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diff --git a/rubbos/app/httpd-2.0.64/docs/manual/mod/core.html.en b/rubbos/app/httpd-2.0.64/docs/manual/mod/core.html.en new file mode 100644 index 00000000..5b417797 --- /dev/null +++ b/rubbos/app/httpd-2.0.64/docs/manual/mod/core.html.en @@ -0,0 +1,3250 @@ +<?xml version="1.0" encoding="ISO-8859-1"?> +<!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><!-- + XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX + This file is generated from xml source: DO NOT EDIT + XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX + --> +<title>core - Apache HTTP Server</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 href="../images/favicon.ico" rel="shortcut icon" /></head> +<body> +<div id="page-header"> +<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 2.0</p> +<img alt="" src="../images/feather.gif" /></div> +<div class="up"><a href="./"><img title="<-" alt="<-" src="../images/left.gif" /></a></div> +<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 2.0</a> > <a href="./">Modules</a></div> +<div id="page-content"> +<div id="preamble"><h1>Apache Core Features</h1> +<div class="toplang"> +<p><span>Available Languages: </span><a href="../de/mod/core.html" hreflang="de" rel="alternate" title="Deutsch"> de </a> | +<a href="../en/mod/core.html" title="English"> en </a> | +<a href="../es/mod/core.html" hreflang="es" rel="alternate" title="Español"> es </a> | +<a href="../ja/mod/core.html" hreflang="ja" rel="alternate" title="Japanese"> ja </a> | +<a href="../tr/mod/core.html" hreflang="tr" rel="alternate" title="Türkçe"> tr </a></p> +</div> +<table class="module"><tr><th><a href="module-dict.html#Description">Description:</a></th><td>Core Apache HTTP Server features that are always +available</td></tr> +<tr><th><a href="module-dict.html#Status">Status:</a></th><td>Core</td></tr></table> +</div> +<div id="quickview"><h3 class="directives">Directives</h3> +<ul id="toc"> +<li><img alt="" src="../images/down.gif" /> <a href="#acceptpathinfo">AcceptPathInfo</a></li> +<li><img alt="" src="../images/down.gif" /> <a href="#accessfilename">AccessFileName</a></li> +<li><img alt="" src="../images/down.gif" /> <a href="#adddefaultcharset">AddDefaultCharset</a></li> +<li><img alt="" src="../images/down.gif" /> <a href="#addoutputfilterbytype">AddOutputFilterByType</a></li> +<li><img alt="" src="../images/down.gif" /> <a href="#allowencodedslashes">AllowEncodedSlashes</a></li> +<li><img alt="" src="../images/down.gif" /> <a href="#allowoverride">AllowOverride</a></li> +<li><img alt="" src="../images/down.gif" /> <a href="#authname">AuthName</a></li> +<li><img alt="" src="../images/down.gif" /> <a href="#authtype">AuthType</a></li> +<li><img alt="" src="../images/down.gif" /> <a href="#cgimapextension">CGIMapExtension</a></li> +<li><img alt="" src="../images/down.gif" /> <a href="#contentdigest">ContentDigest</a></li> +<li><img alt="" src="../images/down.gif" /> <a href="#defaulttype">DefaultType</a></li> +<li><img alt="" src="../images/down.gif" /> <a href="#directory"><Directory></a></li> +<li><img alt="" src="../images/down.gif" /> <a href="#directorymatch"><DirectoryMatch></a></li> +<li><img alt="" src="../images/down.gif" /> <a href="#documentroot">DocumentRoot</a></li> +<li><img alt="" src="../images/down.gif" /> <a href="#enablemmap">EnableMMAP</a></li> +<li><img alt="" src="../images/down.gif" /> <a href="#enablesendfile">EnableSendfile</a></li> +<li><img alt="" src="../images/down.gif" /> <a href="#errordocument">ErrorDocument</a></li> +<li><img alt="" src="../images/down.gif" /> <a href="#errorlog">ErrorLog</a></li> +<li><img alt="" src="../images/down.gif" /> <a href="#fileetag">FileETag</a></li> +<li><img alt="" src="../images/down.gif" /> <a href="#files"><Files></a></li> +<li><img alt="" src="../images/down.gif" /> <a href="#filesmatch"><FilesMatch></a></li> +<li><img alt="" src="../images/down.gif" /> <a href="#forcetype">ForceType</a></li> +<li><img alt="" src="../images/down.gif" /> <a href="#hostnamelookups">HostnameLookups</a></li> +<li><img alt="" src="../images/down.gif" /> <a href="#identitycheck">IdentityCheck</a></li> +<li><img alt="" src="../images/down.gif" /> <a href="#ifdefine"><IfDefine></a></li> +<li><img alt="" src="../images/down.gif" /> <a href="#ifmodule"><IfModule></a></li> +<li><img alt="" src="../images/down.gif" /> <a href="#include">Include</a></li> +<li><img alt="" src="../images/down.gif" /> <a href="#keepalive">KeepAlive</a></li> +<li><img alt="" src="../images/down.gif" /> <a href="#keepalivetimeout">KeepAliveTimeout</a></li> +<li><img alt="" src="../images/down.gif" /> <a href="#limit"><Limit></a></li> +<li><img alt="" src="../images/down.gif" /> <a href="#limitexcept"><LimitExcept></a></li> +<li><img alt="" src="../images/down.gif" /> <a href="#limitinternalrecursion">LimitInternalRecursion</a></li> +<li><img alt="" src="../images/down.gif" /> <a href="#limitrequestbody">LimitRequestBody</a></li> +<li><img alt="" src="../images/down.gif" /> <a href="#limitrequestfields">LimitRequestFields</a></li> +<li><img alt="" src="../images/down.gif" /> <a href="#limitrequestfieldsize">LimitRequestFieldSize</a></li> +<li><img alt="" src="../images/down.gif" /> <a href="#limitrequestline">LimitRequestLine</a></li> +<li><img alt="" src="../images/down.gif" /> <a href="#limitxmlrequestbody">LimitXMLRequestBody</a></li> +<li><img alt="" src="../images/down.gif" /> <a href="#location"><Location></a></li> +<li><img alt="" src="../images/down.gif" /> <a href="#locationmatch"><LocationMatch></a></li> +<li><img alt="" src="../images/down.gif" /> <a href="#loglevel">LogLevel</a></li> +<li><img alt="" src="../images/down.gif" /> <a href="#maxkeepaliverequests">MaxKeepAliveRequests</a></li> +<li><img alt="" src="../images/down.gif" /> <a href="#namevirtualhost">NameVirtualHost</a></li> +<li><img alt="" src="../images/down.gif" /> <a href="#options">Options</a></li> +<li><img alt="" src="../images/down.gif" /> <a href="#require">Require</a></li> +<li><img alt="" src="../images/down.gif" /> <a href="#rlimitcpu">RLimitCPU</a></li> +<li><img alt="" src="../images/down.gif" /> <a href="#rlimitmem">RLimitMEM</a></li> +<li><img alt="" src="../images/down.gif" /> <a href="#rlimitnproc">RLimitNPROC</a></li> +<li><img alt="" src="../images/down.gif" /> <a href="#satisfy">Satisfy</a></li> +<li><img alt="" src="../images/down.gif" /> <a href="#scriptinterpretersource">ScriptInterpreterSource</a></li> +<li><img alt="" src="../images/down.gif" /> <a href="#serveradmin">ServerAdmin</a></li> +<li><img alt="" src="../images/down.gif" /> <a href="#serveralias">ServerAlias</a></li> +<li><img alt="" src="../images/down.gif" /> <a href="#servername">ServerName</a></li> +<li><img alt="" src="../images/down.gif" /> <a href="#serverpath">ServerPath</a></li> +<li><img alt="" src="../images/down.gif" /> <a href="#serverroot">ServerRoot</a></li> +<li><img alt="" src="../images/down.gif" /> <a href="#serversignature">ServerSignature</a></li> +<li><img alt="" src="../images/down.gif" /> <a href="#servertokens">ServerTokens</a></li> +<li><img alt="" src="../images/down.gif" /> <a href="#sethandler">SetHandler</a></li> +<li><img alt="" src="../images/down.gif" /> <a href="#setinputfilter">SetInputFilter</a></li> +<li><img alt="" src="../images/down.gif" /> <a href="#setoutputfilter">SetOutputFilter</a></li> +<li><img alt="" src="../images/down.gif" /> <a href="#timeout">TimeOut</a></li> +<li><img alt="" src="../images/down.gif" /> <a href="#traceenable">TraceEnable</a></li> +<li><img alt="" src="../images/down.gif" /> <a href="#usecanonicalname">UseCanonicalName</a></li> +<li><img alt="" src="../images/down.gif" /> <a href="#virtualhost"><VirtualHost></a></li> +</ul> +</div> + +<div class="top"><a href="#page-header"><img alt="top" src="../images/up.gif" /></a></div> +<div class="directive-section"><h2><a name="AcceptPathInfo" id="AcceptPathInfo">AcceptPathInfo</a> <a name="acceptpathinfo" id="acceptpathinfo">Directive</a></h2> +<table class="directive"> +<tr><th><a href="directive-dict.html#Description">Description:</a></th><td>Resources accept trailing pathname information</td></tr> +<tr><th><a href="directive-dict.html#Syntax">Syntax:</a></th><td><code>AcceptPathInfo On|Off|Default</code></td></tr> +<tr><th><a href="directive-dict.html#Default">Default:</a></th><td><code>AcceptPathInfo Default</code></td></tr> +<tr><th><a href="directive-dict.html#Context">Context:</a></th><td>server config, virtual host, directory, .htaccess</td></tr> +<tr><th><a href="directive-dict.html#Override">Override:</a></th><td>FileInfo</td></tr> +<tr><th><a href="directive-dict.html#Status">Status:</a></th><td>Core</td></tr> +<tr><th><a href="directive-dict.html#Module">Module:</a></th><td>core</td></tr> +<tr><th><a href="directive-dict.html#Compatibility">Compatibility:</a></th><td>Available in Apache 2.0.30 and later</td></tr> +</table> + + <p>This directive controls whether requests that contain trailing + pathname information that follows an actual filename (or + non-existent file in an existing directory) will be accepted or + rejected. The trailing pathname information can be made + available to scripts in the <code>PATH_INFO</code> environment + variable.</p> + + <p>For example, assume the location <code>/test/</code> points to + a directory that contains only the single file + <code>here.html</code>. Then requests for + <code>/test/here.html/more</code> and + <code>/test/nothere.html/more</code> both collect + <code>/more</code> as <code>PATH_INFO</code>.</p> + + <p>The three possible arguments for the + <code class="directive">AcceptPathInfo</code> directive are:</p> + <dl> + <dt><code>Off</code></dt><dd>A request will only be accepted if it + maps to a literal path that exists. Therefore a request with + trailing pathname information after the true filename such as + <code>/test/here.html/more</code> in the above example will return + a 404 NOT FOUND error.</dd> + + <dt><code>On</code></dt><dd>A request will be accepted if a + leading path component maps to a file that exists. The above + example <code>/test/here.html/more</code> will be accepted if + <code>/test/here.html</code> maps to a valid file.</dd> + + <dt><code>Default</code></dt><dd>The treatment of requests with + trailing pathname information is determined by the <a href="../handler.html">handler</a> responsible for the request. + The core handler for normal files defaults to rejecting + <code>PATH_INFO</code> requests. Handlers that serve scripts, such as <a href="mod_cgi.html">cgi-script</a> and <a href="mod_isapi.html">isapi-handler</a>, generally accept + <code>PATH_INFO</code> by default.</dd> + </dl> + + <p>The primary purpose of the <code>AcceptPathInfo</code> + directive is to allow you to override the handler's choice of + accepting or rejecting <code>PATH_INFO</code>. This override is required, + for example, when you use a <a href="../filter.html">filter</a>, such + as <a href="mod_include.html">INCLUDES</a>, to generate content + based on <code>PATH_INFO</code>. The core handler would usually reject + the request, so you can use the following configuration to enable + such a script:</p> + + <div class="example"><p><code> + <Files "mypaths.shtml"><br /> + <span class="indent"> + Options +Includes<br /> + SetOutputFilter INCLUDES<br /> + AcceptPathInfo On<br /> + </span> + </Files> + </code></p></div> + + +</div> +<div class="top"><a href="#page-header"><img alt="top" src="../images/up.gif" /></a></div> +<div class="directive-section"><h2><a name="AccessFileName" id="AccessFileName">AccessFileName</a> <a name="accessfilename" id="accessfilename">Directive</a></h2> +<table class="directive"> +<tr><th><a href="directive-dict.html#Description">Description:</a></th><td>Name of the distributed configuration file</td></tr> +<tr><th><a href="directive-dict.html#Syntax">Syntax:</a></th><td><code>AccessFileName <var>filename</var> [<var>filename</var>] ...</code></td></tr> +<tr><th><a href="directive-dict.html#Default">Default:</a></th><td><code>AccessFileName .htaccess</code></td></tr> +<tr><th><a href="directive-dict.html#Context">Context:</a></th><td>server config, virtual host</td></tr> +<tr><th><a href="directive-dict.html#Status">Status:</a></th><td>Core</td></tr> +<tr><th><a href="directive-dict.html#Module">Module:</a></th><td>core</td></tr> +</table> + <p>While processing a request the server looks for + the first existing configuration file from this list of names in + every directory of the path to the document, if distributed + configuration files are <a href="#allowoverride">enabled for that + directory</a>. For example:</p> + + <div class="example"><p><code> + AccessFileName .acl + </code></p></div> + + <p>before returning the document + <code>/usr/local/web/index.html</code>, the server will read + <code>/.acl</code>, <code>/usr/.acl</code>, + <code>/usr/local/.acl</code> and <code>/usr/local/web/.acl</code> + for directives, unless they have been disabled with</p> + + <div class="example"><p><code> + <Directory /><br /> + <span class="indent"> + AllowOverride None<br /> + </span> + </Directory> + </code></p></div> + +<h3>See also</h3> +<ul> +<li><code class="directive"><a href="#allowoverride">AllowOverride</a></code></li> +<li><a href="../configuring.html">Configuration Files</a></li> +<li><a href="../howto/htaccess.html">.htaccess Files</a></li> +</ul> +</div> +<div class="top"><a href="#page-header"><img alt="top" src="../images/up.gif" /></a></div> +<div class="directive-section"><h2><a name="AddDefaultCharset" id="AddDefaultCharset">AddDefaultCharset</a> <a name="adddefaultcharset" id="adddefaultcharset">Directive</a></h2> +<table class="directive"> +<tr><th><a href="directive-dict.html#Description">Description:</a></th><td>Default charset parameter to be added when a response +content-type is <code>text/plain</code> or <code>text/html</code></td></tr> +<tr><th><a href="directive-dict.html#Syntax">Syntax:</a></th><td><code>AddDefaultCharset On|Off|<var>charset</var></code></td></tr> +<tr><th><a href="directive-dict.html#Default">Default:</a></th><td><code>AddDefaultCharset Off</code></td></tr> +<tr><th><a href="directive-dict.html#Context">Context:</a></th><td>server config, virtual host, directory, .htaccess</td></tr> +<tr><th><a href="directive-dict.html#Override">Override:</a></th><td>FileInfo</td></tr> +<tr><th><a href="directive-dict.html#Status">Status:</a></th><td>Core</td></tr> +<tr><th><a href="directive-dict.html#Module">Module:</a></th><td>core</td></tr> +</table> + <p>This directive specifies a default value for the media type + charset parameter (the name of a character encoding) to be added + to a response if and only if the response's content-type is either + <code>text/plain</code> or <code>text/html</code>. This should override + any charset specified in the body of the response via a <code>META</code> + element, though the exact behavior is often dependent on the user's client + configuration. A setting of <code>AddDefaultCharset Off</code> + disables this functionality. <code>AddDefaultCharset On</code> enables + a default charset of <code>iso-8859-1</code>. Any other value is assumed + to be the <var>charset</var> to be used, which should be one of the + <a href="http://www.iana.org/assignments/character-sets">IANA registered + charset values</a> for use in MIME media types. + For example:</p> + + <div class="example"><p><code> + AddDefaultCharset utf-8 + </code></p></div> + + <p><code class="directive">AddDefaultCharset</code> should only be used when all + of the text resources to which it applies are known to be in that + character encoding and it is too inconvenient to label their charset + individually. One such example is to add the charset parameter + to resources containing generated content, such as legacy CGI + scripts, that might be vulnerable to cross-site scripting attacks + due to user-provided data being included in the output. Note, however, + that a better solution is to just fix (or delete) those scripts, since + setting a default charset does not protect users that have enabled + the "auto-detect character encoding" feature on their browser.</p> + +<h3>See also</h3> +<ul> +<li><code class="directive"><a href="../mod/mod_mime.html#addcharset">AddCharset</a></code></li> +</ul> +</div> +<div class="top"><a href="#page-header"><img alt="top" src="../images/up.gif" /></a></div> +<div class="directive-section"><h2><a name="AddOutputFilterByType" id="AddOutputFilterByType">AddOutputFilterByType</a> <a name="addoutputfilterbytype" id="addoutputfilterbytype">Directive</a></h2> +<table class="directive"> +<tr><th><a href="directive-dict.html#Description">Description:</a></th><td>assigns an output filter to a particular MIME-type</td></tr> +<tr><th><a href="directive-dict.html#Syntax">Syntax:</a></th><td><code>AddOutputFilterByType <var>filter</var>[;<var>filter</var>...] +<var>MIME-type</var> [<var>MIME-type</var>] ...</code></td></tr> +<tr><th><a href="directive-dict.html#Context">Context:</a></th><td>server config, virtual host, directory, .htaccess</td></tr> +<tr><th><a href="directive-dict.html#Override">Override:</a></th><td>FileInfo</td></tr> +<tr><th><a href="directive-dict.html#Status">Status:</a></th><td>Core</td></tr> +<tr><th><a href="directive-dict.html#Module">Module:</a></th><td>core</td></tr> +<tr><th><a href="directive-dict.html#Compatibility">Compatibility:</a></th><td>Available in Apache 2.0.33 and later</td></tr> +</table> + <p>This directive activates a particular output <a href="../filter.html">filter</a> for a request depending on the + response MIME-type.</p> + + <p>The following example uses the <code>DEFLATE</code> filter, which + is provided by <code class="module"><a href="../mod/mod_deflate.html">mod_deflate</a></code>. It will compress all + output (either static or dynamic) which is labeled as + <code>text/html</code> or <code>text/plain</code> before it is sent + to the client.</p> + + <div class="example"><p><code> + AddOutputFilterByType DEFLATE text/html text/plain + </code></p></div> + + <p>If you want the content to be processed by more than one filter, their + names have to be separated by semicolons. It's also possible to use one + <code class="directive">AddOutputFilterByType</code> directive for each of + these filters.</p> + + <p>The configuration below causes all script output labeled as + <code>text/html</code> to be processed at first by the + <code>INCLUDES</code> filter and then by the <code>DEFLATE</code> + filter.</p> + + <div class="example"><p><code> + <Location /cgi-bin/><br /> + <span class="indent"> + Options Includes<br /> + AddOutputFilterByType INCLUDES;DEFLATE text/html<br /> + </span> + </Location> + </code></p></div> + + <div class="warning"><h3>Note</h3> + <p>Enabling filters with <code class="directive">AddOutputFilterByType</code> + may fail partially or completely in some cases. For example, no + filters are applied if the MIME-type could not be determined and falls + back to the <code class="directive"><a href="#defaulttype">DefaultType</a></code> setting, + even if the <code class="directive"><a href="#defaulttype">DefaultType</a></code> is the + same.</p> + + <p>However, if you want to make sure, that the filters will be + applied, assign the content type to a resource explicitly, for + example with <code class="directive"><a href="../mod/mod_mime.html#addtype">AddType</a></code> or + <code class="directive"><a href="#forcetype">ForceType</a></code>. Setting the + content type within a (non-nph) CGI script is also safe.</p> + + <p>The by-type output filters are never applied on proxy requests.</p> + </div> + +<h3>See also</h3> +<ul> +<li><code class="directive"><a href="../mod/mod_mime.html#addoutputfilter">AddOutputFilter</a></code></li> +<li><code class="directive"><a href="#setoutputfilter">SetOutputFilter</a></code></li> +<li><a href="../filter.html">filters</a></li> +</ul> +</div> +<div class="top"><a href="#page-header"><img alt="top" src="../images/up.gif" /></a></div> +<div class="directive-section"><h2><a name="AllowEncodedSlashes" id="AllowEncodedSlashes">AllowEncodedSlashes</a> <a name="allowencodedslashes" id="allowencodedslashes">Directive</a></h2> +<table class="directive"> +<tr><th><a href="directive-dict.html#Description">Description:</a></th><td>Determines whether encoded path separators in URLs are allowed to +be passed through</td></tr> +<tr><th><a href="directive-dict.html#Syntax">Syntax:</a></th><td><code>AllowEncodedSlashes On|Off</code></td></tr> +<tr><th><a href="directive-dict.html#Default">Default:</a></th><td><code>AllowEncodedSlashes Off</code></td></tr> +<tr><th><a href="directive-dict.html#Context">Context:</a></th><td>server config, virtual host</td></tr> +<tr><th><a href="directive-dict.html#Status">Status:</a></th><td>Core</td></tr> +<tr><th><a href="directive-dict.html#Module">Module:</a></th><td>core</td></tr> +<tr><th><a href="directive-dict.html#Compatibility">Compatibility:</a></th><td>Available in Apache 2.0.46 and later</td></tr> +</table> + <p>The <code class="directive">AllowEncodedSlashes</code> directive allows URLs + which contain encoded path separators (<code>%2F</code> for <code>/</code> + and additionally <code>%5C</code> for <code>\</code> on according systems) + to be used. Normally such URLs are refused with a 404 (Not found) error.</p> + + <p>Turning <code class="directive">AllowEncodedSlashes</code> <code>On</code> is + mostly useful when used in conjunction with <code>PATH_INFO</code>.