BFD on back-to-back connected BGP-speakers

Ryan L ryan.nsplist at
Tue Nov 29 19:13:13 UTC 2016

Hugo, I think those are all valid potential reasons to use BFD. I use it
for some of the same reasons even on direct connect peers.

Only time I ever recall actively avoiding it if I had the capability was if
I had NSF/SSO, since they didn't used to (still don't?) play very well

On Tue, Nov 29, 2016 at 1:23 PM, Hugo Slabbert <hugo at> wrote:

> Good morning, nanog,
> Is there any/sufficient benefit in adding BFD onto BGP sessions between
> directly-connected routers?  If we have intermediate L2 devices such that
> we can't reliably detect link failures BFD can help us quickly detect peers
> going away even when link remains up, but what about sessions with:
> - eBGP with peering to interface addresses (not loopback)
> - no multi-hop
> - direct back-to-back connections (no intermediate devices except patch
>  panels)
> Possible failure scenarios where I could see this helping would be fat
> fingering (filters implemented on one or the other side drops traffic from
> the peer) or e.g. something catastrophic that causes the control plane to
> go away without any last gasp to the peer.
> Or is adding BFD into the mix in this type of setup getting into
> increasing effort/complexity (an additional protocol) for dimishing returns?
> --
> Hugo Slabbert       | email, xmpp/jabber: hugo at
> pgp key: B178313E   | also on Signal

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