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+<?xml version="1.0" encoding="UTF-8"?>
+<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Strict//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-strict.dtd">
+<html xmlns="http://www.w3.org/1999/xhtml" lang="en" xml:lang="en"><head>
+<meta content="text/html; charset=UTF-8" http-equiv="Content-Type" />
+<!--
+ XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX
+ This file is generated from xml source: DO NOT EDIT
+ XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX
+ -->
+<title>Configuration Sections - Apache HTTP Server Version 2.4</title>
+<link href="./style/css/manual.css" rel="stylesheet" media="all" type="text/css" title="Main stylesheet" />
+<link href="./style/css/manual-loose-100pc.css" rel="alternate stylesheet" media="all" type="text/css" title="No Sidebar - Default font size" />
+<link href="./style/css/manual-print.css" rel="stylesheet" media="print" type="text/css" /><link rel="stylesheet" type="text/css" href="./style/css/prettify.css" />
+<script src="./style/scripts/prettify.min.js" type="text/javascript">
+</script>
+
+<link href="./images/favicon.ico" rel="shortcut icon" /></head>
+<body id="manual-page"><div id="page-header">
+<p class="menu"><a href="./mod/">Modules</a> | <a href="./mod/directives.html">Directives</a> | <a href="http://wiki.apache.org/httpd/FAQ">FAQ</a> | <a href="./glossary.html">Glossary</a> | <a href="./sitemap.html">Sitemap</a></p>
+<p class="apache">Apache HTTP Server Version 2.4</p>
+<img alt="" src="./images/feather.png" /></div>
+<div class="up"><a href="./"><img title="&lt;-" alt="&lt;-" src="./images/left.gif" /></a></div>
+<div id="path">
+<a href="http://www.apache.org/">Apache</a> &gt; <a href="http://httpd.apache.org/">HTTP Server</a> &gt; <a href="http://httpd.apache.org/docs/">Documentation</a> &gt; <a href="./">Version 2.4</a></div><div id="page-content"><div id="preamble"><h1>Configuration Sections</h1>
+<div class="toplang">
+<p><span>Available Languages: </span><a href="./en/sections.html" title="English">&nbsp;en&nbsp;</a> |
+<a href="./fr/sections.html" hreflang="fr" rel="alternate" title="Français">&nbsp;fr&nbsp;</a> |
+<a href="./ja/sections.html" hreflang="ja" rel="alternate" title="Japanese">&nbsp;ja&nbsp;</a> |
+<a href="./ko/sections.html" hreflang="ko" rel="alternate" title="Korean">&nbsp;ko&nbsp;</a> |
+<a href="./tr/sections.html" hreflang="tr" rel="alternate" title="Türkçe">&nbsp;tr&nbsp;</a></p>
+</div>
+ <p>Directives in the <a href="configuring.html">configuration files</a> may apply to the
+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"><a href="https://www.apache.org/foundation/contributing.html" class="badge"><img src="https://www.apache.org/images/SupportApache-small.png" alt="Support Apache!" /></a><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="#file-and-web">Filesystem, Webspace, and Boolean Expressions</a></li>
+<li><img alt="" src="./images/down.gif" /> <a href="#virtualhost">Virtual Hosts</a></li>
+<li><img alt="" src="./images/down.gif" /> <a href="#proxy">Proxy</a></li>
+<li><img alt="" src="./images/down.gif" /> <a href="#whatwhere">What Directives are Allowed?</a></li>
+<li><img alt="" src="./images/down.gif" /> <a href="#merging">How the sections are merged</a></li>
+</ul><h3>See also</h3><ul class="seealso"><li><a href="#comments_section">Comments</a></li></ul></div>
