Siemens SIMATIC PCS 7 Operation And Maintenance page 23

The following system variables can be checked on the OS server to determine the
redundancy status of the OS server.
Meaning of the variables
Variable name
@LocalMachineName
@RedundantServerState
Compendium Part D - Operation and Maintenance (V9.0)
Operating Manual, 02/2018, A5E43228948-AA
Meaning
This variable contains the local computer name.
The variable shows the redundancy status of this server. Value = 0 ->
Undefined status (starting value); Value = 1 -> Server is master;
Value = 2 -> Server is standby; Value = 3 -> Server fault; Value = 4 ->
Server is standalone (no redundant mode).
Installing updates and service packs
3.3 Checking plant status
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