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604 lines
34 KiB
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<meta name="DC.Title" content="Module mod_vhost_alias" />
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<meta name="copyright" content="(C) Copyright IBM Corporation 2002,2006" />
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<title>Module mod_vhost_alias</title>
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</head>
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<body id="rzaiemod_vhost_alias"><a name="rzaiemod_vhost_alias"><!-- --></a>
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<!-- Java sync-link --><script language="Javascript" src="../rzahg/synch.js" type="text/javascript"></script>
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<!--Java sync-link--><h1 class="topictitle1">Module mod_vhost_alias</h1>
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<div><div class="important"><span class="importanttitle">Important:</span> Information
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for this topic supports the latest PTF levels for HTTP Server for i5/OS .
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It is recommended that you install the latest PTFs to upgrade to the latest
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level of the HTTP Server for i5/OS. Some of the topics documented here are
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not available prior to this update. See <a href="http://www-03.ibm.com/servers/eserver/iseries/software/http/services/service.html" target="_blank">http://www.ibm.com/servers/eserver/iseries/software/http/services/service.htm</a> <img src="www.gif" alt="Link outside Information Center" /> for more information. </div>
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<p><strong>Summary</strong></p>
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<p>The module mod_vhost_alias provides support for dynamically configured
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mass virtual hosting. </p>
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<p><strong>Virtual hosting</strong></p>
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<p>The term Virtual Host refers to the practice of maintaining more than one
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server on one machine or server instance, as differentiated by their apparent
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hostname (or server instance name). For example, it is often desirable for
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companies sharing a web server to have their own domains, with web servers
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accessible as www.company1.com and www.company2.com, without requiring the
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user to know extra path information.</p>
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<p>HTTP Server (powered by Apache) supports two types of virtual hosting,
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they are IP-based Virtual Host and Name-based Virtual Host. As the term IP-based
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indicates, the server must have a different IP address for each IP-based virtual
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host. This can be achieved by the machine having several physical network
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connections, or by use of virtual interfaces that are supported by most modern
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operating systems.</p>
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<p>While the approach with IP-based Virtual Hosts works well, it is not the
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most elegant solution, because a dedicated IP address is needed for every
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virtual host and is hard to implement on some machines. The HTTP/1.1 protocol
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contains a method for the server to identify what name it is being addressed
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as.</p>
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<p>The benefits of using the name-based virtual host support is a practically
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unlimited number of servers, ease of configuration and use, and no additional
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hardware or software requirements. The main disadvantage is that the client
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must support this part of the protocol. The latest versions of most browsers
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(e.g. HTTP 1.1) do, but there are still old browsers (e.g. HTTP 1.0) in use
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that do not. This can cause problems, although a possible solution is addressed
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below.</p>
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<p><strong>Using non-IP virtual hosts</strong></p>
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<p>The notable difference between IP-based and name-based virtual host configuration
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is the NameVirtualHost directive that specifies an IP address that should
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be used as a target for name-based virtual hosts. For example, suppose that
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both www.domain.tld and www.otherdomain.tld point at the IP address 111.22.33.44.
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Simply add to one of the configuration files (most likely httpd.conf or srm.conf)
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code similar to the following: </p>
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<pre class="block">NameVirtualHost 111.22.33.44
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<VirtualHost 111.22.33.44>
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ServerName www.domain.tld
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DocumentRoot /www/domain
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</VirtualHost>
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<VirtualHost 111.22.33.44>
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ServerName www.otherdomain.tld
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DocumentRoot /www/otherdomain
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</VirtualHost> </pre>
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<p>Of course, any additional directives can (and should) be placed into the <VirtualHost>
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section. To make this work, make sure that the names www.domain.tld and www.otherdomain.tld
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are pointing to the IP address 111.22.33.44 </p>
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<div class="note"><span class="notetitle">Note:</span> When you specify an IP address in a NameVirtualHost directive, requests
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to that IP address are only served by matching <VirtualHost>s. The main
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server is never served from the specified IP address. If you start to use
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virtual hosts you should stop using the main server as an independent server
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and use it as a place for configuration directives that are common for all
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your virtual hosts. In other words, you should add a <VirtualHost> section
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for every server (hostname) you want to maintain on your server. </div>
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<p>Additionally, many servers may want to be accessible by more than one name.
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For example, the example server might want to be accessible as domain.tld,
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or www2.domain.tld, assuming the IP addresses pointed to the same server.
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In fact, one might want it so that all addresses at domain.tld were picked
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up by the server. This is possible with the ServerAlias directive, placed
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inside the <VirtualHost> section. For example: </p>
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<pre class="block">ServerAlias domain.tld *.domain.tld</pre>
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<div class="note"><span class="notetitle">Note:</span> You can use * and ? as wild-card characters. </div>
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<p>You might also need ServerAlias if you are serving local users who do not
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always include the domain name. For example, if local users are familiar with
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typing "www" or "www.example" then you will need to add ServerAlias www www.example.
