NameVirtualHost tells the Apache Web server on which IP address and, optionally, which port to listen for requests by clients containing the domain name in the HTTP header.

The first argument can be a fully qualified domain name, but it is recommended to use the IP address. The second argument is the port and is optional. By default, port 80 is used and is configured via the Listen directive (Network Device Selection).

The wild card * can be used for both the IP address and the port number to receive requests on all interfaces. IPv6 addresses must be enclosed in square brackets.

# NameVirtualHost IP-address[:Port]
NameVirtualHost 192.168.1.100:80
NameVirtualHost 192.168.1.100
NameVirtualHost *:80
NameVirtualHost *
NameVirtualHost [2002:c0a8:164::]:80
                

The <VirtualHost></VirtualHost> blocks holds the information that applies to a particular domain. When Apache receives a client request for a defined VirtualHost, it uses the directives enclosed in this section. Any Apache directive that is allowed in the VirtualHost context can be used here. The opening VirtualHost tag takes the following arguments in a name-based virtual host configuration:

The wild card * is also allowed as a substitute for the IP address. This syntax is only valid in combination with the wild card usage in NameVirtualHost * . When using IPv6 addresses, the address must be included in square brackets.

<VirtualHost 192.168.1.100:80>
    ServerName www.example.com
    DocumentRoot /srv/www/htdocs/example.com
    ServerAdmin webmaster@example.com
    ErrorLog /var/log/apache2/www.example.com-error_log
    CustomLog /var/log/apache2/www.example.com-access_log common
</VirtualHost>

<VirtualHost 192.168.1.100:80>
    ServerName www.example.net
    DocumentRoot /srv/www/htdocs/example.net
    ServerAdmin webmaster@example.net
    ErrorLog /var/log/apache2/www.example.net-error_log
    CustomLog /var/log/apache2/www.example.net-access_log common
</VirtualHost>

<VirtualHost [2002:c0a8:164::]>
    # 2002:c0a8:164:: is the IPv6 equivalent to 192.168.1.100
    ServerName www.example.org
    DocumentRoot /srv/www/htdocs/example.org
    ServerAdmin webmaster@example.org
    ErrorLog /var/log/apache2/www.example.org-error_log
    CustomLog /var/log/apache2/www.example.org-access_log common
</VirtualHost>
                

In this example, both the domain www.example.com and www.example.net are hosted on the machine with the IP address 192.168.1.100. The first VirtualHost is the default for all incoming requests to the Web server.

The directives ErrorLog (described in Section 46.3.2.3.4, “ErrorLog file | "|command" ”) and CustomLog (see http://httpd.apache.org/docs-2.0/mod/mod_log_config.html#customlog) do not need to contain the domain name. Here, use a name of your choice.

For Apache to host multiple IPs, the physical machine must accept requests for multiple IPs. This is called multi-IP hosting. Additionally, IP aliasing must be activated in the kernel. This is the default setting in SUSE Linux.

Once the kernel has been configured for IP aliasing, the commands ifconfig and route can be used to set up additional IPs on the host. These commands must be executed as root.

For the following example, it is assumed that the host already has the IP 192.168.0.10 assigned for the network device eth0. Enter the command ifconfig to view the IP of the host. Further IP addresses can be added with the following commands:

ip addr add 192.168.0.20/24 dev eth0
ip addr add 192.168.0.30/24 dev eth0
            

All these IP addresses are assigned to the same physical network device (eth0).

Once IP aliasing has been set up on the system (or the host has been equipped with several network cards), Apache can be configured. A separate VirtualHost block is needed for every virtual server.

The following example shows Apache running on a machine with the IP 192.168.1.10, hosting two domains on the additional IPs 192.168.0.20 and 192.168.0.30. This particular example only works on a private network, because IPs ranging from 192.168.0.0 to 192.168.0.255 are not routed to the public Internet.

<VirtualHost 192.168.0.20>
    ServerName www.example.com
    DocumentRoot /srv/www/htdocs/example.com
    ServerAdmin webmaster@example.com
    ErrorLog /var/log/apache2/www.example.com-error_log
    CustomLog /var/log/apache2/www.example.com-access_log common
</VirtualHost>

<VirtualHost 192.168.0.30>
    ServerName www.example.net
    DocumentRoot /srv/www/htdocs/example.net
    ServerAdmin tux@example.net
    ErrorLog /var/log/apache2/www.example.net-error_log
    CustomLog /var/log/apache2/www.example.net-access_log common
</VirtualHost>
                

Here, VirtualHost directives are only specified for interfaces other than 192.168.0.10. When a Listen directive (described in Network Device Selection) is also configured for 192.168.0.10, a separate IP-based virtual host must be created to answer HTTP requests to that interface or the directives found in the Main Server section of /etc/apache2/httpd.conf (see Section 46.3.2.3, “Apache Directives in /etc/apache2/httpd.conf: Main Server ”) are applied.