Rafael Torres of BEA will speak on:
Application Server Clusters
A WebLogic Server cluster is a group of servers that work together to provide a more scalable, more reliable application platform than a single server. A cluster appears to its clients as a single server but is in fact a group of servers acting as one. A cluster provides two key features above a single server:
1. Scalability: The capacity of a cluster is not limited to a single server or a single machine. New servers can be added to the cluster dynamically to increase capacity. If more hardware is needed, a new server on a new machine can be added. If a single server cannot fully utilize an existing machine, additional servers can be added to that machine.
2. High-Availability: A cluster uses the redundancy of multiple servers to insulate clients from failures. The same service can be provided on multiple servers in the cluster. If one server fails, another can take over. The ability to failover from a failed server to a functioning server increases the availability of the application to clients. WebLogic Server clusters are designed to bring scalability and high availability to J2EE applications. They provide these features in a way that is transparent to the application writer and to clients. It is important, however, for application programmers and administrators to understand the issues inherent in clustering in order to maximize the scalability and availability of their applications.