Operate a Redundant System

During normal redundant system operation, you must implement several important practices to ensure successful redundant operation:

• Manually synchronize the clocks on both servers on a regular basis to ensure that the data and time stamps associated with the historical data are consistent.

• You can edit batch control system databases only on the active master server.

• If the backup server or network loses communication (its synchronization with the master server), an error message is generated to the Log Viewer. In this case, you should review the hardware or system configuration requirements.

• If a hardware failure occurs during the transition of the status of one or more phases, the batch management system assumes that the control system phase logic is correct. Thus, when the backup server starts, the status for all phases that were running before the failure is read from the control system.

• When you start a backup server, we recommend that the batch control system activity be at the minimal level. This practice ensures the highest degree of accuracy for database synchronization.