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It isn't possible for the server to know what domain the client uses for their
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name resolution because the client doesn't provide that information in the
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request. The ServerAlias directive provides a means for different hostnames
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to point to the same virtual host. </p>
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<p><strong>Dynamic virtual hosting</strong></p>
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<p>A virtual host is defined by two pieces of information: its IP address,
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and the contents of the Host: header in the HTTP request. The dynamic mass
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virtual hosting technique is based on automatically inserting this information
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into the pathname of the file that is used to satisfy the request. This is
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done most easily using mod_vhost_alias. </p>
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<p>A couple of things need to be `faked', that being specific parameters with
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incorrect parameter values, to make the dynamic virtual host look like a normal
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one. The most important is the server name which is used by HTTP Server to
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generate a self referencing URLs. It is configured with the ServerName directive,
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and it is available to CGIs via the SERVER_NAME environment variable. The
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actual value used at run time is controlled by the UseCanonicalName setting.
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With UseCanonicalName off the server name comes from the contents of the Host:
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header in the request. With UseCanonicalName DNS it comes from a reverse DNS
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lookup of the virtual host's IP address. The former setting is used for name-based
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dynamic virtual hosting, and the latter is used for IP-based hosting. If HTTP
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Server cannot work out the server name because there is no Host: header or
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the DNS lookup fails then the value configured with ServerName is used instead.
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</p>
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<p>The other thing to `fake' is the document root (configured with DocumentRoot
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and available to CGIs via the DOCUMENT_ROOT environment variable). This setting
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is used by the core module when mapping URIs to filenames, but when the server
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is configured to do dynamic virtual hosting that job is taken over by the
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mod_vhost_alias module. If any CGIs or SSI documents make use of the DOCUMENT_ROOT
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environment variable they will therefore get a misleading value; there is
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not any way to change DOCUMENT_ROOT dynamically. </p>
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<p><strong>Motivation for dynamic virtual hosting</strong> </p>
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<p>The techniques described here are of interest if your httpd.conf contains
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many <VirtualHost> sections that are substantially the same. For example:
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</p>
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<pre class="block">NameVirtualHost 10.22.33.44
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<VirtualHost 10.22.33.44>
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ServerName www.customer-1.com
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DocumentRoot /www/hosts/www.customer-1.com/docs
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ScriptAlias /cgi-bin/ /www/hosts/www.customer-1.com/cgi-bin
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</VirtualHost>
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<VirtualHost 10.22.33.44>
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ServerName www.customer-2.com
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DocumentRoot /www/hosts/www.customer-2.com/docs
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ScriptAlias /cgi-bin/ /www/hosts/www.customer-2.com/cgi-bin
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</VirtualHost>
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# comment line
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<VirtualHost 10.22.33.44>
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ServerName www.customer-N.com
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DocumentRoot /www/hosts/www.customer-N.com/docs
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ScriptAlias /cgi-bin/ /www/hosts/www.customer-N.com/cgi-bin
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</VirtualHost> </pre>
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<p>The basic idea is to replace all of the static <VirtualHost> configuration
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with a mechanism that works it out dynamically. This has a number of advantages: </p>
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<ol><li>Your configuration file is smaller so HTTP Server starts faster and uses
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less memory. </li>
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<li>Adding virtual hosts is simply a matter of creating the appropriate directories
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in the filesystem and entries in the DNS - you do not need to configure or
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restart HTTP Server (powered by Apache).</li>
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</ol>
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<p>The main disadvantage is that you cannot have a different log file for
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each virtual host; however if you have very many virtual hosts then doing
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this is dubious anyway because it eats file descriptors. It is better to log
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to a pipe or a fifo and arrange for the process at the other end to distribute
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the logs to the customers (it can also accumulate statistics).</p>
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<p>A request for http://www.example.isp.com/directory/file.html will be satisfied
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by the file: </p>
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<pre class="block">/usr/local/apache/vhosts/isp.com/e/x/a/example/directory/file.html. </pre>
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<p>A more even spread of files can be achieved by hashing from the end of
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the name, for example: </p>
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<pre class="block">VirtualDocumentRoot /usr/local/apache/vhosts/%3+/%2.-1/%2.-2/%2.-3/%2</pre>
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<p>The example request would come from /usr/local/apache/vhosts/isp.com/e/l/p/example/directory/file.html.
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Alternatively you might use: </p>
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<pre class="block">VirtualDocumentRoot /usr/local/apache/vhosts/%3+/%2.1/%2.2/%2.3/%2.4+</pre>
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<p>The example request would come from /usr/local/apache/vhosts/isp.com/e/x/a/mple/directory/file.html.
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</p>
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<p><strong>Simple dynamic virtual hosts</strong></p>
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<p>This extract from httpd.conf implements the virtual host arrangement outlined
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in the Motivation section above, but in a generic fashion using mod_vhost_alias.