+<div class="top"><a href="#page-header"><img alt="top" src="./images/up.gif" /></a></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">&lt;Directory&gt;</a></code></li><li><code class="directive"><a href="./mod/core.html#directorymatch">&lt;DirectoryMatch&gt;</a></code></li><li><code class="directive"><a href="./mod/core.html#files">&lt;Files&gt;</a></code></li><li><code class="directive"><a href="./mod/core.html#filesmatch">&lt;FilesMatch&gt;</a></code></li><li><code class="directive"><a href="./mod/core.html#if">&lt;If&gt;</a></code></li><li><code class="directive"><a href="./mod/core.html#ifdefine">&lt;IfDefine&gt;</a></code></li><li><code class="directive"><a href="./mod/core.html#ifmodule">&lt;IfModule&gt;</a></code></li><li><code class="directive"><a href="./mod/mod_version.html#ifversion">&lt;IfVersion&gt;</a></code></li><li><code class="directive"><a href="./mod/core.html#location">&lt;Location&gt;</a></code></li><li><code class="directive"><a href="./mod/core.html#locationmatch">&lt;LocationMatch&gt;</a></code></li><li><code class="directive"><a href="./mod/mod_md.html#mdomainsetsection">&lt;MDomainSet&gt;</a></code></li><li><code class="directive"><a href="./mod/mod_proxy.html#proxy">&lt;Proxy&gt;</a></code></li><li><code class="directive"><a href="./mod/mod_proxy.html#proxymatch">&lt;ProxyMatch&gt;</a></code></li><li><code class="directive"><a href="./mod/core.html#virtualhost">&lt;VirtualHost&gt;</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">&lt;IfDefine&gt;</a></code>, <code class="directive"><a href="./mod/core.html#ifmodule">&lt;IfModule&gt;</a></code>, and
+<code class="directive"><a href="./mod/mod_version.html#ifversion">&lt;IfVersion&gt;</a></code>
+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">&lt;IfDefine&gt;</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>
+
+<pre class="prettyprint lang-config">&lt;IfDefine ClosedForNow&gt;
+ Redirect "/" "http://otherserver.example.com/"
+&lt;/IfDefine&gt;</pre>
+
+
+<p>The <code class="directive"><a href="./mod/core.html#ifmodule">&lt;IfModule&gt;</a></code>
+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#mimemagicfile">MimeMagicFile</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>
+
+<pre class="prettyprint lang-config">&lt;IfModule mod_mime_magic.c&gt;
+ MimeMagicFile "conf/magic"
+&lt;/IfModule&gt;</pre>
+
+
+<p>The <code class="directive"><a href="./mod/mod_version.html#ifversion">&lt;IfVersion&gt;</a></code>
+directive is very similar to <code class="directive"><a href="./mod/core.html#ifdefine">&lt;IfDefine&gt;</a></code> and <code class="directive"><a href="./mod/core.html#ifmodule">&lt;IfModule&gt;</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>
+
+<pre class="prettyprint lang-config">&lt;IfVersion &gt;= 2.4&gt;
+ # this happens only in versions greater or
+ # equal 2.4.0.
+&lt;/IfVersion&gt;</pre>
+
+
+<p><code class="directive"><a href="./mod/core.html#ifdefine">&lt;IfDefine&gt;</a></code>,
+<code class="directive"><a href="./mod/core.html#ifmodule">&lt;IfModule&gt;</a></code>, and the
+<code class="directive"><a href="./mod/mod_version.html#ifversion">&lt;IfVersion&gt;</a></code>
+can apply negative conditions by preceding their test with "!".
+Also, these sections can be nested to achieve more complex
+restrictions.</p>
+</div><div class="top"><a href="#page-header"><img alt="top" src="./images/up.gif" /></a></div>
+<div class="section">
+<h2><a name="file-and-web" id="file-and-web">Filesystem, Webspace, and Boolean Expressions</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,
+Apache httpd resides at <code>/usr/local/apache2</code> in the Unix
+filesystem or <code>"c:/Program Files/Apache Group/Apache2"</code> in
+the Windows filesystem. (Note that forward slashes should always be
+used as the path separator in Apache httpd configuration files, 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
+<code>/usr/local/apache2/htdocs/dir/</code> in the filesystem of a
+default Apache httpd 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>
+
+<p>The <code class="directive"><a href="./mod/core.html#directory">&lt;Directory&gt;</a></code>
+and <code class="directive"><a href="./mod/core.html#files">&lt;Files&gt;</a></code>
+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">&lt;Directory&gt;</a></code> section apply to
+the named filesystem directory and all subdirectories of that
+directory (as well as the files in those directories).
