bird> s interfaces 
lo up (index=1)
        MultiAccess AdminUp LinkUp Loopback Ignored MTU=65536
        45.225.75.241/32 (Primary, scope univ)
        127.0.0.1/8 (Unselected, scope host)
ens18 up (index=2)
        MultiAccess Broadcast Multicast AdminUp LinkUp MTU=1500
        23.152.224.172/24 (Primary, scope univ)
tap0 up (index=3)
        MultiAccess Broadcast Multicast AdminUp LinkUp MTU=1420
        172.30.125.1/24 (Primary, scope site)
backup up (index=5)
        PtP Multicast AdminUp LinkUp MTU=1420
        172.30.128.0/31 (Primary, opposite 172.30.128.1, scope site)
bird> s ospf interface 
main:
Interface tap0 (172.30.125.0/24)
        Type: broadcast
        Area: 0.0.0.0 (0)
        State: Backup
        Priority: 1
        Cost: 10000
        Hello timer: 1
        Wait timer: 4
        Dead timer: 10
        Retransmit timer: 5
        Designated router (ID): 172.20.0.9
        Designated router (IP): 172.30.125.2
        Backup designated router (ID): 23.152.224.172
        Backup designated router (IP): 172.30.125.1
Interface backup (172.30.128.0/31)
        Type: broadcast
        Area: 0.0.0.0 (0)
        State: DR
        Priority: 1
        Cost: 10001
        Hello timer: 1
        Wait timer: 4
        Dead timer: 10
        Retransmit timer: 5
        Designated router (ID): 23.152.224.172
        Designated router (IP): 172.30.128.0
        Backup designated router (ID): 172.20.0.12
        Backup designated router (IP): 172.30.128.1
bird> s ospf neighbors 
main:
Router ID       Pri          State      DTime   Interface  Router IP   
172.20.0.9        1     Full/DR         00:10   tap0       172.30.125.2   
172.20.0.12       1     Full/BDR        00:09   backup     172.30.128.1