Siemens SIMATIC PCS 7 Function Manual

7.7 OS clients
7.7.1 Switchover characteristics OS clients with permanent operability
Functionality
If the connection to the configured OS server is interrupted, the process values on the OS
clients are no longer updated. After successful switchover to the partner server, the process
can be operated again on all OS clients. Other OS clients interconnected with the redundant
OS partner server are not affected by this.
Example configuration
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Permanent operability
If OS Server 1 fails, OS Client 1 is connected to redundant OS Server 2. The identity of the
redundant partner server of OS Server 1 comes from the downloaded server data on the OS
client. OS Client 1 is not available during the switchover to redundant OS Server 2 for a short
time. However, if redundant OS Server 2 is specified as the preferred server for OS Client 2,
you can operate the plant during the switchover from the failed OS Server 1 to redundant OS
Server 2.
Failure, switchover and reintegration of high availability components
7.7 OS clients
High Availability Process Control Systems (V9.0)
Function Manual, 05/2017, A5E39221836-AA 213

Siemens SIMATIC PCS 7 Specifications

General

Brand	Siemens
Model	SIMATIC PCS 7
Category	Control Systems
Language	English