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<title>Configuration Sections - 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>
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<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></div><div id="page-content"><div id="preamble"><h1>Configuration Sections</h1>
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<p><span>Available Languages: </span><a href="/en/sections.html" title="English"> en </a> |
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entire server, or they may be restricted to apply only to particular
directories, files, hosts, or URLs. This document describes how to
use configuration section containers or <code>.htaccess</code> files
to change the scope of other configuration directives.</p>
</div>
<div id="quickview"><ul id="toc"><li><img alt="" src="/images/down.gif" /> <a href="#types">Types of Configuration Section Containers</a></li>
<li><img alt="" src="/images/down.gif" /> <a href="#whatwhere">What Directives are Allowed?</a></li>
</ul></div>
<div class="section">
<h2><a name="types" id="types">Types of Configuration Section Containers</a></h2>
<table class="related"><tr><th>Related Modules</th><th>Related Directives</th></tr><tr><td><ul><li><code class="module"><a href="/mod/core.html">core</a></code></li><li><code class="module"><a href="/mod/mod_version.html">mod_version</a></code></li><li><code class="module"><a href="/mod/mod_proxy.html">mod_proxy</a></code></li></ul></td><td><ul><li><code class="directive"><a href="/mod/core.html#directory"><Directory></a></code></li><li><code class="directive"><a href="/mod/core.html#directorymatch"><DirectoryMatch></a></code></li><li><code class="directive"><a href="/mod/core.html#files"><Files></a></code></li><li><code class="directive"><a href="/mod/core.html#filesmatch"><FilesMatch></a></code></li><li><code class="directive"><a href="/mod/core.html#ifdefine"><IfDefine></a></code></li><li><code class="directive"><a href="/mod/core.html#ifmodule"><IfModule></a></code></li><li><code class="directive"><a href="/mod/mod_version.html#ifversion"><IfVersion></a></code></li><li><code class="directive"><a href="/mod/core.html#location"><Location></a></code></li><li><code class="directive"><a href="/mod/core.html#locationmatch"><LocationMatch></a></code></li><li><code class="directive"><a href="/mod/mod_proxy.html#proxy"><Proxy></a></code></li><li><code class="directive"><a href="/mod/mod_proxy.html#proxymatch"><ProxyMatch></a></code></li><li><code class="directive"><a href="/mod/core.html#virtualhost"><VirtualHost></a></code></li></ul></td></tr></table>
<p>There are two basic types of containers. Most containers are
evaluated for each request. The enclosed directives are applied only
for those requests that match the containers. The <code class="directive"><a href="/mod/core.html#ifdefine"><IfDefine></a></code>, <code class="directive"><a href="/mod/core.html#ifmodule"><IfModule></a></code>, and
containers, on the other hand, are evaluated only at server startup
and restart. If their conditions are true at startup, then the
enclosed directives will apply to all requests. If the conditions are
not true, the enclosed directives will be ignored.</p>
<p>The <code class="directive"><a href="/mod/core.html#ifdefine"><IfDefine></a></code> directive
encloses directives that will only be applied if an appropriate
parameter is defined on the <code class="program"><a href="/programs/httpd.html">httpd</a></code> command line. For example,
with the following configuration, all requests will be redirected
to another site only if the server is started using
<code>httpd -DClosedForNow</code>:</p>
<div class="example"><p><code>
<IfDefine ClosedForNow><br />
Redirect / http://otherserver.example.com/<br />
</IfDefine>
</code></p></div>
directive is very similar, except it encloses directives that will
only be applied if a particular module is available in the server.
The module must either be statically compiled in the server, or it
must be dynamically compiled and its <code class="directive"><a href="/mod/mod_so.html#loadmodule">LoadModule</a></code> line must be earlier in the
configuration file. This directive should only be used if you need
your configuration file to work whether or not certain modules are
installed. It should not be used to enclose directives that you want
to work all the time, because it can suppress useful error messages
about missing modules.</p>
<p>In the following example, the <code class="directive"><a href="/mod/mod_mime_magic.html#mimemagicfiles">MimeMagicFiles</a></code> directive will be
applied only if <code class="module"><a href="/mod/mod_mime_magic.html">mod_mime_magic</a></code> is available.</p>
<div class="example"><p><code>
<IfModule mod_mime_magic.c><br />
</IfModule>
</code></p></div>
<p>The <code class="directive"><a href="/mod/mod_version.html#ifversion"><IfVersion></a></code>
directive is very similar to <code class="directive"><a href="/mod/core.html#ifdefine"><IfDefine></a></code> and <code class="directive"><a href="/mod/core.html#ifmodule"><IfModule></a></code>, except it encloses directives that will
only be applied if a particular version of the server is executing. This
module is designed for the use in test suites and large networks which have to
deal with different httpd versions and different configurations.</p>
<div class="example"><p><code>
<IfVersion >= 2.1><br />
<span class="indent">
# this happens only in versions greater or<br />
# equal 2.1.0.<br />
</span>
</IfVersion>
</code></p></div>
can apply negative conditions by preceding their test with "!".
