If you plan to build a scalable and highly available Website, you need to understand clustering. Abraham Kang introduces J2EE clustering, shows how to implement clusters, and examines how application servers from Bluestone, Sybase, SilverStream, and BEA differ in their approaches.
Such details as failover, replication, scalability and performance are dicussed, along with how four vendors implement clustering in their respective products is discussed.
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The Middleware Company