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 <H1 ALIGN="CENTER">Dynamically configured mass virtual hosting</H1>

 <P>This document describes how to efficiently serve an arbitrary number
 of virtual hosts with Apache 1.3. Some familiarity with
 <A HREF="../mod/mod_rewrite.html"><CODE>mod_rewrite</CODE></A> is
 useful.</P>

 <!--

 Written by Tony Finch (fanf@demon.net) (dot@dotat.at).

 Some examples were derived from Ralf S. Engleschall's document
 	http://www.engelschall.com/pw/apache/rewriteguide/

 Some suggestions were made by Brian Behlendorf.

 -->

 <H2><A NAME="contents">Contents:</A></H2>

 <UL>
 <LI><A HREF="#motivation">Motivation</A>
 <LI><A HREF="#overview">Overview of the technique</A>
 <LI><A HREF="#simple">Simple name-based dynamic virtual hosts</A>
 <LI><A HREF="#homepages">A virtually hosted homepages system</A>
 <LI><A HREF="#xtra-conf">Using a separate virtual host configuration file</A>
 <LI><A HREF="#combinations">Using more than one virtual hosting system on the same server</A>
 </UL>

 <HR><H2><A NAME="motivation">Motivation</A></H2>

 <P>The techniques described here are of interest if your
 <CODE>httpd.conf</CODE> contains hundreds of
 <CODE>&lt;VirtualHost&gt;</CODE> sections that are substantially the
 same, for example:
 <PRE>
 NameVirtualHost 111.22.33.44
 &lt;VirtualHost 111.22.33.44&gt;
 	ServerName		           www.customer-1.com
 	DocumentRoot		/www/hosts/www.customer-1.com/docs
 	ScriptAlias  /cgi-bin/  /www/hosts/www.customer-1.com/cgi-bin
 &lt;/VirtualHost&gt;
 &lt;VirtualHost 111.22.33.44&gt;
 	ServerName		           www.customer-2.com
 	DocumentRoot		/www/hosts/www.customer-2.com/docs
 	ScriptAlias  /cgi-bin/  /www/hosts/www.customer-2.com/cgi-bin
 &lt;/VirtualHost&gt;
 # blah blah blah
 &lt;VirtualHost 111.22.33.44&gt;
 	ServerName		           www.customer-N.com
 	DocumentRoot		/www/hosts/www.customer-N.com/docs
 	ScriptAlias  /cgi-bin/  /www/hosts/www.customer-N.com/cgi-bin
 &lt;/VirtualHost&gt;
 </PRE>
 </P>

 <P>The basic idea is to replace all of the static
 <CODE>&lt;VirtualHost&gt;</CODE> configuration with a mechanism that
 works it out dynamically. This has a number of advantages:
 <OL>
     <LI>Your configuration file is smaller so Apache starts faster and
 	uses less memory.
     <LI>Adding virtual hosts is simply a matter of creating the
 	appropriate directories in the filesystem and entries in the DNS -
 	you don't need to reconfigure or restart Apache.
 </OL>
 </P>

 <P>The main disadvantage is that you cannot have a different log file
 for each server; however if you have very many virtual hosts then
 doing this is dubious anyway because it eats file descriptors. It's
 better to log to a pipe or a fifo and arrange for the process at the
 other end to distribute the logs (and perhaps accumulate statistics,
 etc.). A <CODE>LogFormat</CODE> directive that includes
 <CODE>%v</CODE> for the virtual host makes it easy to do this.</P>


 <HR><H2><A NAME="overview">Overview of the technique</A></H2>

 <P>All of the dynamic virtual hosts will either be configured as part
 of the main server configuration, or within a
 <CODE>&lt;VirtualHost&gt;</CODE> section. For a simple (very uniform)
 setup, <CODE>&lt;VirtualHost&gt;</CODE> sections aren't needed at all.</P>