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</p>
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<pre class="block"># get the server name from the Host: header
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UseCanonicalName off
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# this log format can be split per-virtual-host based on the first field
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LogFormat "%V %h %l %u %t \"%r\" %s %b" vcommon
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CustomLog logs/access_log vcommon
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# include the server name in the filenames used to satisfy requests
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VirtualDocumentRoot /www/hosts/%0/docs
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VirtualScriptAlias /www/hosts/%0/cgi-bin </pre>
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<p>This configuration can be changed into an IP-based virtual hosting solution
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by just turning UseCanonicalName off into UseCanonicalName DNS. The server
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name that is inserted into the filename is then derived from the IP address
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of the virtual host. </p>
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<p><strong>A virtually hosted homepages system </strong></p>
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<p>This is an adjustment of the above system tailored for an ISP's homepages
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server. Using a slightly more complicated configuration we can select substrings
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of the server name to use in the filename so that e.g. the documents for www.user.isp.com
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are found in /home/user/. It uses a single cgi-bin directory instead of one
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per virtual host. </p>
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<pre class="block"># all the preliminary stuff is the same as above, then
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# include part of the server name in the filenames
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VirtualDocumentRoot /www/hosts/%2/docs
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# single cgi-bin directory
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ScriptAlias /cgi-bin/ /www/std-cgi/</pre>
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<p><strong>Use more than one virtual hosting system on the same server </strong></p>
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<p>With more complicated setups you can use HTTP Server's normal <VirtualHost>
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directives to control the scope of the various virtual hosting configurations.
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For example, you could have one IP address for homepages customers and another
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for commercial customers with the following setup. This can of course be combined
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with conventional <VirtualHost> configuration sections. </p>
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<pre class="block">UseCanonicalName off
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LogFormat "%V %h %l %u %t \"%r\" %s %b" vcommon
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<Directory /www/commercial>
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Options FollowSymLinks
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AllowOverride All
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</Directory>
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<Directory /www/homepages>
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Options FollowSymLinks
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AllowOverride None
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</Directory>
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<VirtualHost 10.22.33.44>
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ServerName www.commercial.isp.com
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CustomLog logs/access_log.commercial vcommon
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VirtualDocumentRoot /www/commercial/%0/docs
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VirtualScriptAlias /www/commercial/%0/cgi-bin
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</VirtualHost>
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<VirtualHost 10.22.33.45>
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ServerName www.homepages.isp.com
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CustomLog logs/access_log.homepages vcommon
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VirtualDocumentRoot /www/homepages/%0/docs
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ScriptAlias /cgi-bin/ /www/std-cgi/
