core.xml revision 2f505ba07f89ba6a175d6ceae67fb273c4eb0993
530eba85dbd41b8a0fa5255d3648d1440199a661slive<!DOCTYPE modulesynopsis SYSTEM "/style/modulesynopsis.dtd">
e942c741056732f50da2074b36fe59805d370650slive<?xml-stylesheet type="text/xsl" href="/style/manual.en.xsl"?>
5f5d1b4cc970b7f06ff8ef6526128e9a27303d88nd<!-- $LastChangedRevision$ -->
db479b48bd4d75423ed4a45e15b75089d1a8ad72fielding Licensed to the Apache Software Foundation (ASF) under one or more
db479b48bd4d75423ed4a45e15b75089d1a8ad72fielding contributor license agreements. See the NOTICE file distributed with
db479b48bd4d75423ed4a45e15b75089d1a8ad72fielding this work for additional information regarding copyright ownership.
db479b48bd4d75423ed4a45e15b75089d1a8ad72fielding The ASF licenses this file to You under the Apache License, Version 2.0
db479b48bd4d75423ed4a45e15b75089d1a8ad72fielding (the "License"); you may not use this file except in compliance with
db479b48bd4d75423ed4a45e15b75089d1a8ad72fielding the License. You may obtain a copy of the License at
d5d794fc2f4cc9ca6d6da17cfa2cdcd8d244bacdnd Unless required by applicable law or agreed to in writing, software
d5d794fc2f4cc9ca6d6da17cfa2cdcd8d244bacdnd distributed under the License is distributed on an "AS IS" BASIS,
d5d794fc2f4cc9ca6d6da17cfa2cdcd8d244bacdnd WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
d5d794fc2f4cc9ca6d6da17cfa2cdcd8d244bacdnd See the License for the specific language governing permissions and
d5d794fc2f4cc9ca6d6da17cfa2cdcd8d244bacdnd limitations under the License.
80c4526970a11f37c0f8e3b82afdf03902dac3f3slive<description>Core Apache HTTP Server features that are always
80c4526970a11f37c0f8e3b82afdf03902dac3f3sliveavailable</description>
7e8f5c6496b3825b6b128e2aacc4b1b09d28553dpquerna<directivesynopsis>
7e8f5c6496b3825b6b128e2aacc4b1b09d28553dpquerna<description>Configures optimizations for a Protocol's Listener Sockets</description>
7e8f5c6496b3825b6b128e2aacc4b1b09d28553dpquerna<syntax>AcceptFilter <var>protocol</var> <var>accept_filter</var></syntax>
7e8f5c6496b3825b6b128e2aacc4b1b09d28553dpquerna<contextlist><context>server config</context></contextlist>
7e8f5c6496b3825b6b128e2aacc4b1b09d28553dpquerna<compatibility>Available in Apache httpd 2.1.5 and later.
7e8f5c6496b3825b6b128e2aacc4b1b09d28553dpquernaOn Windows from Apache httpd 2.3.3 and later.</compatibility>
7e8f5c6496b3825b6b128e2aacc4b1b09d28553dpquerna <p>This directive enables operating system specific optimizations for a
7e8f5c6496b3825b6b128e2aacc4b1b09d28553dpquerna listening socket by the Protocol type. The basic premise is for the
7e8f5c6496b3825b6b128e2aacc4b1b09d28553dpquerna kernel to not send a socket to the server process until either data
7e8f5c6496b3825b6b128e2aacc4b1b09d28553dpquerna is received or an entire HTTP Request is buffered. Only
7e8f5c6496b3825b6b128e2aacc4b1b09d28553dpquerna <a href="http://www.freebsd.org/cgi/man.cgi?query=accept_filter&sektion=9">
7e8f5c6496b3825b6b128e2aacc4b1b09d28553dpquerna FreeBSD's Accept Filters</a>, Linux's more primitive
7e8f5c6496b3825b6b128e2aacc4b1b09d28553dpquerna <code>TCP_DEFER_ACCEPT</code>, and Windows' optimized AcceptEx()
7e8f5c6496b3825b6b128e2aacc4b1b09d28553dpquerna are currently supported.</p>
7e8f5c6496b3825b6b128e2aacc4b1b09d28553dpquerna <p>Using <code>none</code> for an argument will disable any accept filters
7e8f5c6496b3825b6b128e2aacc4b1b09d28553dpquerna for that protocol. This is useful for protocols that require a server
7e8f5c6496b3825b6b128e2aacc4b1b09d28553dpquerna send data first, such as <code>ftp:</code> or <code>nntp</code>:</p>
7e8f5c6496b3825b6b128e2aacc4b1b09d28553dpquerna AcceptFilter http httpready <br/>
7e8f5c6496b3825b6b128e2aacc4b1b09d28553dpquerna AcceptFilter https dataready
7e8f5c6496b3825b6b128e2aacc4b1b09d28553dpquerna <p>The <code>httpready</code> accept filter buffers entire HTTP requests at
7e8f5c6496b3825b6b128e2aacc4b1b09d28553dpquerna the kernel level. Once an entire request is received, the kernel then
7e8f5c6496b3825b6b128e2aacc4b1b09d28553dpquerna sends it to the server. See the
7e8f5c6496b3825b6b128e2aacc4b1b09d28553dpquerna <a href="http://www.freebsd.org/cgi/man.cgi?query=accf_http&sektion=9">
7e8f5c6496b3825b6b128e2aacc4b1b09d28553dpquerna accf_http(9)</a> man page for more details. Since HTTPS requests are
7e8f5c6496b3825b6b128e2aacc4b1b09d28553dpquerna encrypted only the <a href="http://www.freebsd.org/cgi/man.cgi?query=accf_data&sektion=9">
7e8f5c6496b3825b6b128e2aacc4b1b09d28553dpquerna AcceptFilter http data <br/>
7e8f5c6496b3825b6b128e2aacc4b1b09d28553dpquerna AcceptFilter https data
7e8f5c6496b3825b6b128e2aacc4b1b09d28553dpquerna <p>Linux's <code>TCP_DEFER_ACCEPT</code> does not support buffering http
7e8f5c6496b3825b6b128e2aacc4b1b09d28553dpquerna requests. Any value besides <code>none</code> will enable
7e8f5c6496b3825b6b128e2aacc4b1b09d28553dpquerna <code>TCP_DEFER_ACCEPT</code> on that listener. For more details
3139522a1418fa699dfd78dcf8dde54253f2c55cnoirin see the Linux
7e8f5c6496b3825b6b128e2aacc4b1b09d28553dpquerna <a href="http://homepages.cwi.nl/~aeb/linux/man2html/man7/tcp.7.html">
80c4526970a11f37c0f8e3b82afdf03902dac3f3slive AcceptFilter http data <br/>
313bb560bc5c323cfd40c9cad7335b4b8e060aedkess AcceptFilter https data
80c4526970a11f37c0f8e3b82afdf03902dac3f3slive <p>Window's mpm_winnt interprets the AcceptFilter to toggle the AcceptEx()
80c4526970a11f37c0f8e3b82afdf03902dac3f3slive API, and does not support http protocol buffering. There are two values
80c4526970a11f37c0f8e3b82afdf03902dac3f3slive which utilize the Windows AcceptEx() API and will recycle network
18b4b0fd6056093002ddef488636bf5ebe415ef0erikabele sockets between connections. <code>data</code> waits until data has
80c4526970a11f37c0f8e3b82afdf03902dac3f3slive been transmitted as documented above, and the initial data buffer and
80c4526970a11f37c0f8e3b82afdf03902dac3f3slive network endpoint addresses are all retrieved from the single AcceptEx()
80c4526970a11f37c0f8e3b82afdf03902dac3f3slive invocation. <code>connect</code> will use the AcceptEx() API, also
80c4526970a11f37c0f8e3b82afdf03902dac3f3slive retrieve the network endpoint addresses, but like <code>none</code>
80c4526970a11f37c0f8e3b82afdf03902dac3f3slive the <code>connect</code> option does not wait for the initial data
80c4526970a11f37c0f8e3b82afdf03902dac3f3slive transmission.</p>
80c4526970a11f37c0f8e3b82afdf03902dac3f3slive <p>On Windows, <code>none</code> uses accept() rather than than AcceptEx()
fb77c505254b6e9c925e23e734463e87574f8f40kess and will not recycle sockets between connections. This is useful for
fb77c505254b6e9c925e23e734463e87574f8f40kess network adapters with broken driver support, as well as some virtual
80c4526970a11f37c0f8e3b82afdf03902dac3f3slive network providers such as vpn drivers, or spam, virus or spyware
80c4526970a11f37c0f8e3b82afdf03902dac3f3slive filters.</p>
80c4526970a11f37c0f8e3b82afdf03902dac3f3slive</directivesynopsis>
fb77c505254b6e9c925e23e734463e87574f8f40kess<directivesynopsis>
80c4526970a11f37c0f8e3b82afdf03902dac3f3slive<description>Resources accept trailing pathname information</description>
80c4526970a11f37c0f8e3b82afdf03902dac3f3slive<context>virtual host</context><context>directory</context>
80c4526970a11f37c0f8e3b82afdf03902dac3f3slive<compatibility>Available in Apache httpd 2.0.30 and later</compatibility>
80c4526970a11f37c0f8e3b82afdf03902dac3f3slive <p>This directive controls whether requests that contain trailing
80c4526970a11f37c0f8e3b82afdf03902dac3f3slive pathname information that follows an actual filename (or
fb77c505254b6e9c925e23e734463e87574f8f40kess non-existent file in an existing directory) will be accepted or
fb77c505254b6e9c925e23e734463e87574f8f40kess rejected. The trailing pathname information can be made
80c4526970a11f37c0f8e3b82afdf03902dac3f3slive available to scripts in the <code>PATH_INFO</code> environment
80c4526970a11f37c0f8e3b82afdf03902dac3f3slive variable.</p>
6b64034fa2a644ba291c484c0c01c7df5b8d982ckess <p>For example, assume the location <code>/test/</code> points to
80c4526970a11f37c0f8e3b82afdf03902dac3f3slive a directory that contains only the single file
80c4526970a11f37c0f8e3b82afdf03902dac3f3slive <p>The three possible arguments for the
fb77c505254b6e9c925e23e734463e87574f8f40kess <directive>AcceptPathInfo</directive> directive are:</p>
80c4526970a11f37c0f8e3b82afdf03902dac3f3slive <dt><code>Off</code></dt><dd>A request will only be accepted if it
fb77c505254b6e9c925e23e734463e87574f8f40kess maps to a literal path that exists. Therefore a request with
fb77c505254b6e9c925e23e734463e87574f8f40kess trailing pathname information after the true filename such as
80c4526970a11f37c0f8e3b82afdf03902dac3f3slive <code>/test/here.html/more</code> in the above example will return
a7f40ca49262952d6dd69d021cf5b0c2b452ae4cnd a 404 NOT FOUND error.</dd>
130d299c4b2b15be45532a176604c71fdc7bea5bnd <dt><code>On</code></dt><dd>A request will be accepted if a
130d299c4b2b15be45532a176604c71fdc7bea5bnd leading path component maps to a file that exists. The above
130d299c4b2b15be45532a176604c71fdc7bea5bnd example <code>/test/here.html/more</code> will be accepted if
130d299c4b2b15be45532a176604c71fdc7bea5bnd <dt><code>Default</code></dt><dd>The treatment of requests with
130d299c4b2b15be45532a176604c71fdc7bea5bnd trailing pathname information is determined by the <a
a7f40ca49262952d6dd69d021cf5b0c2b452ae4cnd href="/handler.html">handler</a> responsible for the request.
a7f40ca49262952d6dd69d021cf5b0c2b452ae4cnd The core handler for normal files defaults to rejecting
80c4526970a11f37c0f8e3b82afdf03902dac3f3slive <code>PATH_INFO</code> requests. Handlers that serve scripts, such as <a
80c4526970a11f37c0f8e3b82afdf03902dac3f3slive href="mod_isapi.html">isapi-handler</a>, generally accept
a7f40ca49262952d6dd69d021cf5b0c2b452ae4cnd <p>The primary purpose of the <code>AcceptPathInfo</code>
80c4526970a11f37c0f8e3b82afdf03902dac3f3slive directive is to allow you to override the handler's choice of
80c4526970a11f37c0f8e3b82afdf03902dac3f3slive accepting or rejecting <code>PATH_INFO</code>. This override is required,
80c4526970a11f37c0f8e3b82afdf03902dac3f3slive for example, when you use a <a href="/filter.html">filter</a>, such
80c4526970a11f37c0f8e3b82afdf03902dac3f3slive as <a href="mod_include.html">INCLUDES</a>, to generate content
80c4526970a11f37c0f8e3b82afdf03902dac3f3slive based on <code>PATH_INFO</code>. The core handler would usually reject
313bb560bc5c323cfd40c9cad7335b4b8e060aedkess the request, so you can use the following configuration to enable
003f0c9fda6664daf5092a0e42f65ede20098153slive such a script:</p>
a7f40ca49262952d6dd69d021cf5b0c2b452ae4cnd Options +Includes<br />
a7f40ca49262952d6dd69d021cf5b0c2b452ae4cnd SetOutputFilter INCLUDES<br />
a7f40ca49262952d6dd69d021cf5b0c2b452ae4cnd AcceptPathInfo On<br />
80c4526970a11f37c0f8e3b82afdf03902dac3f3slive </Files>
80c4526970a11f37c0f8e3b82afdf03902dac3f3slive</directivesynopsis>
130d299c4b2b15be45532a176604c71fdc7bea5bnd<directivesynopsis>
130d299c4b2b15be45532a176604c71fdc7bea5bnd<description>Name of the distributed configuration file</description>
130d299c4b2b15be45532a176604c71fdc7bea5bnd<syntax>AccessFileName <var>filename</var> [<var>filename</var>] ...</syntax>
130d299c4b2b15be45532a176604c71fdc7bea5bnd<contextlist><context>server config</context><context>virtual host</context>
a7f40ca49262952d6dd69d021cf5b0c2b452ae4cnd</contextlist>
80c4526970a11f37c0f8e3b82afdf03902dac3f3slive <p>While processing a request the server looks for
1a3f62ca37273a15a06bb94a61d3c6fcf4bf38c9rbowen the first existing configuration file from this list of names in
80c4526970a11f37c0f8e3b82afdf03902dac3f3slive every directory of the path to the document, if distributed
80c4526970a11f37c0f8e3b82afdf03902dac3f3slive configuration files are <a href="#allowoverride">enabled for that
684f2a9a422185adda0692a1203c5ad6687fc5c5nd AccessFileName .acl
a7f40ca49262952d6dd69d021cf5b0c2b452ae4cnd </example>
80c4526970a11f37c0f8e3b82afdf03902dac3f3slive <p>before returning the document
80c4526970a11f37c0f8e3b82afdf03902dac3f3slive <code>/usr/local/web/index.html</code>, the server will read
003f0c9fda6664daf5092a0e42f65ede20098153slive <code>/usr/local/.acl</code> and <code>/usr/local/web/.acl</code>
80c4526970a11f37c0f8e3b82afdf03902dac3f3slive for directives, unless they have been disabled with</p>
843a03fe0b138a4c1f64cb90a014e9417ac30691fielding <Directory /><br />
684f2a9a422185adda0692a1203c5ad6687fc5c5nd AllowOverride None<br />
684f2a9a422185adda0692a1203c5ad6687fc5c5nd </Directory>
843a03fe0b138a4c1f64cb90a014e9417ac30691fielding<seealso><directive module="core">AllowOverride</directive></seealso>
843a03fe0b138a4c1f64cb90a014e9417ac30691fielding<seealso><a href="/configuring.html">Configuration Files</a></seealso>
843a03fe0b138a4c1f64cb90a014e9417ac30691fielding<seealso><a href="/howto/htaccess.html">.htaccess Files</a></seealso>
843a03fe0b138a4c1f64cb90a014e9417ac30691fielding</directivesynopsis>
80c4526970a11f37c0f8e3b82afdf03902dac3f3slive<directivesynopsis>
a7f40ca49262952d6dd69d021cf5b0c2b452ae4cnd<description>Default charset parameter to be added when a response
a7f40ca49262952d6dd69d021cf5b0c2b452ae4cndcontent-type is <code>text/plain</code> or <code>text/html</code></description>
843a03fe0b138a4c1f64cb90a014e9417ac30691fielding<syntax>AddDefaultCharset On|Off|<var>charset</var></syntax>
843a03fe0b138a4c1f64cb90a014e9417ac30691fielding<context>virtual host</context><context>directory</context>
843a03fe0b138a4c1f64cb90a014e9417ac30691fielding <p>This directive specifies a default value for the media type
843a03fe0b138a4c1f64cb90a014e9417ac30691fielding charset parameter (the name of a character encoding) to be added
843a03fe0b138a4c1f64cb90a014e9417ac30691fielding to a response if and only if the response's content-type is either
80c4526970a11f37c0f8e3b82afdf03902dac3f3slive <code>text/plain</code> or <code>text/html</code>. This should override
843a03fe0b138a4c1f64cb90a014e9417ac30691fielding any charset specified in the body of the response via a <code>META</code>
80c4526970a11f37c0f8e3b82afdf03902dac3f3slive element, though the exact behavior is often dependent on the user's client
80c4526970a11f37c0f8e3b82afdf03902dac3f3slive configuration. A setting of <code>AddDefaultCharset Off</code>
58699879a562774640b95e9eedfd891f336e38c2nd disables this functionality. <code>AddDefaultCharset On</code> enables
58699879a562774640b95e9eedfd891f336e38c2nd a default charset of <code>iso-8859-1</code>. Any other value is assumed
58699879a562774640b95e9eedfd891f336e38c2nd to be the <var>charset</var> to be used, which should be one of the
fb77c505254b6e9c925e23e734463e87574f8f40kess <a href="http://www.iana.org/assignments/character-sets">IANA registered
fb77c505254b6e9c925e23e734463e87574f8f40kess charset values</a> for use in Internet media types (MIME types).
58699879a562774640b95e9eedfd891f336e38c2nd For example:</p>
58699879a562774640b95e9eedfd891f336e38c2nd AddDefaultCharset utf-8
58699879a562774640b95e9eedfd891f336e38c2nd <p><directive>AddDefaultCharset</directive> should only be used when all
58699879a562774640b95e9eedfd891f336e38c2nd of the text resources to which it applies are known to be in that
58699879a562774640b95e9eedfd891f336e38c2nd character encoding and it is too inconvenient to label their charset
a2920e90d95fa04c15bdbbc03e7f8636eac92423slive individually. One such example is to add the charset parameter
a2920e90d95fa04c15bdbbc03e7f8636eac92423slive to resources containing generated content, such as legacy CGI
a2920e90d95fa04c15bdbbc03e7f8636eac92423slive scripts, that might be vulnerable to cross-site scripting attacks
58699879a562774640b95e9eedfd891f336e38c2nd due to user-provided data being included in the output. Note, however,
fb77c505254b6e9c925e23e734463e87574f8f40kess that a better solution is to just fix (or delete) those scripts, since
fb77c505254b6e9c925e23e734463e87574f8f40kess setting a default charset does not protect users that have enabled
fb77c505254b6e9c925e23e734463e87574f8f40kess the "auto-detect character encoding" feature on their browser.</p>
fb77c505254b6e9c925e23e734463e87574f8f40kess<seealso><directive module="mod_mime">AddCharset</directive></seealso>
58699879a562774640b95e9eedfd891f336e38c2nd</directivesynopsis>
58699879a562774640b95e9eedfd891f336e38c2nd<directivesynopsis>
58699879a562774640b95e9eedfd891f336e38c2nd<description>Determines whether encoded path separators in URLs are allowed to
6b64034fa2a644ba291c484c0c01c7df5b8d982ckessbe passed through</description>
6b64034fa2a644ba291c484c0c01c7df5b8d982ckess<contextlist><context>server config</context><context>virtual host</context>
58699879a562774640b95e9eedfd891f336e38c2nd</contextlist>
58699879a562774640b95e9eedfd891f336e38c2nd<compatibility>Available in Apache httpd 2.0.46 and later</compatibility>
fb77c505254b6e9c925e23e734463e87574f8f40kess <p>The <directive>AllowEncodedSlashes</directive> directive allows URLs
58699879a562774640b95e9eedfd891f336e38c2nd which contain encoded path separators (<code>%2F</code> for <code>/</code>
58699879a562774640b95e9eedfd891f336e38c2nd and additionally <code>%5C</code> for <code>\</code> on according systems)
58699879a562774640b95e9eedfd891f336e38c2nd to be used. Normally such URLs are refused with a 404 (Not found) error.</p>
58699879a562774640b95e9eedfd891f336e38c2nd <p>Turning <directive>AllowEncodedSlashes</directive> <code>On</code> is
58699879a562774640b95e9eedfd891f336e38c2nd mostly useful when used in conjunction with <code>PATH_INFO</code>.</p>
58699879a562774640b95e9eedfd891f336e38c2nd <p>Allowing encoded slashes does <em>not</em> imply <em>decoding</em>.