 <P>A couple of things need to be `faked' to make the dynamic virtual
 host look like a normal one. The most important is the server name
 (configured with <CODE>ServerName</CODE> and available to CGIs via the
 <CODE>SERVER_NAME</CODE> environment variable). The way it is
 determined is controlled by the <CODE>UseCanonicalName</CODE>
 directive: with <CODE>UseCanonicalName off</CODE> the server name
 comes from the contents of the <CODE>Host:</CODE> header in the
 request. If there is no <CODE>Host:</CODE> header then the value
 configured with <CODE>ServerName</CODE> is used instead.</P>

 <P>The other one is the document root (configured with
 <CODE>DocumentRoot</CODE> and available to CGIs via the
 <CODE>DOCUMENT_ROOT</CODE> environment variable). This is used by the
 core module when mapping URIs to filenames, but in the context of
 dynamic virtual hosting its value only matters if any CGIs or SSI
 documents make use of the <CODE>DOCUMENT_ROOT</CODE> environment
 variable. This is an Apache extension to the CGI specification and as
 such shouldn't really be relied upon, especially because this
 technique breaks it: there isn't currently a way of setting
 <CODE>DOCUMENT_ROOT</CODE> dynamically.</P>

 <P>The meat of the mechanism works via Apache's URI-to-filename
 translation API phase. This is used by a number of modules:
 <A HREF="../mod/mod_rewrite.html"><CODE>mod_rewrite</CODE></A>,
 <A HREF="../mod/mod_alias.html"><CODE>mod_alias</CODE></A>,
 <A HREF="../mod/mod_userdir.html"><CODE>mod_userdir</CODE></A>,
 and <A HREF="../mod/core.html">the core module</A>.
 In the default configuration these modules are called in that order
 and given a chance to say that they know what the filename is. Most of
 these modules do it in a fairly simple fashion (e.g. the core module
 concatenates the document root and the URI) except for
 <CODE>mod_rewrite</CODE>, which provides enough functionality to do
 all sorts of sick and twisted things (like dynamic virtual hosting).
 Note that because of the order in which the modules are called, using
 a <CODE>mod_rewrite</CODE> configuration that matches any URI means
 that the other modules (particularly <CODE>mod_alias</CODE>) will
 cease to function. The examples below show how to deal with this.</P>

 <P><STRONG>The dynamic virtual hosting idea is very simple: use the
 server name as well as the URI to determine the corresponding
 filename.</STRONG></P>


 <HR><H2><A NAME="simple">Simple name-based dynamic virtual hosts</A></H2>

 <P>This extract from <CODE>httpd.conf</CODE> implements the virtual
 host arrangement outlined in the <A HREF="#motivation">Motivation</A>
 section above, but in a generic fashion.</P>

 <P>The first half shows some other configuration options that are
 needed to make the <CODE>mod_rewrite</CODE> part work as expected; the
 second half uses <CODE>mod_rewrite</CODE> to do the actual work. Some
 care is taken to do a per-dynamic-virtual-host equivalent of
 <CODE>ScriptAlias</CODE>.</P>

 <PRE>
 # dynamic ServerName
 UseCanonicalName Off

 # splittable logs
 LogFormat "%v %h %l %u %t \"%r\" %s %b" vcommon
 CustomLog logs/access_log vcommon

 &lt;Directory /www/hosts&gt;
 	# ExecCGI is needed here because we can't force
 	# CGI execution in the way that ScriptAlias does
 	Options FollowSymLinks ExecCGI
 &lt;/Directory&gt;

 # now for the hard bit

 RewriteEngine On

 # a ServerName derived from a Host: header may be any case at all
 RewriteMap  lowercase  int:tolower

 ## deal with normal documents first:
 # allow Alias /icons/ to work - repeat for other aliases
 RewriteCond  %{REQUEST_URI}  !^/icons/
 # allow CGIs to work
 RewriteCond  %{REQUEST_URI}  !^/cgi-bin/
 # do the magic
 RewriteRule  ^/(.*)$  /www/hosts/${lowercase:%{SERVER_NAME}}/docs/$1

