Virtual host collection

To create and manage configurations that each let a single host machine resemble multiple host machines. Such configurations are known as virtual hosts.

To view this admin console page, click Environment > Virtual hosts.

Each virtual host has a logical name (which you define on this panel) and is known by its list of one or more DNS aliases. A DNS alias is the TCP/IP host name and port number used to request the servlet, for example theHostName:80. (Port 80 is the default.)

You define one or more alias associations by clicking an existing virtual host or by adding a new virtual host.

When a servlet request is made, the server name and port number entered into the browser are compared to a list of all known aliases in an effort to locate the correct virtual host to serve the servlet. No match returns an error to the browser.

An appserver profile provides a default virtual host with some common aliases, such as the internet protocol (IP) address, the DNS short host name, and the DNS fully qualified host name. The alias comprises the first part of the path for accessing a resource such as a servlet.

For example, the alias is localhost:80 in the request http://localhost:80/myServlet.

A virtual host is not associated with a particular profile or node (machine), but is associated with a particular server instead. It is a configuration, rather than a "live object." We can create a virtual host, but we cannot start or stop it.

For many users, creating virtual hosts is unnecessary because the default_host that is provided is sufficient.

Add the host name and IP address of the localhost machine to the alias table lets a remote user access the admin console.

Resources associated with one virtual host cannot share data with resources associated with another virtual host, even if the virtual hosts share the same physical machine.

Name

Logical name for configuring Web apps to a particular host name. The default virtual host is suitable for most simple configurations.

Virtual hosts enable you to isolate, and independently manage, multiple sets of resources on the same physical machine. Determine whether we need a virtual host alias for each port associated with an HTTP transport channel or an HTTP transport. There must be a virtual host alias corresponding to each port used by an HTTP transport channel or an HTTP transport. There is one HTTP transport channel or HTTP transport associated with each Web container, and there is one Web container in each appserver.

By creating a virtual host, a default set of 90 MIME entries is created for the virtual host. You must create a virtual host for each HTTP port in the following cases:

• You use the internal HTTP transport with a port other than the default value of 9082, or for some reason the virtual host does not contain the usual entry for port 9082.

• You create multiple appservers, such as stand-alone servers, managed servers, or cluster members, that are using the same virtual host. Because each server must be listening on a different HTTP port, we need a virtual host alias for the HTTP port of each server.

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Subtopics

Virtual host settings
Host alias collection
MIME type collection

 

Related tasks

Set virtual hosts