58699879a562774640b95e9eedfd891f336e38c2nd Occurrences of <code>%2F</code> or <code>%5C</code> (<em>only</em> on
313bb560bc5c323cfd40c9cad7335b4b8e060aedkess according systems) will be left as such in the otherwise decoded URL
4a7affccb2f1f5b94cab395e1bf3825aed715ebcnd string.</p>
6b64034fa2a644ba291c484c0c01c7df5b8d982ckess<seealso><directive module="core">AcceptPathInfo</directive></seealso>
6b64034fa2a644ba291c484c0c01c7df5b8d982ckess</directivesynopsis>
4a7affccb2f1f5b94cab395e1bf3825aed715ebcnd<directivesynopsis>
9b5e2c5e769dc678a1aca06df75c32022b2f1492trawick<description>Types of directives that are allowed in
58699879a562774640b95e9eedfd891f336e38c2nd <p>When the server finds an <code>.htaccess</code> file (as
58699879a562774640b95e9eedfd891f336e38c2nd specified by <directive module="core">AccessFileName</directive>)
4a7affccb2f1f5b94cab395e1bf3825aed715ebcnd it needs to know which directives declared in that file can override
58699879a562774640b95e9eedfd891f336e38c2nd earlier configuration directives.</p>
77ead9e0262e4f08ec336d1a65b2edef7705c839nd <note><title>Only available in <Directory> sections</title>
9583adab6bc4b3758e41963c905d9dad9f067131nd <directive type="section" module="core">Directory</directive>
77ead9e0262e4f08ec336d1a65b2edef7705c839nd sections specified without regular expressions, not in <directive
77ead9e0262e4f08ec336d1a65b2edef7705c839nd type="section" module="core">Location</directive>, <directive
77ead9e0262e4f08ec336d1a65b2edef7705c839nd module="core" type="section">DirectoryMatch</directive> or
77ead9e0262e4f08ec336d1a65b2edef7705c839nd <directive type="section" module="core">Files</directive> sections.
77ead9e0262e4f08ec336d1a65b2edef7705c839nd <a href="#accessfilename">.htaccess</a> files are completely ignored.
77ead9e0262e4f08ec336d1a65b2edef7705c839nd In this case, the server will not even attempt to read
77ead9e0262e4f08ec336d1a65b2edef7705c839nd <p>When this directive is set to <code>All</code>, then any
77ead9e0262e4f08ec336d1a65b2edef7705c839nd directive which has the .htaccess <a
77ead9e0262e4f08ec336d1a65b2edef7705c839nd href="directive-dict.html#Context">Context</a> is allowed in
77ead9e0262e4f08ec336d1a65b2edef7705c839nd <p>The <var>directive-type</var> can be one of the following
77ead9e0262e4f08ec336d1a65b2edef7705c839nd groupings of directives.</p>
77ead9e0262e4f08ec336d1a65b2edef7705c839nd Allow use of the authorization directives (<directive
80c4526970a11f37c0f8e3b82afdf03902dac3f3slive <directive module="mod_authn_dbm">AuthDBMUserFile</directive>,
80c4526970a11f37c0f8e3b82afdf03902dac3f3slive <directive module="mod_authz_groupfile">AuthGroupFile</directive>,
003f0c9fda6664daf5092a0e42f65ede20098153slive <directive module="mod_authn_core">AuthName</directive>,
313bb560bc5c323cfd40c9cad7335b4b8e060aedkess <directive module="mod_authn_core">AuthType</directive>, <directive
fb77c505254b6e9c925e23e734463e87574f8f40kess module="mod_authn_file">AuthUserFile</directive>, <directive
a7f40ca49262952d6dd69d021cf5b0c2b452ae4cnd module="mod_authz_core">Require</directive>, <em>etc.</em>).</dd>
fb77c505254b6e9c925e23e734463e87574f8f40kess Allow use of the directives controlling document types
6b64034fa2a644ba291c484c0c01c7df5b8d982ckess <directive module="mod_negotiation">LanguagePriority</directive>,
10673857794a4b3d9568ca2d983722a87ed352f1rbowen <directive module="core">SetOutputFilter</directive>, and
fb77c505254b6e9c925e23e734463e87574f8f40kess <module>mod_mime</module> Add* and Remove* directives),
b12b918ae6baf9c5762ed61b7393d0e2198378c0nd document meta data (<directive
b12b918ae6baf9c5762ed61b7393d0e2198378c0nd module="mod_headers">RequestHeader</directive>, <directive
10673857794a4b3d9568ca2d983722a87ed352f1rbowen module="mod_setenvif">SetEnvIfNoCase</directive>, <directive
10673857794a4b3d9568ca2d983722a87ed352f1rbowen module="mod_setenvif">BrowserMatch</directive>, <directive
80c4526970a11f37c0f8e3b82afdf03902dac3f3slive module="mod_usertrack">CookieExpires</directive>, <directive
fb77c505254b6e9c925e23e734463e87574f8f40kess module="mod_usertrack">CookieDomain</directive>, <directive
fb77c505254b6e9c925e23e734463e87574f8f40kess module="mod_usertrack">CookieStyle</directive>, <directive
fb77c505254b6e9c925e23e734463e87574f8f40kess module="mod_usertrack">CookieTracking</directive>, <directive
80c4526970a11f37c0f8e3b82afdf03902dac3f3slive module="mod_rewrite">RewriteEngine</directive>, <directive
80c4526970a11f37c0f8e3b82afdf03902dac3f3slive module="mod_rewrite">RewriteOptions</directive>, <directive
fb77c505254b6e9c925e23e734463e87574f8f40kess module="mod_rewrite">RewriteBase</directive>, <directive
80c4526970a11f37c0f8e3b82afdf03902dac3f3slive module="mod_rewrite">RewriteCond</directive>, <directive
80c4526970a11f37c0f8e3b82afdf03902dac3f3slive <directive module="mod_actions">Action</directive> from
80c4526970a11f37c0f8e3b82afdf03902dac3f3slive Allow use of the directives controlling directory indexing
1f53e295ebd19aed1767d12da7abfab9936c148cjerenkrantz module="mod_autoindex">AddDescription</directive>,
9ed9eaf871c58d281af02e76125ceadb5060afa5nd <directive module="mod_autoindex">AddIcon</directive>, <directive
9cd3b05d7b70f07a742bbaf548fa4fa2bdbe5ce6noodl <directive module="mod_autoindex">AddIconByType</directive>,
1f53e295ebd19aed1767d12da7abfab9936c148cjerenkrantz <directive module="mod_autoindex">DefaultIcon</directive>, <directive
9cd3b05d7b70f07a742bbaf548fa4fa2bdbe5ce6noodl module="mod_dir">DirectoryIndex</directive>, <directive
80c4526970a11f37c0f8e3b82afdf03902dac3f3slive module="mod_autoindex">FancyIndexing</directive>, <directive
80c4526970a11f37c0f8e3b82afdf03902dac3f3slive module="mod_autoindex">HeaderName</directive>, <directive
80c4526970a11f37c0f8e3b82afdf03902dac3f3slive module="mod_autoindex">IndexIgnore</directive>, <directive
80c4526970a11f37c0f8e3b82afdf03902dac3f3slive module="mod_autoindex">IndexOptions</directive>, <directive
80c4526970a11f37c0f8e3b82afdf03902dac3f3slive Allow use of the directives controlling host access (<directive
80c4526970a11f37c0f8e3b82afdf03902dac3f3slive module="mod_authz_host">Deny</directive> and <directive
5528d1a30ae8560e2d7a96d734ffe31500dc6113rpluem Allow use of the directives controlling specific directory
5528d1a30ae8560e2d7a96d734ffe31500dc6113rpluem features (<directive module="core">Options</directive> and
5528d1a30ae8560e2d7a96d734ffe31500dc6113rpluem <directive module="mod_include">XBitHack</directive>).
5528d1a30ae8560e2d7a96d734ffe31500dc6113rpluem An equal sign may be given followed by a comma (but no spaces)
5528d1a30ae8560e2d7a96d734ffe31500dc6113rpluem separated lists of options that may be set using the <directive
5528d1a30ae8560e2d7a96d734ffe31500dc6113rpluem AllowOverride AuthConfig Indexes
5528d1a30ae8560e2d7a96d734ffe31500dc6113rpluem <p>In the example above all directives that are neither in the group
80c4526970a11f37c0f8e3b82afdf03902dac3f3slive <code>AuthConfig</code> nor <code>Indexes</code> cause an internal
80c4526970a11f37c0f8e3b82afdf03902dac3f3slive server error.</p>
80c4526970a11f37c0f8e3b82afdf03902dac3f3slive <note><p>For security and performance reasons, do not set
80c4526970a11f37c0f8e3b82afdf03902dac3f3slive <code>AllowOverride</code> to anything other than <code>None</code>
80c4526970a11f37c0f8e3b82afdf03902dac3f3slive in your <code><Directory /></code> block. Instead, find (or
80c4526970a11f37c0f8e3b82afdf03902dac3f3slive create) the <code><Directory></code> block that refers to the
80c4526970a11f37c0f8e3b82afdf03902dac3f3slive directory where you're actually planning to place a
80c4526970a11f37c0f8e3b82afdf03902dac3f3slive<seealso><directive module="core">AccessFileName</directive></seealso>
80c4526970a11f37c0f8e3b82afdf03902dac3f3slive<seealso><a href="/configuring.html">Configuration Files</a></seealso>
80c4526970a11f37c0f8e3b82afdf03902dac3f3slive<seealso><a href="/howto/htaccess.html">.htaccess Files</a></seealso>
80c4526970a11f37c0f8e3b82afdf03902dac3f3slive</directivesynopsis>
80c4526970a11f37c0f8e3b82afdf03902dac3f3slive<directivesynopsis>
80c4526970a11f37c0f8e3b82afdf03902dac3f3slive<description>Technique for locating the interpreter for CGI
80c4526970a11f37c0f8e3b82afdf03902dac3f3slivescripts</description>
80c4526970a11f37c0f8e3b82afdf03902dac3f3slive<syntax>CGIMapExtension <var>cgi-path</var> <var>.extension</var></syntax>
80c4526970a11f37c0f8e3b82afdf03902dac3f3slive<contextlist><context>directory</context><context>.htaccess</context>
9ed9eaf871c58d281af02e76125ceadb5060afa5nd</contextlist>
80c4526970a11f37c0f8e3b82afdf03902dac3f3slive <p>This directive is used to control how Apache httpd finds the
80c4526970a11f37c0f8e3b82afdf03902dac3f3slive interpreter used to run CGI scripts. For example, setting
80c4526970a11f37c0f8e3b82afdf03902dac3f3slive cause all CGI script files with a <code>.foo</code> extension to
103a93c625bcde1a6a7a5155b64dcda36f612180pquerna be passed to the FOO interpreter.</p>
f23fb63b05f89f47d7a3099491f2c68dcce432e9kess</directivesynopsis>
80c4526970a11f37c0f8e3b82afdf03902dac3f3slive<directivesynopsis>
80c4526970a11f37c0f8e3b82afdf03902dac3f3slive<description>Enables the generation of <code>Content-MD5</code> HTTP Response
80c4526970a11f37c0f8e3b82afdf03902dac3f3sliveheaders</description>
a7f40ca49262952d6dd69d021cf5b0c2b452ae4cnd<contextlist><context>server config</context><context>virtual host</context>
b12b918ae6baf9c5762ed61b7393d0e2198378c0nd</contextlist>
da637bcae7b6e150470e701af29da5604a34a17erbowen <p>This directive enables the generation of
da637bcae7b6e150470e701af29da5604a34a17erbowen <code>Content-MD5</code> headers as defined in RFC1864
da637bcae7b6e150470e701af29da5604a34a17erbowen respectively RFC2616.</p>
da637bcae7b6e150470e701af29da5604a34a17erbowen <p>MD5 is an algorithm for computing a "message digest"
da637bcae7b6e150470e701af29da5604a34a17erbowen (sometimes called "fingerprint") of arbitrary-length data, with
80c4526970a11f37c0f8e3b82afdf03902dac3f3slive a high degree of confidence that any alterations in the data
80c4526970a11f37c0f8e3b82afdf03902dac3f3slive will be reflected in alterations in the message digest.</p>
80c4526970a11f37c0f8e3b82afdf03902dac3f3slive <p>The <code>Content-MD5</code> header provides an end-to-end
54bcd0e21a5c79158afd3b78bf707a493a5fb33crbowen message integrity check (MIC) of the entity-body. A proxy or
80c4526970a11f37c0f8e3b82afdf03902dac3f3slive client may check this header for detecting accidental
80c4526970a11f37c0f8e3b82afdf03902dac3f3slive modification of the entity-body in transit. Example header:</p>
fb77c505254b6e9c925e23e734463e87574f8f40kess Content-MD5: AuLb7Dp1rqtRtxz2m9kRpA==
4c7bdb15764021d39e486adb7bc2166d3f683773bnicholes <p>Note that this can cause performance problems on your server
4c7bdb15764021d39e486adb7bc2166d3f683773bnicholes since the message digest is computed on every request (the
4c7bdb15764021d39e486adb7bc2166d3f683773bnicholes values are not cached).</p>
4c7bdb15764021d39e486adb7bc2166d3f683773bnicholes <p><code>Content-MD5</code> is only sent for documents served
4c7bdb15764021d39e486adb7bc2166d3f683773bnicholes by the <module>core</module>, and not by any module. For example,
4c7bdb15764021d39e486adb7bc2166d3f683773bnicholes SSI documents, output from CGI scripts, and byte range responses
fb77c505254b6e9c925e23e734463e87574f8f40kess do not have this header.</p>
313bb560bc5c323cfd40c9cad7335b4b8e060aedkess</directivesynopsis>
4c7bdb15764021d39e486adb7bc2166d3f683773bnicholes<directivesynopsis>
4c7bdb15764021d39e486adb7bc2166d3f683773bnicholes<description>This directive has no effect other than to emit warnings
80c4526970a11f37c0f8e3b82afdf03902dac3f3sliveif the value is not <code>none</code>. In prior versions, DefaultType
80c4526970a11f37c0f8e3b82afdf03902dac3f3slivewould specify a default media type to assign to response content for
313bb560bc5c323cfd40c9cad7335b4b8e060aedkesswhich no other media type configuration could be found.
fb77c505254b6e9c925e23e734463e87574f8f40kess</description>
80c4526970a11f37c0f8e3b82afdf03902dac3f3slive<contextlist><context>server config</context><context>virtual host</context>
80c4526970a11f37c0f8e3b82afdf03902dac3f3slive<context>directory</context><context>.htaccess</context>
80c4526970a11f37c0f8e3b82afdf03902dac3f3slive</contextlist>
80c4526970a11f37c0f8e3b82afdf03902dac3f3slive<compatibility>The argument <code>none</code> is available in Apache httpd 2.2.7 and later. All other choices are DISABLED for 2.3.x and later.</compatibility>
80c4526970a11f37c0f8e3b82afdf03902dac3f3slive <p>This directive has been disabled. For backwards compatibility
80c4526970a11f37c0f8e3b82afdf03902dac3f3slive of configuration files, it may be specified with the value
5bb5fba250bf526bc51d13b25378d54acb93c1cbnoodl <code>none</code>, meaning no default media type. For example:</p>
80c4526970a11f37c0f8e3b82afdf03902dac3f3slive DefaultType None
80c4526970a11f37c0f8e3b82afdf03902dac3f3slive httpd-2.2.7 and later.</p>
80c4526970a11f37c0f8e3b82afdf03902dac3f3slive <directive module="mod_mime">AddType</directive> to configure media
a7f40ca49262952d6dd69d021cf5b0c2b452ae4cnd type assignments via file extensions, or the
a7f40ca49262952d6dd69d021cf5b0c2b452ae4cnd <directive module="core">ForceType</directive> directive to configure
a7f40ca49262952d6dd69d021cf5b0c2b452ae4cnd the media type for specific resources. Otherwise, the server will
a7f40ca49262952d6dd69d021cf5b0c2b452ae4cnd send the response without a Content-Type header field and the
80c4526970a11f37c0f8e3b82afdf03902dac3f3slive recipient may attempt to guess the media type.</p>
80c4526970a11f37c0f8e3b82afdf03902dac3f3slive</directivesynopsis>
80c4526970a11f37c0f8e3b82afdf03902dac3f3slive<directivesynopsis>
fb77c505254b6e9c925e23e734463e87574f8f40kess<description>Define the existence of a variable</description>
fb77c505254b6e9c925e23e734463e87574f8f40kess<contextlist><context>server config</context></contextlist>
80c4526970a11f37c0f8e3b82afdf03902dac3f3slive <p>Equivalent to passing the <code>-D</code> argument to <program
80c4526970a11f37c0f8e3b82afdf03902dac3f3slive <p>This directive can be used to toggle the use of <directive module="core"
003f0c9fda6664daf5092a0e42f65ede20098153slive type="section">IfDefine</directive> sections without needing to alter
76f2a3125fb6aca59d43b02220dabac91175a281slive</directivesynopsis>
80c4526970a11f37c0f8e3b82afdf03902dac3f3slive<description>Enclose a group of directives that apply only to the
ccf2a600dd72cc3c3c44f5d4126d9bb60fa83894takashinamed file-system directory and sub-directories</description>
80c4526970a11f37c0f8e3b82afdf03902dac3f3slive... </Directory></syntax>
80c4526970a11f37c0f8e3b82afdf03902dac3f3slive<contextlist><context>server config</context><context>virtual host</context>
c14037646789087319802aaada2e8534ccab0158slive</contextlist>
dcfabbc1bf4b0aa835e0c5ba7da3e8d12d8299c7niq <code></Directory></code> are used to enclose a group of
dcfabbc1bf4b0aa835e0c5ba7da3e8d12d8299c7niq directives that will apply only to the named directory and
80c4526970a11f37c0f8e3b82afdf03902dac3f3slive sub-directories of that directory. Any directive that is allowed
80c4526970a11f37c0f8e3b82afdf03902dac3f3slive in a directory context may be used. <var>Directory-path</var> is
a7f40ca49262952d6dd69d021cf5b0c2b452ae4cnd either the full path to a directory, or a wild-card string using
a7f40ca49262952d6dd69d021cf5b0c2b452ae4cnd Unix shell-style matching. In a wild-card string, <code>?</code> matches
a7f40ca49262952d6dd69d021cf5b0c2b452ae4cnd any single character, and <code>*</code> matches any sequences of
a7f40ca49262952d6dd69d021cf5b0c2b452ae4cnd characters. You may also use <code>[]</code> character ranges. None
6b64034fa2a644ba291c484c0c01c7df5b8d982ckess of the wildcards match a `/' character, so <code><Directory
fb77c505254b6e9c925e23e734463e87574f8f40kess /*/public_html></code> will not match
80c4526970a11f37c0f8e3b82afdf03902dac3f3slive <code>/home/user/public_html</code>, but <code><Directory
e4881891552e185a7408318dfc7f62ebabe73cf6niq Options Indexes FollowSymLinks<br />
ccf2a600dd72cc3c3c44f5d4126d9bb60fa83894takashi </Directory>
e4881891552e185a7408318dfc7f62ebabe73cf6niq </example>
80c4526970a11f37c0f8e3b82afdf03902dac3f3slive <p>Be careful with the <var>directory-path</var> arguments:
80c4526970a11f37c0f8e3b82afdf03902dac3f3slive They have to literally match the filesystem path which Apache httpd uses
313bb560bc5c323cfd40c9cad7335b4b8e060aedkess to access the files. Directives applied to a particular
80c4526970a11f37c0f8e3b82afdf03902dac3f3slive <code><Directory></code> will not apply to files accessed from
80c4526970a11f37c0f8e3b82afdf03902dac3f3slive that same directory via a different path, such as via different symbolic
6e483e0b8aa3fa574288a7452221392a03e2b9a3noodl expressions</glossary> can also be used, with the addition of the
ccf2a600dd72cc3c3c44f5d4126d9bb60fa83894takashi <Directory ~ "^/www/.*/[0-9]{3}">
6e483e0b8aa3fa574288a7452221392a03e2b9a3noodl <p>would match directories in <code>/www/</code> that consisted of
6e483e0b8aa3fa574288a7452221392a03e2b9a3noodl three numbers.</p>
80c4526970a11f37c0f8e3b82afdf03902dac3f3slive match the directory (or one of its parents) containing a document,
80c4526970a11f37c0f8e3b82afdf03902dac3f3slive then the directives are applied in the order of shortest match
80c4526970a11f37c0f8e3b82afdf03902dac3f3slive first, interspersed with the directives from the <a
80c4526970a11f37c0f8e3b82afdf03902dac3f3slive href="#accessfilename">.htaccess</a> files. For example,
80c4526970a11f37c0f8e3b82afdf03902dac3f3slive <Directory /><br />
80c4526970a11f37c0f8e3b82afdf03902dac3f3slive AllowOverride None<br />
80c4526970a11f37c0f8e3b82afdf03902dac3f3slive </Directory><br />
003f0c9fda6664daf5092a0e42f65ede20098153slive <Directory /home/><br />
003f0c9fda6664daf5092a0e42f65ede20098153slive AllowOverride FileInfo<br />
fb77c505254b6e9c925e23e734463e87574f8f40kess </Directory>
fb77c505254b6e9c925e23e734463e87574f8f40kess </example>
003f0c9fda6664daf5092a0e42f65ede20098153slive <p>for access to the document <code>/home/web/dir/doc.html</code>
003f0c9fda6664daf5092a0e42f65ede20098153slive the steps are:</p>
130d299c4b2b15be45532a176604c71fdc7bea5bnd <li>Apply directive <code>AllowOverride FileInfo</code> (for
a7f40ca49262952d6dd69d021cf5b0c2b452ae4cnd <code>/home/.htaccess</code>, <code>/home/web/.htaccess</code> and
a7f40ca49262952d6dd69d021cf5b0c2b452ae4cnd <p>Regular expressions are not considered until after all of the
fb77c505254b6e9c925e23e734463e87574f8f40kess normal sections have been applied. Then all of the regular
fb77c505254b6e9c925e23e734463e87574f8f40kess expressions are tested in the order they appeared in the
a7f40ca49262952d6dd69d021cf5b0c2b452ae4cnd configuration file. For example, with</p>
030108b1816bcda3d925df65357feabdce83bc94slive <Directory ~ abc$><br />
80c4526970a11f37c0f8e3b82afdf03902dac3f3slive # ... directives here ...<br />
a7f40ca49262952d6dd69d021cf5b0c2b452ae4cnd </Directory>
a7f40ca49262952d6dd69d021cf5b0c2b452ae4cnd </example>
a7f40ca49262952d6dd69d021cf5b0c2b452ae4cnd <p>the regular expression section won't be considered until after
fb77c505254b6e9c925e23e734463e87574f8f40kess all normal <directive type="section">Directory</directive>s and
fb77c505254b6e9c925e23e734463e87574f8f40kess <code>.htaccess</code> files have been applied. Then the regular
80c4526970a11f37c0f8e3b82afdf03902dac3f3slive expression will match on <code>/home/abc/public_html/abc</code> and
6b64034fa2a644ba291c484c0c01c7df5b8d982ckess the corresponding <directive type="section">Directory</directive> will
313bb560bc5c323cfd40c9cad7335b4b8e060aedkess be applied.</p>
80c4526970a11f37c0f8e3b82afdf03902dac3f3slive <code><Directory /></code> is <code>Allow from All</code>.
