Sun Java Enterprise System 2005Q4 Installation Planning Guide

Redundancy Strategies

Most solutions intended for production use include some type of redundancy. Redundancy strategies use multiple instances of a component to provide a single service. Redundancy is used to satisfy quality of service requirements. For example, redundancy is used to increase throughput in order to satisfy performance requirements, or to avoid a single point of failure to in order satisfy reliability requirements.

Three strategies are available for using redundant instances of Java ES components: load balancing, clustering with Sun Cluster software, and Directory Server multi-master replication. The recommended installation and configuration procedure for each of these strategies is outlined briefly in the following paragraphs:

When your deployment architecture uses any of these redundancy strategies, you must develop a plan for installing multiple instances of a component and configuring the instances to operate as a single service.