</p> + + <div class="note"><h3>Note</h3> + <p>Allowing encoded slashes does <em>not</em> imply <em>decoding</em>. + Occurrences of <code>%2F</code> or <code>%5C</code> (<em>only</em> on + according systems) will be left as such in the otherwise decoded URL + string.</p> + </div> + +<h3>See also</h3> +<ul> +<li><code class="directive"><a href="#acceptpathinfo">AcceptPathInfo</a></code></li> +</ul> +</div> +<div class="top"><a href="#page-header"><img alt="top" src="../images/up.gif" /></a></div> +<div class="directive-section"><h2><a name="AllowOverride" id="AllowOverride">AllowOverride</a> <a name="allowoverride" id="allowoverride">Directive</a></h2> +<table class="directive"> +<tr><th><a href="directive-dict.html#Description">Description:</a></th><td>Types of directives that are allowed in +<code>.htaccess</code> files</td></tr> +<tr><th><a href="directive-dict.html#Syntax">Syntax:</a></th><td><code>AllowOverride All|None|<var>directive-type</var> +[<var>directive-type</var>] ...</code></td></tr> +<tr><th><a href="directive-dict.html#Default">Default:</a></th><td><code>AllowOverride All</code></td></tr> +<tr><th><a href="directive-dict.html#Context">Context:</a></th><td>directory</td></tr> +<tr><th><a href="directive-dict.html#Status">Status:</a></th><td>Core</td></tr> +<tr><th><a href="directive-dict.html#Module">Module:</a></th><td>core</td></tr> +</table> + <p>When the server finds an <code>.htaccess</code> file (as + specified by <code class="directive"><a href="#accessfilename">AccessFileName</a></code>) + it needs to know which directives declared in that file can override + earlier configuration directives.</p> + + <div class="note"><h3>Only available in <Directory> sections</h3> + <code class="directive">AllowOverride</code> is valid only in + <code class="directive"><a href="#directory"><Directory></a></code> + sections specified without regular expressions, not in <code class="directive"><a href="#location"><Location></a></code>, <code class="directive"><a href="#directorymatch"><DirectoryMatch></a></code> or + <code class="directive"><a href="#files"><Files></a></code> sections. + </div> + + <p>When this directive is set to <code>None</code>, then + <a href="#accessfilename">.htaccess</a> files are completely ignored. + In this case, the server will not even attempt to read + <code>.htaccess</code> files in the filesystem.</p> + + <p>When this directive is set to <code>All</code>, then any + directive which has the .htaccess <a href="directive-dict.html#Context">Context</a> is allowed in + <code>.htaccess</code> files.</p> + + <p>The <var>directive-type</var> can be one of the following + groupings of directives.</p> + + <dl> + <dt>AuthConfig</dt> + + <dd> + + Allow use of the authorization directives (<code class="directive"><a href="../mod/mod_auth_dbm.html#authdbmgroupfile">AuthDBMGroupFile</a></code>, + <code class="directive"><a href="../mod/mod_auth_dbm.html#authdbmuserfile">AuthDBMUserFile</a></code>, + <code class="directive"><a href="../mod/mod_auth.html#authgroupfile">AuthGroupFile</a></code>, + <code class="directive"><a href="#authname">AuthName</a></code>, + <code class="directive"><a href="#authtype">AuthType</a></code>, <code class="directive"><a href="../mod/mod_auth.html#authuserfile">AuthUserFile</a></code>, <code class="directive"><a href="#require">Require</a></code>, <em>etc.</em>).</dd> + + <dt>FileInfo</dt> + + <dd> + Allow use of the directives controlling document types (<code class="directive"><a href="#defaulttype">DefaultType</a></code>, <code class="directive"><a href="#errordocument">ErrorDocument</a></code>, <code class="directive"><a href="#forcetype">ForceType</a></code>, <code class="directive"><a href="../mod/mod_negotiation.html#languagepriority">LanguagePriority</a></code>, + <code class="directive"><a href="#sethandler">SetHandler</a></code>, <code class="directive"><a href="#setinputfilter">SetInputFilter</a></code>, <code class="directive"><a href="#setoutputfilter">SetOutputFilter</a></code>, and + <code class="module"><a href="../mod/mod_mime.html">mod_mime</a></code> Add* and Remove* + directives, <em>etc.</em>).</dd> + + <dt>Indexes</dt> + + <dd> + Allow use of the directives controlling directory indexing + (<code class="directive"><a href="../mod/mod_autoindex.html#adddescription">AddDescription</a></code>, + <code class="directive"><a href="../mod/mod_autoindex.html#addicon">AddIcon</a></code>, <code class="directive"><a href="../mod/mod_autoindex.html#addiconbyencoding">AddIconByEncoding</a></code>, + <code class="directive"><a href="../mod/mod_autoindex.html#addiconbytype">AddIconByType</a></code>, + <code class="directive"><a href="../mod/mod_autoindex.html#defaulticon">DefaultIcon</a></code>, <code class="directive"><a href="../mod/mod_dir.html#directoryindex">DirectoryIndex</a></code>, <code class="directive"><a href="../mod/mod_autoindex.html#fancyindexing">FancyIndexing</a></code>, <code class="directive"><a href="../mod/mod_autoindex.html#headername">HeaderName</a></code>, <code class="directive"><a href="../mod/mod_autoindex.html#indexignore">IndexIgnore</a></code>, <code class="directive"><a href="../mod/mod_autoindex.html#indexoptions">IndexOptions</a></code>, <code class="directive"><a href="../mod/mod_autoindex.html#readmename">ReadmeName</a></code>, + <em>etc.</em>).</dd> + + <dt>Limit</dt> + + <dd> + Allow use of the directives controlling host access (<code class="directive"><a href="../mod/mod_access.html#allow">Allow</a></code>, <code class="directive"><a href="../mod/mod_access.html#deny">Deny</a></code> and <code class="directive"><a href="../mod/mod_access.html#order">Order</a></code>).</dd> + + <dt>Options</dt> + + <dd> + Allow use of the directives controlling specific directory + features (<code class="directive"><a href="#options">Options</a></code> and + <code class="directive"><a href="../mod/mod_include.html#xbithack">XBitHack</a></code>).</dd> + </dl> + + <p>Example:</p> + + <div class="example"><p><code> + AllowOverride AuthConfig Indexes + </code></p></div> + + <p>In the example above all directives that are neither in the group + <code>AuthConfig</code> nor <code>Indexes</code> cause an internal + server error.</p> + +<h3>See also</h3> +<ul> +<li><code class="directive"><a href="#accessfilename">AccessFileName</a></code></li> +<li><a href="../configuring.html">Configuration Files</a></li> +<li><a href="../howto/htaccess.html">.htaccess Files</a></li> +</ul> +</div> +<div class="top"><a href="#page-header"><img alt="top" src="../images/up.gif" /></a></div> +<div class="directive-section"><h2><a name="AuthName" id="AuthName">AuthName</a> <a name="authname" id="authname">Directive</a></h2> +<table class="directive"> +<tr><th><a href="directive-dict.html#Description">Description:</a></th><td>Authorization realm for use in HTTP +authentication</td></tr> +<tr><th><a href="directive-dict.html#Syntax">Syntax:</a></th><td><code>AuthName <var>auth-domain</var></code></td></tr> +<tr><th><a href="directive-dict.html#Context">Context:</a></th><td>directory, .htaccess</td></tr> +<tr><th><a href="directive-dict.html#Override">Override:</a></th><td>AuthConfig</td></tr> +<tr><th><a href="directive-dict.html#Status">Status:</a></th><td>Core</td></tr> +<tr><th><a href="directive-dict.html#Module">Module:</a></th><td>core</td></tr> +</table> + <p>This directive sets the name of the authorization realm for a + directory. This realm is given to the client so that the user + knows which username and password to send. + <code class="directive">AuthName</code> takes a single argument; if the + realm name contains spaces, it must be enclosed in quotation + marks. It must be accompanied by <code class="directive"><a href="#authtype">AuthType</a></code> and <code class="directive"><a href="#require">Require</a></code> directives, and directives such + as <code class="directive"><a href="../mod/mod_auth.html#authuserfile">AuthUserFile</a></code> and + <code class="directive"><a href="../mod/mod_auth.html#authgroupfile">AuthGroupFile</a></code> to + work.</p> + + <p>For example:</p> + + <div class="example"><p><code> + AuthName "Top Secret" + </code></p></div> + + <p>The string provided for the <code>AuthName</code> is what will + appear in the password dialog provided by most browsers.</p> + +<h3>See also</h3> +<ul> +<li><a href="../howto/auth.html">Authentication, Authorization, and + Access Control</a></li> +</ul> +</div> +<div class="top"><a href="#page-header"><img alt="top" src="../images/up.gif" /></a></div> +<div class="directive-section"><h2><a name="AuthType" id="AuthType">AuthType</a> <a name="authtype" id="authtype">Directive</a></h2> +<table class="directive"> +<tr><th><a href="directive-dict.html#Description">Description:</a></th><td>Type of user authentication</td></tr> +<tr><th><a href="directive-dict.html#Syntax">Syntax:</a></th><td><code>AuthType Basic|Digest</code></td></tr> +<tr><th><a href="directive-dict.html#Context">Context:</a></th><td>directory, .htaccess</td></tr> +<tr><th><a href="directive-dict.html#Override">Override:</a></th><td>AuthConfig</td></tr> +<tr><th><a href="directive-dict.html#Status">Status:</a></th><td>Core</td></tr> +<tr><th><a href="directive-dict.html#Module">Module:</a></th><td>core</td></tr> +</table> + <p>This directive selects the type of user authentication for a + directory. Only <code>Basic</code> and <code>Digest</code> are + currently implemented. + + It must be accompanied by <code class="directive"><a href="#authname">AuthName</a></code> and <code class="directive"><a href="#require">Require</a></code> directives, and directives such + as <code class="directive"><a href="../mod/mod_auth.html#authuserfile">AuthUserFile</a></code> and + <code class="directive"><a href="../mod/mod_auth.html#authgroupfile">AuthGroupFile</a></code> to + work.</p> + +<h3>See also</h3> +<ul> +<li><a href="../howto/auth.html">Authentication, Authorization, +and Access Control</a></li> +</ul> +</div> +<div class="top"><a href="#page-header"><img alt="top" src="../images/up.gif" /></a></div> +<div class="directive-section"><h2><a name="CGIMapExtension" id="CGIMapExtension">CGIMapExtension</a> <a name="cgimapextension" id="cgimapextension">Directive</a></h2> +<table class="directive"> +<tr><th><a href="directive-dict.html#Description">Description:</a></th><td>Technique for locating the interpreter for CGI +scripts</td></tr> +<tr><th><a href="directive-dict.html#Syntax">Syntax:</a></th><td><code>CGIMapExtension <var>cgi-path</var> <var>.extension</var></code></td></tr> +<tr><th><a href="directive-dict.html#Context">Context:</a></th><td>directory, .htaccess</td></tr> +<tr><th><a href="directive-dict.html#Override">Override:</a></th><td>FileInfo</td></tr> +<tr><th><a href="directive-dict.html#Status">Status:</a></th><td>Core</td></tr> +<tr><th><a href="directive-dict.html#Module">Module:</a></th><td>core</td></tr> +<tr><th><a href="directive-dict.html#Compatibility">Compatibility:</a></th><td>NetWare only</td></tr> +</table> + <p>This directive is used to control how Apache finds the + interpreter used to run CGI scripts. For example, setting + <code>CGIMapExtension sys:\foo.nlm .foo</code> will + cause all CGI script files with a <code>.foo</code> extension to + be passed to the FOO interpreter.</p> + +</div> +<div class="top"><a href="#page-header"><img alt="top" src="../images/up.gif" /></a></div> +<div class="directive-section"><h2><a name="ContentDigest" id="ContentDigest">ContentDigest</a> <a name="contentdigest" id="contentdigest">Directive</a></h2> +<table class="directive"> +<tr><th><a href="directive-dict.html#Description">Description:</a></th><td>Enables the generation of <code>Content-MD5</code> HTTP Response +headers</td></tr> +<tr><th><a href="directive-dict.html#Syntax">Syntax:</a></th><td><code>ContentDigest On|Off</code></td></tr> +<tr><th><a href="directive-dict.html#Default">Default:</a></th><td><code>ContentDigest Off</code></td></tr> +<tr><th><a href="directive-dict.html#Context">Context:</a></th><td>server config, virtual host, directory, .htaccess</td></tr> +<tr><th><a href="directive-dict.html#Override">Override:</a></th><td>Options</td></tr> +<tr><th><a href="directive-dict.html#Status">Status:</a></th><td>Core</td></tr> +<tr><th><a href="directive-dict.html#Module">Module:</a></th><td>core</td></tr> +</table> + <p>This directive enables the generation of + <code>Content-MD5</code> headers as defined in RFC1864 + respectively RFC2068.</p> + + <p>MD5 is an algorithm for computing a "message digest" + (sometimes called "fingerprint") of arbitrary-length data, with + a high degree of confidence that any alterations in the data + will be reflected in alterations in the message digest.</p> + + <p>The <code>Content-MD5</code> header provides an end-to-end + message integrity check (MIC) of the entity-body. A proxy or + client may check this header for detecting accidental + modification of the entity-body in transit. Example header:</p> + + <div class="example"><p><code> + Content-MD5: AuLb7Dp1rqtRtxz2m9kRpA== + </code></p></div> + + <p>Note that this can cause performance problems on your server + since the message digest is computed on every request (the + values are not cached).</p> + + <p><code>Content-MD5</code> is only sent for documents served + by the <code class="module"><a href="../mod/core.html">core</a></code>, and not by any module. For example, + SSI documents, output from CGI scripts, and byte range responses + do not have this header.</p> + +</div> +<div class="top"><a href="#page-header"><img alt="top" src="../images/up.gif" /></a></div> +<div class="directive-section"><h2><a name="DefaultType" id="DefaultType">DefaultType</a> <a name="defaulttype" id="defaulttype">Directive</a></h2> +<table class="directive"> +<tr><th><a href="directive-dict.html#Description">Description:</a></th><td>MIME content-type that will be sent if the +server cannot determine a type in any other way</td></tr> +<tr><th><a href="directive-dict.html#Syntax">Syntax:</a></th><td><code>DefaultType <var>MIME-type</var></code></td></tr> +<tr><th><a href="directive-dict.html#Default">Default:</a></th><td><code>DefaultType text/plain</code></td></tr> +<tr><th><a href="directive-dict.html#Context">Context:</a></th><td>server config, virtual host, directory, .htaccess</td></tr> +<tr><th><a href="directive-dict.html#Override">Override:</a></th><td>FileInfo</td></tr> +<tr><th><a href="directive-dict.html#Status">Status:</a></th><td>Core</td></tr> +<tr><th><a href="directive-dict.html#Module">Module:</a></th><td>core</td></tr> +</table> + <p>There will be times when the server is asked to provide a + document whose type cannot be determined by its MIME types + mappings.</p> + + <p>The server must inform the client of the content-type of the + document, so in the event of an unknown type it uses the + <code>DefaultType</code>. For example:</p> + + <div class="example"><p><code> + DefaultType image/gif + </code></p></div> + + <p>would be appropriate for a directory which contained many GIF + images with filenames missing the <code>.gif</code> extension.</p> + + <p>Note that unlike <code class="directive"><a href="#forcetype">ForceType</a></code>, this directive only + provides the default mime-type. All other mime-type definitions, + including filename extensions, that might identify the media type + will override this default.</p> + +</div> +<div class="top"><a href="#page-header"><img alt="top" src="../images/up.gif" /></a></div> +<div class="directive-section"><h2><a name="Directory" id="Directory"><Directory></a> <a name="directory" id="directory">Directive</a></h2> +<table class="directive"> +<tr><th><a href="directive-dict.html#Description">Description:</a></th><td>Enclose a group of directives that apply only to the +named file-system directory and sub-directories</td></tr> +<tr><th><a href="directive-dict.html#Syntax">Syntax:</a></th><td><code><Directory <var>directory-path</var>> +... </Directory></code></td></tr> +<tr><th><a href="directive-dict.html#Context">Context:</a></th><td>server config, virtual host</td></tr> +<tr><th><a href="directive-dict.html#Status">Status:</a></th><td>Core</td></tr> +<tr><th><a href="directive-dict.html#Module">Module:</a></th><td>core</td></tr> +</table> + <p><code class="directive"><Directory></code> and + <code></Directory></code> are used to enclose a group of + directives that will apply only to the named directory and + sub-directories of that directory. Any directive that is allowed + in a directory context may be used. <var>Directory-path</var> is + either the full path to a directory, or a wild-card string using + Unix shell-style matching. In a wild-card string, <code>?</code> matches + any single character, and <code>*</code> matches any sequences of + characters. You may also use <code>[]</code> character ranges. None + of the wildcards match a `/' character, so <code><Directory + /*/public_html></code> will not match + <code>/home/user/public_html</code>, but <code><Directory + /home/*/public_html></code> will match. Example:</p> + + <div class="example"><p><code> + <Directory /usr/local/httpd/htdocs><br /> + <span class="indent"> + Options Indexes FollowSymLinks<br /> + </span> + </Directory> + </code></p></div> + + <div class="note"> + <p>Be careful with the <var>directory-path</var> arguments: + They have to literally match the filesystem path which Apache uses + to access the files. Directives applied to a particular + <code><Directory></code> will not apply to files accessed from + that same directory via a different path, such as via different symbolic + links.</p> + </div> + + <p>Extended regular + expressions can also be used, with the addition of the + <code>~</code> character. For example:</p> + + <div class="example"><p><code> + <Directory ~ "^/www/.*/[0-9]{3}"> + </code></p></div> + + <p>would match directories in <code>/www/</code> that consisted of + three numbers.</p> + + <p>If multiple (non-regular expression) <code class="directive"><Directory></code> sections + match the directory (or one of its parents) containing a document, + then the directives are applied in the order of shortest match + first, interspersed with the directives from the <a href="#accessfilename">.htaccess</a> files. For example, + with</p> + + <div class="example"><p><code> + <Directory /><br /> + <span class="indent"> + AllowOverride None<br /> + </span> + </Directory><br /> + <br /> + <Directory /home/><br /> + <span class="indent"> + AllowOverride FileInfo<br /> + </span> + </Directory> + </code></p></div> + + <p>for access to the document <code>/home/web/dir/doc.html</code> + the steps are:</p> + + <ul> + <li>Apply directive <code>AllowOverride None</code> + (disabling <code>.htaccess</code> files).</li> + + <li>Apply directive <code>AllowOverride FileInfo</code> (for + directory <code>/home</code>).</li> + + <li>Apply any <code>FileInfo</code> directives in + <code>/home/.htaccess</code>, <code>/home/web/.htaccess</code> and + <code>/home/web/dir/.htaccess</code> in that order.</li> + </ul> + + <p>Regular expressions are not considered until after all of the + normal sections have been applied. Then all of the regular + expressions are tested in the order they appeared in the + configuration file. For example, with</p> + + <div class="example"><p><code> + <Directory ~ abc$><br /> + <span class="indent"> + # ... directives here ...<br /> + </span> + </Directory> + </code></p></div> + + <p>the regular expression section won't be considered until after + all normal <code class="directive"><Directory></code>s and + <code>.htaccess</code> files have been applied. Then the regular + expression will match on <code>/home/abc/public_html/abc</code> and + the corresponding <code class="directive"><Directory></code> will + be applied.</p> + + <p><strong>Note that the default Apache access for + <code><Directory /></code> is <code>Allow from All</code>. + This means that Apache will serve any file mapped from an URL. It is + recommended that you change this with a block such + as</strong></p> + + <div class="example"><p><code> + <Directory /><br /> + <span class="indent"> + Order Deny,Allow<br /> + Deny from All<br /> + </span> + </Directory> + </code></p></div> + + <p><strong>and then override this for directories you + <em>want</em> accessible. See the <a href="../misc/security_tips.html">Security Tips</a> page for more + details.</strong></p> + + <p>The directory sections occur in the <code>httpd.conf</code> file. + <code class="directive"><Directory></code> directives + cannot nest, and cannot appear in a <code class="directive"><a href="#limit"><Limit></a></code> or <code class="directive"><a href="#limitexcept"><LimitExcept></a></code> section.</p> + +<h3>See also</h3> +<ul> +<li><a href="../sections.html">How <Directory>, + <Location> and <Files> sections work</a> for an + explanation of how these different sections are combined when a + request is received</li> +</ul> +</div> +<div class="top"><a href="#page-header"><img alt="top" src="../images/up.gif" /></a></div> +<div class="directive-section"><h2><a name="DirectoryMatch" id="DirectoryMatch"><DirectoryMatch></a> <a name="directorymatch" id="directorymatch">Directive</a></h2> +<table class="directive"> +<tr><th><a href="directive-dict.html#Description">Description:</a></th><td>Enclose directives that apply to +file-system directories matching a regular expression and their +subdirectories</td></tr> +<tr><th><a href="directive-dict.html#Syntax">Syntax:</a></th><td><code><DirectoryMatch <var>regex</var>> +... </DirectoryMatch></code></td></tr> +<tr><th><a href="directive-dict.html#Context">Context:</a></th><td>server config, virtual host</td></tr> +<tr><th><a href="directive-dict.html#Status">Status:</a></th><td>Core</td></tr> +<tr><th><a href="directive-dict.html#Module">Module:</a></th><td>core</td></tr> +</table> + <p><code class="directive"><DirectoryMatch></code> and + <code></DirectoryMatch></code> are used to enclose a group + of directives which will apply only to the named directory and + sub-directories of that directory, the same as <code class="directive"><a href="#directory"><Directory></a></code>. However, it + takes as an argument a regular expression. For example:</p> + + <div class="example"><p><code> + <DirectoryMatch "^/www/(.