80c4526970a11f37c0f8e3b82afdf03902dac3f3slive This means that Apache httpd will serve any file mapped from an URL. It is
80c4526970a11f37c0f8e3b82afdf03902dac3f3slive recommended that you change this with a block such
130d299c4b2b15be45532a176604c71fdc7bea5bnd <Directory /><br />
130d299c4b2b15be45532a176604c71fdc7bea5bnd Order Deny,Allow<br />
130d299c4b2b15be45532a176604c71fdc7bea5bnd Deny from All<br />
130d299c4b2b15be45532a176604c71fdc7bea5bnd </Directory>
130d299c4b2b15be45532a176604c71fdc7bea5bnd </example>
a7f40ca49262952d6dd69d021cf5b0c2b452ae4cnd href="/misc/security_tips.html">Security Tips</a> page for more
80c4526970a11f37c0f8e3b82afdf03902dac3f3slive <p>The directory sections occur in the <code>httpd.conf</code> file.
80c4526970a11f37c0f8e3b82afdf03902dac3f3slive <directive type="section">Directory</directive> directives
80c4526970a11f37c0f8e3b82afdf03902dac3f3slive cannot nest, and cannot appear in a <directive module="core"
80c4526970a11f37c0f8e3b82afdf03902dac3f3slive type="section">Limit</directive> or <directive module="core"
80c4526970a11f37c0f8e3b82afdf03902dac3f3slive<seealso><a href="/sections.html">How <Directory>,
6b64034fa2a644ba291c484c0c01c7df5b8d982ckess <Location> and <Files> sections work</a> for an
80c4526970a11f37c0f8e3b82afdf03902dac3f3slive explanation of how these different sections are combined when a
313bb560bc5c323cfd40c9cad7335b4b8e060aedkess request is received</seealso>
6b64034fa2a644ba291c484c0c01c7df5b8d982ckess</directivesynopsis>
80c4526970a11f37c0f8e3b82afdf03902dac3f3slive<description>Enclose directives that apply to
80c4526970a11f37c0f8e3b82afdf03902dac3f3slivefile-system directories matching a regular expression.</description>
80c4526970a11f37c0f8e3b82afdf03902dac3f3slive... </DirectoryMatch></syntax>
80c4526970a11f37c0f8e3b82afdf03902dac3f3slive<contextlist><context>server config</context><context>virtual host</context>
130d299c4b2b15be45532a176604c71fdc7bea5bnd</contextlist>
130d299c4b2b15be45532a176604c71fdc7bea5bnd <p><directive type="section">DirectoryMatch</directive> and
130d299c4b2b15be45532a176604c71fdc7bea5bnd <code></DirectoryMatch></code> are used to enclose a group
130d299c4b2b15be45532a176604c71fdc7bea5bnd of directives which will apply only to the named directory,
a7f40ca49262952d6dd69d021cf5b0c2b452ae4cnd the same as <directive module="core" type="section">Directory</directive>.
80c4526970a11f37c0f8e3b82afdf03902dac3f3slive However, it takes as an argument a
313bb560bc5c323cfd40c9cad7335b4b8e060aedkess <glossary ref="regex">regular expression</glossary>. For example:</p>
6b64034fa2a644ba291c484c0c01c7df5b8d982ckess <DirectoryMatch "^/www/(.+/)?[0-9]{3}">
6b64034fa2a644ba291c484c0c01c7df5b8d982ckess </example>
80c4526970a11f37c0f8e3b82afdf03902dac3f3slive <p>would match directories in <code>/www/</code> that consisted of three
80c4526970a11f37c0f8e3b82afdf03902dac3f3slive numbers.</p>
80c4526970a11f37c0f8e3b82afdf03902dac3f3slive Prior to 2.3.9, this directive implicitly applied to sub-directories
80c4526970a11f37c0f8e3b82afdf03902dac3f3slive (like <directive module="core" type="section">Directory</directive>) and
80c4526970a11f37c0f8e3b82afdf03902dac3f3slive could not match the end of line symbol ($). In 2.3.9 and later,
130d299c4b2b15be45532a176604c71fdc7bea5bnd only directories that match the expression are affected by the enclosed
130d299c4b2b15be45532a176604c71fdc7bea5bnd directives.
130d299c4b2b15be45532a176604c71fdc7bea5bnd This directive applies to requests for directories that may or may
130d299c4b2b15be45532a176604c71fdc7bea5bnd not end in a trailing slash, so expressions that are anchored to the
a7f40ca49262952d6dd69d021cf5b0c2b452ae4cnd end of line ($) must be written with care.
80c4526970a11f37c0f8e3b82afdf03902dac3f3slive<seealso><directive type="section" module="core">Directory</directive> for
80c4526970a11f37c0f8e3b82afdf03902dac3f3slivea description of how regular expressions are mixed in with normal
fb77c505254b6e9c925e23e734463e87574f8f40kess<directive type="section">Directory</directive>s</seealso>
fb77c505254b6e9c925e23e734463e87574f8f40kesshref="/sections.html">How <Directory>, <Location> and
fb77c505254b6e9c925e23e734463e87574f8f40kess<Files> sections work</a> for an explanation of how these different
80c4526970a11f37c0f8e3b82afdf03902dac3f3slivesections are combined when a request is received</seealso>
80c4526970a11f37c0f8e3b82afdf03902dac3f3slive</directivesynopsis>
80c4526970a11f37c0f8e3b82afdf03902dac3f3slive<directivesynopsis>
313bb560bc5c323cfd40c9cad7335b4b8e060aedkess<description>Directory that forms the main document tree visible
80c4526970a11f37c0f8e3b82afdf03902dac3f3slivefrom the web</description>
80c4526970a11f37c0f8e3b82afdf03902dac3f3slive<syntax>DocumentRoot <var>directory-path</var></syntax>
80c4526970a11f37c0f8e3b82afdf03902dac3f3slive<default>DocumentRoot /usr/local/apache/htdocs</default>
80c4526970a11f37c0f8e3b82afdf03902dac3f3slive<contextlist><context>server config</context><context>virtual host</context>
80c4526970a11f37c0f8e3b82afdf03902dac3f3slive</contextlist>
15ba1801088da1aad6d20609cf3f7b0b1eefce8aslive <p>This directive sets the directory from which <program>httpd</program>
80c4526970a11f37c0f8e3b82afdf03902dac3f3slive will serve files. Unless matched by a directive like <directive
a7f40ca49262952d6dd69d021cf5b0c2b452ae4cnd module="mod_alias">Alias</directive>, the server appends the
7b5535ed88e0f561b3bfb3330137bd804846afd4slive path from the requested URL to the document root to make the
80c4526970a11f37c0f8e3b82afdf03902dac3f3slive path to the document. Example:</p>
80c4526970a11f37c0f8e3b82afdf03902dac3f3slive <p>then an access to
80c4526970a11f37c0f8e3b82afdf03902dac3f3slive <code>http://www.my.host.com/index.html</code> refers to
80c4526970a11f37c0f8e3b82afdf03902dac3f3slive <code>/usr/web/index.html</code>. If the <var>directory-path</var> is
030108b1816bcda3d925df65357feabdce83bc94slive not absolute then it is assumed to be relative to the <directive
a7f40ca49262952d6dd69d021cf5b0c2b452ae4cnd <p>The <directive>DocumentRoot</directive> should be specified without
6954edc623ca2c179eb5b33e97e4304d06fd649frbowen a trailing slash.</p>
80c4526970a11f37c0f8e3b82afdf03902dac3f3slive<seealso><a href="/urlmapping.html#documentroot">Mapping URLs to Filesystem
80c4526970a11f37c0f8e3b82afdf03902dac3f3slive</directivesynopsis>
80c4526970a11f37c0f8e3b82afdf03902dac3f3slive<directivesynopsis>
313bb560bc5c323cfd40c9cad7335b4b8e060aedkess<description>Use memory-mapping to read files during delivery</description>
313bb560bc5c323cfd40c9cad7335b4b8e060aedkess<contextlist><context>server config</context><context>virtual host</context>
313bb560bc5c323cfd40c9cad7335b4b8e060aedkess<context>directory</context><context>.htaccess</context>
80c4526970a11f37c0f8e3b82afdf03902dac3f3slive</contextlist>
003f0c9fda6664daf5092a0e42f65ede20098153slive <p>This directive controls whether the <program>httpd</program> may use
80c4526970a11f37c0f8e3b82afdf03902dac3f3slive memory-mapping if it needs to read the contents of a file during
a7f40ca49262952d6dd69d021cf5b0c2b452ae4cnd delivery. By default, when the handling of a request requires
80c4526970a11f37c0f8e3b82afdf03902dac3f3slive access to the data within a file -- for example, when delivering a
80c4526970a11f37c0f8e3b82afdf03902dac3f3slive server-parsed file using <module>mod_include</module> -- Apache httpd
80c4526970a11f37c0f8e3b82afdf03902dac3f3slive memory-maps the file if the OS supports it.</p>
80c4526970a11f37c0f8e3b82afdf03902dac3f3slive <p>This memory-mapping sometimes yields a performance improvement.
a1ef40892ffa2b44fc249423c5b6c42a74a84c68nd But in some environments, it is better to disable the memory-mapping
fb77c505254b6e9c925e23e734463e87574f8f40kess to prevent operational problems:</p>
fb77c505254b6e9c925e23e734463e87574f8f40kess <li>On some multiprocessor systems, memory-mapping can reduce the
a7f40ca49262952d6dd69d021cf5b0c2b452ae4cnd <li>Deleting or truncating a file while <program>httpd</program>
a7f40ca49262952d6dd69d021cf5b0c2b452ae4cnd has it memory-mapped can cause <program>httpd</program> to
a7f40ca49262952d6dd69d021cf5b0c2b452ae4cnd crash with a segmentation fault.
c68acc9d712af079afa2bd1a5a4aeef9a3ea573ckess <p>For server configurations that are vulnerable to these problems,
c68acc9d712af079afa2bd1a5a4aeef9a3ea573ckess you should disable memory-mapping of delivered files by specifying:</p>
80c4526970a11f37c0f8e3b82afdf03902dac3f3slive EnableMMAP Off
1b01d1ee11c612226cb3141eed4581dc179266c1rbowen <p>For NFS mounted files, this feature may be disabled explicitly for
1b01d1ee11c612226cb3141eed4581dc179266c1rbowen the offending files by specifying:</p>
af18698b10b429b270551ca3a5d51a75e1c9db22brianp <Directory "/path-to-nfs-files">
003f0c9fda6664daf5092a0e42f65ede20098153slive EnableMMAP Off
fb77c505254b6e9c925e23e734463e87574f8f40kess </Directory>
af18698b10b429b270551ca3a5d51a75e1c9db22brianp</directivesynopsis>
af18698b10b429b270551ca3a5d51a75e1c9db22brianp<directivesynopsis>
a1ef40892ffa2b44fc249423c5b6c42a74a84c68nd<description>Use the kernel sendfile support to deliver files to the client</description>
fb77c505254b6e9c925e23e734463e87574f8f40kess<contextlist><context>server config</context><context>virtual host</context>
fb77c505254b6e9c925e23e734463e87574f8f40kess<context>directory</context><context>.htaccess</context>
a7f40ca49262952d6dd69d021cf5b0c2b452ae4cnd</contextlist>
a7f40ca49262952d6dd69d021cf5b0c2b452ae4cnd<compatibility>Available in version 2.0.44 and later. Default changed to Off in
af18698b10b429b270551ca3a5d51a75e1c9db22brianpversion 2.3.9.</compatibility>
af18698b10b429b270551ca3a5d51a75e1c9db22brianp <p>This directive controls whether <program>httpd</program> may use the
af18698b10b429b270551ca3a5d51a75e1c9db22brianp sendfile support from the kernel to transmit file contents to the client.
a1ef40892ffa2b44fc249423c5b6c42a74a84c68nd By default, when the handling of a request requires no access
af18698b10b429b270551ca3a5d51a75e1c9db22brianp to the data within a file -- for example, when delivering a
a1ef40892ffa2b44fc249423c5b6c42a74a84c68nd static file -- Apache httpd uses sendfile to deliver the file contents
a1ef40892ffa2b44fc249423c5b6c42a74a84c68nd without ever reading the file if the OS supports it.</p>
af18698b10b429b270551ca3a5d51a75e1c9db22brianp <p>This sendfile mechanism avoids separate read and send operations,
a7f40ca49262952d6dd69d021cf5b0c2b452ae4cnd and buffer allocations. But on some platforms or within some
a7f40ca49262952d6dd69d021cf5b0c2b452ae4cnd filesystems, it is better to disable this feature to avoid
a7f40ca49262952d6dd69d021cf5b0c2b452ae4cnd operational problems:</p>
fb77c505254b6e9c925e23e734463e87574f8f40kess <li>Some platforms may have broken sendfile support that the build
a7f40ca49262952d6dd69d021cf5b0c2b452ae4cnd system did not detect, especially if the binaries were built on
41ef8b3051855b802104193ee0a587515af60a37wrowe another box and moved to such a machine with broken sendfile
41ef8b3051855b802104193ee0a587515af60a37wrowe support.</li>
41ef8b3051855b802104193ee0a587515af60a37wrowe <li>On Linux the use of sendfile triggers TCP-checksum
41ef8b3051855b802104193ee0a587515af60a37wrowe offloading bugs on certain networking cards when using IPv6.</li>
41ef8b3051855b802104193ee0a587515af60a37wrowe <li>On Linux on Itanium, sendfile may be unable to handle files
41ef8b3051855b802104193ee0a587515af60a37wrowe over 2GB in size.</li>
313bb560bc5c323cfd40c9cad7335b4b8e060aedkess module="core">DocumentRoot</directive> (e.g., NFS, SMB, CIFS, FUSE),
313bb560bc5c323cfd40c9cad7335b4b8e060aedkess the kernel may be unable to serve the network file through
41ef8b3051855b802104193ee0a587515af60a37wrowe its own cache.</li>
41ef8b3051855b802104193ee0a587515af60a37wrowe <p>For server configurations that are not vulnerable to these problems,
41ef8b3051855b802104193ee0a587515af60a37wrowe you may enable this feature by specifying:</p>
41ef8b3051855b802104193ee0a587515af60a37wrowe EnableSendfile On
fb77c505254b6e9c925e23e734463e87574f8f40kess </example>
41ef8b3051855b802104193ee0a587515af60a37wrowe <p>For network mounted files, this feature may be disabled explicitly
41ef8b3051855b802104193ee0a587515af60a37wrowe for the offending files by specifying:</p>
9fb925624300c864fe3969a264e52aa83f3c2dd0slive <Directory "/path-to-nfs-files">
41ef8b3051855b802104193ee0a587515af60a37wrowe EnableSendfile Off
a1ef40892ffa2b44fc249423c5b6c42a74a84c68nd </Directory>
41ef8b3051855b802104193ee0a587515af60a37wrowe <p>Please note that the per-directory and .htaccess configuration
41ef8b3051855b802104193ee0a587515af60a37wrowe of <directive>EnableSendfile</directive> is not supported by
41ef8b3051855b802104193ee0a587515af60a37wrowe Only global definition of <directive>EnableSendfile</directive>
9b5e2c5e769dc678a1aca06df75c32022b2f1492trawick is taken into account by the module.
41ef8b3051855b802104193ee0a587515af60a37wrowe</directivesynopsis>
41ef8b3051855b802104193ee0a587515af60a37wrowe<directivesynopsis>
41ef8b3051855b802104193ee0a587515af60a37wrowe<description>What the server will return to the client
9fb925624300c864fe3969a264e52aa83f3c2dd0slivein case of an error</description>
313bb560bc5c323cfd40c9cad7335b4b8e060aedkess<syntax>ErrorDocument <var>error-code</var> <var>document</var></syntax>
78f4d313fd5edf76dc5cfb8725e082a08cd29740jwoolley<contextlist><context>server config</context><context>virtual host</context>
78f4d313fd5edf76dc5cfb8725e082a08cd29740jwoolley<context>directory</context><context>.htaccess</context>
9d00e5d0f270651f1f1cc1abea03bf53e5656fcecolm</contextlist>
9fb925624300c864fe3969a264e52aa83f3c2dd0slive<compatibility>Quoting syntax for text messages is different in Apache HTTP Server
313bb560bc5c323cfd40c9cad7335b4b8e060aedkess2.0</compatibility>
41ef8b3051855b802104193ee0a587515af60a37wrowe <p>In the event of a problem or error, Apache httpd can be configured
41ef8b3051855b802104193ee0a587515af60a37wrowe to do one of four things,</p>
41ef8b3051855b802104193ee0a587515af60a37wrowe <li>redirect to a local <var>URL-path</var> to handle the
41ef8b3051855b802104193ee0a587515af60a37wrowe <li>redirect to an external <var>URL</var> to handle the
313bb560bc5c323cfd40c9cad7335b4b8e060aedkess <p>The first option is the default, while options 2-4 are
313bb560bc5c323cfd40c9cad7335b4b8e060aedkess configured using the <directive>ErrorDocument</directive>
41ef8b3051855b802104193ee0a587515af60a37wrowe directive, which is followed by the HTTP response code and a URL
41ef8b3051855b802104193ee0a587515af60a37wrowe or a message. Apache httpd will sometimes offer additional information
af18698b10b429b270551ca3a5d51a75e1c9db22brianp <p>URLs can begin with a slash (/) for local web-paths (relative
80c4526970a11f37c0f8e3b82afdf03902dac3f3slive to the <directive module="core">DocumentRoot</directive>), or be a
80c4526970a11f37c0f8e3b82afdf03902dac3f3slive full URL which the client can resolve. Alternatively, a message
003f0c9fda6664daf5092a0e42f65ede20098153slive can be provided to be displayed by the browser. Examples:</p>
80c4526970a11f37c0f8e3b82afdf03902dac3f3slive ErrorDocument 500 http://foo.example.com/cgi-bin/tester<br />
80c4526970a11f37c0f8e3b82afdf03902dac3f3slive ErrorDocument 403 "Sorry can't allow you access today"
80c4526970a11f37c0f8e3b82afdf03902dac3f3slive <p>Additionally, the special value <code>default</code> can be used
80c4526970a11f37c0f8e3b82afdf03902dac3f3slive to specify Apache httpd's simple hardcoded message. While not required
80c4526970a11f37c0f8e3b82afdf03902dac3f3slive under normal circumstances, <code>default</code> will restore
80c4526970a11f37c0f8e3b82afdf03902dac3f3slive Apache httpd's simple hardcoded message for configurations that would
80c4526970a11f37c0f8e3b82afdf03902dac3f3slive otherwise inherit an existing <directive>ErrorDocument</directive>.</p>
a7f40ca49262952d6dd69d021cf5b0c2b452ae4cnd ErrorDocument 404 default<br />
80c4526970a11f37c0f8e3b82afdf03902dac3f3slive </Directory>
a7f40ca49262952d6dd69d021cf5b0c2b452ae4cnd </example>
80c4526970a11f37c0f8e3b82afdf03902dac3f3slive <p>Note that when you specify an <directive>ErrorDocument</directive>
80c4526970a11f37c0f8e3b82afdf03902dac3f3slive that points to a remote URL (ie. anything with a method such as
80c4526970a11f37c0f8e3b82afdf03902dac3f3slive <code>http</code> in front of it), Apache HTTP Server will send a redirect to the
80c4526970a11f37c0f8e3b82afdf03902dac3f3slive client to tell it where to find the document, even if the
80c4526970a11f37c0f8e3b82afdf03902dac3f3slive document ends up being on the same server. This has several
80c4526970a11f37c0f8e3b82afdf03902dac3f3slive implications, the most important being that the client will not
80c4526970a11f37c0f8e3b82afdf03902dac3f3slive receive the original error status code, but instead will
80c4526970a11f37c0f8e3b82afdf03902dac3f3slive receive a redirect status code. This in turn can confuse web
69fba5b8aa0b0dc408f649cfdaab064ce120b05bslive robots and other clients which try to determine if a URL is
69fba5b8aa0b0dc408f649cfdaab064ce120b05bslive valid using the status code. In addition, if you use a remote
69fba5b8aa0b0dc408f649cfdaab064ce120b05bslive URL in an <code>ErrorDocument 401</code>, the client will not
69fba5b8aa0b0dc408f649cfdaab064ce120b05bslive know to prompt the user for a password since it will not
80c4526970a11f37c0f8e3b82afdf03902dac3f3slive receive the 401 status code. Therefore, <strong>if you use an
a7f40ca49262952d6dd69d021cf5b0c2b452ae4cnd <code>ErrorDocument 401</code> directive then it must refer to a local
a7f40ca49262952d6dd69d021cf5b0c2b452ae4cnd <p>Microsoft Internet Explorer (MSIE) will by default ignore
a7f40ca49262952d6dd69d021cf5b0c2b452ae4cnd server-generated error messages when they are "too small" and substitute
a7f40ca49262952d6dd69d021cf5b0c2b452ae4cnd its own "friendly" error messages. The size threshold varies depending on
80c4526970a11f37c0f8e3b82afdf03902dac3f3slive the type of error, but in general, if you make your error document
f7fe99050600166042c04b8e595fb75499eed7f0geoff greater than 512 bytes, then MSIE will show the server-generated
f7fe99050600166042c04b8e595fb75499eed7f0geoff error rather than masking it. More information is available in
f7fe99050600166042c04b8e595fb75499eed7f0geoff Microsoft Knowledge Base article <a
f7fe99050600166042c04b8e595fb75499eed7f0geoff href="http://support.microsoft.com/default.aspx?scid=kb;en-us;Q294807"
f7fe99050600166042c04b8e595fb75499eed7f0geoff <p>Although most error messages can be overriden, there are certain
f7fe99050600166042c04b8e595fb75499eed7f0geoff circumstances where the internal messages are used regardless of the
f7fe99050600166042c04b8e595fb75499eed7f0geoff setting of <directive module="core">ErrorDocument</directive>. In
f7fe99050600166042c04b8e595fb75499eed7f0geoff particular, if a malformed request is detected, normal request processing
f7fe99050600166042c04b8e595fb75499eed7f0geoff will be immediately halted and the internal error message returned.
