You can start the OPC Mirror Configuration program on the Application Station where the active OPC Mirror is running to define pipes or set server monitor configuration options. To start the OPC Mirror Configuration program, click or right-click the OPC Mirror icon 
in the System Tray, and then select Configure.
After defining any pipes, you must exit the OPC Mirror Configuration program before they are activated and copied to the standby OPC Mirror.
You cannot run the OPC Mirror Configuration program on the Application Station where the standby OPC Mirror is running. Any configuration settings you make for the active OPC Mirror are automatically migrated to the standby OPC Mirror.
Configuration settings are stored in a configuration database file containing a last-changed timestamp value (in GMT or UTC) and a sequential configuration-changed value. These values appear in the status bar of the OPC Mirror Configuration program as LastChangedTime and SequenceNumber. After a switchover, OPC Mirror uses these values to synchronize the configuration databases of the active and standby OPC Mirror for redundancy. If the LastChangedTime and SequenceNumber values of both configuration databases match exactly, the configuration databases are in sync. If the configuration databases are out of sync, the configuration database with the most current SequenceNumber value is used to synchronize the configuration databases, unless the SequenceNumber values are the same. In this case, the configuration database with the most current LastChangedTime value is used.