 ## and now deal with CGIs - we have to force a MIME type
 RewriteCond  %{REQUEST_URI}  ^/cgi-bin/
 RewriteRule  ^/(.*)$  /www/hosts/${lowercase:%{SERVER_NAME}}/cgi-bin/$1  [T=application/x-httpd-cgi]

 # that's it!
 </PRE>


 <HR><H2><A NAME="homepages">A virtually hosted homepages system</A></H2>

 <P>This is an adjustment of the above system tailored for an ISP's
 homepages server. Using slightly more complicated rewriting rules we
 can select substrings of the server name to use in the filename so
 that e.g. the documents for <SAMP>www.user.isp.com</SAMP> are found in
 <CODE>/home/user/</CODE>. It uses a single <CODE>cgi-bin</CODE>
 directory instead of one per virtual host.</P>

 <PRE>
 RewriteEngine on

 RewriteMap   lowercase  int:tolower

 # allow CGIs to work
 RewriteCond  %{REQUEST_URI}  !^/cgi-bin/

 # check the hostname is right so that the RewriteRule works
 RewriteCond  ${lowercase:%{HTTP_HOST}}  ^www\.[a-z-]+\.isp\.com$

 # concatenate the virtual host name onto the start of the URI
 # the [C] means do the next rewrite on the result of this one
 RewriteRule  ^(.+)  ${lowercase:%{HTTP_HOST}}$1  [C]

 # now create the real file name
 RewriteRule  ^www\.([a-z-]+)\.isp\.com/(.*) /home/$1/$2

 # define the global CGI directory
 ScriptAlias  /cgi-bin/  /www/std-cgi/
 </PRE>


 <HR><H2><A NAME="xtra-conf">Using a separate virtual host configuration file</A></H2>

 <P>This arrangement uses a separate configuration file to specify the
 translation from virtual host to document root. This provides more
 flexibility but requires more configuration.</P>

 <P>The <CODE>vhost.map</CODE> file contains something like this:
 <PRE>
 www.customer-1.com  /www/customers/1
 www.customer-2.com  /www/customers/2
 # ...
 www.customer-N.com  /www/customers/N
 </PRE>
 </P>

 <P>The <CODE>http.conf</CODE> contains this:
 <PRE>
 RewriteEngine on

 RewriteMap   lowercase  int:tolower

 # define the map file
 RewriteMap   vhost      txt:/www/conf/vhost.map

 # deal with aliases as above
 RewriteCond  %{REQUEST_URI}               !^/icons/
 RewriteCond  %{REQUEST_URI}               !^/cgi-bin/
 RewriteCond  ${lowercase:%{SERVER_NAME}}  ^(.+)$
 # this does the file-based remap
 RewriteCond  ${vhost:%1}                  ^(/.*)$
 RewriteRule  ^/(.*)$                      %1/docs/$1

 RewriteCond  %{REQUEST_URI}               ^/cgi-bin/
 RewriteCond  ${lowercase:%{SERVER_NAME}}  ^(.+)$
 RewriteCond  ${vhost:%1}                  ^(/.*)$
 RewriteRule  ^/(.*)$                      %1/cgi-bin/$1
 </PRE>
 </P>


 <HR><H2><A NAME="combinations">Using more than one virtual hosting system on the same server</A></H2>

 <P>With more complicated setups, you can use Apache's normal
 <CODE>&lt;VirtualHost&gt;</CODE> directives to control the scope of
 the various rewrite configurations. For example, you could have one IP
 address for homepages customers and another for commercial customers
 with the following setup. This can of course be combined with
 convential <CODE>&lt;VirtualHost&gt;</CODE> configuration
 sections.</P>

 <PRE>
 UseCanonicalName Off

 LogFormat "%v %h %l %u %t \"%r\" %s %b" vcommon
 CustomLog logs/access_log vcommon

