In redundant systems, it is common to require that a particular Server in the RedundantServerSet be taken out of the RedundantServerSet for a period of time. Some items that could cause this may include:

• Certificate update
• Security reconfiguration
• Rebooting or restarting of the machine for
• software updates and patches
• installation of new software
• Reconfiguration of the AddressSpace

The removal from the RedundantServerSet can be done through a complete shutdown or by setting the ServiceLevel of the Server to Maintenance sub-range. This can be done through a Server specific configuration tool or through the Method RequestServerStateChange on the ServerType. The Method is formally defined in OPC 10000-5.

This Method requires that the Client provide credentials with administrative rights on the Server.