Data Replication and Failover Protection

When you install an MCS server cluster, all configuration changes take place through the cluster's primary server. Data, such as applications and event logs, is dynamically replicated across all servers in the cluster, either every ten minutes or when data is changed through the primary server, ensuring that all active servers have access to the latest data.

When a change is made through the primary server, MCS notifies all other servers to start replication. This replication occurs after a one minute delay so that multiple changes can be replicated at the same time. This optimizes replication, but it also means that the servers can be out of sync for 60 seconds or longer while the replication process completes.

You can use the MCS console to find out which server is currently acting as the primary server, and to change the priority of servers in the cluster to reassign primary server responsibilities to a different server. For more information, see the topic, Viewing Server Information.

Failover Protection

The status of the primary server is monitored by a managed service in MCS. If the primary server ever goes off-line, the server with next highest priority in the cluster takes over primary server responsibilities. Several things happen to minimize data loss and ensure the availability of MCS:

Unless the priority of the primary server is changed through the MCS console, when the original primary server comes back on-line, it resumes primary server responsibilities.

Related Topics
Bullet Managing MCS Servers and Clusters
Bullet Configuring Failure Detection
Bullet Managed Services in MCS