP-5-ADJCHANGE: neighbor Up


Re: Interface flap / Peer closed the session, BGP problem.

Hi, here are some info from the Error decoder tool:

"A BGP neighbor has either come up or gone down. The message describes the change that has occurred. This message appears only if the log-neighbor-changes command is configured for the BGP process.

Recommended Action: This informational message normally appears as routers and BGP neighbors go up or down. However, unexpected neighbor loss might indicate high error rates or high packet loss in the network and should be investigated."

From the logs that you have posted, it happened on Jan. 3, Jan 15, and Jan 23. If you are not making some configuration changes on those days, probably the remote end does.

(But that may not be the only reason for the interface flap)

Hope this helps.

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