+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
+<code>/var/web/dir1</code> directory and all subdirectories.</p>
+
+<pre class="prettyprint lang-config">&lt;Directory "/var/web/dir1"&gt;
+ Options +Indexes
+&lt;/Directory&gt;</pre>
+
+
+<p>Directives enclosed in a <code class="directive"><a href="./mod/core.html#files">&lt;Files&gt;</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,
+deny access to any file named <code>private.html</code> regardless
+of where it is found.</p>
+
+<pre class="prettyprint lang-config">&lt;Files "private.html"&gt;
+ Require all denied
+&lt;/Files&gt;</pre>
+
+
+<p>To address files found in a particular part of the filesystem, the
+<code class="directive"><a href="./mod/core.html#files">&lt;Files&gt;</a></code> and
+<code class="directive"><a href="./mod/core.html#directory">&lt;Directory&gt;</a></code> sections
+can be combined. For example, the following configuration will deny
+access to <code>/var/web/dir1/private.html</code>,
+<code>/var/web/dir1/subdir2/private.html</code>,
+<code>/var/web/dir1/subdir3/private.html</code>, and any other instance
+of <code>private.html</code> found under the <code>/var/web/dir1/</code>
+directory.</p>
+
+<pre class="prettyprint lang-config">&lt;Directory "/var/web/dir1"&gt;
+ &lt;Files "private.html"&gt;
+ Require all denied
+ &lt;/Files&gt;
+&lt;/Directory&gt;</pre>
+
+
+
+<h3><a name="webspace" id="webspace">Webspace Containers</a></h3>
+
+<p>The <code class="directive"><a href="./mod/core.html#location">&lt;Location&gt;</a></code>
+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
+<code>http://yoursite.example.com/private</code>,
+<code>http://yoursite.example.com/private123</code>, and
+<code>http://yoursite.example.com/private/dir/file.html</code> as well
+as any other requests starting with the <code>/private</code> string.</p>
+
+<pre class="prettyprint lang-config">&lt;LocationMatch "^/private"&gt;
+ Require all denied
+&lt;/LocationMatch&gt;</pre>
+
+
+<p>The <code class="directive"><a href="./mod/core.html#location">&lt;Location&gt;</a></code>
+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 HTTP Server 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>
+
+<pre class="prettyprint lang-config">&lt;Location "/server-status"&gt;
+ SetHandler server-status
+&lt;/Location&gt;</pre>
+
+
+
+<h3><a name="overlapping-webspace" id="overlapping-webspace">Overlapping Webspace</a></h3>
+<p>In order to have two overlapping URLs one has to consider the order in which
+certain sections or directives are evaluated. For
+<code class="directive"><a href="./mod/core.html#location">&lt;Location&gt;</a></code> this would be:</p>
+<pre class="prettyprint lang-config">&lt;Location "/foo"&gt;
+&lt;/Location&gt;
+&lt;Location "/foo/bar"&gt;
+&lt;/Location&gt;</pre>
+
+<p><code class="directive"><a href="./mod/mod_alias.html#alias">&lt;Alias&gt;</a></code>es on the other hand,
+are mapped vice-versa:</p>
+<pre class="prettyprint lang-config">Alias "/foo/bar" "/srv/www/uncommon/bar"
+Alias "/foo" "/srv/www/common/foo"</pre>
+
+<p>The same is true for the <code class="directive"><a href="./mod/mod_proxy.html#proxypass">ProxyPass</a></code>
+directives:</p>
+<pre class="prettyprint lang-config">ProxyPass "/special-area" "http://special.example.com" smax=5 max=10
+ProxyPass "/" "balancer://mycluster/" stickysession=JSESSIONID|jsessionid nofailover=On</pre>
+
+
+
+<h3><a name="wildcards" id="wildcards">Wildcards and Regular Expressions</a></h3>
+
+<p>The <code class="directive"><a href="./mod/core.html#directory">&lt;Directory&gt;</a></code>,
+<code class="directive"><a href="./mod/core.html#files">&lt;Files&gt;</a></code>, and
+<code class="directive"><a href="./mod/core.html#location">&lt;Location&gt;</a></code>