f7fe99050600166042c04b8e595fb75499eed7f0geoff This is necessary to guard against security problems caused by
f7fe99050600166042c04b8e595fb75499eed7f0geoff bad requests.</p>
f7fe99050600166042c04b8e595fb75499eed7f0geoff <p>If you are using mod_proxy, you may wish to enable
80c4526970a11f37c0f8e3b82afdf03902dac3f3slive <directive module="mod_proxy">ProxyErrorOverride</directive> so that you can provide
80c4526970a11f37c0f8e3b82afdf03902dac3f3slive custom error messages on behalf of your Origin servers. If you don't enable ProxyErrorOverride,
fb77c505254b6e9c925e23e734463e87574f8f40kess Apache httpd will not generate custom error documents for proxied content.</p>
80c4526970a11f37c0f8e3b82afdf03902dac3f3slive</directivesynopsis>
80c4526970a11f37c0f8e3b82afdf03902dac3f3slive<directivesynopsis>
80c4526970a11f37c0f8e3b82afdf03902dac3f3slive<description>Location where the server will log errors</description>
80c4526970a11f37c0f8e3b82afdf03902dac3f3slive<syntax> ErrorLog <var>file-path</var>|syslog[:<var>facility</var>]</syntax>
313bb560bc5c323cfd40c9cad7335b4b8e060aedkess<default>ErrorLog logs/error_log (Unix) ErrorLog logs/error.log (Windows and OS/2)</default>
80c4526970a11f37c0f8e3b82afdf03902dac3f3slive<contextlist><context>server config</context><context>virtual host</context>
80c4526970a11f37c0f8e3b82afdf03902dac3f3slive</contextlist>
fb77c505254b6e9c925e23e734463e87574f8f40kess <p>The <directive>ErrorLog</directive> directive sets the name of
4f854c24127e28f7ad72ce9a39d4448aaf910fc1slive the file to which the server will log any errors it encounters. If
4f854c24127e28f7ad72ce9a39d4448aaf910fc1slive the <var>file-path</var> is not absolute then it is assumed to be
4f854c24127e28f7ad72ce9a39d4448aaf910fc1slive relative to the <directive module="core">ServerRoot</directive>.</p>
69fba5b8aa0b0dc408f649cfdaab064ce120b05bslive begins with a pipe character "<code>|</code>" then it is assumed to be a
69fba5b8aa0b0dc408f649cfdaab064ce120b05bslive command to spawn to handle the error log.</p>
80c4526970a11f37c0f8e3b82afdf03902dac3f3slive <p>See the notes on <a href="/logs.html#piped">piped logs</a> for
80c4526970a11f37c0f8e3b82afdf03902dac3f3slive more information.</p>
80c4526970a11f37c0f8e3b82afdf03902dac3f3slive <p>Using <code>syslog</code> instead of a filename enables logging
80c4526970a11f37c0f8e3b82afdf03902dac3f3slive via syslogd(8) if the system supports it. The default is to use
80c4526970a11f37c0f8e3b82afdf03902dac3f3slive syslog facility <code>local7</code>, but you can override this by
80c4526970a11f37c0f8e3b82afdf03902dac3f3slive using the <code>syslog:<var>facility</var></code> syntax where
80c4526970a11f37c0f8e3b82afdf03902dac3f3slive <var>facility</var> can be one of the names usually documented in
80c4526970a11f37c0f8e3b82afdf03902dac3f3slive syslog(1).</p>
3209c0009829fcf63b6213fb9c43d534f7906006slive ErrorLog syslog:user
80c4526970a11f37c0f8e3b82afdf03902dac3f3slive href="/misc/security_tips.html#serverroot">security tips</a>
80c4526970a11f37c0f8e3b82afdf03902dac3f3slive document for details on why your security could be compromised
80c4526970a11f37c0f8e3b82afdf03902dac3f3slive if the directory where log files are stored is writable by
c68acc9d712af079afa2bd1a5a4aeef9a3ea573ckess anyone other than the user that starts the server.</p>
fb109b84906e3ee61680aa289953c2f9e859354erbowen <p>When entering a file path on non-Unix platforms, care should be taken
fb109b84906e3ee61680aa289953c2f9e859354erbowen to make sure that only forward slashed are used even though the platform
fb109b84906e3ee61680aa289953c2f9e859354erbowen may allow the use of back slashes. In general it is a good idea to always
fb109b84906e3ee61680aa289953c2f9e859354erbowen use forward slashes throughout the configuration files.</p>
80c4526970a11f37c0f8e3b82afdf03902dac3f3slive<seealso><directive module="core">LogLevel</directive></seealso>
80c4526970a11f37c0f8e3b82afdf03902dac3f3slive<seealso><a href="/logs.html">Apache HTTP Server Log Files</a></seealso>
80c4526970a11f37c0f8e3b82afdf03902dac3f3slive</directivesynopsis>
fb109b84906e3ee61680aa289953c2f9e859354erbowen<directivesynopsis>
fb109b84906e3ee61680aa289953c2f9e859354erbowen<description>Format specification for error log entries</description>
80c4526970a11f37c0f8e3b82afdf03902dac3f3slive<syntax> ErrorLog [connection|request] <var>format</var></syntax>
80c4526970a11f37c0f8e3b82afdf03902dac3f3slive<contextlist><context>server config</context><context>virtual host</context>
80c4526970a11f37c0f8e3b82afdf03902dac3f3slive</contextlist>
a7f40ca49262952d6dd69d021cf5b0c2b452ae4cnd<compatibility>Available in Apache httpd 2.3.9 and later</compatibility>
80c4526970a11f37c0f8e3b82afdf03902dac3f3slive <p><directive>ErrorLogFormat</directive> allows to specify what
fb109b84906e3ee61680aa289953c2f9e859354erbowen supplementary information is logged in the error log in addition to the
fb109b84906e3ee61680aa289953c2f9e859354erbowen actual log message.</p>
80c4526970a11f37c0f8e3b82afdf03902dac3f3slive ErrorLogFormat "[%t] [%l] [pid %P] %F: %E: [client %a] %M"
9b5e2c5e769dc678a1aca06df75c32022b2f1492trawick <p>Specifying <code>connection</code> or <code>request</code> as first
80c4526970a11f37c0f8e3b82afdf03902dac3f3slive paramter allows to specify additional formats, causing additional
2bac697634d965d9d9a921a99a68b2c454c8a95dbnicholes information to be logged when the first message is logged for a specific
2bac697634d965d9d9a921a99a68b2c454c8a95dbnicholes connection or request, respectivly. This additional information is only
2bac697634d965d9d9a921a99a68b2c454c8a95dbnicholes logged once per connection/request. If a connection or request is processed
2bac697634d965d9d9a921a99a68b2c454c8a95dbnicholes without causing any log message, the additional information is not logged
80c4526970a11f37c0f8e3b82afdf03902dac3f3slive <p>It can happen that some format string items do not produce output. For
80c4526970a11f37c0f8e3b82afdf03902dac3f3slive example, the Referer header is only present if the log message is
80c4526970a11f37c0f8e3b82afdf03902dac3f3slive associated to a request and the log message happens at a time when the
80c4526970a11f37c0f8e3b82afdf03902dac3f3slive Referer header has already been read from the client. If no output is
80c4526970a11f37c0f8e3b82afdf03902dac3f3slive produced, the default behaviour is to delete everything from the preceeding
80c4526970a11f37c0f8e3b82afdf03902dac3f3slive space character to the next space character. This means the log line is
80c4526970a11f37c0f8e3b82afdf03902dac3f3slive implicitly divided into fields on non-whitespace to whitespace transitions.
003f0c9fda6664daf5092a0e42f65ede20098153slive If a format string item does not produce output, the whole field is
80c4526970a11f37c0f8e3b82afdf03902dac3f3slive ommitted. For example, if the remote address <code>%a</code> in the log
a7f40ca49262952d6dd69d021cf5b0c2b452ae4cnd format <code>[%t] [%l] [%a] %M </code> is not available, the surrounding
18b4b0fd6056093002ddef488636bf5ebe415ef0erikabele brackets are not logged either. Space characters can be escaped with a
80c4526970a11f37c0f8e3b82afdf03902dac3f3slive backslash to prevent them from delimiting a field. The combination '% '
80c4526970a11f37c0f8e3b82afdf03902dac3f3slive (percent space) is a zero-witdh field delimiter that does not produce any
80c4526970a11f37c0f8e3b82afdf03902dac3f3slive output.</p>
80c4526970a11f37c0f8e3b82afdf03902dac3f3slive <p>The above behaviour can be changed by adding modifiers to the format
80c4526970a11f37c0f8e3b82afdf03902dac3f3slive string item. A <code>-</code> (minus) modifier causes a minus to be logged if the
80c4526970a11f37c0f8e3b82afdf03902dac3f3slive respective item does not produce any output. In once-per-connection/request
80c4526970a11f37c0f8e3b82afdf03902dac3f3slive formats, it is also possible to use the <code>+</code> (plus) modifier. If an
fb77c505254b6e9c925e23e734463e87574f8f40kess item with the plus modifier does not produce any output, the whole line is
fb77c505254b6e9c925e23e734463e87574f8f40kess ommitted.</p>
fb77c505254b6e9c925e23e734463e87574f8f40kess <p>A number as modifier can be used to assign a log severity level to a
fb77c505254b6e9c925e23e734463e87574f8f40kess format item. The item will only be logged if the severity of the log
fb77c505254b6e9c925e23e734463e87574f8f40kess message is not higher than the specified log severity level. The number can
fb77c505254b6e9c925e23e734463e87574f8f40kess range from 1 (alert) over 4 (warn) and 7 (debug) to 15 (trace8).</p>
80c4526970a11f37c0f8e3b82afdf03902dac3f3slive <p>Some format string items accept additional parameters in braces.</p>
530eba85dbd41b8a0fa5255d3648d1440199a661slive <columnspec><column width=".2"/><column width=".8"/></columnspec>
530eba85dbd41b8a0fa5255d3648d1440199a661slive <tr><th>Format String</th> <th>Description</th></tr>
a7f40ca49262952d6dd69d021cf5b0c2b452ae4cnd <td>Request environment variable <code>name</code></td></tr>
a7f40ca49262952d6dd69d021cf5b0c2b452ae4cnd <td>Source file name and line number of the log call</td></tr>
0db981f8fdfb62c5149efa079f0369b73d472d04rpluem <td>Number of keep-alive requests on this connection</td></tr>
80c4526970a11f37c0f8e3b82afdf03902dac3f3slive <td>Log ID of the connection if used in connection scope, empty otherwise</td></tr>
80c4526970a11f37c0f8e3b82afdf03902dac3f3slive <td>The current time including micro-seconds</td></tr>
80c4526970a11f37c0f8e3b82afdf03902dac3f3slive <td>The current time in compact ISO 8601 format, including
a7f40ca49262952d6dd69d021cf5b0c2b452ae4cnd <td>The canonical <directive module="core">ServerName</directive>
030108b1816bcda3d925df65357feabdce83bc94slive <td>The server name of the server serving the request according to the
80c4526970a11f37c0f8e3b82afdf03902dac3f3slive <directive module="core" >UseCanonicalName</directive>
80c4526970a11f37c0f8e3b82afdf03902dac3f3slive <p>The log ID format <code>%L</code> produces a unique id for a connection
80c4526970a11f37c0f8e3b82afdf03902dac3f3slive or request. This can be used to correlate which log lines belong to the
80c4526970a11f37c0f8e3b82afdf03902dac3f3slive same connection or request, which request happens on which connection.
fb77c505254b6e9c925e23e734463e87574f8f40kess <module>mod_log_config</module>, to allow to correlate access log entries
fb77c505254b6e9c925e23e734463e87574f8f40kess with error log lines. If <module>mod_unique_id</module> is loaded, its
80c4526970a11f37c0f8e3b82afdf03902dac3f3slive unique id will be used as log ID for requests.</p>
313bb560bc5c323cfd40c9cad7335b4b8e060aedkess <example><title>Example (somewhat similar to default format)</title>
313bb560bc5c323cfd40c9cad7335b4b8e060aedkess ErrorLogFormat "[%{u}t] [%-m:%l] [pid %P] %7F: %E: [client\ %a]
313bb560bc5c323cfd40c9cad7335b4b8e060aedkess %M% ,\ referer\ %{Referer}i"
80c4526970a11f37c0f8e3b82afdf03902dac3f3slive <example><title>Example (similar to the 2.2.x format)</title>
80c4526970a11f37c0f8e3b82afdf03902dac3f3slive ErrorLogFormat "[%t] [%l] %7F: %E: [client\ %a]
003f0c9fda6664daf5092a0e42f65ede20098153slive %M% ,\ referer\ %{Referer}i"
80c4526970a11f37c0f8e3b82afdf03902dac3f3slive <example><title>Advanced example with request/connection log IDs</title>
80c4526970a11f37c0f8e3b82afdf03902dac3f3slive ErrorLogFormat "[%{uc}t] [%-m:%-l] [R:%L] [C:%{C}L] %7F: %E: %M"<br/>
80c4526970a11f37c0f8e3b82afdf03902dac3f3slive ErrorLogFormat request "[%{uc}t] [R:%L] Request %k on C:%{c}L pid:%P tid:%T"<br/>
003f0c9fda6664daf5092a0e42f65ede20098153slive ErrorLogFormat request "[%{uc}t] [R:%L] UA:'%+{User-Agent}i'"<br/>
80c4526970a11f37c0f8e3b82afdf03902dac3f3slive ErrorLogFormat request "[%{uc}t] [R:%L] Referer:'%+{Referer}i'"<br/>
80c4526970a11f37c0f8e3b82afdf03902dac3f3slive ErrorLogFormat connection "[%{uc}t] [C:%{c}L] local\ %a remote\ %A"<br/>
030108b1816bcda3d925df65357feabdce83bc94slive<seealso><directive module="core">ErrorLog</directive></seealso>
030108b1816bcda3d925df65357feabdce83bc94slive<seealso><directive module="core">LogLevel</directive></seealso>
a7f40ca49262952d6dd69d021cf5b0c2b452ae4cnd<seealso><a href="/logs.html">Apache HTTP Server Log Files</a></seealso>
a7f40ca49262952d6dd69d021cf5b0c2b452ae4cnd</directivesynopsis>
a7f40ca49262952d6dd69d021cf5b0c2b452ae4cnd<directivesynopsis>
80c4526970a11f37c0f8e3b82afdf03902dac3f3slive<description>Keep track of extended status information for each
80c4526970a11f37c0f8e3b82afdf03902dac3f3sliverequest</description>
313bb560bc5c323cfd40c9cad7335b4b8e060aedkess<contextlist><context>server config</context></contextlist>
80c4526970a11f37c0f8e3b82afdf03902dac3f3slive <p>This option tracks additional data per worker about the
80c4526970a11f37c0f8e3b82afdf03902dac3f3slive currently executing request, and a utilization summary; you
80c4526970a11f37c0f8e3b82afdf03902dac3f3slive can see these variables during runtime by configuring
80c4526970a11f37c0f8e3b82afdf03902dac3f3slive <module>mod_status</module>. Note that other modules may
80c4526970a11f37c0f8e3b82afdf03902dac3f3slive rely on this scoreboard.</p>
80c4526970a11f37c0f8e3b82afdf03902dac3f3slive <p>This setting applies to the entire server, and cannot be
80c4526970a11f37c0f8e3b82afdf03902dac3f3slive enabled or disabled on a virtualhost-by-virtualhost basis.
003f0c9fda6664daf5092a0e42f65ede20098153slive The collection of extended status information can slow down
80c4526970a11f37c0f8e3b82afdf03902dac3f3slive the server. Also note that this setting cannot be changed
80c4526970a11f37c0f8e3b82afdf03902dac3f3slive during a graceful restart.</p>
80c4526970a11f37c0f8e3b82afdf03902dac3f3slive <p>Note that loading <module>mod_status</module> will change
fb77c505254b6e9c925e23e734463e87574f8f40kess the default behavior to ExtendedStatus On, while other
80c4526970a11f37c0f8e3b82afdf03902dac3f3slive third party modules may do the same. Such modules rely on
80c4526970a11f37c0f8e3b82afdf03902dac3f3slive collecting detailed information about the state of all workers.
80c4526970a11f37c0f8e3b82afdf03902dac3f3slive The default is changed by <module>mod_status</module> beginning
a7f40ca49262952d6dd69d021cf5b0c2b452ae4cnd with version 2.3.6; the previous default was always Off.</p>
a7f40ca49262952d6dd69d021cf5b0c2b452ae4cnd</directivesynopsis>
80c4526970a11f37c0f8e3b82afdf03902dac3f3slive<directivesynopsis>
80c4526970a11f37c0f8e3b82afdf03902dac3f3slive<description>File attributes used to create the ETag
80c4526970a11f37c0f8e3b82afdf03902dac3f3sliveHTTP response header for static files</description>
c97e8972ab1f4dd167e3dc4db87daf91114009fbnd<contextlist><context>server config</context><context>virtual host</context>
7654193c1faf603feec999850322ad79e6c551bcnd</contextlist>
7654193c1faf603feec999850322ad79e6c551bcnd The <directive>FileETag</directive> directive configures the file
7654193c1faf603feec999850322ad79e6c551bcnd attributes that are used to create the <code>ETag</code> (entity
7654193c1faf603feec999850322ad79e6c551bcnd tag) response header field when the document is based on a static file.