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</VirtualHost></pre>
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<p><strong>Directory name interpolation</strong> </p>
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<p>All the directives in this module interpolate (insert) a string into a
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pathname. The interpolated string may either be the server name (see <a href="rzaiemod_core.htm#usecanonicalname">UseCanonicalName</a> for more information)
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or the IP address of the virtual host on the server in dotted-quad format.
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The interpolation is controlled by specifiers inspired by UNIX<sup>®</sup> printf which
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have a number of formats: </p>
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<div class="tablenoborder"><table cellpadding="4" cellspacing="0" summary="" frame="border" border="1" rules="all"><thead align="left"><tr><th valign="top" id="d0e137">Specifier</th>
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<th valign="top" id="d0e139">Description</th>
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</tr>
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</thead>
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<tbody><tr><td valign="top" headers="d0e137 ">%%</td>
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<td valign="top" headers="d0e139 ">Insert a % sign</td>
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</tr>
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<tr><td valign="top" headers="d0e137 ">%p</td>
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<td valign="top" headers="d0e139 ">Insert the port number of the virtual host</td>
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</tr>
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<tr><td valign="top" headers="d0e137 ">%N.M</td>
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<td valign="top" headers="d0e139 ">Insert (part of) the interpolated string</td>
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</tr>
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</tbody>
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</table>
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</div>
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<p><strong>N</strong> and <strong>M</strong> are used to specify substrings of the interpolated
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string. <strong>N</strong> selects from the period separated components of the interpolated
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string, and <strong>M</strong> selects characters within whatever <strong>N</strong> has selected. <strong>M</strong> is
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optional and defaults to zero if it is not present. The period (.) must be
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present if and only if <strong>M</strong> is present. The interpretation is as follows:
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</p>
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<div class="tablenoborder"><table cellpadding="4" cellspacing="0" summary="" frame="border" border="1" rules="all"><thead align="left"><tr><th valign="top" id="d0e185">N.M interpretation</th>
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<th valign="top" id="d0e187">Description</th>
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</tr>
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</thead>
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<tbody><tr><td valign="top" headers="d0e185 ">0</td>
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<td valign="top" headers="d0e187 ">The whole name.</td>
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</tr>
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<tr><td valign="top" headers="d0e185 ">1</td>
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<td valign="top" headers="d0e187 ">The first part.</td>
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</tr>
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<tr><td valign="top" headers="d0e185 ">2</td>
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<td valign="top" headers="d0e187 ">The second part.</td>
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</tr>
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<tr><td valign="top" headers="d0e185 ">-1</td>
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<td valign="top" headers="d0e187 ">The last part.</td>
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</tr>
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|
|
<tr><td valign="top" headers="d0e185 ">-2</td>
|
||
|
|
<td valign="top" headers="d0e187 ">The next to last part.</td>
|
||
|
|
</tr>
|
||
|
|
<tr><td valign="top" headers="d0e185 ">2+</td>
|
||
|
|
<td valign="top" headers="d0e187 ">The second and all subsequent parts.</td>
|
||
|
|
</tr>
|
||
|
|
