Standalone servers are ideal for running a single instance of Red Hat JBoss Enterprise Application Platform (JBoss EAP) as a single server. In a standalone server, all settings appear in a single point: the JBOSS_HOME/standalone/configuration/standalone.xml configuration file. Within this file, you can configure different subsystems that comprise the features of this server, such as logging, messaging, and managing data sources.

A standalone server only has one profile defined by default, whereas a managed domain has four defined by default. A profile refers to a set of subsystems and their configurations used by the server.

Running multiple instances of JBoss EAP standalone servers can create several complexities, such as requiring administrators to manage port conflicts, having multiple directories with repeated files, and keeping configuration in sync for each server. To resolve these issues, JBoss EAP can be run in a managed domain. Managed domains are discussed more in depth, later in this course.

Another approach is the use of an automation management tool, such as Ansible. You can centralize the management of a group of standalone servers, by maintaining each XML configuration file with Ansible. This approach is out of the scope of this course.

JBoss EAP standalone server provides the capabilities for clustering and high availability. These features can be configured by using several of the other configuration files provided by JBoss EAP, in addition to standalone.xml.

After installing a JBoss EAP distribution, the standalone directory initially contains the following subdirectories:

configuration/
deployments/
lib/

These directories are essential to start JBoss EAP. Without any of them, JBoss EAP does not start.

After running JBoss EAP the first time, the following subdirectories of standalone are created:

data/
log/
tmp/

The configuration and data directories of a JBoss EAP instance can be separated from the directory where JBoss EAP is installed. This allows users to maintain configurations separate from the installation, making it easier to upgrade to a newer version of JBoss EAP. The separation of the configuration and the data directories allows you to install JBoss EAP binaries just in one location, and run it multiple times on the same machine.

There are two command-line properties that enable users to create this separation between the install directory and the directories used by the running instance:

For example, these properties can be set when running the standalone.sh script to start the JBoss EAP server:

$ ./standalone.sh -Djboss.server.base.dir=/path/to/base/directory \
-Djboss.home.dir=/path/to/home/directory

The port-offset attribute can be changed without editing standalone.xml, by using the jboss.socket.binding.port-offset property on the command line. For example:

$ ./standalone.sh -Djboss.socket.binding.port-offset=10000

The port-offset attribute adds the offset to all the JBoss EAP default ports. Thus, a JBoss EAP instance with a port-offset of 10000, serves the HTTP port through 18080, instead of the regular 8080 port.

By default, JBoss EAP uses the BASE_DIR/configuration/standalone.xml to start up a standalone server. However, an alternative configuration file can be used by passing the file name as a parameter of the standalone.sh script. This approach is useful to customize the configuration file without touching the default configuration files. To use a different configuration file, the --server-config parameter can be used as follows:

$ ./standalone.sh ---server-config standalone-full.xml

You can also use the -c alternative parameter:

$ ./standalone.sh -c standalone-full.xml