1 <?xml version="1.0" encoding="ISO-8859-1"?>
2 <!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Strict//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-strict.dtd">
3 <html xmlns="http://www.w3.org/1999/xhtml" lang="en" xml:lang="en"><head>
4 <meta content="text/html; charset=ISO-8859-1" http-equiv="Content-Type" />
6 XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX
7 This file is generated from xml source: DO NOT EDIT
8 XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX
10 <title>core - Apache HTTP Server Version 2.5</title>
11 <link href="../style/css/manual.css" rel="stylesheet" media="all" type="text/css" title="Main stylesheet" />
12 <link href="../style/css/manual-loose-100pc.css" rel="alternate stylesheet" media="all" type="text/css" title="No Sidebar - Default font size" />
13 <link href="../style/css/manual-print.css" rel="stylesheet" media="print" type="text/css" /><link rel="stylesheet" type="text/css" href="../style/css/prettify.css" />
14 <script src="../style/scripts/prettify.min.js" type="text/javascript">
17 <link href="../images/favicon.ico" rel="shortcut icon" /></head>
19 <div id="page-header">
20 <p class="menu"><a href="../mod/">Modules</a> | <a href="../mod/quickreference.html">Directives</a> | <a href="http://wiki.apache.org/httpd/FAQ">FAQ</a> | <a href="../glossary.html">Glossary</a> | <a href="../sitemap.html">Sitemap</a></p>
21 <p class="apache">Apache HTTP Server Version 2.5</p>
22 <img alt="" src="../images/feather.gif" /></div>
23 <div class="up"><a href="./"><img title="<-" alt="<-" src="../images/left.gif" /></a></div>
25 <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 2.5</a> > <a href="./">Modules</a></div>
26 <div id="page-content">
27 <div id="preamble"><h1>Apache Core Features</h1>
29 <p><span>Available Languages: </span><a href="../de/mod/core.html" hreflang="de" rel="alternate" title="Deutsch"> de </a> |
30 <a href="../en/mod/core.html" title="English"> en </a> |
31 <a href="../es/mod/core.html" hreflang="es" rel="alternate" title="Español"> es </a> |
32 <a href="../fr/mod/core.html" hreflang="fr" rel="alternate" title="Français"> fr </a> |
33 <a href="../ja/mod/core.html" hreflang="ja" rel="alternate" title="Japanese"> ja </a> |
34 <a href="../tr/mod/core.html" hreflang="tr" rel="alternate" title="Türkçe"> tr </a></p>
36 <table class="module"><tr><th><a href="module-dict.html#Description">Description:</a></th><td>Core Apache HTTP Server features that are always
38 <tr><th><a href="module-dict.html#Status">Status:</a></th><td>Core</td></tr></table>
40 <div id="quickview"><h3 class="directives">Directives</h3>
42 <li><img alt="" src="../images/down.gif" /> <a href="#acceptfilter">AcceptFilter</a></li>
43 <li><img alt="" src="../images/down.gif" /> <a href="#acceptpathinfo">AcceptPathInfo</a></li>
44 <li><img alt="" src="../images/down.gif" /> <a href="#accessfilename">AccessFileName</a></li>
45 <li><img alt="" src="../images/down.gif" /> <a href="#adddefaultcharset">AddDefaultCharset</a></li>
46 <li><img alt="" src="../images/down.gif" /> <a href="#allowencodedslashes">AllowEncodedSlashes</a></li>
47 <li><img alt="" src="../images/down.gif" /> <a href="#allowoverride">AllowOverride</a></li>
48 <li><img alt="" src="../images/down.gif" /> <a href="#allowoverridelist">AllowOverrideList</a></li>
49 <li><img alt="" src="../images/down.gif" /> <a href="#cgimapextension">CGIMapExtension</a></li>
50 <li><img alt="" src="../images/down.gif" /> <a href="#cgipassauth">CGIPassAuth</a></li>
51 <li><img alt="" src="../images/down.gif" /> <a href="#contentdigest">ContentDigest</a></li>
52 <li><img alt="" src="../images/down.gif" /> <a href="#defaultruntimedir">DefaultRuntimeDir</a></li>
53 <li><img alt="" src="../images/down.gif" /> <a href="#defaulttype">DefaultType</a></li>
54 <li><img alt="" src="../images/down.gif" /> <a href="#define">Define</a></li>
55 <li><img alt="" src="../images/down.gif" /> <a href="#directory"><Directory></a></li>
56 <li><img alt="" src="../images/down.gif" /> <a href="#directorymatch"><DirectoryMatch></a></li>
57 <li><img alt="" src="../images/down.gif" /> <a href="#documentroot">DocumentRoot</a></li>
58 <li><img alt="" src="../images/down.gif" /> <a href="#else"><Else></a></li>
59 <li><img alt="" src="../images/down.gif" /> <a href="#elseif"><ElseIf></a></li>
60 <li><img alt="" src="../images/down.gif" /> <a href="#enablemmap">EnableMMAP</a></li>
61 <li><img alt="" src="../images/down.gif" /> <a href="#enablesendfile">EnableSendfile</a></li>
62 <li><img alt="" src="../images/down.gif" /> <a href="#error">Error</a></li>
63 <li><img alt="" src="../images/down.gif" /> <a href="#errordocument">ErrorDocument</a></li>
64 <li><img alt="" src="../images/down.gif" /> <a href="#errorlog">ErrorLog</a></li>
65 <li><img alt="" src="../images/down.gif" /> <a href="#errorlogformat">ErrorLogFormat</a></li>
66 <li><img alt="" src="../images/down.gif" /> <a href="#extendedstatus">ExtendedStatus</a></li>
67 <li><img alt="" src="../images/down.gif" /> <a href="#fileetag">FileETag</a></li>
68 <li><img alt="" src="../images/down.gif" /> <a href="#files"><Files></a></li>
69 <li><img alt="" src="../images/down.gif" /> <a href="#filesmatch"><FilesMatch></a></li>
70 <li><img alt="" src="../images/down.gif" /> <a href="#forcetype">ForceType</a></li>
71 <li><img alt="" src="../images/down.gif" /> <a href="#gprofdir">GprofDir</a></li>
72 <li><img alt="" src="../images/down.gif" /> <a href="#hostnamelookups">HostnameLookups</a></li>
73 <li><img alt="" src="../images/down.gif" /> <a href="#if"><If></a></li>
74 <li><img alt="" src="../images/down.gif" /> <a href="#ifdefine"><IfDefine></a></li>
75 <li><img alt="" src="../images/down.gif" /> <a href="#ifmodule"><IfModule></a></li>
76 <li><img alt="" src="../images/down.gif" /> <a href="#include">Include</a></li>
77 <li><img alt="" src="../images/down.gif" /> <a href="#includeoptional">IncludeOptional</a></li>
78 <li><img alt="" src="../images/down.gif" /> <a href="#keepalive">KeepAlive</a></li>
79 <li><img alt="" src="../images/down.gif" /> <a href="#keepalivetimeout">KeepAliveTimeout</a></li>
80 <li><img alt="" src="../images/down.gif" /> <a href="#limit"><Limit></a></li>
81 <li><img alt="" src="../images/down.gif" /> <a href="#limitexcept"><LimitExcept></a></li>
82 <li><img alt="" src="../images/down.gif" /> <a href="#limitinternalrecursion">LimitInternalRecursion</a></li>
83 <li><img alt="" src="../images/down.gif" /> <a href="#limitrequestbody">LimitRequestBody</a></li>
84 <li><img alt="" src="../images/down.gif" /> <a href="#limitrequestfields">LimitRequestFields</a></li>
85 <li><img alt="" src="../images/down.gif" /> <a href="#limitrequestfieldsize">LimitRequestFieldSize</a></li>
86 <li><img alt="" src="../images/down.gif" /> <a href="#limitrequestline">LimitRequestLine</a></li>
87 <li><img alt="" src="../images/down.gif" /> <a href="#limitxmlrequestbody">LimitXMLRequestBody</a></li>
88 <li><img alt="" src="../images/down.gif" /> <a href="#location"><Location></a></li>
89 <li><img alt="" src="../images/down.gif" /> <a href="#locationmatch"><LocationMatch></a></li>
90 <li><img alt="" src="../images/down.gif" /> <a href="#loglevel">LogLevel</a></li>
91 <li><img alt="" src="../images/down.gif" /> <a href="#logleveloverride">LogLevelOverride</a></li>
92 <li><img alt="" src="../images/down.gif" /> <a href="#maxkeepaliverequests">MaxKeepAliveRequests</a></li>
93 <li><img alt="" src="../images/down.gif" /> <a href="#maxrangeoverlaps">MaxRangeOverlaps</a></li>
94 <li><img alt="" src="../images/down.gif" /> <a href="#maxrangereversals">MaxRangeReversals</a></li>
95 <li><img alt="" src="../images/down.gif" /> <a href="#maxranges">MaxRanges</a></li>
96 <li><img alt="" src="../images/down.gif" /> <a href="#mergetrailers">MergeTrailers</a></li>
97 <li><img alt="" src="../images/down.gif" /> <a href="#mutex">Mutex</a></li>
98 <li><img alt="" src="../images/down.gif" /> <a href="#namevirtualhost">NameVirtualHost</a></li>
99 <li><img alt="" src="../images/down.gif" /> <a href="#options">Options</a></li>
100 <li><img alt="" src="../images/down.gif" /> <a href="#protocol">Protocol</a></li>
101 <li><img alt="" src="../images/down.gif" /> <a href="#registerhttpmethod">RegisterHttpMethod</a></li>
102 <li><img alt="" src="../images/down.gif" /> <a href="#rlimitcpu">RLimitCPU</a></li>
103 <li><img alt="" src="../images/down.gif" /> <a href="#rlimitmem">RLimitMEM</a></li>
104 <li><img alt="" src="../images/down.gif" /> <a href="#rlimitnproc">RLimitNPROC</a></li>
105 <li><img alt="" src="../images/down.gif" /> <a href="#scriptinterpretersource">ScriptInterpreterSource</a></li>
106 <li><img alt="" src="../images/down.gif" /> <a href="#seerequesttail">SeeRequestTail</a></li>
107 <li><img alt="" src="../images/down.gif" /> <a href="#serveradmin">ServerAdmin</a></li>
108 <li><img alt="" src="../images/down.gif" /> <a href="#serveralias">ServerAlias</a></li>
109 <li><img alt="" src="../images/down.gif" /> <a href="#servername">ServerName</a></li>
110 <li><img alt="" src="../images/down.gif" /> <a href="#serverpath">ServerPath</a></li>
111 <li><img alt="" src="../images/down.gif" /> <a href="#serverroot">ServerRoot</a></li>
112 <li><img alt="" src="../images/down.gif" /> <a href="#serversignature">ServerSignature</a></li>
113 <li><img alt="" src="../images/down.gif" /> <a href="#servertokens">ServerTokens</a></li>
114 <li><img alt="" src="../images/down.gif" /> <a href="#sethandler">SetHandler</a></li>
115 <li><img alt="" src="../images/down.gif" /> <a href="#setinputfilter">SetInputFilter</a></li>
116 <li><img alt="" src="../images/down.gif" /> <a href="#setoutputfilter">SetOutputFilter</a></li>
117 <li><img alt="" src="../images/down.gif" /> <a href="#timeout">TimeOut</a></li>
118 <li><img alt="" src="../images/down.gif" /> <a href="#traceenable">TraceEnable</a></li>
119 <li><img alt="" src="../images/down.gif" /> <a href="#undefine">UnDefine</a></li>
120 <li><img alt="" src="../images/down.gif" /> <a href="#usecanonicalname">UseCanonicalName</a></li>
121 <li><img alt="" src="../images/down.gif" /> <a href="#usecanonicalphysicalport">UseCanonicalPhysicalPort</a></li>
122 <li><img alt="" src="../images/down.gif" /> <a href="#virtualhost"><VirtualHost></a></li>
123 <li><img alt="" src="../images/down.gif" /> <a href="#warning">Warning</a></li>
125 <ul class="seealso"><li><a href="#comments_section">Comments</a></li></ul></div>
127 <div class="top"><a href="#page-header"><img alt="top" src="../images/up.gif" /></a></div>
128 <div class="directive-section"><h2><a name="AcceptFilter" id="AcceptFilter">AcceptFilter</a> <a name="acceptfilter" id="acceptfilter">Directive</a></h2>
129 <table class="directive">
130 <tr><th><a href="directive-dict.html#Description">Description:</a></th><td>Configures optimizations for a Protocol's Listener Sockets</td></tr>
131 <tr><th><a href="directive-dict.html#Syntax">Syntax:</a></th><td><code>AcceptFilter <var>protocol</var> <var>accept_filter</var></code></td></tr>
132 <tr><th><a href="directive-dict.html#Context">Context:</a></th><td>server config</td></tr>
133 <tr><th><a href="directive-dict.html#Status">Status:</a></th><td>Core</td></tr>
134 <tr><th><a href="directive-dict.html#Module">Module:</a></th><td>core</td></tr>
136 <p>This directive enables operating system specific optimizations for a
137 listening socket by the <code class="directive">Protocol</code> type.
138 The basic premise is for the kernel to not send a socket to the server
139 process until either data is received or an entire HTTP Request is buffered.
140 Only <a href="http://www.freebsd.org/cgi/man.cgi?query=accept_filter&sektion=9">
141 FreeBSD's Accept Filters</a>, Linux's more primitive
142 <code>TCP_DEFER_ACCEPT</code>, and Windows' optimized AcceptEx()
143 are currently supported.</p>
145 <p>Using <code>none</code> for an argument will disable any accept filters
146 for that protocol. This is useful for protocols that require a server
147 send data first, such as <code>ftp:</code> or <code>nntp</code>:</p>
148 <pre class="prettyprint lang-config">AcceptFilter nntp none</pre>
151 <p>The default protocol names are <code>https</code> for port 443
152 and <code>http</code> for all other ports. To specify that another
153 protocol is being used with a listening port, add the <var>protocol</var>
154 argument to the <code class="directive"><a href="../mod/mpm_common.html#listen">Listen</a></code>
157 <p>The default values on FreeBSD are:</p>
158 <pre class="prettyprint lang-config">AcceptFilter http httpready
159 AcceptFilter https dataready</pre>
162 <p>The <code>httpready</code> accept filter buffers entire HTTP requests at
163 the kernel level. Once an entire request is received, the kernel then
164 sends it to the server. See the
165 <a href="http://www.freebsd.org/cgi/man.cgi?query=accf_http&sektion=9">
166 accf_http(9)</a> man page for more details. Since HTTPS requests are
167 encrypted, only the <a href="http://www.freebsd.org/cgi/man.cgi?query=accf_data&sektion=9">
168 accf_data(9)</a> filter is used.</p>
170 <p>The default values on Linux are:</p>
171 <pre class="prettyprint lang-config">AcceptFilter http data
172 AcceptFilter https data</pre>
175 <p>Linux's <code>TCP_DEFER_ACCEPT</code> does not support buffering http
176 requests. Any value besides <code>none</code> will enable
177 <code>TCP_DEFER_ACCEPT</code> on that listener. For more details
179 <a href="http://homepages.cwi.nl/~aeb/linux/man2html/man7/tcp.7.html">
180 tcp(7)</a> man page.</p>
182 <p>The default values on Windows are:</p>
183 <pre class="prettyprint lang-config">AcceptFilter http data
184 AcceptFilter https data</pre>
187 <p>Window's mpm_winnt interprets the AcceptFilter to toggle the AcceptEx()
188 API, and does not support http protocol buffering. There are two values
189 which utilize the Windows AcceptEx() API and will recycle network
190 sockets between connections. <code>data</code> waits until data has
191 been transmitted as documented above, and the initial data buffer and
192 network endpoint addresses are all retrieved from the single AcceptEx()
193 invocation. <code>connect</code> will use the AcceptEx() API, also
194 retrieve the network endpoint addresses, but like <code>none</code>
195 the <code>connect</code> option does not wait for the initial data
198 <p>On Windows, <code>none</code> uses accept() rather than AcceptEx()
199 and will not recycle sockets between connections. This is useful for
200 network adapters with broken driver support, as well as some virtual
201 network providers such as vpn drivers, or spam, virus or spyware
207 <li><code class="directive"><a href="#protocol">Protocol</a></code></li>
210 <div class="top"><a href="#page-header"><img alt="top" src="../images/up.gif" /></a></div>
211 <div class="directive-section"><h2><a name="AcceptPathInfo" id="AcceptPathInfo">AcceptPathInfo</a> <a name="acceptpathinfo" id="acceptpathinfo">Directive</a></h2>
212 <table class="directive">
213 <tr><th><a href="directive-dict.html#Description">Description:</a></th><td>Resources accept trailing pathname information</td></tr>
214 <tr><th><a href="directive-dict.html#Syntax">Syntax:</a></th><td><code>AcceptPathInfo On|Off|Default</code></td></tr>
215 <tr><th><a href="directive-dict.html#Default">Default:</a></th><td><code>AcceptPathInfo Default</code></td></tr>
216 <tr><th><a href="directive-dict.html#Context">Context:</a></th><td>server config, virtual host, directory, .htaccess</td></tr>
217 <tr><th><a href="directive-dict.html#Override">Override:</a></th><td>FileInfo</td></tr>
218 <tr><th><a href="directive-dict.html#Status">Status:</a></th><td>Core</td></tr>
219 <tr><th><a href="directive-dict.html#Module">Module:</a></th><td>core</td></tr>
222 <p>This directive controls whether requests that contain trailing
223 pathname information that follows an actual filename (or
224 non-existent file in an existing directory) will be accepted or
225 rejected. The trailing pathname information can be made
226 available to scripts in the <code>PATH_INFO</code> environment
229 <p>For example, assume the location <code>/test/</code> points to
230 a directory that contains only the single file
231 <code>here.html</code>. Then requests for
232 <code>/test/here.html/more</code> and
233 <code>/test/nothere.html/more</code> both collect
234 <code>/more</code> as <code>PATH_INFO</code>.</p>
236 <p>The three possible arguments for the
237 <code class="directive">AcceptPathInfo</code> directive are:</p>
239 <dt><code>Off</code></dt><dd>A request will only be accepted if it
240 maps to a literal path that exists. Therefore a request with
241 trailing pathname information after the true filename such as
242 <code>/test/here.html/more</code> in the above example will return
243 a 404 NOT FOUND error.</dd>
245 <dt><code>On</code></dt><dd>A request will be accepted if a
246 leading path component maps to a file that exists. The above
247 example <code>/test/here.html/more</code> will be accepted if
248 <code>/test/here.html</code> maps to a valid file.</dd>
250 <dt><code>Default</code></dt><dd>The treatment of requests with
251 trailing pathname information is determined by the <a href="../handler.html">handler</a> responsible for the request.
252 The core handler for normal files defaults to rejecting
253 <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
254 <code>PATH_INFO</code> by default.</dd>
257 <p>The primary purpose of the <code>AcceptPathInfo</code>
258 directive is to allow you to override the handler's choice of
259 accepting or rejecting <code>PATH_INFO</code>. This override is required,
260 for example, when you use a <a href="../filter.html">filter</a>, such
261 as <a href="mod_include.html">INCLUDES</a>, to generate content
262 based on <code>PATH_INFO</code>. The core handler would usually reject
263 the request, so you can use the following configuration to enable
266 <pre class="prettyprint lang-config"><Files "mypaths.shtml">
268 SetOutputFilter INCLUDES
275 <div class="top"><a href="#page-header"><img alt="top" src="../images/up.gif" /></a></div>
276 <div class="directive-section"><h2><a name="AccessFileName" id="AccessFileName">AccessFileName</a> <a name="accessfilename" id="accessfilename">Directive</a></h2>
277 <table class="directive">
278 <tr><th><a href="directive-dict.html#Description">Description:</a></th><td>Name of the distributed configuration file</td></tr>
279 <tr><th><a href="directive-dict.html#Syntax">Syntax:</a></th><td><code>AccessFileName <var>filename</var> [<var>filename</var>] ...</code></td></tr>
280 <tr><th><a href="directive-dict.html#Default">Default:</a></th><td><code>AccessFileName .htaccess</code></td></tr>
281 <tr><th><a href="directive-dict.html#Context">Context:</a></th><td>server config, virtual host</td></tr>
282 <tr><th><a href="directive-dict.html#Status">Status:</a></th><td>Core</td></tr>
283 <tr><th><a href="directive-dict.html#Module">Module:</a></th><td>core</td></tr>
285 <p>While processing a request, the server looks for
286 the first existing configuration file from this list of names in
287 every directory of the path to the document, if distributed
288 configuration files are <a href="#allowoverride">enabled for that
289 directory</a>. For example:</p>
291 <pre class="prettyprint lang-config">AccessFileName .acl</pre>
294 <p>Before returning the document
295 <code>/usr/local/web/index.html</code>, the server will read
296 <code>/.acl</code>, <code>/usr/.acl</code>,
297 <code>/usr/local/.acl</code> and <code>/usr/local/web/.acl</code>
298 for directives unless they have been disabled with:</p>
300 <pre class="prettyprint lang-config"><Directory "/">
302 </Directory></pre>
307 <li><code class="directive"><a href="#allowoverride">AllowOverride</a></code></li>
308 <li><a href="../configuring.html">Configuration Files</a></li>
309 <li><a href="../howto/htaccess.html">.htaccess Files</a></li>
312 <div class="top"><a href="#page-header"><img alt="top" src="../images/up.gif" /></a></div>
313 <div class="directive-section"><h2><a name="AddDefaultCharset" id="AddDefaultCharset">AddDefaultCharset</a> <a name="adddefaultcharset" id="adddefaultcharset">Directive</a></h2>
314 <table class="directive">
315 <tr><th><a href="directive-dict.html#Description">Description:</a></th><td>Default charset parameter to be added when a response
316 content-type is <code>text/plain</code> or <code>text/html</code></td></tr>
317 <tr><th><a href="directive-dict.html#Syntax">Syntax:</a></th><td><code>AddDefaultCharset On|Off|<var>charset</var></code></td></tr>
318 <tr><th><a href="directive-dict.html#Default">Default:</a></th><td><code>AddDefaultCharset Off</code></td></tr>
319 <tr><th><a href="directive-dict.html#Context">Context:</a></th><td>server config, virtual host, directory, .htaccess</td></tr>
320 <tr><th><a href="directive-dict.html#Override">Override:</a></th><td>FileInfo</td></tr>
321 <tr><th><a href="directive-dict.html#Status">Status:</a></th><td>Core</td></tr>
322 <tr><th><a href="directive-dict.html#Module">Module:</a></th><td>core</td></tr>
324 <p>This directive specifies a default value for the media type
325 charset parameter (the name of a character encoding) to be added
326 to a response if and only if the response's content-type is either
327 <code>text/plain</code> or <code>text/html</code>. This should override
328 any charset specified in the body of the response via a <code>META</code>
329 element, though the exact behavior is often dependent on the user's client
330 configuration. A setting of <code>AddDefaultCharset Off</code>
331 disables this functionality. <code>AddDefaultCharset On</code> enables
332 a default charset of <code>iso-8859-1</code>. Any other value is assumed
333 to be the <var>charset</var> to be used, which should be one of the
334 <a href="http://www.iana.org/assignments/character-sets">IANA registered
335 charset values</a> for use in Internet media types (MIME types).
338 <pre class="prettyprint lang-config">AddDefaultCharset utf-8</pre>
341 <p><code class="directive">AddDefaultCharset</code> should only be used when all
342 of the text resources to which it applies are known to be in that
343 character encoding and it is too inconvenient to label their charset
344 individually. One such example is to add the charset parameter
345 to resources containing generated content, such as legacy CGI
346 scripts, that might be vulnerable to cross-site scripting attacks
347 due to user-provided data being included in the output. Note, however,
348 that a better solution is to just fix (or delete) those scripts, since
349 setting a default charset does not protect users that have enabled
350 the "auto-detect character encoding" feature on their browser.</p>
354 <li><code class="directive"><a href="../mod/mod_mime.html#addcharset">AddCharset</a></code></li>
357 <div class="top"><a href="#page-header"><img alt="top" src="../images/up.gif" /></a></div>
358 <div class="directive-section"><h2><a name="AllowEncodedSlashes" id="AllowEncodedSlashes">AllowEncodedSlashes</a> <a name="allowencodedslashes" id="allowencodedslashes">Directive</a></h2>
359 <table class="directive">
360 <tr><th><a href="directive-dict.html#Description">Description:</a></th><td>Determines whether encoded path separators in URLs are allowed to
361 be passed through</td></tr>
362 <tr><th><a href="directive-dict.html#Syntax">Syntax:</a></th><td><code>AllowEncodedSlashes On|Off|NoDecode</code></td></tr>
363 <tr><th><a href="directive-dict.html#Default">Default:</a></th><td><code>AllowEncodedSlashes Off</code></td></tr>
364 <tr><th><a href="directive-dict.html#Context">Context:</a></th><td>server config, virtual host</td></tr>
365 <tr><th><a href="directive-dict.html#Status">Status:</a></th><td>Core</td></tr>
366 <tr><th><a href="directive-dict.html#Module">Module:</a></th><td>core</td></tr>
367 <tr><th><a href="directive-dict.html#Compatibility">Compatibility:</a></th><td>
368 NoDecode option available in 2.3.12 and later.</td></tr>
370 <p>The <code class="directive">AllowEncodedSlashes</code> directive allows URLs
371 which contain encoded path separators (<code>%2F</code> for <code>/</code>
372 and additionally <code>%5C</code> for <code>\</code> on accordant systems)
373 to be used in the path info.</p>
375 <p>With the default value, <code>Off</code>, such URLs are refused
376 with a 404 (Not found) error.</p>
378 <p>With the value <code>On</code>, such URLs are accepted, and encoded
379 slashes are decoded like all other encoded characters.</p>
381 <p>With the value <code>NoDecode</code>, such URLs are accepted, but
382 encoded slashes are not decoded but left in their encoded state.</p>
384 <p>Turning <code class="directive">AllowEncodedSlashes</code> <code>On</code> is
385 mostly useful when used in conjunction with <code>PATH_INFO</code>.</p>
387 <div class="note"><h3>Note</h3>
388 <p>If encoded slashes are needed in path info, use of <code>NoDecode</code> is
389 strongly recommended as a security measure. Allowing slashes
390 to be decoded could potentially allow unsafe paths.</p>
395 <li><code class="directive"><a href="#acceptpathinfo">AcceptPathInfo</a></code></li>
398 <div class="top"><a href="#page-header"><img alt="top" src="../images/up.gif" /></a></div>
399 <div class="directive-section"><h2><a name="AllowOverride" id="AllowOverride">AllowOverride</a> <a name="allowoverride" id="allowoverride">Directive</a></h2>
400 <table class="directive">
401 <tr><th><a href="directive-dict.html#Description">Description:</a></th><td>Types of directives that are allowed in
402 <code>.htaccess</code> files</td></tr>
403 <tr><th><a href="directive-dict.html#Syntax">Syntax:</a></th><td><code>AllowOverride All|None|<var>directive-type</var>
404 [<var>directive-type</var>] ...</code></td></tr>
405 <tr><th><a href="directive-dict.html#Default">Default:</a></th><td><code>AllowOverride None (2.3.9 and later), AllowOverride All (2.3.8 and earlier)</code></td></tr>
406 <tr><th><a href="directive-dict.html#Context">Context:</a></th><td>directory</td></tr>
407 <tr><th><a href="directive-dict.html#Status">Status:</a></th><td>Core</td></tr>
408 <tr><th><a href="directive-dict.html#Module">Module:</a></th><td>core</td></tr>
410 <p>When the server finds an <code>.htaccess</code> file (as
411 specified by <code class="directive"><a href="#accessfilename">AccessFileName</a></code>),
412 it needs to know which directives declared in that file can override
413 earlier configuration directives.</p>
415 <div class="note"><h3>Only available in <Directory> sections</h3>
416 <code class="directive">AllowOverride</code> is valid only in
417 <code class="directive"><a href="#directory"><Directory></a></code>
418 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
419 <code class="directive"><a href="#files"><Files></a></code> sections.
422 <p>When this directive is set to <code>None</code> and <code class="directive"><a href="#allowoverridelist">AllowOverrideList</a></code> is set to
423 <code>None</code>, <a href="#accessfilename">.htaccess</a> files are
424 completely ignored. In this case, the server will not even attempt
425 to read <code>.htaccess</code> files in the filesystem.</p>
427 <p>When this directive is set to <code>All</code>, then any
428 directive which has the .htaccess <a href="directive-dict.html#Context">Context</a> is allowed in
429 <code>.htaccess</code> files.</p>
431 <p>The <var>directive-type</var> can be one of the following
432 groupings of directives.</p>
439 Allow use of the authorization directives (<code class="directive"><a href="../mod/mod_authz_dbm.html#authdbmgroupfile">AuthDBMGroupFile</a></code>,
440 <code class="directive"><a href="../mod/mod_authn_dbm.html#authdbmuserfile">AuthDBMUserFile</a></code>,
441 <code class="directive"><a href="../mod/mod_authz_groupfile.html#authgroupfile">AuthGroupFile</a></code>,
442 <code class="directive"><a href="../mod/mod_authn_core.html#authname">AuthName</a></code>,
443 <code class="directive"><a href="../mod/mod_authn_core.html#authtype">AuthType</a></code>, <code class="directive"><a href="../mod/mod_authn_file.html#authuserfile">AuthUserFile</a></code>, <code class="directive"><a href="../mod/mod_authz_core.html#require">Require</a></code>, <em>etc.</em>).</dd>
448 Allow use of the directives controlling document types
449 (<code class="directive"><a href="#errordocument">ErrorDocument</a></code>,
450 <code class="directive"><a href="#forcetype">ForceType</a></code>,
451 <code class="directive"><a href="../mod/mod_negotiation.html#languagepriority">LanguagePriority</a></code>,
452 <code class="directive"><a href="#sethandler">SetHandler</a></code>,
453 <code class="directive"><a href="#setinputfilter">SetInputFilter</a></code>,
454 <code class="directive"><a href="#setoutputfilter">SetOutputFilter</a></code>, and
455 <code class="module"><a href="../mod/mod_mime.html">mod_mime</a></code> Add* and Remove* directives),
456 document meta data (<code class="directive"><a href="../mod/mod_headers.html#header">Header</a></code>, <code class="directive"><a href="../mod/mod_headers.html#requestheader">RequestHeader</a></code>, <code class="directive"><a href="../mod/mod_setenvif.html#setenvif">SetEnvIf</a></code>, <code class="directive"><a href="../mod/mod_setenvif.html#setenvifnocase">SetEnvIfNoCase</a></code>, <code class="directive"><a href="../mod/mod_setenvif.html#browsermatch">BrowserMatch</a></code>, <code class="directive"><a href="../mod/mod_usertrack.html#cookieexpires">CookieExpires</a></code>, <code class="directive"><a href="../mod/mod_usertrack.html#cookiedomain">CookieDomain</a></code>, <code class="directive"><a href="../mod/mod_usertrack.html#cookiestyle">CookieStyle</a></code>, <code class="directive"><a href="../mod/mod_usertrack.html#cookietracking">CookieTracking</a></code>, <code class="directive"><a href="../mod/mod_usertrack.html#cookiename">CookieName</a></code>),
457 <code class="module"><a href="../mod/mod_rewrite.html">mod_rewrite</a></code> directives (<code class="directive"><a href="../mod/mod_rewrite.html#rewriteengine">RewriteEngine</a></code>, <code class="directive"><a href="../mod/mod_rewrite.html#rewriteoptions">RewriteOptions</a></code>, <code class="directive"><a href="../mod/mod_rewrite.html#rewritebase">RewriteBase</a></code>, <code class="directive"><a href="../mod/mod_rewrite.html#rewritecond">RewriteCond</a></code>, <code class="directive"><a href="../mod/mod_rewrite.html#rewriterule">RewriteRule</a></code>),
458 <code class="module"><a href="../mod/mod_alias.html">mod_alias</a></code> directives (<code class="directive"><a href="../mod/mod_alias.html#redirect">Redirect</a></code>, <code class="directive"><a href="../mod/mod_alias.html#redirecttemp">RedirectTemp</a></code>, <code class="directive"><a href="../mod/mod_alias.html#redirectpermanent">RedirectPermanent</a></code>, <code class="directive"><a href="../mod/mod_alias.html#redirectmatch">RedirectMatch</a></code>), and
459 <code class="directive"><a href="../mod/mod_actions.html#action">Action</a></code> from
460 <code class="module"><a href="../mod/mod_actions.html">mod_actions</a></code>.