+/)?[0-9]{3}"> + </code></p></div> + + <p>would match directories in <code>/www/</code> that consisted of three + numbers.</p> + +<h3>See also</h3> +<ul> +<li><code class="directive"><a href="#directory"><Directory></a></code> for +a description of how regular expressions are mixed in with normal +<code class="directive"><Directory></code>s</li> +<li><a href="../sections.html">How <Directory>, <Location> and +<Files> sections work</a> for an explanation of how these different +sections are combined when a request is received</li> +</ul> +</div> +<div class="top"><a href="#page-header"><img alt="top" src="../images/up.gif" /></a></div> +<div class="directive-section"><h2><a name="DocumentRoot" id="DocumentRoot">DocumentRoot</a> <a name="documentroot" id="documentroot">Directive</a></h2> +<table class="directive"> +<tr><th><a href="directive-dict.html#Description">Description:</a></th><td>Directory that forms the main document tree visible +from the web</td></tr> +<tr><th><a href="directive-dict.html#Syntax">Syntax:</a></th><td><code>DocumentRoot <var>directory-path</var></code></td></tr> +<tr><th><a href="directive-dict.html#Default">Default:</a></th><td><code>DocumentRoot /usr/local/apache/htdocs</code></td></tr> +<tr><th><a href="directive-dict.html#Context">Context:</a></th><td>server config, virtual host</td></tr> +<tr><th><a href="directive-dict.html#Status">Status:</a></th><td>Core</td></tr> +<tr><th><a href="directive-dict.html#Module">Module:</a></th><td>core</td></tr> +</table> + <p>This directive sets the directory from which <code class="program"><a href="../programs/httpd.html">httpd</a></code> + will serve files. Unless matched by a directive like <code class="directive"><a href="../mod/mod_alias.html#alias">Alias</a></code>, the server appends the + path from the requested URL to the document root to make the + path to the document. Example:</p> + + <div class="example"><p><code> + DocumentRoot /usr/web + </code></p></div> + + <p>then an access to + <code>http://www.my.host.com/index.html</code> refers to + <code>/usr/web/index.html</code>.</p> + + <p>The <code class="directive">DocumentRoot</code> should be specified without + a trailing slash.</p> + +<h3>See also</h3> +<ul> +<li><a href="../urlmapping.html">Mapping URLs to Filesystem +Location</a></li> +</ul> +</div> +<div class="top"><a href="#page-header"><img alt="top" src="../images/up.gif" /></a></div> +<div class="directive-section"><h2><a name="EnableMMAP" id="EnableMMAP">EnableMMAP</a> <a name="enablemmap" id="enablemmap">Directive</a></h2> +<table class="directive"> +<tr><th><a href="directive-dict.html#Description">Description:</a></th><td>Use memory-mapping to read files during delivery</td></tr> +<tr><th><a href="directive-dict.html#Syntax">Syntax:</a></th><td><code>EnableMMAP On|Off</code></td></tr> +<tr><th><a href="directive-dict.html#Default">Default:</a></th><td><code>EnableMMAP On</code></td></tr> +<tr><th><a href="directive-dict.html#Context">Context:</a></th><td>server config, virtual host, directory, .htaccess</td></tr> +<tr><th><a href="directive-dict.html#Override">Override:</a></th><td>FileInfo</td></tr> +<tr><th><a href="directive-dict.html#Status">Status:</a></th><td>Core</td></tr> +<tr><th><a href="directive-dict.html#Module">Module:</a></th><td>core</td></tr> +</table> + <p>This directive controls whether the <code class="program"><a href="../programs/httpd.html">httpd</a></code> may use + memory-mapping if it needs to read the contents of a file during + delivery. By default, when the handling of a request requires + access to the data within a file -- for example, when delivering a + server-parsed file using <code class="module"><a href="../mod/mod_include.html">mod_include</a></code> -- Apache + memory-maps the file if the OS supports it.</p> + + <p>This memory-mapping sometimes yields a performance improvement. + But in some environments, it is better to disable the memory-mapping + to prevent operational problems:</p> + + <ul> + <li>On some multiprocessor systems, memory-mapping can reduce the + performance of the <code class="program"><a href="../programs/httpd.html">httpd</a></code>.</li> + <li>With an NFS-mounted <code class="directive"><a href="#documentroot">DocumentRoot</a></code>, + the <code class="program"><a href="../programs/httpd.html">httpd</a></code> may crash due to a segmentation fault if a file + is deleted or truncated while the <code class="program"><a href="../programs/httpd.html">httpd</a></code> has it + memory-mapped.</li> + </ul> + + <p>For server configurations that are vulnerable to these problems, + you should disable memory-mapping of delivered files by specifying:</p> + + <div class="example"><p><code> + EnableMMAP Off + </code></p></div> + + <p>For NFS mounted files, this feature may be disabled explicitly for + the offending files by specifying:</p> + + <div class="example"><p><code> + <Directory "/path-to-nfs-files"> + <span class="indent"> + EnableMMAP Off + </span> + </Directory> + </code></p></div> + +</div> +<div class="top"><a href="#page-header"><img alt="top" src="../images/up.gif" /></a></div> +<div class="directive-section"><h2><a name="EnableSendfile" id="EnableSendfile">EnableSendfile</a> <a name="enablesendfile" id="enablesendfile">Directive</a></h2> +<table class="directive"> +<tr><th><a href="directive-dict.html#Description">Description:</a></th><td>Use the kernel sendfile support to deliver files to the client</td></tr> +<tr><th><a href="directive-dict.html#Syntax">Syntax:</a></th><td><code>EnableSendfile On|Off</code></td></tr> +<tr><th><a href="directive-dict.html#Default">Default:</a></th><td><code>EnableSendfile On</code></td></tr> +<tr><th><a href="directive-dict.html#Context">Context:</a></th><td>server config, virtual host, directory, .htaccess</td></tr> +<tr><th><a href="directive-dict.html#Override">Override:</a></th><td>FileInfo</td></tr> +<tr><th><a href="directive-dict.html#Status">Status:</a></th><td>Core</td></tr> +<tr><th><a href="directive-dict.html#Module">Module:</a></th><td>core</td></tr> +<tr><th><a href="directive-dict.html#Compatibility">Compatibility:</a></th><td>Available in version 2.0.44 and later</td></tr> +</table> + <p>This directive controls whether <code class="program"><a href="../programs/httpd.html">httpd</a></code> may use the + sendfile support from the kernel to transmit file contents to the client. + By default, when the handling of a request requires no access + to the data within a file -- for example, when delivering a + static file -- Apache uses sendfile to deliver the file contents + without ever reading the file if the OS supports it.</p> + + <p>This sendfile mechanism avoids separate read and send operations, + and buffer allocations. But on some platforms or within some + filesystems, it is better to disable this feature to avoid + operational problems:</p> + + <ul> + <li>Some platforms may have broken sendfile support that the build + system did not detect, especially if the binaries were built on + another box and moved to such a machine with broken sendfile + support.</li> + <li>On Linux the use of sendfile triggers TCP-checksum + offloading bugs on certain networking cards when using IPv6.</li> + <li>With a network-mounted <code class="directive"><a href="#documentroot">DocumentRoot</a></code> (e.g., NFS or SMB), + the kernel may be unable to serve the network file through + its own cache.</li> + </ul> + + <p>For server configurations that are vulnerable to these problems, + you should disable this feature by specifying:</p> + + <div class="example"><p><code> + EnableSendfile Off + </code></p></div> + + <p>For NFS or SMB mounted files, this feature may be disabled explicitly + for the offending files by specifying:</p> + + <div class="example"><p><code> + <Directory "/path-to-nfs-files"> + <span class="indent"> + EnableSendfile Off + </span> + </Directory> + </code></p></div> + +</div> +<div class="top"><a href="#page-header"><img alt="top" src="../images/up.gif" /></a></div> +<div class="directive-section"><h2><a name="ErrorDocument" id="ErrorDocument">ErrorDocument</a> <a name="errordocument" id="errordocument">Directive</a></h2> +<table class="directive"> +<tr><th><a href="directive-dict.html#Description">Description:</a></th><td>What the server will return to the client +in case of an error</td></tr> +<tr><th><a href="directive-dict.html#Syntax">Syntax:</a></th><td><code>ErrorDocument <var>error-code</var> <var>document</var></code></td></tr> +<tr><th><a href="directive-dict.html#Context">Context:</a></th><td>server config, virtual host, directory, .htaccess</td></tr> +<tr><th><a href="directive-dict.html#Override">Override:</a></th><td>FileInfo</td></tr> +<tr><th><a href="directive-dict.html#Status">Status:</a></th><td>Core</td></tr> +<tr><th><a href="directive-dict.html#Module">Module:</a></th><td>core</td></tr> +<tr><th><a href="directive-dict.html#Compatibility">Compatibility:</a></th><td>Quoting syntax for text messages is different in Apache +2.0</td></tr> +</table> + <p>In the event of a problem or error, Apache can be configured + to do one of four things,</p> + + <ol> + <li>output a simple hardcoded error message</li> + + <li>output a customized message</li> + + <li>redirect to a local <var>URL-path</var> to handle the + problem/error</li> + + <li>redirect to an external <var>URL</var> to handle the + problem/error</li> + </ol> + + <p>The first option is the default, while options 2-4 are + configured using the <code class="directive">ErrorDocument</code> + directive, which is followed by the HTTP response code and a URL + or a message. Apache will sometimes offer additional information + regarding the problem/error.</p> + + <p>URLs can begin with a slash (/) for local web-paths (relative + to the <code class="directive"><a href="#documentroot">DocumentRoot</a></code>), or be a + full URL which the client can resolve. Alternatively, a message + can be provided to be displayed by the browser. Examples:</p> + + <div class="example"><p><code> + ErrorDocument 500 http://foo.example.com/cgi-bin/tester<br /> + ErrorDocument 404 /cgi-bin/bad_urls.pl<br /> + ErrorDocument 401 /subscription_info.html<br /> + ErrorDocument 403 "Sorry can't allow you access today" + </code></p></div> + + <p>Additionally, the special value <code>default</code> can be used + to specify Apache's simple hardcoded message. While not required + under normal circumstances, <code>default</code> will restore + Apache's simple hardcoded message for configurations that would + otherwise inherit an existing <code class="directive">ErrorDocument</code>.</p> + + <div class="example"><p><code> + ErrorDocument 404 /cgi-bin/bad_urls.pl<br /><br /> + <Directory /web/docs><br /> + <span class="indent"> + ErrorDocument 404 default<br /> + </span> + </Directory> + </code></p></div> + + <p>Note that when you specify an <code class="directive">ErrorDocument</code> + that points to a remote URL (ie. anything with a method such as + <code>http</code> in front of it), Apache will send a redirect to the + client to tell it where to find the document, even if the + document ends up being on the same server. This has several + implications, the most important being that the client will not + receive the original error status code, but instead will + receive a redirect status code. This in turn can confuse web + robots and other clients which try to determine if a URL is + valid using the status code. In addition, if you use a remote + URL in an <code>ErrorDocument 401</code>, the client will not + know to prompt the user for a password since it will not + receive the 401 status code. Therefore, <strong>if you use an + <code>ErrorDocument 401</code> directive then it must refer to a local + document.</strong></p> + + <p>Microsoft Internet Explorer (MSIE) will by default ignore + server-generated error messages when they are "too small" and substitute + its own "friendly" error messages. The size threshold varies depending on + the type of error, but in general, if you make your error document + greater than 512 bytes, then MSIE will show the server-generated + error rather than masking it. More information is available in + Microsoft Knowledge Base article <a href="http://support.microsoft.com/default.aspx?scid=kb;en-us;Q294807">Q294807</a>.</p> + + <p>Although most error messages can be overriden, there are certain + circumstances where the internal messages are used regardless of the + setting of <code class="directive"><a href="#errordocument">ErrorDocument</a></code>. In + particular, if a malformed request is detected, normal request processing + will be immediately halted and the internal error message returned. + This is necessary to guard against security problems caused by + bad requests.</p> + + <p>If you are using mod_proxy, you may wish to enable + <code class="directive"><a href="../mod/mod_proxy.html#proxyerroroverride">ProxyErrorOverride</a></code> so that you can provide + custom error messages on behalf of your Origin servers. If you don't enable ProxyErrorOverride, + Apache will not generate custom error documents for proxied content.</p> + + <p>Prior to version 2.0, messages were indicated by prefixing + them with a single unmatched double quote character.</p> + +<h3>See also</h3> +<ul> +<li><a href="../custom-error.html">documentation of + customizable responses</a></li> +</ul> +</div> +<div class="top"><a href="#page-header"><img alt="top" src="../images/up.gif" /></a></div> +<div class="directive-section"><h2><a name="ErrorLog" id="ErrorLog">ErrorLog</a> <a name="errorlog" id="errorlog">Directive</a></h2> +<table class="directive"> +<tr><th><a href="directive-dict.html#Description">Description:</a></th><td>Location where the server will log errors</td></tr> +<tr><th><a href="directive-dict.html#Syntax">Syntax:</a></th><td><code> ErrorLog <var>file-path</var>|syslog[:<var>facility</var>]</code></td></tr> +<tr><th><a href="directive-dict.html#Default">Default:</a></th><td><code>ErrorLog logs/error_log (Unix) ErrorLog logs/error.log (Windows and OS/2)</code></td></tr> +<tr><th><a href="directive-dict.html#Context">Context:</a></th><td>server config, virtual host</td></tr> +<tr><th><a href="directive-dict.html#Status">Status:</a></th><td>Core</td></tr> +<tr><th><a href="directive-dict.html#Module">Module:</a></th><td>core</td></tr> +</table> + <p>The <code class="directive">ErrorLog</code> directive sets the name of + the file to which the server will log any errors it encounters. If + the <var>file-path</var> is not absolute then it is assumed to be + relative to the <code class="directive"><a href="#serverroot">ServerRoot</a></code>.</p> + + <div class="example"><h3>Example</h3><p><code> + ErrorLog /var/log/httpd/error_log + </code></p></div> + + <p>If the <var>file-path</var> + begins with a pipe (|) then it is assumed to be a command to spawn + to handle the error log.</p> + + <div class="example"><h3>Example</h3><p><code> + ErrorLog "|/usr/local/bin/httpd_errors" + </code></p></div> + + <p>Using <code>syslog</code> instead of a filename enables logging + via syslogd(8) if the system supports it. The default is to use + syslog facility <code>local7</code>, but you can override this by + using the <code>syslog:<var>facility</var></code> syntax where + <var>facility</var> can be one of the names usually documented in + syslog(1).</p> + + <div class="example"><h3>Example</h3><p><code> + ErrorLog syslog:user + </code></p></div> + + <p>SECURITY: See the <a href="../misc/security_tips.html#serverroot">security tips</a> + document for details on why your security could be compromised + if the directory where log files are stored is writable by + anyone other than the user that starts the server.</p> + <div class="warning"><h3>Note</h3> + <p>When entering a file path on non-Unix platforms, care should be taken + to make sure that only forward slashed are used even though the platform + may allow the use of back slashes. In general it is a good idea to always + use forward slashes throughout the configuration files.</p> + </div> + +<h3>See also</h3> +<ul> +<li><code class="directive"><a href="#loglevel">LogLevel</a></code></li> +<li><a href="../logs.html">Apache Log Files</a></li> +</ul> +</div> +<div class="top"><a href="#page-header"><img alt="top" src="../images/up.gif" /></a></div> +<div class="directive-section"><h2><a name="FileETag" id="FileETag">FileETag</a> <a name="fileetag" id="fileetag">Directive</a></h2> +<table class="directive"> +<tr><th><a href="directive-dict.html#Description">Description:</a></th><td>File attributes used to create the ETag +HTTP response header</td></tr> +<tr><th><a href="directive-dict.html#Syntax">Syntax:</a></th><td><code>FileETag <var>component</var> ...</code></td></tr> +<tr><th><a href="directive-dict.html#Default">Default:</a></th><td><code>FileETag INode MTime Size</code></td></tr> +<tr><th><a href="directive-dict.html#Context">Context:</a></th><td>server config, virtual host, directory, .htaccess</td></tr> +<tr><th><a href="directive-dict.html#Override">Override:</a></th><td>FileInfo</td></tr> +<tr><th><a href="directive-dict.html#Status">Status:</a></th><td>Core</td></tr> +<tr><th><a href="directive-dict.html#Module">Module:</a></th><td>core</td></tr> +</table> + <p> + The <code class="directive">FileETag</code> directive configures the file + attributes that are used to create the <code>ETag</code> (entity + tag) response header field when the document is based on a file. + (The <code>ETag</code> value is used in cache management to save + network bandwidth.) In Apache 1.3.22 and earlier, the + <code>ETag</code> value was <em>always</em> formed + from the file's inode, size, and last-modified time (mtime). The + <code class="directive">FileETag</code> directive allows you to choose + which of these -- if any -- should be used. The recognized keywords are: + </p> + + <dl> + <dt><strong>INode</strong></dt> + <dd>The file's i-node number will be included in the calculation</dd> + <dt><strong>MTime</strong></dt> + <dd>The date and time the file was last modified will be included</dd> + <dt><strong>Size</strong></dt> + <dd>The number of bytes in the file will be included</dd> + <dt><strong>All</strong></dt> + <dd>All available fields will be used. This is equivalent to: + <div class="example"><p><code>FileETag INode MTime Size</code></p></div></dd> + <dt><strong>None</strong></dt> + <dd>If a document is file-based, no <code>ETag</code> field will be + included in the response</dd> + </dl> + + <p>The <code>INode</code>, <code>MTime</code>, and <code>Size</code> + keywords may be prefixed with either <code>+</code> or <code>-</code>, + which allow changes to be made to the default setting inherited + from a broader scope. Any keyword appearing without such a prefix + immediately and completely cancels the inherited setting.</p> + + <p>If a directory's configuration includes + <code>FileETag INode MTime Size</code>, and a + subdirectory's includes <code>FileETag -INode</code>, + the setting for that subdirectory (which will be inherited by + any sub-subdirectories that don't override it) will be equivalent to + <code>FileETag MTime Size</code>.</p> + +</div> +<div class="top"><a href="#page-header"><img alt="top" src="../images/up.gif" /></a></div> +<div class="directive-section"><h2><a name="Files" id="Files"><Files></a> <a name="files" id="files">Directive</a></h2> +<table class="directive"> +<tr><th><a href="directive-dict.html#Description">Description:</a></th><td>Contains directives that apply to matched +filenames</td></tr> +<tr><th><a href="directive-dict.html#Syntax">Syntax:</a></th><td><code><Files <var>filename</var>> ... </Files></code></td></tr> +<tr><th><a href="directive-dict.html#Context">Context:</a></th><td>server config, virtual host, directory, .htaccess</td></tr> +<tr><th><a href="directive-dict.html#Override">Override:</a></th><td>All</td></tr> +<tr><th><a href="directive-dict.html#Status">Status:</a></th><td>Core</td></tr> +<tr><th><a href="directive-dict.html#Module">Module:</a></th><td>core</td></tr> +</table> + <p>The <code class="directive"><Files></code> directive + limits the scope of the enclosed directives by filename. It is comparable + to the <code class="directive"><a href="#directory"><Directory></a></code> + and <code class="directive"><a href="#location"><Location></a></code> + directives. It should be matched with a <code></Files></code> + directive. The directives given within this section will be applied to + any object with a basename (last component of filename) matching the + specified filename. <code class="directive"><Files></code> + sections are processed in the order they appear in the + configuration file, after the <code class="directive"><a href="#directory"><Directory></a></code> sections and + <code>.htaccess</code> files are read, but before <code class="directive"><a href="#location"><Location></a></code> sections. Note + that <code class="directive"><Files></code> can be nested + inside <code class="directive"><a href="#directory"><Directory></a></code> sections to restrict the + portion of the filesystem they apply to.