The updating of your redundant operator stations is complete.
Note
Encrypted communication 
If you have used encrypted communication, it is activated in migration mode for all PC stations 
in the system. Use encrypted communication in migration mode only as a temporary solution. 
Deactivate migration mode in the entire system. You can find information about this in the 
documentation 
Process Control System PCS 7; PCS 7 PC Configuration
.
7.10.3 Phase 1: Updating Server_2
Introduction         
In the first phase, you update redundant Server_2. In this way, you avoid an unnecessary 
switchover for OS clients that have no preferred server configured. 
You can find additional information about redundancy synchronization in 
WinCC Information 
System
 > 
Configurations > Redundant Systems
.
During the steps involved in Phase 1, your system continues to work with only one server. The 
system remains controllable from the OS clients that have not yet been updated. If this server 
fails, the automation system can no longer be controlled.
NOTICE
Interrupted redundancy
Perform the steps without extended interruptions because the redundancy is not available 
during the update.
Initial situation before phase 1
● Server_1 is master server.
● Server_2 is standby server.
● Client_1 is connected to Server_1.
● Client_2 is connected to Server_2 because this server is configured as its preferred server.
Requirements
● The PCS 7 project you are updating has already been updated on the ES.
● When using an archive server:
– Synchronization of the archive must be complete to ensure that the process data (RT 
data) is consistent.
Failure, switchover and reintegration of high availability components
7.10 Guide to updating a redundant OS in runtime
High Availability Process Control Systems (V9.0)
224 Function Manual, 05/2017, A5E39221836-AA