466 Allow use of the directives controlling directory indexing
467 (<code class="directive"><a href="../mod/mod_autoindex.html#adddescription">AddDescription</a></code>,
468 <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>,
469 <code class="directive"><a href="../mod/mod_autoindex.html#addiconbytype">AddIconByType</a></code>,
470 <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_dir.html#fallbackresource">FallbackResource</a></code>, <a href="mod_autoindex.html#indexoptions.fancyindexing"><code>FancyIndexing</code></a>, <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>,
476 Allow use of the directives controlling host access (<code class="directive"><a href="../mod/mod_access_compat.html#allow">Allow</a></code>, <code class="directive"><a href="../mod/mod_access_compat.html#deny">Deny</a></code> and <code class="directive"><a href="../mod/mod_access_compat.html#order">Order</a></code>).</dd>
481 <dt>Nonfatal=[Override|Unknown|All]</dt>
484 Allow use of AllowOverride option to treat syntax errors in
485 .htaccess as nonfatal. Instead of causing an Internal Server
486 Error, disallowed or unrecognised directives will be ignored
487 and a warning logged:
489 <li><strong>Nonfatal=Override</strong> treats directives
490 forbidden by AllowOverride as nonfatal.</li>
491 <li><strong>Nonfatal=Unknown</strong> treats unknown directives
492 as nonfatal. This covers typos and directives implemented
493 by a module that's not present.</li>
494 <li><strong>Nonfatal=All</strong> treats both the above as nonfatal.</li>
496 <p>Note that a syntax error in a valid directive will still cause
497 an internal server error.</p>
498 <div class="warning"><h3>Security</h3>
499 Nonfatal errors may have security implications for .htaccess users.
500 For example, if AllowOverride disallows AuthConfig, users'
501 configuration designed to restrict access to a site will be disabled.
505 <dt>Options[=<var>Option</var>,...]</dt>
508 Allow use of the directives controlling specific directory
509 features (<code class="directive"><a href="#options">Options</a></code> and
510 <code class="directive"><a href="../mod/mod_include.html#xbithack">XBitHack</a></code>).
511 An equal sign may be given followed by a comma-separated list, without
512 spaces, of options that may be set using the <code class="directive"><a href="#options">Options</a></code> command.
514 <div class="note"><h3>Implicit disabling of Options</h3>
515 <p>Even though the list of options that may be used in .htaccess files
516 can be limited with this directive, as long as any <code class="directive"><a href="#options">Options</a></code> directive is allowed any
517 other inherited option can be disabled by using the non-relative
518 syntax. In other words, this mechanism cannot force a specific option
519 to remain <em>set</em> while allowing any others to be set.
522 <div class="example"><p><code>
523 AllowOverride Options=Indexes,MultiViews
530 <pre class="prettyprint lang-config">AllowOverride AuthConfig Indexes</pre>
533 <p>In the example above, all directives that are neither in the group
534 <code>AuthConfig</code> nor <code>Indexes</code> cause an internal
537 <div class="note"><p>For security and performance reasons, do not set
538 <code>AllowOverride</code> to anything other than <code>None</code>
539 in your <code><Directory "/"></code> block. Instead, find (or
540 create) the <code><Directory></code> block that refers to the
541 directory where you're actually planning to place a
542 <code>.htaccess</code> file.</p>
547 <li><code class="directive"><a href="#accessfilename">AccessFileName</a></code></li>
548 <li><code class="directive"><a href="#allowoverridelist">AllowOverrideList</a></code></li>
549 <li><a href="../configuring.html">Configuration Files</a></li>
550 <li><a href="../howto/htaccess.html">.htaccess Files</a></li>
553 <div class="top"><a href="#page-header"><img alt="top" src="../images/up.gif" /></a></div>
554 <div class="directive-section"><h2><a name="AllowOverrideList" id="AllowOverrideList">AllowOverrideList</a> <a name="allowoverridelist" id="allowoverridelist">Directive</a></h2>
555 <table class="directive">
556 <tr><th><a href="directive-dict.html#Description">Description:</a></th><td>Individual directives that are allowed in
557 <code>.htaccess</code> files</td></tr>
558 <tr><th><a href="directive-dict.html#Syntax">Syntax:</a></th><td><code>AllowOverrideList None|<var>directive</var>
559 [<var>directive-type</var>] ...</code></td></tr>
560 <tr><th><a href="directive-dict.html#Default">Default:</a></th><td><code>AllowOverrideList None</code></td></tr>
561 <tr><th><a href="directive-dict.html#Context">Context:</a></th><td>directory</td></tr>
562 <tr><th><a href="directive-dict.html#Status">Status:</a></th><td>Core</td></tr>
563 <tr><th><a href="directive-dict.html#Module">Module:</a></th><td>core</td></tr>
565 <p>When the server finds an <code>.htaccess</code> file (as
566 specified by <code class="directive"><a href="#accessfilename">AccessFileName</a></code>),
567 it needs to know which directives declared in that file can override
568 earlier configuration directives.</p>
570 <div class="note"><h3>Only available in <Directory> sections</h3>
571 <code class="directive">AllowOverrideList</code> is valid only in
572 <code class="directive"><a href="#directory"><Directory></a></code>
573 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
574 <code class="directive"><a href="#files"><Files></a></code> sections.
577 <p>When this directive is set to <code>None</code> and <code class="directive"><a href="#allowoverride">AllowOverride</a></code> is set to <code>None</code>,
578 then <a href="#accessfilename">.htaccess</a> files are completely
579 ignored. In this case, the server will not even attempt to read
580 <code>.htaccess</code> files in the filesystem.</p>
584 <pre class="prettyprint lang-config">AllowOverride None
585 AllowOverrideList Redirect RedirectMatch</pre>
588 <p>In the example above, only the <code>Redirect</code> and
589 <code>RedirectMatch</code> directives are allowed. All others will
590 cause an internal server error.</p>
594 <pre class="prettyprint lang-config">AllowOverride AuthConfig
595 AllowOverrideList CookieTracking CookieName</pre>
598 <p>In the example above, <code class="directive"><a href="#allowoverride">AllowOverride
599 </a></code> grants permission to the <code>AuthConfig</code>
600 directive grouping and <code class="directive">AllowOverrideList</code> grants
601 permission to only two directives from the <code>FileInfo</code> directive
602 grouping. All others will cause an internal server error.</p>
606 <li><code class="directive"><a href="#accessfilename">AccessFileName</a></code></li>
607 <li><code class="directive"><a href="#allowoverride">AllowOverride</a></code></li>
608 <li><a href="../configuring.html">Configuration Files</a></li>
609 <li><a href="../howto/htaccess.html">.htaccess Files</a></li>
612 <div class="top"><a href="#page-header"><img alt="top" src="../images/up.gif" /></a></div>
613 <div class="directive-section"><h2><a name="CGIMapExtension" id="CGIMapExtension">CGIMapExtension</a> <a name="cgimapextension" id="cgimapextension">Directive</a></h2>
614 <table class="directive">
615 <tr><th><a href="directive-dict.html#Description">Description:</a></th><td>Technique for locating the interpreter for CGI
617 <tr><th><a href="directive-dict.html#Syntax">Syntax:</a></th><td><code>CGIMapExtension <var>cgi-path</var> <var>.extension</var></code></td></tr>
618 <tr><th><a href="directive-dict.html#Context">Context:</a></th><td>directory, .htaccess</td></tr>
619 <tr><th><a href="directive-dict.html#Override">Override:</a></th><td>FileInfo</td></tr>
620 <tr><th><a href="directive-dict.html#Status">Status:</a></th><td>Core</td></tr>
621 <tr><th><a href="directive-dict.html#Module">Module:</a></th><td>core</td></tr>
622 <tr><th><a href="directive-dict.html#Compatibility">Compatibility:</a></th><td>NetWare only</td></tr>
624 <p>This directive is used to control how Apache httpd finds the
625 interpreter used to run CGI scripts. For example, setting
626 <code>CGIMapExtension sys:\foo.nlm .foo</code> will
627 cause all CGI script files with a <code>.foo</code> extension to
628 be passed to the FOO interpreter.</p>
631 <div class="top"><a href="#page-header"><img alt="top" src="../images/up.gif" /></a></div>
632 <div class="directive-section"><h2><a name="CGIPassAuth" id="CGIPassAuth">CGIPassAuth</a> <a name="cgipassauth" id="cgipassauth">Directive</a></h2>
633 <table class="directive">
634 <tr><th><a href="directive-dict.html#Description">Description:</a></th><td>Enables passing HTTP authorization headers to scripts as CGI
636 <tr><th><a href="directive-dict.html#Syntax">Syntax:</a></th><td><code>CGIPassAuth On|Off</code></td></tr>
637 <tr><th><a href="directive-dict.html#Default">Default:</a></th><td><code>CGIPassAuth Off</code></td></tr>
638 <tr><th><a href="directive-dict.html#Context">Context:</a></th><td>directory, .htaccess</td></tr>
639 <tr><th><a href="directive-dict.html#Override">Override:</a></th><td>AuthConfig</td></tr>
640 <tr><th><a href="directive-dict.html#Status">Status:</a></th><td>Core</td></tr>
641 <tr><th><a href="directive-dict.html#Module">Module:</a></th><td>core</td></tr>
642 <tr><th><a href="directive-dict.html#Compatibility">Compatibility:</a></th><td>Available in Apache HTTP Server 2.4.13 and later</td></tr>
644 <p><code class="directive">CGIPassAuth</code> allows scripts access to HTTP
645 authorization headers such as <code>Authorization</code>, which is
646 required for scripts that implement HTTP Basic authentication.
647 Normally these HTTP headers are hidden from scripts. This is to disallow
648 scripts from seeing user ids and passwords used to access the server when
649 HTTP Basic authentication is enabled in the web server. This directive
650 should be used when scripts are allowed to implement HTTP Basic
653 <p>This directive can be used instead of the compile-time setting
654 <code>SECURITY_HOLE_PASS_AUTHORIZATION</code> which has been available
655 in previous versions of Apache HTTP Server.</p>
657 <p>The setting is respected by any modules which use
658 <code>ap_add_common_vars()</code>, such as <code class="module"><a href="../mod/mod_cgi.html">mod_cgi</a></code>,
659 <code class="module"><a href="../mod/mod_cgid.html">mod_cgid</a></code>, <code class="module"><a href="../mod/mod_proxy_fcgi.html">mod_proxy_fcgi</a></code>,
660 <code class="module"><a href="../mod/mod_proxy_scgi.html">mod_proxy_scgi</a></code>, and so on. Notably, it affects
661 modules which don't handle the request in the usual sense but
662 still use this API; examples of this are <code class="module"><a href="../mod/mod_include.html">mod_include</a></code>
663 and <code class="module"><a href="../mod/mod_ext_filter.html">mod_ext_filter</a></code>. Third-party modules that don't
664 use <code>ap_add_common_vars()</code> may choose to respect the setting
668 <div class="top"><a href="#page-header"><img alt="top" src="../images/up.gif" /></a></div>
669 <div class="directive-section"><h2><a name="ContentDigest" id="ContentDigest">ContentDigest</a> <a name="contentdigest" id="contentdigest">Directive</a></h2>
670 <table class="directive">
671 <tr><th><a href="directive-dict.html#Description">Description:</a></th><td>Enables the generation of <code>Content-MD5</code> HTTP Response
673 <tr><th><a href="directive-dict.html#Syntax">Syntax:</a></th><td><code>ContentDigest On|Off</code></td></tr>
674 <tr><th><a href="directive-dict.html#Default">Default:</a></th><td><code>ContentDigest Off</code></td></tr>
675 <tr><th><a href="directive-dict.html#Context">Context:</a></th><td>server config, virtual host, directory, .htaccess</td></tr>
676 <tr><th><a href="directive-dict.html#Override">Override:</a></th><td>Options</td></tr>
677 <tr><th><a href="directive-dict.html#Status">Status:</a></th><td>Core</td></tr>
678 <tr><th><a href="directive-dict.html#Module">Module:</a></th><td>core</td></tr>
680 <p>This directive enables the generation of
681 <code>Content-MD5</code> headers as defined in RFC1864
682 respectively RFC2616.</p>
684 <p>MD5 is an algorithm for computing a "message digest"
685 (sometimes called "fingerprint") of arbitrary-length data, with
686 a high degree of confidence that any alterations in the data
687 will be reflected in alterations in the message digest.</p>
689 <p>The <code>Content-MD5</code> header provides an end-to-end
690 message integrity check (MIC) of the entity-body. A proxy or
691 client may check this header for detecting accidental
692 modification of the entity-body in transit. Example header:</p>
694 <div class="example"><p><code>
695 Content-MD5: AuLb7Dp1rqtRtxz2m9kRpA==
698 <p>Note that this can cause performance problems on your server
699 since the message digest is computed on every request (the
700 values are not cached).</p>
702 <p><code>Content-MD5</code> is only sent for documents served
703 by the <code class="module"><a href="../mod/core.html">core</a></code>, and not by any module. For example,
704 SSI documents, output from CGI scripts, and byte range responses
705 do not have this header.</p>
708 <div class="top"><a href="#page-header"><img alt="top" src="../images/up.gif" /></a></div>
709 <div class="directive-section"><h2><a name="DefaultRuntimeDir" id="DefaultRuntimeDir">DefaultRuntimeDir</a> <a name="defaultruntimedir" id="defaultruntimedir">Directive</a></h2>
710 <table class="directive">
711 <tr><th><a href="directive-dict.html#Description">Description:</a></th><td>Base directory for the server run-time files</td></tr>
712 <tr><th><a href="directive-dict.html#Syntax">Syntax:</a></th><td><code>DefaultRuntimeDir <var>directory-path</var></code></td></tr>
713 <tr><th><a href="directive-dict.html#Default">Default:</a></th><td><code>DefaultRuntimeDir DEFAULT_REL_RUNTIMEDIR (logs/)</code></td></tr>
714 <tr><th><a href="directive-dict.html#Context">Context:</a></th><td>server config</td></tr>
715 <tr><th><a href="directive-dict.html#Status">Status:</a></th><td>Core</td></tr>
716 <tr><th><a href="directive-dict.html#Module">Module:</a></th><td>core</td></tr>
717 <tr><th><a href="directive-dict.html#Compatibility">Compatibility:</a></th><td>Available in Apache 2.4.2 and later</td></tr>
719 <p>The <code class="directive">DefaultRuntimeDir</code> directive sets the
720 directory in which the server will create various run-time files
721 (shared memory, locks, etc.). If set as a relative path, the full path
722 will be relative to <code class="directive">ServerRoot</code>.</p>
724 <p><strong>Example</strong></p>
725 <pre class="prettyprint lang-config">DefaultRuntimeDir scratch/</pre>
728 <p>The default location of <code class="directive">DefaultRuntimeDir</code> may be
729 modified by changing the <code>DEFAULT_REL_RUNTIMEDIR</code> #define
732 <p>Note: <code class="directive">ServerRoot</code> should be specified before this
733 directive is used. Otherwise, the default value of <code class="directive">ServerRoot</code>
734 would be used to set the base directory.</p>
739 <li><a href="../misc/security_tips.html#serverroot">the
740 security tips</a> for information on how to properly set
741 permissions on the <code class="directive">ServerRoot</code></li>
744 <div class="top"><a href="#page-header"><img alt="top" src="../images/up.gif" /></a></div>
745 <div class="directive-section"><h2><a name="DefaultType" id="DefaultType">DefaultType</a> <a name="defaulttype" id="defaulttype">Directive</a></h2>
746 <table class="directive">
747 <tr><th><a href="directive-dict.html#Description">Description:</a></th><td>This directive has no effect other than to emit warnings
748 if the value is not <code>none</code>. In prior versions, DefaultType
749 would specify a default media type to assign to response content for
750 which no other media type configuration could be found.
752 <tr><th><a href="directive-dict.html#Syntax">Syntax:</a></th><td><code>DefaultType <var>media-type|none</var></code></td></tr>
753 <tr><th><a href="directive-dict.html#Default">Default:</a></th><td><code>DefaultType none</code></td></tr>
754 <tr><th><a href="directive-dict.html#Context">Context:</a></th><td>server config, virtual host, directory, .htaccess</td></tr>
755 <tr><th><a href="directive-dict.html#Override">Override:</a></th><td>FileInfo</td></tr>
756 <tr><th><a href="directive-dict.html#Status">Status:</a></th><td>Core</td></tr>
757 <tr><th><a href="directive-dict.html#Module">Module:</a></th><td>core</td></tr>
758 <tr><th><a href="directive-dict.html#Compatibility">Compatibility:</a></th><td>All choices except <code>none</code> are DISABLED for 2.3.x and later.
761 <p>This directive has been disabled. For backwards compatibility
762 of configuration files, it may be specified with the value
763 <code>none</code>, meaning no default media type. For example:</p>
765 <pre class="prettyprint lang-config">DefaultType None</pre>
768 <p><code>DefaultType None</code> is only available in
769 httpd-2.2.7 and later.</p>
771 <p>Use the mime.types configuration file and the
772 <code class="directive"><a href="../mod/mod_mime.html#addtype">AddType</a></code> to configure media
773 type assignments via file extensions, or the
774 <code class="directive"><a href="#forcetype">ForceType</a></code> directive to configure
775 the media type for specific resources. Otherwise, the server will
776 send the response without a Content-Type header field and the
777 recipient may attempt to guess the media type.</p>
780 <div class="top"><a href="#page-header"><img alt="top" src="../images/up.gif" /></a></div>
781 <div class="directive-section"><h2><a name="Define" id="Define">Define</a> <a name="define" id="define">Directive</a></h2>
782 <table class="directive">
783 <tr><th><a href="directive-dict.html#Description">Description:</a></th><td>Define a variable</td></tr>
784 <tr><th><a href="directive-dict.html#Syntax">Syntax:</a></th><td><code>Define <var>parameter-name</var> [<var>parameter-value</var>]</code></td></tr>
785 <tr><th><a href="directive-dict.html#Context">Context:</a></th><td>server config, virtual host</td></tr>
786 <tr><th><a href="directive-dict.html#Status">Status:</a></th><td>Core</td></tr>
787 <tr><th><a href="directive-dict.html#Module">Module:</a></th><td>core</td></tr>
789 <p>In its one parameter form, <code class="directive">Define</code> is equivalent
790 to passing the <code>-D</code> argument to <code class="program"><a href="../programs/httpd.html">httpd</a></code>. It
791 can be used to toggle the use of
792 <code class="directive"><a href="#ifdefine"><IfDefine></a></code> sections
793 without needing to alter <code>-D</code> arguments in any startup
796 <p>In addition to that, if the second parameter is given, a config variable
797 is set to this value. The variable can be used in the configuration using
798 the <code>${VAR}</code> syntax. The variable is always globally defined
799 and not limited to the scope of the surrounding config section.</p>
801 <pre class="prettyprint lang-config"><IfDefine TEST>
802 Define servername test.example.com
804 <IfDefine !TEST>
805 Define servername www.example.com
809 DocumentRoot "/var/www/${servername}/htdocs"</pre>
812 <p>Variable names may not contain colon ":" characters, to avoid clashes
813 with <code class="directive"><a href="../mod/mod_rewrite.html#rewritemap">RewriteMap</a></code>'s syntax.</p>
815 <p>While this directive is supported in virtual host context,
816 the changes it makes are visible to any later configuration
817 directives, beyond any enclosing virtual host</p>
820 <div class="top"><a href="#page-header"><img alt="top" src="../images/up.gif" /></a></div>
821 <div class="directive-section"><h2><a name="Directory" id="Directory"><Directory></a> <a name="directory" id="directory">Directive</a></h2>
822 <table class="directive">
823 <tr><th><a href="directive-dict.html#Description">Description:</a></th><td>Enclose a group of directives that apply only to the
824 named file-system directory, sub-directories, and their contents.</td></tr>
825 <tr><th><a href="directive-dict.html#Syntax">Syntax:</a></th><td><code><Directory <var>directory-path</var>>
826 ... </Directory></code></td></tr>
827 <tr><th><a href="directive-dict.html#Context">Context:</a></th><td>server config, virtual host</td></tr>
828 <tr><th><a href="directive-dict.html#Status">Status:</a></th><td>Core</td></tr>
829 <tr><th><a href="directive-dict.html#Module">Module:</a></th><td>core</td></tr>
831 <p><code class="directive"><Directory></code> and
832 <code></Directory></code> are used to enclose a group of
833 directives that will apply only to the named directory,
834 sub-directories of that directory, and the files within the respective
835 directories. Any directive that is allowed
836 in a directory context may be used. <var>Directory-path</var> is
837 either the full path to a directory, or a wild-card string using
838 Unix shell-style matching. In a wild-card string, <code>?</code> matches
839 any single character, and <code>*</code> matches any sequences of
840 characters. You may also use <code>[]</code> character ranges. None
841 of the wildcards match a `/' character, so <code><Directory
842 "/*/public_html"></code> will not match
843 <code>/home/user/public_html</code>, but <code><Directory
844 "/home/*/public_html"></code> will match. Example:</p>
846 <pre class="prettyprint lang-config"><Directory "/usr/local/httpd/htdocs">
847 Options Indexes FollowSymLinks
848 </Directory></pre>
851 <p>Directory paths <em>may</em> be quoted, if you like, however, it
852 <em>must</em> be quoted if the path contains spaces. This is because a
853 space would otherwise indicate the end of an argument.</p>
856 <p>Be careful with the <var>directory-path</var> arguments:
857 They have to literally match the filesystem path which Apache httpd uses
858 to access the files. Directives applied to a particular
859 <code><Directory></code> will not apply to files accessed from
860 that same directory via a different path, such as via different symbolic
864 <p><a class="glossarylink" href="../glossary.html#regex" title="see glossary">Regular
865 expressions</a> can also be used, with the addition of the
866 <code>~</code> character. For example:</p>
868 <pre class="prettyprint lang-config"><Directory ~ "^/www/[0-9]{3}">
870 </Directory></pre>
873 <p>would match directories in <code>/www/</code> that consisted of
876 <p>If multiple (non-regular expression) <code class="directive"><Directory></code> sections
877 match the directory (or one of its parents) containing a document,
878 then the directives are applied in the order of shortest match
879 first, interspersed with the directives from the <a href="#accessfilename">.htaccess</a> files. For example,
882 <pre class="prettyprint lang-config"><Directory "/">
886 <Directory "/home">
887 AllowOverride FileInfo
888 </Directory></pre>
891 <p>for access to the document <code>/home/web/dir/doc.html</code>
895 <li>Apply directive <code>AllowOverride None</code>
896 (disabling <code>.htaccess</code> files).</li>
898 <li>Apply directive <code>AllowOverride FileInfo</code> (for
899 directory <code>/home</code>).</li>
901 <li>Apply any <code>FileInfo</code> directives in
902 <code>/home/.htaccess</code>, <code>/home/web/.htaccess</code> and
903 <code>/home/web/dir/.htaccess</code> in that order.</li>
906 <p>Regular expressions are not considered until after all of the
907 normal sections have been applied. Then all of the regular
908 expressions are tested in the order they appeared in the
909 configuration file. For example, with</p>
911 <pre class="prettyprint lang-config"><Directory ~ "abc$">
912 # ... directives here ...
913 </Directory></pre>
916 <p>the regular expression section won't be considered until after
917 all normal <code class="directive"><Directory></code>s and
918 <code>.htaccess</code> files have been applied. Then the regular
919 expression will match on <code>/home/abc/public_html/abc</code> and
920 the corresponding <code class="directive"><Directory></code> will
923 <p><strong>Note that the default access for
924 <code><Directory "/"></code> is to permit all access.
925 This means that Apache httpd will serve any file mapped from an URL. It is
926 recommended that you change this with a block such
929 <pre class="prettyprint lang-config"><Directory "/">
931 </Directory></pre>
934 <p><strong>and then override this for directories you
935 <em>want</em> accessible. See the <a href="../misc/security_tips.html">Security Tips</a> page for more
936 details.</strong></p>
938 <p>The directory sections occur in the <code>httpd.conf</code> file.
939 <code class="directive"><Directory></code> directives
940 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>
944 <li><a href="../sections.html">How <Directory>,
945 <Location> and <Files> sections work</a> for an
946 explanation of how these different sections are combined when a
947 request is received</li>
950 <div class="top"><a href="#page-header"><img alt="top" src="../images/up.gif" /></a></div>
951 <div class="directive-section"><h2><a name="DirectoryMatch" id="DirectoryMatch"><DirectoryMatch></a> <a name="directorymatch" id="directorymatch">Directive</a></h2>
952 <table class="directive">
953 <tr><th><a href="directive-dict.html#Description">Description:</a></th><td>Enclose directives that apply to
954 the contents of file-system directories matching a regular expression.</td></tr>
955 <tr><th><a href="directive-dict.html#Syntax">Syntax:</a></th><td><code><DirectoryMatch <var>regex</var>>
956 ... </DirectoryMatch></code></td></tr>
957 <tr><th><a href="directive-dict.html#Context">Context:</a></th><td>server config, virtual host</td></tr>
958 <tr><th><a href="directive-dict.html#Status">Status:</a></th><td>Core</td></tr>
959 <tr><th><a href="directive-dict.html#Module">Module:</a></th><td>core</td></tr>
961 <p><code class="directive"><DirectoryMatch></code> and
962 <code></DirectoryMatch></code> are used to enclose a group
963 of directives which will apply only to the named directory (and the files within),
964 the same as <code class="directive"><a href="#directory"><Directory></a></code>.
965 However, it takes as an argument a
966 <a class="glossarylink" href="../glossary.html#regex" title="see glossary">regular expression</a>. For example:</p>
968 <pre class="prettyprint lang-config"><DirectoryMatch "^/www/(.+/)?[0-9]{3}/">
970 </DirectoryMatch></pre>
973 <p>matches directories in <code>/www/</code> (or any subdirectory thereof)
974 that consist of three numbers.</p>
976 <div class="note"><h3>Compatability</h3>
977 Prior to 2.3.9, this directive implicitly applied to sub-directories
978 (like <code class="directive"><a href="#directory"><Directory></a></code>) and
979 could not match the end of line symbol ($). In 2.3.9 and later,
980 only directories that match the expression are affected by the enclosed
984 <div class="note"><h3>Trailing Slash</h3>
985 This directive applies to requests for directories that may or may
986 not end in a trailing slash, so expressions that are anchored to the
987 end of line ($) must be written with care.
990 <p>From 2.4.8 onwards, named groups and backreferences are captured and
991 written to the environment with the corresponding name prefixed with
992 "MATCH_" and in upper case. This allows elements of paths to be referenced
993 from within <a href="../expr.html">expressions</a> and modules like
994 <code class="module"><a href="../mod/mod_rewrite.html">mod_rewrite</a></code>. In order to prevent confusion, numbered
995 (unnamed) backreferences are ignored. Use named groups instead.</p>
997 <pre class="prettyprint lang-config"><DirectoryMatch "^/var/www/combined/(?<sitename>[^/]+)">
998 Require ldap-group cn=%{env:MATCH_SITENAME},ou=combined,o=Example
999 </DirectoryMatch></pre>
1004 <li><code class="directive"><a href="#directory"><Directory></a></code> for
1005 a description of how regular expressions are mixed in with normal
1006 <code class="directive"><Directory></code>s</li>
1007 <li><a href="../sections.html">How <Directory>, <Location> and
1008 <Files> sections work</a> for an explanation of how these different
1009 sections are combined when a request is received</li>
1012 <div class="top"><a href="#page-header"><img alt="top" src="../images/up.gif" /></a></div>
1013 <div class="directive-section"><h2><a name="DocumentRoot" id="DocumentRoot">DocumentRoot</a> <a name="documentroot" id="documentroot">Directive</a></h2>
1014 <table class="directive">
1015 <tr><th><a href="directive-dict.html#Description">Description:</a></th><td>Directory that forms the main document tree visible
1016 from the web</td></tr>
1017 <tr><th><a href="directive-dict.html#Syntax">Syntax:</a></th><td><code>DocumentRoot <var>directory-path</var></code></td></tr>
1018 <tr><th><a href="directive-dict.html#Default">Default:</a></th><td><code>DocumentRoot /usr/local/apache/htdocs</code></td></tr>
1019 <tr><th><a href="directive-dict.html#Context">Context:</a></th><td>server config, virtual host</td></tr>
1020 <tr><th><a href="directive-dict.html#Status">Status:</a></th><td>Core</td></tr>
1021 <tr><th><a href="directive-dict.html#Module">Module:</a></th><td>core</td></tr>
1023 <p>This directive sets the directory from which <code class="program"><a href="../programs/httpd.html">httpd</a></code>
1024 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
1025 path from the requested URL to the document root to make the
1026 path to the document. Example:</p>
1028 <pre class="prettyprint lang-config">DocumentRoot "/usr/web"</pre>
1031 <p>then an access to
1032 <code>http://my.example.com/index.html</code> refers to
1033 <code>/usr/web/index.html</code>. If the <var>directory-path</var> is
1034 not absolute then it is assumed to be relative to the <code class="directive"><a href="#serverroot">ServerRoot</a></code>.</p>
1036 <p>The <code class="directive">DocumentRoot</code> should be specified without
1037 a trailing slash.</p>
1041 <li><a href="../urlmapping.html#documentroot">Mapping URLs to Filesystem
1045 <div class="top"><a href="#page-header"><img alt="top" src="../images/up.gif" /></a></div>
1046 <div class="directive-section"><h2><a name="Else" id="Else"><Else></a> <a name="else" id="else">Directive</a></h2>
1047 <table class="directive">
1048 <tr><th><a href="directive-dict.html#Description">Description:</a></th><td>Contains directives that apply only if the condition of a
1049 previous <code class="directive"><a href="#if"><If></a></code> or
1050 <code class="directive"><a href="#elseif"><ElseIf></a></code> section is not
1051 satisfied by a request at runtime</td></tr>
1052 <tr><th><a href="directive-dict.html#Syntax">Syntax:</a></th><td><code><Else> ... </Else></code></td></tr>
1053 <tr><th><a href="directive-dict.html#Context">Context:</a></th><td>server config, virtual host, directory, .htaccess</td></tr>
1054 <tr><th><a href="directive-dict.html#Override">Override:</a></th><td>All</td></tr>
1055 <tr><th><a href="directive-dict.html#Status">Status:</a></th><td>Core</td></tr>
1056 <tr><th><a href="directive-dict.html#Module">Module:</a></th><td>core</td></tr>
1058 <p>The <code class="directive"><Else></code> applies the enclosed
1059 directives if and only if the most recent
1060 <code class="directive"><If></code> or
1061 <code class="directive"><ElseIf></code> section
1062 in the same scope has not been applied.