7654193c1faf603feec999850322ad79e6c551bcnd (The <code>ETag</code> value is used in cache management to save
7654193c1faf603feec999850322ad79e6c551bcnd network bandwidth.) The
7654193c1faf603feec999850322ad79e6c551bcnd <directive>FileETag</directive> directive allows you to choose
c97e8972ab1f4dd167e3dc4db87daf91114009fbnd which of these -- if any -- should be used. The recognized keywords are:
80c4526970a11f37c0f8e3b82afdf03902dac3f3slive <dd>The file's i-node number will be included in the calculation</dd>
80c4526970a11f37c0f8e3b82afdf03902dac3f3slive <dd>The date and time the file was last modified will be included</dd>
80c4526970a11f37c0f8e3b82afdf03902dac3f3slive <dd>The number of bytes in the file will be included</dd>
fb77c505254b6e9c925e23e734463e87574f8f40kess <dd>All available fields will be used. This is equivalent to:
80c4526970a11f37c0f8e3b82afdf03902dac3f3slive <dd>If a document is file-based, no <code>ETag</code> field will be
80c4526970a11f37c0f8e3b82afdf03902dac3f3slive included in the response</dd>
fb77c505254b6e9c925e23e734463e87574f8f40kess <p>The <code>INode</code>, <code>MTime</code>, and <code>Size</code>
313bb560bc5c323cfd40c9cad7335b4b8e060aedkess keywords may be prefixed with either <code>+</code> or <code>-</code>,
9b5e2c5e769dc678a1aca06df75c32022b2f1492trawick which allow changes to be made to the default setting inherited
80c4526970a11f37c0f8e3b82afdf03902dac3f3slive from a broader scope. Any keyword appearing without such a prefix
80c4526970a11f37c0f8e3b82afdf03902dac3f3slive immediately and completely cancels the inherited setting.</p>
80c4526970a11f37c0f8e3b82afdf03902dac3f3slive <p>If a directory's configuration includes
9ed9eaf871c58d281af02e76125ceadb5060afa5nd <code>FileETag INode MTime Size</code>, and a
80c4526970a11f37c0f8e3b82afdf03902dac3f3slive subdirectory's includes <code>FileETag -INode</code>,
80c4526970a11f37c0f8e3b82afdf03902dac3f3slive the setting for that subdirectory (which will be inherited by
80c4526970a11f37c0f8e3b82afdf03902dac3f3slive any sub-subdirectories that don't override it) will be equivalent to
80c4526970a11f37c0f8e3b82afdf03902dac3f3slive Do not change the default for directories or locations that have WebDAV
80c4526970a11f37c0f8e3b82afdf03902dac3f3slive enabled and use <module>mod_dav_fs</module> as a storage provider.
80c4526970a11f37c0f8e3b82afdf03902dac3f3slive <module>mod_dav_fs</module> uses <code>INode MTime Size</code>
80c4526970a11f37c0f8e3b82afdf03902dac3f3slive as a fixed format for <code>ETag</code> comparisons on conditional requests.
fb77c505254b6e9c925e23e734463e87574f8f40kess These conditional requests will break if the <code>ETag</code> format is
80c4526970a11f37c0f8e3b82afdf03902dac3f3slive An ETag is not generated for responses parsed by <module>mod_include</module>,
fb77c505254b6e9c925e23e734463e87574f8f40kess since the response entity can change without a change of the INode, MTime, or Size
a1ef40892ffa2b44fc249423c5b6c42a74a84c68nd of the static file with embedded SSI directives.
80c4526970a11f37c0f8e3b82afdf03902dac3f3slive</directivesynopsis>
750d12c59545dbbac70390988de94f7e901b08f2niq<description>Contains directives that apply to matched
750d12c59545dbbac70390988de94f7e901b08f2niqfilenames</description>
750d12c59545dbbac70390988de94f7e901b08f2niq<syntax><Files <var>filename</var>> ... </Files></syntax>
750d12c59545dbbac70390988de94f7e901b08f2niq<contextlist><context>server config</context><context>virtual host</context>
750d12c59545dbbac70390988de94f7e901b08f2niq</contextlist>
750d12c59545dbbac70390988de94f7e901b08f2niq <p>The <directive type="section">Files</directive> directive
750d12c59545dbbac70390988de94f7e901b08f2niq limits the scope of the enclosed directives by filename. It is comparable
750d12c59545dbbac70390988de94f7e901b08f2niq to the <directive module="core" type="section">Directory</directive>
750d12c59545dbbac70390988de94f7e901b08f2niq and <directive module="core" type="section">Location</directive>
750d12c59545dbbac70390988de94f7e901b08f2niq directives. It should be matched with a <code></Files></code>
750d12c59545dbbac70390988de94f7e901b08f2niq directive. The directives given within this section will be applied to
750d12c59545dbbac70390988de94f7e901b08f2niq any object with a basename (last component of filename) matching the
750d12c59545dbbac70390988de94f7e901b08f2niq specified filename. <directive type="section">Files</directive>
750d12c59545dbbac70390988de94f7e901b08f2niq sections are processed in the order they appear in the
750d12c59545dbbac70390988de94f7e901b08f2niq <code>.htaccess</code> files are read, but before <directive
750d12c59545dbbac70390988de94f7e901b08f2niq type="section" module="core">Location</directive> sections. Note
750d12c59545dbbac70390988de94f7e901b08f2niq that <directive type="section">Files</directive> can be nested
750d12c59545dbbac70390988de94f7e901b08f2niq module="core">Directory</directive> sections to restrict the
750d12c59545dbbac70390988de94f7e901b08f2niq portion of the filesystem they apply to.</p>
750d12c59545dbbac70390988de94f7e901b08f2niq <p>The <var>filename</var> argument should include a filename, or
750d12c59545dbbac70390988de94f7e901b08f2niq a wild-card string, where <code>?</code> matches any single character,
80c4526970a11f37c0f8e3b82afdf03902dac3f3slive and <code>*</code> matches any sequences of characters.
80c4526970a11f37c0f8e3b82afdf03902dac3f3slive can also be used, with the addition of the
80c4526970a11f37c0f8e3b82afdf03902dac3f3slive <Files ~ "\.(gif|jpe?g|png)$">
003f0c9fda6664daf5092a0e42f65ede20098153slive <p>would match most common Internet graphics formats. <directive
80c4526970a11f37c0f8e3b82afdf03902dac3f3slive module="core" type="section">FilesMatch</directive> is preferred,
80c4526970a11f37c0f8e3b82afdf03902dac3f3slive however.</p>
a7f40ca49262952d6dd69d021cf5b0c2b452ae4cnd module="core">Directory</directive> and <directive type="section"
a7f40ca49262952d6dd69d021cf5b0c2b452ae4cnd type="section">Files</directive> sections can be used inside
a7f40ca49262952d6dd69d021cf5b0c2b452ae4cnd <code>.htaccess</code> files. This allows users to control access to
80c4526970a11f37c0f8e3b82afdf03902dac3f3slive their own files, at a file-by-file level.</p>
80c4526970a11f37c0f8e3b82afdf03902dac3f3slive<seealso><a href="/sections.html">How <Directory>, <Location>
80c4526970a11f37c0f8e3b82afdf03902dac3f3slive and <Files> sections work</a> for an explanation of how these
a7f40ca49262952d6dd69d021cf5b0c2b452ae4cnd different sections are combined when a request is received</seealso>
80c4526970a11f37c0f8e3b82afdf03902dac3f3slive</directivesynopsis>
80c4526970a11f37c0f8e3b82afdf03902dac3f3slive<description>Contains directives that apply to regular-expression matched
80c4526970a11f37c0f8e3b82afdf03902dac3f3slivefilenames</description>
a7f40ca49262952d6dd69d021cf5b0c2b452ae4cnd<syntax><FilesMatch <var>regex</var>> ... </FilesMatch></syntax>
80c4526970a11f37c0f8e3b82afdf03902dac3f3slive<contextlist><context>server config</context><context>virtual host</context>
80c4526970a11f37c0f8e3b82afdf03902dac3f3slive</contextlist>
6e483e0b8aa3fa574288a7452221392a03e2b9a3noodl <p>The <directive type="section">FilesMatch</directive> directive
80c4526970a11f37c0f8e3b82afdf03902dac3f3slive limits the scope of the enclosed directives by filename, just as the
80c4526970a11f37c0f8e3b82afdf03902dac3f3slive <directive module="core" type="section">Files</directive> directive
80c4526970a11f37c0f8e3b82afdf03902dac3f3slive does. However, it accepts a <glossary ref="regex">regular
a00429a6b3b4dbb113b6dc67cfc0507f610276e9takashi <FilesMatch "\.(gif|jpe?g|png)$">
130d299c4b2b15be45532a176604c71fdc7bea5bnd </example>
130d299c4b2b15be45532a176604c71fdc7bea5bnd <p>would match most common Internet graphics formats.</p>
a00429a6b3b4dbb113b6dc67cfc0507f610276e9takashi<seealso><a href="/sections.html">How <Directory>, <Location>
955d7fc3e7adb6463b7243e15c04e858718e799etakashi and <Files> sections work</a> for an explanation of how these
955d7fc3e7adb6463b7243e15c04e858718e799etakashi different sections are combined when a request is received</seealso>
955d7fc3e7adb6463b7243e15c04e858718e799etakashi</directivesynopsis>
955d7fc3e7adb6463b7243e15c04e858718e799etakashi<directivesynopsis>
955d7fc3e7adb6463b7243e15c04e858718e799etakashi<description>Forces all matching files to be served with the specified
955d7fc3e7adb6463b7243e15c04e858718e799etakashimedia type in the HTTP Content-Type header field</description>
955d7fc3e7adb6463b7243e15c04e858718e799etakashi<syntax>ForceType <var>media-type</var>|None</syntax>
955d7fc3e7adb6463b7243e15c04e858718e799etakashi<contextlist><context>directory</context><context>.htaccess</context>
955d7fc3e7adb6463b7243e15c04e858718e799etakashi</contextlist>
955d7fc3e7adb6463b7243e15c04e858718e799etakashi<compatibility>Moved to the core in Apache httpd 2.0</compatibility>
130d299c4b2b15be45532a176604c71fdc7bea5bnd <directive type="section" module="core">Directory</directive>, or
a7f40ca49262952d6dd69d021cf5b0c2b452ae4cnd <directive type="section" module="core">Location</directive> or
80c4526970a11f37c0f8e3b82afdf03902dac3f3slive <directive type="section" module="core">Files</directive>
80c4526970a11f37c0f8e3b82afdf03902dac3f3slive section, this directive forces all matching files to be served
80c4526970a11f37c0f8e3b82afdf03902dac3f3slive with the content type identification given by
80c4526970a11f37c0f8e3b82afdf03902dac3f3slive <var>media-type</var>. For example, if you had a directory full of
80c4526970a11f37c0f8e3b82afdf03902dac3f3slive GIF files, but did not want to label them all with <code>.gif</code>,
80c4526970a11f37c0f8e3b82afdf03902dac3f3slive you might want to use:</p>
80c4526970a11f37c0f8e3b82afdf03902dac3f3slive <p>Note that this directive overrides other indirect media type
003f0c9fda6664daf5092a0e42f65ede20098153slive associations defined in mime.types or via the
80c4526970a11f37c0f8e3b82afdf03902dac3f3slive <p>You can also override more general
a7f40ca49262952d6dd69d021cf5b0c2b452ae4cnd <Location /images><br />
a7f40ca49262952d6dd69d021cf5b0c2b452ae4cnd </Location><br />
80c4526970a11f37c0f8e3b82afdf03902dac3f3slive # but normal mime-type associations here:<br />
55d36f9b61520c2374ab463e77e8a62daa416398nd ForceType None<br />
80c4526970a11f37c0f8e3b82afdf03902dac3f3slive </Location>
55d36f9b61520c2374ab463e77e8a62daa416398nd <p>This directive primarily overrides the content types generated for
80c4526970a11f37c0f8e3b82afdf03902dac3f3slive static files served out of the filesystem. For resources other than
a7f40ca49262952d6dd69d021cf5b0c2b452ae4cnd static files, where the generator of the response typically specifies
55d36f9b61520c2374ab463e77e8a62daa416398nd a Content-Type, this directive has no effect.</p>
55d36f9b61520c2374ab463e77e8a62daa416398nd</directivesynopsis>
55d36f9b61520c2374ab463e77e8a62daa416398nd<directivesynopsis>
55d36f9b61520c2374ab463e77e8a62daa416398nd<description>Enables DNS lookups on client IP addresses</description>
80c4526970a11f37c0f8e3b82afdf03902dac3f3slive<contextlist><context>server config</context><context>virtual host</context>
bea526116133aa3d7dabd1924bfc580b37fbf22aslive <p>This directive enables DNS lookups so that host names can be
bea526116133aa3d7dabd1924bfc580b37fbf22aslive logged (and passed to CGIs/SSIs in <code>REMOTE_HOST</code>).
fb77c505254b6e9c925e23e734463e87574f8f40kess The value <code>Double</code> refers to doing double-reverse
bea526116133aa3d7dabd1924bfc580b37fbf22aslive DNS lookup. That is, after a reverse lookup is performed, a forward
bea526116133aa3d7dabd1924bfc580b37fbf22aslive lookup is then performed on that result. At least one of the IP
80c4526970a11f37c0f8e3b82afdf03902dac3f3slive addresses in the forward lookup must match the original
80c4526970a11f37c0f8e3b82afdf03902dac3f3slive address. (In "tcpwrappers" terminology this is called
80c4526970a11f37c0f8e3b82afdf03902dac3f3slive <p>Regardless of the setting, when <module>mod_authz_host</module> is
80c4526970a11f37c0f8e3b82afdf03902dac3f3slive used for controlling access by hostname, a double reverse lookup
80c4526970a11f37c0f8e3b82afdf03902dac3f3slive will be performed. This is necessary for security. Note that the
a7f40ca49262952d6dd69d021cf5b0c2b452ae4cnd result of this double-reverse isn't generally available unless you
003f0c9fda6664daf5092a0e42f65ede20098153slive set <code>HostnameLookups Double</code>. For example, if only
003f0c9fda6664daf5092a0e42f65ede20098153slive <code>HostnameLookups On</code> and a request is made to an object
003f0c9fda6664daf5092a0e42f65ede20098153slive that is protected by hostname restrictions, regardless of whether
7b5535ed88e0f561b3bfb3330137bd804846afd4slive the double-reverse fails or not, CGIs will still be passed the
80c4526970a11f37c0f8e3b82afdf03902dac3f3slive single-reverse result in <code>REMOTE_HOST</code>.</p>
80c4526970a11f37c0f8e3b82afdf03902dac3f3slive <p>The default is <code>Off</code> in order to save the network
80c4526970a11f37c0f8e3b82afdf03902dac3f3slive traffic for those sites that don't truly need the reverse
80c4526970a11f37c0f8e3b82afdf03902dac3f3slive lookups done. It is also better for the end users because they
ef8e89e090461194ecadd31e8796a2c51e0531a2kess don't have to suffer the extra latency that a lookup entails.
fb77c505254b6e9c925e23e734463e87574f8f40kess Heavily loaded sites should leave this directive
7b5535ed88e0f561b3bfb3330137bd804846afd4slive <code>Off</code>, since DNS lookups can take considerable
7b5535ed88e0f561b3bfb3330137bd804846afd4slive amounts of time. The utility <program>logresolve</program>, compiled by
7b5535ed88e0f561b3bfb3330137bd804846afd4slive default to the <code>bin</code> subdirectory of your installation
7b5535ed88e0f561b3bfb3330137bd804846afd4slive directory, can be used to look up host names from logged IP addresses
a1ef40892ffa2b44fc249423c5b6c42a74a84c68nd offline.</p>
80c4526970a11f37c0f8e3b82afdf03902dac3f3slive</directivesynopsis>
80c4526970a11f37c0f8e3b82afdf03902dac3f3slive<description>Contains directives that apply only if a condition is
80c4526970a11f37c0f8e3b82afdf03902dac3f3slivesatisfied by a request at runtime</description>
a7f40ca49262952d6dd69d021cf5b0c2b452ae4cnd<syntax><If <var>expression</var>> ... </If></syntax>
7b5535ed88e0f561b3bfb3330137bd804846afd4slive<contextlist><context>server config</context><context>virtual host</context>
7b5535ed88e0f561b3bfb3330137bd804846afd4slive<context>directory</context><context>.htaccess</context>
a7f40ca49262952d6dd69d021cf5b0c2b452ae4cnd</contextlist>
a7f40ca49262952d6dd69d021cf5b0c2b452ae4cnd <p>The <directive type="section">If</directive> directive
a7f40ca49262952d6dd69d021cf5b0c2b452ae4cnd evaluates an expression at runtime, and applies the enclosed
a7f40ca49262952d6dd69d021cf5b0c2b452ae4cnd directives if and only if the expression evaluates to true.
7b5535ed88e0f561b3bfb3330137bd804846afd4slive For example:</p>
80c4526970a11f37c0f8e3b82afdf03902dac3f3slive <If "$req{Host} = ''">
a1ef40892ffa2b44fc249423c5b6c42a74a84c68nd </example>
80c4526970a11f37c0f8e3b82afdf03902dac3f3slive <p>would match HTTP/1.0 requests without a <var>Host:</var> header.</p>
80c4526970a11f37c0f8e3b82afdf03902dac3f3slive <p>You may compare the value of any variable in the request headers
003f0c9fda6664daf5092a0e42f65ede20098153slive ($req), response headers ($resp) or environment ($env) in your
fb77c505254b6e9c925e23e734463e87574f8f40kess expression.</p>
18b4b0fd6056093002ddef488636bf5ebe415ef0erikabele <p>Apart from <code>=</code>, <code>If</code> can use the <code>IN</code>
18b4b0fd6056093002ddef488636bf5ebe415ef0erikabele operator to compare if the expression is in a given range:</p>
80c4526970a11f37c0f8e3b82afdf03902dac3f3slive <If %{REQUEST_METHOD} IN GET,HEAD,OPTIONS>
313bb560bc5c323cfd40c9cad7335b4b8e060aedkess<seealso><a href="/sections.html">How <Directory>, <Location>,
313bb560bc5c323cfd40c9cad7335b4b8e060aedkess <Files> sections work</a> for an explanation of how these
80c4526970a11f37c0f8e3b82afdf03902dac3f3slive different sections are combined when a request is received.
80c4526970a11f37c0f8e3b82afdf03902dac3f3slive <directive type="section">If</directive> has the same precedence
80c4526970a11f37c0f8e3b82afdf03902dac3f3slive and usage as <directive type="section">Files</directive></seealso>
80c4526970a11f37c0f8e3b82afdf03902dac3f3slive</directivesynopsis>
80c4526970a11f37c0f8e3b82afdf03902dac3f3slive<description>Encloses directives that will be processed only
80c4526970a11f37c0f8e3b82afdf03902dac3f3sliveif a test is true at startup</description>
80c4526970a11f37c0f8e3b82afdf03902dac3f3slive<syntax><IfDefine [!]<var>parameter-name</var>> ...
80c4526970a11f37c0f8e3b82afdf03902dac3f3slive </IfDefine></syntax>
80c4526970a11f37c0f8e3b82afdf03902dac3f3slive<contextlist><context>server config</context><context>virtual host</context>
891df99fdfa41fc8a486568f4d31ddf4a571258adreid<context>directory</context><context>.htaccess</context>
891df99fdfa41fc8a486568f4d31ddf4a571258adreid</contextlist>
80c4526970a11f37c0f8e3b82afdf03902dac3f3slive <p>The <code><IfDefine <var>test</var>>...</IfDefine>
80c4526970a11f37c0f8e3b82afdf03902dac3f3slive </code> section is used to mark directives that are conditional. The
80c4526970a11f37c0f8e3b82afdf03902dac3f3slive directives within an <directive type="section">IfDefine</directive>
80c4526970a11f37c0f8e3b82afdf03902dac3f3slive section are only processed if the <var>test</var> is true. If <var>
80c4526970a11f37c0f8e3b82afdf03902dac3f3slive test</var> is false, everything between the start and end markers is
98f5034c8cbf2ef025b317b3e01acae82e143b11trawick ignored.</p>
98f5034c8cbf2ef025b317b3e01acae82e143b11trawick <p>The <var>test</var> in the <directive type="section"
98f5034c8cbf2ef025b317b3e01acae82e143b11trawick >IfDefine</directive> section directive can be one of two forms:</p>
98f5034c8cbf2ef025b317b3e01acae82e143b11trawick <p>In the former case, the directives between the start and end
98f5034c8cbf2ef025b317b3e01acae82e143b11trawick markers are only processed if the parameter named
98f5034c8cbf2ef025b317b3e01acae82e143b11trawick <var>parameter-name</var> is defined. The second format reverses
98f5034c8cbf2ef025b317b3e01acae82e143b11trawick the test, and only processes the directives if
98f5034c8cbf2ef025b317b3e01acae82e143b11trawick <var>parameter-name</var> is <strong>not</strong> defined.</p>
98f5034c8cbf2ef025b317b3e01acae82e143b11trawick <p>The <var>parameter-name</var> argument is a define as given on the
98f5034c8cbf2ef025b317b3e01acae82e143b11trawick <program>httpd</program> command line via <code>-D<var>parameter</var>
c6f90ef0e93c077924fd0c3c0200dba0cb1777c6takashi </code> at the time the server was started or by the <directive
85349f40d98fb3fc7a18ef25dc40eaaae6eead1ctakashi <p><directive type="section">IfDefine</directive> sections are
85349f40d98fb3fc7a18ef25dc40eaaae6eead1ctakashi nest-able, which can be used to implement simple
98f5034c8cbf2ef025b317b3e01acae82e143b11trawick multiple-parameter tests. Example:</p>
80c4526970a11f37c0f8e3b82afdf03902dac3f3slive httpd -DReverseProxy -DUseCache -DMemCache ...<br />
313bb560bc5c323cfd40c9cad7335b4b8e060aedkess <IfDefine ReverseProxy><br />
7245e9b991db85d9d9a587fe5f4051f642ebdc3cchrisd LoadModule proxy_http_module modules/mod_proxy_http.so<br />
80c4526970a11f37c0f8e3b82afdf03902dac3f3slive <IfDefine UseCache><br />
80c4526970a11f37c0f8e3b82afdf03902dac3f3slive <IfDefine MemCache><br />
80c4526970a11f37c0f8e3b82afdf03902dac3f3slive LoadModule mem_cache_module modules/mod_mem_cache.so<br />
80c4526970a11f37c0f8e3b82afdf03902dac3f3slive </IfDefine><br />
130d299c4b2b15be45532a176604c71fdc7bea5bnd <IfDefine !MemCache><br />
80c4526970a11f37c0f8e3b82afdf03902dac3f3slive LoadModule disk_cache_module modules/mod_disk_cache.so<br />
80c4526970a11f37c0f8e3b82afdf03902dac3f3slive </IfDefine>
313bb560bc5c323cfd40c9cad7335b4b8e060aedkess </IfDefine>
313bb560bc5c323cfd40c9cad7335b4b8e060aedkess </IfDefine>
313bb560bc5c323cfd40c9cad7335b4b8e060aedkess </example>
130d299c4b2b15be45532a176604c71fdc7bea5bnd</directivesynopsis>
130d299c4b2b15be45532a176604c71fdc7bea5bnd<description>Encloses directives that are processed conditional on the
130d299c4b2b15be45532a176604c71fdc7bea5bndpresence or absence of a specific module</description>
a7f40ca49262952d6dd69d021cf5b0c2b452ae4cnd<syntax><IfModule [!]<var>module-file</var>|<var>module-identifier</var>> ...
