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<title>Redirecting and Remapping with mod_rewrite - Apache HTTP Server</title>
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<p class="menu"><a href="/mod/">Modules</a> | <a href="/mod/directives.html">Directives</a> | <a href="/faq/">FAQ</a> | <a href="/glossary.html">Glossary</a> | <a href="/sitemap.html">Sitemap</a></p>
<p class="apache">Apache HTTP Server Version 2.3</p>
<div id="path">
<a href="http://www.apache.org/">Apache</a> > <a href="http://httpd.apache.org/">HTTP Server</a> > <a href="http://httpd.apache.org/docs/">Documentation</a> > <a href="../">Version 2.3</a> > <a href="./">Rewrite</a></div><div id="page-content"><div id="preamble"><h1>Redirecting and Remapping with mod_rewrite</h1>
<div class="toplang">
<p><span>Available Languages: </span><a href="/en/rewrite/remapping.html" title="English"> en </a></p>
</div>
<p>This document supplements the <code class="module"><a href="/mod/mod_rewrite.html">mod_rewrite</a></code>
how you can use <code class="module"><a href="/mod/mod_rewrite.html">mod_rewrite</a></code> to redirect and remap
request. This includes many examples of common uses of mod_rewrite,
including detailed descriptions of how each works.</p>
<div class="warning">Note that many of these examples won't work unchanged in your
particular server configuration, so it's important that you understand
them, rather than merely cutting and pasting the examples into your
configuration.</div>
</div>
<div id="quickview"><ul id="toc"><li><img alt="" src="/images/down.gif" /> <a href="#old-to-new">From Old to New (internal)</a></li>
<li><img alt="" src="/images/down.gif" /> <a href="#old-to-new-extern">Rewriting From Old to New (external)</a></li>
<li><img alt="" src="/images/down.gif" /> <a href="#static-to-dynamic">From Static to Dynamic</a></li>
<li><img alt="" src="/images/down.gif" /> <a href="#backward-compatibility">Backward Compatibility for file extension change</a></li>
<li><img alt="" src="/images/down.gif" /> <a href="#multipledirs">Search for pages in more than one directory</a></li>
</ul><h3>See also</h3><ul class="seealso"><li><a href="/mod/mod_rewrite.html">Module documentation</a></li><li><a href="intro.html">mod_rewrite introduction</a></li></ul></div>
<div class="section">
<h2><a name="old-to-new" id="old-to-new">From Old to New (internal)</a></h2>
<dl>
<dt>Description:</dt>
<dd>
<p>Assume we have recently renamed the page
to provide the old URL for backward compatibility. However,
we want that users of the old URL even not recognize that
the pages was renamed - that is, we don't want the address to
change in their browser.</p>
</dd>
<dt>Solution:</dt>
<dd>
<p>We rewrite the old URL to the new one internally via the
following rule:</p>
<div class="example"><pre>
RewriteEngine on
RewriteRule ^<strong>/old</strong>\.html$ <strong>/new</strong>.html [PT]
</pre></div>
</dd>
</dl>
<div class="section">
<h2><a name="old-to-new-extern" id="old-to-new-extern">Rewriting From Old to New (external)</a></h2>
<dl>
<dt>Description:</dt>
<dd>
<p>Assume again that we have recently renamed the page
to provide the old URL for backward compatibility. But this
time we want that the users of the old URL get hinted to
the new one, i.e. their browsers Location field should
change, too.</p>
</dd>
<dt>Solution:</dt>
<dd>
<p>We force a HTTP redirect to the new URL which leads to a
change of the browsers and thus the users view:</p>
<div class="example"><pre>
RewriteEngine on
RewriteRule ^<strong>/foo</strong>\.html$ <strong>bar</strong>.html [<strong>R</strong>]
</pre></div>
</dd>
<dt>Discussion</dt>
<dd>
<p>In this example, as contrasted to the <a href="#old-to-new-intern">internal</a> example above, we can simply
use the Redirect directive. mod_rewrite was used in that earlier
example in order to hide the redirect from the client:</p>
<div class="example"><p><code>
</code></p></div>
</dd>
</dl>
<div class="section">
<h2><a name="static-to-dynamic" id="static-to-dynamic">From Static to Dynamic</a></h2>
<dl>
<dt>Description:</dt>
<dd>
<p>How can we transform a static page
</dd>
<dt>Solution:</dt>
<dd>
<p>We just rewrite the URL to the CGI-script and force the
handler to be <strong>cgi-script</strong> so that it is
executed as a CGI program.
