Cannot connect two ospf-instances over tun-interface

[dawid k]

I'm trying to set up pretty simply configuration consisting of two linux
machines connected over tun-interface created by OpenVPN.

The VPN-connection is working fine - I can send data over this interface.
Now I installed bird and configured ospf on both devices. I can see that
both bird instances are sending hello packets on tun-interface however no
one of them is getting the message.

I can see with tcpdump, that every device is getting the hello-message.
However they are not forwarded to bird or bird just ignores them.

I tried my setup over cabel with eth0-interface and everything is working
fine. Right now every machine is advertising just one example static
network. I will focus on correct advertising later after I connect those
two instances.

The tun0 interface is working in type ptp and the netmask is
255.255.255.255. Do you have any idea what's wrong?

Thanks for every input, tookie009
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