Also, these sections can be nested to achieve more complex
restrictions.</p>
<div class="section">
<h2><a name="file-and-web" id="file-and-web">Filesystem and Webspace</a></h2>
<p>The most commonly used configuration section containers are the
ones that change the configuration of particular places in the
filesystem or webspace. First, it is important to understand the
difference between the two. The filesystem is the view of your disks
as seen by your operating system. For example, in a default install,
the Windows filesystem. (Note that forward slashes should always be
used as the path separator in Apache, even for Windows.) In contrast,
the webspace is the view of your site as delivered by the web server
and seen by the client. So the path <code>/dir/</code> in the
webspace corresponds to the path
default Apache install on Unix. The webspace need not map directly to
the filesystem, since webpages may be generated dynamically
from databases or other locations.</p>
<h3><a name="filesystem" id="filesystem">Filesystem Containers</a></h3>
directives, along with their <a class="glossarylink" href="/glossary.html#regex" title="see glossary">regex</a>
counterparts, apply directives to
parts of the filesystem. Directives enclosed in a <code class="directive"><a href="/mod/core.html#directory"><Directory></a></code> section apply to
the named filesystem directory and all subdirectories of that
directory. The same effect can be obtained using <a href="howto/htaccess.html">.htaccess files</a>. For example, in the
following configuration, directory indexes will be enabled for the
<div class="example"><p><code>
Options +Indexes<br />
</Directory>
</code></p></div>
<p>Directives enclosed in a <code class="directive"><a href="/mod/core.html#files"><Files></a></code> section apply to any file with
the specified name, regardless of what directory it lies in.
So for example, the following configuration directives will,
when placed in the main section of the configuration file,
of where it is found.</p>
<div class="example"><p><code>
<Files private.html><br />
Order allow,deny<br />
Deny from all<br />
</Files>
</code></p></div>
<p>To address files found in a particular part of the filesystem, the
can be combined. For example, the following configuration will deny
directory.</p>
<div class="example"><p><code>
<Files private.html><br />
Order allow,deny<br />
Deny from all<br />
</Files><br />
</Directory>
</code></p></div>
<h3><a name="webspace" id="webspace">Webspace Containers</a></h3>
directive and its <a class="glossarylink" href="/glossary.html#regex" title="see glossary">regex</a> counterpart, on
the other hand, change the
configuration for content in the webspace. For example, the following
configuration prevents access to any URL-path that begins in /private.
In particular, it will apply to requests for
as any other requests starting with the <code>/private</code> string.</p>
<div class="example"><p><code>
<Location /private><br />
Order Allow,Deny<br />
Deny from all<br />
</Location>
</code></p></div>
directive need not have anything to do with the filesystem.
For example, the following example shows how to map a particular
URL to an internal Apache handler provided by <code class="module"><a href="/mod/mod_status.html">mod_status</a></code>.
