2.4.x/docs/manual/vhosts/examples.xml - httpd - Git at Google

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 <manualpage metafile="examples.xml.meta">
 <parentdocument href="./">Virtual Hosts</parentdocument>
     <title>VirtualHost Examples</title>

 <summary>

     <p>This document attempts to answer the commonly-asked questions about
     setting up <a href="index.html">virtual hosts</a>. These scenarios are those involving multiple
     web sites running on a single server, via <a
     href="name-based.html">name-based</a> or <a
     href="ip-based.html">IP-based</a> virtual hosts.
     </p>

 </summary>

   <section id="purename"><title>Running several name-based web
     sites on a single IP address.</title>

     <p>Your server has multiple hostnames that resolve to a single address,
     and you want to respond differently for <code>www.example.com</code>
     and <code>www.example.org</code>.</p>

     <note><title>Note</title><p>Creating virtual
           host configurations on your Apache server does not magically
           cause DNS entries to be created for those host names. You
           <em>must</em> have the names in DNS, resolving to your IP
           address, or nobody else will be able to see your web site. You
           can put entries in your <code>hosts</code> file for local
           testing, but that will work only from the machine with those
           <code>hosts</code> entries.</p>
     </note>

     <highlight language="config">
 # Ensure that Apache listens on port 80
 Listen 80
 &lt;VirtualHost *:80&gt;
     DocumentRoot "/www/example1"
     ServerName www.example.com

     # Other directives here
 &lt;/VirtualHost&gt;

 &lt;VirtualHost *:80&gt;
     DocumentRoot "/www/example2"
     ServerName www.example.org

     # Other directives here
 &lt;/VirtualHost&gt;
     </highlight>

     <p>The asterisks match all addresses, so the main server serves no
     requests. Due to the fact that the virtual host with
     <code>ServerName www.example.com</code> is first
     in the configuration file, it has the highest priority and can be seen
     as the <cite>default</cite> or <cite>primary</cite> server. That means
     that if a request is received that does not match one of the specified
     <directive module="core">ServerName</directive> directives, it will be served by this first
     <directive type="section" module="core">VirtualHost</directive>.</p>

     <p>The above configuration is what you will want to use in almost
     all name-based virtual hosting situations. The only thing that this
     configuration will not work for, in fact, is when you are serving
     different content based on differing IP addresses or ports.</p>

     <note>
             <title>Note</title>

            <p>You may replace <code>*</code> with a specific IP address
            on the system.  Such virtual hosts will only be used for
            HTTP requests received on connection to the specified IP
            address.</p>

            <p>However, it is additionally useful to use <code>*</code>
            on systems where the IP address is not predictable - for
            example if you have a dynamic IP address with your ISP, and
            you are using some variety of dynamic DNS solution. Since
            <code>*</code> matches any IP address, this configuration
            would work without changes whenever your IP address
            changes.</p>
     </note>
   </section>

   <section id="twoips"><title>Name-based hosts on more than one
     IP address.</title>

     <note>
       <title>Note</title>
       <p>Any of the techniques discussed here can be extended to any
       number of IP addresses.</p>
     </note>

     <p>The server has two IP addresses. On one (<code>172.20.30.40</code>), we
     will serve the "main" server, <code>server.example.com</code> and on the
     other (<code>172.20.30.50</code>), we will serve two or more virtual hosts.</p>

     <highlight language="config">
 Listen 80

 # This is the "main" server running on 172.20.30.40
 ServerName server.example.com
 DocumentRoot "/www/mainserver"

 &lt;VirtualHost 172.20.30.50&gt;
     DocumentRoot "/www/example1"
     ServerName www.example.com

     # Other directives here ...
 &lt;/VirtualHost&gt;

 &lt;VirtualHost 172.20.30.50&gt;
     DocumentRoot "/www/example2"
     ServerName www.example.org

     # Other directives here ...
 &lt;/VirtualHost&gt;
     </highlight>

     <p>Any request to an address other than <code>172.20.30.50</code> will be
     served from the main server. A request to <code>172.20.30.50</code> with an
     unknown hostname, or no <code>Host:</code> header, will be served from
     <code>www.example.com</code>.</p>

   </section>

   <section id="intraextra"><title>Serving the same content on
     different IP addresses (such as an internal and external
     address).</title>