1063 For example: In </p>
1065 <pre class="prettyprint lang-config"><If "-z req('Host')">
1073 <p> The <code class="directive"><If></code> would match HTTP/1.0
1074 requests without a <var>Host:</var> header and the
1075 <code class="directive"><Else></code> would match requests
1076 with a <var>Host:</var> header.</p>
1081 <li><code class="directive"><a href="#if"><If></a></code></li>
1082 <li><code class="directive"><a href="#elseif"><ElseIf></a></code></li>
1083 <li><a href="../sections.html">How <Directory>, <Location>,
1084 <Files> sections work</a> for an explanation of how these
1085 different sections are combined when a request is received.
1086 <code class="directive"><If></code>,
1087 <code class="directive"><ElseIf></code>, and
1088 <code class="directive"><Else></code> are applied last.</li>
1091 <div class="top"><a href="#page-header"><img alt="top" src="../images/up.gif" /></a></div>
1092 <div class="directive-section"><h2><a name="ElseIf" id="ElseIf"><ElseIf></a> <a name="elseif" id="elseif">Directive</a></h2>
1093 <table class="directive">
1094 <tr><th><a href="directive-dict.html#Description">Description:</a></th><td>Contains directives that apply only if a condition is satisfied
1095 by a request at runtime while the condition of a previous
1096 <code class="directive"><a href="#if"><If></a></code> or
1097 <code class="directive"><ElseIf></code> section is not
1099 <tr><th><a href="directive-dict.html#Syntax">Syntax:</a></th><td><code><ElseIf <var>expression</var>> ... </ElseIf></code></td></tr>
1100 <tr><th><a href="directive-dict.html#Context">Context:</a></th><td>server config, virtual host, directory, .htaccess</td></tr>
1101 <tr><th><a href="directive-dict.html#Override">Override:</a></th><td>All</td></tr>
1102 <tr><th><a href="directive-dict.html#Status">Status:</a></th><td>Core</td></tr>
1103 <tr><th><a href="directive-dict.html#Module">Module:</a></th><td>core</td></tr>
1105 <p>The <code class="directive"><ElseIf></code> applies the enclosed
1106 directives if and only if both the given condition evaluates to true and
1107 the most recent <code class="directive"><If></code> or
1108 <code class="directive"><ElseIf></code> section in the same scope has
1109 not been applied. For example: In </p>
1111 <pre class="prettyprint lang-config"><If "-R '10.1.0.0/16'">
1114 <ElseIf "-R '10.0.0.0/8'">
1122 <p>The <code class="directive"><ElseIf></code> would match if
1123 the remote address of a request belongs to the subnet 10.0.0.0/8 but
1124 not to the subnet 10.1.0.0/16.</p>
1129 <li><a href="../expr.html">Expressions in Apache HTTP Server</a>,
1130 for a complete reference and more examples.</li>
1131 <li><code class="directive"><a href="#if"><If></a></code></li>
1132 <li><code class="directive"><a href="#else"><Else></a></code></li>
1133 <li><a href="../sections.html">How <Directory>, <Location>,
1134 <Files> sections work</a> for an explanation of how these
1135 different sections are combined when a request is received.
1136 <code class="directive"><If></code>,
1137 <code class="directive"><ElseIf></code>, and
1138 <code class="directive"><Else></code> are applied last.</li>
1141 <div class="top"><a href="#page-header"><img alt="top" src="../images/up.gif" /></a></div>
1142 <div class="directive-section"><h2><a name="EnableMMAP" id="EnableMMAP">EnableMMAP</a> <a name="enablemmap" id="enablemmap">Directive</a></h2>
1143 <table class="directive">
1144 <tr><th><a href="directive-dict.html#Description">Description:</a></th><td>Use memory-mapping to read files during delivery</td></tr>
1145 <tr><th><a href="directive-dict.html#Syntax">Syntax:</a></th><td><code>EnableMMAP On|Off</code></td></tr>
1146 <tr><th><a href="directive-dict.html#Default">Default:</a></th><td><code>EnableMMAP On</code></td></tr>
1147 <tr><th><a href="directive-dict.html#Context">Context:</a></th><td>server config, virtual host, directory, .htaccess</td></tr>
1148 <tr><th><a href="directive-dict.html#Override">Override:</a></th><td>FileInfo</td></tr>
1149 <tr><th><a href="directive-dict.html#Status">Status:</a></th><td>Core</td></tr>
1150 <tr><th><a href="directive-dict.html#Module">Module:</a></th><td>core</td></tr>
1152 <p>This directive controls whether the <code class="program"><a href="../programs/httpd.html">httpd</a></code> may use
1153 memory-mapping if it needs to read the contents of a file during
1154 delivery. By default, when the handling of a request requires
1155 access to the data within a file -- for example, when delivering a
1156 server-parsed file using <code class="module"><a href="../mod/mod_include.html">mod_include</a></code> -- Apache httpd
1157 memory-maps the file if the OS supports it.</p>
1159 <p>This memory-mapping sometimes yields a performance improvement.
1160 But in some environments, it is better to disable the memory-mapping
1161 to prevent operational problems:</p>
1164 <li>On some multiprocessor systems, memory-mapping can reduce the
1165 performance of the <code class="program"><a href="../programs/httpd.html">httpd</a></code>.</li>
1166 <li>Deleting or truncating a file while <code class="program"><a href="../programs/httpd.html">httpd</a></code>
1167 has it memory-mapped can cause <code class="program"><a href="../programs/httpd.html">httpd</a></code> to
1168 crash with a segmentation fault.
1172 <p>For server configurations that are vulnerable to these problems,
1173 you should disable memory-mapping of delivered files by specifying:</p>
1175 <pre class="prettyprint lang-config">EnableMMAP Off</pre>
1178 <p>For NFS mounted files, this feature may be disabled explicitly for
1179 the offending files by specifying:</p>
1181 <pre class="prettyprint lang-config"><Directory "/path-to-nfs-files">
1183 </Directory></pre>
1187 <div class="top"><a href="#page-header"><img alt="top" src="../images/up.gif" /></a></div>
1188 <div class="directive-section"><h2><a name="EnableSendfile" id="EnableSendfile">EnableSendfile</a> <a name="enablesendfile" id="enablesendfile">Directive</a></h2>
1189 <table class="directive">
1190 <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>
1191 <tr><th><a href="directive-dict.html#Syntax">Syntax:</a></th><td><code>EnableSendfile On|Off</code></td></tr>
1192 <tr><th><a href="directive-dict.html#Default">Default:</a></th><td><code>EnableSendfile Off</code></td></tr>
1193 <tr><th><a href="directive-dict.html#Context">Context:</a></th><td>server config, virtual host, directory, .htaccess</td></tr>
1194 <tr><th><a href="directive-dict.html#Override">Override:</a></th><td>FileInfo</td></tr>
1195 <tr><th><a href="directive-dict.html#Status">Status:</a></th><td>Core</td></tr>
1196 <tr><th><a href="directive-dict.html#Module">Module:</a></th><td>core</td></tr>
1197 <tr><th><a href="directive-dict.html#Compatibility">Compatibility:</a></th><td>Default changed to Off in
1198 version 2.3.9.</td></tr>
1200 <p>This directive controls whether <code class="program"><a href="../programs/httpd.html">httpd</a></code> may use the
1201 sendfile support from the kernel to transmit file contents to the client.
1202 By default, when the handling of a request requires no access
1203 to the data within a file -- for example, when delivering a
1204 static file -- Apache httpd uses sendfile to deliver the file contents
1205 without ever reading the file if the OS supports it.</p>
1207 <p>This sendfile mechanism avoids separate read and send operations,
1208 and buffer allocations. But on some platforms or within some
1209 filesystems, it is better to disable this feature to avoid
1210 operational problems:</p>
1213 <li>Some platforms may have broken sendfile support that the build
1214 system did not detect, especially if the binaries were built on
1215 another box and moved to such a machine with broken sendfile
1217 <li>On Linux the use of sendfile triggers TCP-checksum
1218 offloading bugs on certain networking cards when using IPv6.</li>
1219 <li>On Linux on Itanium, <code>sendfile</code> may be unable to handle
1220 files over 2GB in size.</li>
1221 <li>With a network-mounted <code class="directive"><a href="#documentroot">DocumentRoot</a></code> (e.g., NFS, SMB, CIFS, FUSE),
1222 the kernel may be unable to serve the network file through
1226 <p>For server configurations that are not vulnerable to these problems,
1227 you may enable this feature by specifying:</p>
1229 <pre class="prettyprint lang-config">EnableSendfile On</pre>
1232 <p>For network mounted files, this feature may be disabled explicitly
1233 for the offending files by specifying:</p>
1235 <pre class="prettyprint lang-config"><Directory "/path-to-nfs-files">
1237 </Directory></pre>
1239 <p>Please note that the per-directory and .htaccess configuration
1240 of <code class="directive">EnableSendfile</code> is not supported by
1241 <code class="module"><a href="../mod/mod_cache_disk.html">mod_cache_disk</a></code>.
1242 Only global definition of <code class="directive">EnableSendfile</code>
1243 is taken into account by the module.
1247 <div class="top"><a href="#page-header"><img alt="top" src="../images/up.gif" /></a></div>
1248 <div class="directive-section"><h2><a name="Error" id="Error">Error</a> <a name="error" id="error">Directive</a></h2>
1249 <table class="directive">
1250 <tr><th><a href="directive-dict.html#Description">Description:</a></th><td>Abort configuration parsing with a custom error message</td></tr>
1251 <tr><th><a href="directive-dict.html#Syntax">Syntax:</a></th><td><code>Error <var>message</var></code></td></tr>
1252 <tr><th><a href="directive-dict.html#Context">Context:</a></th><td>server config, virtual host, directory, .htaccess</td></tr>
1253 <tr><th><a href="directive-dict.html#Status">Status:</a></th><td>Core</td></tr>
1254 <tr><th><a href="directive-dict.html#Module">Module:</a></th><td>core</td></tr>
1255 <tr><th><a href="directive-dict.html#Compatibility">Compatibility:</a></th><td>2.3.9 and later</td></tr>
1257 <p>If an error can be detected within the configuration, this
1258 directive can be used to generate a custom error message, and halt
1259 configuration parsing. The typical use is for reporting required
1260 modules which are missing from the configuration.</p>
1262 <pre class="prettyprint lang-config"># Example
1263 # ensure that mod_include is loaded
1264 <IfModule !include_module>
1265 Error "mod_include is required by mod_foo. Load it with LoadModule."
1268 # ensure that exactly one of SSL,NOSSL is defined
1269 <IfDefine SSL>
1270 <IfDefine NOSSL>
1271 Error "Both SSL and NOSSL are defined. Define only one of them."
1274 <IfDefine !SSL>
1275 <IfDefine !NOSSL>
1276 Error "Either SSL or NOSSL must be defined."
1278 </IfDefine></pre>
1283 <div class="top"><a href="#page-header"><img alt="top" src="../images/up.gif" /></a></div>
1284 <div class="directive-section"><h2><a name="ErrorDocument" id="ErrorDocument">ErrorDocument</a> <a name="errordocument" id="errordocument">Directive</a></h2>
1285 <table class="directive">
1286 <tr><th><a href="directive-dict.html#Description">Description:</a></th><td>What the server will return to the client
1287 in case of an error</td></tr>
1288 <tr><th><a href="directive-dict.html#Syntax">Syntax:</a></th><td><code>ErrorDocument <var>error-code</var> <var>document</var></code></td></tr>
1289 <tr><th><a href="directive-dict.html#Context">Context:</a></th><td>server config, virtual host, directory, .htaccess</td></tr>
1290 <tr><th><a href="directive-dict.html#Override">Override:</a></th><td>FileInfo</td></tr>
1291 <tr><th><a href="directive-dict.html#Status">Status:</a></th><td>Core</td></tr>
1292 <tr><th><a href="directive-dict.html#Module">Module:</a></th><td>core</td></tr>
1294 <p>In the event of a problem or error, Apache httpd can be configured
1295 to do one of four things,</p>
1298 <li>output a simple hardcoded error message</li>
1300 <li>output a customized message</li>
1302 <li>internally redirect to a local <var>URL-path</var> to handle the
1305 <li>redirect to an external <var>URL</var> to handle the
1309 <p>The first option is the default, while options 2-4 are
1310 configured using the <code class="directive">ErrorDocument</code>
1311 directive, which is followed by the HTTP response code and a URL
1312 or a message. Apache httpd will sometimes offer additional information
1313 regarding the problem/error.</p>
1315 <p>From 2.4.13, <a href="../expr.html">expression syntax</a> can be
1316 used inside the directive to produce dynamic strings and URLs.</p>
1318 <p>URLs can begin with a slash (/) for local web-paths (relative
1319 to the <code class="directive"><a href="#documentroot">DocumentRoot</a></code>), or be a
1320 full URL which the client can resolve. Alternatively, a message
1321 can be provided to be displayed by the browser. Note that deciding
1322 whether the parameter is an URL, a path or a message is performed
1323 before any expression is parsed. Examples:</p>
1325 <pre class="prettyprint lang-config">ErrorDocument 500 http://foo.example.com/cgi-bin/tester
1326 ErrorDocument 404 /cgi-bin/bad_urls.pl
1327 ErrorDocument 401 /subscription_info.html
1328 ErrorDocument 403 "Sorry can't allow you access today"
1329 ErrorDocument 403 Forbidden!
1330 ErrorDocument 403 /cgi-bin/forbidden.pl?referrer=%{escape:%{HTTP_REFERER}}</pre>
1333 <p>Additionally, the special value <code>default</code> can be used
1334 to specify Apache httpd's simple hardcoded message. While not required
1335 under normal circumstances, <code>default</code> will restore
1336 Apache httpd's simple hardcoded message for configurations that would
1337 otherwise inherit an existing <code class="directive">ErrorDocument</code>.</p>
1339 <pre class="prettyprint lang-config">ErrorDocument 404 /cgi-bin/bad_urls.pl
1341 <Directory "/web/docs">
1342 ErrorDocument 404 default
1343 </Directory></pre>
1346 <p>Note that when you specify an <code class="directive">ErrorDocument</code>
1347 that points to a remote URL (ie. anything with a method such as
1348 <code>http</code> in front of it), Apache HTTP Server will send a redirect to the
1349 client to tell it where to find the document, even if the
1350 document ends up being on the same server. This has several
1351 implications, the most important being that the client will not
1352 receive the original error status code, but instead will
1353 receive a redirect status code. This in turn can confuse web
1354 robots and other clients which try to determine if a URL is
1355 valid using the status code. In addition, if you use a remote
1356 URL in an <code>ErrorDocument 401</code>, the client will not
1357 know to prompt the user for a password since it will not
1358 receive the 401 status code. Therefore, <strong>if you use an
1359 <code>ErrorDocument 401</code> directive, then it must refer to a local
1360 document.</strong></p>
1362 <p>Microsoft Internet Explorer (MSIE) will by default ignore
1363 server-generated error messages when they are "too small" and substitute
1364 its own "friendly" error messages. The size threshold varies depending on
1365 the type of error, but in general, if you make your error document
1366 greater than 512 bytes, then MSIE will show the server-generated
1367 error rather than masking it. More information is available in
1368 Microsoft Knowledge Base article <a href="http://support.microsoft.com/default.aspx?scid=kb;en-us;Q294807">Q294807</a>.</p>
1370 <p>Although most error messages can be overridden, there are certain
1371 circumstances where the internal messages are used regardless of the
1372 setting of <code class="directive"><a href="#errordocument">ErrorDocument</a></code>. In
1373 particular, if a malformed request is detected, normal request processing
1374 will be immediately halted and the internal error message returned.
1375 This is necessary to guard against security problems caused by
1378 <p>If you are using mod_proxy, you may wish to enable
1379 <code class="directive"><a href="../mod/mod_proxy.html#proxyerroroverride">ProxyErrorOverride</a></code> so that you can provide
1380 custom error messages on behalf of your Origin servers. If you don't enable ProxyErrorOverride,
1381 Apache httpd will not generate custom error documents for proxied content.</p>
1385 <li><a href="../custom-error.html">documentation of
1386 customizable responses</a></li>
1389 <div class="top"><a href="#page-header"><img alt="top" src="../images/up.gif" /></a></div>
1390 <div class="directive-section"><h2><a name="ErrorLog" id="ErrorLog">ErrorLog</a> <a name="errorlog" id="errorlog">Directive</a></h2>
1391 <table class="directive">
1392 <tr><th><a href="directive-dict.html#Description">Description:</a></th><td>Location where the server will log errors</td></tr>
1393 <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>
1394 <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>
1395 <tr><th><a href="directive-dict.html#Context">Context:</a></th><td>server config, virtual host</td></tr>
1396 <tr><th><a href="directive-dict.html#Status">Status:</a></th><td>Core</td></tr>
1397 <tr><th><a href="directive-dict.html#Module">Module:</a></th><td>core</td></tr>
1399 <p>The <code class="directive">ErrorLog</code> directive sets the name of
1400 the file to which the server will log any errors it encounters. If
1401 the <var>file-path</var> is not absolute then it is assumed to be
1402 relative to the <code class="directive"><a href="#serverroot">ServerRoot</a></code>.</p>
1404 <pre class="prettyprint lang-config">ErrorLog "/var/log/httpd/error_log"</pre>
1407 <p>If the <var>file-path</var>
1408 begins with a pipe character "<code>|</code>" then it is assumed to be a
1409 command to spawn to handle the error log.</p>
1411 <pre class="prettyprint lang-config">ErrorLog "|/usr/local/bin/httpd_errors"</pre>
1414 <p>See the notes on <a href="../logs.html#piped">piped logs</a> for
1415 more information.</p>
1417 <p>Using <code>syslog</code> instead of a filename enables logging
1418 via syslogd(8) if the system supports it and if <code class="module"><a href="../mod/mod_syslog.html">mod_syslog</a></code>
1419 is loaded. The default is to use syslog facility <code>local7</code>,
1420 but you can override this by using the <code>syslog:<var>facility</var></code>
1421 syntax where <var>facility</var> can be one of the names usually documented in
1422 syslog(1). The facility is effectively global, and if it is changed
1423 in individual virtual hosts, the final facility specified affects the
1426 <pre class="prettyprint lang-config">ErrorLog syslog:user</pre>
1429 <p>Additional modules can provide their own ErrorLog providers. The syntax
1430 is similar to the <code>syslog</code> example above.</p>
1432 <p>SECURITY: See the <a href="../misc/security_tips.html#serverroot">security tips</a>
1433 document for details on why your security could be compromised
1434 if the directory where log files are stored is writable by
1435 anyone other than the user that starts the server.</p>
1436 <div class="warning"><h3>Note</h3>
1437 <p>When entering a file path on non-Unix platforms, care should be taken
1438 to make sure that only forward slashes are used even though the platform
1439 may allow the use of back slashes. In general it is a good idea to always
1440 use forward slashes throughout the configuration files.</p>
1445 <li><code class="directive"><a href="#loglevel">LogLevel</a></code></li>
1446 <li><a href="../logs.html">Apache HTTP Server Log Files</a></li>
1449 <div class="top"><a href="#page-header"><img alt="top" src="../images/up.gif" /></a></div>
1450 <div class="directive-section"><h2><a name="ErrorLogFormat" id="ErrorLogFormat">ErrorLogFormat</a> <a name="errorlogformat" id="errorlogformat">Directive</a></h2>
1451 <table class="directive">
1452 <tr><th><a href="directive-dict.html#Description">Description:</a></th><td>Format specification for error log entries</td></tr>
1453 <tr><th><a href="directive-dict.html#Syntax">Syntax:</a></th><td><code> ErrorLogFormat [connection|request] <var>format</var></code></td></tr>
1454 <tr><th><a href="directive-dict.html#Context">Context:</a></th><td>server config, virtual host</td></tr>
1455 <tr><th><a href="directive-dict.html#Status">Status:</a></th><td>Core</td></tr>
1456 <tr><th><a href="directive-dict.html#Module">Module:</a></th><td>core</td></tr>
1458 <p><code class="directive">ErrorLogFormat</code> allows to specify what
1459 supplementary information is logged in the error log in addition to the
1460 actual log message.</p>
1462 <pre class="prettyprint lang-config">#Simple example
1463 ErrorLogFormat "[%t] [%l] [pid %P] %F: %E: [client %a] %M"</pre>
1466 <p>Specifying <code>connection</code> or <code>request</code> as first
1467 parameter allows to specify additional formats, causing additional
1468 information to be logged when the first message is logged for a specific
1469 connection or request, respectively. This additional information is only
1470 logged once per connection/request. If a connection or request is processed
1471 without causing any log message, the additional information is not logged
1474 <p>It can happen that some format string items do not produce output. For
1475 example, the Referer header is only present if the log message is
1476 associated to a request and the log message happens at a time when the
1477 Referer header has already been read from the client. If no output is
1478 produced, the default behavior is to delete everything from the preceding
1479 space character to the next space character. This means the log line is
1480 implicitly divided into fields on non-whitespace to whitespace transitions.
1481 If a format string item does not produce output, the whole field is
1482 omitted. For example, if the remote address <code>%a</code> in the log
1483 format <code>[%t] [%l] [%a] %M </code> is not available, the surrounding
1484 brackets are not logged either. Space characters can be escaped with a
1485 backslash to prevent them from delimiting a field. The combination '% '
1486 (percent space) is a zero-width field delimiter that does not produce any
1489 <p>The above behavior can be changed by adding modifiers to the format
1490 string item. A <code>-</code> (minus) modifier causes a minus to be logged if the
1491 respective item does not produce any output. In once-per-connection/request
1492 formats, it is also possible to use the <code>+</code> (plus) modifier. If an
1493 item with the plus modifier does not produce any output, the whole line is
1496 <p>A number as modifier can be used to assign a log severity level to a
1497 format item. The item will only be logged if the severity of the log
1498 message is not higher than the specified log severity level. The number can
1499 range from 1 (alert) over 4 (warn) and 7 (debug) to 15 (trace8).</p>
1501 <p>For example, here's what would happen if you added modifiers to
1502 the <code>%{Referer}i</code> token, which logs the
1503 <code>Referer</code> request header.</p>
1505 <table class="bordered"><tr class="header"><th>Modified Token</th><th>Meaning</th></tr>
1507 <td><code>%-{Referer}i</code></td>
1508 <td>Logs a <code>-</code> if <code>Referer</code> is not set.</td>
1511 <td><code>%+{Referer}i</code></td>
1512 <td>Omits the entire line if <code>Referer</code> is not set.</td>
1515 <td><code>%4{Referer}i</code></td>
1516 <td>Logs the <code>Referer</code> only if the log message severity
1517 is higher than 4.</td>
1521 <p>Some format string items accept additional parameters in braces.</p>
1523 <table class="bordered"><tr class="header"><th>Format String</th> <th>Description</th></tr>
1524 <tr><td><code>%%</code></td>
1525 <td>The percent sign</td></tr>
1526 <tr class="odd"><td><code>%a</code></td>
1527 <td>Client IP address and port of the request</td></tr>
1528 <tr><td><code>%{c}a</code></td>
1529 <td>Underlying peer IP address and port of the connection (see the
1530 <code class="module"><a href="../mod/mod_remoteip.html">mod_remoteip</a></code> module)</td></tr>
1531 <tr class="odd"><td><code>%A</code></td>
1532 <td>Local IP-address and port</td></tr>
1533 <tr><td><code>%{<em>name</em>}e</code></td>
1534 <td>Request environment variable <em>name</em></td></tr>
1535 <tr class="odd"><td><code>%E</code></td>
1536 <td>APR/OS error status code and string</td></tr>
1537 <tr><td><code>%F</code></td>
1538 <td>Source file name and line number of the log call</td></tr>
1539 <tr class="odd"><td><code>%{<em>name</em>}i</code></td>
1540 <td>Request header <em>name</em></td></tr>
1541 <tr><td><code>%k</code></td>
1542 <td>Number of keep-alive requests on this connection</td></tr>
1543 <tr class="odd"><td><code>%l</code></td>
1544 <td>Loglevel of the message</td></tr>
1545 <tr><td><code>%L</code></td>
1546 <td>Log ID of the request</td></tr>
1547 <tr class="odd"><td><code>%{c}L</code></td>
1548 <td>Log ID of the connection</td></tr>
1549 <tr><td><code>%{C}L</code></td>
1550 <td>Log ID of the connection if used in connection scope, empty otherwise</td></tr>
1551 <tr class="odd"><td><code>%m</code></td>
1552 <td>Name of the module logging the message</td></tr>
1553 <tr><td><code>%M</code></td>
1554 <td>The actual log message</td></tr>
1555 <tr class="odd"><td><code>%{<em>name</em>}n</code></td>
1556 <td>Request note <em>name</em></td></tr>
1557 <tr><td><code>%P</code></td>
1558 <td>Process ID of current process</td></tr>
1559 <tr class="odd"><td><code>%T</code></td>
1560 <td>Thread ID of current thread</td></tr>
1561 <tr><td><code>%{g}T</code></td>
1562 <td>System unique thread ID of current thread (the same ID as
1563 displayed by e.g. <code>top</code>; currently Linux only)</td></tr>
1564 <tr class="odd"><td><code>%t</code></td>
1565 <td>The current time</td></tr>
1566 <tr><td><code>%{u}t</code></td>
1567 <td>The current time including micro-seconds</td></tr>
1568 <tr class="odd"><td><code>%{cu}t</code></td>
1569 <td>The current time in compact ISO 8601 format, including
1570 micro-seconds</td></tr>
1571 <tr><td><code>%v</code></td>
1572 <td>The canonical <code class="directive"><a href="#servername">ServerName</a></code>
1573 of the current server.</td></tr>
1574 <tr class="odd"><td><code>%V</code></td>
1575 <td>The server name of the server serving the request according to the
1576 <code class="directive"><a href="#usecanonicalname">UseCanonicalName</a></code>
1578 <tr><td><code>\ </code> (backslash space)</td>
1579 <td>Non-field delimiting space</td></tr>
1580 <tr class="odd"><td><code>% </code> (percent space)</td>
1581 <td>Field delimiter (no output)</td></tr>
1584 <p>The log ID format <code>%L</code> produces a unique id for a connection
1585 or request. This can be used to correlate which log lines belong to the
1586 same connection or request, which request happens on which connection.
1587 A <code>%L</code> format string is also available in
1588 <code class="module"><a href="../mod/mod_log_config.html">mod_log_config</a></code> to allow to correlate access log entries
1589 with error log lines. If <code class="module"><a href="../mod/mod_unique_id.html">mod_unique_id</a></code> is loaded, its
1590 unique id will be used as log ID for requests.</p>
1592 <pre class="prettyprint lang-config">#Example (default format for threaded MPMs)
1593 ErrorLogFormat "[%{u}t] [%-m:%l] [pid %P:tid %T] %7F: %E: [client\ %a] %M% ,\ referer\ %{Referer}i"</pre>
1596 <p>This would result in error messages such as:</p>
1598 <div class="example"><p><code>
1599 [Thu May 12 08:28:57.652118 2011] [core:error] [pid 8777:tid 4326490112] [client ::1:58619] File does not exist: /usr/local/apache2/htdocs/favicon.ico
1602 <p>Notice that, as discussed above, some fields are omitted
1603 entirely because they are not defined.</p>
1605 <pre class="prettyprint lang-config">#Example (similar to the 2.2.x format)
1606 ErrorLogFormat "[%t] [%l] %7F: %E: [client\ %a] %M% ,\ referer\ %{Referer}i"</pre>
1609 <pre class="prettyprint lang-config">#Advanced example with request/connection log IDs
1610 ErrorLogFormat "[%{uc}t] [%-m:%-l] [R:%L] [C:%{C}L] %7F: %E: %M"
1611 ErrorLogFormat request "[%{uc}t] [R:%L] Request %k on C:%{c}L pid:%P tid:%T"
1612 ErrorLogFormat request "[%{uc}t] [R:%L] UA:'%+{User-Agent}i'"
1613 ErrorLogFormat request "[%{uc}t] [R:%L] Referer:'%+{Referer}i'"
1614 ErrorLogFormat connection "[%{uc}t] [C:%{c}L] local\ %a remote\ %A"</pre>
1620 <li><code class="directive"><a href="#errorlog">ErrorLog</a></code></li>
1621 <li><code class="directive"><a href="#loglevel">LogLevel</a></code></li>
1622 <li><a href="../logs.html">Apache HTTP Server Log Files</a></li>
1625 <div class="top"><a href="#page-header"><img alt="top" src="../images/up.gif" /></a></div>
1626 <div class="directive-section"><h2><a name="ExtendedStatus" id="ExtendedStatus">ExtendedStatus</a> <a name="extendedstatus" id="extendedstatus">Directive</a></h2>
1627 <table class="directive">
1628 <tr><th><a href="directive-dict.html#Description">Description:</a></th><td>Keep track of extended status information for each
1630 <tr><th><a href="directive-dict.html#Syntax">Syntax:</a></th><td><code>ExtendedStatus On|Off</code></td></tr>
1631 <tr><th><a href="directive-dict.html#Default">Default:</a></th><td><code>ExtendedStatus Off[*]</code></td></tr>
1632 <tr><th><a href="directive-dict.html#Context">Context:</a></th><td>server config</td></tr>
1633 <tr><th><a href="directive-dict.html#Status">Status:</a></th><td>Core</td></tr>
1634 <tr><th><a href="directive-dict.html#Module">Module:</a></th><td>core</td></tr>
1636 <p>This option tracks additional data per worker about the
1637 currently executing request and creates a utilization summary.
1638 You can see these variables during runtime by configuring
1639 <code class="module"><a href="../mod/mod_status.html">mod_status</a></code>. Note that other modules may
1640 rely on this scoreboard.</p>
1642 <p>This setting applies to the entire server and cannot be
1643 enabled or disabled on a virtualhost-by-virtualhost basis.
1644 The collection of extended status information can slow down
1645 the server. Also note that this setting cannot be changed
1646 during a graceful restart.</p>
1649 <p>Note that loading <code class="module"><a href="../mod/mod_status.html">mod_status</a></code> will change
1650 the default behavior to ExtendedStatus On, while other
1651 third party modules may do the same. Such modules rely on
1652 collecting detailed information about the state of all workers.
1653 The default is changed by <code class="module"><a href="../mod/mod_status.html">mod_status</a></code> beginning
1654 with version 2.3.6. The previous default was always Off.</p>
1659 <div class="top"><a href="#page-header"><img alt="top" src="../images/up.gif" /></a></div>
1660 <div class="directive-section"><h2><a name="FileETag" id="FileETag">FileETag</a> <a name="fileetag" id="fileetag">Directive</a></h2>
1661 <table class="directive">
1662 <tr><th><a href="directive-dict.html#Description">Description:</a></th><td>File attributes used to create the ETag
1663 HTTP response header for static files</td></tr>
1664 <tr><th><a href="directive-dict.html#Syntax">Syntax:</a></th><td><code>FileETag <var>component</var> ...</code></td></tr>
1665 <tr><th><a href="directive-dict.html#Default">Default:</a></th><td><code>FileETag MTime Size</code></td></tr>
1666 <tr><th><a href="directive-dict.html#Context">Context:</a></th><td>server config, virtual host, directory, .htaccess</td></tr>
1667 <tr><th><a href="directive-dict.html#Override">Override:</a></th><td>FileInfo</td></tr>
1668 <tr><th><a href="directive-dict.html#Status">Status:</a></th><td>Core</td></tr>
1669 <tr><th><a href="directive-dict.html#Module">Module:</a></th><td>core</td></tr>
1670 <tr><th><a href="directive-dict.html#Compatibility">Compatibility:</a></th><td>The default used to be "INode MTime Size" in 2.3.14 and
1674 The <code class="directive">FileETag</code> directive configures the file
1675 attributes that are used to create the <code>ETag</code> (entity
1676 tag) response header field when the document is based on a static file.