No file called <code>server-status</code> needs to exist in the
filesystem.</p>
<div class="example"><p><code>
<Location /server-status><br />
SetHandler server-status<br />
</Location>
</code></p></div>
<h3><a name="wildcards" id="wildcards">Wildcards and Regular Expressions</a></h3>
directives can each use shell-style wildcard characters as in
<code>fnmatch</code> from the C standard library. The character "*"
matches any sequence of characters, "?" matches any single character,
and "[<em>seq</em>]" matches any character in <em>seq</em>. The "/"
character will not be matched by any wildcard; it must be specified
explicitly.</p>
<p>If even more flexible matching is required, each
container has a regular expression (regex) counterpart <code class="directive"><a href="/mod/core.html#directorymatch"><DirectoryMatch></a></code>, <code class="directive"><a href="/mod/core.html#filesmatch"><FilesMatch></a></code>, and <code class="directive"><a href="/mod/core.html#locationmatch"><LocationMatch></a></code> that allow
perl-compatible
to be used in choosing the matches. But see the section below on
configuration merging to find out how using regex sections will change
how directives are applied.</p>
<p>A non-regex wildcard section that changes the configuration of
all user directories could look as follows:</p>
<div class="example"><p><code>
<Directory /home/*/public_html><br />
Options Indexes<br />
</Directory>
</code></p></div>
<p>Using regex sections, we can deny access to many types of image files
at once:</p>
<div class="example"><p><code>
<FilesMatch \.(?i:gif|jpe?g|png)$><br />
Order allow,deny<br />
Deny from all<br />
</FilesMatch>
</code></p></div>
<h3><a name="whichwhen" id="whichwhen">What to use When</a></h3>
<p>Choosing between filesystem containers and webspace containers is
actually quite easy. When applying directives to objects that reside
in the filesystem always use <code class="directive"><a href="/mod/core.html#directory"><Directory></a></code> or <code class="directive"><a href="/mod/core.html#files"><Files></a></code>. When applying directives to objects
that do not reside in the filesystem (such as a webpage generated from
a database), use <code class="directive"><a href="/mod/core.html#location"><Location></a></code>.</p>
<p>It is important to never use <code class="directive"><a href="/mod/core.html#location"><Location></a></code> when trying to restrict
access to objects in the filesystem. This is because many
different webspace locations (URLs) could map to the same filesystem
location, allowing your restrictions to be circumvented.
For example, consider the following configuration:</p>
<div class="example"><p><code>
<Location /dir/><br />
Order allow,deny<br />
Deny from all<br />
</Location>
</code></p></div>
<p>This works fine if the request is for
a case-insensitive filesystem? Then your restriction could be easily
circumvented by requesting
<code>http://yoursite.example.com/DIR/</code>. The <code class="directive"><a href="/mod/core.html#directory"><Directory></a></code> directive, in
contrast, will apply to any content served from that location,
regardless of how it is called. (An exception is filesystem links.
The same directory can be placed in more than one part of the
filesystem using symbolic links. The <code class="directive"><a href="/mod/core.html#directory"><Directory></a></code> directive will follow the symbolic
link without resetting the pathname. Therefore, for the highest level
of security, symbolic links should be disabled with the appropriate
<p>If you are, perhaps, thinking that none of this applies to you
because you use a case-sensitive filesystem, remember that there are
many other ways to map multiple webspace locations to the same
filesystem location. Therefore you should always use the filesystem
containers when you can. There is, however, one exception to this
rule. Putting configuration restrictions in a <code><Location
/></code> section is perfectly safe because this section will apply
to all requests regardless of the specific URL.</p>
<div class="section">
<h2><a name="virtualhost" id="virtualhost">Virtual Hosts</a></h2>
container encloses directives that apply to specific hosts.
This is useful when serving multiple hosts from the same machine
with a different configuration for each. For more information,
see the <a href="vhosts/">Virtual Host Documentation</a>.</p>
<div class="section">
<h2><a name="proxy" id="proxy">Proxy</a></h2>
containers apply enclosed configuration directives only
to sites accessed through <code class="module"><a href="/mod/mod_proxy.html">mod_proxy</a></code>'s proxy server
that match the specified URL. For example, the following configuration
will prevent the proxy server from being used to access the
<div class="example"><p><code>
<Proxy http://cnn.com/*><br />
Order allow,deny<br />
Deny from all<br />
</Proxy>
</code></p></div>
<div class="section">
<h2><a name="whatwhere" id="whatwhere">What Directives are Allowed?</a></h2>
<p>To find out what directives are allowed in what types of
configuration sections, check the <a href="mod/directive-dict.html#Context">Context</a> of the directive.