     <p>The server machine has two IP addresses (<code>192.168.1.1</code>
     and <code>172.20.30.40</code>). The machine is sitting between an
     internal (intranet) network and an external (internet) network. Outside
     of the network, the name <code>server.example.com</code> resolves to
     the external address (<code>172.20.30.40</code>), but inside the
     network, that same name resolves to the internal address
     (<code>192.168.1.1</code>).</p>

     <p>The server can be made to respond to internal and external requests
     with the same content, with just one <directive type="section" module="core"
     >VirtualHost</directive> section.</p>

     <highlight language="config">
 &lt;VirtualHost 192.168.1.1 172.20.30.40&gt;
     DocumentRoot "/www/server1"
     ServerName server.example.com
     ServerAlias server
 &lt;/VirtualHost&gt;
     </highlight>

     <p>Now requests from both networks will be served from the same
     <directive type="section" module="core">VirtualHost</directive>.</p>

     <note>
           <title>Note:</title><p>On the internal
           network, one can just use the name <code>server</code> rather
           than the fully qualified host name
           <code>server.example.com</code>.</p>

           <p>Note also that, in the above example, you can replace the list
           of IP addresses with <code>*</code>, which will cause the server to
           respond the same on all addresses.</p>
     </note>

   </section>

   <section id="port"><title>Running different sites on different
     ports.</title>

     <p>You have multiple domains going to the same IP and also want to
     serve multiple ports.  The example below illustrates that the name-matching
     takes place after the best matching IP address and port combination
     is determined.</p>

     <highlight language="config">
 Listen 80
 Listen 8080

 &lt;VirtualHost 172.20.30.40:80&gt;
     ServerName www.example.com
     DocumentRoot "/www/domain-80"
 &lt;/VirtualHost&gt;

 &lt;VirtualHost 172.20.30.40:8080&gt;
     ServerName www.example.com
     DocumentRoot "/www/domain-8080"
 &lt;/VirtualHost&gt;

 &lt;VirtualHost 172.20.30.40:80&gt;
     ServerName www.example.org
     DocumentRoot "/www/otherdomain-80"
 &lt;/VirtualHost&gt;

 &lt;VirtualHost 172.20.30.40:8080&gt;
     ServerName www.example.org
     DocumentRoot "/www/otherdomain-8080"
 &lt;/VirtualHost&gt;
     </highlight>

   </section>

   <section id="ip"><title>IP-based virtual hosting</title>

     <p>The server has two IP addresses (<code>172.20.30.40</code> and
     <code>172.20.30.50</code>) which resolve to the names
     <code>www.example.com</code> and <code>www.example.org</code>
     respectively.</p>

     <highlight language="config">
 Listen 80

 &lt;VirtualHost 172.20.30.40&gt;
     DocumentRoot "/www/example1"
     ServerName www.example.com
 &lt;/VirtualHost&gt;

 &lt;VirtualHost 172.20.30.50&gt;
     DocumentRoot "/www/example2"
     ServerName www.example.org
 &lt;/VirtualHost&gt;
     </highlight>

     <p>Requests for any address not specified in one of the
     <code>&lt;VirtualHost&gt;</code> directives (such as
     <code>localhost</code>, for example) will go to the main server, if
     there is one.</p>

   </section>

   <section id="ipport"><title>Mixed port-based and ip-based virtual
   hosts</title>

     <p>The server machine has two IP addresses (<code>172.20.30.40</code> and
     <code>172.20.30.50</code>) which resolve to the names
     <code>www.example.com</code> and <code>www.example.org</code>
     respectively. In each case, we want to run hosts on ports 80 and
     8080.</p>

     <highlight language="config">
 Listen 172.20.30.40:80
 Listen 172.20.30.40:8080
 Listen 172.20.30.50:80
 Listen 172.20.30.50:8080

 &lt;VirtualHost 172.20.30.40:80&gt;
     DocumentRoot "/www/example1-80"
     ServerName www.example.com
 &lt;/VirtualHost&gt;

 &lt;VirtualHost 172.20.30.40:8080&gt;
     DocumentRoot "/www/example1-8080"
     ServerName www.example.com
 &lt;/VirtualHost&gt;