</p> + + <p>The <var>filename</var> argument should include a filename, or + a wild-card string, where <code>?</code> matches any single character, + and <code>*</code> matches any sequences of characters. Extended regular + expressions can also be used, with the addition of the + <code>~</code> character. For example:</p> + + <div class="example"><p><code> + <Files ~ "\.(gif|jpe?g|png)$"> + </code></p></div> + + <p>would match most common Internet graphics formats. <code class="directive"><a href="#filesmatch"><FilesMatch></a></code> is preferred, + however.</p> + + <p>Note that unlike <code class="directive"><a href="#directory"><Directory></a></code> and <code class="directive"><a href="#location"><Location></a></code> sections, <code class="directive"><Files></code> sections can be used inside + <code>.htaccess</code> files. This allows users to control access to + their own files, at a file-by-file level.</p> + + +<h3>See also</h3> +<ul> +<li><a href="../sections.html">How <Directory>, <Location> + and <Files> sections work</a> for an explanation of how these + different sections are combined when a request is received</li> +</ul> +</div> +<div class="top"><a href="#page-header"><img alt="top" src="../images/up.gif" /></a></div> +<div class="directive-section"><h2><a name="FilesMatch" id="FilesMatch"><FilesMatch></a> <a name="filesmatch" id="filesmatch">Directive</a></h2> +<table class="directive"> +<tr><th><a href="directive-dict.html#Description">Description:</a></th><td>Contains directives that apply to regular-expression matched +filenames</td></tr> +<tr><th><a href="directive-dict.html#Syntax">Syntax:</a></th><td><code><FilesMatch <var>regex</var>> ... </FilesMatch></code></td></tr> +<tr><th><a href="directive-dict.html#Context">Context:</a></th><td>server config, virtual host, directory, .htaccess</td></tr> +<tr><th><a href="directive-dict.html#Override">Override:</a></th><td>All</td></tr> +<tr><th><a href="directive-dict.html#Status">Status:</a></th><td>Core</td></tr> +<tr><th><a href="directive-dict.html#Module">Module:</a></th><td>core</td></tr> +</table> + <p>The <code class="directive"><FilesMatch></code> directive + limits the scope of the enclosed directives by filename, just as the + <code class="directive"><a href="#files"><Files></a></code> directive + does. However, it accepts a regular expression. For example:</p> + + <div class="example"><p><code> + <FilesMatch "\.(gif|jpe?g|png)$"> + </code></p></div> + + <p>would match most common Internet graphics formats.</p> + +<h3>See also</h3> +<ul> +<li><a href="../sections.html">How <Directory>, <Location> + and <Files> sections work</a> for an explanation of how these + different sections are combined when a request is received</li> +</ul> +</div> +<div class="top"><a href="#page-header"><img alt="top" src="../images/up.gif" /></a></div> +<div class="directive-section"><h2><a name="ForceType" id="ForceType">ForceType</a> <a name="forcetype" id="forcetype">Directive</a></h2> +<table class="directive"> +<tr><th><a href="directive-dict.html#Description">Description:</a></th><td>Forces all matching files to be served with the specified +MIME content-type</td></tr> +<tr><th><a href="directive-dict.html#Syntax">Syntax:</a></th><td><code>ForceType <var>MIME-type</var>|None</code></td></tr> +<tr><th><a href="directive-dict.html#Context">Context:</a></th><td>directory, .htaccess</td></tr> +<tr><th><a href="directive-dict.html#Override">Override:</a></th><td>FileInfo</td></tr> +<tr><th><a href="directive-dict.html#Status">Status:</a></th><td>Core</td></tr> +<tr><th><a href="directive-dict.html#Module">Module:</a></th><td>core</td></tr> +<tr><th><a href="directive-dict.html#Compatibility">Compatibility:</a></th><td>Moved to the core in Apache 2.0</td></tr> +</table> + <p>When placed into an <code>.htaccess</code> file or a + <code class="directive"><a href="#directory"><Directory></a></code>, or + <code class="directive"><a href="#location"><Location></a></code> or + <code class="directive"><a href="#files"><Files></a></code> + section, this directive forces all matching files to be served + with the content type identification given by + <var>MIME-type</var>. For example, if you had a directory full of + GIF files, but did not want to label them all with <code>.gif</code>, + you might want to use:</p> + + <div class="example"><p><code> + ForceType image/gif + </code></p></div> + + <p>Note that unlike <code class="directive"><a href="#defaulttype">DefaultType</a></code>, + this directive overrides all mime-type associations, including + filename extensions, that might identify the media type.</p> + + <p>You can override any <code class="directive">ForceType</code> setting + by using the value of <code>None</code>:</p> + + <div class="example"><p><code> + # force all files to be image/gif:<br /> + <Location /images><br /> + <span class="indent"> + ForceType image/gif<br /> + </span> + </Location><br /> + <br /> + # but normal mime-type associations here:<br /> + <Location /images/mixed><br /> + <span class="indent"> + ForceType None<br /> + </span> + </Location> + </code></p></div> + +</div> +<div class="top"><a href="#page-header"><img alt="top" src="../images/up.gif" /></a></div> +<div class="directive-section"><h2><a name="HostnameLookups" id="HostnameLookups">HostnameLookups</a> <a name="hostnamelookups" id="hostnamelookups">Directive</a></h2> +<table class="directive"> +<tr><th><a href="directive-dict.html#Description">Description:</a></th><td>Enables DNS lookups on client IP addresses</td></tr> +<tr><th><a href="directive-dict.html#Syntax">Syntax:</a></th><td><code>HostnameLookups On|Off|Double</code></td></tr> +<tr><th><a href="directive-dict.html#Default">Default:</a></th><td><code>HostnameLookups Off</code></td></tr> +<tr><th><a href="directive-dict.html#Context">Context:</a></th><td>server config, virtual host, directory</td></tr> +<tr><th><a href="directive-dict.html#Status">Status:</a></th><td>Core</td></tr> +<tr><th><a href="directive-dict.html#Module">Module:</a></th><td>core</td></tr> +</table> + <p>This directive enables DNS lookups so that host names can be + logged (and passed to CGIs/SSIs in <code>REMOTE_HOST</code>). + The value <code>Double</code> refers to doing double-reverse + DNS lookup. That is, after a reverse lookup is performed, a forward + lookup is then performed on that result. At least one of the IP + addresses in the forward lookup must match the original + address. (In "tcpwrappers" terminology this is called + <code>PARANOID</code>.)</p> + + <p>Regardless of the setting, when <code class="module"><a href="../mod/mod_access.html">mod_access</a></code> is + used for controlling access by hostname, a double reverse lookup + will be performed. This is necessary for security. Note that the + result of this double-reverse isn't generally available unless you + set <code>HostnameLookups Double</code>. For example, if only + <code>HostnameLookups On</code> and a request is made to an object + that is protected by hostname restrictions, regardless of whether + the double-reverse fails or not, CGIs will still be passed the + single-reverse result in <code>REMOTE_HOST</code>.</p> + + <p>The default is <code>Off</code> in order to save the network + traffic for those sites that don't truly need the reverse + lookups done. It is also better for the end users because they + don't have to suffer the extra latency that a lookup entails. + Heavily loaded sites should leave this directive + <code>Off</code>, since DNS lookups can take considerable + amounts of time. The utility <code class="program"><a href="../programs/logresolve.html">logresolve</a></code>, compiled by + default to the <code>bin</code> subdirectory of your installation + directory, can be used to look up host names from logged IP addresses + offline.</p> + +</div> +<div class="top"><a href="#page-header"><img alt="top" src="../images/up.gif" /></a></div> +<div class="directive-section"><h2><a name="IdentityCheck" id="IdentityCheck">IdentityCheck</a> <a name="identitycheck" id="identitycheck">Directive</a></h2> +<table class="directive"> +<tr><th><a href="directive-dict.html#Description">Description:</a></th><td>Enables logging of the RFC1413 identity of the remote +user</td></tr> +<tr><th><a href="directive-dict.html#Syntax">Syntax:</a></th><td><code>IdentityCheck On|Off</code></td></tr> +<tr><th><a href="directive-dict.html#Default">Default:</a></th><td><code>IdentityCheck Off</code></td></tr> +<tr><th><a href="directive-dict.html#Context">Context:</a></th><td>server config, virtual host, directory</td></tr> +<tr><th><a href="directive-dict.html#Status">Status:</a></th><td>Core</td></tr> +<tr><th><a href="directive-dict.html#Module">Module:</a></th><td>core</td></tr> +</table> + <p>This directive enables RFC1413-compliant logging of the + remote user name for each connection, where the client machine + runs identd or something similar. This information is logged in + the access log.</p> + + <p>The information should not be trusted in any way except for + rudimentary usage tracking.</p> + + <p>Note that this can cause serious latency problems accessing + your server since every request requires one of these lookups + to be performed. When firewalls are involved each lookup might + possibly fail and add 30 seconds of latency to each hit. So in + general this is not very useful on public servers accessible + from the Internet.</p> + +</div> +<div class="top"><a href="#page-header"><img alt="top" src="../images/up.gif" /></a></div> +<div class="directive-section"><h2><a name="IfDefine" id="IfDefine"><IfDefine></a> <a name="ifdefine" id="ifdefine">Directive</a></h2> +<table class="directive"> +<tr><th><a href="directive-dict.html#Description">Description:</a></th><td>Encloses directives that will be processed only +if a test is true at startup</td></tr> +<tr><th><a href="directive-dict.html#Syntax">Syntax:</a></th><td><code><IfDefine [!]<var>parameter-name</var>> ... + </IfDefine></code></td></tr> +<tr><th><a href="directive-dict.html#Context">Context:</a></th><td>server config, virtual host, directory, .htaccess</td></tr> +<tr><th><a href="directive-dict.html#Override">Override:</a></th><td>All</td></tr> +<tr><th><a href="directive-dict.html#Status">Status:</a></th><td>Core</td></tr> +<tr><th><a href="directive-dict.html#Module">Module:</a></th><td>core</td></tr> +</table> + <p>The <code><IfDefine <var>test</var>>...</IfDefine> + </code> section is used to mark directives that are conditional. The + directives within an <code class="directive"><IfDefine></code> + section are only processed if the <var>test</var> is true. If <var> + test</var> is false, everything between the start and end markers is + ignored.</p> + + <p>The <var>test</var> in the <code class="directive"><IfDefine></code> section directive can be one of two forms:</p> + + <ul> + <li><var>parameter-name</var></li> + + <li><code>!</code><var>parameter-name</var></li> + </ul> + + <p>In the former case, the directives between the start and end + markers are only processed if the parameter named + <var>parameter-name</var> is defined. The second format reverses + the test, and only processes the directives if + <var>parameter-name</var> is <strong>not</strong> defined.</p> + + <p>The <var>parameter-name</var> argument is a define as given on + the <code class="program"><a href="../programs/httpd.html">httpd</a></code> command line via <code>-D<var>parameter-</var> + </code>, at the time the server was started.</p> + + <p><code class="directive"><IfDefine></code> sections are + nest-able, which can be used to implement simple + multiple-parameter tests. Example:</p> + + <div class="example"><p><code> + httpd -DReverseProxy ...<br /> + <br /> + # httpd.conf<br /> + <IfDefine ReverseProxy><br /> + <span class="indent"> + LoadModule rewrite_module modules/mod_rewrite.so<br /> + LoadModule proxy_module modules/libproxy.so<br /> + </span> + </IfDefine> + </code></p></div> + +</div> +<div class="top"><a href="#page-header"><img alt="top" src="../images/up.gif" /></a></div> +<div class="directive-section"><h2><a name="IfModule" id="IfModule"><IfModule></a> <a name="ifmodule" id="ifmodule">Directive</a></h2> +<table class="directive"> +<tr><th><a href="directive-dict.html#Description">Description:</a></th><td>Encloses directives that are processed conditional on the +presence or absence of a specific module</td></tr> +<tr><th><a href="directive-dict.html#Syntax">Syntax:</a></th><td><code><IfModule [!]<var>module-name</var>> ... + </IfModule></code></td></tr> +<tr><th><a href="directive-dict.html#Context">Context:</a></th><td>server config, virtual host, directory, .htaccess</td></tr> +<tr><th><a href="directive-dict.html#Override">Override:</a></th><td>All</td></tr> +<tr><th><a href="directive-dict.html#Status">Status:</a></th><td>Core</td></tr> +<tr><th><a href="directive-dict.html#Module">Module:</a></th><td>core</td></tr> +</table> + <p>The <code><IfModule <var>test</var>>...</IfModule></code> + section is used to mark directives that are conditional on the presence of + a specific module. The directives within an <code class="directive"><IfModule></code> section are only processed if the <var>test</var> + is true. If <var>test</var> is false, everything between the start and + end markers is ignored.</p> + + <p>The <var>test</var> in the <code class="directive"><IfModule></code> section directive can be one of two forms:</p> + + <ul> + <li><var>module name</var></li> + + <li>!<var>module name</var></li> + </ul> + + <p>In the former case, the directives between the start and end + markers are only processed if the module named <var>module + name</var> is included in Apache -- either compiled in or + dynamically loaded using <code class="directive"><a href="../mod/mod_so.html#loadmodule">LoadModule</a></code>. The second format reverses the test, + and only processes the directives if <var>module name</var> is + <strong>not</strong> included.</p> + + <p>The <var>module name</var> argument is the file name of the + module, at the time it was compiled. For example, + <code>mod_rewrite.c</code>. If a module consists of several + source files, use the name of the file containing the string + <code>STANDARD20_MODULE_STUFF</code>.</p> + + <p><code class="directive"><IfModule></code> sections are + nest-able, which can be used to implement simple multiple-module + tests.</p> + + <div class="note">This section should only be used if you need to have one + configuration file that works whether or not a specific module + is available. In normal operation, directives need not be + placed in <code class="directive"><IfModule></code> + sections.</div> + +</div> +<div class="top"><a href="#page-header"><img alt="top" src="../images/up.gif" /></a></div> +<div class="directive-section"><h2><a name="Include" id="Include">Include</a> <a name="include" id="include">Directive</a></h2> +<table class="directive"> +<tr><th><a href="directive-dict.html#Description">Description:</a></th><td>Includes other configuration files from within +the server configuration files</td></tr> +<tr><th><a href="directive-dict.html#Syntax">Syntax:</a></th><td><code>Include <var>file-path</var>|<var>directory-path</var></code></td></tr> +<tr><th><a href="directive-dict.html#Context">Context:</a></th><td>server config, virtual host, directory</td></tr> +<tr><th><a href="directive-dict.html#Status">Status:</a></th><td>Core</td></tr> +<tr><th><a href="directive-dict.html#Module">Module:</a></th><td>core</td></tr> +<tr><th><a href="directive-dict.html#Compatibility">Compatibility:</a></th><td>Wildcard matching available in 2.0.41 and later</td></tr> +</table> + <p>This directive allows inclusion of other configuration files + from within the server configuration files.</p> + + <p>Shell-style (<code>fnmatch()</code>) wildcard characters can be used to + include several files at once, in alphabetical order. In + addition, if <code class="directive">Include</code> points to a directory, + rather than a file, Apache will read all files in that directory + and any subdirectory. But including entire directories is not + recommended, because it is easy to accidentally leave temporary + files in a directory that can cause <code class="program"><a href="../programs/httpd.html">httpd</a></code> to + fail.</p> + + <p>The file path specified may be an absolute path, or may be relative + to the <code class="directive"><a href="#serverroot">ServerRoot</a></code> directory.</p> + + <p>Examples:</p> + + <div class="example"><p><code> + Include /usr/local/apache2/conf/ssl.conf<br /> + Include /usr/local/apache2/conf/vhosts/*.conf + </code></p></div> + + <p>Or, providing paths relative to your <code class="directive"><a href="#serverroot">ServerRoot</a></code> directory:</p> + + <div class="example"><p><code> + Include conf/ssl.conf<br /> + Include conf/vhosts/*.conf + </code></p></div> + +<h3>See also</h3> +<ul> +<li><code class="program"><a href="../programs/apachectl.html">apachectl</a></code></li> +</ul> +</div> +<div class="top"><a href="#page-header"><img alt="top" src="../images/up.gif" /></a></div> +<div class="directive-section"><h2><a name="KeepAlive" id="KeepAlive">KeepAlive</a> <a name="keepalive" id="keepalive">Directive</a></h2> +<table class="directive"> +<tr><th><a href="directive-dict.html#Description">Description:</a></th><td>Enables HTTP persistent connections</td></tr> +<tr><th><a href="directive-dict.html#Syntax">Syntax:</a></th><td><code>KeepAlive On|Off</code></td></tr> +<tr><th><a href="directive-dict.html#Default">Default:</a></th><td><code>KeepAlive On</code></td></tr> +<tr><th><a href="directive-dict.html#Context">Context:</a></th><td>server config, virtual host</td></tr> +<tr><th><a href="directive-dict.html#Status">Status:</a></th><td>Core</td></tr> +<tr><th><a href="directive-dict.html#Module">Module:</a></th><td>core</td></tr> +</table> + <p>The Keep-Alive extension to HTTP/1.0 and the persistent + connection feature of HTTP/1.1 provide long-lived HTTP sessions + which allow multiple requests to be sent over the same TCP + connection. In some cases this has been shown to result in an + almost 50% speedup in latency times for HTML documents with + many images. To enable Keep-Alive connections, set + <code>KeepAlive On</code>.</p> + + <p>For HTTP/1.0 clients, Keep-Alive connections will only be + used if they are specifically requested by a client. In + addition, a Keep-Alive connection with an HTTP/1.0 client can + only be used when the length of the content is known in + advance. This implies that dynamic content such as CGI output, + SSI pages, and server-generated directory listings will + generally not use Keep-Alive connections to HTTP/1.0 clients. + For HTTP/1.1 clients, persistent connections are the default + unless otherwise specified. If the client requests it, chunked + encoding will be used in order to send content of unknown + length over persistent connections.</p> + +<h3>See also</h3> +<ul> +<li><code class="directive"><a href="#maxkeepaliverequests">MaxKeepAliveRequests</a></code></li> +</ul> +</div> +<div class="top"><a href="#page-header"><img alt="top" src="../images/up.gif" /></a></div> +<div class="directive-section"><h2><a name="KeepAliveTimeout" id="KeepAliveTimeout">KeepAliveTimeout</a> <a name="keepalivetimeout" id="keepalivetimeout">Directive</a></h2> +<table class="directive"> +<tr><th><a href="directive-dict.html#Description">Description:</a></th><td>Amount of time the server will wait for subsequent +requests on a persistent connection</td></tr> +<tr><th><a href="directive-dict.html#Syntax">Syntax:</a></th><td><code>KeepAliveTimeout <var>seconds</var></code></td></tr> +<tr><th><a href="directive-dict.html#Default">Default:</a></th><td><code>KeepAliveTimeout 15</code></td></tr> +<tr><th><a href="directive-dict.html#Context">Context:</a></th><td>server config, virtual host</td></tr> +<tr><th><a href="directive-dict.html#Status">Status:</a></th><td>Core</td></tr> +<tr><th><a href="directive-dict.html#Module">Module:</a></th><td>core</td></tr> +</table> + <p>The number of seconds Apache will wait for a subsequent + request before closing the connection. Once a request has been + received, the timeout value specified by the + <code class="directive"><a href="#timeout">Timeout</a></code> directive applies.</p> + + <p>Setting <code class="directive">KeepAliveTimeout</code> to a high value + may cause performance problems in heavily loaded servers. The + higher the timeout, the more server processes will be kept + occupied waiting on connections with idle clients.</p> + + <p>In a name-based virtual host context, the value of the first + defined virtual host (the default host) in a set of <code class="directive"><a href="#namevirtualhost">NameVirtualHost</a></code> will be used. + The other values will be ignored.</p> + +</div> +<div class="top"><a href="#page-header"><img alt="top" src="../images/up.gif" /></a></div> +<div class="directive-section"><h2><a name="Limit" id="Limit"><Limit></a> <a name="limit" id="limit">Directive</a></h2> +<table class="directive"> +<tr><th><a href="directive-dict.html#Description">Description:</a></th><td>Restrict enclosed access controls to only certain HTTP +methods</td></tr> +<tr><th><a href="directive-dict.html#Syntax">Syntax:</a></th><td><code><Limit <var>method</var> [<var>method</var>] ... > ... + </Limit></code></td></tr> +<tr><th><a href="directive-dict.html#Context">Context:</a></th><td>server config, virtual host, directory, .htaccess</td></tr> +<tr><th><a href="directive-dict.html#Override">Override:</a></th><td>All</td></tr> +<tr><th><a href="directive-dict.html#Status">Status:</a></th><td>Core</td></tr> +<tr><th><a href="directive-dict.html#Module">Module:</a></th><td>core</td></tr> +</table> + <p>Access controls are normally effective for + <strong>all</strong> access methods, and this is the usual + desired behavior. <strong>In the general case, access control + directives should not be placed within a + <code class="directive"><Limit></code> section.