Cannot connect two ospf-instances over tun-interface

[Ondrej Zajicek]

On Wed, Apr 04, 2018 at 11:35:03AM +0200, dawid k wrote:
> 2018-04-04 10:59 GMT+02:00 Jan Maria Matejka <jan.matejka at nic.cz>:
> 
> > Hello,
> >
> > please could you enable 'debug all' for the ospf protocol at server?
> > It should tell you whether it receives the packets and what is it doing
> > with them.
> >
> 
> It is enabled, Here the logs:
> 
> 
> no received packets, but with tcpdump on server I can see, that all devices
> are sending hello messages:

Hello

That is interesting, It is possible that there is some problem with
multicast on OpenVPN, as mentioned by Michael McConnell, but not in the sense
of multicast transmit (which works as seen by tcpdump), but multicast delivery
to userspace sockets (so BIRD does not get them).

One workaround would be to use NBMA interface type in BIRD OSPF. That
uses just unicast, so perhaps there would not be this problem. See 'type
nbma' OSPF option. Then you have to use 'neighbors' option to specify
client IPs on server and at least server IP (marked 'eligible') on clients
and set priority to 0 on clients.

-- 
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."