 &lt;Directory /www/commercial&gt;
 	Options FollowSymLinks ExecCGI
 	AllowOverride All
 &lt;/Directory&gt;

 &lt;Directory /www/homepages&gt;
 	Options FollowSymLinks
 	AllowOverride None
 &lt;/Directory&gt;

 &lt;VirtualHost 111.22.33.44&gt;
 	ServerName www.commercial.isp.com

 	RewriteEngine On
 	RewriteMap    lowercase  int:tolower

 	RewriteCond   %{REQUEST_URI}  !^/icons/
 	RewriteCond   %{REQUEST_URI}  !^/cgi-bin/
 	RewriteRule   ^/(.*)$  /www/commercial/${lowercase:%{SERVER_NAME}}/docs/$1

 	RewriteCond   %{REQUEST_URI}  ^/cgi-bin/
 	RewriteRule   ^/(.*)$  /www/commercial/${lowercase:%{SERVER_NAME}}/cgi-bin/$1  [T=application/x-httpd-cgi]
 &lt;/VirtualHost&gt;

 &lt;VirtualHost 111.22.33.45&gt;
 	ServerName www.homepages.isp.com

 	RewriteEngine on
 	RewriteMap    lowercase  int:tolower

 	RewriteCond   %{REQUEST_URI}  !^/cgi-bin/

 	RewriteCond   ${lowercase:%{HTTP_HOST}}  ^www\.[a-z-]+\.isp\.com$
 	RewriteRule   ^(.+)  ${lowercase:%{HTTP_HOST}}$1  [C]
 	RewriteRule   ^www\.([a-z-]+)\.isp\.com/(.*) /www/homepages/$1/$2

 	ScriptAlias   /cgi-bin/ /www/std-cgi/
 &lt;/VirtualHost&gt;
 </PRE>


 <HR>

 <H3 ALIGN="CENTER">
  Apache HTTP Server Version 1.3
 </H3>

 <A HREF="./"><IMG SRC="../images/index.gif" ALT="Index"></A>
 <A HREF="../"><IMG SRC="../images/home.gif" ALT="Home"></A>

 </BODY>
 </HTML>
	<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 3.2 Final//EN">
	<HTML><HEAD>
	<TITLE>Dynamically configured mass virtual hosting</TITLE>
	</HEAD>

	<!-- Background white, links blue (unvisited), navy (visited), red (active) -->
	<BODY
	BGCOLOR="#FFFFFF"
	TEXT="#000000"
	LINK="#0000FF"
	VLINK="#000080"
	ALINK="#FF0000"
	>
	<!--#include virtual="header.html" -->
	<H1 ALIGN="CENTER">Dynamically configured mass virtual hosting</H1>

	<P>This document describes how to efficiently serve an arbitrary number
	of virtual hosts with Apache 1.3. Some familiarity with
	<A HREF="../mod/mod_rewrite.html"><CODE>mod_rewrite</CODE></A> is
	useful.</P>

	<!--

	Written by Tony Finch (fanf@demon.net) (dot@dotat.at).

	Some examples were derived from Ralf S. Engleschall's document
	http://www.engelschall.com/pw/apache/rewriteguide/

	Some suggestions were made by Brian Behlendorf.

	-->

	<H2><A NAME="contents">Contents:</A></H2>

	<UL>
	<LI><A HREF="#motivation">Motivation</A>
	<LI><A HREF="#overview">Overview of the technique</A>
	<LI><A HREF="#simple">Simple name-based dynamic virtual hosts</A>
	<LI><A HREF="#homepages">A virtually hosted homepages system</A>
	<LI><A HREF="#xtra-conf">Using a separate virtual host configuration file</A>
	<LI><A HREF="#combinations">Using more than one virtual hosting system on the same server</A>
	</UL>

