It includes the following sections:
A WebLogic domain is the basic administrative unit of WebLogic Server. It consists of one or more WebLogic Server instances, and logically related resources and services that are managed collectively as one unit.
As shown in Figure 1-1, the basic domain infrastructure consists of one Administration Server and optional Managed Servers and clusters.
The components of a WebLogic domain are described in Table 1-1.
A domain includes one WebLogic Server instance that is configured as an Administration Server. All changes to configuration and deployment of applications are done through the Administration Server.
The Administration Server provides a central point for managing the domain and providing access to the WebLogic Server administration tools. These tools include the following:
For more information about the WebLogic Server administration tools, see "Summary of System Administration Tools and APIs" in Introduction to Oracle WebLogic Server.
All other WebLogic Server instances in a domain are called Managed Servers. Managed Servers host application components and resources, which are also deployed and managed as part of the domain. In a domain with only a single WebLogic Server instance, that single server works as both the Administration Server and the Managed Server.
A domain may also include WebLogic Server clusters, which are groups of Managed Server instances that work together to provide scalability and high availability for applications. Clusters can improve performance and provide failover when a server instance becomes unavailable. The servers within a cluster can either run on the same machine or reside in different machines. To the client, a cluster appears as a single WebLogic Server instance.
Note:All Managed Servers in a domain must run the same version of WebLogic Server. The Administration Server can run either the same version as the Managed Servers in the domain, or a later service pack.
In addition to infrastructure components, a domain defines the basic network configuration for the server instances that it contains. Specifically, a domain defines application deployments, supported application services (such as database and messaging services), security options, and physical host machines.
Domain configuration information is stored in the configuration directories under the domain directory.
You might find it useful to configure multiple WebLogic Domains based on specific criteria, such as system administrator responsibilities, the logical classification of applications, the geographical locations of servers, or size. The following table outlines the most common domain configurations.
Domain with Managed Servers
In typical production environments, several Managed Servers can host applications, and an Administration Server performs management operations.
Domain with Managed Servers and clusters
In production environments that require increased performance, throughput, or availability for an application, several Managed Servers might be grouped in a cluster.
In such a case, the WebLogic domain consists of one or more clusters with the applications they host, additional Managed Servers (if necessary), and an Administration Server to perform management operations.
Standalone server domain
In development or test environments, a single application server might be deployed independently without Managed Servers. In such a case, you can have a WebLogic domain consisting of a single Administration Server that also hosts the applications you want to test or develop.
Note:In production environments, Oracle recommends that you deploy applications only on Managed Servers, and that you reserve the Administration Server for management tasks.
For more information about WebLogic domains, see "Understanding Oracle WebLogic Server Domains" in Understanding Domain Configuration for Oracle WebLogic Server
Before you can develop and run an application on a WebLogic domain, you must first create the WebLogic domain. The Configuration Wizard (illustrated in Figure 1-2), simplifies the process of creating and extending a domain.
To create or extend a WebLogic domain by using the Configuration Wizard, you simply select the product components (product templates) to be included in the domain (or choose a template that best meets your requirements), and provide basic configuration information. The Configuration Wizard then creates or extends the domain by adding the resources defined in the selected product templates.
For more information about templates, see About Domain and Extension Templates.
After you use the Configuration Wizard to create a WebLogic domain, you can start a WebLogic Server instance in the domain to develop, test, and deploy applications.
Note:The Domain Template Builder tool simplifies the process of creating templates by guiding you through the process of creating custom domain and extension templates. You can select these templates to create and extend domains either by using the Configuration Wizard or the WebLogic Scripting Tool (WLST). For information about the Domain Template Builder, see Creating Domain Templates Using the Domain Template Builder. For information about creating domains using WLST, see "Creating Domains Using WLST Offline" in Oracle WebLogic Scripting Tool.
You can use the Configuration Wizard can only when there is no server running. It supports the following modes of operation:
Graphical mode: An interactive, GUI-based mode
Console mode: An interactive, text-based mode
Note:For a scripted, silent-mode method, you can use WLST. For more information, see Oracle WebLogic Scripting Tool.
A WebLogic domain that was created using the Configuration Wizard has the following directories:
autodeploy: This directory provides a location from which you can deploy applications quickly on a development server. When the WebLogic Server instance is running in development mode, it automatically deploys any applications or modules that you place in this directory.
bin: This directory contains scripts to start and stop the Administration Server, and, optionally, Managed Servers.
config: This directory contains:
A domain-specific configuration file,
config.xml, that specifies the name of the WebLogic domain and the configuration parameter settings for each server instance, cluster, resource, and service in the domain.
Subdirectories that contain the configuration for various system modules:
security. These subdirectories contain configuration files that are incorporated, by reference, into the
Note:Depending on your configuration, some subdirectories may not exist.
console-ext—This directory contains console extensions used by the Administration Server.
init-info: This directory contains files used by the Configuration Wizard to support creation and extension of the WebLogic domain.
lib: This directory contains the domain library. When the server starts, any
jar files that you place in this directory are dynamically added to the end of the server classpath.
security: This directory contains common security files for all the servers in the domain.
servers: This directory contains a subdirectory for each server in the domain. These server subdirectories, in turn, contain subdirectories that hold directories and files specific to each server in a WebLogic domain, such as
user_staged_config: If the domain is configured to be user-staged, that is, the administrator is responsible for staging (copying) the configuration information to the Managed Servers, this directory provides an alternative to the
If the template used to create a WebLogic domain includes applications, the application files are located, by default, in
For more information, see "Domain Configuration Files" in Understanding Domain Configuration for Oracle WebLogic Server
In the context of the Configuration Wizard, the term template refers to a Java Archive (JAR) file, which contains the files and scripts required to create or extend a WebLogic domain. The types of templates that the Configuration Wizard uses to create or extend WebLogic domains include:
Domain template: This type of template defines the full set of resources within a WebLogic domain, including infrastructure components, applications, services, security options, and general environment and operating system options. You can create this type of template from an existing WebLogic domain by using the Domain Template Builder tool or the
pack command. Subsequently, you can create a WebLogic domain based on the template by using the Configuration Wizard.
The product distribution includes a base WebLogic domain template. A domain template defines the core set of resources within a domain, including
An Administration Server and basic configuration information
General environment and operating system requirements.
A domain template does not include sample applications. You can use a domain template to create a basic WebLogic domain, which you can then extend with applications and services, or additional product components.
Extension template: Whereas a domain template can create a self-sufficient WebLogic domain, you use an extension template to add functionality to an existing domain. In the Configuration Wizard, before selecting the extension template to use, you must select the WebLogic domain you want to extend.
Managed Server template: This type of template defines the subset of resources, within a WebLogic domain, that are required to create a Managed Server domain on a remote machine. You can create this type of template by using the
The WebLogic Server product installation includes a set of predefined domain and extension templates. This set includes the base WebLogic domain template and various extension templates that allow you to add component features and samples to the base domain. For more information about these templates and how they relate to each other, see Oracle WebLogic Server Domain Template Reference.
In addition to the Configuration Wizard, you can use the tools listed in Table 1-3 to create, extend, and manage domains. You can also perform run-time configuration by using the consoles of the product components (for example, the WebLogic Server Administration Console).
|To do this||Use the following tools|
Create a WebLogic domain or extend an existing domain
Add applications and services, or modify existing settings
Manage and monitor the health and status of the domain