BFD+BGP behavior difference between bird 1.6 and 2.0
Hello! After upgrading to 2.0 I have noticed that "bgp on" in BGP peer configuration creates a separate BFD session, however it wasn't like that in bird 1.6, we had to specify neighbors in BFD section. Now for bird 2.0 it looks like specifying neighbors in BFD section is not necessary when "bgp on" is set in BGP configuration. The problem I have faced was "unknown session id" errors between two BGP routers, one running bird 1.6 and another running bird 2.0, same config. It looked like bird 2.0 was creating two BFD sessions comparing to bird 1.6 that created only one. Removing neighbor from BFD section at bird 2.0 fixed the issue. Can anybody tell me if anything has changed in 2.0 or am I missing something? The documentation looks quite similar for both versions in this case.
On Thu, Oct 28, 2021 at 02:31:56PM +0300, Kseniya Blashchuk wrote:
Hello! After upgrading to 2.0 I have noticed that "bgp on" in BGP peer configuration creates a separate BFD session, however it wasn't like that in bird 1.6, we had to specify neighbors in BFD section. Now for bird 2.0 it looks like specifying neighbors in BFD section is not necessary when "bgp on" is set in BGP configuration.
Hello I don't know anything about "bgp on" option. Do you mean "bfd on" option in BGP config? I do not think this changed between 1.6 and 2.0, even in BIRD 1.6 there should not be necessary to use BFD neighbor config option if you use BFD with BGP or OSPF, this option (BFD neighbor) is here primarily for independent/unrelated BFD sessions. -- Elen sila lumenn' omentielvo Ondrej 'Santiago' Zajicek (email: santiago@crfreenet.org) OpenPGP encrypted e-mails preferred (KeyID 0x11DEADC3, wwwkeys.pgp.net) "To err is human -- to blame it on a computer is even more so."
Hello! I am sorry, yes I sure meant "bfd on" in BGP config. However, the same configuration between 1.6 and 2.0 gives me "unknown session id" errors and double sessions at bird 2.0. I will check maybe if bird 1.6 really needs neighbors in bfd configuration for BGP, just for interest.
participants (2)
-
Kseniya Blashchuk -
Ondrej Zajicek