1677 (The <code>ETag</code> value is used in cache management to save
1678 network bandwidth.) The
1679 <code class="directive">FileETag</code> directive allows you to choose
1680 which of these -- if any -- should be used. The recognized keywords are:
1684 <dt><strong>INode</strong></dt>
1685 <dd>The file's i-node number will be included in the calculation</dd>
1686 <dt><strong>MTime</strong></dt>
1687 <dd>The date and time the file was last modified will be included</dd>
1688 <dt><strong>Size</strong></dt>
1689 <dd>The number of bytes in the file will be included</dd>
1690 <dt><strong>All</strong></dt>
1691 <dd>All available fields will be used. This is equivalent to:
1692 <pre class="prettyprint lang-config">FileETag INode MTime Size</pre>
1694 <dt><strong>None</strong></dt>
1695 <dd>If a document is file-based, no <code>ETag</code> field will be
1696 included in the response</dd>
1699 <p>The <code>INode</code>, <code>MTime</code>, and <code>Size</code>
1700 keywords may be prefixed with either <code>+</code> or <code>-</code>,
1701 which allow changes to be made to the default setting inherited
1702 from a broader scope. Any keyword appearing without such a prefix
1703 immediately and completely cancels the inherited setting.</p>
1705 <p>If a directory's configuration includes
1706 <code>FileETag INode MTime Size</code>, and a
1707 subdirectory's includes <code>FileETag -INode</code>,
1708 the setting for that subdirectory (which will be inherited by
1709 any sub-subdirectories that don't override it) will be equivalent to
1710 <code>FileETag MTime Size</code>.</p>
1711 <div class="warning"><h3>Warning</h3>
1712 Do not change the default for directories or locations that have WebDAV
1713 enabled and use <code class="module"><a href="../mod/mod_dav_fs.html">mod_dav_fs</a></code> as a storage provider.
1714 <code class="module"><a href="../mod/mod_dav_fs.html">mod_dav_fs</a></code> uses <code>MTime Size</code>
1715 as a fixed format for <code>ETag</code> comparisons on conditional requests.
1716 These conditional requests will break if the <code>ETag</code> format is
1717 changed via <code class="directive">FileETag</code>.
1719 <div class="note"><h3>Server Side Includes</h3>
1720 An ETag is not generated for responses parsed by <code class="module"><a href="../mod/mod_include.html">mod_include</a></code>
1721 since the response entity can change without a change of the INode, MTime, or Size
1722 of the static file with embedded SSI directives.
1727 <div class="top"><a href="#page-header"><img alt="top" src="../images/up.gif" /></a></div>
1728 <div class="directive-section"><h2><a name="Files" id="Files"><Files></a> <a name="files" id="files">Directive</a></h2>
1729 <table class="directive">
1730 <tr><th><a href="directive-dict.html#Description">Description:</a></th><td>Contains directives that apply to matched
1732 <tr><th><a href="directive-dict.html#Syntax">Syntax:</a></th><td><code><Files <var>filename</var>> ... </Files></code></td></tr>
1733 <tr><th><a href="directive-dict.html#Context">Context:</a></th><td>server config, virtual host, directory, .htaccess</td></tr>
1734 <tr><th><a href="directive-dict.html#Override">Override:</a></th><td>All</td></tr>
1735 <tr><th><a href="directive-dict.html#Status">Status:</a></th><td>Core</td></tr>
1736 <tr><th><a href="directive-dict.html#Module">Module:</a></th><td>core</td></tr>
1738 <p>The <code class="directive"><Files></code> directive
1739 limits the scope of the enclosed directives by filename. It is comparable
1740 to the <code class="directive"><a href="#directory"><Directory></a></code>
1741 and <code class="directive"><a href="#location"><Location></a></code>
1742 directives. It should be matched with a <code></Files></code>
1743 directive. The directives given within this section will be applied to
1744 any object with a basename (last component of filename) matching the
1745 specified filename. <code class="directive"><Files></code>
1746 sections are processed in the order they appear in the
1747 configuration file, after the <code class="directive"><a href="#directory"><Directory></a></code> sections and
1748 <code>.htaccess</code> files are read, but before <code class="directive"><a href="#location"><Location></a></code> sections. Note
1749 that <code class="directive"><Files></code> can be nested
1750 inside <code class="directive"><a href="#directory"><Directory></a></code> sections to restrict the
1751 portion of the filesystem they apply to.</p>
1753 <p>The <var>filename</var> argument should include a filename, or
1754 a wild-card string, where <code>?</code> matches any single character,
1755 and <code>*</code> matches any sequences of characters.</p>
1756 <pre class="prettyprint lang-config"><Files "cat.html">
1757 # Insert stuff that applies to cat.html here
1760 <Files "?at.*">
1761 # This would apply to cat.html, bat.html, hat.php and so on.
1762 </Files></pre>
1764 <p><a class="glossarylink" href="../glossary.html#regex" title="see glossary">Regular expressions</a>
1765 can also be used, with the addition of the
1766 <code>~</code> character. For example:</p>
1768 <pre class="prettyprint lang-config"><Files ~ "\.(gif|jpe?g|png)$">
1770 </Files></pre>
1773 <p>would match most common Internet graphics formats. <code class="directive"><a href="#filesmatch"><FilesMatch></a></code> is preferred,
1776 <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
1777 <code>.htaccess</code> files. This allows users to control access to
1778 their own files, at a file-by-file level.</p>
1783 <li><a href="../sections.html">How <Directory>, <Location>
1784 and <Files> sections work</a> for an explanation of how these
1785 different sections are combined when a request is received</li>
1788 <div class="top"><a href="#page-header"><img alt="top" src="../images/up.gif" /></a></div>
1789 <div class="directive-section"><h2><a name="FilesMatch" id="FilesMatch"><FilesMatch></a> <a name="filesmatch" id="filesmatch">Directive</a></h2>
1790 <table class="directive">
1791 <tr><th><a href="directive-dict.html#Description">Description:</a></th><td>Contains directives that apply to regular-expression matched
1793 <tr><th><a href="directive-dict.html#Syntax">Syntax:</a></th><td><code><FilesMatch <var>regex</var>> ... </FilesMatch></code></td></tr>
1794 <tr><th><a href="directive-dict.html#Context">Context:</a></th><td>server config, virtual host, directory, .htaccess</td></tr>
1795 <tr><th><a href="directive-dict.html#Override">Override:</a></th><td>All</td></tr>
1796 <tr><th><a href="directive-dict.html#Status">Status:</a></th><td>Core</td></tr>
1797 <tr><th><a href="directive-dict.html#Module">Module:</a></th><td>core</td></tr>
1799 <p>The <code class="directive"><FilesMatch></code> directive
1800 limits the scope of the enclosed directives by filename, just as the
1801 <code class="directive"><a href="#files"><Files></a></code> directive
1802 does. However, it accepts a <a class="glossarylink" href="../glossary.html#regex" title="see glossary">regular
1803 expression</a>. For example:</p>
1805 <pre class="prettyprint lang-config"><FilesMatch ".+\.(gif|jpe?g|png)$">
1807 </FilesMatch></pre>
1810 <p>would match most common Internet graphics formats.</p>
1812 <div class="note">The <code>.+</code> at the start of the regex ensures that
1813 files named <code>.png</code>, or <code>.gif</code>, for example,
1814 are not matched.</div>
1816 <p>From 2.4.8 onwards, named groups and backreferences are captured and
1817 written to the environment with the corresponding name prefixed with
1818 "MATCH_" and in upper case. This allows elements of files to be referenced
1819 from within <a href="../expr.html">expressions</a> and modules like
1820 <code class="module"><a href="../mod/mod_rewrite.html">mod_rewrite</a></code>. In order to prevent confusion, numbered
1821 (unnamed) backreferences are ignored. Use named groups instead.</p>
1823 <pre class="prettyprint lang-config"><FilesMatch "^(?<sitename>[^/]+)">
1824 require ldap-group cn=%{env:MATCH_SITENAME},ou=combined,o=Example
1825 </FilesMatch></pre>
1830 <li><a href="../sections.html">How <Directory>, <Location>
1831 and <Files> sections work</a> for an explanation of how these
1832 different sections are combined when a request is received</li>
1835 <div class="top"><a href="#page-header"><img alt="top" src="../images/up.gif" /></a></div>
1836 <div class="directive-section"><h2><a name="ForceType" id="ForceType">ForceType</a> <a name="forcetype" id="forcetype">Directive</a></h2>
1837 <table class="directive">
1838 <tr><th><a href="directive-dict.html#Description">Description:</a></th><td>Forces all matching files to be served with the specified
1839 media type in the HTTP Content-Type header field</td></tr>
1840 <tr><th><a href="directive-dict.html#Syntax">Syntax:</a></th><td><code>ForceType <var>media-type</var>|None</code></td></tr>
1841 <tr><th><a href="directive-dict.html#Context">Context:</a></th><td>directory, .htaccess</td></tr>
1842 <tr><th><a href="directive-dict.html#Override">Override:</a></th><td>FileInfo</td></tr>
1843 <tr><th><a href="directive-dict.html#Status">Status:</a></th><td>Core</td></tr>
1844 <tr><th><a href="directive-dict.html#Module">Module:</a></th><td>core</td></tr>
1846 <p>When placed into an <code>.htaccess</code> file or a
1847 <code class="directive"><a href="#directory"><Directory></a></code>, or
1848 <code class="directive"><a href="#location"><Location></a></code> or
1849 <code class="directive"><a href="#files"><Files></a></code>
1850 section, this directive forces all matching files to be served
1851 with the content type identification given by
1852 <var>media-type</var>. For example, if you had a directory full of
1853 GIF files, but did not want to label them all with <code>.gif</code>,
1854 you might want to use:</p>
1856 <pre class="prettyprint lang-config">ForceType image/gif</pre>
1859 <p>Note that this directive overrides other indirect media type
1860 associations defined in mime.types or via the
1861 <code class="directive"><a href="../mod/mod_mime.html#addtype">AddType</a></code>.</p>
1863 <p>You can also override more general
1864 <code class="directive">ForceType</code> settings
1865 by using the value of <code>None</code>:</p>
1867 <pre class="prettyprint lang-config"># force all files to be image/gif:
1868 <Location "/images">
1872 # but normal mime-type associations here:
1873 <Location "/images/mixed">
1875 </Location></pre>
1878 <p>This directive primarily overrides the content types generated for
1879 static files served out of the filesystem. For resources other than
1880 static files, where the generator of the response typically specifies
1881 a Content-Type, this directive has no effect.</p>
1884 <div class="note"><h3>Note</h3>
1885 <p>If no handler is explicitly set for a request, the specified content
1886 type will also be used as the handler name. </p>
1888 <p>When explicit directives such as
1889 <code class="directive"><a href="#sethandler">SetHandler</a></code> or
1890 <code class="directive"><a href="../mod/mod_mime.html#addhandler">AddHandler</a></code> do not apply
1891 to the current request, the internal handler name normally set by those
1892 directives is instead set to the content type specified by this directive.
1895 This is a historical behavior that some third-party modules
1896 (such as mod_php) may look for a "synthetic" content type used only to
1897 signal the module to take responsibility for the matching request.
1900 <p>Configurations that rely on such "synthetic" types should be avoided.
1901 Additionally, configurations that restrict access to
1902 <code class="directive"><a href="#sethandler">SetHandler</a></code> or
1903 <code class="directive"><a href="../mod/mod_mime.html#addhandler">AddHandler</a></code> should
1904 restrict access to this directive as well.</p>
1909 <div class="top"><a href="#page-header"><img alt="top" src="../images/up.gif" /></a></div>
1910 <div class="directive-section"><h2><a name="GprofDir" id="GprofDir">GprofDir</a> <a name="gprofdir" id="gprofdir">Directive</a></h2>
1911 <table class="directive">
1912 <tr><th><a href="directive-dict.html#Description">Description:</a></th><td>Directory to write gmon.out profiling data to. </td></tr>
1913 <tr><th><a href="directive-dict.html#Syntax">Syntax:</a></th><td><code>GprofDir <var>/tmp/gprof/</var>|<var>/tmp/gprof/</var>%</code></td></tr>
1914 <tr><th><a href="directive-dict.html#Context">Context:</a></th><td>server config, virtual host</td></tr>
1915 <tr><th><a href="directive-dict.html#Status">Status:</a></th><td>Core</td></tr>
1916 <tr><th><a href="directive-dict.html#Module">Module:</a></th><td>core</td></tr>
1918 <p>When the server has been compiled with gprof profiling support,
1919 <code class="directive">GprofDir</code> causes <code>gmon.out</code> files to
1920 be written to the specified directory when the process exits. If the
1921 argument ends with a percent symbol ('%'), subdirectories are created
1922 for each process id.</p>
1924 <p>This directive currently only works with the <code class="module"><a href="../mod/prefork.html">prefork</a></code>
1928 <div class="top"><a href="#page-header"><img alt="top" src="../images/up.gif" /></a></div>
1929 <div class="directive-section"><h2><a name="HostnameLookups" id="HostnameLookups">HostnameLookups</a> <a name="hostnamelookups" id="hostnamelookups">Directive</a></h2>
1930 <table class="directive">
1931 <tr><th><a href="directive-dict.html#Description">Description:</a></th><td>Enables DNS lookups on client IP addresses</td></tr>
1932 <tr><th><a href="directive-dict.html#Syntax">Syntax:</a></th><td><code>HostnameLookups On|Off|Double</code></td></tr>
1933 <tr><th><a href="directive-dict.html#Default">Default:</a></th><td><code>HostnameLookups Off</code></td></tr>
1934 <tr><th><a href="directive-dict.html#Context">Context:</a></th><td>server config, virtual host, directory</td></tr>
1935 <tr><th><a href="directive-dict.html#Status">Status:</a></th><td>Core</td></tr>
1936 <tr><th><a href="directive-dict.html#Module">Module:</a></th><td>core</td></tr>
1938 <p>This directive enables DNS lookups so that host names can be
1939 logged (and passed to CGIs/SSIs in <code>REMOTE_HOST</code>).
1940 The value <code>Double</code> refers to doing double-reverse
1941 DNS lookup. That is, after a reverse lookup is performed, a forward
1942 lookup is then performed on that result. At least one of the IP
1943 addresses in the forward lookup must match the original
1944 address. (In "tcpwrappers" terminology this is called
1945 <code>PARANOID</code>.)</p>
1947 <p>Regardless of the setting, when <code class="module"><a href="../mod/mod_authz_host.html">mod_authz_host</a></code> is
1948 used for controlling access by hostname, a double reverse lookup
1949 will be performed. This is necessary for security. Note that the
1950 result of this double-reverse isn't generally available unless you
1951 set <code>HostnameLookups Double</code>. For example, if only
1952 <code>HostnameLookups On</code> and a request is made to an object
1953 that is protected by hostname restrictions, regardless of whether
1954 the double-reverse fails or not, CGIs will still be passed the
1955 single-reverse result in <code>REMOTE_HOST</code>.</p>
1957 <p>The default is <code>Off</code> in order to save the network
1958 traffic for those sites that don't truly need the reverse
1959 lookups done. It is also better for the end users because they
1960 don't have to suffer the extra latency that a lookup entails.
1961 Heavily loaded sites should leave this directive
1962 <code>Off</code>, since DNS lookups can take considerable
1963 amounts of time. The utility <code class="program"><a href="../programs/logresolve.html">logresolve</a></code>, compiled by
1964 default to the <code>bin</code> subdirectory of your installation
1965 directory, can be used to look up host names from logged IP addresses
1968 <p>Finally, if you have <a href="mod_authz_host.html#reqhost">hostname-based Require
1969 directives</a>, a hostname lookup will be performed regardless of
1970 the setting of <code>HostnameLookups</code>.</p>
1973 <div class="top"><a href="#page-header"><img alt="top" src="../images/up.gif" /></a></div>
1974 <div class="directive-section"><h2><a name="If" id="If"><If></a> <a name="if" id="if">Directive</a></h2>
1975 <table class="directive">
1976 <tr><th><a href="directive-dict.html#Description">Description:</a></th><td>Contains directives that apply only if a condition is
1977 satisfied by a request at runtime</td></tr>
1978 <tr><th><a href="directive-dict.html#Syntax">Syntax:</a></th><td><code><If <var>expression</var>> ... </If></code></td></tr>
1979 <tr><th><a href="directive-dict.html#Context">Context:</a></th><td>server config, virtual host, directory, .htaccess</td></tr>
1980 <tr><th><a href="directive-dict.html#Override">Override:</a></th><td>All</td></tr>
1981 <tr><th><a href="directive-dict.html#Status">Status:</a></th><td>Core</td></tr>
1982 <tr><th><a href="directive-dict.html#Module">Module:</a></th><td>core</td></tr>
1984 <p>The <code class="directive"><If></code> directive
1985 evaluates an expression at runtime, and applies the enclosed
1986 directives if and only if the expression evaluates to true.
1989 <pre class="prettyprint lang-config"><If "-z req('Host')"></pre>
1992 <p>would match HTTP/1.0 requests without a <var>Host:</var> header.
1993 Expressions may contain various shell-like operators for string
1994 comparison (<code>==</code>, <code>!=</code>, <code><</code>, ...),
1995 integer comparison (<code>-eq</code>, <code>-ne</code>, ...),
1996 and others (<code>-n</code>, <code>-z</code>, <code>-f</code>, ...).
1997 It is also possible to use regular expressions, </p>
1999 <pre class="prettyprint lang-config"><If "%{QUERY_STRING} =~ /(delete|commit)=.*?elem/"></pre>
2002 <p>shell-like pattern matches and many other operations. These operations
2003 can be done on request headers (<code>req</code>), environment variables
2004 (<code>env</code>), and a large number of other properties. The full
2005 documentation is available in <a href="../expr.html">Expressions in
2006 Apache HTTP Server</a>.</p>
2008 <p>Only directives that support the <a href="directive-dict.html#Context">directory context</a> can be used within this configuration section.</p>
2010 <div class="warning">
2011 Certain variables, such as <code>CONTENT_TYPE</code> and other
2012 response headers, are set after <If> conditions have already
2013 been evaluated, and so will not be available to use in this
2020 <li><a href="../expr.html">Expressions in Apache HTTP Server</a>,
2021 for a complete reference and more examples.</li>
2022 <li><code class="directive"><a href="#elseif"><ElseIf></a></code></li>
2023 <li><code class="directive"><a href="#else"><Else></a></code></li>
2024 <li><a href="../sections.html">How <Directory>, <Location>,
2025 <Files> sections work</a> for an explanation of how these
2026 different sections are combined when a request is received.
2027 <code class="directive"><If></code>,
2028 <code class="directive"><ElseIf></code>, and
2029 <code class="directive"><Else></code> are applied last.</li>
2032 <div class="top"><a href="#page-header"><img alt="top" src="../images/up.gif" /></a></div>
2033 <div class="directive-section"><h2><a name="IfDefine" id="IfDefine"><IfDefine></a> <a name="ifdefine" id="ifdefine">Directive</a></h2>
2034 <table class="directive">
2035 <tr><th><a href="directive-dict.html#Description">Description:</a></th><td>Encloses directives that will be processed only
2036 if a test is true at startup</td></tr>
2037 <tr><th><a href="directive-dict.html#Syntax">Syntax:</a></th><td><code><IfDefine [!]<var>parameter-name</var>> ...
2038 </IfDefine></code></td></tr>
2039 <tr><th><a href="directive-dict.html#Context">Context:</a></th><td>server config, virtual host, directory, .htaccess</td></tr>
2040 <tr><th><a href="directive-dict.html#Override">Override:</a></th><td>All</td></tr>
2041 <tr><th><a href="directive-dict.html#Status">Status:</a></th><td>Core</td></tr>
2042 <tr><th><a href="directive-dict.html#Module">Module:</a></th><td>core</td></tr>
2044 <p>The <code><IfDefine <var>test</var>>...</IfDefine>
2045 </code> section is used to mark directives that are conditional. The
2046 directives within an <code class="directive"><IfDefine></code>
2047 section are only processed if the <var>test</var> is true. If <var>
2048 test</var> is false, everything between the start and end markers is
2051 <p>The <var>test</var> in the <code class="directive"><IfDefine></code> section directive can be one of two forms:</p>
2054 <li><var>parameter-name</var></li>
2056 <li><code>!</code><var>parameter-name</var></li>
2059 <p>In the former case, the directives between the start and end
2060 markers are only processed if the parameter named
2061 <var>parameter-name</var> is defined. The second format reverses
2062 the test, and only processes the directives if
2063 <var>parameter-name</var> is <strong>not</strong> defined.</p>
2065 <p>The <var>parameter-name</var> argument is a define as given on the
2066 <code class="program"><a href="../programs/httpd.html">httpd</a></code> command line via <code>-D<var>parameter</var>
2067 </code> at the time the server was started or by the <code class="directive"><a href="#define">Define</a></code> directive.</p>
2069 <p><code class="directive"><IfDefine></code> sections are
2070 nest-able, which can be used to implement simple
2071 multiple-parameter tests. Example:</p>
2073 <div class="example"><p><code>httpd -DReverseProxy -DUseCache -DMemCache ...</code></p></div>
2074 <pre class="prettyprint lang-config"><IfDefine ReverseProxy>
2075 LoadModule proxy_module modules/mod_proxy.so
2076 LoadModule proxy_http_module modules/mod_proxy_http.so
2077 <IfDefine UseCache>
2078 LoadModule cache_module modules/mod_cache.so
2079 <IfDefine MemCache>
2080 LoadModule mem_cache_module modules/mod_mem_cache.so
2082 <IfDefine !MemCache>
2083 LoadModule cache_disk_module modules/mod_cache_disk.so
2086 </IfDefine></pre>
2090 <div class="top"><a href="#page-header"><img alt="top" src="../images/up.gif" /></a></div>
2091 <div class="directive-section"><h2><a name="IfModule" id="IfModule"><IfModule></a> <a name="ifmodule" id="ifmodule">Directive</a></h2>
2092 <table class="directive">
2093 <tr><th><a href="directive-dict.html#Description">Description:</a></th><td>Encloses directives that are processed conditional on the
2094 presence or absence of a specific module</td></tr>
2095 <tr><th><a href="directive-dict.html#Syntax">Syntax:</a></th><td><code><IfModule [!]<var>module-file</var>|<var>module-identifier</var>> ...
2096 </IfModule></code></td></tr>
2097 <tr><th><a href="directive-dict.html#Context">Context:</a></th><td>server config, virtual host, directory, .htaccess</td></tr>
2098 <tr><th><a href="directive-dict.html#Override">Override:</a></th><td>All</td></tr>
2099 <tr><th><a href="directive-dict.html#Status">Status:</a></th><td>Core</td></tr>
2100 <tr><th><a href="directive-dict.html#Module">Module:</a></th><td>core</td></tr>
2102 <p>The <code><IfModule <var>test</var>>...</IfModule></code>
2103 section is used to mark directives that are conditional on the presence of
2104 a specific module. The directives within an <code class="directive"><IfModule></code> section are only processed if the <var>test</var>
2105 is true. If <var>test</var> is false, everything between the start and
2106 end markers is ignored.</p>
2108 <p>The <var>test</var> in the <code class="directive"><IfModule></code> section directive can be one of two forms:</p>
2111 <li><var>module</var></li>
2113 <li>!<var>module</var></li>
2116 <p>In the former case, the directives between the start and end
2117 markers are only processed if the module named <var>module</var>
2118 is included in Apache httpd -- either compiled in or
2119 dynamically loaded using <code class="directive"><a href="../mod/mod_so.html#loadmodule">LoadModule</a></code>. The second format reverses the test,
2120 and only processes the directives if <var>module</var> is
2121 <strong>not</strong> included.</p>
2123 <p>The <var>module</var> argument can be either the module identifier or
2124 the file name of the module, at the time it was compiled. For example,
2125 <code>rewrite_module</code> is the identifier and
2126 <code>mod_rewrite.c</code> is the file name. If a module consists of
2127 several source files, use the name of the file containing the string
2128 <code>STANDARD20_MODULE_STUFF</code>.</p>
2130 <p><code class="directive"><IfModule></code> sections are
2131 nest-able, which can be used to implement simple multiple-module
2134 <div class="note">This section should only be used if you need to have one
2135 configuration file that works whether or not a specific module
2136 is available. In normal operation, directives need not be
2137 placed in <code class="directive"><IfModule></code>
2141 <div class="top"><a href="#page-header"><img alt="top" src="../images/up.gif" /></a></div>
2142 <div class="directive-section"><h2><a name="Include" id="Include">Include</a> <a name="include" id="include">Directive</a></h2>
2143 <table class="directive">
2144 <tr><th><a href="directive-dict.html#Description">Description:</a></th><td>Includes other configuration files from within
2145 the server configuration files</td></tr>
2146 <tr><th><a href="directive-dict.html#Syntax">Syntax:</a></th><td><code>Include <var>file-path</var>|<var>directory-path</var>|<var>wildcard</var></code></td></tr>
2147 <tr><th><a href="directive-dict.html#Context">Context:</a></th><td>server config, virtual host, directory</td></tr>
2148 <tr><th><a href="directive-dict.html#Status">Status:</a></th><td>Core</td></tr>
2149 <tr><th><a href="directive-dict.html#Module">Module:</a></th><td>core</td></tr>
2150 <tr><th><a href="directive-dict.html#Compatibility">Compatibility:</a></th><td>Directory
2151 wildcard matching available in 2.3.6 and later</td></tr>
2153 <p>This directive allows inclusion of other configuration files
2154 from within the server configuration files.</p>
2156 <p>Shell-style (<code>fnmatch()</code>) wildcard characters can be used
2157 in the filename or directory parts of the path to include several files
2158 at once, in alphabetical order. In addition, if
2159 <code class="directive">Include</code> points to a directory, rather than a file,
2160 Apache httpd will read all files in that directory and any subdirectory.
2161 However, including entire directories is not recommended, because it is
2162 easy to accidentally leave temporary files in a directory that can cause
2163 <code class="program"><a href="../programs/httpd.html">httpd</a></code> to fail. Instead, we encourage you to use the
2164 wildcard syntax shown below, to include files that match a particular
2165 pattern, such as *.conf, for example.</p>
2167 <p>The <code class="directive"><a href="#include">Include</a></code> directive will
2168 <strong>fail with an error</strong> if a wildcard expression does not
2169 match any file. The <code class="directive"><a href="#includeoptional">IncludeOptional</a></code>
2170 directive can be used if non-matching wildcards should be ignored.</p>
2172 <p>The file path specified may be an absolute path, or may be relative
2173 to the <code class="directive"><a href="#serverroot">ServerRoot</a></code> directory.</p>
2177 <pre class="prettyprint lang-config">Include /usr/local/apache2/conf/ssl.conf
2178 Include /usr/local/apache2/conf/vhosts/*.conf</pre>
2181 <p>Or, providing paths relative to your <code class="directive"><a href="#serverroot">ServerRoot</a></code> directory:</p>
2183 <pre class="prettyprint lang-config">Include conf/ssl.conf
2184 Include conf/vhosts/*.conf</pre>
2187 <p>Wildcards may be included in the directory or file portion of the
2188 path. This example will fail if there is no subdirectory in conf/vhosts
2189 that contains at least one *.conf file:</p>
2191 <pre class="prettyprint lang-config">Include conf/vhosts/*/*.conf</pre>
2194 <p>Alternatively, the following command will just be ignored in case of
2195 missing files or directories:</p>
2197 <pre class="prettyprint lang-config">IncludeOptional conf/vhosts/*/*.conf</pre>
2203 <li><code class="directive"><a href="#includeoptional">IncludeOptional</a></code></li>
2204 <li><code class="program"><a href="../programs/apachectl.html">apachectl</a></code></li>
2207 <div class="top"><a href="#page-header"><img alt="top" src="../images/up.gif" /></a></div>
2208 <div class="directive-section"><h2><a name="IncludeOptional" id="IncludeOptional">IncludeOptional</a> <a name="includeoptional" id="includeoptional">Directive</a></h2>
2209 <table class="directive">
2210 <tr><th><a href="directive-dict.html#Description">Description:</a></th><td>Includes other configuration files from within
2211 the server configuration files</td></tr>
2212 <tr><th><a href="directive-dict.html#Syntax">Syntax:</a></th><td><code>IncludeOptional <var>file-path</var>|<var>directory-path</var>|<var>wildcard</var></code></td></tr>
2213 <tr><th><a href="directive-dict.html#Context">Context:</a></th><td>server config, virtual host, directory</td></tr>
2214 <tr><th><a href="directive-dict.html#Status">Status:</a></th><td>Core</td></tr>
2215 <tr><th><a href="directive-dict.html#Module">Module:</a></th><td>core</td></tr>
2216 <tr><th><a href="directive-dict.html#Compatibility">Compatibility:</a></th><td>Available in 2.3.6 and later</td></tr>
2218 <p>This directive allows inclusion of other configuration files
2219 from within the server configuration files. It works identically to the
2220 <code class="directive"><a href="#include">Include</a></code> directive, with the
2221 exception that if wildcards do not match any file or directory, the
2222 <code class="directive"><a href="#includeoptional">IncludeOptional</a></code> directive will be
2223 silently ignored instead of causing an error.</p>
2227 <li><code class="directive"><a href="#include">Include</a></code></li>
2228 <li><code class="program"><a href="../programs/apachectl.html">apachectl</a></code></li>
2231 <div class="top"><a href="#page-header"><img alt="top" src="../images/up.gif" /></a></div>
2232 <div class="directive-section"><h2><a name="KeepAlive" id="KeepAlive">KeepAlive</a> <a name="keepalive" id="keepalive">Directive</a></h2>
2233 <table class="directive">
2234 <tr><th><a href="directive-dict.html#Description">Description:</a></th><td>Enables HTTP persistent connections</td></tr>
2235 <tr><th><a href="directive-dict.html#Syntax">Syntax:</a></th><td><code>KeepAlive On|Off</code></td></tr>
2236 <tr><th><a href="directive-dict.html#Default">Default:</a></th><td><code>KeepAlive On</code></td></tr>
2237 <tr><th><a href="directive-dict.html#Context">Context:</a></th><td>server config, virtual host</td></tr>
2238 <tr><th><a href="directive-dict.html#Status">Status:</a></th><td>Core</td></tr>
2239 <tr><th><a href="directive-dict.html#Module">Module:</a></th><td>core</td></tr>
2241 <p>The Keep-Alive extension to HTTP/1.0 and the persistent
2242 connection feature of HTTP/1.1 provide long-lived HTTP sessions
2243 which allow multiple requests to be sent over the same TCP
2244 connection. In some cases this has been shown to result in an
2245 almost 50% speedup in latency times for HTML documents with
2246 many images. To enable Keep-Alive connections, set
2247 <code>KeepAlive On</code>.</p>
2249 <p>For HTTP/1.0 clients, Keep-Alive connections will only be
2250 used if they are specifically requested by a client. In
2251 addition, a Keep-Alive connection with an HTTP/1.0 client can
2252 only be used when the length of the content is known in
2253 advance. This implies that dynamic content such as CGI output,
2254 SSI pages, and server-generated directory listings will
2255 generally not use Keep-Alive connections to HTTP/1.0 clients.
