bfd adjacency

[petercinvest]

I check the  router A, it says bfd adjacency down, bgp session down, but when i use show int G1/0/3 (this interface is bgp neighbor connected), it doesn't show when this interface is down, is there any other command can show that when interface is down (except viewing the log)

what are other  root cause of bfd session  down besides interface is down

[paul driver]

Hello

BFD uses its own control packets to monitor a peering link(s), irrespective of bgp timer your have set in the routing stanza

For a bgp peering to be torn down means that the BFD neighborship was lost, and as such BFD notified bgp to tear down the peering.

Such action would indicate the communication between the bgp peers was lost for such time period that warranted bfd to take the action it did.

It could also be your bfd intervals set to low.

res
Paul

res
Paul

[Joseph W. Doherty]

what are other  root cause of bfd session  down besides interface is down

BFD packets are not seen on the other side.

Of course if interface is down, BFD packets will not be seen, but if BFD packets are lost, for any reason (e.g. congestion or corruption), same result.

[SOHAN HEGDE]

Hii,

Normally Gig interface remain up even when CCT is down. you have any IP SLA configured to track the interface.