Sun Microsystems 820433510 manual Enterprise Server Concepts, Domain Administration Server DAS

Enterprise Server Concepts

Enterprise Server Concepts

The Enterprise Server consists of one or more domains. A domain is an administrative boundary or context. Each domain has an administration server (also called Domain Administration Server or DAS) associated with it and consists of zero or more standalone instances and/or clusters. Each cluster has one or more homogeneous server instances. A server instance is a single Java Virtual Machine (JVM) that runs the Application Server on a single physical machine. Server instances (whether standalone or clustered) in a domain can run on different physical hosts.

This section contains the following topics:

■“Domain” on page 26

■“Domain Administration Server (DAS)” on page 26

■“Usage Profiles” on page 27

■“Cluster” on page 28

■“Node Agent” on page 28

■“Server Instance” on page 29

Domain

A domain is a group of instances that are administered together. However, an application server instance can belong to just one domain. In addition to the administration boundary, a domain provides the basic security structure whereby different administrators can administer specific groups (domains) of application server instances. By grouping the server instances into separate domains, different organizations and administrators can share a single Enterprise Server installation. Each domain has its own configuration, log files, and application deployment areas that are independent of other domains. If the configuration is changed for one domain, the configurations of other domains are not affected.

The Sun GlassFish Enterprise Server installer creates the default administrative domain (named domain1). It also creates an associated domain administration server (named server). You must provide the administration server port number. The default administration server port is 4848. The installer also queries for the administration username and master password. After installation, additional administration domains can be created.

Domain Administration Server (DAS)

Each domain has its own Domain Administration Server (DAS) with a unique port number. The Admin Console communicates with a specific DAS to administer the associated domain. Each Admin Console session allows you to configure and manage the specific domain.

The Domain Administration Server (DAS), is a specially-designated application server instance that hosts the administrative applications. The DAS authenticates the administrator, accepts requests from administration tools, and communicates with server instances in the domain to

26 Sun GlassFish Enterprise Server 2.1 Administration Guide • December 2008