a7f40ca49262952d6dd69d021cf5b0c2b452ae4cnd </IfModule></syntax>
a7f40ca49262952d6dd69d021cf5b0c2b452ae4cnd<contextlist><context>server config</context><context>virtual host</context>
6c5c651b0b97607b8c8b4965c1385c67699f217fnd</contextlist>
a7f40ca49262952d6dd69d021cf5b0c2b452ae4cnd<compatibility>Module identifiers are available in version 2.1 and
a7f40ca49262952d6dd69d021cf5b0c2b452ae4cndlater.</compatibility>
7245e9b991db85d9d9a587fe5f4051f642ebdc3cchrisd <p>The <code><IfModule <var>test</var>>...</IfModule></code>
750d12c59545dbbac70390988de94f7e901b08f2niq section is used to mark directives that are conditional on the presence of
4bb78e7cdd53f50240cff4ad7a97c7ed36483797slive a specific module. The directives within an <directive type="section"
4bb78e7cdd53f50240cff4ad7a97c7ed36483797slive >IfModule</directive> section are only processed if the <var>test</var>
4bb78e7cdd53f50240cff4ad7a97c7ed36483797slive is true. If <var>test</var> is false, everything between the start and
7245e9b991db85d9d9a587fe5f4051f642ebdc3cchrisd end markers is ignored.</p>
4bb78e7cdd53f50240cff4ad7a97c7ed36483797slive <p>The <var>test</var> in the <directive type="section"
4bb78e7cdd53f50240cff4ad7a97c7ed36483797slive >IfModule</directive> section directive can be one of two forms:</p>
7245e9b991db85d9d9a587fe5f4051f642ebdc3cchrisd <p>In the former case, the directives between the start and end
7245e9b991db85d9d9a587fe5f4051f642ebdc3cchrisd markers are only processed if the module named <var>module</var>
7245e9b991db85d9d9a587fe5f4051f642ebdc3cchrisd is included in Apache httpd -- either compiled in or
7245e9b991db85d9d9a587fe5f4051f642ebdc3cchrisd >LoadModule</directive>. The second format reverses the test,
7245e9b991db85d9d9a587fe5f4051f642ebdc3cchrisd and only processes the directives if <var>module</var> is
7245e9b991db85d9d9a587fe5f4051f642ebdc3cchrisd <p>The <var>module</var> argument can be either the module identifier or
7245e9b991db85d9d9a587fe5f4051f642ebdc3cchrisd the file name of the module, at the time it was compiled. For example,
7245e9b991db85d9d9a587fe5f4051f642ebdc3cchrisd <code>mod_rewrite.c</code> is the file name. If a module consists of
7245e9b991db85d9d9a587fe5f4051f642ebdc3cchrisd several source files, use the name of the file containing the string
7245e9b991db85d9d9a587fe5f4051f642ebdc3cchrisd <p><directive type="section">IfModule</directive> sections are
7245e9b991db85d9d9a587fe5f4051f642ebdc3cchrisd nest-able, which can be used to implement simple multiple-module
7245e9b991db85d9d9a587fe5f4051f642ebdc3cchrisd <note>This section should only be used if you need to have one
7245e9b991db85d9d9a587fe5f4051f642ebdc3cchrisd configuration file that works whether or not a specific module
7245e9b991db85d9d9a587fe5f4051f642ebdc3cchrisd is available. In normal operation, directives need not be
7245e9b991db85d9d9a587fe5f4051f642ebdc3cchrisd placed in <directive type="section">IfModule</directive>
7245e9b991db85d9d9a587fe5f4051f642ebdc3cchrisd sections.</note>
7245e9b991db85d9d9a587fe5f4051f642ebdc3cchrisd</directivesynopsis>
80c4526970a11f37c0f8e3b82afdf03902dac3f3slive<directivesynopsis>
80c4526970a11f37c0f8e3b82afdf03902dac3f3slive<description>Includes other configuration files from within
80c4526970a11f37c0f8e3b82afdf03902dac3f3slivethe server configuration files</description>
80c4526970a11f37c0f8e3b82afdf03902dac3f3slive<syntax>Include [<var>optional</var>|<var>strict</var>] <var>file-path</var>|<var>directory-path</var>|<var>wildcard</var></syntax>
313bb560bc5c323cfd40c9cad7335b4b8e060aedkess<contextlist><context>server config</context><context>virtual host</context>
80c4526970a11f37c0f8e3b82afdf03902dac3f3slive</contextlist>
7245e9b991db85d9d9a587fe5f4051f642ebdc3cchrisd<compatibility>Wildcard matching available in 2.0.41 and later, directory
80c4526970a11f37c0f8e3b82afdf03902dac3f3slivewildcard matching available in 2.3.6 and later</compatibility>
80c4526970a11f37c0f8e3b82afdf03902dac3f3slive <p>This directive allows inclusion of other configuration files
80c4526970a11f37c0f8e3b82afdf03902dac3f3slive from within the server configuration files.</p>
d3f27ec18dfa6283e852aa98253212edafaa0e2brbowen <p>Shell-style (<code>fnmatch()</code>) wildcard characters can be used
313bb560bc5c323cfd40c9cad7335b4b8e060aedkess in the filename or directory parts of the path to include several files
d3f27ec18dfa6283e852aa98253212edafaa0e2brbowen at once, in alphabetical order. In addition, if
80c4526970a11f37c0f8e3b82afdf03902dac3f3slive <directive>Include</directive> points to a directory, rather than a file,
80c4526970a11f37c0f8e3b82afdf03902dac3f3slive Apache httpd will read all files in that directory and any subdirectory.
80c4526970a11f37c0f8e3b82afdf03902dac3f3slive However, including entire directories is not recommended, because it is
80c4526970a11f37c0f8e3b82afdf03902dac3f3slive easy to accidentally leave temporary files in a directory that can cause
d3f27ec18dfa6283e852aa98253212edafaa0e2brbowen <program>httpd</program> to fail. Instead, we encourage you to use the
d3f27ec18dfa6283e852aa98253212edafaa0e2brbowen wildcard syntax shown below, to include files that match a particular
d3f27ec18dfa6283e852aa98253212edafaa0e2brbowen pattern, such as *.conf, for example.</p>
130d299c4b2b15be45532a176604c71fdc7bea5bnd <p>When a wildcard is specified for a <strong>file</strong> component of
130d299c4b2b15be45532a176604c71fdc7bea5bnd the path, and no file matches the wildcard, the
130d299c4b2b15be45532a176604c71fdc7bea5bnd directive will be <strong>silently ignored</strong>. When a wildcard is
7ef9b6763ad87846cf83c3f71467f43e349d080aerikabele specified for a <strong>directory</strong> component of the path, and
d3f27ec18dfa6283e852aa98253212edafaa0e2brbowen no directory matches the wildcard, the
d3f27ec18dfa6283e852aa98253212edafaa0e2brbowen <directive module="core">Include</directive> directive will
80c4526970a11f37c0f8e3b82afdf03902dac3f3slive <strong>fail with an error</strong> saying the directory cannot be found.
03e0a375c2435102fb2b51e34cccff52acbfddcdnd <p>For further control over the behaviour of the server when no files or
03e0a375c2435102fb2b51e34cccff52acbfddcdnd directories match, prefix the path with the modifiers <var>optional</var>
03e0a375c2435102fb2b51e34cccff52acbfddcdnd or <var>strict</var>. If <var>optional</var> is specified, any wildcard
03e0a375c2435102fb2b51e34cccff52acbfddcdnd file or directory that does not match will be silently ignored. If
03e0a375c2435102fb2b51e34cccff52acbfddcdnd <var>strict</var> is specified, any wildcard file or directory that does
03e0a375c2435102fb2b51e34cccff52acbfddcdnd not match at least one file will cause server startup to fail.</p>
03e0a375c2435102fb2b51e34cccff52acbfddcdnd <p>When a directory or file component of the path is
a51fafd9c1463954daf49f94e76d078c1eb5c9bdnd specified exactly, and that directory or file does not exist,
03e0a375c2435102fb2b51e34cccff52acbfddcdnd <directive module="core">Include</directive> directive will fail with an
03e0a375c2435102fb2b51e34cccff52acbfddcdnd error saying the file or directory cannot be found.</p>
03e0a375c2435102fb2b51e34cccff52acbfddcdnd <p>The file path specified may be an absolute path, or may be relative
03e0a375c2435102fb2b51e34cccff52acbfddcdnd to the <directive module="core">ServerRoot</directive> directory.</p>
03e0a375c2435102fb2b51e34cccff52acbfddcdnd </example>
03e0a375c2435102fb2b51e34cccff52acbfddcdnd </example>
03e0a375c2435102fb2b51e34cccff52acbfddcdnd <p>Wildcards may be included in the directory or file portion of the
03e0a375c2435102fb2b51e34cccff52acbfddcdnd path. In the following example, the server will fail to load if no
03e0a375c2435102fb2b51e34cccff52acbfddcdnd directories match conf/vhosts/*, but will load successfully if no
03e0a375c2435102fb2b51e34cccff52acbfddcdnd files match *.conf.</p>
80c4526970a11f37c0f8e3b82afdf03902dac3f3slive <p>In this example, the server will fail to load if either
80c4526970a11f37c0f8e3b82afdf03902dac3f3slive conf/vhosts/* matches no directories, or if *.conf matches no files:</p>
a7f40ca49262952d6dd69d021cf5b0c2b452ae4cnd <p>In this example, the server load successfully if either conf/vhosts/*
80c4526970a11f37c0f8e3b82afdf03902dac3f3slive matches no directories, or if *.conf matches no files:</p>
80c4526970a11f37c0f8e3b82afdf03902dac3f3slive</directivesynopsis>
313bb560bc5c323cfd40c9cad7335b4b8e060aedkess<directivesynopsis>
fb77c505254b6e9c925e23e734463e87574f8f40kess<description>Enables HTTP persistent connections</description>
80c4526970a11f37c0f8e3b82afdf03902dac3f3slive<contextlist><context>server config</context><context>virtual host</context>
80c4526970a11f37c0f8e3b82afdf03902dac3f3slive</contextlist>
d3f27ec18dfa6283e852aa98253212edafaa0e2brbowen <p>The Keep-Alive extension to HTTP/1.0 and the persistent
d3f27ec18dfa6283e852aa98253212edafaa0e2brbowen connection feature of HTTP/1.1 provide long-lived HTTP sessions
313bb560bc5c323cfd40c9cad7335b4b8e060aedkess which allow multiple requests to be sent over the same TCP
d3f27ec18dfa6283e852aa98253212edafaa0e2brbowen connection. In some cases this has been shown to result in an
d3f27ec18dfa6283e852aa98253212edafaa0e2brbowen almost 50% speedup in latency times for HTML documents with
d3f27ec18dfa6283e852aa98253212edafaa0e2brbowen many images. To enable Keep-Alive connections, set
d3f27ec18dfa6283e852aa98253212edafaa0e2brbowen <p>For HTTP/1.0 clients, Keep-Alive connections will only be
80c4526970a11f37c0f8e3b82afdf03902dac3f3slive used if they are specifically requested by a client. In
80c4526970a11f37c0f8e3b82afdf03902dac3f3slive addition, a Keep-Alive connection with an HTTP/1.0 client can
80c4526970a11f37c0f8e3b82afdf03902dac3f3slive only be used when the length of the content is known in
80c4526970a11f37c0f8e3b82afdf03902dac3f3slive advance. This implies that dynamic content such as CGI output,
80c4526970a11f37c0f8e3b82afdf03902dac3f3slive SSI pages, and server-generated directory listings will
313bb560bc5c323cfd40c9cad7335b4b8e060aedkess generally not use Keep-Alive connections to HTTP/1.0 clients.
80c4526970a11f37c0f8e3b82afdf03902dac3f3slive For HTTP/1.1 clients, persistent connections are the default
a7f40ca49262952d6dd69d021cf5b0c2b452ae4cnd unless otherwise specified. If the client requests it, chunked
80c4526970a11f37c0f8e3b82afdf03902dac3f3slive encoding will be used in order to send content of unknown
80c4526970a11f37c0f8e3b82afdf03902dac3f3slive length over persistent connections.</p>
80c4526970a11f37c0f8e3b82afdf03902dac3f3slive <p>When a client uses a Keep-Alive connection it will be counted
a7f40ca49262952d6dd69d021cf5b0c2b452ae4cnd as a single "request" for the <directive module="mpm_common"
80c4526970a11f37c0f8e3b82afdf03902dac3f3slive >MaxConnectionsPerChild</directive> directive, regardless
80c4526970a11f37c0f8e3b82afdf03902dac3f3slive of how many requests are sent using the connection.</p>
80c4526970a11f37c0f8e3b82afdf03902dac3f3slive<seealso><directive module="core">MaxKeepAliveRequests</directive></seealso>
80c4526970a11f37c0f8e3b82afdf03902dac3f3slive</directivesynopsis>
80c4526970a11f37c0f8e3b82afdf03902dac3f3slive<directivesynopsis>
80c4526970a11f37c0f8e3b82afdf03902dac3f3slive<description>Amount of time the server will wait for subsequent
80c4526970a11f37c0f8e3b82afdf03902dac3f3sliverequests on a persistent connection</description>
80c4526970a11f37c0f8e3b82afdf03902dac3f3slive<contextlist><context>server config</context><context>virtual host</context>
80c4526970a11f37c0f8e3b82afdf03902dac3f3slive</contextlist>
80c4526970a11f37c0f8e3b82afdf03902dac3f3slive<compatibility>Specifying a value in milliseconds is available in
80c4526970a11f37c0f8e3b82afdf03902dac3f3sliveApache httpd 2.3.2 and later</compatibility>
80c4526970a11f37c0f8e3b82afdf03902dac3f3slive <p>The number of seconds Apache httpd will wait for a subsequent
80c4526970a11f37c0f8e3b82afdf03902dac3f3slive request before closing the connection. By adding a postfix of ms the
d3f27ec18dfa6283e852aa98253212edafaa0e2brbowen timeout can be also set in milliseconds. Once a request has been
d3f27ec18dfa6283e852aa98253212edafaa0e2brbowen received, the timeout value specified by the
d3f27ec18dfa6283e852aa98253212edafaa0e2brbowen <directive module="core">Timeout</directive> directive applies.</p>
a7f40ca49262952d6dd69d021cf5b0c2b452ae4cnd <p>Setting <directive>KeepAliveTimeout</directive> to a high value
d3f27ec18dfa6283e852aa98253212edafaa0e2brbowen may cause performance problems in heavily loaded servers. The
d3f27ec18dfa6283e852aa98253212edafaa0e2brbowen higher the timeout, the more server processes will be kept
80c4526970a11f37c0f8e3b82afdf03902dac3f3slive occupied waiting on connections with idle clients.</p>
80c4526970a11f37c0f8e3b82afdf03902dac3f3slive <p>In a name-based virtual host context, the value of the first
80c4526970a11f37c0f8e3b82afdf03902dac3f3slive defined virtual host (the default host) in a set of <directive
80c4526970a11f37c0f8e3b82afdf03902dac3f3slive module="core">NameVirtualHost</directive> will be used.
80c4526970a11f37c0f8e3b82afdf03902dac3f3slive The other values will be ignored.</p>
ae134ecc8faf4e6a8eb68e1c3724506771442a46rbowen</directivesynopsis>
80c4526970a11f37c0f8e3b82afdf03902dac3f3slive<description>Restrict enclosed access controls to only certain HTTP
72580dbc2a55511f13f377063725b9f143b20826stoddardmethods</description>
72580dbc2a55511f13f377063725b9f143b20826stoddard<syntax><Limit <var>method</var> [<var>method</var>] ... > ...
80c4526970a11f37c0f8e3b82afdf03902dac3f3slive </Limit></syntax>
313bb560bc5c323cfd40c9cad7335b4b8e060aedkess<contextlist><context>directory</context><context>.htaccess</context>
72580dbc2a55511f13f377063725b9f143b20826stoddard</contextlist>
72580dbc2a55511f13f377063725b9f143b20826stoddard <p>Access controls are normally effective for
72580dbc2a55511f13f377063725b9f143b20826stoddard <strong>all</strong> access methods, and this is the usual
56d7eed7205462540aec7202cd82d9f5516fc537kess desired behavior. <strong>In the general case, access control
72580dbc2a55511f13f377063725b9f143b20826stoddard directives should not be placed within a
80c4526970a11f37c0f8e3b82afdf03902dac3f3slive <directive type="section">Limit</directive> section.</strong></p>
80c4526970a11f37c0f8e3b82afdf03902dac3f3slive <p>The purpose of the <directive type="section">Limit</directive>
d3f27ec18dfa6283e852aa98253212edafaa0e2brbowen directive is to restrict the effect of the access controls to the
d3f27ec18dfa6283e852aa98253212edafaa0e2brbowen nominated HTTP methods. For all other methods, the access
d3f27ec18dfa6283e852aa98253212edafaa0e2brbowen restrictions that are enclosed in the <directive
d3f27ec18dfa6283e852aa98253212edafaa0e2brbowen type="section">Limit</directive> bracket <strong>will have no
d3f27ec18dfa6283e852aa98253212edafaa0e2brbowen effect</strong>. The following example applies the access control
ef8e89e090461194ecadd31e8796a2c51e0531a2kess only to the methods <code>POST</code>, <code>PUT</code>, and
d3f27ec18dfa6283e852aa98253212edafaa0e2brbowen <code>DELETE</code>, leaving all other methods unprotected:</p>
d3f27ec18dfa6283e852aa98253212edafaa0e2brbowen <Limit POST PUT DELETE><br />
80c4526970a11f37c0f8e3b82afdf03902dac3f3slive Require valid-user<br />
80c4526970a11f37c0f8e3b82afdf03902dac3f3slive </Limit>
80c4526970a11f37c0f8e3b82afdf03902dac3f3slive <p>The method names listed can be one or more of: <code>GET</code>,
80c4526970a11f37c0f8e3b82afdf03902dac3f3slive <code>POST</code>, <code>PUT</code>, <code>DELETE</code>,
80c4526970a11f37c0f8e3b82afdf03902dac3f3slive <code>PATCH</code>, <code>PROPFIND</code>, <code>PROPPATCH</code>,
80c4526970a11f37c0f8e3b82afdf03902dac3f3slive <code>MKCOL</code>, <code>COPY</code>, <code>MOVE</code>,
80c4526970a11f37c0f8e3b82afdf03902dac3f3slive <code>LOCK</code>, and <code>UNLOCK</code>. <strong>The method name is
80c4526970a11f37c0f8e3b82afdf03902dac3f3slive case-sensitive.</strong> If <code>GET</code> is used it will also
72580dbc2a55511f13f377063725b9f143b20826stoddard restrict <code>HEAD</code> requests. The <code>TRACE</code> method
72580dbc2a55511f13f377063725b9f143b20826stoddard module="core">LimitExcept</directive> section should always be
80c4526970a11f37c0f8e3b82afdf03902dac3f3slive used in preference to a <directive type="section">Limit</directive>
80c4526970a11f37c0f8e3b82afdf03902dac3f3slive section when restricting access, since a <directive type="section"
80c4526970a11f37c0f8e3b82afdf03902dac3f3slive module="core">LimitExcept</directive> section provides protection
80c4526970a11f37c0f8e3b82afdf03902dac3f3slive against arbitrary methods.</note>
80c4526970a11f37c0f8e3b82afdf03902dac3f3slive <directive type="section" module="core">LimitExcept</directive>
80c4526970a11f37c0f8e3b82afdf03902dac3f3slive directives may be nested. In this case, each successive level of
80c4526970a11f37c0f8e3b82afdf03902dac3f3slive <directive type="section">Limit</directive> or <directive
d3f27ec18dfa6283e852aa98253212edafaa0e2brbowen type="section" module="core">LimitExcept</directive> directives must
d3f27ec18dfa6283e852aa98253212edafaa0e2brbowen further restrict the set of methods to which access controls apply.</p>
ef8e89e090461194ecadd31e8796a2c51e0531a2kess <directive type="section">LimitExcept</directive> directives with
d3f27ec18dfa6283e852aa98253212edafaa0e2brbowen the <directive module="mod_authz_core">Require</directive> directive,
d3f27ec18dfa6283e852aa98253212edafaa0e2brbowen note that the first <directive module="mod_authz_core">Require</directive>
d3f27ec18dfa6283e852aa98253212edafaa0e2brbowen to succeed authorizes the request, regardless of the presence of other
d3f27ec18dfa6283e852aa98253212edafaa0e2brbowen <directive module="mod_authz_core">Require</directive> directives.</note>
80c4526970a11f37c0f8e3b82afdf03902dac3f3slive <p>For example, given the following configuration, all users will
80c4526970a11f37c0f8e3b82afdf03902dac3f3slive <code>Require group editors</code> directive will be ignored
80c4526970a11f37c0f8e3b82afdf03902dac3f3slive in all cases:</p>
80c4526970a11f37c0f8e3b82afdf03902dac3f3slive <LimitExcept GET>
18b4b0fd6056093002ddef488636bf5ebe415ef0erikabele Require valid-user
80c4526970a11f37c0f8e3b82afdf03902dac3f3slive </LimitExcept><br />
80c4526970a11f37c0f8e3b82afdf03902dac3f3slive <Limit POST>
80c4526970a11f37c0f8e3b82afdf03902dac3f3slive Require group editors
d3f27ec18dfa6283e852aa98253212edafaa0e2brbowen </Limit>
a7f40ca49262952d6dd69d021cf5b0c2b452ae4cnd</directivesynopsis>
80c4526970a11f37c0f8e3b82afdf03902dac3f3slive<description>Restrict access controls to all HTTP methods
80c4526970a11f37c0f8e3b82afdf03902dac3f3sliveexcept the named ones</description>
80c4526970a11f37c0f8e3b82afdf03902dac3f3slive<syntax><LimitExcept <var>method</var> [<var>method</var>] ... > ...
