In this chapter, we looked at a lot of configuration options around clustering. There was a lot of information to take in but, in summary, we will mention the following key points.

A WildFly cluster can be composed of either standalone nodes or as part of a domain of servers .The clustering subsystem is defined in the standalone-ha.xml and standalone-full-ha.xml configurations files.

There are three main components required for clustering: JGroups, Infinispan, and messaging. JGroups provides communication between nodes in a cluster. By default, JGroups uses UDP multicast messages to handle the cluster life cycle events.

Within enterprise applications, there are several caches that need to be configured in order to achieve consistency of data. There are four cache containers configured by default in WildFly. These are the singleton session bean cluster cache-container, the SLSB cache-container, the web cache-container, and the Hibernate cache-container.

The singleton cluster (server)...