 &lt;VirtualHost 172.20.30.50:80&gt;
     DocumentRoot "/www/example2-80"
     ServerName www.example.org
 &lt;/VirtualHost&gt;

 &lt;VirtualHost 172.20.30.50:8080&gt;
     DocumentRoot "/www/example2-8080"
     ServerName www.example.org
 &lt;/VirtualHost&gt;
     </highlight>

   </section>

   <section id="mixed"><title>Mixed name-based and IP-based
     vhosts</title>

     <p>Any address mentioned in the argument to a virtualhost that never
     appears in another virtual host is a strictly IP-based virtual host.</p>

     <highlight language="config">
 Listen 80
 &lt;VirtualHost 172.20.30.40&gt;
     DocumentRoot "/www/example1"
     ServerName www.example.com
 &lt;/VirtualHost&gt;

 &lt;VirtualHost 172.20.30.40&gt;
     DocumentRoot "/www/example2"
     ServerName www.example.org
 &lt;/VirtualHost&gt;

 &lt;VirtualHost 172.20.30.40&gt;
     DocumentRoot "/www/example3"
     ServerName www.example.net
 &lt;/VirtualHost&gt;

 # IP-based
 &lt;VirtualHost 172.20.30.50&gt;
     DocumentRoot "/www/example4"
     ServerName www.example.edu
 &lt;/VirtualHost&gt;

 &lt;VirtualHost 172.20.30.60&gt;
     DocumentRoot "/www/example5"
     ServerName www.example.gov
 &lt;/VirtualHost&gt;
     </highlight>

   </section>

     <section id="proxy"><title>Using <code>Virtual_host</code> and
     mod_proxy together</title>

     <p>The following example allows a front-end machine to proxy a
     virtual host through to a server running on another machine. In the
     example, a virtual host of the same name is configured on a machine
     at <code>192.168.111.2</code>. The <directive
     module="mod_proxy" name="ProxyPreserveHost">ProxyPreserveHost
     On</directive> directive is used so that the desired hostname is
     passed through, in case we are proxying multiple hostnames to a
     single machine.</p>

     <highlight language="config">
 &lt;VirtualHost *:*&gt;
     ProxyPreserveHost On
     ProxyPass        "/" "http://192.168.111.2/"
     ProxyPassReverse "/" "http://192.168.111.2/"
     ServerName hostname.example.com
 &lt;/VirtualHost&gt;
     </highlight>

     </section>

   <section id="default"><title>Using <code>_default_</code>
     vhosts</title>

     <section id="defaultallports"><title><code>_default_</code> vhosts
     for all ports</title>

     <p>Catching <em>every</em> request to any unspecified IP address and
     port, <em>i.e.</em>, an address/port combination that is not used for
     any other virtual host.</p>

     <highlight language="config">
 &lt;VirtualHost _default_:*&gt;
     DocumentRoot "/www/default"
 &lt;/VirtualHost&gt;
     </highlight>

     <p>Using such a default vhost with a wildcard port effectively prevents
     any request going to the main server.</p>

     <p>A default vhost never serves a request that was sent to an
     address/port that is used for name-based vhosts. If the request
     contained an unknown or no <code>Host:</code> header it is always
     served from the primary name-based vhost (the vhost for that
     address/port appearing first in the configuration file).</p>

     <p>You can use <directive module="mod_alias">AliasMatch</directive> or
     <directive module="mod_rewrite">RewriteRule</directive> to rewrite any
     request to a single information page (or script).</p>
     </section>

     <section id="defaultdifferentports"><title><code>_default_</code> vhosts
     for different ports</title>

     <p>Same as setup 1, but the server listens on several ports and we want
     to use a second <code>_default_</code> vhost for port 80.</p>

     <highlight language="config">
 &lt;VirtualHost _default_:80&gt;
     DocumentRoot "/www/default80"
     # ...
 &lt;/VirtualHost&gt;

 &lt;VirtualHost _default_:*&gt;
     DocumentRoot "/www/default"
     # ...
 &lt;/VirtualHost&gt;
     </highlight>

     <p>The default vhost for port 80 (which <em>must</em> appear before any
     default vhost with a wildcard port) catches all requests that were sent
     to an unspecified IP address. The main server is never used to serve a
     request.</p>
     </section>

