BGP Hold timer expired error means?

[palani2010]

BGP Hold timer expired error means?

The EBGP scenerio between our company and the vendor end was constantly flapping, which was caused by a BGP hold timer expired error as shown in the logging.

[Flavio Miranda]

"In normal scenarios, when a Border Gateway Protocol (BGP) peer goes down, a router only waits for the hold timer to expire to declare the neighborship as down (90 seconds default). But in some cases, a router will retain this dead adjacency up for a longer time even if the BGP timers have expired"

[MHM Cisco World]

BGP keep alive is misconfig.

check this point
https://www.cisco.com/c/en/us/td/docs/routers/xr12000/software/xr12k_r4-1/routing/configuration/guide/routing_cg41xr12k_chapter1.html

[Harold Ritter · Accepted solution]

Hi @palani2010 ,

This type of flapping generally denotes a path MTU issue between the BGP peers.

Please refer to the following document on how to troubleshoot this issue:

https://www.cisco.com/c/en/us/support/docs/ip/border-gateway-protocol-bgp/116377-troubleshoot-bgp-mtu.html

Regards,