7.11 Guide to updating a redundant BATCH server in runtime
7.11.1 Software update (migration)
Information is available in the SIMATIC BATCH product documentation:
● Operating manual 
SIMATIC Process Control System PCS 7; SIMATIC BATCH; 
section 
"Software Update (Migration)."
Failure, switchover and reintegration of high availability components
7.11 Guide to updating a redundant BATCH server in runtime
High Availability Process Control Systems (V9.0)
236 Function Manual, 05/2017, A5E39221836-AA