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diff --git a/docs/manual/vhosts/mass.html b/docs/manual/vhosts/mass.html deleted file mode 100644 index eb46f3db6f..0000000000 --- a/docs/manual/vhosts/mass.html +++ /dev/null @@ -1,442 +0,0 @@ -<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" - "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd"> - -<html xmlns="http://www.w3.org/1999/xhtml"> - <head> - <meta name="generator" content="HTML Tidy, see www.w3.org" /> - - <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. <!-- - - 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. - - --> - </p> - - <h2><a id="contents" name="contents">Contents:</a></h2> - - <ul> - <li><a href="#motivation">Motivation</a></li> - - <li><a href="#overview">Overview</a></li> - - <li><a href="#simple">Simple dynamic virtual hosts</a></li> - - <li><a href="#homepages">A virtually hosted homepages - system</a></li> - - <li><a href="#combinations">Using more than one virtual - hosting system on the same server</a></li> - - <li><a href="#ipbased">More efficient IP-based virtual - hosting</a></li> - - <li><a href="#oldversion">Using older versions of - Apache</a></li> - - <li><a href="#simple.rewrite">Simple dynamic virtual hosts - using <code>mod_rewrite</code></a></li> - - <li><a href="#homepages.rewrite">A homepages system using - <code>mod_rewrite</code></a></li> - - <li><a href="#xtra-conf">Using a separate virtual host - configuration file</a></li> - </ul> - <hr /> - - <h2><a id="motivation" name="motivation">Motivation</a></h2> - - <p>The techniques described here are of interest if your - <code>httpd.conf</code> contains many - <code><VirtualHost></code> sections that are - substantially the same, for example:</p> -<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> - <br /> - <br /> - - - <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:</p> - - <ol> - <li>Your configuration file is smaller so Apache starts - faster and uses less memory.</li> - - <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.</li> - </ol> - <br /> - <br /> - - - <p>The main disadvantage is that you cannot have a different - log file for each virtual host; however if you have very many - virtual hosts then doing this is dubious anyway because it eats - file descriptors. It is better to log to a pipe or a fifo and - arrange for the process at the other end to distribute the logs - to the customers (it can also accumulate statistics, etc.).</p> - <hr /> - - <h2><a id="overview" name="overview">Overview</a></h2> - - <p>A virtual host is defined by two pieces of information: its - IP address, and the contents of the <code>Host:</code> header - in the HTTP request. The dynamic mass virtual hosting technique - is based on automatically inserting this information into the - pathname of the file that is used to satisfy the request. This - is done most easily using <a - href="../mod/mod_vhost_alias.html"><code>mod_vhost_alias</code></a>, - but if you are using a version of Apache up to 1.3.6 then you - must use <a - href="../mod/mod_rewrite.html"><code>mod_rewrite</code></a>. - Both of these modules are disabled by default; you must enable - one of them when configuring and building Apache if you want to - use this technique.</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 which is used by Apache to generate - self-referential URLs, etc. It is configured with the - <code>ServerName</code> directive, and it is available to CGIs - via the <code>SERVER_NAME</code> environment variable. The - actual value used at run time is controlled by the <a - href="../mod/core.html#usecanonicalname"><code>UseCanonicalName</code></a> - setting. With <code>UseCanonicalName Off</code> the server name - comes from the contents of the <code>Host:</code> header in the - request. With <code>UseCanonicalName DNS</code> it comes from a - reverse DNS lookup of the virtual host's IP address. The former - setting is used for name-based dynamic virtual hosting, and the - latter is used for IP-based hosting. If Apache cannot work out - the server name because there is no <code>Host:</code> header - or the DNS lookup fails then the value configured with - <code>ServerName</code> is used instead.</p> - - <p>The other thing to `fake' is the document root (configured - with <code>DocumentRoot</code> and available to CGIs via the - <code>DOCUMENT_ROOT</code> environment variable). In a normal - configuration this setting is used by the core module when - mapping URIs to filenames, but when the server is configured to - do dynamic virtual hosting that job is taken over by another - module (either <code>mod_vhost_alias</code> or - <code>mod_rewrite</code>) which has a different way of doing - the mapping. Neither of these modules is responsible for - setting the <code>DOCUMENT_ROOT</code> environment variable so - if any CGIs or SSI documents make use of it they will get a - misleading value.</p> - <hr /> - - <h2><a id="simple" name="simple">Simple 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 using <code>mod_vhost_alias</code>.</p> -<pre> -# get the server name from the Host: header -UseCanonicalName Off - -# this log format can be split per-virtual-host based on the first field -LogFormat "%V %h %l %u %t \"%r\" %s %b" vcommon -CustomLog logs/access_log vcommon - -# include the server name in the filenames used to satisfy requests -VirtualDocumentRoot /www/hosts/%0/docs -VirtualScriptAlias /www/hosts/%0/cgi-bin -</pre> - - <p>This configuration can be changed into an IP-based virtual - hosting solution by just turning <code>UseCanonicalName - Off</code> into <code>UseCanonicalName DNS</code>. The server - name that is inserted into the filename is then derived from - the IP address of the virtual host.