</strong></p> + + <p>The purpose of the <code class="directive"><Limit></code> + directive is to restrict the effect of the access controls to the + nominated HTTP methods. For all other methods, the access + restrictions that are enclosed in the <code class="directive"><Limit></code> bracket <strong>will have no + effect</strong>. The following example applies the access control + only to the methods <code>POST</code>, <code>PUT</code>, and + <code>DELETE</code>, leaving all other methods unprotected:</p> + + <div class="example"><p><code> + <Limit POST PUT DELETE><br /> + <span class="indent"> + Require valid-user<br /> + </span> + </Limit> + </code></p></div> + + <p>The method names listed can be one or more of: <code>GET</code>, + <code>POST</code>, <code>PUT</code>, <code>DELETE</code>, + <code>CONNECT</code>, <code>OPTIONS</code>, + <code>PATCH</code>, <code>PROPFIND</code>, <code>PROPPATCH</code>, + <code>MKCOL</code>, <code>COPY</code>, <code>MOVE</code>, + <code>LOCK</code>, and <code>UNLOCK</code>. <strong>The method name is + case-sensitive.</strong> If <code>GET</code> is used it will also + restrict <code>HEAD</code> requests. The <code>TRACE</code> method + cannot be limited.</p> + + <div class="warning">A <code class="directive"><a href="#limitexcept"><LimitExcept></a></code> section should always be + used in preference to a <code class="directive"><a href="#limit"><Limit></a></code> section when restricting access, + since a <code class="directive"><a href="#limitexcept"><LimitExcept></a></code> section provides protection + against arbitrary methods.</div> + + +</div> +<div class="top"><a href="#page-header"><img alt="top" src="../images/up.gif" /></a></div> +<div class="directive-section"><h2><a name="LimitExcept" id="LimitExcept"><LimitExcept></a> <a name="limitexcept" id="limitexcept">Directive</a></h2> +<table class="directive"> +<tr><th><a href="directive-dict.html#Description">Description:</a></th><td>Restrict access controls to all HTTP methods +except the named ones</td></tr> +<tr><th><a href="directive-dict.html#Syntax">Syntax:</a></th><td><code><LimitExcept <var>method</var> [<var>method</var>] ... > ... + </LimitExcept></code></td></tr> +<tr><th><a href="directive-dict.html#Context">Context:</a></th><td>server config, virtual host, directory, .htaccess</td></tr> +<tr><th><a href="directive-dict.html#Override">Override:</a></th><td>All</td></tr> +<tr><th><a href="directive-dict.html#Status">Status:</a></th><td>Core</td></tr> +<tr><th><a href="directive-dict.html#Module">Module:</a></th><td>core</td></tr> +</table> + <p><code class="directive"><LimitExcept></code> and + <code></LimitExcept></code> are used to enclose + a group of access control directives which will then apply to any + HTTP access method <strong>not</strong> listed in the arguments; + i.e., it is the opposite of a <code class="directive"><a href="#limit"><Limit></a></code> section and can be used to control + both standard and nonstandard/unrecognized methods. See the + documentation for <code class="directive"><a href="#limit"><Limit></a></code> for more details.</p> + + <p>For example:</p> + + <div class="example"><p><code> + <LimitExcept POST GET><br /> + <span class="indent"> + Require valid-user<br /> + </span> + </LimitExcept> + </code></p></div> + + +</div> +<div class="top"><a href="#page-header"><img alt="top" src="../images/up.gif" /></a></div> +<div class="directive-section"><h2><a name="LimitInternalRecursion" id="LimitInternalRecursion">LimitInternalRecursion</a> <a name="limitinternalrecursion" id="limitinternalrecursion">Directive</a></h2> +<table class="directive"> +<tr><th><a href="directive-dict.html#Description">Description:</a></th><td>Determine maximum number of internal redirects and nested +subrequests</td></tr> +<tr><th><a href="directive-dict.html#Syntax">Syntax:</a></th><td><code>LimitInternalRecursion <var>number</var> [<var>number</var>]</code></td></tr> +<tr><th><a href="directive-dict.html#Default">Default:</a></th><td><code>LimitInternalRecursion 10</code></td></tr> +<tr><th><a href="directive-dict.html#Context">Context:</a></th><td>server config, virtual host</td></tr> +<tr><th><a href="directive-dict.html#Status">Status:</a></th><td>Core</td></tr> +<tr><th><a href="directive-dict.html#Module">Module:</a></th><td>core</td></tr> +<tr><th><a href="directive-dict.html#Compatibility">Compatibility:</a></th><td>Available in Apache 2.0.47 and later</td></tr> +</table> + <p>An internal redirect happens, for example, when using the <code class="directive"><a href="../mod/mod_actions.html#action">Action</a></code> directive, which internally + redirects the original request to a CGI script. A subrequest is Apache's + mechanism to find out what would happen for some URI if it were requested. + For example, <code class="module"><a href="../mod/mod_dir.html">mod_dir</a></code> uses subrequests to look for the + files listed in the <code class="directive"><a href="../mod/mod_dir.html#directoryindex">DirectoryIndex</a></code> + directive.</p> + + <p><code class="directive">LimitInternalRecursion</code> prevents the server + from crashing when entering an infinite loop of internal redirects or + subrequests. Such loops are usually caused by misconfigurations.</p> + + <p>The directive stores two different limits, which are evaluated on + per-request basis. The first <var>number</var> is the maximum number of + internal redirects, that may follow each other. The second <var>number</var> + determines, how deep subrequests may be nested. If you specify only one + <var>number</var>, it will be assigned to both limits.</p> + + <div class="example"><h3>Example</h3><p><code> + LimitInternalRecursion 5 + </code></p></div> + +</div> +<div class="top"><a href="#page-header"><img alt="top" src="../images/up.gif" /></a></div> +<div class="directive-section"><h2><a name="LimitRequestBody" id="LimitRequestBody">LimitRequestBody</a> <a name="limitrequestbody" id="limitrequestbody">Directive</a></h2> +<table class="directive"> +<tr><th><a href="directive-dict.html#Description">Description:</a></th><td>Restricts the total size of the HTTP request body sent +from the client</td></tr> +<tr><th><a href="directive-dict.html#Syntax">Syntax:</a></th><td><code>LimitRequestBody <var>bytes</var></code></td></tr> +<tr><th><a href="directive-dict.html#Default">Default:</a></th><td><code>LimitRequestBody 0</code></td></tr> +<tr><th><a href="directive-dict.html#Context">Context:</a></th><td>server config, virtual host, directory, .htaccess</td></tr> +<tr><th><a href="directive-dict.html#Override">Override:</a></th><td>All</td></tr> +<tr><th><a href="directive-dict.html#Status">Status:</a></th><td>Core</td></tr> +<tr><th><a href="directive-dict.html#Module">Module:</a></th><td>core</td></tr> +</table> + <p>This directive specifies the number of <var>bytes</var> from 0 + (meaning unlimited) to 2147483647 (2GB) that are allowed in a + request body.</p> + + <p>The <code class="directive">LimitRequestBody</code> directive allows + the user to set a limit on the allowed size of an HTTP request + message body within the context in which the directive is given + (server, per-directory, per-file or per-location). If the client + request exceeds that limit, the server will return an error + response instead of servicing the request. The size of a normal + request message body will vary greatly depending on the nature of + the resource and the methods allowed on that resource. CGI scripts + typically use the message body for retrieving form information. + Implementations of the <code>PUT</code> method will require + a value at least as large as any representation that the server + wishes to accept for that resource.</p> + + <p>This directive gives the server administrator greater + control over abnormal client request behavior, which may be + useful for avoiding some forms of denial-of-service + attacks.</p> + + <p>If, for example, you are permitting file upload to a particular + location, and wish to limit the size of the uploaded file to 100K, + you might use the following directive:</p> + + <div class="example"><p><code> + LimitRequestBody 102400 + </code></p></div> + + +</div> +<div class="top"><a href="#page-header"><img alt="top" src="../images/up.gif" /></a></div> +<div class="directive-section"><h2><a name="LimitRequestFields" id="LimitRequestFields">LimitRequestFields</a> <a name="limitrequestfields" id="limitrequestfields">Directive</a></h2> +<table class="directive"> +<tr><th><a href="directive-dict.html#Description">Description:</a></th><td>Limits the number of HTTP request header fields that +will be accepted from the client</td></tr> +<tr><th><a href="directive-dict.html#Syntax">Syntax:</a></th><td><code>LimitRequestFields <var>number</var></code></td></tr> +<tr><th><a href="directive-dict.html#Default">Default:</a></th><td><code>LimitRequestFields 100</code></td></tr> +<tr><th><a href="directive-dict.html#Context">Context:</a></th><td>server config</td></tr> +<tr><th><a href="directive-dict.html#Status">Status:</a></th><td>Core</td></tr> +<tr><th><a href="directive-dict.html#Module">Module:</a></th><td>core</td></tr> +</table> + <p><var>Number</var> is an integer from 0 (meaning unlimited) to + 32767. The default value is defined by the compile-time + constant <code>DEFAULT_LIMIT_REQUEST_FIELDS</code> (100 as + distributed).</p> + + <p>The <code class="directive">LimitRequestFields</code> directive allows + the server administrator to modify the limit on the number of + request header fields allowed in an HTTP request. A server needs + this value to be larger than the number of fields that a normal + client request might include. The number of request header fields + used by a client rarely exceeds 20, but this may vary among + different client implementations, often depending upon the extent + to which a user has configured their browser to support detailed + content negotiation. Optional HTTP extensions are often expressed + using request header fields.</p> + + <p>This directive gives the server administrator greater + control over abnormal client request behavior, which may be + useful for avoiding some forms of denial-of-service attacks. + The value should be increased if normal clients see an error + response from the server that indicates too many fields were + sent in the request.</p> + + <p>For example:</p> + + <div class="example"><p><code> + LimitRequestFields 50 + </code></p></div> + + +</div> +<div class="top"><a href="#page-header"><img alt="top" src="../images/up.gif" /></a></div> +<div class="directive-section"><h2><a name="LimitRequestFieldSize" id="LimitRequestFieldSize">LimitRequestFieldSize</a> <a name="limitrequestfieldsize" id="limitrequestfieldsize">Directive</a></h2> +<table class="directive"> +<tr><th><a href="directive-dict.html#Description">Description:</a></th><td>Limits the size of the HTTP request header allowed from the +client</td></tr> +<tr><th><a href="directive-dict.html#Syntax">Syntax:</a></th><td><code>LimitRequestFieldsize <var>bytes</var></code></td></tr> +<tr><th><a href="directive-dict.html#Default">Default:</a></th><td><code>LimitRequestFieldsize 8190</code></td></tr> +<tr><th><a href="directive-dict.html#Context">Context:</a></th><td>server config</td></tr> +<tr><th><a href="directive-dict.html#Status">Status:</a></th><td>Core</td></tr> +<tr><th><a href="directive-dict.html#Module">Module:</a></th><td>core</td></tr> +</table> + <p>This directive specifies the number of <var>bytes</var> + that will be allowed in an HTTP request header.</p> + + <p>The <code class="directive">LimitRequestFieldSize</code> directive + allows the server administrator to reduce or increase the limit + on the allowed size of an HTTP request header field. A server + needs this value to be large enough to hold any one header field + from a normal client request. The size of a normal request header + field will vary greatly among different client implementations, + often depending upon the extent to which a user has configured + their browser to support detailed content negotiation. SPNEGO + authentication headers can be up to 12392 bytes.</p> + + <p>This directive gives the server administrator greater + control over abnormal client request behavior, which may be + useful for avoiding some forms of denial-of-service attacks.</p> + + <p>For example:</p> + + <div class="example"><p><code> + LimitRequestFieldSize 4094 + </code></p></div> + + <div class="note">Under normal conditions, the value should not be changed from + the default.</div> + + <div class="note">Apache 2.0.53 or higher is required for increasing the + limit above the compiled-in value of DEFAULT_LIMIT_REQUEST_FIELDSIZE + (8190 as distributed). + </div> + + +</div> +<div class="top"><a href="#page-header"><img alt="top" src="../images/up.gif" /></a></div> +<div class="directive-section"><h2><a name="LimitRequestLine" id="LimitRequestLine">LimitRequestLine</a> <a name="limitrequestline" id="limitrequestline">Directive</a></h2> +<table class="directive"> +<tr><th><a href="directive-dict.html#Description">Description:</a></th><td>Limit the size of the HTTP request line that will be accepted +from the client</td></tr> +<tr><th><a href="directive-dict.html#Syntax">Syntax:</a></th><td><code>LimitRequestLine <var>bytes</var></code></td></tr> +<tr><th><a href="directive-dict.html#Default">Default:</a></th><td><code>LimitRequestLine 8190</code></td></tr> +<tr><th><a href="directive-dict.html#Context">Context:</a></th><td>server config</td></tr> +<tr><th><a href="directive-dict.html#Status">Status:</a></th><td>Core</td></tr> +<tr><th><a href="directive-dict.html#Module">Module:</a></th><td>core</td></tr> +</table> + <p>This directive sets the number of <var>bytes</var> from 0 to + the value of the compile-time constant + <code>DEFAULT_LIMIT_REQUEST_LINE</code> (8190 as distributed) + that will be allowed on the HTTP request-line.</p> + + <p>The <code class="directive">LimitRequestLine</code> directive allows + the server administrator to reduce the limit on the allowed size + of a client's HTTP request-line below the normal input buffer size + compiled with the server. Since the request-line consists of the + HTTP method, URI, and protocol version, the + <code class="directive">LimitRequestLine</code> directive places a + restriction on the length of a request-URI allowed for a request + on the server. A server needs this value to be large enough to + hold any of its resource names, including any information that + might be passed in the query part of a <code>GET</code> request.</p> + + <p>This directive gives the server administrator greater + control over abnormal client request behavior, which may be + useful for avoiding some forms of denial-of-service attacks.</p> + + <p>For example:</p> + + <div class="example"><p><code> + LimitRequestLine 4094 + </code></p></div> + + <div class="note">Under normal conditions, the value should not be changed from + the default.</div> + +</div> +<div class="top"><a href="#page-header"><img alt="top" src="../images/up.gif" /></a></div> +<div class="directive-section"><h2><a name="LimitXMLRequestBody" id="LimitXMLRequestBody">LimitXMLRequestBody</a> <a name="limitxmlrequestbody" id="limitxmlrequestbody">Directive</a></h2> +<table class="directive"> +<tr><th><a href="directive-dict.html#Description">Description:</a></th><td>Limits the size of an XML-based request body</td></tr> +<tr><th><a href="directive-dict.html#Syntax">Syntax:</a></th><td><code>LimitXMLRequestBody <var>bytes</var></code></td></tr> +<tr><th><a href="directive-dict.html#Default">Default:</a></th><td><code>LimitXMLRequestBody 1000000</code></td></tr> +<tr><th><a href="directive-dict.html#Context">Context:</a></th><td>server config, virtual host, directory, .htaccess</td></tr> +<tr><th><a href="directive-dict.html#Override">Override:</a></th><td>All</td></tr> +<tr><th><a href="directive-dict.html#Status">Status:</a></th><td>Core</td></tr> +<tr><th><a href="directive-dict.html#Module">Module:</a></th><td>core</td></tr> +</table> + <p>Limit (in bytes) on maximum size of an XML-based request + body. A value of <code>0</code> will disable any checking.</p> + + <p>Example:</p> + + <div class="example"><p><code> + LimitXMLRequestBody 0 + </code></p></div> + + +</div> +<div class="top"><a href="#page-header"><img alt="top" src="../images/up.gif" /></a></div> +<div class="directive-section"><h2><a name="Location" id="Location"><Location></a> <a name="location" id="location">Directive</a></h2> +<table class="directive"> +<tr><th><a href="directive-dict.html#Description">Description:</a></th><td>Applies the enclosed directives only to matching +URLs</td></tr> +<tr><th><a href="directive-dict.html#Syntax">Syntax:</a></th><td><code><Location + <var>URL-path</var>|<var>URL</var>> ... </Location></code></td></tr> +<tr><th><a href="directive-dict.html#Context">Context:</a></th><td>server config, virtual host</td></tr> +<tr><th><a href="directive-dict.html#Status">Status:</a></th><td>Core</td></tr> +<tr><th><a href="directive-dict.html#Module">Module:</a></th><td>core</td></tr> +</table> + <p>The <code class="directive"><Location></code> directive + limits the scope of the enclosed directives by URL. It is similar to the + <code class="directive"><a href="#directory"><Directory></a></code> + directive, and starts a subsection which is terminated with a + <code></Location></code> directive. <code class="directive"><Location></code> sections are processed in the + order they appear in the configuration file, after the <code class="directive"><a href="#directory"><Directory></a></code> sections and + <code>.htaccess</code> files are read, and after the <code class="directive"><a href="#files"><Files></a></code> sections.</p> + + <p><code class="directive"><Location></code> sections operate + completely outside the filesystem. This has several consequences. + Most importantly, <code class="directive"><Location></code> + directives should not be used to control access to filesystem + locations. Since several different URLs may map to the same + filesystem location, such access controls may by circumvented.</p> + + <div class="note"><h3>When to use <code class="directive"><Location></code></h3> + + <p>Use <code class="directive"><Location></code> to apply + directives to content that lives outside the filesystem. For + content that lives in the filesystem, use <code class="directive"><a href="#directory"><Directory></a></code> and <code class="directive"><a href="#files"><Files></a></code>. An exception is + <code><Location /></code>, which is an easy way to + apply a configuration to the entire server.</p> + </div> + + <p>For all origin (non-proxy) requests, the URL to be matched is a + URL-path of the form <code>/path/</code>. No scheme, hostname, + port, or query string may be included. For proxy requests, the + URL to be matched is of the form + <code>scheme://servername/path</code>, and you must include the + prefix.</p> + + <p>The URL may use wildcards. In a wild-card string, <code>?</code> matches + any single character, and <code>*</code> matches any sequences of + characters.</p> + + <p>Extended regular + expressions can also be used, with the addition of the + <code>~</code> character. For example:</p> + + <div class="example"><p><code> + <Location ~ "/(extra|special)/data"> + </code></p></div> + + <p>would match URLs that contained the substring <code>/extra/data</code> + or <code>/special/data</code>. The directive <code class="directive"><a href="#locationmatch"><LocationMatch></a></code> behaves + identical to the regex version of <code class="directive"><Location></code>.</p> + + <p>The <code class="directive"><Location></code> + functionality is especially useful when combined with the + <code class="directive"><a href="#sethandler">SetHandler</a></code> + directive. For example, to enable status requests, but allow them + only from browsers at <code>foo.com</code>, you might use:</p> + + <div class="example"><p><code> + <Location /status><br /> + <span class="indent"> + SetHandler server-status<br /> + Order Deny,Allow<br /> + Deny from all<br /> + Allow from .foo.com<br /> + </span> + </Location> + </code></p></div> + + <div class="note"><h3>Note about / (slash)</h3> + <p>The slash character has special meaning depending on where in a + URL it appears. People may be used to its behavior in the filesystem + where multiple adjacent slashes are frequently collapsed to a single + slash (<em>i.e.</em>, <code>/home///foo</code> is the same as + <code>/home/foo</code>). In URL-space this is not necessarily true. + The <code class="directive"><a href="#locationmatch"><LocationMatch></a></code> + directive and the regex version of <code class="directive"><Location></code> require you to explicitly specify multiple + slashes if that is your intention.</p> + + <p>For example, <code><LocationMatch ^/abc></code> would match + the request URL <code>/abc</code> but not the request URL <code> + //abc</code>. The (non-regex) <code class="directive"><Location></code> directive behaves similarly when used for + proxy requests. But when (non-regex) <code class="directive"><Location></code> is used for non-proxy requests it will + implicitly match multiple slashes with a single slash. For example, + if you specify <code><Location /abc/def></code> and the + request is to <code>/abc//def</code> then it will match.