+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">&lt;DirectoryMatch&gt;</a></code>, <code class="directive"><a href="./mod/core.html#filesmatch">&lt;FilesMatch&gt;</a></code>, and <code class="directive"><a href="./mod/core.html#locationmatch">&lt;LocationMatch&gt;</a></code> that allow
+perl-compatible
+<a class="glossarylink" href="./glossary.html#regex" title="see glossary">regular expressions</a>
+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>
+
+<pre class="prettyprint lang-config">&lt;Directory "/home/*/public_html"&gt;
+ Options Indexes
+&lt;/Directory&gt;</pre>
+
+
+<p>Using regex sections, we can deny access to many types of image files
+at once:</p>
+<pre class="prettyprint lang-config">&lt;FilesMatch "\.(?i:gif|jpe?g|png)$"&gt;
+ Require all denied
+&lt;/FilesMatch&gt;</pre>
+
+
+<p>Regular expressions containing <strong>named groups and
+backreferences</strong> are added to the environment with the
+corresponding name in uppercase. This allows elements of filename paths
+and URLs to be referenced from within <a href="expr.html">expressions</a>
+and modules like <code class="module"><a href="./mod/mod_rewrite.html">mod_rewrite</a></code>.</p>
+
+<pre class="prettyprint lang-config">&lt;DirectoryMatch "^/var/www/combined/(?&lt;SITENAME&gt;[^/]+)"&gt;
+ Require ldap-group "cn=%{env:MATCH_SITENAME},ou=combined,o=Example"
+&lt;/DirectoryMatch&gt;</pre>
+
+
+
+
+<h3><a name="expressions" id="expressions">Boolean expressions</a></h3>
+<p>The <code class="directive"><a href="./mod/core.html#if">&lt;If&gt;</a></code>
+directive change the configuration depending on a condition which can be
+expressed by a boolean expression. For example, the following configuration
+denies access if the HTTP Referer header does not start with
+"http://www.example.com/".</p>
+<pre class="prettyprint lang-config">&lt;If "!(%{HTTP_REFERER} -strmatch 'http://www.example.com/*')"&gt;
+ Require all denied
+&lt;/If&gt;</pre>
+
+
+
+
+<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">&lt;Directory&gt;</a></code> or <code class="directive"><a href="./mod/core.html#files">&lt;Files&gt;</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">&lt;Location&gt;</a></code>.</p>
+
+<p>It is important to never use <code class="directive"><a href="./mod/core.html#location">&lt;Location&gt;</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>
+
+<pre class="prettyprint lang-config">&lt;Location "/dir/"&gt;
+ Require all denied
+&lt;/Location&gt;</pre>
+
+
+<p>This works fine if the request is for
+<code>http://yoursite.example.com/dir/</code>. But what if you are on
+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">&lt;Directory&gt;</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">&lt;Directory&gt;</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
+<code class="directive"><a href="./mod/core.html#options">Options</a></code> directive.)</p>
+
+<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>&lt;Location
+"/"&gt;</code> section is perfectly safe because this section will apply
+to all requests regardless of the specific URL.</p>
+
+
+<h3><a name="nesting" id="nesting">Nesting of sections</a></h3>
+
+<p>Some section types can be nested inside other section types. On the one
+hand, <code class="directive"><a href="./mod/core.html#files">&lt;Files&gt;</a></code> can be used
+inside <code class="directive"><a href="./mod/core.html#directory">&lt;Directory&gt;</a></code>. On
+the other hand, <code class="directive"><a href="./mod/core.html#if">&lt;If&gt;</a></code> can
+be used inside <code class="directive"><a href="./mod/core.html#directory">&lt;Directory&gt;</a></code>,
+<code class="directive"><a href="./mod/core.html#location">&lt;Location&gt;</a></code>, and <code class="directive"><a href="./mod/core.html#files">&lt;Files&gt;</a></code> sections (but not inside another
+<code class="directive"><a href="./mod/core.html#if">&lt;If&gt;</a></code>). The regex
+counterparts of the named section behave identically.</p>
+
