A cluster is a group of servers that work together as a single unit. They provide the ability to handle heavy client load and balance the activity across the members that make up the cluster. In EAServer, clustering is implemented in an internal software based mechanism.
The ability to create a cluster, synchronize and balance load are one of the essential functionalities that an application server must provide. An enterprise is more likely to host its critical applications in a cluster rather than on a standalone application server. This is because critical applications need to be running round the clock providing reasonable response times to the clients. This paper discusses the high level concepts involved in an EAServer cluster. It also delves into the concepts behind synchronizing components across members of a cluster, balancing load and providing high availability. Failover and Partitioning are also briefly discussed.