Virtual servers

Apache has the capability to support multiple sites from the same server instance. This gives great flexibility, and at the same time, ease of management. This flexibility is known as virtual hosting. There are three basic ways of running virtual hosting with Apache:

Name-based	This uses different names for each site and a common IP address, probably the most popular form of virtual hosting
IP-based	This uses a different IP address for each site
Port-based	This uses individual port numbers for each site

We will look at all three of the methods and configurations within the httpd.conf required to implement each method.

Name-based

Name-based virtual hosting has been made possible with the introduction of HTTP protocol version 1.1, also known as HTTP/1.1. When a browser is only capable of HTTP/1.0, a protocol tries to load a web page; it goes through the following steps:

1. Resolves theurbanpinguin.org hostname to an IP address.

2. Connects to the resolved IP address over TCP...