	<HR><H2><A NAME="motivation">Motivation</A></H2>

	<P>The techniques described here are of interest if your
	<CODE>httpd.conf</CODE> contains hundreds of
	<CODE><VirtualHost></CODE> sections that are substantially the
	same, for example:
	<PRE>
	NameVirtualHost 111.22.33.44
	<VirtualHost 111.22.33.44>
	ServerName www.customer-1.com
	DocumentRoot /www/hosts/www.customer-1.com/docs
	ScriptAlias /cgi-bin/ /www/hosts/www.customer-1.com/cgi-bin
	</VirtualHost>
	<VirtualHost 111.22.33.44>
	ServerName www.customer-2.com
	DocumentRoot /www/hosts/www.customer-2.com/docs
	ScriptAlias /cgi-bin/ /www/hosts/www.customer-2.com/cgi-bin
	</VirtualHost>
	# blah blah blah
	<VirtualHost 111.22.33.44>
	ServerName www.customer-N.com
	DocumentRoot /www/hosts/www.customer-N.com/docs
	ScriptAlias /cgi-bin/ /www/hosts/www.customer-N.com/cgi-bin
	</VirtualHost>
	</PRE>
	</P>

	<P>The basic idea is to replace all of the static
	<CODE><VirtualHost></CODE> configuration with a mechanism that
	works it out dynamically. This has a number of advantages:
	<OL>
	<LI>Your configuration file is smaller so Apache starts faster and
	uses less memory.
	<LI>Adding virtual hosts is simply a matter of creating the
	appropriate directories in the filesystem and entries in the DNS -
	you don't need to reconfigure or restart Apache.
	</OL>
	</P>

	<P>The main disadvantage is that you cannot have a different log file
	for each server; however if you have very many virtual hosts then
	doing this is dubious anyway because it eats file descriptors. It's
	better to log to a pipe or a fifo and arrange for the process at the
	other end to distribute the logs (and perhaps accumulate statistics,
	etc.). A <CODE>LogFormat</CODE> directive that includes
	<CODE>%v</CODE> for the virtual host makes it easy to do this.</P>


	<HR><H2><A NAME="overview">Overview of the technique</A></H2>

	<P>All of the dynamic virtual hosts will either be configured as part
	of the main server configuration, or within a
	<CODE><VirtualHost></CODE> section. For a simple (very uniform)
	setup, <CODE><VirtualHost></CODE> sections aren't needed at all.</P>

	<P>A couple of things need to be `faked' to make the dynamic virtual
	host look like a normal one. The most important is the server name
	(configured with <CODE>ServerName</CODE> and available to CGIs via the
	<CODE>SERVER_NAME</CODE> environment variable). The way it is
	determined is controlled by the <CODE>UseCanonicalName</CODE>
	directive: with <CODE>UseCanonicalName off</CODE> the server name
	comes from the contents of the <CODE>Host:</CODE> header in the
	request. If there is no <CODE>Host:</CODE> header then the value
	configured with <CODE>ServerName</CODE> is used instead.</P>

	<P>The other one is the document root (configured with
	<CODE>DocumentRoot</CODE> and available to CGIs via the
	<CODE>DOCUMENT_ROOT</CODE> environment variable). This is used by the
	core module when mapping URIs to filenames, but in the context of
	dynamic virtual hosting its value only matters if any CGIs or SSI
	documents make use of the <CODE>DOCUMENT_ROOT</CODE> environment
	variable. This is an Apache extension to the CGI specification and as
	such shouldn't really be relied upon, especially because this
	technique breaks it: there isn't currently a way of setting
	<CODE>DOCUMENT_ROOT</CODE> dynamically.</P>