+<p>Nested sections are merged after non-nested sections of the same type.</p>
+
+
+
+</div><div class="top"><a href="#page-header"><img alt="top" src="./images/up.gif" /></a></div>
+<div class="section">
+<h2><a name="virtualhost" id="virtualhost">Virtual Hosts</a></h2>
+
+<p>The <code class="directive"><a href="./mod/core.html#virtualhost">&lt;VirtualHost&gt;</a></code>
+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><div class="top"><a href="#page-header"><img alt="top" src="./images/up.gif" /></a></div>
+<div class="section">
+<h2><a name="proxy" id="proxy">Proxy</a></h2>
+
+<p>The <code class="directive"><a href="./mod/mod_proxy.html#proxy">&lt;Proxy&gt;</a></code>
+and <code class="directive"><a href="./mod/mod_proxy.html#proxymatch">&lt;ProxyMatch&gt;</a></code>
+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 allow only a subset of clients to access the
+<code>www.example.com</code> website using the proxy server:</p>
+
+<pre class="prettyprint lang-config">&lt;Proxy "http://www.example.com/*"&gt;
+ Require host yournetwork.example.com
+&lt;/Proxy&gt;</pre>
+
+</div><div class="top"><a href="#page-header"><img alt="top" src="./images/up.gif" /></a></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
+<code class="directive"><a href="./mod/core.html#directory">&lt;Directory&gt;</a></code>
+sections is also syntactically allowed in
+<code class="directive"><a href="./mod/core.html#directorymatch">&lt;DirectoryMatch&gt;</a></code>,
+<code class="directive"><a href="./mod/core.html#files">&lt;Files&gt;</a></code>,
+<code class="directive"><a href="./mod/core.html#filesmatch">&lt;FilesMatch&gt;</a></code>,
+<code class="directive"><a href="./mod/core.html#location">&lt;Location&gt;</a></code>,
+<code class="directive"><a href="./mod/core.html#locationmatch">&lt;LocationMatch&gt;</a></code>,
+<code class="directive"><a href="./mod/mod_proxy.html#proxy">&lt;Proxy&gt;</a></code>,
+and <code class="directive"><a href="./mod/mod_proxy.html#proxymatch">&lt;ProxyMatch&gt;</a></code>
+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">&lt;Directory&gt;</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">&lt;Directory&gt;</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
+be used in <code class="directive"><a href="./mod/core.html#files">&lt;Files&gt;</a></code>
+and <code class="directive"><a href="./mod/core.html#filesmatch">&lt;FilesMatch&gt;</a></code>
+sections.</li>
+</ul>
+</div><div class="top"><a href="#page-header"><img alt="top" src="./images/up.gif" /></a></div>
+<div class="section">
+<h2><a name="merging" id="merging">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">&lt;Directory&gt;</a></code> (except regular expressions)
+ and <code>.htaccess</code> done simultaneously (with
+ <code>.htaccess</code>, if allowed, overriding
+ <code class="directive"><a href="./mod/core.html#directory">&lt;Directory&gt;</a></code>)</li>
+
+ <li><code class="directive"><a href="./mod/core.html#directorymatch">&lt;DirectoryMatch&gt;</a></code>
+ (and <code>&lt;Directory "~"&gt;</code>)</li>
+
+ <li><code class="directive"><a href="./mod/core.html#files">&lt;Files&gt;</a></code> and <code class="directive"><a href="./mod/core.html#filesmatch">&lt;FilesMatch&gt;</a></code> done
+ simultaneously</li>
+
+ <li><code class="directive"><a href="./mod/core.html#location">&lt;Location&gt;</a></code>
+ and <code class="directive"><a href="./mod/core.html#locationmatch">&lt;LocationMatch&gt;</a></code> done simultaneously</li>
+
+ <li><code class="directive"><a href="./mod/core.html#if">&lt;If&gt;</a></code> sections, even when
+ they are enclosed in any of the preceding contexts.
+ </li>
+
+ </ol>
+
+ <p>Some important remarks:</p>
+ <ul>
+ <li>Apart from <code class="directive"><a href="./mod/core.html#directory">&lt;Directory&gt;</a></code>, within each group the sections are
+ processed in the order they appear in the configuration files.
