At times, you might need to move replication pairs handled by one process service Replication Engine to another process service Replication Engine. This is called process service failover.
Figure 1: Process server before failover
In the preceding image, the primary server is actively managing the replication pair, an the backup process server is idle.
Figure 2: Process server after failover
In the preceding image, the primary server is actively managing the replication pair, and the backup process server has taken over the process server, making the backup process server the active process server in the pair.