In the previous chapter, we illustrated the first important advantage of clustered applications, which is the ability to maintain unaffected services for any predefined number of clients. It is also known as high availability.
In this chapter, we will cover the second main concern of clustering, which is the ability to make several servers participate in the same service and do the same work. In other words, how to load-balance the number of requests across the available servers.
Historically, the JBoss AS has inherited the load-balancing libraries from his "cousin" Tomcat, which is itself a part of the application server modules. This module,
mod_jk, is still available for use in the new application server ...