     <section id="defaultoneport"><title><code>_default_</code> vhosts
     for one port</title>

     <p>We want to have a default vhost for port 80, but no other default
     vhosts.</p>

     <highlight language="config">
 &lt;VirtualHost _default_:80&gt;
     DocumentRoot "/www/default"
 ...
 &lt;/VirtualHost&gt;
     </highlight>

     <p>A request to an unspecified address on port 80 is served from the
     default vhost. Any other request to an unspecified address and port is
     served from the main server.</p>

     <p>Any use of <code>*</code> in a virtual host declaration will have
     higher precedence than <code>_default_</code>.</p>

     </section>

   </section>

   <section id="migrate"><title>Migrating a name-based vhost to an
     IP-based vhost</title>

     <p>The name-based vhost with the hostname
     <code>www.example.org</code> (from our <a
     href="#name">name-based</a> example, setup 2) should get its own IP
     address. To avoid problems with name servers or proxies who cached the
     old IP address for the name-based vhost we want to provide both
     variants during a migration phase.</p>

     <p>
      The solution is easy, because we can simply add the new IP address
     (<code>172.20.30.50</code>) to the <code>VirtualHost</code>
     directive.</p>

     <highlight language="config">
 Listen 80
 ServerName www.example.com
 DocumentRoot "/www/example1"

 &lt;VirtualHost 172.20.30.40 172.20.30.50&gt;
     DocumentRoot "/www/example2"
     ServerName www.example.org
     # ...
 &lt;/VirtualHost&gt;

 &lt;VirtualHost 172.20.30.40&gt;
     DocumentRoot "/www/example3"
     ServerName www.example.net
     ServerAlias *.example.net
     # ...
 &lt;/VirtualHost&gt;
     </highlight>

     <p>The vhost can now be accessed through the new address (as an
     IP-based vhost) and through the old address (as a name-based
     vhost).</p>

   </section>

   <section id="serverpath"><title>Using the <code>ServerPath</code>
   directive</title>

     <p>We have a server with two name-based vhosts. In order to match the
     correct virtual host a client must send the correct <code>Host:</code>
     header. Old HTTP/1.0 clients do not send such a header and Apache has
     no clue what vhost the client tried to reach (and serves the request
     from the primary vhost). To provide as much backward compatibility as
     possible we create a primary vhost which returns a single page
     containing links with an URL prefix to the name-based virtual
     hosts.</p>

     <highlight language="config">
 &lt;VirtualHost 172.20.30.40&gt;
     # primary vhost
     DocumentRoot "/www/subdomain"
     RewriteEngine On
     RewriteRule "." "/www/subdomain/index.html"
     # ...
 &lt;/VirtualHost&gt;

 &lt;VirtualHost 172.20.30.40&gt;
     DocumentRoot "/www/subdomain/sub1"
     ServerName www.sub1.domain.tld
     ServerPath "/sub1/"
     RewriteEngine On
     RewriteRule "^(/sub1/.*)" "/www/subdomain$1"
     # ...
 &lt;/VirtualHost&gt;

 &lt;VirtualHost 172.20.30.40&gt;
     DocumentRoot "/www/subdomain/sub2"
     ServerName www.sub2.domain.tld
     ServerPath "/sub2/"
     RewriteEngine On
     RewriteRule "^(/sub2/.*)" "/www/subdomain$1"
     # ...
 &lt;/VirtualHost&gt;
     </highlight>

     <p>Due to the <directive module="core">ServerPath</directive>
     directive a request to the URL
     <code>http://www.sub1.domain.tld/sub1/</code> is <em>always</em> served
     from the sub1-vhost.<br /> A request to the URL
     <code>http://www.sub1.domain.tld/</code> is only
     served from the sub1-vhost if the client sent a correct
     <code>Host:</code> header. If no <code>Host:</code> header is sent the
     client gets the information page from the primary host.</p>

     <p>Please note that there is one oddity: A request to
     <code>http://www.sub2.domain.tld/sub1/</code> is also served from the
     sub1-vhost if the client sent no <code>Host:</code> header.</p>

     <p>The <directive module="mod_rewrite">RewriteRule</directive> directives
     are used to make sure that a client which sent a correct
     <code>Host:</code> header can use both URL variants, <em>i.e.</em>,
     with or without URL prefix.</p>

