In my setup with conntrack-sync things works nice except when I need NFSv3.
In /var/log/messages it’s logged:
Mar 3 15:25:39 vyos-01 conntrack-tools: no CT attached to this packet Mar 3 15:25:39 vyos-01 conntrack-tools: failed to process message
I see the packet on the ingress interface but nothing comes on the egress interface. When I disable conntrack-sync it works, but then my failover will be broken.