Red Hat JBoss Enterprise Application Platform Administration I
- Section Managed Domain Server Architecture
- Quiz: Hosts and Servers
- Configuring Server Groups
- Guided Exercise: Configuring Server Groups
- Configuring Servers
- Guided Exercise: Configuring Servers
- Deploying Applications on a Managed Domain
- Guided Exercise: Deployment on a Managed Domain
- Lab: Configuring Servers in a Managed Domain
- Summary
Abstract
| Goal |
Configure servers and server groups in a managed domain. |
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| Sections |
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| Lab |
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A Red Hat JBoss Enterprise Application Platform (JBoss EAP) managed domain consists of the following four elements:
- Domain controller
Responsible for all configuration management by using profiles.
- Host controller
Responsible for managing server instances. In a production environment, a host controller is usually installed on a separate physical or virtual machine.
- Server Groups
A logical grouping of JBoss EAP server instances that are configured and managed together as a single unit. Server groups can span any number of servers across multiple host controllers.
- Server
Responsible for running Jakarta EE applications: JAR, EAR, and WAR files.
To simplify server instance management, JBoss EAP defines the concept of a server group. A server group shares the same set of applications, and reuses the same profile and all embedded configurations.
Note
A server cannot be part of multiple server groups.
Server groups are configured in the domain.xml configuration file on the domain controller.
Servers are configured in the host.xml configuration file on each host.
The topology of an JBoss EAP managed domain can be viewed from two perspectives:
- Host View
A managed domain consists of various hosts, where a host is a JBoss EAP instance running in managed domain mode. A JBoss EAP managed domain is a collection of hosts.
- Server View
A JBoss EAP managed domain can be viewed as a collection of server instances. Each server instance belongs to a server group.
The following diagram shows a domain from the perspective of the hosts within the managed domain:
The previous diagram shows which servers are running on a host, without addressing which server groups each one belongs to. In the host view, it is hard to identify which servers share the same configuration set, but it is useful for an administrator to see how many processes are running on each machine. An administrator can plan the amount of memory and CPU capacity needed for each host based on this information.
The following diagram shows the same JBoss EAP managed domain from the perspective of the servers:
The previous diagram shows the servers, and the server group they belong to, providing a logical view of the JBoss EAP managed domain. The server view does not address hardware concerns, but shows which servers share the same configuration set. Notice that in the server view, the important distinction is the server group, and not the machine that the server is running on. When designing a managed domain, the server view is critical because applications are not deployed onto servers; they are deployed onto server groups.
These views complement each other and can help an administrator to plan how many JBoss EAP host controllers must be deployed and how many servers must be created.
Note
Different server groups can be configured with different profiles and deployments. Different server groups can run the same profile and have the same deployments. A benefit of having identical server groups is to support rolling application upgrade scenarios, where a complete service outage is avoided by first upgrading the application on one server group, and then upgrading the application on the second server group.
References
For more information about configuring the server in JBoss EAP domain mode, refer to the Managing Servers section in the Configuration Guide in the Red Hat JBoss EAP documentation at https://access.redhat.com/documentation/en-us/red_hat_jboss_enterprise_application_platform/7.4/html-single/configuration_guide/index#managing_servers
