Siemens SIMATIC PCS 7 Function Manual page 151

6. Select the following check boxes as required:
– Synchronization of Tag Logging after the partner server comes back online
– Synchronization of Alarm Logging after the partner server comes back online
– Online synchronization for Alarm Logging
– Synchronization after process connection error
– WinCC client failover if the process connection is disrupted
7. Click "OK".
Result
The "General" tab in the "Redundancy" dialog can be configured as follows:
Fault-tolerant Process Control Systems (V8.1)
Function Manual, 11/2014, A5E34878832-AA
Advantages of fault-tolerant components
4.5 Operator stations
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