   </section>

 </manualpage>
	<?xml version='1.0' encoding='UTF-8' ?>
	<!DOCTYPE manualpage SYSTEM "../style/manualpage.dtd">
	<?xml-stylesheet type="text/xsl" href="../style/manual.en.xsl"?>
	<!-- $LastChangedRevision$ -->

	<!--
	Licensed to the Apache Software Foundation (ASF) under one or more
	contributor license agreements. See the NOTICE file distributed with
	this work for additional information regarding copyright ownership.
	The ASF licenses this file to You under the Apache License, Version 2.0
	(the "License"); you may not use this file except in compliance with
	the License. You may obtain a copy of the License at

	http://www.apache.org/licenses/LICENSE-2.0

	Unless required by applicable law or agreed to in writing, software
	distributed under the License is distributed on an "AS IS" BASIS,
	WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
	See the License for the specific language governing permissions and
	limitations under the License.
	-->

	<manualpage metafile="examples.xml.meta">
	<parentdocument href="./">Virtual Hosts</parentdocument>
	<title>VirtualHost Examples</title>

	<summary>

	<p>This document attempts to answer the commonly-asked questions about
	setting up <a href="index.html">virtual hosts</a>. These scenarios are those involving multiple
	web sites running on a single server, via <a
	href="name-based.html">name-based</a> or <a
	href="ip-based.html">IP-based</a> virtual hosts.
	</p>

	</summary>

	<section id="purename"><title>Running several name-based web
	sites on a single IP address.</title>

	<p>Your server has multiple hostnames that resolve to a single address,
	and you want to respond differently for <code>www.example.com</code>
	and <code>www.example.org</code>.</p>

	<note><title>Note</title><p>Creating virtual
	host configurations on your Apache server does not magically
	cause DNS entries to be created for those host names. You
	<em>must</em> have the names in DNS, resolving to your IP
	address, or nobody else will be able to see your web site. You
	can put entries in your <code>hosts</code> file for local
	testing, but that will work only from the machine with those
	<code>hosts</code> entries.</p>
	</note>

	<highlight language="config">
	# Ensure that Apache listens on port 80
	Listen 80
	<VirtualHost *:80>
	DocumentRoot "/www/example1"
	ServerName www.example.com

	# Other directives here
	</VirtualHost>

	<VirtualHost *:80>
	DocumentRoot "/www/example2"
	ServerName www.example.org

	# Other directives here
	</VirtualHost>
	</highlight>

	<p>The asterisks match all addresses, so the main server serves no
	requests. Due to the fact that the virtual host with
	<code>ServerName www.example.com</code> is first
	in the configuration file, it has the highest priority and can be seen
	as the <cite>default</cite> or <cite>primary</cite> server. That means
	that if a request is received that does not match one of the specified
	<directive module="core">ServerName</directive> directives, it will be served by this first
	<directive type="section" module="core">VirtualHost</directive>.</p>

	<p>The above configuration is what you will want to use in almost
	all name-based virtual hosting situations. The only thing that this
	configuration will not work for, in fact, is when you are serving
	different content based on differing IP addresses or ports.</p>

	<note>
	<title>Note</title>

	<p>You may replace <code>*</code> with a specific IP address
	on the system. Such virtual hosts will only be used for
	HTTP requests received on connection to the specified IP
	address.</p>

	<p>However, it is additionally useful to use <code>*</code>
	on systems where the IP address is not predictable - for
	example if you have a dynamic IP address with your ISP, and
	you are using some variety of dynamic DNS solution. Since
	<code>*</code> matches any IP address, this configuration
	would work without changes whenever your IP address
	changes.</p>
	</note>
	</section>

	<section id="twoips"><title>Name-based hosts on more than one
	IP address.</title>

	<note>
	<title>Note</title>
	<p>Any of the techniques discussed here can be extended to any
	number of IP addresses.</p>
	</note>

	<p>The server has two IP addresses. On one (<code>172.20.30.40</code>), we
	will serve the "main" server, <code>server.example.com</code> and on the
	other (<code>172.20.30.50</code>), we will serve two or more virtual hosts.</p>