<tr><td valign="top" headers="d0e185 ">-2+</td>
|
||
|
|
<td valign="top" headers="d0e187 ">The next to last part and all preceding parts.</td>
|
||
|
|
</tr>
|
||
|
|
<tr><td valign="top" headers="d0e185 ">1+ and -1+</td>
|
||
|
|
<td valign="top" headers="d0e187 ">The same as 0 (zero).</td>
|
||
|
|
</tr>
|
||
|
|
</tbody>
|
||
|
|
</table>
|
||
|
|
</div>
|
||
|
|
<p>If <strong>N</strong> or <strong>M</strong> is greater than the number of parts available a
|
||
|
|
single underscore is interpolated.</p>
|
||
|
|
<p>For a simple name-based virtual hosts you might use the following directives
|
||
|
|
in your server configuration file: </p>
|
||
|
|
<pre class="block">UseCanonicalName off
|
||
|
|
|
||
|
|
VirtualDocumentRoot
|
||
|
|
/usr/local/www.example.isp.com/vhosts/%0
|
||
|
|
A request for http://www.example.com/directory/file.html will be satisfied by the
|
||
|
|
file /usr/local/www.example.isp.com/vhosts/www.example.com/directory/file.html.</pre>
|
||
|
|
<p>For a very large number of virtual hosts it is a good idea to arrange the
|
||
|
|
files to reduce the size of the vhosts directory. To do this you might use
|
||
|
|
the following in your configuration file:</p>
|
||
|
|
<pre class="block">UseCanonicalName off
|
||
|
|
|
||
|
|
VirtualDocumentRoot
|
||
|
|
/usr/local/www.example.isp.com/vhosts/%3+/%2.1/%2.2/%2.3/%2
|
||
|
|
A request for http://www.example.isp.com/directory/file.html will be satisfied by
|
||
|
|
the file /usr/local/www.example.isp.com/isp.com/e/x/a/example/directory/file.html.</pre>
|
||
|
|
<p>A more even spread of files can be achieved by hashing from the end of
|
||
|
|
the name, for example:</p>
|
||
|
|
<pre class="block">VirtualDocumentRoot
|
||
|
|
/usr/web/www.example.isp.com/vhosts/%3+/%2.-1/%2.-2/%2.-3/%2</pre>
|
||
|
|
<p>The example request would come from /usr/web/www.example.isp.com/vhosts/isp.com/e/l/p/example/directory/file.html.
|
||
|
|
Alternatively you might use:</p>
|
||
|
|
<pre class="block">VirtualDocumentRoot
|
||
|
|
/usr/local/www.example.isp.com/vhosts/%3+/%2.1/%2.2/%2.3/%2.4+</pre>
|
||
|
|
<p>The example request would come from /usr/web/www.example.isp.com/vhosts/isp.com/e/x/a/mple/directory/file.html.
|
||
|
|
For IP-based virtual hosting you might use the following in your configuration
|
||
|
|
file:</p>
|
||
|
|
<pre class="block">UseCanonicalName DNS
|
||
|
|
|
||
|
|
VirtualDocumentRootIP /usr/local/www.example.isp.com/vhost/%1/%2/%3/%4/docs
|
||
|
|
VirtualScriptAliasIP
|
||
|
|
/usr/local/www.example.isp.com/vhost/%1/%2/%3/%4/cgi-bin</pre>
|
||
|
|
<p>A request for http://www.example.isp.com/directory/file.html would be satisfied
|
||
|
|
by the file /usr/local/www.example.isp.com/10/20/30/40/docs/directory/file.html
|
||
|
|
if the IP address of www.example.com were 10.20.30.40. A request for http://www.example.isp.com/cgi-bin/script.pl
|
||
|
|
would be satisfied by executing the program /usr/local/www.example.isp.com/10/20/30/40/cgi-bin/script.pl. </p>
|
||
|
|
<p>The LogFormat directives %V and %A are useful in conjunction with this
|
||
|
|
module. See <a href="rzaiemod_log_config.htm#logformat">LogFormat</a> for
|
||
|
|
more information.</p>
|
||
|
|
<p><strong>Directives</strong></p>
|
||
|
|
<ul><li><a href="#virtualdocumentroot">VirtualDocumentRoot</a></li>
|
||
|
|
<li><a href="#virtualdocumentrootip">VirtualDocumentRootIP</a></li>
|
||
|
|
<li><a href="#virtualscriptalias">VirtualScriptAlias</a></li>
|
||
|
|
<li><a href="#virtualscriptaliasip">VirtualScriptAliasIP</a></li>
|
||
|
|
</ul>
|
||
|
|
</div>
|
||
|
|
<div class="hr" id="virtualdocumentroot"><a name="virtualdocumentroot"><!-- --></a><h2 class="topictitle2">VirtualDocumentRoot</h2>
|
||
|
|
<div>
|
||
|
|
<div class="tablenoborder"><table cellpadding="4" cellspacing="0" summary="" frame="void" border="0" rules="none"><tbody><tr><td colspan="2" valign="top"><strong><a href="rzaiedirective-dict.htm#rzaiedirective-dict__Module">Module</a></strong>: mod_vhost_alias </td>
|
||
|
|
</tr>
|
||
|
|
<tr><td colspan="2" valign="top"><strong><a href="rzaiedirective-dict.htm#rzaiedirective-dict__Syntax">Syntax</a></strong>: VirtualDocumentRoot <em>interpolated-directory</em> </td>
|
||
|
|
</tr>
|
||
|
|
<tr><td colspan="2" valign="top"><strong><a href="rzaiedirective-dict.htm#rzaiedirective-dict__Default">Default</a></strong>: none </td>
|
||
|
|
</tr>
|
||
|
|
<tr><td colspan="2" valign="top"><strong><a href="rzaiedirective-dict.htm#rzaiedirective-dict__Context">Context</a></strong>: <span id="virtualdocumentroot__virtualdocumentroot_context"><a name="virtualdocumentroot__virtualdocumentroot_context"><!-- --></a>server
|
||
|
|
config, virtual host </span></td>
|
||
|
|
</tr>
|
||
|
|
<tr><td colspan="2" valign="top"><strong><a href="rzaiedirective-dict.htm#rzaiedirective-dict__Override">Override</a></strong>: none </td>
|
||
|
|
</tr>
|
||
|
|
<tr><td colspan="2" valign="top"><strong><a href="rzaiedirective-dict.htm#rzaiedirective-dict__Origin">Origin</a></strong>: <span id="virtualdocumentroot__virtualdocumentroot_origin"><a name="virtualdocumentroot__virtualdocumentroot_origin"><!-- --></a>Apache </span></td>
