Re: " bfd1: Socket error: Destination address required"

[Fran via Bird-users]

Hello Alexander,

thanks for your email.
I started without any neighbor config in the BFD section and the error 
message was there, while trying to get rid of the error I first added 
the "local <IP address>"  and then the "dev <interface>" options. The 
error message appears non the less.

Best,

fran



On 29/04/2024 17:20, Alexander Zubkov wrote:
Hi,

You do not need to define neighbors for BGP sessions explicitly in
your BFD config. They are created automatically for BGP sessions with
BFD enabled. In that case, I suppose, you won't get errors for the
missing neighbors.

Regards,
Alexander

On Mon, Apr 29, 2024 at 1:16 PM Fran via Bird-users
<bird-users@network.cz> wrote:

Hello there,

I get the error message:

"<ERR> bfd1: Socket error: Destination address required"

(ubuntu 22.04, bird via ppa 2.15.1) running BFD and MP-BGP via IPv6 over
wireguard interfaces. Not all BGP neighbors are reachable.

Relevant (I hope) config:

log "/var/log/bird/bird.log" all;

protocol device {
}

protocol bfd {
    accept ipv6 direct;
    interface "wg_blue*";
    interface "wg_green" {
      multiplier 3;
      interval 500 ms;
    };
    neighbor 2001:db8:f000::2 dev "wg_green" local 2001:db8:f000::1;
    neighbor 2001:db8:f000:ffff::2 dev "wg_blue2" local
2001:db8:f000:ffff::1;
    neighbor 2001:db8:f000:fffc::5 dev "wg_blue1" local
2001:db8:f000:fffc::1;
    neighbor 2001:db8:f000:fffc::4 dev "wg_blue1" local
2001:db8:f000:fffc::1;
    neighbor 2001:db8:f000:fffc::3 dev "wg_blue1" local
2001:db8:f000:fffc::1;
    neighbor 2001:db8:f000:fffc::2 dev "wg_blue1" local
2001:db8:f000:fffc::1;
}


protocol bgp EXAMPLE {
    local as 65001;
    neighbor 2001:db8:f000::2 as 65044;
    direct;
    med metric yes;
    ipv4 {
      ...
    };
    ipv6 {
      ...
    };
    bfd on;
}


If I remove the BFD config for the non-established BGP neighbors, the
error message disappears (although there are still non-established BFD
sessions for established BGP neighbors (BFD not yet confed on the other
end)).

At first I did not create neighbor statements for BFD, then I added
"dev" and "local" options - no improvement.

No revelations with "debug protocols all".

Any ideas? Thanks a lot!

Best,

fran