Yes, ML2/OVN with HW offload. I have some questions: * Are you using FIPs? No * Did you try pinging another IP on the external network? Yes, other IPs work (the destination IP is a VRR on Cumulus Linux switch) * In your deployment, do you have [1]? Yes I do, I did run ovn sync util after updating to a version containing that before raising the bug * Related to the last point, what is the router configuration? Network attached, type, etc. The router it outside of OpenStack/Neutron (VRR on Cumulus Linux switch) * Do you have HA? How many controllers do you have? I'm assuming the GW is in one of these controllers. 3 controllers, but the GW is not on them * Did you do a full trace of the ICMP packets? I mean, tracking the packet from the VM, though the compute node interface, the switch, the controller HW interface, the controller GW port, etc. Yes, I did tracing on: 1) ens0f1_6 (HW offload instance port) (first one/two replies, then nothing) listening on ens1f0_6, link-type EN10MB (Ethernet), capture size 262144 bytes 11:09:02.305764 fa:16:3e:34:dd:93 > 00:00:5e:00:01:12, ethertype IPv4 (0x0800), length 98: 10.1.112.89 > 10.1.112.254: ICMP echo request, id 14, seq 1, length 64 11:09:02.307805 1c:34:da:b0:97:68 > fa:16:3e:34:dd:93, ethertype IPv4 (0x0800), length 98: 10.1.112.254 > 10.1.112.89: ICMP echo reply, id 14, seq 1, length 64 11:09:03.307190 fa:16:3e:34:dd:93 > 00:00:5e:00:01:12, ethertype IPv4 (0x0800), length 98: 10.1.112.89 > 10.1.112.254: ICMP echo request, id 14, seq 2, length 64 11:09:03.307912 1c:34:da:b0:97:68 > fa:16:3e:34:dd:93, ethertype IPv4 (0x0800), length 98: 10.1.112.254 > 10.1.112.89: ICMP echo reply, id 14, seq 2, length 64 11:09:04.308288 fa:16:3e:34:dd:93 > 00:00:5e:00:01:12, ethertype IPv4 (0x0800), length 98: 10.1.112.89 > 10.1.112.254: ICMP echo request, id 14, seq 3, length 64 11:09:05.313646 fa:16:3e:34:dd:93 > 00:00:5e:00:01:12, ethertype IPv4 (0x0800), length 98: 10.1.112.89 > 10.1.112.254: ICMP echo request, id 14, seq 4, length 64 11:09:06.337654 fa:16:3e:34:dd:93 > 00:00:5e:00:01:12, ethertype IPv4 (0x0800), length 98: 10.1.112.89 > 10.1.112.254: ICMP echo request, id 14, seq 5, length 64 11:09:07.361663 fa:16:3e:34:dd:93 > 00:00:5e:00:01:12, ethertype IPv4 (0x0800), length 98: 10.1.112.89 > 10.1.112.254: ICMP echo request, id 14, seq 6, length 64 11:09:08.385652 fa:16:3e:34:dd:93 > 00:00:5e:00:01:12, ethertype IPv4 (0x0800), length 98: 10.1.112.89 > 10.1.112.254: ICMP echo request, id 14, seq 7, length 64 11:09:09.409641 fa:16:3e:34:dd:93 > 00:00:5e:00:01:12, ethertype IPv4 (0x0800), length 98: 10.1.112.89 > 10.1.112.254: ICMP echo request, id 14, seq 8, length 64 11:09:10.433645 fa:16:3e:34:dd:93 > 00:00:5e:00:01:12, ethertype IPv4 (0x0800), length 98: 10.1.112.89 > 10.1.112.254: ICMP echo request, id 14, seq 9, length 64 11:09:10.786348 1c:34:da:b0:97:68 > fa:16:3e:34:dd:93, ethertype IPv4 (0x0800), length 62: 10.1.112.252 > 10.1.112.89: ICMP echo reply, id 1540, seq 1, length 28 11:09:11.457645 fa:16:3e:34:dd:93 > 00:00:5e:00:01:12, ethertype IPv4 (0x0800), length 98: 10.1.112.89 > 10.1.112.254: ICMP echo request, id 14, seq 10, length 64 2) tap53e35d44-27 (request packets arriving) 11:08:22.433669 fa:16:3e:34:dd:93 > 00:00:5e:00:01:12, ethertype IPv4 (0x0800), length 98: 10.1.112.89 > 10.1.112.254: ICMP echo request, id 13, seq 179, length 64 11:08:23.457669 fa:16:3e:34:dd:93 > 00:00:5e:00:01:12, ethertype IPv4 (0x0800), length 98: 10.1.112.89 > 10.1.112.254: ICMP echo request, id 13, seq 180, length 64 11:08:24.481684 fa:16:3e:34:dd:93 > 00:00:5e:00:01:12, ethertype IPv4 (0x0800), length 98: 10.1.112.89 > 10.1.112.254: ICMP echo request, id 13, seq 181, length 64 11:08:25.505683 fa:16:3e:34:dd:93 > 00:00:5e:00:01:12, ethertype IPv4 (0x0800), length 98: 10.1.112.89 > 10.1.112.254: ICMP echo request, id 13, seq 182, length 64 3) bond0 (external port) listening on bond0, link-type EN10MB (Ethernet), capture size 262144 bytes 11:10:14.515228 fa:16:3e:34:dd:93 > 00:00:5e:00:01:12, ethertype 802.1Q (0x8100), length 102: vlan 112, p 0, ethertype IPv4, 10.1.112.89 > 10.1.112.254: ICMP echo request, id 15, seq 1, length 64 11:10:14.515452 1c:34:da:b0:97:68 > fa:16:3e:34:dd:93, ethertype 802.1Q (0x8100), length 102: vlan 112, p 0, ethertype IPv4, 10.1.112.254 > 10.1.112.89: ICMP echo reply, id 15, seq 1, length 64 Basically when I stop one of the instances - then everything works as it should.