	<highlight language="config">
	Listen 80

	# This is the "main" server running on 172.20.30.40
	ServerName server.example.com
	DocumentRoot "/www/mainserver"

	<VirtualHost 172.20.30.50>
	DocumentRoot "/www/example1"
	ServerName www.example.com

	# Other directives here ...
	</VirtualHost>

	<VirtualHost 172.20.30.50>
	DocumentRoot "/www/example2"
	ServerName www.example.org

	# Other directives here ...
	</VirtualHost>
	</highlight>

	<p>Any request to an address other than <code>172.20.30.50</code> will be
	served from the main server. A request to <code>172.20.30.50</code> with an
	unknown hostname, or no <code>Host:</code> header, will be served from
	<code>www.example.com</code>.</p>

	</section>

	<section id="intraextra"><title>Serving the same content on
	different IP addresses (such as an internal and external
	address).</title>

	<p>The server machine has two IP addresses (<code>192.168.1.1</code>
	and <code>172.20.30.40</code>). The machine is sitting between an
	internal (intranet) network and an external (internet) network. Outside
	of the network, the name <code>server.example.com</code> resolves to
	the external address (<code>172.20.30.40</code>), but inside the
	network, that same name resolves to the internal address
	(<code>192.168.1.1</code>).</p>

	<p>The server can be made to respond to internal and external requests
	with the same content, with just one <directive type="section" module="core"
	>VirtualHost</directive> section.</p>

	<highlight language="config">
	<VirtualHost 192.168.1.1 172.20.30.40>
	DocumentRoot "/www/server1"
	ServerName server.example.com
	ServerAlias server
	</VirtualHost>
	</highlight>

	<p>Now requests from both networks will be served from the same
	<directive type="section" module="core">VirtualHost</directive>.</p>

	<note>
	<title>Note:</title><p>On the internal
	network, one can just use the name <code>server</code> rather
	than the fully qualified host name
	<code>server.example.com</code>.</p>

	<p>Note also that, in the above example, you can replace the list
	of IP addresses with <code>*</code>, which will cause the server to
	respond the same on all addresses.</p>
	</note>

	</section>

	<section id="port"><title>Running different sites on different
	ports.</title>

	<p>You have multiple domains going to the same IP and also want to
	serve multiple ports. The example below illustrates that the name-matching
	takes place after the best matching IP address and port combination
	is determined.</p>

	<highlight language="config">
	Listen 80
	Listen 8080

	<VirtualHost 172.20.30.40:80>
	ServerName www.example.com
	DocumentRoot "/www/domain-80"
	</VirtualHost>

	<VirtualHost 172.20.30.40:8080>
	ServerName www.example.com
	DocumentRoot "/www/domain-8080"
	</VirtualHost>

	<VirtualHost 172.20.30.40:80>
	ServerName www.example.org
	DocumentRoot "/www/otherdomain-80"
	</VirtualHost>

	<VirtualHost 172.20.30.40:8080>
	ServerName www.example.org
	DocumentRoot "/www/otherdomain-8080"
	</VirtualHost>
	</highlight>

	</section>

	<section id="ip"><title>IP-based virtual hosting</title>

	<p>The server has two IP addresses (<code>172.20.30.40</code> and
	<code>172.20.30.50</code>) which resolve to the names
	<code>www.example.com</code> and <code>www.example.org</code>
	respectively.</p>

	<highlight language="config">
	Listen 80

	<VirtualHost 172.20.30.40>
	DocumentRoot "/www/example1"
	ServerName www.example.com
	</VirtualHost>

	<VirtualHost 172.20.30.50>
	DocumentRoot "/www/example2"
	ServerName www.example.org
	</VirtualHost>
	</highlight>

	<p>Requests for any address not specified in one of the
	<code><VirtualHost></code> directives (such as
	<code>localhost</code>, for example) will go to the main server, if
	there is one.</p>

	</section>

	<section id="ipport"><title>Mixed port-based and ip-based virtual
	hosts</title>

	<p>The server machine has two IP addresses (<code>172.20.30.40</code> and
	<code>172.20.30.50</code>) which resolve to the names
	<code>www.example.com</code> and <code>www.example.org</code>
	respectively. In each case, we want to run hosts on ports 80 and
	8080.</p>

