BGP fall over command

[davidxiayuan]

Hi Folks,

I am wondering when I implement BGP fall over command, Do I need to implement this command on both end of the routers to make the BGP session to be disconnected as soon as the link is down or as long as one end is implemented with that command. The BGP session will be disconnected on both end routers and routing to destination prefixes will be re-calculated?

Thank you

[paul driver]

Hello

If you can , However if you don’t have access to the other side of the peer I don’t think this will matter

If BFD initiates for whatever reason then the peer will be stripped down for both sides

Fyi --
BGP bfd fail over can be interface specific or enabled globally in the routing process ( meaning all interfaces)


res
Paul

[Masoud Pourshabanian · Accepted solution]

Hello,

If both sides are under your control, it should be configured on both sides. Suppose you have configured it only on one side. If the link between two peers goes down, peer with fall over takes the session down and caculates the best paths again if any other neighbor available, but other peer will wait until the dead time, then takes the session down.

"The BGP session will be disconnected on both end routers and routing to destination prefixes will be re-calculated"

BGP session will not be discoonect on both sides when only fall-over set on one side. It take the session down on one side, but if you have a link with a service provider, you care about your side, not about the service provider.

Masoud