Everything that is allowed in
sections is also syntactically allowed in
sections. There are some exceptions, however:</p>
<ul>
<li>The <code class="directive"><a href="/mod/core.html#allowoverride">AllowOverride</a></code> directive
works only in <code class="directive"><a href="/mod/core.html#directory"><Directory></a></code>
sections.</li>
<li>The <code>FollowSymLinks</code> and
<code>SymLinksIfOwnerMatch</code> <code class="directive"><a href="/mod/core.html#options">Options</a></code> work only in <code class="directive"><a href="/mod/core.html#directory"><Directory></a></code> sections or
<code>.htaccess</code> files.</li>
<li>The <code class="directive"><a href="/mod/core.html#options">Options</a></code> directive cannot
sections.</li>
</ul>
<div class="section">
<h2><a name="mergin" id="mergin">How the sections are merged</a></h2>
<p>The configuration sections are applied in a very particular order.
Since this can have important effects on how configuration directives
are interpreted, it is important to understand how this works.</p>
<p>The order of merging is:</p>
<ol>
<li> <code class="directive"><a href="/mod/core.html#directory"><Directory></a></code> (except regular expressions)
and <code>.htaccess</code> done simultaneously (with
<code>.htaccess</code>, if allowed, overriding
<li><code class="directive"><a href="/mod/core.html#directorymatch"><DirectoryMatch></a></code>
(and <code><Directory ~></code>)</li>
<li><code class="directive"><a href="/mod/core.html#files"><Files></a></code> and <code class="directive"><a href="/mod/core.html#filesmatch"><FilesMatch></a></code> done
simultaneously</li>
and <code class="directive"><a href="/mod/core.html#locationmatch"><LocationMatch></a></code> done simultaneously</li>
</ol>
<p>Apart from <code class="directive"><a href="/mod/core.html#directory"><Directory></a></code>, each group is processed in
the order that they appear in the configuration files. <code class="directive"><a href="/mod/core.html#directory"><Directory></a></code> (group 1 above)
is processed in the order shortest directory component to longest.
be processed before <code><Directory
/var/web/dir/subdir></code>. If multiple <code class="directive"><a href="/mod/core.html#directory"><Directory></a></code> sections apply
to the same directory they are processed in the configuration file
order. Configurations included via the <code class="directive"><a href="/mod/core.html#include">Include</a></code> directive will be treated as if
they were inside the including file at the location of the
<p>Sections inside <code class="directive"><a href="/mod/core.html#virtualhost"><VirtualHost></a></code> sections
are applied <em>after</em> the corresponding sections outside
the virtual host definition. This allows virtual hosts to
override the main server configuration.</p>
<p>When the request is served by <code class="module"><a href="/mod/mod_proxy.html">mod_proxy</a></code>, the
container takes the place of the <code class="directive"><a href="/mod/core.html#directory"><Directory></a></code> container in the processing
order.</p>
<p>Later sections override earlier ones.</p>
<div class="note"><h3>Technical Note</h3>
There is actually a
<code><Location></code>/<code><LocationMatch></code>
sequence performed just before the name translation phase
(where <code>Aliases</code> and <code>DocumentRoots</code>
are used to map URLs to filenames). The results of this
sequence are completely thrown away after the translation has
completed.
</div>
<h3><a name="merge-examples" id="merge-examples">Some Examples</a></h3>
<p>Below is an artificial example to show the order of
merging. Assuming they all apply to the request, the directives in
this example will be applied in the order A > B > C > D >
E.</p>
<div class="example"><p><code>
<Location /><br />
E<br />
</Location><br />
<br />
<Files f.html><br />
D<br />
</Files><br />
<br />
<VirtualHost *><br />
<Directory /a/b><br />
B<br />
</Directory><br />
</VirtualHost><br />
<br />
<DirectoryMatch "^.*b$"><br />
C<br />
</DirectoryMatch><br />
<br />
<Directory /a/b><br />
A<br />
</Directory><br />
<br />
</code></p></div>
<p>For a more concrete example, consider the following. Regardless of
any access restrictions placed in <code class="directive"><a href="/mod/core.html#directory"><Directory></a></code> sections, the <code class="directive"><a href="/mod/core.html#location"><Location></a></code> section will be
evaluated last and will allow unrestricted access to the server. In
other words, order of merging is important, so be careful!</p>
<div class="example"><p><code>
<Location /><br />
Order deny,allow<br />
Allow from all<br />
</Location><br />
<br />
# Woops! This <Directory> section will have no effect<br />
<Directory /><br />
Order allow,deny<br />
Allow from all<br />
Deny from badguy.example.com<br />
</Directory>
</code></p></div>
</div></div>
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