	<highlight language="config">
	Listen 172.20.30.40:80
	Listen 172.20.30.40:8080
	Listen 172.20.30.50:80
	Listen 172.20.30.50:8080

	<VirtualHost 172.20.30.40:80>
	DocumentRoot "/www/example1-80"
	ServerName www.example.com
	</VirtualHost>

	<VirtualHost 172.20.30.40:8080>
	DocumentRoot "/www/example1-8080"
	ServerName www.example.com
	</VirtualHost>

	<VirtualHost 172.20.30.50:80>
	DocumentRoot "/www/example2-80"
	ServerName www.example.org
	</VirtualHost>

	<VirtualHost 172.20.30.50:8080>
	DocumentRoot "/www/example2-8080"
	ServerName www.example.org
	</VirtualHost>
	</highlight>

	</section>

	<section id="mixed"><title>Mixed name-based and IP-based
	vhosts</title>

	<p>Any address mentioned in the argument to a virtualhost that never
	appears in another virtual host is a strictly IP-based virtual host.</p>

	<highlight language="config">
	Listen 80
	<VirtualHost 172.20.30.40>
	DocumentRoot "/www/example1"
	ServerName www.example.com
	</VirtualHost>

	<VirtualHost 172.20.30.40>
	DocumentRoot "/www/example2"
	ServerName www.example.org
	</VirtualHost>

	<VirtualHost 172.20.30.40>
	DocumentRoot "/www/example3"
	ServerName www.example.net
	</VirtualHost>

	# IP-based
	<VirtualHost 172.20.30.50>
	DocumentRoot "/www/example4"
	ServerName www.example.edu
	</VirtualHost>

	<VirtualHost 172.20.30.60>
	DocumentRoot "/www/example5"
	ServerName www.example.gov
	</VirtualHost>
	</highlight>

	</section>

	<section id="proxy"><title>Using <code>Virtual_host</code> and
	mod_proxy together</title>

	<p>The following example allows a front-end machine to proxy a
	virtual host through to a server running on another machine. In the
	example, a virtual host of the same name is configured on a machine
	at <code>192.168.111.2</code>. The <directive
	module="mod_proxy" name="ProxyPreserveHost">ProxyPreserveHost
	On</directive> directive is used so that the desired hostname is
	passed through, in case we are proxying multiple hostnames to a
	single machine.</p>

	<highlight language="config">
	<VirtualHost :>
	ProxyPreserveHost On
	ProxyPass "/" "http://192.168.111.2/"
	ProxyPassReverse "/" "http://192.168.111.2/"
	ServerName hostname.example.com
	</VirtualHost>
	</highlight>

	</section>

	<section id="default"><title>Using <code>_default_</code>
	vhosts</title>

	<section id="defaultallports"><title><code>_default_</code> vhosts
	for all ports</title>

	<p>Catching <em>every</em> request to any unspecified IP address and
	port, <em>i.e.</em>, an address/port combination that is not used for
	any other virtual host.</p>

	<highlight language="config">
	<VirtualHost _default_:*>
	DocumentRoot "/www/default"
	</VirtualHost>
	</highlight>

	<p>Using such a default vhost with a wildcard port effectively prevents
	any request going to the main server.</p>

	<p>A default vhost never serves a request that was sent to an
	address/port that is used for name-based vhosts. If the request
	contained an unknown or no <code>Host:</code> header it is always
	served from the primary name-based vhost (the vhost for that
	address/port appearing first in the configuration file).</p>

	<p>You can use <directive module="mod_alias">AliasMatch</directive> or
	<directive module="mod_rewrite">RewriteRule</directive> to rewrite any
	request to a single information page (or script).</p>
	</section>

	<section id="defaultdifferentports"><title><code>_default_</code> vhosts
	for different ports</title>

	<p>Same as setup 1, but the server listens on several ports and we want
	to use a second <code>_default_</code> vhost for port 80.</p>

	<highlight language="config">
	<VirtualHost _default_:80>
	DocumentRoot "/www/default80"
	# ...
	</VirtualHost>

	<VirtualHost _default_:*>
	DocumentRoot "/www/default"
	# ...
	</VirtualHost>
	</highlight>

	<p>The default vhost for port 80 (which <em>must</em> appear before any
	default vhost with a wildcard port) catches all requests that were sent
	to an unspecified IP address. The main server is never used to serve a
	request.</p>
	</section>