2256 For HTTP/1.1 clients, persistent connections are the default
2257 unless otherwise specified. If the client requests it, chunked
2258 encoding will be used in order to send content of unknown
2259 length over persistent connections.</p>
2261 <p>When a client uses a Keep-Alive connection, it will be counted
2262 as a single "request" for the <code class="directive"><a href="../mod/mpm_common.html#maxconnectionsperchild">MaxConnectionsPerChild</a></code> directive, regardless
2263 of how many requests are sent using the connection.</p>
2267 <li><code class="directive"><a href="#maxkeepaliverequests">MaxKeepAliveRequests</a></code></li>
2270 <div class="top"><a href="#page-header"><img alt="top" src="../images/up.gif" /></a></div>
2271 <div class="directive-section"><h2><a name="KeepAliveTimeout" id="KeepAliveTimeout">KeepAliveTimeout</a> <a name="keepalivetimeout" id="keepalivetimeout">Directive</a></h2>
2272 <table class="directive">
2273 <tr><th><a href="directive-dict.html#Description">Description:</a></th><td>Amount of time the server will wait for subsequent
2274 requests on a persistent connection</td></tr>
2275 <tr><th><a href="directive-dict.html#Syntax">Syntax:</a></th><td><code>KeepAliveTimeout <var>num</var>[ms]</code></td></tr>
2276 <tr><th><a href="directive-dict.html#Default">Default:</a></th><td><code>KeepAliveTimeout 5</code></td></tr>
2277 <tr><th><a href="directive-dict.html#Context">Context:</a></th><td>server config, virtual host</td></tr>
2278 <tr><th><a href="directive-dict.html#Status">Status:</a></th><td>Core</td></tr>
2279 <tr><th><a href="directive-dict.html#Module">Module:</a></th><td>core</td></tr>
2281 <p>The number of seconds Apache httpd will wait for a subsequent
2282 request before closing the connection. By adding a postfix of ms the
2283 timeout can be also set in milliseconds. Once a request has been
2284 received, the timeout value specified by the
2285 <code class="directive"><a href="#timeout">Timeout</a></code> directive applies.</p>
2287 <p>Setting <code class="directive">KeepAliveTimeout</code> to a high value
2288 may cause performance problems in heavily loaded servers. The
2289 higher the timeout, the more server processes will be kept
2290 occupied waiting on connections with idle clients.</p>
2292 <p>If <code class="directive">KeepAliveTimeout</code> is <strong>not</strong>
2293 set for a name-based virtual host, the value of the first defined
2294 virtual host best matching the local IP and port will be used.</p>
2297 <div class="top"><a href="#page-header"><img alt="top" src="../images/up.gif" /></a></div>
2298 <div class="directive-section"><h2><a name="Limit" id="Limit"><Limit></a> <a name="limit" id="limit">Directive</a></h2>
2299 <table class="directive">
2300 <tr><th><a href="directive-dict.html#Description">Description:</a></th><td>Restrict enclosed access controls to only certain HTTP
2302 <tr><th><a href="directive-dict.html#Syntax">Syntax:</a></th><td><code><Limit <var>method</var> [<var>method</var>] ... > ...
2303 </Limit></code></td></tr>
2304 <tr><th><a href="directive-dict.html#Context">Context:</a></th><td>directory, .htaccess</td></tr>
2305 <tr><th><a href="directive-dict.html#Override">Override:</a></th><td>AuthConfig, Limit</td></tr>
2306 <tr><th><a href="directive-dict.html#Status">Status:</a></th><td>Core</td></tr>
2307 <tr><th><a href="directive-dict.html#Module">Module:</a></th><td>core</td></tr>
2309 <p>Access controls are normally effective for
2310 <strong>all</strong> access methods, and this is the usual
2311 desired behavior. <strong>In the general case, access control
2312 directives should not be placed within a
2313 <code class="directive"><Limit></code> section.</strong></p>
2315 <p>The purpose of the <code class="directive"><Limit></code>
2316 directive is to restrict the effect of the access controls to the
2317 nominated HTTP methods. For all other methods, the access
2318 restrictions that are enclosed in the <code class="directive"><Limit></code> bracket <strong>will have no
2319 effect</strong>. The following example applies the access control
2320 only to the methods <code>POST</code>, <code>PUT</code>, and
2321 <code>DELETE</code>, leaving all other methods unprotected:</p>
2323 <pre class="prettyprint lang-config"><Limit POST PUT DELETE>
2325 </Limit></pre>
2328 <p>The method names listed can be one or more of: <code>GET</code>,
2329 <code>POST</code>, <code>PUT</code>, <code>DELETE</code>,
2330 <code>CONNECT</code>, <code>OPTIONS</code>,
2331 <code>PATCH</code>, <code>PROPFIND</code>, <code>PROPPATCH</code>,
2332 <code>MKCOL</code>, <code>COPY</code>, <code>MOVE</code>,
2333 <code>LOCK</code>, and <code>UNLOCK</code>. <strong>The method name is
2334 case-sensitive.</strong> If <code>GET</code> is used, it will also
2335 restrict <code>HEAD</code> requests. The <code>TRACE</code> method
2336 cannot be limited (see <code class="directive"><a href="#traceenable">TraceEnable</a></code>).</p>
2338 <div class="warning">A <code class="directive"><a href="#limitexcept"><LimitExcept></a></code> section should always be
2339 used in preference to a <code class="directive"><Limit></code>
2340 section when restricting access, since a <code class="directive"><a href="#limitexcept"><LimitExcept></a></code> section provides protection
2341 against arbitrary methods.</div>
2343 <p>The <code class="directive"><Limit></code> and
2344 <code class="directive"><a href="#limitexcept"><LimitExcept></a></code>
2345 directives may be nested. In this case, each successive level of
2346 <code class="directive"><Limit></code> or <code class="directive"><a href="#limitexcept"><LimitExcept></a></code> directives must
2347 further restrict the set of methods to which access controls apply.</p>
2349 <div class="warning">When using
2350 <code class="directive"><Limit></code> or
2351 <code class="directive"><LimitExcept></code> directives with
2352 the <code class="directive"><a href="../mod/mod_authz_core.html#require">Require</a></code> directive,
2353 note that the first <code class="directive"><a href="../mod/mod_authz_core.html#require">Require</a></code>
2354 to succeed authorizes the request, regardless of the presence of other
2355 <code class="directive"><a href="../mod/mod_authz_core.html#require">Require</a></code> directives.</div>
2357 <p>For example, given the following configuration, all users will
2358 be authorized for <code>POST</code> requests, and the
2359 <code>Require group editors</code> directive will be ignored
2362 <pre class="prettyprint lang-config"><LimitExcept GET>
2364 </LimitExcept>
2366 Require group editors
2367 </Limit></pre>
2371 <div class="top"><a href="#page-header"><img alt="top" src="../images/up.gif" /></a></div>
2372 <div class="directive-section"><h2><a name="LimitExcept" id="LimitExcept"><LimitExcept></a> <a name="limitexcept" id="limitexcept">Directive</a></h2>
2373 <table class="directive">
2374 <tr><th><a href="directive-dict.html#Description">Description:</a></th><td>Restrict access controls to all HTTP methods
2375 except the named ones</td></tr>
2376 <tr><th><a href="directive-dict.html#Syntax">Syntax:</a></th><td><code><LimitExcept <var>method</var> [<var>method</var>] ... > ...
2377 </LimitExcept></code></td></tr>
2378 <tr><th><a href="directive-dict.html#Context">Context:</a></th><td>directory, .htaccess</td></tr>
2379 <tr><th><a href="directive-dict.html#Override">Override:</a></th><td>AuthConfig, Limit</td></tr>
2380 <tr><th><a href="directive-dict.html#Status">Status:</a></th><td>Core</td></tr>
2381 <tr><th><a href="directive-dict.html#Module">Module:</a></th><td>core</td></tr>
2383 <p><code class="directive"><LimitExcept></code> and
2384 <code></LimitExcept></code> are used to enclose
2385 a group of access control directives which will then apply to any
2386 HTTP access method <strong>not</strong> listed in the arguments;
2387 i.e., it is the opposite of a <code class="directive"><a href="#limit"><Limit></a></code> section and can be used to control
2388 both standard and nonstandard/unrecognized methods. See the
2389 documentation for <code class="directive"><a href="#limit"><Limit></a></code> for more details.</p>
2393 <pre class="prettyprint lang-config"><LimitExcept POST GET>
2395 </LimitExcept></pre>
2400 <div class="top"><a href="#page-header"><img alt="top" src="../images/up.gif" /></a></div>
2401 <div class="directive-section"><h2><a name="LimitInternalRecursion" id="LimitInternalRecursion">LimitInternalRecursion</a> <a name="limitinternalrecursion" id="limitinternalrecursion">Directive</a></h2>
2402 <table class="directive">
2403 <tr><th><a href="directive-dict.html#Description">Description:</a></th><td>Determine maximum number of internal redirects and nested
2404 subrequests</td></tr>
2405 <tr><th><a href="directive-dict.html#Syntax">Syntax:</a></th><td><code>LimitInternalRecursion <var>number</var> [<var>number</var>]</code></td></tr>
2406 <tr><th><a href="directive-dict.html#Default">Default:</a></th><td><code>LimitInternalRecursion 10</code></td></tr>
2407 <tr><th><a href="directive-dict.html#Context">Context:</a></th><td>server config, virtual host</td></tr>
2408 <tr><th><a href="directive-dict.html#Status">Status:</a></th><td>Core</td></tr>
2409 <tr><th><a href="directive-dict.html#Module">Module:</a></th><td>core</td></tr>
2411 <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
2412 redirects the original request to a CGI script. A subrequest is Apache httpd's
2413 mechanism to find out what would happen for some URI if it were requested.
2414 For example, <code class="module"><a href="../mod/mod_dir.html">mod_dir</a></code> uses subrequests to look for the
2415 files listed in the <code class="directive"><a href="../mod/mod_dir.html#directoryindex">DirectoryIndex</a></code>
2418 <p><code class="directive">LimitInternalRecursion</code> prevents the server
2419 from crashing when entering an infinite loop of internal redirects or
2420 subrequests. Such loops are usually caused by misconfigurations.</p>
2422 <p>The directive stores two different limits, which are evaluated on
2423 per-request basis. The first <var>number</var> is the maximum number of
2424 internal redirects that may follow each other. The second <var>number</var>
2425 determines how deeply subrequests may be nested. If you specify only one
2426 <var>number</var>, it will be assigned to both limits.</p>
2428 <pre class="prettyprint lang-config">LimitInternalRecursion 5</pre>
2432 <div class="top"><a href="#page-header"><img alt="top" src="../images/up.gif" /></a></div>
2433 <div class="directive-section"><h2><a name="LimitRequestBody" id="LimitRequestBody">LimitRequestBody</a> <a name="limitrequestbody" id="limitrequestbody">Directive</a></h2>
2434 <table class="directive">
2435 <tr><th><a href="directive-dict.html#Description">Description:</a></th><td>Restricts the total size of the HTTP request body sent
2436 from the client</td></tr>
2437 <tr><th><a href="directive-dict.html#Syntax">Syntax:</a></th><td><code>LimitRequestBody <var>bytes</var></code></td></tr>
2438 <tr><th><a href="directive-dict.html#Default">Default:</a></th><td><code>LimitRequestBody 0</code></td></tr>
2439 <tr><th><a href="directive-dict.html#Context">Context:</a></th><td>server config, virtual host, directory, .htaccess</td></tr>
2440 <tr><th><a href="directive-dict.html#Override">Override:</a></th><td>All</td></tr>
2441 <tr><th><a href="directive-dict.html#Status">Status:</a></th><td>Core</td></tr>
2442 <tr><th><a href="directive-dict.html#Module">Module:</a></th><td>core</td></tr>
2444 <p>This directive specifies the number of <var>bytes</var> from 0
2445 (meaning unlimited) to 2147483647 (2GB) that are allowed in a
2446 request body. See the note below for the limited applicability
2447 to proxy requests.</p>
2449 <p>The <code class="directive">LimitRequestBody</code> directive allows
2450 the user to set a limit on the allowed size of an HTTP request
2451 message body within the context in which the directive is given
2452 (server, per-directory, per-file or per-location). If the client
2453 request exceeds that limit, the server will return an error
2454 response instead of servicing the request. The size of a normal
2455 request message body will vary greatly depending on the nature of
2456 the resource and the methods allowed on that resource. CGI scripts
2457 typically use the message body for retrieving form information.
2458 Implementations of the <code>PUT</code> method will require
2459 a value at least as large as any representation that the server
2460 wishes to accept for that resource.</p>
2462 <p>This directive gives the server administrator greater
2463 control over abnormal client request behavior, which may be
2464 useful for avoiding some forms of denial-of-service
2467 <p>If, for example, you are permitting file upload to a particular
2468 location and wish to limit the size of the uploaded file to 100K,
2469 you might use the following directive:</p>
2471 <pre class="prettyprint lang-config">LimitRequestBody 102400</pre>
2474 <div class="note"><p>For a full description of how this directive is interpreted by
2475 proxy requests, see the <code class="module"><a href="../mod/mod_proxy.html">mod_proxy</a></code> documentation.</p>
2480 <div class="top"><a href="#page-header"><img alt="top" src="../images/up.gif" /></a></div>
2481 <div class="directive-section"><h2><a name="LimitRequestFields" id="LimitRequestFields">LimitRequestFields</a> <a name="limitrequestfields" id="limitrequestfields">Directive</a></h2>
2482 <table class="directive">
2483 <tr><th><a href="directive-dict.html#Description">Description:</a></th><td>Limits the number of HTTP request header fields that
2484 will be accepted from the client</td></tr>
2485 <tr><th><a href="directive-dict.html#Syntax">Syntax:</a></th><td><code>LimitRequestFields <var>number</var></code></td></tr>
2486 <tr><th><a href="directive-dict.html#Default">Default:</a></th><td><code>LimitRequestFields 100</code></td></tr>
2487 <tr><th><a href="directive-dict.html#Context">Context:</a></th><td>server config, virtual host</td></tr>
2488 <tr><th><a href="directive-dict.html#Status">Status:</a></th><td>Core</td></tr>
2489 <tr><th><a href="directive-dict.html#Module">Module:</a></th><td>core</td></tr>
2491 <p><var>Number</var> is an integer from 0 (meaning unlimited) to
2492 32767. The default value is defined by the compile-time
2493 constant <code>DEFAULT_LIMIT_REQUEST_FIELDS</code> (100 as
2496 <p>The <code class="directive">LimitRequestFields</code> directive allows
2497 the server administrator to modify the limit on the number of
2498 request header fields allowed in an HTTP request. A server needs
2499 this value to be larger than the number of fields that a normal
2500 client request might include. The number of request header fields
2501 used by a client rarely exceeds 20, but this may vary among
2502 different client implementations, often depending upon the extent
2503 to which a user has configured their browser to support detailed
2504 content negotiation. Optional HTTP extensions are often expressed
2505 using request header fields.</p>
2507 <p>This directive gives the server administrator greater
2508 control over abnormal client request behavior, which may be
2509 useful for avoiding some forms of denial-of-service attacks.
2510 The value should be increased if normal clients see an error
2511 response from the server that indicates too many fields were
2512 sent in the request.</p>
2516 <pre class="prettyprint lang-config">LimitRequestFields 50</pre>
2519 <div class="warning"><h3>Warning</h3>
2520 <p> When name-based virtual hosting is used, the value for this
2521 directive is taken from the default (first-listed) virtual host for the
2522 local IP and port combination.</p>
2527 <div class="top"><a href="#page-header"><img alt="top" src="../images/up.gif" /></a></div>
2528 <div class="directive-section"><h2><a name="LimitRequestFieldSize" id="LimitRequestFieldSize">LimitRequestFieldSize</a> <a name="limitrequestfieldsize" id="limitrequestfieldsize">Directive</a></h2>
2529 <table class="directive">
2530 <tr><th><a href="directive-dict.html#Description">Description:</a></th><td>Limits the size of the HTTP request header allowed from the
2532 <tr><th><a href="directive-dict.html#Syntax">Syntax:</a></th><td><code>LimitRequestFieldSize <var>bytes</var></code></td></tr>
2533 <tr><th><a href="directive-dict.html#Default">Default:</a></th><td><code>LimitRequestFieldSize 8190</code></td></tr>
2534 <tr><th><a href="directive-dict.html#Context">Context:</a></th><td>server config, virtual host</td></tr>
2535 <tr><th><a href="directive-dict.html#Status">Status:</a></th><td>Core</td></tr>
2536 <tr><th><a href="directive-dict.html#Module">Module:</a></th><td>core</td></tr>
2538 <p>This directive specifies the number of <var>bytes</var>
2539 that will be allowed in an HTTP request header.</p>
2541 <p>The <code class="directive">LimitRequestFieldSize</code> directive
2542 allows the server administrator to set the limit
2543 on the allowed size of an HTTP request header field. A server
2544 needs this value to be large enough to hold any one header field
2545 from a normal client request. The size of a normal request header
2546 field will vary greatly among different client implementations,
2547 often depending upon the extent to which a user has configured
2548 their browser to support detailed content negotiation. SPNEGO
2549 authentication headers can be up to 12392 bytes.</p>
2551 <p>This directive gives the server administrator greater
2552 control over abnormal client request behavior, which may be
2553 useful for avoiding some forms of denial-of-service attacks.</p>
2557 <pre class="prettyprint lang-config">LimitRequestFieldSize 4094</pre>
2560 <div class="note">Under normal conditions, the value should not be changed from
2563 <div class="warning"><h3>Warning</h3>
2564 <p> When name-based virtual hosting is used, the value for this
2565 directive is taken from the default (first-listed) virtual host best
2566 matching the current IP address and port combination.</p>
2570 <div class="top"><a href="#page-header"><img alt="top" src="../images/up.gif" /></a></div>
2571 <div class="directive-section"><h2><a name="LimitRequestLine" id="LimitRequestLine">LimitRequestLine</a> <a name="limitrequestline" id="limitrequestline">Directive</a></h2>
2572 <table class="directive">
2573 <tr><th><a href="directive-dict.html#Description">Description:</a></th><td>Limit the size of the HTTP request line that will be accepted
2574 from the client</td></tr>
2575 <tr><th><a href="directive-dict.html#Syntax">Syntax:</a></th><td><code>LimitRequestLine <var>bytes</var></code></td></tr>
2576 <tr><th><a href="directive-dict.html#Default">Default:</a></th><td><code>LimitRequestLine 8190</code></td></tr>
2577 <tr><th><a href="directive-dict.html#Context">Context:</a></th><td>server config, virtual host</td></tr>
2578 <tr><th><a href="directive-dict.html#Status">Status:</a></th><td>Core</td></tr>
2579 <tr><th><a href="directive-dict.html#Module">Module:</a></th><td>core</td></tr>
2581 <p>This directive sets the number of <var>bytes</var> that will be
2582 allowed on the HTTP request-line.</p>
2584 <p>The <code class="directive">LimitRequestLine</code> directive allows
2585 the server administrator to set the limit on the allowed size
2586 of a client's HTTP request-line. Since the request-line consists of the
2587 HTTP method, URI, and protocol version, the
2588 <code class="directive">LimitRequestLine</code> directive places a
2589 restriction on the length of a request-URI allowed for a request
2590 on the server. A server needs this value to be large enough to
2591 hold any of its resource names, including any information that
2592 might be passed in the query part of a <code>GET</code> request.</p>
2594 <p>This directive gives the server administrator greater
2595 control over abnormal client request behavior, which may be
2596 useful for avoiding some forms of denial-of-service attacks.</p>
2600 <pre class="prettyprint lang-config">LimitRequestLine 4094</pre>
2603 <div class="note">Under normal conditions, the value should not be changed from
2606 <div class="warning"><h3>Warning</h3>
2607 <p> When name-based virtual hosting is used, the value for this
2608 directive is taken from the default (first-listed) virtual host best
2609 matching the current IP address and port combination.</p>
2614 <div class="top"><a href="#page-header"><img alt="top" src="../images/up.gif" /></a></div>
2615 <div class="directive-section"><h2><a name="LimitXMLRequestBody" id="LimitXMLRequestBody">LimitXMLRequestBody</a> <a name="limitxmlrequestbody" id="limitxmlrequestbody">Directive</a></h2>
2616 <table class="directive">
2617 <tr><th><a href="directive-dict.html#Description">Description:</a></th><td>Limits the size of an XML-based request body</td></tr>
2618 <tr><th><a href="directive-dict.html#Syntax">Syntax:</a></th><td><code>LimitXMLRequestBody <var>bytes</var></code></td></tr>
2619 <tr><th><a href="directive-dict.html#Default">Default:</a></th><td><code>LimitXMLRequestBody 1000000</code></td></tr>
2620 <tr><th><a href="directive-dict.html#Context">Context:</a></th><td>server config, virtual host, directory, .htaccess</td></tr>
2621 <tr><th><a href="directive-dict.html#Override">Override:</a></th><td>All</td></tr>
2622 <tr><th><a href="directive-dict.html#Status">Status:</a></th><td>Core</td></tr>
2623 <tr><th><a href="directive-dict.html#Module">Module:</a></th><td>core</td></tr>
2625 <p>Limit (in bytes) on maximum size of an XML-based request
2626 body. A value of <code>0</code> will disable any checking.</p>
2630 <pre class="prettyprint lang-config">LimitXMLRequestBody 0</pre>
2635 <div class="top"><a href="#page-header"><img alt="top" src="../images/up.gif" /></a></div>
2636 <div class="directive-section"><h2><a name="Location" id="Location"><Location></a> <a name="location" id="location">Directive</a></h2>
2637 <table class="directive">
2638 <tr><th><a href="directive-dict.html#Description">Description:</a></th><td>Applies the enclosed directives only to matching
2640 <tr><th><a href="directive-dict.html#Syntax">Syntax:</a></th><td><code><Location
2641 <var>URL-path</var>|<var>URL</var>> ... </Location></code></td></tr>
2642 <tr><th><a href="directive-dict.html#Context">Context:</a></th><td>server config, virtual host</td></tr>
2643 <tr><th><a href="directive-dict.html#Status">Status:</a></th><td>Core</td></tr>
2644 <tr><th><a href="directive-dict.html#Module">Module:</a></th><td>core</td></tr>
2646 <p>The <code class="directive"><Location></code> directive
2647 limits the scope of the enclosed directives by URL. It is similar to the
2648 <code class="directive"><a href="#directory"><Directory></a></code>
2649 directive, and starts a subsection which is terminated with a
2650 <code></Location></code> directive. <code class="directive"><Location></code> sections are processed in the
2651 order they appear in the configuration file, after the <code class="directive"><a href="#directory"><Directory></a></code> sections and
2652 <code>.htaccess</code> files are read, and after the <code class="directive"><a href="#files"><Files></a></code> sections.</p>
2654 <p><code class="directive"><Location></code> sections operate
2655 completely outside the filesystem. This has several consequences.
2656 Most importantly, <code class="directive"><Location></code>
2657 directives should not be used to control access to filesystem
2658 locations. Since several different URLs may map to the same
2659 filesystem location, such access controls may by circumvented.</p>
2661 <p>The enclosed directives will be applied to the request if the path component
2662 of the URL meets <em>any</em> of the following criteria:
2665 <li>The specified location matches exactly the path component of the URL.
2667 <li>The specified location, which ends in a forward slash, is a prefix
2668 of the path component of the URL (treated as a context root).
2670 <li>The specified location, with the addition of a trailing slash, is a
2671 prefix of the path component of the URL (also treated as a context root).
2675 In the example below, where no trailing slash is used, requests to
2676 /private1, /private1/ and /private1/file.txt will have the enclosed
2677 directives applied, but /private1other would not.
2679 <pre class="prettyprint lang-config"><Location "/private1">
2681 </Location></pre>
2684 In the example below, where a trailing slash is used, requests to
2685 /private2/ and /private2/file.txt will have the enclosed
2686 directives applied, but /private2 and /private2other would not.
2688 <pre class="prettyprint lang-config"><Location "/private2<em>/</em>">
2690 </Location></pre>
2693 <div class="note"><h3>When to use <code class="directive"><Location></code></h3>
2695 <p>Use <code class="directive"><Location></code> to apply
2696 directives to content that lives outside the filesystem. For
2697 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
2698 <code><Location "/"></code>, which is an easy way to
2699 apply a configuration to the entire server.</p>
2702 <p>For all origin (non-proxy) requests, the URL to be matched is a
2703 URL-path of the form <code>/path/</code>. <em>No scheme, hostname,
2704 port, or query string may be included.</em> For proxy requests, the
2705 URL to be matched is of the form
2706 <code>scheme://servername/path</code>, and you must include the
2709 <p>The URL may use wildcards. In a wild-card string, <code>?</code> matches
2710 any single character, and <code>*</code> matches any sequences of
2711 characters. Neither wildcard character matches a / in the URL-path.</p>
2713 <p><a class="glossarylink" href="../glossary.html#regex" title="see glossary">Regular expressions</a>
2714 can also be used, with the addition of the <code>~</code>
2715 character. For example:</p>
2717 <pre class="prettyprint lang-config"><Location ~ "/(extra|special)/data">
2719 </Location></pre>
2722 <p>would match URLs that contained the substring <code>/extra/data</code>
2723 or <code>/special/data</code>. The directive <code class="directive"><a href="#locationmatch"><LocationMatch></a></code> behaves
2724 identical to the regex version of <code class="directive"><Location></code>, and is preferred, for the
2725 simple reason that <code>~</code> is hard to distinguish from
2726 <code>-</code> in many fonts.</p>
2728 <p>The <code class="directive"><Location></code>
2729 functionality is especially useful when combined with the
2730 <code class="directive"><a href="#sethandler">SetHandler</a></code>
2731 directive. For example, to enable status requests but allow them
2732 only from browsers at <code>example.com</code>, you might use:</p>
2734 <pre class="prettyprint lang-config"><Location "/status">
2735 SetHandler server-status
2736 Require host example.com
2737 </Location></pre>
2740 <div class="note"><h3>Note about / (slash)</h3>
2741 <p>The slash character has special meaning depending on where in a
2742 URL it appears. People may be used to its behavior in the filesystem
2743 where multiple adjacent slashes are frequently collapsed to a single
2744 slash (<em>i.e.</em>, <code>/home///foo</code> is the same as
2745 <code>/home/foo</code>). In URL-space this is not necessarily true.
2746 The <code class="directive"><a href="#locationmatch"><LocationMatch></a></code>
2747 directive and the regex version of <code class="directive"><Location></code> require you to explicitly specify multiple
2748 slashes if that is your intention.</p>
2750 <p>For example, <code><LocationMatch "^/abc"></code> would match
2751 the request URL <code>/abc</code> but not the request URL <code>
2752 //abc</code>. The (non-regex) <code class="directive"><Location></code> directive behaves similarly when used for
2753 proxy requests. But when (non-regex) <code class="directive"><Location></code> is used for non-proxy requests it will
2754 implicitly match multiple slashes with a single slash. For example,
2755 if you specify <code><Location "/abc/def"></code> and the
2756 request is to <code>/abc//def</code> then it will match.</p>
2761 <li><a href="../sections.html">How <Directory>, <Location>
2762 and <Files> sections work</a> for an explanation of how these
2763 different sections are combined when a request is received.</li>
2764 <li><code class="directive"><a href="#locationmatch">LocationMatch</a></code></li>
2767 <div class="top"><a href="#page-header"><img alt="top" src="../images/up.gif" /></a></div>
2768 <div class="directive-section"><h2><a name="LocationMatch" id="LocationMatch"><LocationMatch></a> <a name="locationmatch" id="locationmatch">Directive</a></h2>
2769 <table class="directive">
2770 <tr><th><a href="directive-dict.html#Description">Description:</a></th><td>Applies the enclosed directives only to regular-expression
2771 matching URLs</td></tr>
2772 <tr><th><a href="directive-dict.html#Syntax">Syntax:</a></th><td><code><LocationMatch
2773 <var>regex</var>> ... </LocationMatch></code></td></tr>
2774 <tr><th><a href="directive-dict.html#Context">Context:</a></th><td>server config, virtual host</td></tr>
2775 <tr><th><a href="directive-dict.html#Status">Status:</a></th><td>Core</td></tr>
2776 <tr><th><a href="directive-dict.html#Module">Module:</a></th><td>core</td></tr>
2778 <p>The <code class="directive"><LocationMatch></code> directive
2779 limits the scope of the enclosed directives by URL, in an identical manner
2780 to <code class="directive"><a href="#location"><Location></a></code>. However,
2781 it takes a <a class="glossarylink" href="../glossary.html#regex" title="see glossary">regular expression</a>
2782 as an argument instead of a simple string. For example:</p>
2784 <pre class="prettyprint lang-config"><LocationMatch "/(extra|special)/data">
2786 </LocationMatch></pre>
2789 <p>would match URLs that contained the substring <code>/extra/data</code>
2790 or <code>/special/data</code>.</p>
2792 <div class="note"><p>If the intent is that a URL <strong>starts with</strong>
2793 <code>/extra/data</code>, rather than merely
2794 <strong>contains</strong> <code>/extra/data</code>, prefix the
2795 regular expression with a <code>^</code> to require this.</p>
2797 <pre class="prettyprint lang-config"><LocationMatch "^/(extra|special)/data"></pre>
2801 <p>From 2.4.8 onwards, named groups and backreferences are captured and
2802 written to the environment with the corresponding name prefixed with
2803 "MATCH_" and in upper case. This allows elements of URLs to be referenced
2804 from within <a href="../expr.html">expressions</a> and modules like
2805 <code class="module"><a href="../mod/mod_rewrite.html">mod_rewrite</a></code>. In order to prevent confusion, numbered
2806 (unnamed) backreferences are ignored. Use named groups instead.</p>
2808 <pre class="prettyprint lang-config"><LocationMatch "^/combined/(?<sitename>[^/]+)">
2809 require ldap-group cn=%{env:MATCH_SITENAME},ou=combined,o=Example
2810 </LocationMatch></pre>
2815 <li><a href="../sections.html">How <Directory>, <Location>
2816 and <Files> sections work</a> for an explanation of how these
2817 different sections are combined when a request is received</li>
2820 <div class="top"><a href="#page-header"><img alt="top" src="../images/up.gif" /></a></div>
2821 <div class="directive-section"><h2><a name="LogLevel" id="LogLevel">LogLevel</a> <a name="loglevel" id="loglevel">Directive</a></h2>
2822 <table class="directive">
2823 <tr><th><a href="directive-dict.html#Description">Description:</a></th><td>Controls the verbosity of the ErrorLog</td></tr>
2824 <tr><th><a href="directive-dict.html#Syntax">Syntax:</a></th><td><code>LogLevel [<var>module</var>:]<var>level</var>
2825 [<var>module</var>:<var>level</var>] ...
