Bird just doesn't want to find OSPF neighbors although they are there and can communicate

18 Oct 2021

      Hi,

I am having big trouble getting Bird/OSPF working. I broke it down to a simple setup:
Point-to-point wireguard link between Node1 (192.168.56.224/31) and Node2 (192.168.56.225/31) using nbma.
There were nothing but troubles with multicast and to avoid all these hassles for now, I directly switched to nbma.

Config Station 1:

protocol ospf test {
        area 0.0.0.0 {
                interface "wg-tun" {
                        cost 10;
                        type nbma;
                        authentication cryptographic;
                        password "VWj3QH8LAtWIzQca";
                        neighbors {
                                192.168.56.225;
                        };
                };
        };
}

Config Station 2:

protocol ospf test {
        area 0.0.0.0 {
                interface "wg-tun" {
                        type nbma;
                        cost 10;
                        authentication cryptographic;
                        password "VWj3QH8LAtWIzQca";
                        neighbors {
                                192.168.56.224;
                        };
                };
        };
}

- Ping from both sides to the other works.

Yet the neighbor table just stay empty:

node1:~# birdc show ospf neighbors
BIRD 1.6.8 ready.
test:
Router ID       Pri          State      DTime   Interface  Router IP
node1:~#

node2~:# birdc show ospf neighbors
BIRD 1.6.8 ready.
test:
Router ID       Pri          State      DTime   Interface  Router IP
node2:~#

Both OSPF Hello are received via tcpdump (see below).

What else can be missed?

Thanks,
Lukas

node1:~# tcpdump -n -vvv -i wg-tun 'proto ospf'
tcpdump: listening on wg-tun, link-type RAW (Raw IP), capture size 262144 bytes
23:41:09.515892 IP (tos 0xc0, ttl 1, id 65434, offset 0, flags [none], proto OSPF (89), length 80)
    192.168.56.224 > 192.168.56.225: OSPFv2, Hello, length 44
        Router-ID 192.168.56.193, Backbone Area, Authentication Type: MD5 (2)
        Key-ID: 1, Auth-Length: 16, Crypto Sequence Number: 0x00012747
        Options [External]
          Hello Timer 10s, Dead Timer 40s, Mask 255.255.255.254, Priority 1
          Designated Router 192.168.56.224
23:41:19.589835 IP (tos 0xc0, ttl 1, id 10125, offset 0, flags [none], proto OSPF (89), length 80)
    192.168.56.225 > 192.168.56.224: OSPFv2, Hello, length 44
        Router-ID 192.168.56.194, Backbone Area, Authentication Type: MD5 (2)
        Key-ID: 1, Auth-Length: 16, Crypto Sequence Number: 0x00209357
        Options [External]
          Hello Timer 10s, Dead Timer 40s, Mask 255.255.255.254, Priority 1
          Designated Router 192.168.56.225

node2:~# tcpdump -n -vvv -i wg-tun 'proto ospf'
tcpdump: listening on wg-tun, link-type RAW (Raw IP), snapshot length 262144 bytes
23:41:29.723176 IP (tos 0xc0, ttl 1, id 2705, offset 0, flags [none], proto OSPF (89), length 80)
    192.168.56.224 > 192.168.56.225: OSPFv2, Hello, length 44
        Router-ID 192.168.56.193, Backbone Area, Authentication Type: MD5 (2)
        Key-ID: 1, Auth-Length: 16, Crypto Sequence Number: 0x00012748
        Options [External]
          Hello Timer 10s, Dead Timer 40s, Mask 255.255.255.254, Priority 1
          Designated Router 192.168.56.224
23:41:39.732903 IP (tos 0xc0, ttl 1, id 12839, offset 0, flags [none], proto OSPF (89), length 80)
    192.168.56.225 > 192.168.56.224: OSPFv2, Hello, length 44
        Router-ID 192.168.56.194, Backbone Area, Authentication Type: MD5 (2)
        Key-ID: 1, Auth-Length: 16, Crypto Sequence Number: 0x00209358
        Options [External]
          Hello Timer 10s, Dead Timer 40s, Mask 255.255.255.254, Priority 1
          Designated Router 192.168.56.225

Bird just doesn't want to find OSPF neighbors although they are there and can communicate

Lukas Haase