OSPFv2 Neighbour not forming

Hi,

I'm working on the basis that I'm doing something stupid but here we go :)...

Lab environment, VMWare Workstation, 14.1.2 LTM VE <-> VyOs Router, LTM vLAN EXT_1, SelfIP 100.100.100.100/24, VyOS IP 100.100.100.1/24.

LTM can ping VyOS:

# ping -I EXT_1 100.100.100.1

PING 100.100.100.1 (100.100.100.1) from 100.100.100.100 EXT_1: 56(84) bytes of data.

64 bytes from 100.100.100.1: icmp_seq=1 ttl=255 time=2.18 ms

64 bytes from 100.100.100.1: icmp_seq=2 ttl=255 time=1.46 ms

64 bytes from 100.100.100.1: icmp_seq=3 ttl=255 time=0.519 ms

^C

--- 100.100.100.1 ping statistics ---

3 packets transmitted, 3 received, 0% packet loss, time 2002ms

rtt min/avg/max/mdev = 0.519/1.390/2.184/0.682 ms

VyOS can also ping LTM.

OSPF enabled on VyOS Router, show ip ospf on VyOS shows neighbour with F5 stuck in INIT, which indicates VyOS is receiving HELLOs from F5.

OSPF enabled on F5, show ip ospf neighbour shows nothing, and show ip ospf interfact EXT_1 indicates no HELLO packets received:

#show ip ospf neighbor

OSPF process 1:

Neighbor ID    Pri  State           Dead Time  Address        Interface

#show ip ospf interface EXT_1

EXT_1 is up, line protocol is up

 Interface ID 144

 Host Interface ID 10

 Internet Address 100.100.100.100/24, Area 0.0.0.0, MTU 1500

 Process ID 1, Router ID 100.100.100.100, Network Type BROADCAST, Cost: 10

 Transmit Delay is 1 sec, State DR, Priority 1

 Designated Router (ID) 100.100.100.100, Interface Address 100.100.100.100

 No backup designated router on this network

 Timer intervals configured, Hello 1, Dead 3, Wait 3, Retransmit 5

   Hello due in 00:00:01

 Neighbor Count is 0, Adjacent neighbor count is 0

 Crypt Sequence Number is 3250

 Hello received 0 sent 5146, DD received 0 sent 0

 LS-Req received 0 sent 0, LS-Upd received 0 sent 0

 LS-Ack received 0 sent 0, Discarded 0

Running tcpdump on F5 (100.100.100.100), I can see OSPF HELLO's from VyOS (100.100.100.1) received on both data plane and tmm (hello 1 sec, dead 3 sec):

# tcpdump -ni 0.0:nnn -s0 -vv host 100.100.100.1

tcpdump: listening on 0.0:nnn, link-type EN10MB (Ethernet), capture size 65535 bytes

13:54:34.484733 IP (tos 0xc0, ttl 1, id 64651, offset 0, flags [none], proto OSPF (89), length 68)

   100.100.100.1 > 224.0.0.5: OSPFv2, Hello, length 48

       Router-ID 2.2.2.2, Backbone Area, Authentication Type: none (0)

       Options [External]

         Hello Timer 1s, Dead Timer 3s, Mask 255.255.255.0, Priority 1

         Designated Router 100.100.100.1

         Neighbor List:

           100.100.100.100 in slot1/tmm0 lis= flowtype=0 flowid=0 peerid=0 conflags=0 inslot=63 inport=23 haunit=0 priority=0 peerremote=00000000:00000000:00000000:00000000 peerlocal=00000000:00000000:00000000:00000000 remoteport=0 localport=0 proto=0 vlan=0

13:54:35.486675 IP (tos 0xc0, ttl 1, id 64652, offset 0, flags [none], proto OSPF (89), length 68)

   100.100.100.1 > 224.0.0.5: OSPFv2, Hello, length 48

       Router-ID 2.2.2.2, Backbone Area, Authentication Type: none (0)

       Options [External]

         Hello Timer 1s, Dead Timer 3s, Mask 255.255.255.0, Priority 1

         Designated Router 100.100.100.1

         Neighbor List:

           100.100.100.100 in slot1/tmm0 lis= flowtype=0 flowid=0 peerid=0 conflags=0 inslot=63 inport=23 haunit=0 priority=0 peerremote=00000000:00000000:00000000:00000000 peerlocal=00000000:00000000:00000000:00000000 remoteport=0 localport=0 proto=0 vlan=0

13:54:36.485903 IP (tos 0xc0, ttl 1, id 64653, offset 0, flags [none], proto OSPF (89), length 68)

   100.100.100.1 > 224.0.0.5: OSPFv2, Hello, length 48

       Router-ID 2.2.2.2, Backbone Area, Authentication Type: none (0)

       Options [External]

         Hello Timer 1s, Dead Timer 3s, Mask 255.255.255.0, Priority 1

         Designated Router 100.100.100.1

         Neighbor List:

           100.100.100.100 in slot1/tmm0 lis= flowtype=0 flowid=0 peerid=0 conflags=0 inslot=63 inport=23 haunit=0 priority=0 peerremote=00000000:00000000:00000000:00000000 peerlocal=00000000:00000000:00000000:00000000 remoteport=0 localport=0 proto=0 vlan=0

port-lockdown on EXT_1 is set to permit default (have tried permit all - no difference).

NB: I thought there may be an issue in VM Workstation with multicast but I set up a 2nd VyOS router on the same vLAN - This forms a FULL OSPF peering with the original VyOS device, and again INIT with the F5. Have also confirmed MTUs on F5 and VyOS etc. all match.

The issue is the routing process on the F5 is not receiving the OSPF HELLO's fom the VyOS (as observed from show ip ospf interface output) but tcpdump shows the OSPF HELLO packets are received at the network level.

Any thoughts? Many Thanks!