|
||
|
|
</tr>
|
||
|
|
<tr><td colspan="2" valign="top"><strong><a href="rzaiedirective-dict.htm#rzaiedirective-dict__UsageConsiderations">Usage Considerations</a></strong>: A LoadModule is required in
|
||
|
|
the config file prior to using the directive. The statement should be as follows:
|
||
|
|
LoadModule vhost_alias_module /QSYS.LIB/QHTTPSVR.LIB/QZSRCORE.SRVPGM </td>
|
||
|
|
</tr>
|
||
|
|
<tr><td colspan="2" valign="top"><strong><a href="rzaiedirective-dict.htm#rzaiedirective-dict__Example">Example</a></strong>: See below.</td>
|
||
|
|
</tr>
|
||
|
|
</tbody>
|
||
|
|
</table>
|
||
|
|
</div>
|
||
|
|
<p>The VirtualDocumentRoot directive allows you to determine where the server
|
||
|
|
will finds your documents based on the value of the server name. The result
|
||
|
|
of expanding interpolated-directory is used as the root of the document tree
|
||
|
|
in a similar manner to the DocumentRoot disabled. See <a href="rzaiemod_core.htm#documentroot">DocumentRoot</a> for more information. </p>
|
||
|
|
<p>If interpolated-directory is <em>none</em> then VirtualDocumentRoot is disabled.
|
||
|
|
This directive cannot be used in the same context as VirtualDocumentRootIP.
|
||
|
|
See <a href="#virtualdocumentrootip">VirtualDocumentRootIP</a> for more information.</p>
|
||
|
|
<dl class="block"><dt class="dlterm"><strong>Parameter</strong>: <em>interpolated-directory </em></dt>
|
||
|
|
<dd><ul><li>The <em>interpolated-directory</em> parameter the full path to a directory. </li>
|
||
|
|
</ul>
|
||
|
|
</dd>
|
||
|
|
</dl>
|
||
|
|
<p>For example, a simple dynamic virtual host:</p>
|
||
|
|
<pre class="block"># LocalModule directive required
|
||
|
|
LoadModule vhost_alias_module /QSYS.LIB/QHTTPSVR.LIB/QZSRCORE.SRVPGM
|
||
|
|
# 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/web/%0/docs</pre>
|
||
|
|
<p>The next example is an adjustment of the above, system tailored for an
|
||
|
|
ISP's homepage 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 www.user.isp.com are found in /home/user/. It uses a single
|
||
|
|
cgi-bin directory instead of one per virtual host: </p>
|
||
|
|
<pre class="block"># LocalModule directive required
|
||
|
|
LoadModule vhost_alias_module /QSYS.LIB/QHTTPSVR.LIB/QZSRCORE.SRVPGM
|
||
|
|
# get the server name from the Host: header
|
||
|
|
UseCanonicalName off
|
||
|
|
# include part of the server name in the filenames
|
||
|
|
VirtualDocumentRoot /usr/web/hosts/%2/docs
|
||
|
|
# single cgi-bin directory
|
||
|
|
ScriptAlias /cgi-bin/ /usr/web/std-cgi/ </pre>
|
||
|
|
<div class="note"><span class="notetitle">Note:</span> This configuration can be changed into an IP-based virtual hosting solution
|
||
|
|
by just turning UseCanonicalName off into UseCanonicalName DNS. The server
|
||
|
|
name that is inserted into the filename is then derived from the IP address
|
||
|
|
of the virtual host. See <a href="rzaiemod_core.htm#usecanonicalname">UseCanonicalName</a> for more information.</div>
|
||
|
|
</div>
|
||
|
|
</div>
|
||
|
|
<div class="hr" id="virtualdocumentrootip"><a name="virtualdocumentrootip"><!-- --></a><h2 class="topictitle2">VirtualDocumentRootIP</h2>
|
||
|
|
<div>
|
||
|
|
<div class="tablenoborder"><table cellpadding="4" cellspacing="0" summary="" frame="void" border="0" rules="none"><tbody><tr><td colspan="2" valign="top"><strong><a href="rzaiedirective-dict.htm#rzaiedirective-dict__Module">Module</a></strong>: mod_vhost_alias </td>
|
||
|
|
</tr>
|
||
|
|
<tr><td colspan="2" valign="top"><strong><a href="rzaiedirective-dict.htm#rzaiedirective-dict__Syntax">Syntax</a></strong>: VirtualDocumentRootIP <em>interpolated-directory</em> </td>
|
||
|
|
</tr>
|
||
|
|
<tr><td colspan="2" valign="top"><strong><a href="rzaiedirective-dict.htm#rzaiedirective-dict__Default">Default</a></strong>: none </td>
|
||
|
|
</tr>
|
||
|
|
<tr><td colspan="2" valign="top"><strong><a href="rzaiedirective-dict.htm#rzaiedirective-dict__Context">Context</a></strong>: <span id="virtualdocumentrootip__virtualdocumentrootip_context"><a name="virtualdocumentrootip__virtualdocumentrootip_context"><!-- --></a>server
|
||
|
|
config, virtual host </span></td>
|
||
|
|
</tr>
|
||
|
|
<tr><td colspan="2" valign="top"><strong><a href="rzaiedirective-dict.htm#rzaiedirective-dict__Override">Override</a></strong>: none </td>
|
||
|
|
</tr>
|
||
|
|
<tr><td colspan="2" valign="top"><strong><a href="rzaiedirective-dict.htm#rzaiedirective-dict__Origin">Origin</a></strong>: <span id="virtualdocumentrootip__virtualdocumentrootip_origin"><a name="virtualdocumentrootip__virtualdocumentrootip_origin"><!-- --></a>Apache </span></td>
|
||
|
|
</tr>
|
||
|
|
<tr><td colspan="2" valign="top"><strong><a href="rzaiedirective-dict.htm#rzaiedirective-dict__UsageConsiderations">Usage Considerations</a></strong>: A LoadModule is required in
|
||
|
|
the config file prior to using the directive. The statement should be as follows:
|
||
|
|
LoadModule vhost_alias_module /QSYS.LIB/QHTTPSVR.LIB/QZSRCORE.SRVPGM </td>
|
||
|
|
</tr>
|
||
|
|
