The concept of a domain mode might be perceived as a little difficult to understand. The reason for this is that in the Java EE paradigm, one is used to dealing with servers rather than domains.

Basically, a domain is a group of WildFly servers managed by one of the servers. The server managing the domain is called the domain controller. This group is under one administration—it is the administrative unit. It's important to understand that the concept of a domain does not interfere with the capabilities delivered by the managed servers. For example, you might set up a domain of application server nodes running in a cluster, providing load balancing and high availability. However, you can also achieve the same outcome with a set of standalone application servers.

What differentiates these two scenarios is that when running in a domain, you can efficiently manage your set of servers from a single, centralized unit. On the other hand, managing a set of standalone...