NSX 6.2.3 uses Bidirectional Forwarding Detection (BFD) to detect High Availability (HA) node availability.
If HA nodes are run for 24 days, BFD goes down and get stuck in an init state. In this state, the node is unable to send BFD control packets but it continues to receive them.
When BFD is down, as a backup mechanism, ARP probes are sent through other interfaces to detect if the other node is still reachable. If there is a response, nodes continues to stay in an Active Standby state and no issues are experienced. If there is no response, then the Standby node moves to an Active state.
When two HA nodes are in an Active Active state, it is known as Split Brain and can result in network disruption. This configuration state remains until corrective action is taken to bring BFD back up
When two HA nodes are in an Active Active state, it is known as Split Brain and can result in network disruption. This configuration state remains until corrective action is taken to bring BFD back up.