2827 <tr><th><a href="directive-dict.html#Default">Default:</a></th><td><code>LogLevel warn</code></td></tr>
2828 <tr><th><a href="directive-dict.html#Context">Context:</a></th><td>server config, virtual host, directory</td></tr>
2829 <tr><th><a href="directive-dict.html#Status">Status:</a></th><td>Core</td></tr>
2830 <tr><th><a href="directive-dict.html#Module">Module:</a></th><td>core</td></tr>
2831 <tr><th><a href="directive-dict.html#Compatibility">Compatibility:</a></th><td>Per-module and per-directory configuration is available in
2832 Apache HTTP Server 2.3.6 and later</td></tr>
2834 <p><code class="directive">LogLevel</code> adjusts the verbosity of the
2835 messages recorded in the error logs (see <code class="directive"><a href="#errorlog">ErrorLog</a></code> directive). The following
2836 <var>level</var>s are available, in order of decreasing
2839 <table class="bordered">
2842 <th><strong>Level</strong> </th>
2844 <th><strong>Description</strong> </th>
2846 <th><strong>Example</strong> </th>
2850 <td><code>emerg</code> </td>
2852 <td>Emergencies - system is unusable.</td>
2854 <td>"Child cannot open lock file. Exiting"</td>
2858 <td><code>alert</code> </td>
2860 <td>Action must be taken immediately.</td>
2862 <td>"getpwuid: couldn't determine user name from uid"</td>
2866 <td><code>crit</code> </td>
2868 <td>Critical Conditions.</td>
2870 <td>"socket: Failed to get a socket, exiting child"</td>
2874 <td><code>error</code> </td>
2876 <td>Error conditions.</td>
2878 <td>"Premature end of script headers"</td>
2882 <td><code>warn</code> </td>
2884 <td>Warning conditions.</td>
2886 <td>"child process 1234 did not exit, sending another
2891 <td><code>notice</code> </td>
2893 <td>Normal but significant condition.</td>
2895 <td>"httpd: caught SIGBUS, attempting to dump core in
2900 <td><code>info</code> </td>
2902 <td>Informational.</td>
2904 <td>"Server seems busy, (you may need to increase
2905 StartServers, or Min/MaxSpareServers)..."</td>
2909 <td><code>debug</code> </td>
2911 <td>Debug-level messages</td>
2913 <td>"Opening config file ..."</td>
2916 <td><code>trace1</code> </td>
2918 <td>Trace messages</td>
2920 <td>"proxy: FTP: control connection complete"</td>
2923 <td><code>trace2</code> </td>
2925 <td>Trace messages</td>
2927 <td>"proxy: CONNECT: sending the CONNECT request to the remote proxy"</td>
2930 <td><code>trace3</code> </td>
2932 <td>Trace messages</td>
2934 <td>"openssl: Handshake: start"</td>
2937 <td><code>trace4</code> </td>
2939 <td>Trace messages</td>
2941 <td>"read from buffered SSL brigade, mode 0, 17 bytes"</td>
2944 <td><code>trace5</code> </td>
2946 <td>Trace messages</td>
2948 <td>"map lookup FAILED: map=rewritemap key=keyname"</td>
2951 <td><code>trace6</code> </td>
2953 <td>Trace messages</td>
2955 <td>"cache lookup FAILED, forcing new map lookup"</td>
2958 <td><code>trace7</code> </td>
2960 <td>Trace messages, dumping large amounts of data</td>
2962 <td>"| 0000: 02 23 44 30 13 40 ac 34 df 3d bf 9a 19 49 39 15 |"</td>
2965 <td><code>trace8</code> </td>
2967 <td>Trace messages, dumping large amounts of data</td>
2969 <td>"| 0000: 02 23 44 30 13 40 ac 34 df 3d bf 9a 19 49 39 15 |"</td>
2973 <p>When a particular level is specified, messages from all
2974 other levels of higher significance will be reported as well.
2975 <em>E.g.</em>, when <code>LogLevel info</code> is specified,
2976 then messages with log levels of <code>notice</code> and
2977 <code>warn</code> will also be posted.</p>
2979 <p>Using a level of at least <code>crit</code> is
2984 <pre class="prettyprint lang-config">LogLevel notice</pre>
2987 <div class="note"><h3>Note</h3>
2988 <p>When logging to a regular file, messages of the level
2989 <code>notice</code> cannot be suppressed and thus are always
2990 logged. However, this doesn't apply when logging is done
2991 using <code>syslog</code>.</p>
2994 <p>Specifying a level without a module name will reset the level
2995 for all modules to that level. Specifying a level with a module
2996 name will set the level for that module only. It is possible to
2997 use the module source file name, the module identifier, or the
2998 module identifier with the trailing <code>_module</code> omitted
2999 as module specification. This means the following three specifications
3002 <pre class="prettyprint lang-config">LogLevel info ssl:warn
3003 LogLevel info mod_ssl.c:warn
3004 LogLevel info ssl_module:warn</pre>
3007 <p>It is also possible to change the level per directory:</p>
3009 <pre class="prettyprint lang-config">LogLevel info
3010 <Directory "/usr/local/apache/htdocs/app">
3012 </Directory></pre>
3016 Per directory loglevel configuration only affects messages that are
3017 logged after the request has been parsed and that are associated with
3018 the request. Log messages which are associated with the server or
3019 the connection are not affected. The latter can be influenced by the
3020 <code class="directive"><a href="#logleveloverride">LogLevelOverride</a></code> directive,
3026 <li><code class="directive"><a href="#errorlog">ErrorLog</a></code></li>
3027 <li><code class="directive"><a href="#errorlogformat">ErrorLogFormat</a></code></li>
3028 <li><code class="directive"><a href="#logleveloverride">LogLevelOverride</a></code></li>
3029 <li><a href="../logs.html">Apache HTTP Server Log Files</a></li>
3032 <div class="top"><a href="#page-header"><img alt="top" src="../images/up.gif" /></a></div>
3033 <div class="directive-section"><h2><a name="LogLevelOverride" id="LogLevelOverride">LogLevelOverride</a> <a name="logleveloverride" id="logleveloverride">Directive</a></h2>
3034 <table class="directive">
3035 <tr><th><a href="directive-dict.html#Description">Description:</a></th><td>Override the verbosity of the ErrorLog for certain clients</td></tr>
3036 <tr><th><a href="directive-dict.html#Syntax">Syntax:</a></th><td><code>LogLevel <var>ipaddress</var>[/<var>prefixlen</var>]
3037 [<var>module</var>:]<var>level</var> [<var>module</var>:<var>level</var>] ...
3039 <tr><th><a href="directive-dict.html#Default">Default:</a></th><td><code>unset</code></td></tr>
3040 <tr><th><a href="directive-dict.html#Context">Context:</a></th><td>server config, virtual host</td></tr>
3041 <tr><th><a href="directive-dict.html#Status">Status:</a></th><td>Core</td></tr>
3042 <tr><th><a href="directive-dict.html#Module">Module:</a></th><td>core</td></tr>
3043 <tr><th><a href="directive-dict.html#Compatibility">Compatibility:</a></th><td>Available in Apache HTTP Server 2.5.0 and later</td></tr>
3045 <p><code class="directive">LogLevelOverride</code> adjusts the
3046 <code class="directive"><a href="#loglevel">LogLevel</a></code> for requests coming from
3047 certain client IP addresses.
3048 This allows to enable verbose logging only for certain test clients.
3049 The IP address is checked at a very early state in the connection
3050 processing. Therefore, <code class="directive">LogLevelOverride</code> allows to
3051 change the log level for things like the SSL handshake which happen before
3052 a <code class="directive"><a href="#loglevel">LogLevel</a></code> directive in an
3053 <code class="directive"><a href="#if"><If></a></code> container would
3056 <p><code class="directive">LogLevelOverride</code> accepts either a single
3057 IP-address or a CIDR IP-address/len subnet specification.
3058 For the syntax of the loglevel specification, see the
3059 <code class="directive"><a href="#loglevel">LogLevel</a></code> directive.</p>
3061 <p>For requests that match a <code class="directive">LogLevelOverride</code>
3062 directive, per-directory specifications of
3063 <code class="directive"><a href="#loglevel">LogLevel</a></code> are ignored.</p>
3067 <pre class="prettyprint lang-config"> LogLevelOverride 192.0.2.0/24 ssl:trace6
3068 LogLevelOverride 192.0.2.7 ssl:trace8</pre>
3072 <code class="directive">LogLevelOverride</code> only affects
3073 log messages that are associated with the request or the connection.
3074 Log messages which are associated with the server are not affected.
3080 <li><code class="directive"><a href="#loglevel">LogLevel</a></code></li>
3083 <div class="top"><a href="#page-header"><img alt="top" src="../images/up.gif" /></a></div>
3084 <div class="directive-section"><h2><a name="MaxKeepAliveRequests" id="MaxKeepAliveRequests">MaxKeepAliveRequests</a> <a name="maxkeepaliverequests" id="maxkeepaliverequests">Directive</a></h2>
3085 <table class="directive">
3086 <tr><th><a href="directive-dict.html#Description">Description:</a></th><td>Number of requests allowed on a persistent
3087 connection</td></tr>
3088 <tr><th><a href="directive-dict.html#Syntax">Syntax:</a></th><td><code>MaxKeepAliveRequests <var>number</var></code></td></tr>
3089 <tr><th><a href="directive-dict.html#Default">Default:</a></th><td><code>MaxKeepAliveRequests 100</code></td></tr>
3090 <tr><th><a href="directive-dict.html#Context">Context:</a></th><td>server config, virtual host</td></tr>
3091 <tr><th><a href="directive-dict.html#Status">Status:</a></th><td>Core</td></tr>
3092 <tr><th><a href="directive-dict.html#Module">Module:</a></th><td>core</td></tr>
3094 <p>The <code class="directive">MaxKeepAliveRequests</code> directive
3095 limits the number of requests allowed per connection when
3096 <code class="directive"><a href="#keepalive">KeepAlive</a></code> is on. If it is
3097 set to <code>0</code>, unlimited requests will be allowed. We
3098 recommend that this setting be kept to a high value for maximum
3099 server performance.</p>
3103 <pre class="prettyprint lang-config">MaxKeepAliveRequests 500</pre>
3107 <div class="top"><a href="#page-header"><img alt="top" src="../images/up.gif" /></a></div>
3108 <div class="directive-section"><h2><a name="MaxRangeOverlaps" id="MaxRangeOverlaps">MaxRangeOverlaps</a> <a name="maxrangeoverlaps" id="maxrangeoverlaps">Directive</a></h2>
3109 <table class="directive">
3110 <tr><th><a href="directive-dict.html#Description">Description:</a></th><td>Number of overlapping ranges (eg: <code>100-200,150-300</code>) allowed before returning the complete
3112 <tr><th><a href="directive-dict.html#Syntax">Syntax:</a></th><td><code>MaxRangeOverlaps default | unlimited | none | <var>number-of-ranges</var></code></td></tr>
3113 <tr><th><a href="directive-dict.html#Default">Default:</a></th><td><code>MaxRangeOverlaps 20</code></td></tr>
3114 <tr><th><a href="directive-dict.html#Context">Context:</a></th><td>server config, virtual host, directory</td></tr>
3115 <tr><th><a href="directive-dict.html#Status">Status:</a></th><td>Core</td></tr>
3116 <tr><th><a href="directive-dict.html#Module">Module:</a></th><td>core</td></tr>
3117 <tr><th><a href="directive-dict.html#Compatibility">Compatibility:</a></th><td>Available in Apache HTTP Server 2.3.15 and later</td></tr>
3119 <p>The <code class="directive">MaxRangeOverlaps</code> directive
3120 limits the number of overlapping HTTP ranges the server is willing to
3121 return to the client. If more overlapping ranges than permitted are requested,
3122 the complete resource is returned instead.</p>
3125 <dt><strong>default</strong></dt>
3126 <dd>Limits the number of overlapping ranges to a compile-time default of 20.</dd>
3128 <dt><strong>none</strong></dt>
3129 <dd>No overlapping Range headers are allowed.</dd>
3131 <dt><strong>unlimited</strong></dt>
3132 <dd>The server does not limit the number of overlapping ranges it is
3133 willing to satisfy.</dd>
3135 <dt><var>number-of-ranges</var></dt>
3136 <dd>A positive number representing the maximum number of overlapping ranges the
3137 server is willing to satisfy.</dd>
3141 <div class="top"><a href="#page-header"><img alt="top" src="../images/up.gif" /></a></div>
3142 <div class="directive-section"><h2><a name="MaxRangeReversals" id="MaxRangeReversals">MaxRangeReversals</a> <a name="maxrangereversals" id="maxrangereversals">Directive</a></h2>
3143 <table class="directive">
3144 <tr><th><a href="directive-dict.html#Description">Description:</a></th><td>Number of range reversals (eg: <code>100-200,50-70</code>) allowed before returning the complete
3146 <tr><th><a href="directive-dict.html#Syntax">Syntax:</a></th><td><code>MaxRangeReversals default | unlimited | none | <var>number-of-ranges</var></code></td></tr>
3147 <tr><th><a href="directive-dict.html#Default">Default:</a></th><td><code>MaxRangeReversals 20</code></td></tr>
3148 <tr><th><a href="directive-dict.html#Context">Context:</a></th><td>server config, virtual host, directory</td></tr>
3149 <tr><th><a href="directive-dict.html#Status">Status:</a></th><td>Core</td></tr>
3150 <tr><th><a href="directive-dict.html#Module">Module:</a></th><td>core</td></tr>
3151 <tr><th><a href="directive-dict.html#Compatibility">Compatibility:</a></th><td>Available in Apache HTTP Server 2.3.15 and later</td></tr>
3153 <p>The <code class="directive">MaxRangeReversals</code> directive
3154 limits the number of HTTP Range reversals the server is willing to
3155 return to the client. If more ranges reversals than permitted are requested,
3156 the complete resource is returned instead.</p>
3159 <dt><strong>default</strong></dt>
3160 <dd>Limits the number of range reversals to a compile-time default of 20.</dd>
3162 <dt><strong>none</strong></dt>
3163 <dd>No Range reversals headers are allowed.</dd>
3165 <dt><strong>unlimited</strong></dt>
3166 <dd>The server does not limit the number of range reversals it is
3167 willing to satisfy.</dd>
3169 <dt><var>number-of-ranges</var></dt>
3170 <dd>A positive number representing the maximum number of range reversals the
3171 server is willing to satisfy.</dd>
3175 <div class="top"><a href="#page-header"><img alt="top" src="../images/up.gif" /></a></div>
3176 <div class="directive-section"><h2><a name="MaxRanges" id="MaxRanges">MaxRanges</a> <a name="maxranges" id="maxranges">Directive</a></h2>
3177 <table class="directive">
3178 <tr><th><a href="directive-dict.html#Description">Description:</a></th><td>Number of ranges allowed before returning the complete
3180 <tr><th><a href="directive-dict.html#Syntax">Syntax:</a></th><td><code>MaxRanges default | unlimited | none | <var>number-of-ranges</var></code></td></tr>
3181 <tr><th><a href="directive-dict.html#Default">Default:</a></th><td><code>MaxRanges 200</code></td></tr>
3182 <tr><th><a href="directive-dict.html#Context">Context:</a></th><td>server config, virtual host, directory</td></tr>
3183 <tr><th><a href="directive-dict.html#Status">Status:</a></th><td>Core</td></tr>
3184 <tr><th><a href="directive-dict.html#Module">Module:</a></th><td>core</td></tr>
3185 <tr><th><a href="directive-dict.html#Compatibility">Compatibility:</a></th><td>Available in Apache HTTP Server 2.3.15 and later</td></tr>
3187 <p>The <code class="directive">MaxRanges</code> directive
3188 limits the number of HTTP ranges the server is willing to
3189 return to the client. If more ranges than permitted are requested,
3190 the complete resource is returned instead.</p>
3193 <dt><strong>default</strong></dt>
3194 <dd>Limits the number of ranges to a compile-time default of 200.</dd>
3196 <dt><strong>none</strong></dt>
3197 <dd>Range headers are ignored.</dd>
3199 <dt><strong>unlimited</strong></dt>
3200 <dd>The server does not limit the number of ranges it is
3201 willing to satisfy.</dd>
3203 <dt><var>number-of-ranges</var></dt>
3204 <dd>A positive number representing the maximum number of ranges the
3205 server is willing to satisfy.</dd>
3209 <div class="top"><a href="#page-header"><img alt="top" src="../images/up.gif" /></a></div>
3210 <div class="directive-section"><h2><a name="MergeTrailers" id="MergeTrailers">MergeTrailers</a> <a name="mergetrailers" id="mergetrailers">Directive</a></h2>
3211 <table class="directive">
3212 <tr><th><a href="directive-dict.html#Description">Description:</a></th><td>Determines whether trailers are merged into headers</td></tr>
3213 <tr><th><a href="directive-dict.html#Syntax">Syntax:</a></th><td><code>MergeTrailers [on|off]</code></td></tr>
3214 <tr><th><a href="directive-dict.html#Default">Default:</a></th><td><code>MergeTrailers off</code></td></tr>
3215 <tr><th><a href="directive-dict.html#Context">Context:</a></th><td>server config, virtual host</td></tr>
3216 <tr><th><a href="directive-dict.html#Status">Status:</a></th><td>Core</td></tr>
3217 <tr><th><a href="directive-dict.html#Module">Module:</a></th><td>core</td></tr>
3218 <tr><th><a href="directive-dict.html#Compatibility">Compatibility:</a></th><td>2.4.11 and later</td></tr>
3220 <p>This directive controls whether HTTP trailers are copied into the
3221 internal representation of HTTP headers. This merging occurs when the
3222 request body has been completely consumed, long after most header
3223 processing would have a chance to examine or modify request headers.</p>
3224 <p>This option is provided for compatibility with releases prior to 2.4.11,
3225 where trailers were always merged.</p>
3228 <div class="top"><a href="#page-header"><img alt="top" src="../images/up.gif" /></a></div>
3229 <div class="directive-section"><h2><a name="Mutex" id="Mutex">Mutex</a> <a name="mutex" id="mutex">Directive</a></h2>
3230 <table class="directive">
3231 <tr><th><a href="directive-dict.html#Description">Description:</a></th><td>Configures mutex mechanism and lock file directory for all
3232 or specified mutexes</td></tr>
3233 <tr><th><a href="directive-dict.html#Syntax">Syntax:</a></th><td><code>Mutex <var>mechanism</var> [default|<var>mutex-name</var>] ... [OmitPID]</code></td></tr>
3234 <tr><th><a href="directive-dict.html#Default">Default:</a></th><td><code>Mutex default</code></td></tr>
3235 <tr><th><a href="directive-dict.html#Context">Context:</a></th><td>server config</td></tr>
3236 <tr><th><a href="directive-dict.html#Status">Status:</a></th><td>Core</td></tr>
3237 <tr><th><a href="directive-dict.html#Module">Module:</a></th><td>core</td></tr>
3238 <tr><th><a href="directive-dict.html#Compatibility">Compatibility:</a></th><td>Available in Apache HTTP Server 2.3.4 and later</td></tr>
3240 <p>The <code class="directive">Mutex</code> directive sets the mechanism,
3241 and optionally the lock file location, that httpd and modules use
3242 to serialize access to resources. Specify <code>default</code> as
3243 the second argument to change the settings for all mutexes; specify
3244 a mutex name (see table below) as the second argument to override
3245 defaults only for that mutex.</p>
3247 <p>The <code class="directive">Mutex</code> directive is typically used in
3248 the following exceptional situations:</p>
3251 <li>change the mutex mechanism when the default mechanism selected
3252 by <a class="glossarylink" href="../glossary.html#apr" title="see glossary">APR</a> has a functional or performance
3255 <li>change the directory used by file-based mutexes when the
3256 default directory does not support locking</li>
3259 <div class="note"><h3>Supported modules</h3>
3260 <p>This directive only configures mutexes which have been registered
3261 with the core server using the <code>ap_mutex_register()</code> API.
3262 All modules bundled with httpd support the <code class="directive">Mutex</code>
3263 directive, but third-party modules may not. Consult the documentation
3264 of the third-party module, which must indicate the mutex name(s) which
3265 can be configured if this directive is supported.</p>
3268 <p>The following mutex <em>mechanisms</em> are available:</p>
3270 <li><code>default | yes</code>
3271 <p>This selects the default locking implementation, as determined by
3272 <a class="glossarylink" href="../glossary.html#apr" title="see glossary">APR</a>. The default locking implementation can
3273 be displayed by running <code class="program"><a href="../programs/httpd.html">httpd</a></code> with the
3274 <code>-V</code> option.</p></li>
3276 <li><code>none | no</code>
3277 <p>This effectively disables the mutex, and is only allowed for a
3278 mutex if the module indicates that it is a valid choice. Consult the
3279 module documentation for more information.</p></li>
3281 <li><code>posixsem</code>
3282 <p>This is a mutex variant based on a Posix semaphore.</p>
3284 <div class="warning"><h3>Warning</h3>
3285 <p>The semaphore ownership is not recovered if a thread in the process
3286 holding the mutex segfaults, resulting in a hang of the web server.</p>
3290 <li><code>sysvsem</code>
3291 <p>This is a mutex variant based on a SystemV IPC semaphore.</p>
3293 <div class="warning"><h3>Warning</h3>
3294 <p>It is possible to "leak" SysV semaphores if processes crash
3295 before the semaphore is removed.</p>
3298 <div class="warning"><h3>Security</h3>
3299 <p>The semaphore API allows for a denial of service attack by any
3300 CGIs running under the same uid as the webserver (<em>i.e.</em>,
3301 all CGIs, unless you use something like <code class="program"><a href="../programs/suexec.html">suexec</a></code>
3302 or <code>cgiwrapper</code>).</p>
3306 <li><code>sem</code>
3307 <p>This selects the "best" available semaphore implementation, choosing
3308 between Posix and SystemV IPC semaphores, in that order.</p></li>
3310 <li><code>pthread</code>
3311 <p>This is a mutex variant based on cross-process Posix thread
3314 <div class="warning"><h3>Warning</h3>
3315 <p>On most systems, if a child process terminates abnormally while
3316 holding a mutex that uses this implementation, the server will deadlock
3317 and stop responding to requests. When this occurs, the server will
3318 require a manual restart to recover.</p>
3319 <p>Solaris is a notable exception as it provides a mechanism which
3320 usually allows the mutex to be recovered after a child process
3321 terminates abnormally while holding a mutex.</p>
3322 <p>If your system implements the
3323 <code>pthread_mutexattr_setrobust_np()</code> function, you may be able
3324 to use the <code>pthread</code> option safely.</p>
3328 <li><code>fcntl:/path/to/mutex</code>
3329 <p>This is a mutex variant where a physical (lock-)file and the
3330 <code>fcntl()</code> function are used as the mutex.</p>
3332 <div class="warning"><h3>Warning</h3>
3333 <p>When multiple mutexes based on this mechanism are used within
3334 multi-threaded, multi-process environments, deadlock errors (EDEADLK)
3335 can be reported for valid mutex operations if <code>fcntl()</code>
3336 is not thread-aware, such as on Solaris.</p>
3340 <li><code>flock:/path/to/mutex</code>
3341 <p>This is similar to the <code>fcntl:/path/to/mutex</code> method
3342 with the exception that the <code>flock()</code> function is used to
3343 provide file locking.</p></li>
3345 <li><code>file:/path/to/mutex</code>
3346 <p>This selects the "best" available file locking implementation,
3347 choosing between <code>fcntl</code> and <code>flock</code>, in that
3351 <p>Most mechanisms are only available on selected platforms, where the
3352 underlying platform and <a class="glossarylink" href="../glossary.html#apr" title="see glossary">APR</a> support it. Mechanisms
3353 which aren't available on all platforms are <em>posixsem</em>,
3354 <em>sysvsem</em>, <em>sem</em>, <em>pthread</em>, <em>fcntl</em>,
3355 <em>flock</em>, and <em>file</em>.</p>
3357 <p>With the file-based mechanisms <em>fcntl</em> and <em>flock</em>,
3358 the path, if provided, is a directory where the lock file will be created.
3359 The default directory is httpd's run-time file directory,
3360 <code class="directive"><a href="#defaultruntimedir">DefaultRuntimeDir</a></code>. If a relative
3361 path is provided, it is relative to
3362 <code class="directive"><a href="#defaultruntimedir">DefaultRuntimeDir</a></code>. Always use a local
3363 disk filesystem for <code>/path/to/mutex</code> and never a directory residing
3364 on a NFS- or AFS-filesystem. The basename of the file will be the mutex
3365 type, an optional instance string provided by the module, and unless the
3366 <code>OmitPID</code> keyword is specified, the process id of the httpd
3367 parent process will be appended to make the file name unique, avoiding
3368 conflicts when multiple httpd instances share a lock file directory. For
3369 example, if the mutex name is <code>mpm-accept</code> and the lock file
3370 directory is <code>/var/httpd/locks</code>, the lock file name for the
3371 httpd instance with parent process id 12345 would be
3372 <code>/var/httpd/locks/mpm-accept.12345</code>.</p>
3374 <div class="warning"><h3>Security</h3>
3375 <p>It is best to <em>avoid</em> putting mutex files in a world-writable
3376 directory such as <code>/var/tmp</code> because someone could create
3377 a denial of service attack and prevent the server from starting by
3378 creating a lockfile with the same name as the one the server will try
3382 <p>The following table documents the names of mutexes used by httpd
3383 and bundled modules.</p>
3385 <table class="bordered"><tr class="header">
3388 <th>Protected resource</th>
3391 <td><code>mpm-accept</code></td>
3392 <td><code class="module"><a href="../mod/prefork.html">prefork</a></code> and <code class="module"><a href="../mod/worker.html">worker</a></code> MPMs</td>
3393 <td>incoming connections, to avoid the thundering herd problem;
3394 for more information, refer to the
3395 <a href="../misc/perf-tuning.html">performance tuning</a>
3399 <td><code>authdigest-client</code></td>
3400 <td><code class="module"><a href="../mod/mod_auth_digest.html">mod_auth_digest</a></code></td>
3401 <td>client list in shared memory</td>
3404 <td><code>authdigest-opaque</code></td>
3405 <td><code class="module"><a href="../mod/mod_auth_digest.html">mod_auth_digest</a></code></td>
3406 <td>counter in shared memory</td>
3409 <td><code>ldap-cache</code></td>
3410 <td><code class="module"><a href="../mod/mod_ldap.html">mod_ldap</a></code></td>
3411 <td>LDAP result cache</td>
3414 <td><code>rewrite-map</code></td>
3415 <td><code class="module"><a href="../mod/mod_rewrite.html">mod_rewrite</a></code></td>
3416 <td>communication with external mapping programs, to avoid
3417 intermixed I/O from multiple requests</td>
3420 <td><code>ssl-cache</code></td>
3421 <td><code class="module"><a href="../mod/mod_ssl.html">mod_ssl</a></code></td>
3422 <td>SSL session cache</td>
3425 <td><code>ssl-stapling</code></td>
3426 <td><code class="module"><a href="../mod/mod_ssl.html">mod_ssl</a></code></td>
3427 <td>OCSP stapling response cache</td>
3430 <td><code>watchdog-callback</code></td>
3431 <td><code class="module"><a href="../mod/mod_watchdog.html">mod_watchdog</a></code></td>
3432 <td>callback function of a particular client module</td>
3436 <p>The <code>OmitPID</code> keyword suppresses the addition of the httpd
3437 parent process id from the lock file name.</p>
3439 <p>In the following example, the mutex mechanism for the MPM accept
3440 mutex will be changed from the compiled-in default to <code>fcntl</code>,
3441 with the associated lock file created in directory
3442 <code>/var/httpd/locks</code>. The mutex mechanism for all other mutexes
3443 will be changed from the compiled-in default to <code>sysvsem</code>.</p>
3445 <pre class="prettyprint lang-config">Mutex sysvsem default
3446 Mutex fcntl:/var/httpd/locks mpm-accept</pre>
3450 <div class="top"><a href="#page-header"><img alt="top" src="../images/up.gif" /></a></div>
3451 <div class="directive-section"><h2><a name="NameVirtualHost" id="NameVirtualHost">NameVirtualHost</a> <a name="namevirtualhost" id="namevirtualhost">Directive</a></h2>
3452 <table class="directive">
3453 <tr><th><a href="directive-dict.html#Description">Description:</a></th><td>DEPRECATED: Designates an IP address for name-virtual
3455 <tr><th><a href="directive-dict.html#Syntax">Syntax:</a></th><td><code>NameVirtualHost <var>addr</var>[:<var>port</var>]</code></td></tr>
3456 <tr><th><a href="directive-dict.html#Context">Context:</a></th><td>server config</td></tr>
3457 <tr><th><a href="directive-dict.html#Status">Status:</a></th><td>Core</td></tr>
3458 <tr><th><a href="directive-dict.html#Module">Module:</a></th><td>core</td></tr>
3461 <p>Prior to 2.3.11, <code class="directive">NameVirtualHost</code> was required
3462 to instruct the server that a particular IP address and port combination
3463 was usable as a name-based virtual host. In 2.3.11 and later,
3464 any time an IP address and port combination is used in multiple virtual
3465 hosts, name-based virtual hosting is automatically enabled for that address.</p>
3467 <p>This directive currently has no effect.</p>
3471 <li><a href="../vhosts/">Virtual Hosts
3472 documentation</a></li>
3475 <div class="top"><a href="#page-header"><img alt="top" src="../images/up.gif" /></a></div>
3476 <div class="directive-section"><h2><a name="Options" id="Options">Options</a> <a name="options" id="options">Directive</a></h2>
3477 <table class="directive">
3478 <tr><th><a href="directive-dict.html#Description">Description:</a></th><td>Configures what features are available in a particular
3480 <tr><th><a href="directive-dict.html#Syntax">Syntax:</a></th><td><code>Options
3481 [+|-]<var>option</var> [[+|-]<var>option</var>] ...</code></td></tr>
3482 <tr><th><a href="directive-dict.html#Default">Default:</a></th><td><code>Options FollowSymlinks</code></td></tr>
3483 <tr><th><a href="directive-dict.html#Context">Context:</a></th><td>server config, virtual host, directory, .htaccess</td></tr>
3484 <tr><th><a href="directive-dict.html#Override">Override:</a></th><td>Options</td></tr>
3485 <tr><th><a href="directive-dict.html#Status">Status:</a></th><td>Core</td></tr>
3486 <tr><th><a href="directive-dict.html#Module">Module:</a></th><td>core</td></tr>
3487 <tr><th><a href="directive-dict.html#Compatibility">Compatibility:</a></th><td>The default was changed from All to FollowSymlinks in 2.3.11</td></tr>
3489 <p>The <code class="directive">Options</code> directive controls which
3490 server features are available in a particular directory.</p>
3492 <p><var>option</var> can be set to <code>None</code>, in which
3493 case none of the extra features are enabled, or one or more of
3497 <dt><code>All</code></dt>
3499 <dd>All options except for <code>MultiViews</code>.</dd>
3501 <dt><code>ExecCGI</code></dt>
3504 Execution of CGI scripts using <code class="module"><a href="../mod/mod_cgi.html">mod_cgi</a></code>
3507 <dt><code>FollowSymLinks</code></dt>
3510 The server will follow symbolic links in this directory. This is
3511 the default setting.
3513 <p>Even though the server follows the symlink it does <em>not</em>
3514 change the pathname used to match against <code class="directive"><a href="#directory"><Directory></a></code> sections.</p>
3516 <p>The <code>FollowSymLinks</code> and
3517 <code>SymLinksIfOwnerMatch</code> <code class="directive"><a href="#options">Options</a></code> work only in <code class="directive"><a href="#directory"><Directory></a></code> sections or
3518 <code>.htaccess</code> files.</p>
3520 <p>Omitting this option should not be considered a security restriction,
3521 since symlink testing is subject to race conditions that make it
3525 <dt><code>Includes</code></dt>
3528 Server-side includes provided by <code class="module"><a href="../mod/mod_include.html">mod_include</a></code>
3531 <dt><code>IncludesNOEXEC</code></dt>
3535 Server-side includes are permitted, but the <code>#exec
3536 cmd</code> and <code>#exec cgi</code> are disabled. It is still
3537 possible to <code>#include virtual</code> CGI scripts from
3538 <code class="directive"><a href="../mod/mod_alias.html#scriptalias">ScriptAlias</a></code>ed
3541 <dt><code>Indexes</code></dt>
3544 If a URL which maps to a directory is requested and there
3545 is no <code class="directive"><a href="../mod/mod_dir.html#directoryindex">DirectoryIndex</a></code>
3546 (<em>e.g.</em>, <code>index.html</code>) in that directory, then
3547 <code class="module"><a href="../mod/mod_autoindex.html">mod_autoindex</a></code> will return a formatted listing
3548 of the directory.</dd>
3550 <dt><code>MultiViews</code></dt>
3553 <a href="../content-negotiation.html">Content negotiated</a>
3554 "MultiViews" are allowed using
3555 <code class="module"><a href="../mod/mod_negotiation.html">mod_negotiation</a></code>.
