Arista Switch BFD issue - custom port

[Ondrej Zajicek]

On Mon, Aug 13, 2018 at 03:14:10PM +0200, Jakub Nowacki wrote:
> Hi,
> 
> I'm running BIRD on Arista which allows access to Linux bash. I'm having
> issue with running multihop BFD session on it and I believe it's related to
> port being already binded.
> 
> > bash-4.3# netstat -tulpen | grep 4784
> >
>  udp6       0      0 :::4784                 :::*
> >       0          4269       -

Hi

I thing 4269 here is PID, what is the process? netcat should return the
process name, which is not here, but perhaps it is some limited variant
of netcat. Maybe BFD is implemented in control plane on Arista, so it
collides on kernel level?

Also, there should be an error message in the BIRD log related to bind
errors.

> I couldn't find any configuration option for BFD to change port being used,
> but maybe there is one?

There is no such option. Perhaps we should add it, as BGP and RIP also
have port option.

> Perhaps anyone run into similar issue and have a workaround?

As a workaround you can recompile BIRD with changed BFD_MULTI_CTL_PORT in
proto/bfd/bfd.h file.

-- 
Elen sila lumenn' omentielvo

Ondrej 'Santiago' Zajicek (email: santiago at 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."