CLUSTERS

Example of clustering two servers for mail and applications
If you have only two servers in your cluster, you can set them up in one of two ways: You can use one of the servers as the primary server for user access and use the second server as a backup and failover server, or you can equally divide the workload between the two servers and have them fail over to each other. Dividing the workload typically ensures better performance when both servers are running. When one server is not available, performance is the same in both scenarios because one server must process the entire workload of both servers.

The following figure shows a cluster with two servers with the workload divided between the servers.

Two-server cluster for mail and applications