80c4526970a11f37c0f8e3b82afdf03902dac3f3slive </LimitExcept></syntax>
80c4526970a11f37c0f8e3b82afdf03902dac3f3slive<contextlist><context>directory</context><context>.htaccess</context>
80c4526970a11f37c0f8e3b82afdf03902dac3f3slive</contextlist>
80c4526970a11f37c0f8e3b82afdf03902dac3f3slive <p><directive type="section">LimitExcept</directive> and
80c4526970a11f37c0f8e3b82afdf03902dac3f3slive a group of access control directives which will then apply to any
80c4526970a11f37c0f8e3b82afdf03902dac3f3slive HTTP access method <strong>not</strong> listed in the arguments;
6b64034fa2a644ba291c484c0c01c7df5b8d982ckess i.e., it is the opposite of a <directive type="section"
80c4526970a11f37c0f8e3b82afdf03902dac3f3slive module="core">Limit</directive> section and can be used to control
80c4526970a11f37c0f8e3b82afdf03902dac3f3slive both standard and nonstandard/unrecognized methods. See the
80c4526970a11f37c0f8e3b82afdf03902dac3f3slive type="section">Limit</directive> for more details.</p>
80c4526970a11f37c0f8e3b82afdf03902dac3f3slive <LimitExcept POST GET><br />
234c8b28171d7e12b3c1f85b60fabd7c908a9c37slive Require valid-user<br />
234c8b28171d7e12b3c1f85b60fabd7c908a9c37slive </LimitExcept>
234c8b28171d7e12b3c1f85b60fabd7c908a9c37slive</directivesynopsis>
234c8b28171d7e12b3c1f85b60fabd7c908a9c37slive<directivesynopsis>
234c8b28171d7e12b3c1f85b60fabd7c908a9c37slive<description>Determine maximum number of internal redirects and nested
234c8b28171d7e12b3c1f85b60fabd7c908a9c37slivesubrequests</description>
234c8b28171d7e12b3c1f85b60fabd7c908a9c37slive<syntax>LimitInternalRecursion <var>number</var> [<var>number</var>]</syntax>
234c8b28171d7e12b3c1f85b60fabd7c908a9c37slive<contextlist><context>server config</context><context>virtual host</context>
234c8b28171d7e12b3c1f85b60fabd7c908a9c37slive</contextlist>
234c8b28171d7e12b3c1f85b60fabd7c908a9c37slive<compatibility>Available in Apache httpd 2.0.47 and later</compatibility>
beb923bec9bff2b49ce5027df2fe944e2b74e28brederpj <p>An internal redirect happens, for example, when using the <directive
beb923bec9bff2b49ce5027df2fe944e2b74e28brederpj module="mod_actions">Action</directive> directive, which internally
dc223428958ad9ff05011545bcdda000887b93e5slive redirects the original request to a CGI script. A subrequest is Apache httpd's
80c4526970a11f37c0f8e3b82afdf03902dac3f3slive mechanism to find out what would happen for some URI if it were requested.
80c4526970a11f37c0f8e3b82afdf03902dac3f3slive For example, <module>mod_dir</module> uses subrequests to look for the
80c4526970a11f37c0f8e3b82afdf03902dac3f3slive files listed in the <directive module="mod_dir">DirectoryIndex</directive>
313bb560bc5c323cfd40c9cad7335b4b8e060aedkess directive.</p>
d8c44cd75cf575fe51319280c12445109e878523noodl <p><directive>LimitInternalRecursion</directive> prevents the server
80c4526970a11f37c0f8e3b82afdf03902dac3f3slive from crashing when entering an infinite loop of internal redirects or
030108b1816bcda3d925df65357feabdce83bc94slive subrequests. Such loops are usually caused by misconfigurations.</p>
80c4526970a11f37c0f8e3b82afdf03902dac3f3slive <p>The directive stores two different limits, which are evaluated on
a7f40ca49262952d6dd69d021cf5b0c2b452ae4cnd per-request basis. The first <var>number</var> is the maximum number of
a7f40ca49262952d6dd69d021cf5b0c2b452ae4cnd internal redirects, that may follow each other. The second <var>number</var>
a7f40ca49262952d6dd69d021cf5b0c2b452ae4cnd determines, how deep subrequests may be nested. If you specify only one
a7f40ca49262952d6dd69d021cf5b0c2b452ae4cnd <var>number</var>, it will be assigned to both limits.</p>
313bb560bc5c323cfd40c9cad7335b4b8e060aedkess LimitInternalRecursion 5
313bb560bc5c323cfd40c9cad7335b4b8e060aedkess </example>
313bb560bc5c323cfd40c9cad7335b4b8e060aedkess</directivesynopsis>
80c4526970a11f37c0f8e3b82afdf03902dac3f3slive<directivesynopsis>
80c4526970a11f37c0f8e3b82afdf03902dac3f3slive<description>Restricts the total size of the HTTP request body sent
80c4526970a11f37c0f8e3b82afdf03902dac3f3slivefrom the client</description>
130d299c4b2b15be45532a176604c71fdc7bea5bnd<contextlist><context>server config</context><context>virtual host</context>
130d299c4b2b15be45532a176604c71fdc7bea5bnd</contextlist>
e8811b6d38f756b325446ded5d96857d13856511takashi <p>This directive specifies the number of <var>bytes</var> from 0
130d299c4b2b15be45532a176604c71fdc7bea5bnd (meaning unlimited) to 2147483647 (2GB) that are allowed in a
130d299c4b2b15be45532a176604c71fdc7bea5bnd request body.</p>
a7f40ca49262952d6dd69d021cf5b0c2b452ae4cnd <p>The <directive>LimitRequestBody</directive> directive allows
a7f40ca49262952d6dd69d021cf5b0c2b452ae4cnd the user to set a limit on the allowed size of an HTTP request
a7f40ca49262952d6dd69d021cf5b0c2b452ae4cnd message body within the context in which the directive is given
a7f40ca49262952d6dd69d021cf5b0c2b452ae4cnd (server, per-directory, per-file or per-location). If the client
a7f40ca49262952d6dd69d021cf5b0c2b452ae4cnd request exceeds that limit, the server will return an error
05201775eaa6b363b8a119c8aea5db246b967591yoshiki response instead of servicing the request. The size of a normal
a7f40ca49262952d6dd69d021cf5b0c2b452ae4cnd request message body will vary greatly depending on the nature of
a7f40ca49262952d6dd69d021cf5b0c2b452ae4cnd the resource and the methods allowed on that resource. CGI scripts
a7f40ca49262952d6dd69d021cf5b0c2b452ae4cnd typically use the message body for retrieving form information.
a7f40ca49262952d6dd69d021cf5b0c2b452ae4cnd Implementations of the <code>PUT</code> method will require
a7f40ca49262952d6dd69d021cf5b0c2b452ae4cnd a value at least as large as any representation that the server
313bb560bc5c323cfd40c9cad7335b4b8e060aedkess wishes to accept for that resource.</p>
a7f40ca49262952d6dd69d021cf5b0c2b452ae4cnd <p>This directive gives the server administrator greater
a7f40ca49262952d6dd69d021cf5b0c2b452ae4cnd control over abnormal client request behavior, which may be
a7f40ca49262952d6dd69d021cf5b0c2b452ae4cnd useful for avoiding some forms of denial-of-service
a7f40ca49262952d6dd69d021cf5b0c2b452ae4cnd attacks.</p>
a7f40ca49262952d6dd69d021cf5b0c2b452ae4cnd <p>If, for example, you are permitting file upload to a particular
a7f40ca49262952d6dd69d021cf5b0c2b452ae4cnd location, and wish to limit the size of the uploaded file to 100K,
a7f40ca49262952d6dd69d021cf5b0c2b452ae4cnd you might use the following directive:</p>
313bb560bc5c323cfd40c9cad7335b4b8e060aedkess LimitRequestBody 102400
313bb560bc5c323cfd40c9cad7335b4b8e060aedkess </example>
80c4526970a11f37c0f8e3b82afdf03902dac3f3slive</directivesynopsis>
80c4526970a11f37c0f8e3b82afdf03902dac3f3slive<directivesynopsis>
80c4526970a11f37c0f8e3b82afdf03902dac3f3slive<description>Limits the number of HTTP request header fields that
80c4526970a11f37c0f8e3b82afdf03902dac3f3slivewill be accepted from the client</description>
8490b2f9f6469d5089163f6dd303d9a81f8e908ctrawick<syntax>LimitRequestFields <var>number</var></syntax>
80c4526970a11f37c0f8e3b82afdf03902dac3f3slive<contextlist><context>server config</context><context>virtual host</context></contextlist>
80c4526970a11f37c0f8e3b82afdf03902dac3f3slive <p><var>Number</var> is an integer from 0 (meaning unlimited) to
6b64034fa2a644ba291c484c0c01c7df5b8d982ckess 32767. The default value is defined by the compile-time
6b64034fa2a644ba291c484c0c01c7df5b8d982ckess constant <code>DEFAULT_LIMIT_REQUEST_FIELDS</code> (100 as
030108b1816bcda3d925df65357feabdce83bc94slive distributed).</p>
80c4526970a11f37c0f8e3b82afdf03902dac3f3slive <p>The <directive>LimitRequestFields</directive> directive allows
a7f40ca49262952d6dd69d021cf5b0c2b452ae4cnd the server administrator to modify the limit on the number of
a7f40ca49262952d6dd69d021cf5b0c2b452ae4cnd request header fields allowed in an HTTP request. A server needs
a7f40ca49262952d6dd69d021cf5b0c2b452ae4cnd this value to be larger than the number of fields that a normal
a7f40ca49262952d6dd69d021cf5b0c2b452ae4cnd client request might include. The number of request header fields
a7f40ca49262952d6dd69d021cf5b0c2b452ae4cnd used by a client rarely exceeds 20, but this may vary among
a7f40ca49262952d6dd69d021cf5b0c2b452ae4cnd different client implementations, often depending upon the extent
80c4526970a11f37c0f8e3b82afdf03902dac3f3slive to which a user has configured their browser to support detailed
80c4526970a11f37c0f8e3b82afdf03902dac3f3slive content negotiation. Optional HTTP extensions are often expressed
313bb560bc5c323cfd40c9cad7335b4b8e060aedkess using request header fields.</p>
313bb560bc5c323cfd40c9cad7335b4b8e060aedkess <p>This directive gives the server administrator greater
80c4526970a11f37c0f8e3b82afdf03902dac3f3slive control over abnormal client request behavior, which may be
80c4526970a11f37c0f8e3b82afdf03902dac3f3slive useful for avoiding some forms of denial-of-service attacks.
80c4526970a11f37c0f8e3b82afdf03902dac3f3slive The value should be increased if normal clients see an error
80c4526970a11f37c0f8e3b82afdf03902dac3f3slive response from the server that indicates too many fields were
80c4526970a11f37c0f8e3b82afdf03902dac3f3slive sent in the request.</p>
80c4526970a11f37c0f8e3b82afdf03902dac3f3slive LimitRequestFields 50
80c4526970a11f37c0f8e3b82afdf03902dac3f3slive <p> When name-based virtual hosting is used, the value for this
a7f40ca49262952d6dd69d021cf5b0c2b452ae4cnd directive is taken from the default (first-listed) virtual host for the
80c4526970a11f37c0f8e3b82afdf03902dac3f3slive <directive>NameVirtualHost</directive> the connection was mapped to.</p>
1597043cec6ad37fa4154bf09b0fccdabed1a239slive</directivesynopsis>
530eba85dbd41b8a0fa5255d3648d1440199a661slive<directivesynopsis>
530eba85dbd41b8a0fa5255d3648d1440199a661slive<description>Limits the size of the HTTP request header allowed from the
80c4526970a11f37c0f8e3b82afdf03902dac3f3sliveclient</description>
530eba85dbd41b8a0fa5255d3648d1440199a661slive<syntax>LimitRequestFieldSize <var>bytes</var></syntax>
80c4526970a11f37c0f8e3b82afdf03902dac3f3slive<contextlist><context>server config</context><context>virtual host</context></contextlist>
80c4526970a11f37c0f8e3b82afdf03902dac3f3slive <p>This directive specifies the number of <var>bytes</var>
80c4526970a11f37c0f8e3b82afdf03902dac3f3slive that will be allowed in an HTTP request header.</p>
80c4526970a11f37c0f8e3b82afdf03902dac3f3slive <p>The <directive>LimitRequestFieldSize</directive> directive
80c4526970a11f37c0f8e3b82afdf03902dac3f3slive allows the server administrator to reduce or increase the limit
80c4526970a11f37c0f8e3b82afdf03902dac3f3slive on the allowed size of an HTTP request header field. A server
80c4526970a11f37c0f8e3b82afdf03902dac3f3slive needs this value to be large enough to hold any one header field
80c4526970a11f37c0f8e3b82afdf03902dac3f3slive from a normal client request. The size of a normal request header
80c4526970a11f37c0f8e3b82afdf03902dac3f3slive field will vary greatly among different client implementations,
80c4526970a11f37c0f8e3b82afdf03902dac3f3slive often depending upon the extent to which a user has configured
80c4526970a11f37c0f8e3b82afdf03902dac3f3slive their browser to support detailed content negotiation. SPNEGO
80c4526970a11f37c0f8e3b82afdf03902dac3f3slive authentication headers can be up to 12392 bytes.</p>
80c4526970a11f37c0f8e3b82afdf03902dac3f3slive <p>This directive gives the server administrator greater
80c4526970a11f37c0f8e3b82afdf03902dac3f3slive control over abnormal client request behavior, which may be
80c4526970a11f37c0f8e3b82afdf03902dac3f3slive useful for avoiding some forms of denial-of-service attacks.</p>
80c4526970a11f37c0f8e3b82afdf03902dac3f3slive LimitRequestFieldSize 4094
80c4526970a11f37c0f8e3b82afdf03902dac3f3slive <note>Under normal conditions, the value should not be changed from
80c4526970a11f37c0f8e3b82afdf03902dac3f3slive the default.</note>
80c4526970a11f37c0f8e3b82afdf03902dac3f3slive <p> When name-based virtual hosting is used, the value for this
80c4526970a11f37c0f8e3b82afdf03902dac3f3slive directive is taken from the default (first-listed) virtual host for the
80c4526970a11f37c0f8e3b82afdf03902dac3f3slive <directive>NameVirtualHost</directive> the connection was mapped to.</p>
80c4526970a11f37c0f8e3b82afdf03902dac3f3slive</directivesynopsis>
80c4526970a11f37c0f8e3b82afdf03902dac3f3slive<directivesynopsis>
80c4526970a11f37c0f8e3b82afdf03902dac3f3slive<description>Limit the size of the HTTP request line that will be accepted
80c4526970a11f37c0f8e3b82afdf03902dac3f3slivefrom the client</description>
80c4526970a11f37c0f8e3b82afdf03902dac3f3slive<contextlist><context>server config</context><context>virtual host</context></contextlist>
80c4526970a11f37c0f8e3b82afdf03902dac3f3slive <p>This directive sets the number of <var>bytes</var> that will be
80c4526970a11f37c0f8e3b82afdf03902dac3f3slive allowed on the HTTP request-line.</p>
80c4526970a11f37c0f8e3b82afdf03902dac3f3slive <p>The <directive>LimitRequestLine</directive> directive allows
80c4526970a11f37c0f8e3b82afdf03902dac3f3slive the server administrator to reduce or increase the limit on the allowed size
80c4526970a11f37c0f8e3b82afdf03902dac3f3slive of a client's HTTP request-line. Since the request-line consists of the
80c4526970a11f37c0f8e3b82afdf03902dac3f3slive HTTP method, URI, and protocol version, the
80c4526970a11f37c0f8e3b82afdf03902dac3f3slive <directive>LimitRequestLine</directive> directive places a
80c4526970a11f37c0f8e3b82afdf03902dac3f3slive restriction on the length of a request-URI allowed for a request
80c4526970a11f37c0f8e3b82afdf03902dac3f3slive on the server. A server needs this value to be large enough to
80c4526970a11f37c0f8e3b82afdf03902dac3f3slive hold any of its resource names, including any information that
80c4526970a11f37c0f8e3b82afdf03902dac3f3slive might be passed in the query part of a <code>GET</code> request.</p>
80c4526970a11f37c0f8e3b82afdf03902dac3f3slive <p>This directive gives the server administrator greater
80c4526970a11f37c0f8e3b82afdf03902dac3f3slive control over abnormal client request behavior, which may be
80c4526970a11f37c0f8e3b82afdf03902dac3f3slive useful for avoiding some forms of denial-of-service attacks.</p>
80c4526970a11f37c0f8e3b82afdf03902dac3f3slive LimitRequestLine 4094
80c4526970a11f37c0f8e3b82afdf03902dac3f3slive <note>Under normal conditions, the value should not be changed from
80c4526970a11f37c0f8e3b82afdf03902dac3f3slive the default.</note>
80c4526970a11f37c0f8e3b82afdf03902dac3f3slive <p> When name-based virtual hosting is used, the value for this
80c4526970a11f37c0f8e3b82afdf03902dac3f3slive directive is taken from the default (first-listed) virtual host for the
80c4526970a11f37c0f8e3b82afdf03902dac3f3slive <directive>NameVirtualHost</directive> the connection was mapped to.</p>
a7f40ca49262952d6dd69d021cf5b0c2b452ae4cnd</directivesynopsis>
a7f40ca49262952d6dd69d021cf5b0c2b452ae4cnd<directivesynopsis>
8b052d682204371decc64f942aede5ef1da98955erikabele<description>Limits the size of an XML-based request body</description>
8b052d682204371decc64f942aede5ef1da98955erikabele<syntax>LimitXMLRequestBody <var>bytes</var></syntax>
8b052d682204371decc64f942aede5ef1da98955erikabele<contextlist><context>server config</context><context>virtual host</context>
8b052d682204371decc64f942aede5ef1da98955erikabele<context>directory</context><context>.htaccess</context></contextlist>
80c4526970a11f37c0f8e3b82afdf03902dac3f3slive <p>Limit (in bytes) on maximum size of an XML-based request
80c4526970a11f37c0f8e3b82afdf03902dac3f3slive body. A value of <code>0</code> will disable any checking.</p>
80c4526970a11f37c0f8e3b82afdf03902dac3f3slive LimitXMLRequestBody 0
80c4526970a11f37c0f8e3b82afdf03902dac3f3slive</directivesynopsis>
fb77c505254b6e9c925e23e734463e87574f8f40kess<description>Applies the enclosed directives only to matching
80c4526970a11f37c0f8e3b82afdf03902dac3f3sliveURLs</description>
80c4526970a11f37c0f8e3b82afdf03902dac3f3slive<syntax><Location
d3f27ec18dfa6283e852aa98253212edafaa0e2brbowen <var>URL-path</var>|<var>URL</var>> ... </Location></syntax>
d3f27ec18dfa6283e852aa98253212edafaa0e2brbowen<contextlist><context>server config</context><context>virtual host</context>
d3f27ec18dfa6283e852aa98253212edafaa0e2brbowen</contextlist>
a7f40ca49262952d6dd69d021cf5b0c2b452ae4cnd <p>The <directive type="section">Location</directive> directive
80c4526970a11f37c0f8e3b82afdf03902dac3f3slive limits the scope of the enclosed directives by URL. It is similar to the
80c4526970a11f37c0f8e3b82afdf03902dac3f3slive <directive type="section" module="core">Directory</directive>
80c4526970a11f37c0f8e3b82afdf03902dac3f3slive directive, and starts a subsection which is terminated with a
80c4526970a11f37c0f8e3b82afdf03902dac3f3slive type="section">Location</directive> sections are processed in the
003f0c9fda6664daf5092a0e42f65ede20098153slive order they appear in the configuration file, after the <directive
80c4526970a11f37c0f8e3b82afdf03902dac3f3slive type="section" module="core">Directory</directive> sections and
a7f40ca49262952d6dd69d021cf5b0c2b452ae4cnd <code>.htaccess</code> files are read, and after the <directive
80c4526970a11f37c0f8e3b82afdf03902dac3f3slive type="section" module="core">Files</directive> sections.</p>
80c4526970a11f37c0f8e3b82afdf03902dac3f3slive <p><directive type="section">Location</directive> sections operate
80c4526970a11f37c0f8e3b82afdf03902dac3f3slive completely outside the filesystem. This has several consequences.