internally leads to the invocation of
<div class="example"><pre>
RewriteEngine on
RewriteBase /~quux/
RewriteRule ^foo\.<strong>html</strong>$ foo.<strong>cgi</strong> [H=<strong>cgi-script</strong>]
</pre></div>
</dd>
</dl>
<div class="section">
<h2><a name="backward-compatibility" id="backward-compatibility">Backward Compatibility for file extension change</a></h2>
<dl>
<dt>Description:</dt>
<dd>
<p>How can we make URLs backward compatible (still
bunch of <code>.html</code> files to <code>.php</code>?</p>
</dd>
<dt>Solution:</dt>
<dd>
<p>We rewrite the name to its basename and test for
existence of the new extension. If it exists, we take
that name, else we rewrite the URL to its original state.</p>
<div class="example"><pre>
# backward compatibility ruleset for
# rewriting document.html to document.php
# when and only when document.php exists
RewriteEngine on
RewriteCond $1.php -f
RewriteCond $1.html !-f
RewriteRule ^(.*).html$ $1.php
</pre></div>
</dd>
<dt>Discussion</dt>
<dd>
<p>This example uses an often-overlooked feature of mod_rewrite,
by taking advantage of the order of execution of the ruleset. In
particular, mod_rewrite evaluates the left-hand-side of the
RewriteRule before it evaluates the RewriteCond directives.
Consequently, $1 is already defined by the time the RewriteRule
directives are evaluated. This allows us to test for the existence
</dd>
</dl>
<div class="section">
<h2><a name="canonicalhost" id="canonicalhost">Canonical Hostnames</a></h2>
<dl>
<dt>Description:</dt>
<dd>The goal of this rule is to force the use of a particular
hostname, in preference to other hostnames which may be used to
reach the same site. For example, if you wish to force the use
following recipe.</dd>
<dt>Solution:</dt>
<dd>
<p>For sites running on a port other than 80:</p>
<div class="example"><pre>
RewriteCond %{HTTP_HOST} !^www\.example\.com [NC]
RewriteCond %{HTTP_HOST} !^$
RewriteCond %{SERVER_PORT} !^80$
RewriteRule ^/?(.*) http://www.example.com:%{SERVER_PORT}/$1 [L,R,NE]
</pre></div>
<p>And for a site running on port 80</p>
<div class="example"><pre>
RewriteCond %{HTTP_HOST} !^www\.example\.com [NC]
RewriteCond %{HTTP_HOST} !^$
RewriteRule ^/?(.*) http://www.example.com/$1 [L,R,NE]
</pre></div>
<p>
If you wanted to do this generically for all domain names - that
recipe:</p>
<div class="example"><pre>
RewriteCond %{HTTP_HOST} !^www\. [NC]
RewriteCond %{HTTP_HOST} !^$
RewriteRule ^/?(.*) http://www.%{HTTP_HOST}/$1 [L,R,NE]
</pre></div>
<p>These rulesets will work either in your main server configuration
file, or in a <code>.htaccess</code> file placed in the <code class="directive"><a href="/mod/core.html#documentroot">DocumentRoot</a></code> of the server.</p>
</dd>
</dl>
<div class="section">
<h2><a name="multipledirs" id="multipledirs">Search for pages in more than one directory</a></h2>
<dl>
<dt>Description:</dt>
<dd>
<p>A particular resource might exist in one of several places, and
we want to look in those places for the resource when it is
requested. Perhaps we've recently rearranged our directory
structure, dividing content into several locations.</p>
</dd>
<dt>Solution:</dt>
<dd>
<p>The following ruleset searches in two directories to find the
resource, and, if not finding it in either place, will attempt to
just serve it out of the location requested.</p>
<div class="example"><pre>
RewriteEngine on
# first try to find it in dir1/...
# ...and if found stop and be happy:
RewriteCond %{DOCUMENT_ROOT}/<strong>dir1</strong>/%{REQUEST_URI} -f
RewriteRule ^(.+) %{DOCUMENT_ROOT}/<strong>dir1</strong>/$1 [L]
# second try to find it in dir2/...
# ...and if found stop and be happy:
RewriteCond %{DOCUMENT_ROOT}/<strong>dir2</strong>/%{REQUEST_URI} -f
RewriteRule ^(.+) %{DOCUMENT_ROOT}/<strong>dir2</strong>/$1 [L]
# else go on for other Alias or ScriptAlias directives,
# etc.
RewriteRule ^(.+) - [PT]
</pre></div>
</dd>
</dl>
</div></div>
<div class="bottomlang">
<p><span>Available Languages: </span><a href="/en/rewrite/remapping.html" title="English"> en </a></p>
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