3556 <div class="note"><h3>Note</h3> <p>This option gets ignored if set
3557 anywhere other than <code class="directive"><a href="#directory"><Directory></a></code>, as <code class="module"><a href="../mod/mod_negotiation.html">mod_negotiation</a></code>
3558 needs real resources to compare against and evaluate from.</p></div>
3561 <dt><code>SymLinksIfOwnerMatch</code></dt>
3563 <dd>The server will only follow symbolic links for which the
3564 target file or directory is owned by the same user id as the
3567 <div class="note"><h3>Note</h3>
3568 <p>The <code>FollowSymLinks</code> and
3569 <code>SymLinksIfOwnerMatch</code> <code class="directive"><a href="#options">Options</a></code> work only in <code class="directive"><a href="#directory"><Directory></a></code> sections or
3570 <code>.htaccess</code> files.</p>
3572 <p>This option should not be considered a security restriction,
3573 since symlink testing is subject to race conditions that make it
3578 <p>Normally, if multiple <code class="directive">Options</code> could
3579 apply to a directory, then the most specific one is used and
3580 others are ignored; the options are not merged. (See <a href="../sections.html#mergin">how sections are merged</a>.)
3581 However if <em>all</em> the options on the
3582 <code class="directive">Options</code> directive are preceded by a
3583 <code>+</code> or <code>-</code> symbol, the options are
3584 merged. Any options preceded by a <code>+</code> are added to the
3585 options currently in force, and any options preceded by a
3586 <code>-</code> are removed from the options currently in
3589 <div class="note"><h3>Note</h3>
3590 <p>Mixing <code class="directive">Options</code> with a <code>+</code> or
3591 <code>-</code> with those without is not valid syntax and will be
3592 rejected during server startup by the syntax check with an abort.</p>
3595 <p>For example, without any <code>+</code> and <code>-</code> symbols:</p>
3597 <pre class="prettyprint lang-config"><Directory "/web/docs">
3598 Options Indexes FollowSymLinks
3601 <Directory "/web/docs/spec">
3603 </Directory></pre>
3606 <p>then only <code>Includes</code> will be set for the
3607 <code>/web/docs/spec</code> directory. However if the second
3608 <code class="directive">Options</code> directive uses the <code>+</code> and
3609 <code>-</code> symbols:</p>
3611 <pre class="prettyprint lang-config"><Directory "/web/docs">
3612 Options Indexes FollowSymLinks
3615 <Directory "/web/docs/spec">
3616 Options +Includes -Indexes
3617 </Directory></pre>
3620 <p>then the options <code>FollowSymLinks</code> and
3621 <code>Includes</code> are set for the <code>/web/docs/spec</code>
3624 <div class="note"><h3>Note</h3>
3625 <p>Using <code>-IncludesNOEXEC</code> or
3626 <code>-Includes</code> disables server-side includes completely
3627 regardless of the previous setting.</p>
3630 <p>The default in the absence of any other settings is
3631 <code>FollowSymlinks</code>.</p>
3634 <div class="top"><a href="#page-header"><img alt="top" src="../images/up.gif" /></a></div>
3635 <div class="directive-section"><h2><a name="Protocol" id="Protocol">Protocol</a> <a name="protocol" id="protocol">Directive</a></h2>
3636 <table class="directive">
3637 <tr><th><a href="directive-dict.html#Description">Description:</a></th><td>Protocol for a listening socket</td></tr>
3638 <tr><th><a href="directive-dict.html#Syntax">Syntax:</a></th><td><code>Protocol <var>protocol</var></code></td></tr>
3639 <tr><th><a href="directive-dict.html#Context">Context:</a></th><td>server config, virtual host</td></tr>
3640 <tr><th><a href="directive-dict.html#Status">Status:</a></th><td>Core</td></tr>
3641 <tr><th><a href="directive-dict.html#Module">Module:</a></th><td>core</td></tr>
3642 <tr><th><a href="directive-dict.html#Compatibility">Compatibility:</a></th><td>On Windows, only available from Apache 2.3.3 and later.</td></tr>
3644 <p>This directive specifies the protocol used for a specific listening socket.
3645 The protocol is used to determine which module should handle a request and
3646 to apply protocol specific optimizations with the <code class="directive">AcceptFilter</code>
3649 <p>You only need to set the protocol if you are running on non-standard ports;
3650 otherwise, <code>http</code> is assumed for port 80 and <code>https</code>
3653 <p>For example, if you are running <code>https</code> on a non-standard port,
3654 specify the protocol explicitly:</p>
3656 <pre class="prettyprint lang-config">Protocol https</pre>
3659 <p>You can also specify the protocol using the <code class="directive"><a href="../mod/mpm_common.html#listen">Listen</a></code> directive.</p>
3663 <li><code class="directive"><a href="#acceptfilter">AcceptFilter</a></code></li>
3664 <li><code class="directive"><a href="../mod/mpm_common.html#listen">Listen</a></code></li>
3667 <div class="top"><a href="#page-header"><img alt="top" src="../images/up.gif" /></a></div>
3668 <div class="directive-section"><h2><a name="RegisterHttpMethod" id="RegisterHttpMethod">RegisterHttpMethod</a> <a name="registerhttpmethod" id="registerhttpmethod">Directive</a></h2>
3669 <table class="directive">
3670 <tr><th><a href="directive-dict.html#Description">Description:</a></th><td>Register non-standard HTTP methods</td></tr>
3671 <tr><th><a href="directive-dict.html#Syntax">Syntax:</a></th><td><code>RegisterHttpMethod <var>method</var> [<var>method</var> [...]]</code></td></tr>
3672 <tr><th><a href="directive-dict.html#Context">Context:</a></th><td>server config</td></tr>
3673 <tr><th><a href="directive-dict.html#Status">Status:</a></th><td>Core</td></tr>
3674 <tr><th><a href="directive-dict.html#Module">Module:</a></th><td>core</td></tr>
3676 <p>HTTP Methods that are not conforming to the relvant RFCs are normally
3677 rejected by request processing in Apache HTTPD. To avoid this, modules
3678 can register non-standard HTTP methods they support.
3679 The <code class="directive">RegisterHttpMethod</code> allows to register such
3680 methods manually. This can be useful if such methods are forwarded
3681 for external processing, e.g. to a CGI script.</p>
3684 <div class="top"><a href="#page-header"><img alt="top" src="../images/up.gif" /></a></div>
3685 <div class="directive-section"><h2><a name="RLimitCPU" id="RLimitCPU">RLimitCPU</a> <a name="rlimitcpu" id="rlimitcpu">Directive</a></h2>
3686 <table class="directive">
3687 <tr><th><a href="directive-dict.html#Description">Description:</a></th><td>Limits the CPU consumption of processes launched
3688 by Apache httpd children</td></tr>
3689 <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>
3690 <tr><th><a href="directive-dict.html#Default">Default:</a></th><td><code>Unset; uses operating system defaults</code></td></tr>
3691 <tr><th><a href="directive-dict.html#Context">Context:</a></th><td>server config, virtual host, directory, .htaccess</td></tr>
3692 <tr><th><a href="directive-dict.html#Override">Override:</a></th><td>All</td></tr>
3693 <tr><th><a href="directive-dict.html#Status">Status:</a></th><td>Core</td></tr>
3694 <tr><th><a href="directive-dict.html#Module">Module:</a></th><td>core</td></tr>
3696 <p>Takes 1 or 2 parameters. The first parameter sets the soft
3697 resource limit for all processes and the second parameter sets
3698 the maximum resource limit. Either parameter can be a number,
3699 or <code>max</code> to indicate to the server that the limit should
3700 be set to the maximum allowed by the operating system
3701 configuration. Raising the maximum resource limit requires that
3702 the server is running as <code>root</code> or in the initial startup
3705 <p>This applies to processes forked from Apache httpd children
3706 servicing requests, not the Apache httpd children themselves. This
3707 includes CGI scripts and SSI exec commands, but not any
3708 processes forked from the Apache httpd parent, such as piped
3711 <p>CPU resource limits are expressed in seconds per
3716 <li><code class="directive"><a href="#rlimitmem">RLimitMEM</a></code></li>
3717 <li><code class="directive"><a href="#rlimitnproc">RLimitNPROC</a></code></li>
3720 <div class="top"><a href="#page-header"><img alt="top" src="../images/up.gif" /></a></div>
3721 <div class="directive-section"><h2><a name="RLimitMEM" id="RLimitMEM">RLimitMEM</a> <a name="rlimitmem" id="rlimitmem">Directive</a></h2>
3722 <table class="directive">
3723 <tr><th><a href="directive-dict.html#Description">Description:</a></th><td>Limits the memory consumption of processes launched
3724 by Apache httpd children</td></tr>
3725 <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>
3726 <tr><th><a href="directive-dict.html#Default">Default:</a></th><td><code>Unset; uses operating system defaults</code></td></tr>
3727 <tr><th><a href="directive-dict.html#Context">Context:</a></th><td>server config, virtual host, directory, .htaccess</td></tr>
3728 <tr><th><a href="directive-dict.html#Override">Override:</a></th><td>All</td></tr>
3729 <tr><th><a href="directive-dict.html#Status">Status:</a></th><td>Core</td></tr>
3730 <tr><th><a href="directive-dict.html#Module">Module:</a></th><td>core</td></tr>
3732 <p>Takes 1 or 2 parameters. The first parameter sets the soft
3733 resource limit for all processes and the second parameter sets
3734 the maximum resource limit. Either parameter can be a number,
3735 or <code>max</code> to indicate to the server that the limit should
3736 be set to the maximum allowed by the operating system
3737 configuration. Raising the maximum resource limit requires that
3738 the server is running as <code>root</code> or in the initial startup
3741 <p>This applies to processes forked from Apache httpd children
3742 servicing requests, not the Apache httpd children themselves. This
3743 includes CGI scripts and SSI exec commands, but not any
3744 processes forked from the Apache httpd parent, such as piped
3747 <p>Memory resource limits are expressed in bytes per
3752 <li><code class="directive"><a href="#rlimitcpu">RLimitCPU</a></code></li>
3753 <li><code class="directive"><a href="#rlimitnproc">RLimitNPROC</a></code></li>
3756 <div class="top"><a href="#page-header"><img alt="top" src="../images/up.gif" /></a></div>
3757 <div class="directive-section"><h2><a name="RLimitNPROC" id="RLimitNPROC">RLimitNPROC</a> <a name="rlimitnproc" id="rlimitnproc">Directive</a></h2>
3758 <table class="directive">
3759 <tr><th><a href="directive-dict.html#Description">Description:</a></th><td>Limits the number of processes that can be launched by
3760 processes launched by Apache httpd children</td></tr>
3761 <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>
3762 <tr><th><a href="directive-dict.html#Default">Default:</a></th><td><code>Unset; uses operating system defaults</code></td></tr>
3763 <tr><th><a href="directive-dict.html#Context">Context:</a></th><td>server config, virtual host, directory, .htaccess</td></tr>
3764 <tr><th><a href="directive-dict.html#Override">Override:</a></th><td>All</td></tr>
3765 <tr><th><a href="directive-dict.html#Status">Status:</a></th><td>Core</td></tr>
3766 <tr><th><a href="directive-dict.html#Module">Module:</a></th><td>core</td></tr>
3768 <p>Takes 1 or 2 parameters. The first parameter sets the soft
3769 resource limit for all processes, and the second parameter sets
3770 the maximum resource limit. Either parameter can be a number,
3771 or <code>max</code> to indicate to the server that the limit
3772 should be set to the maximum allowed by the operating system
3773 configuration. Raising the maximum resource limit requires that
3774 the server is running as <code>root</code> or in the initial startup
3777 <p>This applies to processes forked from Apache httpd children
3778 servicing requests, not the Apache httpd children themselves. This
3779 includes CGI scripts and SSI exec commands, but not any
3780 processes forked from the Apache httpd parent, such as piped
3783 <p>Process limits control the number of processes per user.</p>
3785 <div class="note"><h3>Note</h3>
3786 <p>If CGI processes are <strong>not</strong> running
3787 under user ids other than the web server user id, this directive
3788 will limit the number of processes that the server itself can
3789 create. Evidence of this situation will be indicated by
3790 <strong><code>cannot fork</code></strong> messages in the
3791 <code>error_log</code>.</p>
3796 <li><code class="directive"><a href="#rlimitmem">RLimitMEM</a></code></li>
3797 <li><code class="directive"><a href="#rlimitcpu">RLimitCPU</a></code></li>
3800 <div class="top"><a href="#page-header"><img alt="top" src="../images/up.gif" /></a></div>
3801 <div class="directive-section"><h2><a name="ScriptInterpreterSource" id="ScriptInterpreterSource">ScriptInterpreterSource</a> <a name="scriptinterpretersource" id="scriptinterpretersource">Directive</a></h2>
3802 <table class="directive">
3803 <tr><th><a href="directive-dict.html#Description">Description:</a></th><td>Technique for locating the interpreter for CGI
3805 <tr><th><a href="directive-dict.html#Syntax">Syntax:</a></th><td><code>ScriptInterpreterSource Registry|Registry-Strict|Script</code></td></tr>
3806 <tr><th><a href="directive-dict.html#Default">Default:</a></th><td><code>ScriptInterpreterSource Script</code></td></tr>
3807 <tr><th><a href="directive-dict.html#Context">Context:</a></th><td>server config, virtual host, directory, .htaccess</td></tr>
3808 <tr><th><a href="directive-dict.html#Override">Override:</a></th><td>FileInfo</td></tr>
3809 <tr><th><a href="directive-dict.html#Status">Status:</a></th><td>Core</td></tr>
3810 <tr><th><a href="directive-dict.html#Module">Module:</a></th><td>core</td></tr>
3811 <tr><th><a href="directive-dict.html#Compatibility">Compatibility:</a></th><td>Win32 only.</td></tr>
3813 <p>This directive is used to control how Apache httpd finds the
3814 interpreter used to run CGI scripts. The default setting is
3815 <code>Script</code>. This causes Apache httpd to use the interpreter pointed to
3816 by the shebang line (first line, starting with <code>#!</code>) in the
3817 script. On Win32 systems this line usually looks like:</p>
3819 <pre class="prettyprint lang-perl">#!C:/Perl/bin/perl.exe</pre>
3822 <p>or, if <code>perl</code> is in the <code>PATH</code>, simply:</p>
3824 <pre class="prettyprint lang-perl">#!perl</pre>
3827 <p>Setting <code>ScriptInterpreterSource Registry</code> will
3828 cause the Windows Registry tree <code>HKEY_CLASSES_ROOT</code> to be
3829 searched using the script file extension (e.g., <code>.pl</code>) as a
3830 search key. The command defined by the registry subkey
3831 <code>Shell\ExecCGI\Command</code> or, if it does not exist, by the subkey
3832 <code>Shell\Open\Command</code> is used to open the script file. If the
3833 registry keys cannot be found, Apache httpd falls back to the behavior of the
3834 <code>Script</code> option.</p>
3836 <div class="warning"><h3>Security</h3>
3837 <p>Be careful when using <code>ScriptInterpreterSource
3838 Registry</code> with <code class="directive"><a href="../mod/mod_alias.html#scriptalias">ScriptAlias</a></code>'ed directories, because
3839 Apache httpd will try to execute <strong>every</strong> file within this
3840 directory. The <code>Registry</code> setting may cause undesired
3841 program calls on files which are typically not executed. For
3842 example, the default open command on <code>.htm</code> files on
3843 most Windows systems will execute Microsoft Internet Explorer, so
3844 any HTTP request for an <code>.htm</code> file existing within the
3845 script directory would start the browser in the background on the
3846 server. This is a good way to crash your system within a minute or
3850 <p>The option <code>Registry-Strict</code> which is new in Apache HTTP Server
3851 2.0 does the same thing as <code>Registry</code> but uses only the
3852 subkey <code>Shell\ExecCGI\Command</code>. The
3853 <code>ExecCGI</code> key is not a common one. It must be
3854 configured manually in the windows registry and hence prevents
3855 accidental program calls on your system.</p>
3858 <div class="top"><a href="#page-header"><img alt="top" src="../images/up.gif" /></a></div>
3859 <div class="directive-section"><h2><a name="SeeRequestTail" id="SeeRequestTail">SeeRequestTail</a> <a name="seerequesttail" id="seerequesttail">Directive</a></h2>
3860 <table class="directive">
3861 <tr><th><a href="directive-dict.html#Description">Description:</a></th><td>Determine if mod_status displays the first 63 characters
3862 of a request or the last 63, assuming the request itself is greater than
3864 <tr><th><a href="directive-dict.html#Syntax">Syntax:</a></th><td><code>SeeRequestTail On|Off</code></td></tr>
3865 <tr><th><a href="directive-dict.html#Default">Default:</a></th><td><code>SeeRequestTail Off</code></td></tr>
3866 <tr><th><a href="directive-dict.html#Context">Context:</a></th><td>server config</td></tr>
3867 <tr><th><a href="directive-dict.html#Status">Status:</a></th><td>Core</td></tr>
3868 <tr><th><a href="directive-dict.html#Module">Module:</a></th><td>core</td></tr>
3870 <p>mod_status with <code>ExtendedStatus On</code>
3871 displays the actual request being handled.
3872 For historical purposes, only 63 characters of the request
3873 are actually stored for display purposes. This directive
3874 controls whether the 1st 63 characters are stored (the previous
3875 behavior and the default) or if the last 63 characters are. This
3876 is only applicable, of course, if the length of the request is
3877 64 characters or greater.</p>
3879 <p>If Apache httpd is handling <code>GET /disk1/storage/apache/htdocs/images/imagestore1/food/apples.jpg HTTP/1.1</code> mod_status displays as follows:
3882 <table class="bordered">
3884 <th>Off (default)</th>
3885 <td>GET /disk1/storage/apache/htdocs/images/imagestore1/food/apples</td>
3889 <td>orage/apache/htdocs/images/imagestore1/food/apples.jpg HTTP/1.1</td>
3895 <div class="top"><a href="#page-header"><img alt="top" src="../images/up.gif" /></a></div>
3896 <div class="directive-section"><h2><a name="ServerAdmin" id="ServerAdmin">ServerAdmin</a> <a name="serveradmin" id="serveradmin">Directive</a></h2>
3897 <table class="directive">
3898 <tr><th><a href="directive-dict.html#Description">Description:</a></th><td>Email address that the server includes in error
3899 messages sent to the client</td></tr>
3900 <tr><th><a href="directive-dict.html#Syntax">Syntax:</a></th><td><code>ServerAdmin <var>email-address</var>|<var>URL</var></code></td></tr>
3901 <tr><th><a href="directive-dict.html#Context">Context:</a></th><td>server config, virtual host</td></tr>
3902 <tr><th><a href="directive-dict.html#Status">Status:</a></th><td>Core</td></tr>
3903 <tr><th><a href="directive-dict.html#Module">Module:</a></th><td>core</td></tr>
3905 <p>The <code class="directive">ServerAdmin</code> sets the contact address
3906 that the server includes in any error messages it returns to the
3907 client. If the <code>httpd</code> doesn't recognize the supplied argument
3909 assumes, that it's an <var>email-address</var> and prepends it with
3910 <code>mailto:</code> in hyperlink targets. However, it's recommended to
3911 actually use an email address, since there are a lot of CGI scripts that
3912 make that assumption. If you want to use an URL, it should point to another
3913 server under your control. Otherwise users may not be able to contact you in
3916 <p>It may be worth setting up a dedicated address for this, e.g.</p>
3918 <pre class="prettyprint lang-config">ServerAdmin www-admin@foo.example.com</pre>
3920 <p>as users do not always mention that they are talking about the
3924 <div class="top"><a href="#page-header"><img alt="top" src="../images/up.gif" /></a></div>
3925 <div class="directive-section"><h2><a name="ServerAlias" id="ServerAlias">ServerAlias</a> <a name="serveralias" id="serveralias">Directive</a></h2>
3926 <table class="directive">
3927 <tr><th><a href="directive-dict.html#Description">Description:</a></th><td>Alternate names for a host used when matching requests
3928 to name-virtual hosts</td></tr>
3929 <tr><th><a href="directive-dict.html#Syntax">Syntax:</a></th><td><code>ServerAlias <var>hostname</var> [<var>hostname</var>] ...</code></td></tr>
3930 <tr><th><a href="directive-dict.html#Context">Context:</a></th><td>virtual host</td></tr>
3931 <tr><th><a href="directive-dict.html#Status">Status:</a></th><td>Core</td></tr>
3932 <tr><th><a href="directive-dict.html#Module">Module:</a></th><td>core</td></tr>
3934 <p>The <code class="directive">ServerAlias</code> directive sets the
3935 alternate names for a host, for use with <a href="../vhosts/name-based.html">name-based virtual hosts</a>. The
3936 <code class="directive">ServerAlias</code> may include wildcards, if appropriate.</p>
3938 <pre class="prettyprint lang-config"><VirtualHost *:80>
3939 ServerName server.example.com
3940 ServerAlias server server2.example.com server2
3941 ServerAlias *.example.com
3942 UseCanonicalName Off
3944 </VirtualHost></pre>
3947 <p>Name-based virtual hosts for the best-matching set of <code class="directive"><a href="#virtualhost"><virtualhost></a></code>s are processed
3948 in the order they appear in the configuration. The first matching <code class="directive"><a href="#servername">ServerName</a></code> or <code class="directive"><a href="#serveralias">ServerAlias</a></code> is used, with no different precedence for wildcards
3949 (nor for ServerName vs. ServerAlias). </p>
3951 <p>The complete list of names in the <code class="directive">VirtualHost</code>
3952 directive are treated just like a (non wildcard)
3953 <code class="directive">ServerAlias</code>.</p>
3958 <li><code class="directive"><a href="#usecanonicalname">UseCanonicalName</a></code></li>
3959 <li><a href="../vhosts/">Apache HTTP Server Virtual Host documentation</a></li>
3962 <div class="top"><a href="#page-header"><img alt="top" src="../images/up.gif" /></a></div>
3963 <div class="directive-section"><h2><a name="ServerName" id="ServerName">ServerName</a> <a name="servername" id="servername">Directive</a></h2>
3964 <table class="directive">
3965 <tr><th><a href="directive-dict.html#Description">Description:</a></th><td>Hostname and port that the server uses to identify
3967 <tr><th><a href="directive-dict.html#Syntax">Syntax:</a></th><td><code>ServerName [<var>scheme</var>://]<var>fully-qualified-domain-name</var>[:<var>port</var>]</code></td></tr>
3968 <tr><th><a href="directive-dict.html#Context">Context:</a></th><td>server config, virtual host</td></tr>
3969 <tr><th><a href="directive-dict.html#Status">Status:</a></th><td>Core</td></tr>
3970 <tr><th><a href="directive-dict.html#Module">Module:</a></th><td>core</td></tr>
3972 <p>The <code class="directive">ServerName</code> directive sets the
3973 request scheme, hostname and
3974 port that the server uses to identify itself. This is used when
3975 creating redirection URLs.</p>
3977 <p>Additionally, <code class="directive">ServerName</code> is used (possibly
3978 in conjunction with <code class="directive">ServerAlias</code>) to uniquely
3979 identify a virtual host, when using <a href="../vhosts/name-based.html">name-based virtual hosts</a>.</p>
3981 <p>For example, if the name of the
3982 machine hosting the web server is <code>simple.example.com</code>,
3983 but the machine also has the DNS alias <code>www.example.com</code>
3984 and you wish the web server to be so identified, the following
3985 directive should be used:</p>
3987 <pre class="prettyprint lang-config">ServerName www.example.com</pre>
3990 <p>The <code class="directive">ServerName</code> directive
3991 may appear anywhere within the definition of a server. However,
3992 each appearance overrides the previous appearance (within that
3995 <p>If no <code class="directive">ServerName</code> is specified, then the
3996 server attempts to deduce the client visible hostname by performing a
3997 reverse lookup on an IP address of the systems hostname.</p>
3999 <p>If no port is specified in the
4000 <code class="directive">ServerName</code>, then the server will use the
4001 port from the incoming request. For optimal reliability and
4002 predictability, you should specify an explicit hostname and port
4003 using the <code class="directive">ServerName</code> directive.</p>
4005 <p>If you are using <a href="../vhosts/name-based.html">name-based virtual hosts</a>,
4006 the <code class="directive">ServerName</code> inside a
4007 <code class="directive"><a href="#virtualhost"><VirtualHost></a></code>
4008 section specifies what hostname must appear in the request's
4009 <code>Host:</code> header to match this virtual host.</p>
4011 <p>Sometimes, the server runs behind a device that processes SSL,
4012 such as a reverse proxy, load balancer or SSL offload
4013 appliance. When this is the case, specify the
4014 <code>https://</code> scheme and the port number to which the
4015 clients connect in the <code class="directive">ServerName</code> directive
4016 to make sure that the server generates the correct
4017 self-referential URLs.
4020 <p>See the description of the
4021 <code class="directive"><a href="#usecanonicalname">UseCanonicalName</a></code> and
4022 <code class="directive"><a href="#usecanonicalphysicalport">UseCanonicalPhysicalPort</a></code> directives for
4023 settings which determine whether self-referential URLs (e.g., by the
4024 <code class="module"><a href="../mod/mod_dir.html">mod_dir</a></code> module) will refer to the
4025 specified port, or to the port number given in the client's request.
