Management and Securuty Server 12.6 SP1, Clustering replaces Replication.
See Clustering in the MSS Administrator Guide.
CAUTION:Before you upgrade and begin to configure Clustering, all servers previously configured for Replication (in earlier versions of Management and Security Server) must be set to Standalone — no Master or Slaves.
To disable Replication on every server configured for replication, begin with the Slave servers. Then, disable Replication on the Master.
In the Administrative Console, click Configure Settings - Replication.
Select the Standalone Server Role. Click Apply.
Repeat steps 1 and 2 for all of the Slave servers and then the Master server.
When all of the servers are set to Standalone, upgrade each server.
When all of the servers are upgraded to MSS 12.6 SP1 or higher, configure a cluster of at least three MSS server.
Follow the Clustering steps in the MSS Administrator Guide.
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