If you configured service monitoring on an active-passive HA group (see “Configuring service-based failover”) and either the primary unit or the secondary unit detects a service failure on the primary unit, the primary unit changes its effective HA mode of operation to off, stops processing email, and halts all of its HA processes.

After resolving the problem that caused the failure, you can use the following steps to restart the HA processes on the primary unit.

In this example, resolving this problem could be as simple as reconnecting the cable to the port2 network interface. Once the problem is resolved, use the following steps to restart the stopped primary unit.

If a failover has occurred due to processes being stopped on the primary unit, and the secondary unit is currently acting as the primary unit, you can restore the primary and secondary units to acting in their configured roles. For details, see “click HERE to restore configured operating mode”.