Spooler replication and failovers

Within the active system, information is replicated from the hot computer to the standby computer. This guarantees that messages are not lost within the active system on a service failover.

If the service fails over, the Hot computer continues the event logging. The event queue is re-synchronized periodically via replication. The actual printing of the messages is the responsibility of the spooler at the Hot Service. The spooler on the Standby Service idles while it waits to take over.

There is no guarantee that there will not be message loss on system failover (for example, failover to the backup system). It is possible to lose messages since the spooler configuration (for example, the list of named physical devices associated with each spooler) is automatically replicated between different systems, but the state information and the message queue are not.