[Babel-users] MTU based routing for tunnel based babel networks?

[Daniel Gröber]

On Thu, Jul 20, 2023 at 02:40:40PM +0200, Daniel Gröber wrote:
> On Wed, Jul 19, 2023 at 11:25:52PM +0200, Juliusz Chroboczek wrote:
> > Could you please test the new branch "probe-mtu"?  It's now using the
> > IPV6_DONTFRAG cmsg in sendmsg, so it's enough to say
> > 
> >     default probe-mtu true
> > 
> > (No global options, only per-interface options.)
> 
> I can observe (some) hellos using the padding depending on the option
> setting. Problem is when I force the interface MTU to 1280 instead of the
> initial 1420 the padded hellos get dropped and don't reach the other side
> as you'd expect, but the regular sized hellos still make it through and so
> the neighbourship relationship stays up.

Uups, nevermind this. I was looking at the other node's hellos. The
neighbour relationship goes down properly as you'd expect.

--Daniel