+ For example, a request for <em>/foo/bar</em> will match
+ <code>&lt;Location "/foo/bar"&gt;</code> and
+ <code>&lt;Location "/foo"&gt;</code> (group 4 in this case):
+ both sections will be evaluated
+ but in the order they appear in the configuration files.</li>
+ <li><code class="directive"><a href="./mod/core.html#directory">&lt;Directory&gt;</a></code>
+ (group 1 above) is processed in the order shortest directory
+ component to longest. For example,
+ <code>&lt;Directory "/var/web/dir"&gt;</code> will be processed before
+ <code>&lt;Directory "/var/web/dir/subdir"&gt;</code>.</li>
+ <li>If multiple <code class="directive"><a href="./mod/core.html#directory">&lt;Directory&gt;</a></code> sections apply
+ to the same directory they are processed in the configuration file
+ order.</li>
+ <li>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
+ <code class="directive"><a href="./mod/core.html#include">Include</a></code> directive.</li>
+ <li>Sections inside <code class="directive"><a href="./mod/core.html#virtualhost">&lt;VirtualHost&gt;</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.</li>
+ <li>When the request is served by <code class="module"><a href="./mod/mod_proxy.html">mod_proxy</a></code>, the
+ <code class="directive"><a href="./mod/mod_proxy.html#proxy">&lt;Proxy&gt;</a></code>
+ container takes the place of the <code class="directive"><a href="./mod/core.html#directory">&lt;Directory&gt;</a></code> container in the processing
+ order.</li>
+ <li> Caution should be exercised when mixing related configuration
+ directives inside and outside of <code class="directive"><a href="./mod/core.html#if">&lt;If&gt;</a></code> because of the effect on merging order. Explicit use
+ of <code class="directive"><a href="./mod/core.html#else">&lt;Else&gt;</a></code> can help.
+ </li>
+ <li> When <code class="directive"><a href="./mod/core.html#if">&lt;If&gt;</a></code> is
+ used in <code>.htaccess</code>, the enclosed directives in a parent
+ directory will be merged <em>after</em> non-enclosed directives in a
+ subdirectory.</li>
+ </ul>
+
+ <div class="note"><h3>Technical Note</h3>
+ There is actually a
+ <code>&lt;Location&gt;</code>/<code>&lt;LocationMatch&gt;</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="relationship-module-configuration" id="relationship-module-configuration">Relationship between modules and configuration sections</a></h3>
+ <p>One question that often arises after reading how configuration sections are
+ merged is related to how and when directives of specific modules like <code class="module"><a href="./mod/mod_rewrite.html">mod_rewrite</a></code>
+ are processed. The answer is not trivial and needs a bit of background.
+ Each httpd module manages its own configuration, and each of its directives in httpd.conf specify one piece
+ of configuration in a particular context. httpd does not execute a command as it is read.</p>
+ <p>At runtime, the core of httpd iterates over the defined configuration sections in the order
+ described above to determine which ones apply to the current request. When the first section matches,
+ it is considered the current configuration for this request. If a subsequent section matches too,
+ then each module with a directive in either of the sections is given a chance to merge its configuration between the two sections. The result is a third configuration, and the process goes on until all the configuration sections
+ are evaluated.</p>
+ <p>After the above step, the "real" processing of the HTTP request begins: each module has a chance to run
+ and perform whatever tasks they like. They can retrieve their own final merged configuration from the core
+ of the httpd to determine how they should act.</p>
+ <p>An example can help to visualize the whole process. The following configuration uses the
+ <code class="directive"><a href="./mod/mod_headers.html#header">Header</a></code> directive of <code class="module"><a href="./mod/mod_headers.html">mod_headers</a></code> to set
+ a specific HTTP header. What value will httpd set in the <code>CustomHeaderName</code> header for a request to
+ <code>/example/index.html</code> ?