4028 <div class="warning">
4029 <p>Failure to set <code class="directive">ServerName</code> to a name that
4030 your server can resolve to an IP address will result in a startup
4031 warning. <code>httpd</code> will then use whatever hostname it can
4032 determine, using the system's <code>hostname</code> command. This
4033 will almost never be the hostname you actually want.</p>
4034 <div class="example"><p><code>
4035 httpd: Could not reliably determine the server's fully qualified domain name, using rocinante.local for ServerName
4042 <li><a href="../dns-caveats.html">Issues Regarding DNS and
4043 Apache HTTP Server</a></li>
4044 <li><a href="../vhosts/">Apache HTTP Server virtual host
4045 documentation</a></li>
4046 <li><code class="directive"><a href="#usecanonicalname">UseCanonicalName</a></code></li>
4047 <li><code class="directive"><a href="#usecanonicalphysicalport">UseCanonicalPhysicalPort</a></code></li>
4048 <li><code class="directive"><a href="#serveralias">ServerAlias</a></code></li>
4051 <div class="top"><a href="#page-header"><img alt="top" src="../images/up.gif" /></a></div>
4052 <div class="directive-section"><h2><a name="ServerPath" id="ServerPath">ServerPath</a> <a name="serverpath" id="serverpath">Directive</a></h2>
4053 <table class="directive">
4054 <tr><th><a href="directive-dict.html#Description">Description:</a></th><td>Legacy URL pathname for a name-based virtual host that
4055 is accessed by an incompatible browser</td></tr>
4056 <tr><th><a href="directive-dict.html#Syntax">Syntax:</a></th><td><code>ServerPath <var>URL-path</var></code></td></tr>
4057 <tr><th><a href="directive-dict.html#Context">Context:</a></th><td>virtual host</td></tr>
4058 <tr><th><a href="directive-dict.html#Status">Status:</a></th><td>Core</td></tr>
4059 <tr><th><a href="directive-dict.html#Module">Module:</a></th><td>core</td></tr>
4061 <p>The <code class="directive">ServerPath</code> directive sets the legacy
4062 URL pathname for a host, for use with <a href="../vhosts/">name-based virtual hosts</a>.</p>
4066 <li><a href="../vhosts/">Apache HTTP Server Virtual Host documentation</a></li>
4069 <div class="top"><a href="#page-header"><img alt="top" src="../images/up.gif" /></a></div>
4070 <div class="directive-section"><h2><a name="ServerRoot" id="ServerRoot">ServerRoot</a> <a name="serverroot" id="serverroot">Directive</a></h2>
4071 <table class="directive">
4072 <tr><th><a href="directive-dict.html#Description">Description:</a></th><td>Base directory for the server installation</td></tr>
4073 <tr><th><a href="directive-dict.html#Syntax">Syntax:</a></th><td><code>ServerRoot <var>directory-path</var></code></td></tr>
4074 <tr><th><a href="directive-dict.html#Default">Default:</a></th><td><code>ServerRoot /usr/local/apache</code></td></tr>
4075 <tr><th><a href="directive-dict.html#Context">Context:</a></th><td>server config</td></tr>
4076 <tr><th><a href="directive-dict.html#Status">Status:</a></th><td>Core</td></tr>
4077 <tr><th><a href="directive-dict.html#Module">Module:</a></th><td>core</td></tr>
4079 <p>The <code class="directive">ServerRoot</code> directive sets the
4080 directory in which the server lives. Typically it will contain the
4081 subdirectories <code>conf/</code> and <code>logs/</code>. Relative
4082 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
4083 relative to this directory.</p>
4085 <pre class="prettyprint lang-config">ServerRoot "/home/httpd"</pre>
4088 <p>The default location of <code class="directive">ServerRoot</code> may be
4089 modified by using the <code>--prefix</code> argument to
4090 <a href="../programs/configure.html"><code>configure</code></a>, and
4091 most third-party distributions of the server have a different
4092 default location from the one listed above.</p>
4097 <li><a href="../invoking.html">the <code>-d</code>
4098 option to <code>httpd</code></a></li>
4099 <li><a href="../misc/security_tips.html#serverroot">the
4100 security tips</a> for information on how to properly set
4101 permissions on the <code class="directive">ServerRoot</code></li>
4104 <div class="top"><a href="#page-header"><img alt="top" src="../images/up.gif" /></a></div>
4105 <div class="directive-section"><h2><a name="ServerSignature" id="ServerSignature">ServerSignature</a> <a name="serversignature" id="serversignature">Directive</a></h2>
4106 <table class="directive">
4107 <tr><th><a href="directive-dict.html#Description">Description:</a></th><td>Configures the footer on server-generated documents</td></tr>
4108 <tr><th><a href="directive-dict.html#Syntax">Syntax:</a></th><td><code>ServerSignature On|Off|EMail</code></td></tr>
4109 <tr><th><a href="directive-dict.html#Default">Default:</a></th><td><code>ServerSignature Off</code></td></tr>
4110 <tr><th><a href="directive-dict.html#Context">Context:</a></th><td>server config, virtual host, directory, .htaccess</td></tr>
4111 <tr><th><a href="directive-dict.html#Override">Override:</a></th><td>All</td></tr>
4112 <tr><th><a href="directive-dict.html#Status">Status:</a></th><td>Core</td></tr>
4113 <tr><th><a href="directive-dict.html#Module">Module:</a></th><td>core</td></tr>
4115 <p>The <code class="directive">ServerSignature</code> directive allows the
4116 configuration of a trailing footer line under server-generated
4117 documents (error messages, <code class="module"><a href="../mod/mod_proxy.html">mod_proxy</a></code> ftp directory
4118 listings, <code class="module"><a href="../mod/mod_info.html">mod_info</a></code> output, ...). The reason why you
4119 would want to enable such a footer line is that in a chain of proxies,
4120 the user often has no possibility to tell which of the chained servers
4121 actually produced a returned error message.</p>
4123 <p>The <code>Off</code>
4124 setting, which is the default, suppresses the footer line (and is
4125 therefore compatible with the behavior of Apache-1.2 and
4126 below). The <code>On</code> setting simply adds a line with the
4127 server version number and <code class="directive"><a href="#servername">ServerName</a></code> of the serving virtual host,
4128 and the <code>EMail</code> setting additionally creates a
4129 "mailto:" reference to the <code class="directive"><a href="#serveradmin">ServerAdmin</a></code> of the referenced
4132 <p>After version 2.0.44, the details of the server version number
4133 presented are controlled by the <code class="directive"><a href="#servertokens">ServerTokens</a></code> directive.</p>
4137 <li><code class="directive"><a href="#servertokens">ServerTokens</a></code></li>
4140 <div class="top"><a href="#page-header"><img alt="top" src="../images/up.gif" /></a></div>
4141 <div class="directive-section"><h2><a name="ServerTokens" id="ServerTokens">ServerTokens</a> <a name="servertokens" id="servertokens">Directive</a></h2>
4142 <table class="directive">
4143 <tr><th><a href="directive-dict.html#Description">Description:</a></th><td>Configures the <code>Server</code> HTTP response
4145 <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>
4146 <tr><th><a href="directive-dict.html#Default">Default:</a></th><td><code>ServerTokens Full</code></td></tr>
4147 <tr><th><a href="directive-dict.html#Context">Context:</a></th><td>server config</td></tr>
4148 <tr><th><a href="directive-dict.html#Status">Status:</a></th><td>Core</td></tr>
4149 <tr><th><a href="directive-dict.html#Module">Module:</a></th><td>core</td></tr>
4151 <p>This directive controls whether <code>Server</code> response
4152 header field which is sent back to clients includes a
4153 description of the generic OS-type of the server as well as
4154 information about compiled-in modules.</p>
4157 <dt><code>ServerTokens Full</code> (or not specified)</dt>
4159 <dd>Server sends (<em>e.g.</em>): <code>Server: Apache/2.4.2
4160 (Unix) PHP/4.2.2 MyMod/1.2</code></dd>
4162 <dt><code>ServerTokens Prod[uctOnly]</code></dt>
4164 <dd>Server sends (<em>e.g.</em>): <code>Server:
4167 <dt><code>ServerTokens Major</code></dt>
4169 <dd>Server sends (<em>e.g.</em>): <code>Server:
4170 Apache/2</code></dd>
4172 <dt><code>ServerTokens Minor</code></dt>
4174 <dd>Server sends (<em>e.g.</em>): <code>Server:
4175 Apache/2.4</code></dd>
4177 <dt><code>ServerTokens Min[imal]</code></dt>
4179 <dd>Server sends (<em>e.g.</em>): <code>Server:
4180 Apache/2.4.2</code></dd>
4182 <dt><code>ServerTokens OS</code></dt>
4184 <dd>Server sends (<em>e.g.</em>): <code>Server: Apache/2.4.2
4189 <p>This setting applies to the entire server, and cannot be
4190 enabled or disabled on a virtualhost-by-virtualhost basis.</p>
4192 <p>After version 2.0.44, this directive also controls the
4193 information presented by the <code class="directive"><a href="#serversignature">ServerSignature</a></code> directive.</p>
4195 <div class="note">Setting <code class="directive">ServerTokens</code> to less than
4196 <code>minimal</code> is not recommended because it makes it more
4197 difficult to debug interoperational problems. Also note that
4198 disabling the Server: header does nothing at all to make your
4199 server more secure. The idea of "security through obscurity"
4200 is a myth and leads to a false sense of safety.</div>
4204 <li><code class="directive"><a href="#serversignature">ServerSignature</a></code></li>
4207 <div class="top"><a href="#page-header"><img alt="top" src="../images/up.gif" /></a></div>
4208 <div class="directive-section"><h2><a name="SetHandler" id="SetHandler">SetHandler</a> <a name="sethandler" id="sethandler">Directive</a></h2>
4209 <table class="directive">
4210 <tr><th><a href="directive-dict.html#Description">Description:</a></th><td>Forces all matching files to be processed by a
4212 <tr><th><a href="directive-dict.html#Syntax">Syntax:</a></th><td><code>SetHandler <var>handler-name</var>|None</code></td></tr>
4213 <tr><th><a href="directive-dict.html#Context">Context:</a></th><td>server config, virtual host, directory, .htaccess</td></tr>
4214 <tr><th><a href="directive-dict.html#Override">Override:</a></th><td>FileInfo</td></tr>
4215 <tr><th><a href="directive-dict.html#Status">Status:</a></th><td>Core</td></tr>
4216 <tr><th><a href="directive-dict.html#Module">Module:</a></th><td>core</td></tr>
4218 <p>When placed into an <code>.htaccess</code> file or a
4219 <code class="directive"><a href="#directory"><Directory></a></code> or
4220 <code class="directive"><a href="#location"><Location></a></code>
4221 section, this directive forces all matching files to be parsed
4222 through the <a href="../handler.html">handler</a> given by
4223 <var>handler-name</var>. For example, if you had a directory you
4224 wanted to be parsed entirely as imagemap rule files, regardless
4225 of extension, you might put the following into an
4226 <code>.htaccess</code> file in that directory:</p>
4228 <pre class="prettyprint lang-config">SetHandler imap-file</pre>
4231 <p>Another example: if you wanted to have the server display a
4232 status report whenever a URL of
4233 <code>http://servername/status</code> was called, you might put
4234 the following into <code>httpd.conf</code>:</p>
4236 <pre class="prettyprint lang-config"><Location "/status">
4237 SetHandler server-status
4238 </Location></pre>
4241 <p>You could also use this directive to configure a particular
4242 handler for files with a particular file extension. For example:</p>
4244 <pre class="prettyprint lang-config"><FilesMatch "\.php$">
4245 SetHandler application/x-httpd-php
4246 </FilesMatch></pre>
4249 <p>You can override an earlier defined <code class="directive">SetHandler</code>
4250 directive by using the value <code>None</code>.</p>
4252 <div class="note"><h3>Note</h3>
4253 <p>Because <code class="directive">SetHandler</code> overrides default handlers,
4254 normal behavior such as handling of URLs ending in a slash (/) as
4255 directories or index files is suppressed.</p></div>
4259 <li><code class="directive"><a href="../mod/mod_mime.html#addhandler">AddHandler</a></code></li>
4262 <div class="top"><a href="#page-header"><img alt="top" src="../images/up.gif" /></a></div>
4263 <div class="directive-section"><h2><a name="SetInputFilter" id="SetInputFilter">SetInputFilter</a> <a name="setinputfilter" id="setinputfilter">Directive</a></h2>
4264 <table class="directive">
4265 <tr><th><a href="directive-dict.html#Description">Description:</a></th><td>Sets the filters that will process client requests and POST
4267 <tr><th><a href="directive-dict.html#Syntax">Syntax:</a></th><td><code>SetInputFilter <var>filter</var>[;<var>filter</var>...]</code></td></tr>
4268 <tr><th><a href="directive-dict.html#Context">Context:</a></th><td>server config, virtual host, directory, .htaccess</td></tr>
4269 <tr><th><a href="directive-dict.html#Override">Override:</a></th><td>FileInfo</td></tr>
4270 <tr><th><a href="directive-dict.html#Status">Status:</a></th><td>Core</td></tr>
4271 <tr><th><a href="directive-dict.html#Module">Module:</a></th><td>core</td></tr>
4273 <p>The <code class="directive">SetInputFilter</code> directive sets the
4274 filter or filters which will process client requests and POST
4275 input when they are received by the server. This is in addition to
4276 any filters defined elsewhere, including the
4277 <code class="directive"><a href="../mod/mod_mime.html#addinputfilter">AddInputFilter</a></code>
4280 <p>If more than one filter is specified, they must be separated
4281 by semicolons in the order in which they should process the
4286 <li><a href="../filter.html">Filters</a> documentation</li>
4289 <div class="top"><a href="#page-header"><img alt="top" src="../images/up.gif" /></a></div>
4290 <div class="directive-section"><h2><a name="SetOutputFilter" id="SetOutputFilter">SetOutputFilter</a> <a name="setoutputfilter" id="setoutputfilter">Directive</a></h2>
4291 <table class="directive">
4292 <tr><th><a href="directive-dict.html#Description">Description:</a></th><td>Sets the filters that will process responses from the
4294 <tr><th><a href="directive-dict.html#Syntax">Syntax:</a></th><td><code>SetOutputFilter <var>filter</var>[;<var>filter</var>...]</code></td></tr>
4295 <tr><th><a href="directive-dict.html#Context">Context:</a></th><td>server config, virtual host, directory, .htaccess</td></tr>
4296 <tr><th><a href="directive-dict.html#Override">Override:</a></th><td>FileInfo</td></tr>
4297 <tr><th><a href="directive-dict.html#Status">Status:</a></th><td>Core</td></tr>
4298 <tr><th><a href="directive-dict.html#Module">Module:</a></th><td>core</td></tr>
4300 <p>The <code class="directive">SetOutputFilter</code> directive sets the filters
4301 which will process responses from the server before they are
4302 sent to the client. This is in addition to any filters defined
4303 elsewhere, including the
4304 <code class="directive"><a href="../mod/mod_mime.html#addoutputfilter">AddOutputFilter</a></code>
4307 <p>For example, the following configuration will process all files
4308 in the <code>/www/data/</code> directory for server-side
4311 <pre class="prettyprint lang-config"><Directory "/www/data/">
4312 SetOutputFilter INCLUDES
4313 </Directory></pre>
4316 <p>If more than one filter is specified, they must be separated
4317 by semicolons in the order in which they should process the
4322 <li><a href="../filter.html">Filters</a> documentation</li>
4325 <div class="top"><a href="#page-header"><img alt="top" src="../images/up.gif" /></a></div>
4326 <div class="directive-section"><h2><a name="TimeOut" id="TimeOut">TimeOut</a> <a name="timeout" id="timeout">Directive</a></h2>
4327 <table class="directive">
4328 <tr><th><a href="directive-dict.html#Description">Description:</a></th><td>Amount of time the server will wait for
4329 certain events before failing a request</td></tr>
4330 <tr><th><a href="directive-dict.html#Syntax">Syntax:</a></th><td><code>TimeOut <var>seconds</var></code></td></tr>
4331 <tr><th><a href="directive-dict.html#Default">Default:</a></th><td><code>TimeOut 60</code></td></tr>
4332 <tr><th><a href="directive-dict.html#Context">Context:</a></th><td>server config, virtual host</td></tr>
4333 <tr><th><a href="directive-dict.html#Status">Status:</a></th><td>Core</td></tr>
4334 <tr><th><a href="directive-dict.html#Module">Module:</a></th><td>core</td></tr>
4336 <p>The <code class="directive">TimeOut</code> directive defines the length
4337 of time Apache httpd will wait for I/O in various circumstances:</p>
4340 <li>When reading data from the client, the length of time to
4341 wait for a TCP packet to arrive if the read buffer is
4344 <li>When writing data to the client, the length of time to wait
4345 for an acknowledgement of a packet if the send buffer is
4348 <li>In <code class="module"><a href="../mod/mod_cgi.html">mod_cgi</a></code> and <code class="module"><a href="../mod/mod_cgid.html">mod_cgid</a></code>,
4349 the length of time to wait for output from a CGI script.</li>
4351 <li>In <code class="module"><a href="../mod/mod_ext_filter.html">mod_ext_filter</a></code>, the length of time to
4352 wait for output from a filtering process.</li>
4354 <li>In <code class="module"><a href="../mod/mod_proxy.html">mod_proxy</a></code>, the default timeout value if
4355 <code class="directive"><a href="../mod/mod_proxy.html#proxytimeout">ProxyTimeout</a></code> is not
4361 <div class="top"><a href="#page-header"><img alt="top" src="../images/up.gif" /></a></div>
4362 <div class="directive-section"><h2><a name="TraceEnable" id="TraceEnable">TraceEnable</a> <a name="traceenable" id="traceenable">Directive</a></h2>
4363 <table class="directive">
4364 <tr><th><a href="directive-dict.html#Description">Description:</a></th><td>Determines the behavior on <code>TRACE</code> requests</td></tr>
4365 <tr><th><a href="directive-dict.html#Syntax">Syntax:</a></th><td><code>TraceEnable <var>[on|off|extended]</var></code></td></tr>
4366 <tr><th><a href="directive-dict.html#Default">Default:</a></th><td><code>TraceEnable on</code></td></tr>
4367 <tr><th><a href="directive-dict.html#Context">Context:</a></th><td>server config, virtual host</td></tr>
4368 <tr><th><a href="directive-dict.html#Status">Status:</a></th><td>Core</td></tr>
4369 <tr><th><a href="directive-dict.html#Module">Module:</a></th><td>core</td></tr>
4371 <p>This directive overrides the behavior of <code>TRACE</code> for both
4372 the core server and <code class="module"><a href="../mod/mod_proxy.html">mod_proxy</a></code>. The default
4373 <code>TraceEnable on</code> permits <code>TRACE</code> requests per
4374 RFC 2616, which disallows any request body to accompany the request.
4375 <code>TraceEnable off</code> causes the core server and
4376 <code class="module"><a href="../mod/mod_proxy.html">mod_proxy</a></code> to return a <code>405</code> (Method not
4377 allowed) error to the client.</p>
4379 <p>Finally, for testing and diagnostic purposes only, request
4380 bodies may be allowed using the non-compliant <code>TraceEnable
4381 extended</code> directive. The core (as an origin server) will
4382 restrict the request body to 64k (plus 8k for chunk headers if
4383 <code>Transfer-Encoding: chunked</code> is used). The core will
4384 reflect the full headers and all chunk headers with the response
4385 body. As a proxy server, the request body is not restricted to 64k.</p>
4387 <div class="note"><h3>Note</h3>
4388 <p>Despite claims to the contrary, <code>TRACE</code> is not
4389 a security vulnerability, and there is no viable reason for
4390 it to be disabled. Doing so necessarily makes your server
4395 <div class="top"><a href="#page-header"><img alt="top" src="../images/up.gif" /></a></div>
4396 <div class="directive-section"><h2><a name="UnDefine" id="UnDefine">UnDefine</a> <a name="undefine" id="undefine">Directive</a></h2>
4397 <table class="directive">
4398 <tr><th><a href="directive-dict.html#Description">Description:</a></th><td>Undefine the existence of a variable</td></tr>
4399 <tr><th><a href="directive-dict.html#Syntax">Syntax:</a></th><td><code>UnDefine <var>parameter-name</var></code></td></tr>
4400 <tr><th><a href="directive-dict.html#Context">Context:</a></th><td>server config, virtual host</td></tr>
4401 <tr><th><a href="directive-dict.html#Status">Status:</a></th><td>Core</td></tr>
4402 <tr><th><a href="directive-dict.html#Module">Module:</a></th><td>core</td></tr>
4404 <p>Undoes the effect of a <code class="directive"><a href="#define">Define</a></code> or
4405 of passing a <code>-D</code> argument to <code class="program"><a href="../programs/httpd.html">httpd</a></code>.</p>
4406 <p>This directive can be used to toggle the use of <code class="directive"><a href="#ifdefine"><IfDefine></a></code> sections without needing to alter
4407 <code>-D</code> arguments in any startup scripts.</p>
4408 <p>While this directive is supported in virtual host context,
4409 the changes it makes are visible to any later configuration
4410 directives, beyond any enclosing virtual host.</p>
4413 <div class="top"><a href="#page-header"><img alt="top" src="../images/up.gif" /></a></div>
4414 <div class="directive-section"><h2><a name="UseCanonicalName" id="UseCanonicalName">UseCanonicalName</a> <a name="usecanonicalname" id="usecanonicalname">Directive</a></h2>
4415 <table class="directive">
4416 <tr><th><a href="directive-dict.html#Description">Description:</a></th><td>Configures how the server determines its own name and
4418 <tr><th><a href="directive-dict.html#Syntax">Syntax:</a></th><td><code>UseCanonicalName On|Off|DNS</code></td></tr>
4419 <tr><th><a href="directive-dict.html#Default">Default:</a></th><td><code>UseCanonicalName Off</code></td></tr>
4420 <tr><th><a href="directive-dict.html#Context">Context:</a></th><td>server config, virtual host, directory</td></tr>
4421 <tr><th><a href="directive-dict.html#Status">Status:</a></th><td>Core</td></tr>
4422 <tr><th><a href="directive-dict.html#Module">Module:</a></th><td>core</td></tr>
4424 <p>In many situations Apache httpd must construct a <em>self-referential</em>
4425 URL -- that is, a URL that refers back to the same server. With
4426 <code>UseCanonicalName On</code> Apache httpd will use the hostname and port
4427 specified in the <code class="directive"><a href="#servername">ServerName</a></code>
4428 directive to construct the canonical name for the server. This name
4429 is used in all self-referential URLs, and for the values of
4430 <code>SERVER_NAME</code> and <code>SERVER_PORT</code> in CGIs.</p>
4432 <p>With <code>UseCanonicalName Off</code> Apache httpd will form
4433 self-referential URLs using the hostname and port supplied by
4434 the client if any are supplied (otherwise it will use the
4435 canonical name, as defined above). These values are the same
4436 that are used to implement <a href="../vhosts/name-based.html">name-based virtual hosts</a>
4437 and are available with the same clients. The CGI variables
4438 <code>SERVER_NAME</code> and <code>SERVER_PORT</code> will be
4439 constructed from the client supplied values as well.</p>
4441 <p>An example where this may be useful is on an intranet server
4442 where you have users connecting to the machine using short
4443 names such as <code>www</code>. You'll notice that if the users
4444 type a shortname and a URL which is a directory, such as
4445 <code>http://www/splat</code>, <em>without the trailing
4446 slash</em>, then Apache httpd will redirect them to
4447 <code>http://www.example.com/splat/</code>. If you have
4448 authentication enabled, this will cause the user to have to
4449 authenticate twice (once for <code>www</code> and once again
4450 for <code>www.example.com</code> -- see <a href="http://wiki.apache.org/httpd/FAQ#Why_does_Apache_ask_for_my_password_twice_before_serving_a_file.3F">
4451 the FAQ on this subject for more information</a>). But if
4452 <code class="directive">UseCanonicalName</code> is set <code>Off</code>, then
4453 Apache httpd will redirect to <code>http://www/splat/</code>.</p>
4455 <p>There is a third option, <code>UseCanonicalName DNS</code>,
4456 which is intended for use with mass IP-based virtual hosting to
4457 support ancient clients that do not provide a
4458 <code>Host:</code> header. With this option, Apache httpd does a
4459 reverse DNS lookup on the server IP address that the client
4460 connected to in order to work out self-referential URLs.</p>
4462 <div class="warning"><h3>Warning</h3>
4463 <p>If CGIs make assumptions about the values of <code>SERVER_NAME</code>,
4464 they may be broken by this option. The client is essentially free
4465 to give whatever value they want as a hostname. But if the CGI is
4466 only using <code>SERVER_NAME</code> to construct self-referential URLs,
4467 then it should be just fine.</p>
4472 <li><code class="directive"><a href="#usecanonicalphysicalport">UseCanonicalPhysicalPort</a></code></li>
4473 <li><code class="directive"><a href="#servername">ServerName</a></code></li>
4474 <li><code class="directive"><a href="../mod/mpm_common.html#listen">Listen</a></code></li>
4477 <div class="top"><a href="#page-header"><img alt="top" src="../images/up.gif" /></a></div>
4478 <div class="directive-section"><h2><a name="UseCanonicalPhysicalPort" id="UseCanonicalPhysicalPort">UseCanonicalPhysicalPort</a> <a name="usecanonicalphysicalport" id="usecanonicalphysicalport">Directive</a></h2>
4479 <table class="directive">
4480 <tr><th><a href="directive-dict.html#Description">Description:</a></th><td>Configures how the server determines its own port</td></tr>
4481 <tr><th><a href="directive-dict.html#Syntax">Syntax:</a></th><td><code>UseCanonicalPhysicalPort On|Off</code></td></tr>
4482 <tr><th><a href="directive-dict.html#Default">Default:</a></th><td><code>UseCanonicalPhysicalPort Off</code></td></tr>
4483 <tr><th><a href="directive-dict.html#Context">Context:</a></th><td>server config, virtual host, directory</td></tr>
4484 <tr><th><a href="directive-dict.html#Status">Status:</a></th><td>Core</td></tr>
4485 <tr><th><a href="directive-dict.html#Module">Module:</a></th><td>core</td></tr>
4487 <p>In many situations Apache httpd must construct a <em>self-referential</em>
4488 URL -- that is, a URL that refers back to the same server. With
4489 <code>UseCanonicalPhysicalPort On</code>, Apache httpd will, when
4490 constructing the canonical port for the server to honor
4491 the <code class="directive"><a href="#usecanonicalname">UseCanonicalName</a></code> directive,
4492 provide the actual physical port number being used by this request
4493 as a potential port. With <code>UseCanonicalPhysicalPort Off</code>,
4494 Apache httpd will not ever use the actual physical port number, instead
4495 relying on all configured information to construct a valid port number.</p>
4497 <div class="note"><h3>Note</h3>
4498 <p>The ordering of the lookup when the physical port is used is as
4501 <dt><code>UseCanonicalName On</code></dt>
4504 <li>Port provided in <code class="directive"><a href="#servername">Servername</a></code></li>
4505 <li>Physical port</li>
4506 <li>Default port</li>
4509 <dt><code>UseCanonicalName Off | DNS</code></dt>
4512 <li>Parsed port from <code>Host:</code> header</li>
4513 <li>Physical port</li>
4514 <li>Port provided in <code class="directive"><a href="#servername">Servername</a></code></li>
4515 <li>Default port</li>
4520 <p>With <code>UseCanonicalPhysicalPort Off</code>, the
4521 physical ports are removed from the ordering.</p>
4527 <li><code class="directive"><a href="#usecanonicalname">UseCanonicalName</a></code></li>
4528 <li><code class="directive"><a href="#servername">ServerName</a></code></li>
4529 <li><code class="directive"><a href="../mod/mpm_common.html#listen">Listen</a></code></li>
4532 <div class="top"><a href="#page-header"><img alt="top" src="../images/up.gif" /></a></div>
4533 <div class="directive-section"><h2><a name="VirtualHost" id="VirtualHost"><VirtualHost></a> <a name="virtualhost" id="virtualhost">Directive</a></h2>
4534 <table class="directive">
4535 <tr><th><a href="directive-dict.html#Description">Description:</a></th><td>Contains directives that apply only to a specific
4536 hostname or IP address</td></tr>
4537 <tr><th><a href="directive-dict.html#Syntax">Syntax:</a></th><td><code><VirtualHost
4538 <var>addr</var>[:<var>port</var>] [<var>addr</var>[:<var>port</var>]]
4539 ...> ... </VirtualHost></code></td></tr>
4540 <tr><th><a href="directive-dict.html#Context">Context:</a></th><td>server config</td></tr>
4541 <tr><th><a href="directive-dict.html#Status">Status:</a></th><td>Core</td></tr>
4542 <tr><th><a href="directive-dict.html#Module">Module:</a></th><td>core</td></tr>
4544 <p><code class="directive"><VirtualHost></code> and
4545 <code></VirtualHost></code> are used to enclose a group of
4546 directives that will apply only to a particular virtual host. Any
4547 directive that is allowed in a virtual host context may be
4548 used. When the server receives a request for a document on a
4549 particular virtual host, it uses the configuration directives
4550 enclosed in the <code class="directive"><VirtualHost></code>
4551 section. <var>Addr</var> can be any of the following, optionally followed by
4552 a colon and a port number (or *):</p>
4555 <li>The IP address of the virtual host;</li>
4557 <li>A fully qualified domain name for the IP address of the
4558 virtual host (not recommended);</li>
4560 <li>The character <code>*</code>, which acts as a wildcard and matches
4561 any IP address.</li>
4563 <li>The string <code>_default_</code>, which is an alias for <code>*</code></li>
4567 <pre class="prettyprint lang-config"><VirtualHost 10.1.2.3:80>
4568 ServerAdmin webmaster@host.example.com
4569 DocumentRoot "/www/docs/host.example.com"
4570 ServerName host.example.com
4571 ErrorLog "logs/host.example.com-error_log"
4572 TransferLog "logs/host.example.com-access_log"
4573 </VirtualHost></pre>
4577 <p>IPv6 addresses must be specified in square brackets because
4578 the optional port number could not be determined otherwise. An
4579 IPv6 example is shown below:</p>
4581 <pre class="prettyprint lang-config"><VirtualHost [2001:db8::a00:20ff:fea7:ccea]:80>
4582 ServerAdmin webmaster@host.example.com
4583 DocumentRoot "/www/docs/host.example.com"
4584 ServerName host.example.com
4585 ErrorLog "logs/host.example.com-error_log"
4586 TransferLog "logs/host.example.com-access_log"
4587 </VirtualHost></pre>
4590 <p>Each Virtual Host must correspond to a different IP address,
4591 different port number, or a different host name for the server,
4592 in the former case the server machine must be configured to
4593 accept IP packets for multiple addresses. (If the machine does
4594 not have multiple network interfaces, then this can be
4595 accomplished with the <code>ifconfig alias</code> command -- if
4596 your OS supports it).</p>
4598 <div class="note"><h3>Note</h3>
4599 <p>The use of <code class="directive"><VirtualHost></code> does
4600 <strong>not</strong> affect what addresses Apache httpd listens on. You
4601 may need to ensure that Apache httpd is listening on the correct addresses
4602 using <code class="directive"><a href="../mod/mpm_common.html#listen">Listen</a></code>.</p>
4605 <p>A <code class="directive"><a href="#servername">ServerName</a></code> should be
4606 specified inside each <code class="directive"><VirtualHost></code> block. If it is absent, the
4607 <code class="directive"><a href="#servername">ServerName</a></code> from the "main"
4608 server configuration will be inherited.</p>
4610 <p>When a request is received, the server first maps it to the best matching
4611 <code class="directive"><VirtualHost></code> based on the local
4612 IP address and port combination only. Non-wildcards have a higher
4613 precedence. If no match based on IP and port occurs at all, the
4614 "main" server configuration is used.</p>
4616 <p>If multiple virtual hosts contain the best matching IP address and port,
4617 the server selects from these virtual hosts the best match based on the
4618 requested hostname. If no matching name-based virtual host is found,
4619 then the first listed virtual host that matched the IP address will be
4620 used. As a consequence, the first listed virtual host for a given IP address
4621 and port combination is the default virtual host for that IP and port
4624 <div class="warning"><h3>Security</h3>
4625 <p>See the <a href="../misc/security_tips.html">security tips</a>
4626 document for details on why your security could be compromised if the
4627 directory where log files are stored is writable by anyone other
4628 than the user that starts the server.</p>
4633 <li><a href="../vhosts/">Apache HTTP Server Virtual Host documentation</a></li>
4634 <li><a href="../dns-caveats.html">Issues Regarding DNS and
4635 Apache HTTP Server</a></li>
4636 <li><a href="../bind.html">Setting
4637 which addresses and ports Apache HTTP Server uses</a></li>
4638 <li><a href="../sections.html">How <Directory>, <Location>
4639 and <Files> sections work</a> for an explanation of how these
4640 different sections are combined when a request is received</li>
4643 <div class="top"><a href="#page-header"><img alt="top" src="../images/up.gif" /></a></div>
4644 <div class="directive-section"><h2><a name="Warning" id="Warning">Warning</a> <a name="warning" id="warning">Directive</a></h2>
4645 <table class="directive">
4646 <tr><th><a href="directive-dict.html#Description">Description:</a></th><td>Warn from configuration parsing with a custom message</td></tr>
4647 <tr><th><a href="directive-dict.html#Syntax">Syntax:</a></th><td><code>Warning <var>message</var></code></td></tr>
4648 <tr><th><a href="directive-dict.html#Context">Context:</a></th><td>server config, virtual host, directory, .htaccess</td></tr>
4649 <tr><th><a href="directive-dict.html#Status">Status:</a></th><td>Core</td></tr>
4650 <tr><th><a href="directive-dict.html#Module">Module:</a></th><td>core</td></tr>
4651 <tr><th><a href="directive-dict.html#Compatibility">Compatibility:</a></th><td>2.5 and later</td></tr>
4653 <p>If an issue can be detected from within the configuration, this
4654 directive can be used to generate a custom warning message. The
4655 configuration parsing is not halted. The typical use is to check
4656 whether some user define options are set, and warn if not.</p>
4658 <pre class="prettyprint lang-config"># Example
4659 # tell when ReverseProxy is not set
4660 <IfDefine !ReverseProxy>
4661 Warning "reverse proxy is not started, hope this is okay!"
4664 <IfDefine ReverseProxy>
4665 # define custom proxy configuration
4666 </IfDefine></pre>
4672 <div class="bottomlang">
4673 <p><span>Available Languages: </span><a href="../de/mod/core.html" hreflang="de" rel="alternate" title="Deutsch"> de </a> |
4674 <a href="../en/mod/core.html" title="English"> en </a> |
4675 <a href="../es/mod/core.html" hreflang="es" rel="alternate" title="Español"> es </a> |
4676 <a href="../fr/mod/core.html" hreflang="fr" rel="alternate" title="Français"> fr </a> |
4677 <a href="../ja/mod/core.html" hreflang="ja" rel="alternate" title="Japanese"> ja </a> |
4678 <a href="../tr/mod/core.html" hreflang="tr" rel="alternate" title="Türkçe"> tr </a></p>
4679 </div><div class="top"><a href="#page-header"><img src="../images/up.gif" alt="top" /></a></div><div class="section"><h2><a id="comments_section" name="comments_section">Comments</a></h2><div class="warning"><strong>Notice:</strong><br />This is not a Q&A section. Comments placed here should be pointed towards suggestions on improving the documentation or server, and may be removed again by our moderators if they are either implemented or considered invalid/off-topic. Questions on how to manage the Apache HTTP Server should be directed at either our IRC channel, #httpd, on Freenode, or sent to our <a href="http://httpd.apache.org/lists.html">mailing lists</a>.</div>
4680 <script type="text/javascript"><!--//--><![CDATA[//><!--
4681 var comments_shortname = 'httpd';
4682 var comments_identifier = 'http://httpd.apache.org/docs/trunk/mod/core.html';
4684 if (w.location.hostname.toLowerCase() == "httpd.apache.org") {
4685 d.write('<div id="comments_thread"><\/div>');
4686 var s = d.createElement('script');
4687 s.type = 'text/javascript';
4689 s.src = 'https://comments.apache.org/show_comments.lua?site=' + comments_shortname + '&page=' + comments_identifier;
4690 (d.getElementsByTagName('head')[0] || d.getElementsByTagName('body')[0]).appendChild(s);
4693 d.write('<div id="comments_thread">Comments are disabled for this page at the moment.<\/div>');
4695 })(window, document);
4696 //--><!]]></script></div><div id="footer">
4697 <p class="apache">Copyright 2015 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>
4698 <p class="menu"><a href="../mod/">Modules</a> | <a href="../mod/quickreference.html">Directives</a> | <a href="http://wiki.apache.org/httpd/FAQ">FAQ</a> | <a href="../glossary.html">Glossary</a> | <a href="../sitemap.html">Sitemap</a></p></div><script type="text/javascript"><!--//--><
projects / apache / blob