Virtual servers are grouped into classes. Using classes you can configure similar virtual servers at the same time, so you don’t have to configure each one separately. Though all virtual servers in a class share the same basic configuration information, you can also set variables and change configuration per virtual server. If you do not want virtual servers to share configuration information, you can create a single virtual server for every virtual server class. However, if your virtual servers share similar properties, you can group them in a class and configure them together.
For example, if you work for an Internet Service Provider (ISP) and want to provide different levels of hosting for different customers at different prices, you can set up several classes of virtual servers for your customers. You might enable Java servlets and JSPs for one class of virtual servers, and disable Java servlets and JSPs for a less expensive class of virtual servers.
You create a class of virtual servers by naming it and setting up a document root, where all virtual servers belonging to the class will have their document roots by default. You can use the $id variable so that each virtual server within the class will have a separate document root within the class’ document root. For more information, see Document Root.
After creating the class of virtual servers, you associate services with it. You can turn on or configure the following types of services for a class of virtual servers:
Programs, see Chapter 16, Extending Your Server With Programs.
Content Management, see Chapter 17, Content Management.
Configuration Styes, see Chapter 18, Applying Configuration Styles.
All virtual servers in a class share an obj.conf file, which stores information about the virtual server class. Some of that information is stored in variables, so that individual virtual servers can have specific variable values substituted on the fly.
For more information about obj.conf and variables, see the Sun Java System Web Server 6.1 SP9 NSAPI Programmer’s Guide. For more information on using variables in the user interface, see Using Variables.
A virtual server that belongs to a class is called a member of that class. Some virtual server settings are configured for all virtual servers in a class, and some are configured individually. These settings are configured on the Class Manager’s Virtual Servers tab. For more information, see Chapter 15, Creating and Configuring Virtual Servers.
When you install Sun Java System Web Server, the installer automatically creates a single class, called defaultclass. It contains one virtual server member, by default, for your server instance. You can add additional virtual servers to the default class, but you cannot delete your default virtual server from the class. You also cannot delete the default class.