<tr><td colspan="2" valign="top"><strong><a href="rzaiedirective-dict.htm#rzaiedirective-dict__Example">Example</a></strong>: See <a href="#virtualdocumentroot">VirtualDocumentRoot</a>.</td>
|
||
|
|
</tr>
|
||
|
|
</tbody>
|
||
|
|
</table>
|
||
|
|
</div>
|
||
|
|
<dl class="block"><dt class="dlterm"><strong>Parameter</strong>: <em>interpolated-directory </em></dt>
|
||
|
|
<dd><ul><li>The <em>interpolated-directory</em> parameter the full path to a directory. </li>
|
||
|
|
</ul>
|
||
|
|
</dd>
|
||
|
|
</dl>
|
||
|
|
<p>More complicated setups can use the server's normal <VirtualHost> directives
|
||
|
|
to control the scope of the various virtual hosting configurations. For example,
|
||
|
|
you could have one IP address for home page customers and another for commercial
|
||
|
|
customers with the following directives. This can of course be combined with
|
||
|
|
conventional <VirtualHost> configuration sections. </p>
|
||
|
|
<pre class="block">UseCanonicalName off
|
||
|
|
|
||
|
|
LogFormat "%V %h %l %u %t \"%r\" %s %b" vcommon
|
||
|
|
|
||
|
|
<Directory /usr/web/commercial>
|
||
|
|
Options FollowSymLinks
|
||
|
|
AllowOverride All
|
||
|
|
</Directory>
|
||
|
|
|
||
|
|
<Directory /usr/web/homepages>
|
||
|
|
Options FollowSymLinks
|
||
|
|
AllowOverride None
|
||
|
|
</Directory>
|
||
|
|
# LocalModule directive required
|
||
|
|
LoadModule vhost_alias_module /QSYS.LIB/QHTTPSVR.LIB/QZSRCORE.SRVPGM
|
||
|
|
|
||
|
|
|
||
|
|
<VirtualHost 10.22.33.44>
|
||
|
|
ServerName www.commercial.isp.com
|
||
|
|
CustomLog logs/access_log.commercial vcommon
|
||
|
|
VirtualDocumentRoot /usr/web/commercial/%0/docs
|
||
|
|
VirtualScriptAlias /usr/web/commercial/%0/cgi-bin
|
||
|
|
</VirtualHost>
|
||
|
|
<VirtualHost 10.22.33.45>
|
||
|
|
ServerName www.homepages.isp.com
|
||
|
|
CustomLog logs/access_log.homepages vcommon
|
||
|
|
VirtualDocumentRoot /usr/web/homepages/%0/docs
|
||
|
|
ScriptAlias /cgi-bin/ /usr/web/std-cgi/
|
||
|
|
</VirtualHost></pre>
|
||
|
|
<p><strong>More efficient IP-based virtual hosting: </strong></p>
|
||
|
|
<p>In the first example note 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. HTTP Server will not
|
||
|
|
usually need to work out the server name and a DNS lookup. For example:</p>
|
||
|
|
<pre class="block"># Get the server name from the reverse DNS of the IP address
|
||
|
|
UseCanonicalName DNS
|
||
|
|
# LocalModule directive required
|
||
|
|
LoadModule vhost_alias_module /QSYS.LIB/QHTTPSVR.LIB/QZSRCORE.SRVPGM
|
||
|
|
|
||
|
|
# 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 /usr/web/hosts/%0/docs
|
||
|
|
VirtualScriptAliasIP /usr/web/hosts/%0/cgi-bin</pre>
|
||
|
|
<p>The VirtualDocumentRootIP directive is like the VirtualDocumentRoot directive,
|
||
|
|
except that it uses the IP address of the server end of the connection instead
|
||
|
|
of the server name. See <a href="#virtualdocumentroot">VirtualDocumentRoot</a> for more
|
||
|
|
information.</p>
|
||
|
|
</div>
|
||
|
|
</div>
|
||
|
|
<div class="hr" id="virtualscriptalias"><a name="virtualscriptalias"><!-- --></a><h2 class="topictitle2">VirtualScriptAlias</h2>
|
||
|
|
<div>
|
||
|
|
<div class="tablenoborder"><table cellpadding="4" cellspacing="0" summary="" frame="void" border="0" rules="none"><tbody><tr><td colspan="2" valign="top"><strong><a href="rzaiedirective-dict.htm#rzaiedirective-dict__Module">Module</a></strong>: mod_vhost_alias </td>
|
||
|
|
</tr>
|
||
|
|
<tr><td colspan="2" valign="top"><strong><a href="rzaiedirective-dict.htm#rzaiedirective-dict__Syntax">Syntax</a></strong>: VirtualScriptAlias<em> interpolated-directory </em></td>
|
||
|
|
</tr>
|
||
|
|
<tr><td colspan="2" valign="top"><strong><a href="rzaiedirective-dict.htm#rzaiedirective-dict__Default">Default</a></strong>: none </td>
|
||
|
|
</tr>
|
||
|
|
<tr><td colspan="2" valign="top"><strong><a href="rzaiedirective-dict.htm#rzaiedirective-dict__Context">Context</a></strong>: <span id="virtualscriptalias__virtualscriptalias_context"><a name="virtualscriptalias__virtualscriptalias_context"><!-- --></a>server
|
||
|
|
config, virtual host </span></td>
|
||
|
|
</tr>
|
||
|
|
<tr><td colspan="2" valign="top"><strong><a href="rzaiedirective-dict.htm#rzaiedirective-dict__Override">Override</a></strong>: none </td>
|
||
|
|
</tr>
|
||
|
|
<tr><td colspan="2" valign="top"><strong><a href="rzaiedirective-dict.htm#rzaiedirective-dict__Origin">Origin</a></strong>: <span id="virtualscriptalias__virtualscriptalias_origin"><a name="virtualscriptalias__virtualscriptalias_origin"><!-- --></a>Apache </span></td>
|
||
|
|
</tr>
|
||
|
|
<tr><td colspan="2" valign="top"><strong><a href="rzaiedirective-dict.htm#rzaiedirective-dict__UsageConsiderations">Usage Considerations</a></strong>: A LoadModule is required in
|
||
|
|
the config file prior to using the directive. The statement should be as follows:
|
||
|
|
LoadModule vhost_alias_module /QSYS.LIB/QHTTPSVR.LIB/QZSRCORE.SRVPGM </td>
|
||
|
|
</tr>
|
||
|
|
<tr><td colspan="2" valign="top"><strong><a href="rzaiedirective-dict.htm#rzaiedirective-dict__Example">Example</a></strong>: See below.</td>
|
||
|
|
</tr>
|
