Bird bfd configuration

[Ondrej Zajicek]

On Mon, Feb 13, 2023 at 02:56:56PM +0000, LIU Chris wrote:
> Hi Zajicek,
> 
> Many thanks for your reply.
> No any problem to set just one BFD instance.  In my case, I have multiple BGP instances,  I set bfd on inside each BGP instance.
> If just one bfd instance,  how do bird correlate with BGP instances ? 

The BFD instance knows which BGP instance requested that peer, so it
notified appropriate BGP instance if something happens with that peer.

> And also, if want to set different min/max Rx interval value for each BGP session in BFD instance configuration, how to distinguish them ?

If they are on different ifaces (like in your example), you can have multiple interface statements in one BFD instance.

But in general, you can specify BFD parameters also directly in BGP protocol as options of 'bfd' switch:

https://bird.network.cz/?get_doc&v=20&f=bird-6.html#bgp-bfd

protocol bfd {
}

protocol bgp {
  ...
  bfd {
    min rx interval 1000000 us;
    min tx interval 1000000 us;
  };
}


-- 
Elen sila lumenn' omentielvo

Ondrej 'Santiago' Zajicek (email: santiago at crfreenet.org)
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"To err is human -- to blame it on a computer is even more so."