+ </p>
+ <pre class="prettyprint lang-config">&lt;Directory "/"&gt;
+ Header set CustomHeaderName one
+ &lt;FilesMatch ".*"&gt;
+ Header set CustomHeaderName three
+ &lt;/FilesMatch&gt;
+&lt;/Directory&gt;
+
+&lt;Directory "/example"&gt;
+ Header set CustomHeaderName two
+&lt;/Directory&gt;</pre>
+
+ <ul>
+ <li><code class="directive">Directory</code> "/" matches and an initial configuration to set the <code>CustomHeaderName</code> header with the value <code>one</code> is created.</li>
+ <li><code class="directive">Directory</code> "/example" matches, and since <code class="module"><a href="./mod/mod_headers.html">mod_headers</a></code> specifies in its code to override in case of a merge, a new configuration is created to set the <code>CustomHeaderName</code> header with the value <code>two</code>.</li>
+ <li><code class="directive">FilesMatch</code> ".*" matches and another merge opportunity arises, causing the <code>CustomHeaderName</code> header to be set with the value <code>three</code>.</li>
+ <li>Eventually during the next steps of the HTTP request processing <code class="module"><a href="./mod/mod_headers.html">mod_headers</a></code> will be called and it will receive the configuration to set the <code>CustomHeaderName</code> header with the value <code>three</code>. <code class="module"><a href="./mod/mod_headers.html">mod_headers</a></code> normally uses this configuration to perform its job, namely setting the foo header. This does not mean that a module can't perform a more complex action like discarding directives because not needed or deprecated, etc..</li>
+ </ul>
+
+ <p>This is true for .htaccess too since they have the same priority as <code class="directive">Directory</code> in the merge order. The important concept to understand is that configuration sections like <code class="directive">Directory</code> and <code class="directive">FilesMatch</code> are not comparable to module specific directives like <code class="directive"><a href="./mod/mod_headers.html#header">Header</a></code> or <code class="directive"><a href="./mod/mod_rewrite.html#rewriterule">RewriteRule</a></code> because they operate on different levels.
+ </p>
+
+
+<h3><a name="merge-examples" id="merge-examples">Some useful 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 &gt; B &gt; C &gt; D &gt;
+E.</p>
+
+<pre class="prettyprint lang-config">&lt;Location "/"&gt;
+ E
+&lt;/Location&gt;
+
+&lt;Files "f.html"&gt;
+ D
+&lt;/Files&gt;
+
+&lt;VirtualHost *&gt;
+ &lt;Directory "/a/b"&gt;
+ B
+ &lt;/Directory&gt;
+&lt;/VirtualHost&gt;
+
+&lt;DirectoryMatch "^.*b$"&gt;
+ C
+&lt;/DirectoryMatch&gt;
+
+&lt;Directory "/a/b"&gt;
+ A
+&lt;/Directory&gt;</pre>
+
+
+
+<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">&lt;Directory&gt;</a></code> sections, the <code class="directive"><a href="./mod/core.html#location">&lt;Location&gt;</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>
+
+<pre class="prettyprint lang-config">&lt;Location "/"&gt;
+ Require all granted
+&lt;/Location&gt;
+
+# Whoops! This &lt;Directory&gt; section will have no effect
+&lt;Directory "/"&gt;
+ &lt;RequireAll&gt;
+ Require all granted
+ Require not host badguy.example.com
+ &lt;/RequireAll&gt;
+&lt;/Directory&gt;</pre>
+
+
+
+
+</div></div>
+<div class="bottomlang">
+<p><span>Available Languages: </span><a href="./en/sections.html" title="English">&nbsp;en&nbsp;</a> |
+<a href="./fr/sections.html" hreflang="fr" rel="alternate" title="Français">&nbsp;fr&nbsp;</a> |
+<a href="./ja/sections.html" hreflang="ja" rel="alternate" title="Japanese">&nbsp;ja&nbsp;</a> |
+<a href="./ko/sections.html" hreflang="ko" rel="alternate" title="Korean">&nbsp;ko&nbsp;</a> |
+<a href="./tr/sections.html" hreflang="tr" rel="alternate" title="Türkçe">&nbsp;tr&nbsp;</a></p>
+</div><div class="top"><a href="#page-header"><img src="./images/up.gif" alt="top" /></a></div><div class="section"><h2><a id="comments_section" name="comments_section">Comments</a></h2><div class="warning"><strong>Notice:</strong><br />This is not a Q&amp;A section. Comments placed here should be pointed towards suggestions on improving the documentation or server, and may be removed by our moderators if they are either implemented or considered invalid/off-topic. Questions on how to manage the Apache HTTP Server should be directed at either our IRC channel, #httpd, on Libera.chat, or sent to our <a href="https://httpd.apache.org/lists.html">mailing lists</a>.</div>
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