	<P>The meat of the mechanism works via Apache's URI-to-filename
	translation API phase. This is used by a number of modules:
	<A HREF="../mod/mod_rewrite.html"><CODE>mod_rewrite</CODE></A>,
	<A HREF="../mod/mod_alias.html"><CODE>mod_alias</CODE></A>,
	<A HREF="../mod/mod_userdir.html"><CODE>mod_userdir</CODE></A>,
	and <A HREF="../mod/core.html">the core module</A>.
	In the default configuration these modules are called in that order
	and given a chance to say that they know what the filename is. Most of
	these modules do it in a fairly simple fashion (e.g. the core module
	concatenates the document root and the URI) except for
	<CODE>mod_rewrite</CODE>, which provides enough functionality to do
	all sorts of sick and twisted things (like dynamic virtual hosting).
	Note that because of the order in which the modules are called, using
	a <CODE>mod_rewrite</CODE> configuration that matches any URI means
	that the other modules (particularly <CODE>mod_alias</CODE>) will
	cease to function. The examples below show how to deal with this.</P>

	<P><STRONG>The dynamic virtual hosting idea is very simple: use the
	server name as well as the URI to determine the corresponding
	filename.</STRONG></P>


	<HR><H2><A NAME="simple">Simple name-based dynamic virtual hosts</A></H2>

	<P>This extract from <CODE>httpd.conf</CODE> implements the virtual
	host arrangement outlined in the <A HREF="#motivation">Motivation</A>
	section above, but in a generic fashion.</P>

	<P>The first half shows some other configuration options that are
	needed to make the <CODE>mod_rewrite</CODE> part work as expected; the
	second half uses <CODE>mod_rewrite</CODE> to do the actual work. Some
	care is taken to do a per-dynamic-virtual-host equivalent of
	<CODE>ScriptAlias</CODE>.</P>

	<PRE>
	# dynamic ServerName
	UseCanonicalName Off

	# splittable logs
	LogFormat "%v %h %l %u %t \"%r\" %s %b" vcommon
	CustomLog logs/access_log vcommon

	<Directory /www/hosts>
	# ExecCGI is needed here because we can't force
	# CGI execution in the way that ScriptAlias does
	Options FollowSymLinks ExecCGI
	</Directory>

	# now for the hard bit

	RewriteEngine On

	# a ServerName derived from a Host: header may be any case at all
	RewriteMap lowercase int:tolower

	## deal with normal documents first:
	# allow Alias /icons/ to work - repeat for other aliases
	RewriteCond %{REQUEST_URI} !^/icons/
	# allow CGIs to work
	RewriteCond %{REQUEST_URI} !^/cgi-bin/
	# do the magic
	RewriteRule ^/(.*)$ /www/hosts/${lowercase:%{SERVER_NAME}}/docs/$1

	## and now deal with CGIs - we have to force a MIME type
	RewriteCond %{REQUEST_URI} ^/cgi-bin/
	RewriteRule ^/(.*)$ /www/hosts/${lowercase:%{SERVER_NAME}}/cgi-bin/$1 [T=application/x-httpd-cgi]

	# that's it!
	</PRE>


	<HR><H2><A NAME="homepages">A virtually hosted homepages system</A></H2>

	<P>This is an adjustment of the above system tailored for an ISP's
	homepages server. Using slightly more complicated rewriting rules we
	can select substrings of the server name to use in the filename so
	that e.g. the documents for <SAMP>www.user.isp.com</SAMP> are found in
	<CODE>/home/user/</CODE>. It uses a single <CODE>cgi-bin</CODE>
	directory instead of one per virtual host.</P>

	<PRE>
	RewriteEngine on

	RewriteMap lowercase int:tolower

	# allow CGIs to work
	RewriteCond %{REQUEST_URI} !^/cgi-bin/

	# check the hostname is right so that the RewriteRule works
	RewriteCond ${lowercase:%{HTTP_HOST}} ^www\.[a-z-]+\.isp\.com$

	# concatenate the virtual host name onto the start of the URI
	# the [C] means do the next rewrite on the result of this one
	RewriteRule ^(.+) ${lowercase:%{HTTP_HOST}}$1 [C]