</p> + </div> + +<h3>See also</h3> +<ul> +<li><a href="../sections.html">How <Directory>, <Location> + and <Files> sections work</a> for an explanation of how these + different sections are combined when a request is received</li> +</ul> +</div> +<div class="top"><a href="#page-header"><img alt="top" src="../images/up.gif" /></a></div> +<div class="directive-section"><h2><a name="LocationMatch" id="LocationMatch"><LocationMatch></a> <a name="locationmatch" id="locationmatch">Directive</a></h2> +<table class="directive"> +<tr><th><a href="directive-dict.html#Description">Description:</a></th><td>Applies the enclosed directives only to regular-expression +matching URLs</td></tr> +<tr><th><a href="directive-dict.html#Syntax">Syntax:</a></th><td><code><LocationMatch + <var>regex</var>> ... </LocationMatch></code></td></tr> +<tr><th><a href="directive-dict.html#Context">Context:</a></th><td>server config, virtual host</td></tr> +<tr><th><a href="directive-dict.html#Status">Status:</a></th><td>Core</td></tr> +<tr><th><a href="directive-dict.html#Module">Module:</a></th><td>core</td></tr> +</table> + <p>The <code class="directive"><LocationMatch></code> directive + limits the scope of the enclosed directives by URL, in an identical manner + to <code class="directive"><a href="#location"><Location></a></code>. However, + it takes a regular expression as an argument instead of a simple + string. For example:</p> + + <div class="example"><p><code> + <LocationMatch "/(extra|special)/data"> + </code></p></div> + + <p>would match URLs that contained the substring <code>/extra/data</code> + or <code>/special/data</code>.</p> + +<h3>See also</h3> +<ul> +<li><a href="../sections.html">How <Directory>, <Location> + and <Files> sections work</a> for an explanation of how these + different sections are combined when a request is received</li> +</ul> +</div> +<div class="top"><a href="#page-header"><img alt="top" src="../images/up.gif" /></a></div> +<div class="directive-section"><h2><a name="LogLevel" id="LogLevel">LogLevel</a> <a name="loglevel" id="loglevel">Directive</a></h2> +<table class="directive"> +<tr><th><a href="directive-dict.html#Description">Description:</a></th><td>Controls the verbosity of the ErrorLog</td></tr> +<tr><th><a href="directive-dict.html#Syntax">Syntax:</a></th><td><code>LogLevel <var>level</var></code></td></tr> +<tr><th><a href="directive-dict.html#Default">Default:</a></th><td><code>LogLevel warn</code></td></tr> +<tr><th><a href="directive-dict.html#Context">Context:</a></th><td>server config, virtual host</td></tr> +<tr><th><a href="directive-dict.html#Status">Status:</a></th><td>Core</td></tr> +<tr><th><a href="directive-dict.html#Module">Module:</a></th><td>core</td></tr> +</table> + <p><code class="directive">LogLevel</code> adjusts the verbosity of the + messages recorded in the error logs (see <code class="directive"><a href="#errorlog">ErrorLog</a></code> directive). The following + <var>level</var>s are available, in order of decreasing + significance:</p> + + <table class="bordered"> + + <tr> + <th><strong>Level</strong> </th> + + <th><strong>Description</strong> </th> + + <th><strong>Example</strong> </th> + </tr> + + <tr> + <td><code>emerg</code> </td> + + <td>Emergencies - system is unusable.</td> + + <td>"Child cannot open lock file. Exiting"</td> + </tr> + + <tr> + <td><code>alert</code> </td> + + <td>Action must be taken immediately.</td> + + <td>"getpwuid: couldn't determine user name from uid"</td> + </tr> + + <tr> + <td><code>crit</code> </td> + + <td>Critical Conditions.</td> + + <td>"socket: Failed to get a socket, exiting child"</td> + </tr> + + <tr> + <td><code>error</code> </td> + + <td>Error conditions.</td> + + <td>"Premature end of script headers"</td> + </tr> + + <tr> + <td><code>warn</code> </td> + + <td>Warning conditions.</td> + + <td>"child process 1234 did not exit, sending another + SIGHUP"</td> + </tr> + + <tr> + <td><code>notice</code> </td> + + <td>Normal but significant condition.</td> + + <td>"httpd: caught SIGBUS, attempting to dump core in + ..."</td> + </tr> + + <tr> + <td><code>info</code> </td> + + <td>Informational.</td> + + <td>"Server seems busy, (you may need to increase + StartServers, or Min/MaxSpareServers)..."</td> + </tr> + + <tr> + <td><code>debug</code> </td> + + <td>Debug-level messages</td> + + <td>"Opening config file ..."</td> + </tr> + </table> + + <p>When a particular level is specified, messages from all + other levels of higher significance will be reported as well. + <em>E.g.</em>, when <code>LogLevel info</code> is specified, + then messages with log levels of <code>notice</code> and + <code>warn</code> will also be posted.</p> + + <p>Using a level of at least <code>crit</code> is + recommended.</p> + + <p>For example:</p> + + <div class="example"><p><code> + LogLevel notice + </code></p></div> + + <div class="note"><h3>Note</h3> + <p>When logging to a regular file messages of the level + <code>notice</code> cannot be suppressed and thus are always + logged. However, this doesn't apply when logging is done + using <code>syslog</code>.</p> + </div> + +</div> +<div class="top"><a href="#page-header"><img alt="top" src="../images/up.gif" /></a></div> +<div class="directive-section"><h2><a name="MaxKeepAliveRequests" id="MaxKeepAliveRequests">MaxKeepAliveRequests</a> <a name="maxkeepaliverequests" id="maxkeepaliverequests">Directive</a></h2> +<table class="directive"> +<tr><th><a href="directive-dict.html#Description">Description:</a></th><td>Number of requests allowed on a persistent +connection</td></tr> +<tr><th><a href="directive-dict.html#Syntax">Syntax:</a></th><td><code>MaxKeepAliveRequests <var>number</var></code></td></tr> +<tr><th><a href="directive-dict.html#Default">Default:</a></th><td><code>MaxKeepAliveRequests 100</code></td></tr> +<tr><th><a href="directive-dict.html#Context">Context:</a></th><td>server config, virtual host</td></tr> +<tr><th><a href="directive-dict.html#Status">Status:</a></th><td>Core</td></tr> +<tr><th><a href="directive-dict.html#Module">Module:</a></th><td>core</td></tr> +</table> + <p>The <code class="directive">MaxKeepAliveRequests</code> directive + limits the number of requests allowed per connection when + <code class="directive"><a href="#keepalive">KeepAlive</a></code> is on. If it is + set to <code>0</code>, unlimited requests will be allowed. We + recommend that this setting be kept to a high value for maximum + server performance.</p> + + <p>For example:</p> + + <div class="example"><p><code> + MaxKeepAliveRequests 500 + </code></p></div> + +</div> +<div class="top"><a href="#page-header"><img alt="top" src="../images/up.gif" /></a></div> +<div class="directive-section"><h2><a name="NameVirtualHost" id="NameVirtualHost">NameVirtualHost</a> <a name="namevirtualhost" id="namevirtualhost">Directive</a></h2> +<table class="directive"> +<tr><th><a href="directive-dict.html#Description">Description:</a></th><td>Designates an IP address for name-virtual +hosting</td></tr> +<tr><th><a href="directive-dict.html#Syntax">Syntax:</a></th><td><code>NameVirtualHost <var>addr</var>[:<var>port</var>]</code></td></tr> +<tr><th><a href="directive-dict.html#Context">Context:</a></th><td>server config</td></tr> +<tr><th><a href="directive-dict.html#Status">Status:</a></th><td>Core</td></tr> +<tr><th><a href="directive-dict.html#Module">Module:</a></th><td>core</td></tr> +</table> + <p>The <code class="directive">NameVirtualHost</code> directive is a + required directive if you want to configure <a href="../vhosts/">name-based virtual hosts</a>.</p> + + <p>Although <var>addr</var> can be hostname it is recommended + that you always use an IP address, e.g.</p> + + <div class="example"><p><code> + NameVirtualHost 111.22.33.44 + </code></p></div> + + <p>With the <code class="directive">NameVirtualHost</code> directive you + specify the IP address on which the server will receive requests + for the name-based virtual hosts. This will usually be the address + to which your name-based virtual host names resolve. In cases + where a firewall or other proxy receives the requests and forwards + them on a different IP address to the server, you must specify the + IP address of the physical interface on the machine which will be + servicing the requests. If you have multiple name-based hosts on + multiple addresses, repeat the directive for each address.</p> + + <div class="note"><h3>Note</h3> + <p>Note, that the "main server" and any <code>_default_</code> servers + will <strong>never</strong> be served for a request to a + <code class="directive">NameVirtualHost</code> IP address (unless for some + reason you specify <code class="directive">NameVirtualHost</code> but then + don't define any <code class="directive">VirtualHost</code>s for that + address).</p> + </div> + + <p>Optionally you can specify a port number on which the + name-based virtual hosts should be used, e.g.</p> + + <div class="example"><p><code> + NameVirtualHost 111.22.33.44:8080 + </code></p></div> + + <p>IPv6 addresses must be enclosed in square brackets, as shown + in the following example:</p> + + <div class="example"><p><code> + NameVirtualHost [2001:db8::a00:20ff:fea7:ccea]:8080 + </code></p></div> + + <p>To receive requests on all interfaces, you can use an argument of + <code>*</code></p> + + <div class="example"><p><code> + NameVirtualHost * + </code></p></div> + + <div class="note"><h3>Argument to <code class="directive"><VirtualHost></code> + directive</h3> + <p>Note that the argument to the <code class="directive"><VirtualHost></code> directive must + exactly match the argument to the <code class="directive">NameVirtualHost</code> directive.</p> + + <div class="example"><p><code> + NameVirtualHost 1.2.3.4<br /> + <VirtualHost 1.2.3.4><br /> + # ...<br /> + </VirtualHost><br /> + </code></p></div> + </div> + +<h3>See also</h3> +<ul> +<li><a href="../vhosts/">Virtual Hosts +documentation</a></li> +</ul> +</div> +<div class="top"><a href="#page-header"><img alt="top" src="../images/up.gif" /></a></div> +<div class="directive-section"><h2><a name="Options" id="Options">Options</a> <a name="options" id="options">Directive</a></h2> +<table class="directive"> +<tr><th><a href="directive-dict.html#Description">Description:</a></th><td>Configures what features are available in a particular +directory</td></tr> +<tr><th><a href="directive-dict.html#Syntax">Syntax:</a></th><td><code>Options + [+|-]<var>option</var> [[+|-]<var>option</var>] ...</code></td></tr> +<tr><th><a href="directive-dict.html#Default">Default:</a></th><td><code>Options All</code></td></tr> +<tr><th><a href="directive-dict.html#Context">Context:</a></th><td>server config, virtual host, directory, .htaccess</td></tr> +<tr><th><a href="directive-dict.html#Override">Override:</a></th><td>Options</td></tr> +<tr><th><a href="directive-dict.html#Status">Status:</a></th><td>Core</td></tr> +<tr><th><a href="directive-dict.html#Module">Module:</a></th><td>core</td></tr> +</table> + <p>The <code class="directive">Options</code> directive controls which + server features are available in a particular directory.</p> + + <p><var>option</var> can be set to <code>None</code>, in which + case none of the extra features are enabled, or one or more of + the following:</p> + + <dl> + <dt><code>All</code></dt> + + <dd>All options except for <code>MultiViews</code>. This is the default + setting.</dd> + + <dt><code>ExecCGI</code></dt> + + <dd> + Execution of CGI scripts using <code class="module"><a href="../mod/mod_cgi.html">mod_cgi</a></code> + is permitted.</dd> + + <dt><code>FollowSymLinks</code></dt> + + <dd> + + The server will follow symbolic links in this directory. + <div class="note"> + <p>Even though the server follows the symlink it does <em>not</em> + change the pathname used to match against <code class="directive"><a href="#directory"><Directory></a></code> sections.</p> + <p>Note also, that this option <strong>gets ignored</strong> if set + inside a <code class="directive"><a href="#location"><Location></a></code> + section.</p> + </div></dd> + + <dt><code>Includes</code></dt> + + <dd> + Server-side includes provided by <code class="module"><a href="../mod/mod_include.html">mod_include</a></code> + are permitted.</dd> + + <dt><code>IncludesNOEXEC</code></dt> + + <dd> + + Server-side includes are permitted, but the <code>#exec + cmd</code> and <code>#exec cgi</code> are disabled. It is still + possible to <code>#include virtual</code> CGI scripts from + <code class="directive"><a href="../mod/mod_alias.html#scriptalias">ScriptAlias</a></code>ed + directories.</dd> + + <dt><code>Indexes</code></dt> + + <dd> + If a URL which maps to a directory is requested, and there + is no <code class="directive"><a href="../mod/mod_dir.html#directoryindex">DirectoryIndex</a></code> + (<em>e.g.</em>, <code>index.html</code>) in that directory, then + <code class="module"><a href="../mod/mod_autoindex.html">mod_autoindex</a></code> will return a formatted listing + of the directory.</dd> + + <dt><code>MultiViews</code></dt> + + <dd> + <a href="../content-negotiation.html">Content negotiated</a> + "MultiViews" are allowed using + <code class="module"><a href="../mod/mod_negotiation.html">mod_negotiation</a></code>.</dd> + + <dt><code>SymLinksIfOwnerMatch</code></dt> + + <dd>The server will only follow symbolic links for which the + target file or directory is owned by the same user id as the + link. + + <div class="note"><h3>Note</h3> This option gets ignored if + set inside a <code class="directive"><a href="#location"><Location></a></code> section.</div> + </dd> + </dl> + + <p>Normally, if multiple <code class="directive">Options</code> could + apply to a directory, then the most specific one is used and + others are ignored; the options are not merged. (See <a href="../sections.html#mergin">how sections are merged</a>.) + However if <em>all</em> the options on the + <code class="directive">Options</code> directive are preceded by a + <code>+</code> or <code>-</code> symbol, the options are + merged. Any options preceded by a <code>+</code> are added to the + options currently in force, and any options preceded by a + <code>-</code> are removed from the options currently in + force. </p> + + <div class="warning"><h3>Warning</h3> + <p>Mixing <code class="directive">Options</code> with a <code>+</code> or + <code>-</code> with those without is not valid syntax, and is likely + to cause unexpected results.</p> + </div> + + <p>For example, without any <code>+</code> and <code>-</code> symbols:</p> + + <div class="example"><p><code> + <Directory /web/docs><br /> + <span class="indent"> + Options Indexes FollowSymLinks<br /> + </span> + </Directory><br /> + <br /> + <Directory /web/docs/spec><br /> + <span class="indent"> + Options Includes<br /> + </span> + </Directory> + </code></p></div> + + <p>then only <code>Includes</code> will be set for the + <code>/web/docs/spec</code> directory. However if the second + <code class="directive">Options</code> directive uses the <code>+</code> and + <code>-</code> symbols:</p> + + <div class="example"><p><code> + <Directory /web/docs><br /> + <span class="indent"> + Options Indexes FollowSymLinks<br /> + </span> + </Directory><br /> + <br /> + <Directory /web/docs/spec><br /> + <span class="indent"> + Options +Includes -Indexes<br /> + </span> + </Directory> + </code></p></div> + + <p>then the options <code>FollowSymLinks</code> and + <code>Includes</code> are set for the <code>/web/docs/spec</code> + directory.</p> + + <div class="note"><h3>Note</h3> + <p>Using <code>-IncludesNOEXEC</code> or + <code>-Includes</code> disables server-side includes completely + regardless of the previous setting.</p> + </div> + + <p>The default in the absence of any other settings is + <code>All</code>.</p> + +</div> +<div class="top"><a href="#page-header"><img alt="top" src="../images/up.gif" /></a></div> +<div class="directive-section"><h2><a name="Require" id="Require">Require</a> <a name="require" id="require">Directive</a></h2> +<table class="directive"> +<tr><th><a href="directive-dict.html#Description">Description:</a></th><td>Selects which authenticated users can access +a resource</td></tr> +<tr><th><a href="directive-dict.html#Syntax">Syntax:</a></th><td><code>Require <var>entity-name</var> [<var>entity-name</var>] ...</code></td></tr> +<tr><th><a href="directive-dict.html#Context">Context:</a></th><td>directory, .htaccess</td></tr> +<tr><th><a href="directive-dict.html#Override">Override:</a></th><td>AuthConfig</td></tr> +<tr><th><a href="directive-dict.html#Status">Status:</a></th><td>Core</td></tr> +<tr><th><a href="directive-dict.html#Module">Module:</a></th><td>core</td></tr> +</table> + <p>This directive selects which authenticated users can access + a resource. The allowed syntaxes are:</p> + + <dl> + <dt><code>Require user <var>userid</var> [<var>userid</var>] + ...</code></dt> + <dd>Only the named users can access the resource.</dd> + + <dt><code>Require group <var>group-name</var> [<var>group-name</var>] + ...</code></dt> + <dd>Only users in the named groups can access the resource.</dd> + + <dt><code>Require valid-user</code></dt> + <dd>All valid users can access the resource.</dd> + </dl> + + <p><code class="directive">Require</code> must be accompanied by + <code class="directive"><a href="#authname">AuthName</a></code> and <code class="directive"><a href="#authtype">AuthType</a></code> directives, and directives such + as <code class="directive"><a href="../mod/mod_auth.html#authuserfile">AuthUserFile</a></code> + and <code class="directive"><a href="../mod/mod_auth.html#authgroupfile">AuthGroupFile</a></code> (to + define users and groups) in order to work correctly. Example:</p> + + <div class="example"><p><code> + AuthType Basic<br /> + AuthName "Restricted Resource"<br /> + AuthUserFile /web/users<br /> + AuthGroupFile /web/groups<br /> + Require group admin + </code></p></div> + + <p>Access controls which are applied in this way are effective for + <strong>all</strong> methods. <strong>This is what is normally + desired.</strong> If you wish to apply access controls only to + specific methods, while leaving other methods unprotected, then + place the <code class="directive">Require</code> statement into a + <code class="directive"><a href="#limit"><Limit></a></code> + section.</p> + +<h3>See also</h3> +<ul> +<li><code class="directive"><a href="#satisfy">Satisfy</a></code></li> +<li><code class="module"><a href="../mod/mod_access.html">mod_access</a></code></li> +</ul> +</div> +<div class="top"><a href="#page-header"><img alt="top" src="../images/up.gif" /></a></div> +<div class="directive-section"><h2><a name="RLimitCPU" id="RLimitCPU">RLimitCPU</a> <a name="rlimitcpu" id="rlimitcpu">Directive</a></h2> +<table class="directive"> +<tr><th><a href="directive-dict.html#Description">Description:</a></th><td>Limits the CPU consumption of processes launched +by Apache children</td></tr> +<tr><th><a href="directive-dict.html#Syntax">Syntax:</a></th><td><code>RLimitCPU <var>seconds</var>|max [<var>seconds</var>|max]</code></td></tr> +<tr><th><a href="directive-dict.html#Default">Default:</a></th><td><code>Unset; uses operating system defaults</code></td></tr> +<tr><th><a href="directive-dict.html#Context">Context:</a></th><td>server config, virtual host, directory, .htaccess</td></tr> +<tr><th><a href="directive-dict.html#Override">Override:</a></th><td>All</td></tr> +<tr><th><a href="directive-dict.html#Status">Status:</a></th><td>Core</td></tr> +<tr><th><a href="directive-dict.html#Module">Module:</a></th><td>core</td></tr> +</table> + <p>Takes 1 or 2 parameters. The first parameter sets the soft + resource limit for all processes and the second parameter sets + the maximum resource limit. Either parameter can be a number, + or <code>max</code> to indicate to the server that the limit should + be set to the maximum allowed by the operating system + configuration. Raising the maximum resource limit requires that + the server is running as <code>root</code>, or in the initial startup + phase.</p> + + <p>This applies to processes forked off from Apache children + servicing requests, not the Apache children themselves. This + includes CGI scripts and SSI exec commands, but not any + processes forked off from the Apache parent such as piped + logs.</p> + + <p>CPU resource limits are expressed in seconds per + process.</p> + +<h3>See also</h3> +<ul> +<li><code class="directive"><a href="#rlimitmem">RLimitMEM</a></code></li> +<li><code class="directive"><a href="#rlimitnproc">RLimitNPROC</a></code></li> +</ul> +</div> +<div class="top"><a href="#page-header"><img alt="top" src="../images/up.gif" /></a></div> +<div class="directive-section"><h2><a name="RLimitMEM" id="RLimitMEM">RLimitMEM</a> <a name="rlimitmem" id="rlimitmem">Directive</a></h2> +<table class="directive"> +<tr><th><a href="directive-dict.html#Description">Description:</a></th><td>Limits the memory consumption of processes launched +by Apache children</td></tr> +<tr><th><a href="directive-dict.html#Syntax">Syntax:</a></th><td><code>RLimitMEM <var>bytes</var>|max [<var>bytes</var>|max]</code></td></tr> +<tr><th><a href="directive-dict.html#Default">Default:</a></th><td><code>Unset; uses operating system defaults</code></td></tr> +<tr><th><a href="directive-dict.html#Context">Context:</a></th><td>server config, virtual host, directory, .htaccess</td></tr> +<tr><th><a href="directive-dict.html#Override">Override:</a></th><td>All</td></tr> +<tr><th><a href="directive-dict.html#Status">Status:</a></th><td>Core</td></tr> +<tr><th><a href="directive-dict.html#Module">Module:</a></th><td>core</td></tr> +</table> + <p>Takes 1 or 2 parameters. The first parameter sets the soft + resource limit for all processes and the second parameter sets + the maximum resource limit. Either parameter can be a number, + or <code>max</code> to indicate to the server that the limit should + be set to the maximum allowed by the operating system + configuration. Raising the maximum resource limit requires that + the server is running as <code>root</code>, or in the initial startup + phase.