I have some issues runinng a few Bird-instances, where two border PC's are connected over a VPN-Connection. The image below shows the setting:

clientA 192.168.30.2 (eth) | | 192.168.30.1 (eth) routerA 192.168.21.5 (eth) | | 192.168.21.1 (eth) clientB 10.29.0.8 (tun) | | 10.29.0.1 (tun) Server 10.29.0.1 (tun) | | 10.29.0.4 (tun) clientC 192.168.21.17 (eth)

Now running route -n on ClientC gives following result:

route -n (routes with metric 12 are set by bird) Destination Gateway Genmask Flags Metric Ref Use Iface 10.29.0.0 0.0.0.0 255.255.252.0 U 0 0 0 tun0 WWWWW 0.0.0.0 255.255.255.252 U 0 0 0 eth1 XXXXXXX 0.0.0.0 255.255.255.255 UH 1024 0 0 eth1 192.168.21.0 10.29.0.8 255.255.255.240 UG 12 0 0 tun0 192.168.21.16 0.0.0.0 255.255.255.240 U 0 0 0 eth0 192.168.30.0 10.29.0.8 255.255.255.240 UG 12 0 0 tun0 On Server: Ziel Router Genmask Flags Metric Ref Use Iface 192.168.21.16 10.29.0.4 255.255.255.240 UG 17 0 0 tun0 192.168.21.0 10.29.0.8 255.255.255.240 UG 17 0 0 tun0 192.168.30.0 10.29.0.8 255.255.255.240 UG 17 0 0 tun0 192.168.20.0 0.0.0.0 255.255.255.0 U 0 0 0 eth0 10.29.0.0 0.0.0.0 255.255.252.0 U 0 0 0 tun0 ZZZZZZZZ 0.0.0.0 255.255.0.0 U 1002 0 0 eth0

With 

birdc show ospf neighbors

I can see on each router everyone else, so the initialization is done correctly but somehow data packages aren't transferred correctly. There are no invalid iptables rules nor any other firewall is set. 

Regards