	<section id="defaultoneport"><title><code>_default_</code> vhosts
	for one port</title>

	<p>We want to have a default vhost for port 80, but no other default
	vhosts.</p>

	<highlight language="config">
	<VirtualHost _default_:80>
	DocumentRoot "/www/default"
	...
	</VirtualHost>
	</highlight>

	<p>A request to an unspecified address on port 80 is served from the
	default vhost. Any other request to an unspecified address and port is
	served from the main server.</p>

	<p>Any use of <code>*</code> in a virtual host declaration will have
	higher precedence than <code>_default_</code>.</p>

	</section>

	</section>

	<section id="migrate"><title>Migrating a name-based vhost to an
	IP-based vhost</title>

	<p>The name-based vhost with the hostname
	<code>www.example.org</code> (from our <a
	href="#name">name-based</a> example, setup 2) should get its own IP
	address. To avoid problems with name servers or proxies who cached the
	old IP address for the name-based vhost we want to provide both
	variants during a migration phase.</p>

	<p>
	The solution is easy, because we can simply add the new IP address
	(<code>172.20.30.50</code>) to the <code>VirtualHost</code>
	directive.</p>

	<highlight language="config">
	Listen 80
	ServerName www.example.com
	DocumentRoot "/www/example1"

	<VirtualHost 172.20.30.40 172.20.30.50>
	DocumentRoot "/www/example2"
	ServerName www.example.org
	# ...
	</VirtualHost>

	<VirtualHost 172.20.30.40>
	DocumentRoot "/www/example3"
	ServerName www.example.net
	ServerAlias *.example.net
	# ...
	</VirtualHost>
	</highlight>

	<p>The vhost can now be accessed through the new address (as an
	IP-based vhost) and through the old address (as a name-based
	vhost).</p>

	</section>

	<section id="serverpath"><title>Using the <code>ServerPath</code>
	directive</title>

	<p>We have a server with two name-based vhosts. In order to match the
	correct virtual host a client must send the correct <code>Host:</code>
	header. Old HTTP/1.0 clients do not send such a header and Apache has
	no clue what vhost the client tried to reach (and serves the request
	from the primary vhost). To provide as much backward compatibility as
	possible we create a primary vhost which returns a single page
	containing links with an URL prefix to the name-based virtual
	hosts.</p>

	<highlight language="config">
	<VirtualHost 172.20.30.40>
	# primary vhost
	DocumentRoot "/www/subdomain"
	RewriteEngine On
	RewriteRule "." "/www/subdomain/index.html"
	# ...
	</VirtualHost>

	<VirtualHost 172.20.30.40>
	DocumentRoot "/www/subdomain/sub1"
	ServerName www.sub1.domain.tld
	ServerPath "/sub1/"
	RewriteEngine On
	RewriteRule "^(/sub1/.*)" "/www/subdomain$1"
	# ...
	</VirtualHost>

	<VirtualHost 172.20.30.40>
	DocumentRoot "/www/subdomain/sub2"
	ServerName www.sub2.domain.tld
	ServerPath "/sub2/"
	RewriteEngine On
	RewriteRule "^(/sub2/.*)" "/www/subdomain$1"
	# ...
	</VirtualHost>
	</highlight>

	<p>Due to the <directive module="core">ServerPath</directive>
	directive a request to the URL
	<code>http://www.sub1.domain.tld/sub1/</code> is <em>always</em> served
	from the sub1-vhost.<br /> A request to the URL
	<code>http://www.sub1.domain.tld/</code> is only
	served from the sub1-vhost if the client sent a correct
	<code>Host:</code> header. If no <code>Host:</code> header is sent the
	client gets the information page from the primary host.</p>

	<p>Please note that there is one oddity: A request to
	<code>http://www.sub2.domain.tld/sub1/</code> is also served from the
	sub1-vhost if the client sent no <code>Host:</code> header.</p>

	<p>The <directive module="mod_rewrite">RewriteRule</directive> directives
	are used to make sure that a client which sent a correct
	<code>Host:</code> header can use both URL variants, <em>i.e.</em>,
	with or without URL prefix.</p>

	</section>

	</manualpage>