</p> + + <p>This applies to processes forked off from Apache children + servicing requests, not the Apache children themselves. This + includes CGI scripts and SSI exec commands, but not any + processes forked off from the Apache parent such as piped + logs.</p> + + <p>Memory resource limits are expressed in bytes per + process.</p> + +<h3>See also</h3> +<ul> +<li><code class="directive"><a href="#rlimitcpu">RLimitCPU</a></code></li> +<li><code class="directive"><a href="#rlimitnproc">RLimitNPROC</a></code></li> +</ul> +</div> +<div class="top"><a href="#page-header"><img alt="top" src="../images/up.gif" /></a></div> +<div class="directive-section"><h2><a name="RLimitNPROC" id="RLimitNPROC">RLimitNPROC</a> <a name="rlimitnproc" id="rlimitnproc">Directive</a></h2> +<table class="directive"> +<tr><th><a href="directive-dict.html#Description">Description:</a></th><td>Limits the number of processes that can be launched by +processes launched by Apache children</td></tr> +<tr><th><a href="directive-dict.html#Syntax">Syntax:</a></th><td><code>RLimitNPROC <var>number</var>|max [<var>number</var>|max]</code></td></tr> +<tr><th><a href="directive-dict.html#Default">Default:</a></th><td><code>Unset; uses operating system defaults</code></td></tr> +<tr><th><a href="directive-dict.html#Context">Context:</a></th><td>server config, virtual host, directory, .htaccess</td></tr> +<tr><th><a href="directive-dict.html#Override">Override:</a></th><td>All</td></tr> +<tr><th><a href="directive-dict.html#Status">Status:</a></th><td>Core</td></tr> +<tr><th><a href="directive-dict.html#Module">Module:</a></th><td>core</td></tr> +</table> + <p>Takes 1 or 2 parameters. The first parameter sets the soft + resource limit for all processes and the second parameter sets + the maximum resource limit. Either parameter can be a number, + or <code>max</code> to indicate to the server that the limit + should be set to the maximum allowed by the operating system + configuration. Raising the maximum resource limit requires that + the server is running as <code>root</code>, or in the initial startup + phase.</p> + + <p>This applies to processes forked off from Apache children + servicing requests, not the Apache children themselves. This + includes CGI scripts and SSI exec commands, but not any + processes forked off from the Apache parent such as piped + logs.</p> + + <p>Process limits control the number of processes per user.</p> + + <div class="note"><h3>Note</h3> + <p>If CGI processes are <strong>not</strong> running + under user ids other than the web server user id, this directive + will limit the number of processes that the server itself can + create. Evidence of this situation will be indicated by + <strong><code>cannot fork</code></strong> messages in the + <code>error_log</code>.</p> + </div> + +<h3>See also</h3> +<ul> +<li><code class="directive"><a href="#rlimitmem">RLimitMEM</a></code></li> +<li><code class="directive"><a href="#rlimitcpu">RLimitCPU</a></code></li> +</ul> +</div> +<div class="top"><a href="#page-header"><img alt="top" src="../images/up.gif" /></a></div> +<div class="directive-section"><h2><a name="Satisfy" id="Satisfy">Satisfy</a> <a name="satisfy" id="satisfy">Directive</a></h2> +<table class="directive"> +<tr><th><a href="directive-dict.html#Description">Description:</a></th><td>Interaction between host-level access control and +user authentication</td></tr> +<tr><th><a href="directive-dict.html#Syntax">Syntax:</a></th><td><code>Satisfy Any|All</code></td></tr> +<tr><th><a href="directive-dict.html#Default">Default:</a></th><td><code>Satisfy All</code></td></tr> +<tr><th><a href="directive-dict.html#Context">Context:</a></th><td>directory, .htaccess</td></tr> +<tr><th><a href="directive-dict.html#Override">Override:</a></th><td>AuthConfig</td></tr> +<tr><th><a href="directive-dict.html#Status">Status:</a></th><td>Core</td></tr> +<tr><th><a href="directive-dict.html#Module">Module:</a></th><td>core</td></tr> +<tr><th><a href="directive-dict.html#Compatibility">Compatibility:</a></th><td>Influenced by <code class="directive"><a href="#limit"><Limit></a></code> and <code class="directive"><a href="#limitexcept"><LimitExcept></a></code> in version 2.0.51 and +later</td></tr> +</table> + <p>Access policy if both <code class="directive"><a href="../mod/mod_access.html#allow">Allow</a></code> and <code class="directive"><a href="#require">Require</a></code> used. The parameter can be + either <code>All</code> or <code>Any</code>. This directive is only + useful if access to a particular area is being restricted by both + username/password <em>and</em> client host address. In this case + the default behavior (<code>All</code>) is to require that the client + passes the address access restriction <em>and</em> enters a valid + username and password. With the <code>Any</code> option the client will be + granted access if they either pass the host restriction or enter a + valid username and password. This can be used to password restrict + an area, but to let clients from particular addresses in without + prompting for a password.</p> + + <p>For example, if you wanted to let people on your network have + unrestricted access to a portion of your website, but require that + people outside of your network provide a password, you could use a + configuration similar to the following:</p> + + <div class="example"><p><code> + Require valid-user<br /> + Allow from 192.168.1<br /> + Satisfy Any + </code></p></div> + + <p>Since version 2.0.51 <code class="directive">Satisfy</code> directives can + be restricted to particular methods by <code class="directive"><a href="#limit"><Limit></a></code> and <code class="directive"><a href="#limitexcept"><LimitExcept></a></code> sections.</p> + +<h3>See also</h3> +<ul> +<li><code class="directive"><a href="../mod/mod_access.html#allow">Allow</a></code></li> +<li><code class="directive"><a href="#require">Require</a></code></li> +</ul> +</div> +<div class="top"><a href="#page-header"><img alt="top" src="../images/up.gif" /></a></div> +<div class="directive-section"><h2><a name="ScriptInterpreterSource" id="ScriptInterpreterSource">ScriptInterpreterSource</a> <a name="scriptinterpretersource" id="scriptinterpretersource">Directive</a></h2> +<table class="directive"> +<tr><th><a href="directive-dict.html#Description">Description:</a></th><td>Technique for locating the interpreter for CGI +scripts</td></tr> +<tr><th><a href="directive-dict.html#Syntax">Syntax:</a></th><td><code>ScriptInterpreterSource Registry|Registry-Strict|Script</code></td></tr> +<tr><th><a href="directive-dict.html#Default">Default:</a></th><td><code>ScriptInterpreterSource Script</code></td></tr> +<tr><th><a href="directive-dict.html#Context">Context:</a></th><td>server config, virtual host, directory, .htaccess</td></tr> +<tr><th><a href="directive-dict.html#Override">Override:</a></th><td>FileInfo</td></tr> +<tr><th><a href="directive-dict.html#Status">Status:</a></th><td>Core</td></tr> +<tr><th><a href="directive-dict.html#Module">Module:</a></th><td>core</td></tr> +<tr><th><a href="directive-dict.html#Compatibility">Compatibility:</a></th><td>Win32 only; +option <code>Registry-Strict</code> is available in Apache 2.0 and +later</td></tr> +</table> + <p>This directive is used to control how Apache finds the + interpreter used to run CGI scripts. The default setting is + <code>Script</code>. This causes Apache to use the interpreter pointed to + by the shebang line (first line, starting with <code>#!</code>) in the + script. On Win32 systems this line usually looks like:</p> + + <div class="example"><p><code> + #!C:/Perl/bin/perl.exe + </code></p></div> + + <p>or, if <code>perl</code> is in the <code>PATH</code>, simply:</p> + + <div class="example"><p><code> + #!perl + </code></p></div> + + <p>Setting <code>ScriptInterpreterSource Registry</code> will + cause the Windows Registry tree <code>HKEY_CLASSES_ROOT</code> to be + searched using the script file extension (e.g., <code>.pl</code>) as a + search key. The command defined by the registry subkey + <code>Shell\ExecCGI\Command</code> or, if it does not exist, by the subkey + <code>Shell\Open\Command</code> is used to open the script file. If the + registry keys cannot be found, Apache falls back to the behavior of the + <code>Script</code> option.</p> + + <div class="warning"><h3>Security</h3> + <p>Be careful when using <code>ScriptInterpreterSource + Registry</code> with <code class="directive"><a href="../mod/mod_alias.html#scriptalias">ScriptAlias</a></code>'ed directories, because + Apache will try to execute <strong>every</strong> file within this + directory. The <code>Registry</code> setting may cause undesired + program calls on files which are typically not executed. For + example, the default open command on <code>.htm</code> files on + most Windows systems will execute Microsoft Internet Explorer, so + any HTTP request for an <code>.htm</code> file existing within the + script directory would start the browser in the background on the + server. This is a good way to crash your system within a minute or + so.</p> + </div> + + <p>The option <code>Registry-Strict</code> which is new in Apache + 2.0 does the same thing as <code>Registry</code> but uses only the + subkey <code>Shell\ExecCGI\Command</code>. The + <code>ExecCGI</code> key is not a common one. It must be + configured manually in the windows registry and hence prevents + accidental program calls on your system.</p> + +</div> +<div class="top"><a href="#page-header"><img alt="top" src="../images/up.gif" /></a></div> +<div class="directive-section"><h2><a name="ServerAdmin" id="ServerAdmin">ServerAdmin</a> <a name="serveradmin" id="serveradmin">Directive</a></h2> +<table class="directive"> +<tr><th><a href="directive-dict.html#Description">Description:</a></th><td>Email address that the server includes in error +messages sent to the client</td></tr> +<tr><th><a href="directive-dict.html#Syntax">Syntax:</a></th><td><code>ServerAdmin <var>email-address</var></code></td></tr> +<tr><th><a href="directive-dict.html#Context">Context:</a></th><td>server config, virtual host</td></tr> +<tr><th><a href="directive-dict.html#Status">Status:</a></th><td>Core</td></tr> +<tr><th><a href="directive-dict.html#Module">Module:</a></th><td>core</td></tr> +</table> + <p>The <code class="directive">ServerAdmin</code> sets the e-mail address + that the server includes in any error messages it returns to the + client.</p> + + <p>It may be worth setting up a dedicated address for this, e.g.</p> + + <div class="example"><p><code> + ServerAdmin www-admin@foo.example.com + </code></p></div> + <p>as users do not always mention that they are talking about the + server!</p> + +</div> +<div class="top"><a href="#page-header"><img alt="top" src="../images/up.gif" /></a></div> +<div class="directive-section"><h2><a name="ServerAlias" id="ServerAlias">ServerAlias</a> <a name="serveralias" id="serveralias">Directive</a></h2> +<table class="directive"> +<tr><th><a href="directive-dict.html#Description">Description:</a></th><td>Alternate names for a host used when matching requests +to name-virtual hosts</td></tr> +<tr><th><a href="directive-dict.html#Syntax">Syntax:</a></th><td><code>ServerAlias <var>hostname</var> [<var>hostname</var>] ...</code></td></tr> +<tr><th><a href="directive-dict.html#Context">Context:</a></th><td>virtual host</td></tr> +<tr><th><a href="directive-dict.html#Status">Status:</a></th><td>Core</td></tr> +<tr><th><a href="directive-dict.html#Module">Module:</a></th><td>core</td></tr> +</table> + <p>The <code class="directive">ServerAlias</code> directive sets the + alternate names for a host, for use with <a href="../vhosts/name-based.html">name-based virtual hosts</a>.</p> + + <div class="example"><p><code> + <VirtualHost *><br /> + ServerName server.domain.com<br /> + ServerAlias server server2.domain.com server2<br /> + # ...<br /> + </VirtualHost> + </code></p></div> + +<h3>See also</h3> +<ul> +<li><a href="../vhosts/">Apache Virtual Host documentation</a></li> +</ul> +</div> +<div class="top"><a href="#page-header"><img alt="top" src="../images/up.gif" /></a></div> +<div class="directive-section"><h2><a name="ServerName" id="ServerName">ServerName</a> <a name="servername" id="servername">Directive</a></h2> +<table class="directive"> +<tr><th><a href="directive-dict.html#Description">Description:</a></th><td>Hostname and port that the server uses to identify +itself</td></tr> +<tr><th><a href="directive-dict.html#Syntax">Syntax:</a></th><td><code>ServerName <var>fully-qualified-domain-name</var>[:<var>port</var>]</code></td></tr> +<tr><th><a href="directive-dict.html#Context">Context:</a></th><td>server config, virtual host</td></tr> +<tr><th><a href="directive-dict.html#Status">Status:</a></th><td>Core</td></tr> +<tr><th><a href="directive-dict.html#Module">Module:</a></th><td>core</td></tr> +<tr><th><a href="directive-dict.html#Compatibility">Compatibility:</a></th><td>In version 2.0, this + directive supersedes the functionality of the <code class="directive">Port</code> + directive from version 1.3.</td></tr> +</table> + <p>The <code class="directive">ServerName</code> directive sets the hostname and + port that the server uses to identify itself. This is used when + creating redirection URLs. For example, if the name of the + machine hosting the web server is <code>simple.example.com</code>, + but the machine also has the DNS alias <code>www.example.com</code> + and you wish the web server to be so identified, the following + directive should be used:</p> + + <div class="example"><p><code> + ServerName www.example.com:80 + </code></p></div> + + <p>If no <code class="directive">ServerName</code> is specified, then the + server attempts to deduce the hostname by performing a reverse + lookup on the IP address. If no port is specified in the + <code class="directive">ServerName</code>, then the server will use the port + from the incoming + request. For optimal reliability and predictability, you should + specify an explicit hostname and port using the + <code class="directive">ServerName</code> directive.</p> + + <p>If you are using <a href="../vhosts/name-based.html">name-based virtual hosts</a>, + the <code class="directive">ServerName</code> inside a + <code class="directive"><a href="#virtualhost"><VirtualHost></a></code> + section specifies what hostname must appear in the request's + <code>Host:</code> header to match this virtual host.</p> + + <p>See the description of the + <code class="directive"><a href="#usecanonicalname">UseCanonicalName</a></code> directive for + settings which determine whether self-referential URL's (e.g., by the + <code class="module"><a href="../mod/mod_dir.html">mod_dir</a></code> module) will refer to the + specified port, or to the port number given in the client's request. + </p> + +<h3>See also</h3> +<ul> +<li><a href="../dns-caveats.html">Issues Regarding DNS and + Apache</a></li> +<li><a href="../vhosts/">Apache virtual host + documentation</a></li> +<li><code class="directive"><a href="#usecanonicalname">UseCanonicalName</a></code></li> +<li><code class="directive"><a href="#namevirtualhost">NameVirtualHost</a></code></li> +<li><code class="directive"><a href="#serveralias">ServerAlias</a></code></li> +</ul> +</div> +<div class="top"><a href="#page-header"><img alt="top" src="../images/up.gif" /></a></div> +<div class="directive-section"><h2><a name="ServerPath" id="ServerPath">ServerPath</a> <a name="serverpath" id="serverpath">Directive</a></h2> +<table class="directive"> +<tr><th><a href="directive-dict.html#Description">Description:</a></th><td>Legacy URL pathname for a name-based virtual host that +is accessed by an incompatible browser</td></tr> +<tr><th><a href="directive-dict.html#Syntax">Syntax:</a></th><td><code>ServerPath <var>URL-path</var></code></td></tr> +<tr><th><a href="directive-dict.html#Context">Context:</a></th><td>virtual host</td></tr> +<tr><th><a href="directive-dict.html#Status">Status:</a></th><td>Core</td></tr> +<tr><th><a href="directive-dict.html#Module">Module:</a></th><td>core</td></tr> +</table> + <p>The <code class="directive">ServerPath</code> directive sets the legacy + URL pathname for a host, for use with <a href="../vhosts/">name-based virtual hosts</a>.</p> + +<h3>See also</h3> +<ul> +<li><a href="../vhosts/">Apache Virtual Host documentation</a></li> +</ul> +</div> +<div class="top"><a href="#page-header"><img alt="top" src="../images/up.gif" /></a></div> +<div class="directive-section"><h2><a name="ServerRoot" id="ServerRoot">ServerRoot</a> <a name="serverroot" id="serverroot">Directive</a></h2> +<table class="directive"> +<tr><th><a href="directive-dict.html#Description">Description:</a></th><td>Base directory for the server installation</td></tr> +<tr><th><a href="directive-dict.html#Syntax">Syntax:</a></th><td><code>ServerRoot <var>directory-path</var></code></td></tr> +<tr><th><a href="directive-dict.html#Default">Default:</a></th><td><code>ServerRoot /usr/local/apache</code></td></tr> +<tr><th><a href="directive-dict.html#Context">Context:</a></th><td>server config</td></tr> +<tr><th><a href="directive-dict.html#Status">Status:</a></th><td>Core</td></tr> +<tr><th><a href="directive-dict.html#Module">Module:</a></th><td>core</td></tr> +</table> + <p>The <code class="directive">ServerRoot</code> directive sets the + directory in which the server lives. Typically it will contain the + subdirectories <code>conf/</code> and <code>logs/</code>. Relative + paths in other configuration directives (such as <code class="directive"><a href="#include">Include</a></code> or <code class="directive"><a href="../mod/mod_so.html#loadmodule">LoadModule</a></code>, for example) are taken as + relative to this directory.</p> + + <div class="example"><h3>Example</h3><p><code> + ServerRoot /home/httpd + </code></p></div> + + +<h3>See also</h3> +<ul> +<li><a href="../invoking.html">the <code>-d</code> + option to <code>httpd</code></a></li> +<li><a href="../misc/security_tips.html#serverroot">the + security tips</a> for information on how to properly set + permissions on the <code class="directive">ServerRoot</code></li> +</ul> +</div> +<div class="top"><a href="#page-header"><img alt="top" src="../images/up.gif" /></a></div> +<div class="directive-section"><h2><a name="ServerSignature" id="ServerSignature">ServerSignature</a> <a name="serversignature" id="serversignature">Directive</a></h2> +<table class="directive"> +<tr><th><a href="directive-dict.html#Description">Description:</a></th><td>Configures the footer on server-generated documents</td></tr> +<tr><th><a href="directive-dict.html#Syntax">Syntax:</a></th><td><code>ServerSignature On|Off|EMail</code></td></tr> +<tr><th><a href="directive-dict.html#Default">Default:</a></th><td><code>ServerSignature Off</code></td></tr> +<tr><th><a href="directive-dict.html#Context">Context:</a></th><td>server config, virtual host, directory, .htaccess</td></tr> +<tr><th><a href="directive-dict.html#Override">Override:</a></th><td>All</td></tr> +<tr><th><a href="directive-dict.html#Status">Status:</a></th><td>Core</td></tr> +<tr><th><a href="directive-dict.html#Module">Module:</a></th><td>core</td></tr> +</table> + <p>The <code class="directive">ServerSignature</code> directive allows the + configuration of a trailing footer line under server-generated + documents (error messages, <code class="module"><a href="../mod/mod_proxy.html">mod_proxy</a></code> ftp directory + listings, <code class="module"><a href="../mod/mod_info.html">mod_info</a></code> output, ...). The reason why you + would want to enable such a footer line is that in a chain of proxies, + the user often has no possibility to tell which of the chained servers + actually produced a returned error message.</p> + + <p>The <code>Off</code> + setting, which is the default, suppresses the footer line (and is + therefore compatible with the behavior of Apache-1.2 and + below). The <code>On</code> setting simply adds a line with the + server version number and <code class="directive"><a href="#servername">ServerName</a></code> of the serving virtual host, + and the <code>EMail</code> setting additionally creates a + "mailto:" reference to the <code class="directive"><a href="#serveradmin">ServerAdmin</a></code> of the referenced + document.</p> + + <p>After version 2.0.44, the details of the server version number + presented are controlled by the <code class="directive"><a href="#servertokens">ServerTokens</a></code> directive.