	# now create the real file name
	RewriteRule ^www\.([a-z-]+)\.isp\.com/(.*) /home/$1/$2

	# define the global CGI directory
	ScriptAlias /cgi-bin/ /www/std-cgi/
	</PRE>


	<HR><H2><A NAME="xtra-conf">Using a separate virtual host configuration file</A></H2>

	<P>This arrangement uses a separate configuration file to specify the
	translation from virtual host to document root. This provides more
	flexibility but requires more configuration.</P>

	<P>The <CODE>vhost.map</CODE> file contains something like this:
	<PRE>
	www.customer-1.com /www/customers/1
	www.customer-2.com /www/customers/2
	# ...
	www.customer-N.com /www/customers/N
	</PRE>
	</P>

	<P>The <CODE>http.conf</CODE> contains this:
	<PRE>
	RewriteEngine on

	RewriteMap lowercase int:tolower

	# define the map file
	RewriteMap vhost txt:/www/conf/vhost.map

	# deal with aliases as above
	RewriteCond %{REQUEST_URI} !^/icons/
	RewriteCond %{REQUEST_URI} !^/cgi-bin/
	RewriteCond ${lowercase:%{SERVER_NAME}} ^(.+)$
	# this does the file-based remap
	RewriteCond ${vhost:%1} ^(/.*)$
	RewriteRule ^/(.*)$ %1/docs/$1

	RewriteCond %{REQUEST_URI} ^/cgi-bin/
	RewriteCond ${lowercase:%{SERVER_NAME}} ^(.+)$
	RewriteCond ${vhost:%1} ^(/.*)$
	RewriteRule ^/(.*)$ %1/cgi-bin/$1
	</PRE>
	</P>


	<HR><H2><A NAME="combinations">Using more than one virtual hosting system on the same server</A></H2>

	<P>With more complicated setups, you can use Apache's normal
	<CODE><VirtualHost></CODE> directives to control the scope of
	the various rewrite configurations. For example, you could have one IP
	address for homepages customers and another for commercial customers
	with the following setup. This can of course be combined with
	convential <CODE><VirtualHost></CODE> configuration
	sections.</P>

	<PRE>
	UseCanonicalName Off

	LogFormat "%v %h %l %u %t \"%r\" %s %b" vcommon
	CustomLog logs/access_log vcommon

	<Directory /www/commercial>
	Options FollowSymLinks ExecCGI
	AllowOverride All
	</Directory>

	<Directory /www/homepages>
	Options FollowSymLinks
	AllowOverride None
	</Directory>

	<VirtualHost 111.22.33.44>
	ServerName www.commercial.isp.com

	RewriteEngine On
	RewriteMap lowercase int:tolower

	RewriteCond %{REQUEST_URI} !^/icons/
	RewriteCond %{REQUEST_URI} !^/cgi-bin/
	RewriteRule ^/(.*)$ /www/commercial/${lowercase:%{SERVER_NAME}}/docs/$1

	RewriteCond %{REQUEST_URI} ^/cgi-bin/
	RewriteRule ^/(.*)$ /www/commercial/${lowercase:%{SERVER_NAME}}/cgi-bin/$1 [T=application/x-httpd-cgi]
	</VirtualHost>

	<VirtualHost 111.22.33.45>
	ServerName www.homepages.isp.com

	RewriteEngine on
	RewriteMap lowercase int:tolower

	RewriteCond %{REQUEST_URI} !^/cgi-bin/

	RewriteCond ${lowercase:%{HTTP_HOST}} ^www\.[a-z-]+\.isp\.com$
	RewriteRule ^(.+) ${lowercase:%{HTTP_HOST}}$1 [C]
	RewriteRule ^www\.([a-z-]+)\.isp\.com/(.*) /www/homepages/$1/$2

	ScriptAlias /cgi-bin/ /www/std-cgi/
	</VirtualHost>
	</PRE>


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	<H3 ALIGN="CENTER">
	Apache HTTP Server Version 1.3
	</H3>

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