||
|
|
</tbody>
|
||
|
|
</table>
|
||
|
|
</div>
|
||
|
|
<dl class="block"><dt class="dlterm"><strong>Parameter</strong>: <em>interpolated-directory </em></dt>
|
||
|
|
<dd><ul><li>The <em>interpolated-directory</em> parameter the full path to a directory. </li>
|
||
|
|
</ul>
|
||
|
|
</dd>
|
||
|
|
</dl>
|
||
|
|
<p><strong>Using more than one virtual hosting system on the same server instance</strong>: </p>
|
||
|
|
<p>More complicated setups use the server's normal <VirtualHost> 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 directives. This can of course be combined with
|
||
|
|
conventional <VirtualHost> configuration sections.</p>
|
||
|
|
<pre class="block">UseCanonicalName off
|
||
|
|
|
||
|
|
LogFormat "%V %h %l %u %t \"%r\" %s %b" vcommon
|
||
|
|
|
||
|
|
<Directory/usr/web/commercial>
|
||
|
|
Options FollowSymLinks
|
||
|
|
AllowOverride All
|
||
|
|
|
||
|
|
|
||
|
|
</Directory>
|
||
|
|
<Directory /usr/web/homepages>
|
||
|
|
Options FollowSymLinks
|
||
|
|
AllowOverride None
|
||
|
|
</Directory>
|
||
|
|
|
||
|
|
|
||
|
|
# LocalModule directive required
|
||
|
|
LoadModule vhost_alias_module /QSYS.LIB/QHTTPSVR.LIB/QZSRCORE.SRVPGM
|
||
|
|
<VirtualHost 10.22.33.44>
|
||
|
|
ServerName www.commercial.isp.com
|
||
|
|
CustomLog logs/access_log.commercial vcommon
|
||
|
|
VirtualDocumentRoot /usr/web/commercial/%0/docs
|
||
|
|
VirtualScriptAlias /usr/web/commercial/%0/cgi-bin
|
||
|
|
</VirtualHost>
|
||
|
|
|
||
|
|
|
||
|
|
<VirtualHost 10.22.33.45>
|
||
|
|
ServerName www.homepages.isp.com
|
||
|
|
CustomLog logs/access_log.homepages vcommon
|
||
|
|
VirtualDocumentRoot /usr/web/homepages/%0/docs
|
||
|
|
ScriptAlias /cgi-bin/ /usr/web/std-cgi/
|
||
|
|
</VirtualHost></pre>
|
||
|
|
<div class="note"><span class="notetitle">Note:</span> The VirtualScriptAlias directive allows you to specify the directory
|
||
|
|
path where the server will find CGI scripts in a similar manner to <a href="#virtualdocumentroot">VirtualDocumentRoot</a> does
|
||
|
|
for other documents. In this case the target directory of the CGI scripts
|
||
|
|
must be named "cgi-bin". For example: </div>
|
||
|
|
<pre class="block">VirtualScriptAlias /user/web/commercial/%0/cgi-bin</pre>
|
||
|
|
</div>
|
||
|
|
</div>
|
||
|
|
<div class="hr" id="virtualscriptaliasip"><a name="virtualscriptaliasip"><!-- --></a><h2 class="topictitle2">VirtualScriptAliasIP</h2>
|
||
|
|
<div>
|
||
|
|
<div class="tablenoborder"><table cellpadding="4" cellspacing="0" summary="" frame="void" border="0" rules="none"><tbody><tr><td colspan="2" valign="top"><strong><a href="rzaiedirective-dict.htm#rzaiedirective-dict__Module">Module</a></strong>: mod_vhost_alias </td>
|
||
|
|
</tr>
|
||
|
|
<tr><td colspan="2" valign="top"><strong><a href="rzaiedirective-dict.htm#rzaiedirective-dict__Syntax">Syntax</a></strong>: VirtualScriptAliasIP<em> interpolated-directory</em> </td>
|
||
|
|
</tr>
|
||
|
|
<tr><td colspan="2" valign="top"><strong><a href="rzaiedirective-dict.htm#rzaiedirective-dict__Default">Default</a></strong>: none </td>
|
||
|
|
</tr>
|
||
|
|
<tr><td colspan="2" valign="top"><strong><a href="rzaiedirective-dict.htm#rzaiedirective-dict__Context">Context</a></strong>: <span id="virtualscriptaliasip__virtualscriptaliasip_context"><a name="virtualscriptaliasip__virtualscriptaliasip_context"><!-- --></a>server
|
||
|
|
config, virtual host </span></td>
|
||
|
|
</tr>
|
||
|
|
<tr><td colspan="2" valign="top"><strong><a href="rzaiedirective-dict.htm#rzaiedirective-dict__Override">Override</a></strong>: none </td>
|
||
|
|
</tr>
|
||
|
|
<tr><td colspan="2" valign="top"><strong><a href="rzaiedirective-dict.htm#rzaiedirective-dict__Origin">Origin</a></strong>: <span id="virtualscriptaliasip__virtualscriptaliasip_origin"><a name="virtualscriptaliasip__virtualscriptaliasip_origin"><!-- --></a>Apache </span></td>
|
||
|
|
</tr>
|
||
|
|
<tr><td colspan="2" valign="top"><strong><a href="rzaiedirective-dict.htm#rzaiedirective-dict__UsageConsiderations">Usage Considerations</a></strong>: A LoadModule is required in
|
||
|
|
the config file prior to using the directive. The statement should be as follows:
|
||
|
|
LoadModule vhost_alias_module /QSYS.LIB/QHTTPSVR.LIB/QZSRCORE.SRVPGM </td>
|
||
|
|
</tr>
|
||
|
|
<tr><td colspan="2" valign="top"><strong><a href="rzaiedirective-dict.htm#rzaiedirective-dict__Example">Example</a></strong>: See <a href="#virtualscriptalias">VirtualScriptAlias</a>.</td>
|
||
|
|
</tr>
|
||
|
|
</tbody>
|
||
|
|
</table>
|
||
|
|
</div>
|
||
|
|
<p>The VirtualScriptAliasIP directive is like the <a href="#virtualscriptalias">VirtualScriptAlias</a> directive,
|
||
|
|
except that it uses the IP address of the server end of the connection instead
|
||
|
|
of the server name. </p>
|
||
|
|
<dl class="block"><dt class="dlterm"><strong>Parameter</strong>: <em>interpolated-directory </em></dt>
|
||
|
|
<dd><ul><li>The <em>interpolated-directory</em> parameter the full path to a directory. </li>
|
||
|
|
</ul>
|
||
|
|
</dd>
|
||
|
|
</dl>
|
||
|
|
</div>
|
||
|
|
</div>
|
||
|
|
|
||
|
|
</body>
|
||
|
|
</html>
|