</p> - <hr /> - - <h2><a id="homepages" 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 a slightly more complicated - configuration 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> -# all the preliminary stuff is the same as above, then - -# include part of the server name in the filenames -VirtualDocumentRoot /www/hosts/%2/docs - -# single cgi-bin directory -ScriptAlias /cgi-bin/ /www/std-cgi/ -</pre> - - <p>There are examples of more complicated - <code>VirtualDocumentRoot</code> settings in <a - href="../mod/mod_vhost_alias.html">the - <code>mod_vhost_alias</code> documentation</a>.</p> - <hr /> - - <h2><a id="combinations" 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 virtual hosting 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 conventional - <code><VirtualHost></code> configuration sections.</p> -<pre> -UseCanonicalName Off - -LogFormat "%V %h %l %u %t \"%r\" %s %b" vcommon - -<Directory /www/commercial> - Options FollowSymLinks - AllowOverride All -</Directory> - -<Directory /www/homepages> - Options FollowSymLinks - AllowOverride None -</Directory> - -<VirtualHost 111.22.33.44> - ServerName www.commercial.isp.com - - CustomLog logs/access_log.commercial vcommon - - VirtualDocumentRoot /www/commercial/%0/docs - VirtualScriptAlias /www/commercial/%0/cgi-bin -</VirtualHost> - -<VirtualHost 111.22.33.45> - ServerName www.homepages.isp.com - - CustomLog logs/access_log.homepages vcommon - - VirtualDocumentRoot /www/homepages/%0/docs - ScriptAlias /cgi-bin/ /www/std-cgi/ -</VirtualHost> -</pre> - <hr /> - - <h2><a id="ipbased" name="ipbased">More efficient IP-based - virtual hosting</a></h2> - - <p>After <a href="#simple">the first example</a> I noted that - it is easy to turn it into an IP-based virtual hosting setup. - Unfortunately that configuration is not very efficient because - it requires a DNS lookup for every request. This can be avoided - by laying out the filesystem according to the IP addresses - themselves rather than the corresponding names and changing the - logging similarly. Apache will then usually not need to work - out the server name and so incur a DNS lookup.</p> -<pre> -# get the server name from the reverse DNS of the IP address -UseCanonicalName DNS - -# include the IP address in the logs so they may be split -LogFormat "%A %h %l %u %t \"%r\" %s %b" vcommon -CustomLog logs/access_log vcommon - -# include the IP address in the filenames -VirtualDocumentRootIP /www/hosts/%0/docs -VirtualScriptAliasIP /www/hosts/%0/cgi-bin -</pre> - <hr /> - - <h2><a id="oldversion" name="oldversion">Using older versions - of Apache</a></h2> - - <p>The examples above rely on <code>mod_vhost_alias</code> - which appeared after version 1.3.6. If you are using a version - of Apache without <code>mod_vhost_alias</code> then you can - implement this technique with <code>mod_rewrite</code> as - illustrated below, but only for Host:-header-based virtual - hosts.</p> - - <p>In addition there are some things to beware of with logging. - Apache 1.3.6 is the first version to include the - <code>%V</code> log format directive; in versions 1.3.0 - 1.3.3 - the <code>%v</code> option did what <code>%V</code> does; - version 1.3.4 has no equivalent. In all these versions of - Apache the <code>UseCanonicalName</code> directive can appear - in <code>.htaccess</code> files which means that customers can - cause the wrong thing to be logged. Therefore the best thing to - do is use the <code>%{Host}i</code> directive which logs the - <code>Host:</code> header directly; note that this may include - <code>:port</code> on the end which is not the case for - <code>%V</code>.</p> - <hr /> - - <h2><a id="simple.rewrite" name="simple.rewrite">Simple dynamic - virtual hosts using <code>mod_rewrite</code></a></h2> - - <p>This extract from <code>httpd.conf</code> does the same - thing as <a href="#simple">the first example</a>. The first - half is very similar to the corresponding part above but with - some changes for backward compatibility and to make the - <code>mod_rewrite</code> part work properly; the second half - configures <code>mod_rewrite</code> to do the actual work.</p> - - <p>There are a couple of especially tricky bits: By default, - <code>mod_rewrite</code> runs before the other URI translation - modules (<code>mod_alias</code> etc.) so if they are used then - <code>mod_rewrite</code> must be configured to accommodate - them. Also, mome magic must be performed to do a - per-dynamic-virtual-host equivalent of - <code>ScriptAlias</code>.</p> -<pre> -# get the server name from the Host: header -UseCanonicalName Off - -# splittable logs -LogFormat "%{Host}i %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 id="homepages.rewrite" name="homepages.rewrite">A - homepages system using <code>mod_rewrite</code></a></h2> - - <p>This does the same thing as <a href="#homepages">the second - example</a>.</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 ${lowercase:%{SERVER_NAME}} ^www\.[a-z-]+\.isp\.com$ - -# 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:%{SERVER_NAME}}$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 id="xtra-conf" name="xtra-conf">Using a separate virtual - host configuration file</a></h2> - - <p>This arrangement uses more advanced <code>mod_rewrite</code> - features to get the translation from virtual host to document - root from a separate configuration file. This provides more - flexibility but requires more complicated configuration.</p> - - <p>The <code>vhost.map</code> file contains something like - this:</p> -<pre> -www.customer-1.com /www/customers/1 -www.customer-2.com /www/customers/2 -# ... -www.customer-N.com /www/customers/N -</pre> - <br /> - <br /> - - - <p>The <code>http.conf</code> contains this:</p> -<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> - <br /> - <br /> - <!--#include virtual="footer.html" --> - </body> -</html> - |