</p> + +<h3>See also</h3> +<ul> +<li><code class="directive"><a href="#servertokens">ServerTokens</a></code></li> +</ul> +</div> +<div class="top"><a href="#page-header"><img alt="top" src="../images/up.gif" /></a></div> +<div class="directive-section"><h2><a name="ServerTokens" id="ServerTokens">ServerTokens</a> <a name="servertokens" id="servertokens">Directive</a></h2> +<table class="directive"> +<tr><th><a href="directive-dict.html#Description">Description:</a></th><td>Configures the <code>Server</code> HTTP response +header</td></tr> +<tr><th><a href="directive-dict.html#Syntax">Syntax:</a></th><td><code>ServerTokens Major|Minor|Min[imal]|Prod[uctOnly]|OS|Full</code></td></tr> +<tr><th><a href="directive-dict.html#Default">Default:</a></th><td><code>ServerTokens Full</code></td></tr> +<tr><th><a href="directive-dict.html#Context">Context:</a></th><td>server config</td></tr> +<tr><th><a href="directive-dict.html#Status">Status:</a></th><td>Core</td></tr> +<tr><th><a href="directive-dict.html#Module">Module:</a></th><td>core</td></tr> +</table> + <p>This directive controls whether <code>Server</code> response + header field which is sent back to clients includes a + description of the generic OS-type of the server as well as + information about compiled-in modules.</p> + + <dl> + <dt><code>ServerTokens Prod[uctOnly]</code></dt> + + <dd>Server sends (<em>e.g.</em>): <code>Server: + Apache</code></dd> + + <dt><code>ServerTokens Major</code></dt> + + <dd>Server sends (<em>e.g.</em>): <code>Server: + Apache/2</code></dd> + + <dt><code>ServerTokens Minor</code></dt> + + <dd>Server sends (<em>e.g.</em>): <code>Server: + Apache/2.0</code></dd> + + <dt><code>ServerTokens Min[imal]</code></dt> + + <dd>Server sends (<em>e.g.</em>): <code>Server: + Apache/2.0.41</code></dd> + + <dt><code>ServerTokens OS</code></dt> + + <dd>Server sends (<em>e.g.</em>): <code>Server: Apache/2.0.41 + (Unix)</code></dd> + + <dt><code>ServerTokens Full</code> (or not specified)</dt> + + <dd>Server sends (<em>e.g.</em>): <code>Server: Apache/2.0.41 + (Unix) PHP/4.2.2 MyMod/1.2</code></dd> + </dl> + + <p>This setting applies to the entire server, and cannot be + enabled or disabled on a virtualhost-by-virtualhost basis.</p> + + <p>After version 2.0.44, this directive also controls the + information presented by the <code class="directive"><a href="#serversignature">ServerSignature</a></code> directive.</p> + +<h3>See also</h3> +<ul> +<li><code class="directive"><a href="#serversignature">ServerSignature</a></code></li> +</ul> +</div> +<div class="top"><a href="#page-header"><img alt="top" src="../images/up.gif" /></a></div> +<div class="directive-section"><h2><a name="SetHandler" id="SetHandler">SetHandler</a> <a name="sethandler" id="sethandler">Directive</a></h2> +<table class="directive"> +<tr><th><a href="directive-dict.html#Description">Description:</a></th><td>Forces all matching files to be processed by a +handler</td></tr> +<tr><th><a href="directive-dict.html#Syntax">Syntax:</a></th><td><code>SetHandler <var>handler-name</var>|None</code></td></tr> +<tr><th><a href="directive-dict.html#Context">Context:</a></th><td>server config, virtual host, directory, .htaccess</td></tr> +<tr><th><a href="directive-dict.html#Override">Override:</a></th><td>FileInfo</td></tr> +<tr><th><a href="directive-dict.html#Status">Status:</a></th><td>Core</td></tr> +<tr><th><a href="directive-dict.html#Module">Module:</a></th><td>core</td></tr> +<tr><th><a href="directive-dict.html#Compatibility">Compatibility:</a></th><td>Moved into the core in Apache 2.0</td></tr> +</table> + <p>When placed into an <code>.htaccess</code> file or a + <code class="directive"><a href="#directory"><Directory></a></code> or + <code class="directive"><a href="#location"><Location></a></code> + section, this directive forces all matching files to be parsed + through the <a href="../handler.html">handler</a> given by + <var>handler-name</var>. For example, if you had a directory you + wanted to be parsed entirely as imagemap rule files, regardless + of extension, you might put the following into an + <code>.htaccess</code> file in that directory:</p> + + <div class="example"><p><code> + SetHandler imap-file + </code></p></div> + + <p>Another example: if you wanted to have the server display a + status report whenever a URL of + <code>http://servername/status</code> was called, you might put + the following into <code>httpd.conf</code>:</p> + + <div class="example"><p><code> + <Location /status><br /> + <span class="indent"> + SetHandler server-status<br /> + </span> + </Location> + </code></p></div> + + <p>You can override an earlier defined <code class="directive">SetHandler</code> + directive by using the value <code>None</code>.</p> + +<h3>See also</h3> +<ul> +<li><code class="directive"><a href="../mod/mod_mime.html#addhandler">AddHandler</a></code></li> +</ul> +</div> +<div class="top"><a href="#page-header"><img alt="top" src="../images/up.gif" /></a></div> +<div class="directive-section"><h2><a name="SetInputFilter" id="SetInputFilter">SetInputFilter</a> <a name="setinputfilter" id="setinputfilter">Directive</a></h2> +<table class="directive"> +<tr><th><a href="directive-dict.html#Description">Description:</a></th><td>Sets the filters that will process client requests and POST +input</td></tr> +<tr><th><a href="directive-dict.html#Syntax">Syntax:</a></th><td><code>SetInputFilter <var>filter</var>[;<var>filter</var>...]</code></td></tr> +<tr><th><a href="directive-dict.html#Context">Context:</a></th><td>server config, virtual host, directory, .htaccess</td></tr> +<tr><th><a href="directive-dict.html#Override">Override:</a></th><td>FileInfo</td></tr> +<tr><th><a href="directive-dict.html#Status">Status:</a></th><td>Core</td></tr> +<tr><th><a href="directive-dict.html#Module">Module:</a></th><td>core</td></tr> +</table> + <p>The <code class="directive">SetInputFilter</code> directive sets the + filter or filters which will process client requests and POST + input when they are received by the server. This is in addition to + any filters defined elsewhere, including the + <code class="directive"><a href="../mod/mod_mime.html#addinputfilter">AddInputFilter</a></code> + directive.</p> + + <p>If more than one filter is specified, they must be separated + by semicolons in the order in which they should process the + content.</p> + +<h3>See also</h3> +<ul> +<li><a href="../filter.html">Filters</a> documentation</li> +</ul> +</div> +<div class="top"><a href="#page-header"><img alt="top" src="../images/up.gif" /></a></div> +<div class="directive-section"><h2><a name="SetOutputFilter" id="SetOutputFilter">SetOutputFilter</a> <a name="setoutputfilter" id="setoutputfilter">Directive</a></h2> +<table class="directive"> +<tr><th><a href="directive-dict.html#Description">Description:</a></th><td>Sets the filters that will process responses from the +server</td></tr> +<tr><th><a href="directive-dict.html#Syntax">Syntax:</a></th><td><code>SetOutputFilter <var>filter</var>[;<var>filter</var>...]</code></td></tr> +<tr><th><a href="directive-dict.html#Context">Context:</a></th><td>server config, virtual host, directory, .htaccess</td></tr> +<tr><th><a href="directive-dict.html#Override">Override:</a></th><td>FileInfo</td></tr> +<tr><th><a href="directive-dict.html#Status">Status:</a></th><td>Core</td></tr> +<tr><th><a href="directive-dict.html#Module">Module:</a></th><td>core</td></tr> +</table> + <p>The <code class="directive">SetOutputFilter</code> directive sets the filters + which will process responses from the server before they are + sent to the client. This is in addition to any filters defined + elsewhere, including the + <code class="directive"><a href="../mod/mod_mime.html#addoutputfilter">AddOutputFilter</a></code> + directive.</p> + + <p>For example, the following configuration will process all files + in the <code>/www/data/</code> directory for server-side + includes.</p> + + <div class="example"><p><code> + <Directory /www/data/><br /> + <span class="indent"> + SetOutputFilter INCLUDES<br /> + </span> + </Directory> + </code></p></div> + + <p>If more than one filter is specified, they must be separated + by semicolons in the order in which they should process the + content.</p> + +<h3>See also</h3> +<ul> +<li><a href="../filter.html">Filters</a> documentation</li> +</ul> +</div> +<div class="top"><a href="#page-header"><img alt="top" src="../images/up.gif" /></a></div> +<div class="directive-section"><h2><a name="TimeOut" id="TimeOut">TimeOut</a> <a name="timeout" id="timeout">Directive</a></h2> +<table class="directive"> +<tr><th><a href="directive-dict.html#Description">Description:</a></th><td>Amount of time the server will wait for +certain events before failing a request</td></tr> +<tr><th><a href="directive-dict.html#Syntax">Syntax:</a></th><td><code>TimeOut <var>seconds</var></code></td></tr> +<tr><th><a href="directive-dict.html#Default">Default:</a></th><td><code>TimeOut 300</code></td></tr> +<tr><th><a href="directive-dict.html#Context">Context:</a></th><td>server config, virtual host</td></tr> +<tr><th><a href="directive-dict.html#Status">Status:</a></th><td>Core</td></tr> +<tr><th><a href="directive-dict.html#Module">Module:</a></th><td>core</td></tr> +</table> + <p>The <code class="directive">TimeOut</code> directive currently defines + the amount of time Apache will wait for three things:</p> + + <ol> + <li>The total amount of time it takes to receive a GET + request.</li> + + <li>The amount of time between receipt of TCP packets on a + POST or PUT request.</li> + + <li>The amount of time between ACKs on transmissions of TCP + packets in responses.</li> + </ol> + + <p>We plan on making these separately configurable at some point + down the road. The timer used to default to 1200 before 1.2, + but has been lowered to 300 which is still far more than + necessary in most situations. It is not set any lower by + default because there may still be odd places in the code where + the timer is not reset when a packet is sent. </p> + +</div> +<div class="top"><a href="#page-header"><img alt="top" src="../images/up.gif" /></a></div> +<div class="directive-section"><h2><a name="TraceEnable" id="TraceEnable">TraceEnable</a> <a name="traceenable" id="traceenable">Directive</a></h2> +<table class="directive"> +<tr><th><a href="directive-dict.html#Description">Description:</a></th><td>Determines the behaviour on <code>TRACE</code> +requests</td></tr> +<tr><th><a href="directive-dict.html#Syntax">Syntax:</a></th><td><code>TraceEnable <var>[on|off|extended]</var></code></td></tr> +<tr><th><a href="directive-dict.html#Default">Default:</a></th><td><code>TraceEnable on</code></td></tr> +<tr><th><a href="directive-dict.html#Context">Context:</a></th><td>server config</td></tr> +<tr><th><a href="directive-dict.html#Status">Status:</a></th><td>Core</td></tr> +<tr><th><a href="directive-dict.html#Module">Module:</a></th><td>core</td></tr> +<tr><th><a href="directive-dict.html#Compatibility">Compatibility:</a></th><td>Available in Apache 1.3.34, 2.0.55 and later</td></tr> +</table> + <p>This directive overrides the behavior of <code>TRACE</code> for both + the core server and <code class="module"><a href="../mod/mod_proxy.html">mod_proxy</a></code>. The default + <code>TraceEnable on</code> permits <code>TRACE</code> requests per + RFC 2616, which disallows any request body to accompany the request. + <code>TraceEnable off</code> causes the core server and + <code class="module"><a href="../mod/mod_proxy.html">mod_proxy</a></code> to return a <code>405</code> (Method not + allowed) error to the client.</p> + + <p>Finally, for testing and diagnostic purposes only, request + bodies may be allowed using the non-compliant <code>TraceEnable + extended</code> directive. The core (as an origin server) will + restrict the request body to 64k (plus 8k for chunk headers if + <code>Transfer-Encoding: chunked</code> is used). The core will + reflect the full headers and all chunk headers with the response + body. As a proxy server, the request body is not restricted to 64k.</p> + +</div> +<div class="top"><a href="#page-header"><img alt="top" src="../images/up.gif" /></a></div> +<div class="directive-section"><h2><a name="UseCanonicalName" id="UseCanonicalName">UseCanonicalName</a> <a name="usecanonicalname" id="usecanonicalname">Directive</a></h2> +<table class="directive"> +<tr><th><a href="directive-dict.html#Description">Description:</a></th><td>Configures how the server determines its own name and +port</td></tr> +<tr><th><a href="directive-dict.html#Syntax">Syntax:</a></th><td><code>UseCanonicalName On|Off|DNS</code></td></tr> +<tr><th><a href="directive-dict.html#Default">Default:</a></th><td><code>UseCanonicalName On</code></td></tr> +<tr><th><a href="directive-dict.html#Context">Context:</a></th><td>server config, virtual host, directory</td></tr> +<tr><th><a href="directive-dict.html#Status">Status:</a></th><td>Core</td></tr> +<tr><th><a href="directive-dict.html#Module">Module:</a></th><td>core</td></tr> +</table> + <p>In many situations Apache must construct a <em>self-referential</em> + URL -- that is, a URL that refers back to the same server. With + <code>UseCanonicalName On</code> Apache will use the hostname and port + specified in the <code class="directive"><a href="#servername">ServerName</a></code> + directive to construct the canonical name for the server. This name + is used in all self-referential URLs, and for the values of + <code>SERVER_NAME</code> and <code>SERVER_PORT</code> in CGIs.</p> + + <p>With <code>UseCanonicalName Off</code> Apache will form + self-referential URLs using the hostname and port supplied by + the client if any are supplied (otherwise it will use the + canonical name, as defined above). These values are the same + that are used to implement <a href="../vhosts/name-based.html">name based virtual hosts</a>, + and are available with the same clients. The CGI variables + <code>SERVER_NAME</code> and <code>SERVER_PORT</code> will be + constructed from the client supplied values as well.</p> + + <p>An example where this may be useful is on an intranet server + where you have users connecting to the machine using short + names such as <code>www</code>. You'll notice that if the users + type a shortname, and a URL which is a directory, such as + <code>http://www/splat</code>, <em>without the trailing + slash</em> then Apache will redirect them to + <code>http://www.domain.com/splat/</code>. If you have + authentication enabled, this will cause the user to have to + authenticate twice (once for <code>www</code> and once again + for <code>www.domain.com</code> -- see <a href="http://httpd.apache.org/docs/misc/FAQ.html#prompted-twice">the + FAQ on this subject for more information</a>). But if + <code class="directive">UseCanonicalName</code> is set <code>Off</code>, then + Apache will redirect to <code>http://www/splat/</code>.</p> + + <p>There is a third option, <code>UseCanonicalName DNS</code>, + which is intended for use with mass IP-based virtual hosting to + support ancient clients that do not provide a + <code>Host:</code> header. With this option Apache does a + reverse DNS lookup on the server IP address that the client + connected to in order to work out self-referential URLs.</p> + + <div class="warning"><h3>Warning</h3> + <p>If CGIs make assumptions about the values of <code>SERVER_NAME</code> + they may be broken by this option. The client is essentially free + to give whatever value they want as a hostname. But if the CGI is + only using <code>SERVER_NAME</code> to construct self-referential URLs + then it should be just fine.</p> + </div> + +<h3>See also</h3> +<ul> +<li><code class="directive"><a href="#servername">ServerName</a></code></li> +<li><code class="directive"><a href="../mod/mpm_common.html#listen">Listen</a></code></li> +</ul> +</div> +<div class="top"><a href="#page-header"><img alt="top" src="../images/up.gif" /></a></div> +<div class="directive-section"><h2><a name="VirtualHost" id="VirtualHost"><VirtualHost></a> <a name="virtualhost" id="virtualhost">Directive</a></h2> +<table class="directive"> +<tr><th><a href="directive-dict.html#Description">Description:</a></th><td>Contains directives that apply only to a specific +hostname or IP address</td></tr> +<tr><th><a href="directive-dict.html#Syntax">Syntax:</a></th><td><code><VirtualHost + <var>addr</var>[:<var>port</var>] [<var>addr</var>[:<var>port</var>]] + ...> ... </VirtualHost></code></td></tr> +<tr><th><a href="directive-dict.html#Context">Context:</a></th><td>server config</td></tr> +<tr><th><a href="directive-dict.html#Status">Status:</a></th><td>Core</td></tr> +<tr><th><a href="directive-dict.html#Module">Module:</a></th><td>core</td></tr> +</table> + <p><code class="directive"><VirtualHost></code> and + <code></VirtualHost></code> are used to enclose a group of + directives that will apply only to a particular virtual host. Any + directive that is allowed in a virtual host context may be + used. When the server receives a request for a document on a + particular virtual host, it uses the configuration directives + enclosed in the <code class="directive"><VirtualHost></code> + section. <var>Addr</var> can be:</p> + + <ul> + <li>The IP address of the virtual host;</li> + + <li>A fully qualified domain name for the IP address of the + virtual host;</li> + + <li>The character <code>*</code>, which is used only in combination with + <code>NameVirtualHost *</code> to match all IP addresses; or</li> + + <li>The string <code>_default_</code>, which is used only + with IP virtual hosting to catch unmatched IP addresses.</li> + </ul> + + <div class="example"><h3>Example</h3><p><code> + <VirtualHost 10.1.2.3><br /> + <span class="indent"> + ServerAdmin webmaster@host.foo.com<br /> + DocumentRoot /www/docs/host.foo.com<br /> + ServerName host.foo.com<br /> + ErrorLog logs/host.foo.com-error_log<br /> + TransferLog logs/host.foo.com-access_log<br /> + </span> + </VirtualHost> + </code></p></div> + + + <p>IPv6 addresses must be specified in square brackets because + the optional port number could not be determined otherwise. An + IPv6 example is shown below:</p> + + <div class="example"><p><code> + <VirtualHost [2001:db8::a00:20ff:fea7:ccea]><br /> + <span class="indent"> + ServerAdmin webmaster@host.example.com<br /> + DocumentRoot /www/docs/host.example.com<br /> + ServerName host.example.com<br /> + ErrorLog logs/host.example.com-error_log<br /> + TransferLog logs/host.example.com-access_log<br /> + </span> + </VirtualHost> + </code></p></div> + + <p>Each Virtual Host must correspond to a different IP address, + different port number or a different host name for the server, + in the former case the server machine must be configured to + accept IP packets for multiple addresses. (If the machine does + not have multiple network interfaces, then this can be + accomplished with the <code>ifconfig alias</code> command -- if + your OS supports it).</p> + + <div class="note"><h3>Note</h3> + <p>The use of <code class="directive"><VirtualHost></code> does + <strong>not</strong> affect what addresses Apache listens on. You + may need to ensure that Apache is listening on the correct addresses + using <code class="directive"><a href="../mod/mpm_common.html#listen">Listen</a></code>.</p> + </div> + + <p>When using IP-based virtual hosting, the special name + <code>_default_</code> can be specified in + which case this virtual host will match any IP address that is + not explicitly listed in another virtual host. In the absence + of any <code>_default_</code> virtual host the "main" server config, + consisting of all those definitions outside any VirtualHost + section, is used when no IP-match occurs. (But note that any IP + address that matches a <code class="directive"><a href="#namevirtualhost">NameVirtualHost</a></code> directive will use neither + the "main" server config nor the <code>_default_</code> virtual host. + See the <a href="../vhosts/name-based.html">name-based virtual hosting</a> + documentation for further details.)</p> + + <p>You can specify a <code>:port</code> to change the port that is + matched. If unspecified then it defaults to the same port as the + most recent <code class="directive"><a href="../mod/mpm_common.html#listen">Listen</a></code> + statement of the main server. You may also specify <code>:*</code> + to match all ports on that address. (This is recommended when used + with <code>_default_</code>.)</p> + + <div class="warning"><h3>Security</h3> + <p>See the <a href="../misc/security_tips.html">security tips</a> + document for details on why your security could be compromised if the + directory where log files are stored is writable by anyone other + than the user that starts the server.</p> + </div> + +<h3>See also</h3> +<ul> +<li><a href="../vhosts/">Apache Virtual Host documentation</a></li> +<li><a href="../dns-caveats.html">Issues Regarding DNS and + Apache</a></li> +<li><a href="../bind.html">Setting + which addresses and ports Apache uses</a></li> +<li><a href="../sections.html">How <Directory>, <Location> + and <Files> sections work</a> for an explanation of how these + different sections are combined when a request is received</li> +</ul> +</div> +</div> +<div class="bottomlang"> +<p><span>Available Languages: </span><a href="../de/mod/core.html" hreflang="de" rel="alternate" title="Deutsch"> de </a> | +<a href="../en/mod/core.html" title="English"> en </a> | +<a href="../es/mod/core.html" hreflang="es" rel="alternate" title="Español"> es </a> | +<a href="../ja/mod/core.html" hreflang="ja" rel="alternate" title="Japanese"> ja </a> | +<a href="../tr/mod/core.html" hreflang="tr" rel="alternate" title="Türkçe"> tr </a></p> +</div><div id="footer"> +<p class="apache">Copyright 2009 The Apache Software Foundation.<br />Licensed under the <a href="http://www.apache.org/licenses/LICENSE-2.0">Apache License, Version 2.0</a>.</p> +<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></div> +</body></html>
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