Permanent operability for clients
SFC Visualization supports "permanent operability" for clients. A preferred server configured 
on the client is used as the server. This applies regardless of whether the server is the current 
MASTER or STANDBY. If there is a redundancy failover SFC Visualization reacts in 
accordance with the behavior defined in WinCC.
Configuration
5.12 What you should know about OS Server and OS Client
SFC Visualization (V9.0)
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