80c4526970a11f37c0f8e3b82afdf03902dac3f3slive Most importantly, <directive type="section">Location</directive>
80c4526970a11f37c0f8e3b82afdf03902dac3f3slive directives should not be used to control access to filesystem
80c4526970a11f37c0f8e3b82afdf03902dac3f3slive locations. Since several different URLs may map to the same
a7f40ca49262952d6dd69d021cf5b0c2b452ae4cnd filesystem location, such access controls may by circumvented.</p>
a7f40ca49262952d6dd69d021cf5b0c2b452ae4cnd <p>Use <directive type="section">Location</directive> to apply
80c4526970a11f37c0f8e3b82afdf03902dac3f3slive directives to content that lives outside the filesystem. For
80c4526970a11f37c0f8e3b82afdf03902dac3f3slive content that lives in the filesystem, use <directive
80c4526970a11f37c0f8e3b82afdf03902dac3f3slive type="section" module="core">Directory</directive> and <directive
80c4526970a11f37c0f8e3b82afdf03902dac3f3slive type="section" module="core">Files</directive>. An exception is
80c4526970a11f37c0f8e3b82afdf03902dac3f3slive <code><Location /></code>, which is an easy way to
80c4526970a11f37c0f8e3b82afdf03902dac3f3slive apply a configuration to the entire server.</p>
80c4526970a11f37c0f8e3b82afdf03902dac3f3slive <p>For all origin (non-proxy) requests, the URL to be matched is a
80c4526970a11f37c0f8e3b82afdf03902dac3f3slive URL-path of the form <code>/path/</code>. <em>No scheme, hostname,
80c4526970a11f37c0f8e3b82afdf03902dac3f3slive port, or query string may be included.</em> For proxy requests, the
313bb560bc5c323cfd40c9cad7335b4b8e060aedkess URL to be matched is of the form
313bb560bc5c323cfd40c9cad7335b4b8e060aedkess <code>scheme://servername/path</code>, and you must include the
313bb560bc5c323cfd40c9cad7335b4b8e060aedkess prefix.</p>
313bb560bc5c323cfd40c9cad7335b4b8e060aedkess <p>The URL may use wildcards. In a wild-card string, <code>?</code> matches
313bb560bc5c323cfd40c9cad7335b4b8e060aedkess any single character, and <code>*</code> matches any sequences of
313bb560bc5c323cfd40c9cad7335b4b8e060aedkess characters. Neither wildcard character matches a / in the URL-path.</p>
80c4526970a11f37c0f8e3b82afdf03902dac3f3slive <p><glossary ref="regex">Regular expressions</glossary>
80c4526970a11f37c0f8e3b82afdf03902dac3f3slive can also be used, with the addition of the <code>~</code>
a7f40ca49262952d6dd69d021cf5b0c2b452ae4cnd character. For example:</p>
a7f40ca49262952d6dd69d021cf5b0c2b452ae4cnd <Location ~ "/(extra|special)/data">
a7f40ca49262952d6dd69d021cf5b0c2b452ae4cnd </example>
a7f40ca49262952d6dd69d021cf5b0c2b452ae4cnd <p>would match URLs that contained the substring <code>/extra/data</code>
fb77c505254b6e9c925e23e734463e87574f8f40kess type="section" module="core">LocationMatch</directive> behaves
a7f40ca49262952d6dd69d021cf5b0c2b452ae4cnd identical to the regex version of <directive
cf02129aebf73dd0bdf369b172eb481ff76ac5f6colm type="section">Location</directive>, and is preferred, for the
a7f40ca49262952d6dd69d021cf5b0c2b452ae4cnd simple reason that <code>~</code> is hard to distinguish from
52bb691f8e13e9d0b55fcc214018ee85846fa87frbowen functionality is especially useful when combined with the
a7f40ca49262952d6dd69d021cf5b0c2b452ae4cnd directive. For example, to enable status requests, but allow them
a7f40ca49262952d6dd69d021cf5b0c2b452ae4cnd only from browsers at <code>example.com</code>, you might use:</p>
fb77c505254b6e9c925e23e734463e87574f8f40kess <Location /status><br />
27303c8bb552a8a5fc859feb735d686fc59f59a1yoshiki SetHandler server-status<br />
a7f40ca49262952d6dd69d021cf5b0c2b452ae4cnd Order Deny,Allow<br />
a7f40ca49262952d6dd69d021cf5b0c2b452ae4cnd Deny from all<br />
a7f40ca49262952d6dd69d021cf5b0c2b452ae4cnd </Location>
a7f40ca49262952d6dd69d021cf5b0c2b452ae4cnd </example>
a7f40ca49262952d6dd69d021cf5b0c2b452ae4cnd <p>The slash character has special meaning depending on where in a
a7f40ca49262952d6dd69d021cf5b0c2b452ae4cnd URL it appears. People may be used to its behavior in the filesystem
3386d67e54f92fdf6a3ffc5f7f8081eed6c44badslive where multiple adjacent slashes are frequently collapsed to a single
3386d67e54f92fdf6a3ffc5f7f8081eed6c44badslive slash (<em>i.e.</em>, <code>/home///foo</code> is the same as
05201775eaa6b363b8a119c8aea5db246b967591yoshiki <code>/home/foo</code>). In URL-space this is not necessarily true.
d3f27ec18dfa6283e852aa98253212edafaa0e2brbowen The <directive type="section" module="core">LocationMatch</directive>
d3f27ec18dfa6283e852aa98253212edafaa0e2brbowen directive and the regex version of <directive type="section"
80c4526970a11f37c0f8e3b82afdf03902dac3f3slive >Location</directive> require you to explicitly specify multiple
80c4526970a11f37c0f8e3b82afdf03902dac3f3slive slashes if that is your intention.</p>
80c4526970a11f37c0f8e3b82afdf03902dac3f3slive <p>For example, <code><LocationMatch ^/abc></code> would match
80c4526970a11f37c0f8e3b82afdf03902dac3f3slive the request URL <code>/abc</code> but not the request URL <code>
80c4526970a11f37c0f8e3b82afdf03902dac3f3slive //abc</code>. The (non-regex) <directive type="section"
80c4526970a11f37c0f8e3b82afdf03902dac3f3slive >Location</directive> directive behaves similarly when used for
a7f40ca49262952d6dd69d021cf5b0c2b452ae4cnd proxy requests. But when (non-regex) <directive type="section"
80c4526970a11f37c0f8e3b82afdf03902dac3f3slive >Location</directive> is used for non-proxy requests it will
80c4526970a11f37c0f8e3b82afdf03902dac3f3slive implicitly match multiple slashes with a single slash. For example,
80c4526970a11f37c0f8e3b82afdf03902dac3f3slive if you specify <code><Location /abc/def></code> and the
80c4526970a11f37c0f8e3b82afdf03902dac3f3slive request is to <code>/abc//def</code> then it will match.</p>
80c4526970a11f37c0f8e3b82afdf03902dac3f3slive<seealso><a href="/sections.html">How <Directory>, <Location>
80c4526970a11f37c0f8e3b82afdf03902dac3f3slive and <Files> sections work</a> for an explanation of how these
80c4526970a11f37c0f8e3b82afdf03902dac3f3slive different sections are combined when a request is received.</seealso>
80c4526970a11f37c0f8e3b82afdf03902dac3f3slive<seealso><directive module="core">LocationMatch</directive></seealso>
a7f40ca49262952d6dd69d021cf5b0c2b452ae4cnd</directivesynopsis>
80c4526970a11f37c0f8e3b82afdf03902dac3f3slive<description>Applies the enclosed directives only to regular-expression
313bb560bc5c323cfd40c9cad7335b4b8e060aedkessmatching URLs</description>
80c4526970a11f37c0f8e3b82afdf03902dac3f3slive<syntax><LocationMatch
fb77c505254b6e9c925e23e734463e87574f8f40kess <var>regex</var>> ... </LocationMatch></syntax>
80c4526970a11f37c0f8e3b82afdf03902dac3f3slive<contextlist><context>server config</context><context>virtual host</context>
80c4526970a11f37c0f8e3b82afdf03902dac3f3slive</contextlist>
80c4526970a11f37c0f8e3b82afdf03902dac3f3slive <p>The <directive type="section">LocationMatch</directive> directive
13e5182a0c199ecc7a73db97b6448a544e940868slive limits the scope of the enclosed directives by URL, in an identical manner
13e5182a0c199ecc7a73db97b6448a544e940868slive to <directive module="core" type="section">Location</directive>. However,
80c4526970a11f37c0f8e3b82afdf03902dac3f3slive it takes a <glossary ref="regex">regular expression</glossary>
313bb560bc5c323cfd40c9cad7335b4b8e060aedkess as an argument instead of a simple string. For example:</p>
80c4526970a11f37c0f8e3b82afdf03902dac3f3slive <LocationMatch "/(extra|special)/data">
a7f40ca49262952d6dd69d021cf5b0c2b452ae4cnd </example>
a7f40ca49262952d6dd69d021cf5b0c2b452ae4cnd <p>would match URLs that contained the substring <code>/extra/data</code>
a7f40ca49262952d6dd69d021cf5b0c2b452ae4cnd<seealso><a href="/sections.html">How <Directory>, <Location>
a7f40ca49262952d6dd69d021cf5b0c2b452ae4cnd and <Files> sections work</a> for an explanation of how these
1c5fe3e61f0f3202ae0f853740d53f3aff4c4afbslive different sections are combined when a request is received</seealso>
1c5fe3e61f0f3202ae0f853740d53f3aff4c4afbslive</directivesynopsis>
a7f40ca49262952d6dd69d021cf5b0c2b452ae4cnd<directivesynopsis>
313bb560bc5c323cfd40c9cad7335b4b8e060aedkess<description>Controls the verbosity of the ErrorLog</description>
80c4526970a11f37c0f8e3b82afdf03902dac3f3slive<contextlist><context>server config</context><context>virtual host</context>
80c4526970a11f37c0f8e3b82afdf03902dac3f3slive</contextlist>
80c4526970a11f37c0f8e3b82afdf03902dac3f3slive<compatibility>Per-module and per-directory configuration is available in
80c4526970a11f37c0f8e3b82afdf03902dac3f3slive Apache HTTP Server 2.3.6 and later</compatibility>
13e5182a0c199ecc7a73db97b6448a544e940868slive <p><directive>LogLevel</directive> adjusts the verbosity of the
b00583f8e126bbb00b06dcf06af06c9d07978701kess messages recorded in the error logs (see <directive
13e5182a0c199ecc7a73db97b6448a544e940868slive module="core">ErrorLog</directive> directive). The following
80c4526970a11f37c0f8e3b82afdf03902dac3f3slive <var>level</var>s are available, in order of decreasing
313bb560bc5c323cfd40c9cad7335b4b8e060aedkess significance:</p>
0d5b778ac63bc803c0dd1a4fdef371fe7a0f4b57kess <columnspec><column width=".2"/><column width=".3"/><column width=".5"/>
13e5182a0c199ecc7a73db97b6448a544e940868slive </columnspec>
1c5fe3e61f0f3202ae0f853740d53f3aff4c4afbslive <td>"getpwuid: couldn't determine user name from uid"</td>
13e5182a0c199ecc7a73db97b6448a544e940868slive <td>"socket: Failed to get a socket, exiting child"</td>
80c4526970a11f37c0f8e3b82afdf03902dac3f3slive <td>"child process 1234 did not exit, sending another
130d299c4b2b15be45532a176604c71fdc7bea5bnd SIGHUP"</td>
130d299c4b2b15be45532a176604c71fdc7bea5bnd <td>"httpd: caught SIGBUS, attempting to dump core in
fb77c505254b6e9c925e23e734463e87574f8f40kess <td>"Server seems busy, (you may need to increase
313bb560bc5c323cfd40c9cad7335b4b8e060aedkess <td>"proxy: CONNECT: sending the CONNECT request to the remote proxy"</td>
530eba85dbd41b8a0fa5255d3648d1440199a661slive <td>"read from buffered SSL brigade, mode 0, 17 bytes"</td>
80c4526970a11f37c0f8e3b82afdf03902dac3f3slive <td>"map lookup FAILED: map=rewritemap key=keyname"</td>
80c4526970a11f37c0f8e3b82afdf03902dac3f3slive <td>"cache lookup FAILED, forcing new map lookup"</td>
80c4526970a11f37c0f8e3b82afdf03902dac3f3slive <td>Trace messages, dumping large amounts of data</td>
80c4526970a11f37c0f8e3b82afdf03902dac3f3slive <td>"| 0000: 02 23 44 30 13 40 ac 34 df 3d bf 9a 19 49 39 15 |"</td>
80c4526970a11f37c0f8e3b82afdf03902dac3f3slive <td>Trace messages, dumping large amounts of data</td>
80c4526970a11f37c0f8e3b82afdf03902dac3f3slive <td>"| 0000: 02 23 44 30 13 40 ac 34 df 3d bf 9a 19 49 39 15 |"</td>
80c4526970a11f37c0f8e3b82afdf03902dac3f3slive <p>When a particular level is specified, messages from all
80c4526970a11f37c0f8e3b82afdf03902dac3f3slive other levels of higher significance will be reported as well.
18b4b0fd6056093002ddef488636bf5ebe415ef0erikabele <em>E.g.</em>, when <code>LogLevel info</code> is specified,
18b4b0fd6056093002ddef488636bf5ebe415ef0erikabele then messages with log levels of <code>notice</code> and
80c4526970a11f37c0f8e3b82afdf03902dac3f3slive recommended.</p>
ef8e89e090461194ecadd31e8796a2c51e0531a2kess LogLevel notice
80c4526970a11f37c0f8e3b82afdf03902dac3f3slive <p>When logging to a regular file messages of the level
80c4526970a11f37c0f8e3b82afdf03902dac3f3slive <code>notice</code> cannot be suppressed and thus are always
80c4526970a11f37c0f8e3b82afdf03902dac3f3slive logged. However, this doesn't apply when logging is done
80c4526970a11f37c0f8e3b82afdf03902dac3f3slive <p>Specifying a level without a module name will reset the level
80c4526970a11f37c0f8e3b82afdf03902dac3f3slive for all modules to that level. Specifying a level with a module
80c4526970a11f37c0f8e3b82afdf03902dac3f3slive name will set the level for that module only. It is possible to
80c4526970a11f37c0f8e3b82afdf03902dac3f3slive use the module source file name, the module identifier, or the
80c4526970a11f37c0f8e3b82afdf03902dac3f3slive module identifier with the trailing <code>_module</code> omitted
80c4526970a11f37c0f8e3b82afdf03902dac3f3slive as module specification. This means the following three specifications
80c4526970a11f37c0f8e3b82afdf03902dac3f3slive are equivalent:</p>
80c4526970a11f37c0f8e3b82afdf03902dac3f3slive LogLevel info ssl:warn<br />
80c4526970a11f37c0f8e3b82afdf03902dac3f3slive LogLevel info ssl_module:warn<br />
18b4b0fd6056093002ddef488636bf5ebe415ef0erikabele <p>It is also possible to change the level per directory:</p>
80c4526970a11f37c0f8e3b82afdf03902dac3f3slive LogLevel info<br />
80c4526970a11f37c0f8e3b82afdf03902dac3f3slive LogLevel debug<br />
80c4526970a11f37c0f8e3b82afdf03902dac3f3slive </Files>
80c4526970a11f37c0f8e3b82afdf03902dac3f3slive Per directory loglevel configuration only affects messages that are
80c4526970a11f37c0f8e3b82afdf03902dac3f3slive logged after the request has been parsed and that are associated with
80c4526970a11f37c0f8e3b82afdf03902dac3f3slive the request. Log messages which are associated with the connection or
80c4526970a11f37c0f8e3b82afdf03902dac3f3slive the server are not affected.
80c4526970a11f37c0f8e3b82afdf03902dac3f3slive</directivesynopsis>
80c4526970a11f37c0f8e3b82afdf03902dac3f3slive<directivesynopsis>
313bb560bc5c323cfd40c9cad7335b4b8e060aedkess<description>Number of requests allowed on a persistent
313bb560bc5c323cfd40c9cad7335b4b8e060aedkessconnection</description>
9b5e2c5e769dc678a1aca06df75c32022b2f1492trawick<syntax>MaxKeepAliveRequests <var>number</var></syntax>
313bb560bc5c323cfd40c9cad7335b4b8e060aedkess<contextlist><context>server config</context><context>virtual host</context>
313bb560bc5c323cfd40c9cad7335b4b8e060aedkess</contextlist>
80c4526970a11f37c0f8e3b82afdf03902dac3f3slive <p>The <directive>MaxKeepAliveRequests</directive> directive
80c4526970a11f37c0f8e3b82afdf03902dac3f3slive limits the number of requests allowed per connection when
80c4526970a11f37c0f8e3b82afdf03902dac3f3slive <directive module="core" >KeepAlive</directive> is on. If it is
80c4526970a11f37c0f8e3b82afdf03902dac3f3slive set to <code>0</code>, unlimited requests will be allowed. We
80c4526970a11f37c0f8e3b82afdf03902dac3f3slive recommend that this setting be kept to a high value for maximum
80c4526970a11f37c0f8e3b82afdf03902dac3f3slive server performance.</p>
fb77c505254b6e9c925e23e734463e87574f8f40kess MaxKeepAliveRequests 500
003f0c9fda6664daf5092a0e42f65ede20098153slive</directivesynopsis>
ef8e89e090461194ecadd31e8796a2c51e0531a2kess<directivesynopsis>
80c4526970a11f37c0f8e3b82afdf03902dac3f3slive<description>Configures mutex mechanism and lock file directory for all
80c4526970a11f37c0f8e3b82afdf03902dac3f3sliveor specified mutexes</description>
80c4526970a11f37c0f8e3b82afdf03902dac3f3slive<syntax>Mutex <var>mechanism</var> [default|<var>mutex-name</var>] ... [OmitPID]</syntax>
4cafc94e99922f00654e1779d30c2cccf5278c4fkess<contextlist><context>server config</context></contextlist>
4cafc94e99922f00654e1779d30c2cccf5278c4fkess<compatibility>Available in Apache HTTP Server 2.3.4 and later</compatibility>
4cafc94e99922f00654e1779d30c2cccf5278c4fkess <p>The <directive>Mutex</directive> directive sets the mechanism,
4cafc94e99922f00654e1779d30c2cccf5278c4fkess and optionally the lock file location, that httpd and modules use
4cafc94e99922f00654e1779d30c2cccf5278c4fkess to serialize access to resources. Specify <code>default</code> as
4cafc94e99922f00654e1779d30c2cccf5278c4fkess the first argument to change the settings for all mutexes; specify
27303c8bb552a8a5fc859feb735d686fc59f59a1yoshiki a mutex name (see table below) as the first argument to override
4cafc94e99922f00654e1779d30c2cccf5278c4fkess defaults only for that mutex.</p>
4cafc94e99922f00654e1779d30c2cccf5278c4fkess <p>The <directive>Mutex</directive> directive is typically used in
4cafc94e99922f00654e1779d30c2cccf5278c4fkess the following exceptional situations:</p>
4cafc94e99922f00654e1779d30c2cccf5278c4fkess <li>change the mutex mechanism when the default mechanism selected
4cafc94e99922f00654e1779d30c2cccf5278c4fkess by <glossary>APR</glossary> has a functional or performance
4cafc94e99922f00654e1779d30c2cccf5278c4fkess problem</li>
96a8ac87abbb04c2a925f7fde5eb12bf1d1f4bc3slive <li>change the directory used by file-based mutexes when the
96a8ac87abbb04c2a925f7fde5eb12bf1d1f4bc3slive default directory does not support locking</li>
96a8ac87abbb04c2a925f7fde5eb12bf1d1f4bc3slive <p>This directive only configures mutexes which have been registered
96a8ac87abbb04c2a925f7fde5eb12bf1d1f4bc3slive with the core server using the <code>ap_mutex_register()</code> API.
96a8ac87abbb04c2a925f7fde5eb12bf1d1f4bc3slive All modules bundled with httpd support the <directive>Mutex</directive>
96a8ac87abbb04c2a925f7fde5eb12bf1d1f4bc3slive directive, but third-party modules may not. Consult the documentation
96a8ac87abbb04c2a925f7fde5eb12bf1d1f4bc3slive of the third-party module, which must indicate the mutex name(s) which
96a8ac87abbb04c2a925f7fde5eb12bf1d1f4bc3slive can be configured if this directive is supported.</p>
96a8ac87abbb04c2a925f7fde5eb12bf1d1f4bc3slive <p>The following mutex <em>mechanisms</em> are available:</p>
96a8ac87abbb04c2a925f7fde5eb12bf1d1f4bc3slive <p>This selects the default locking implementation, as determined by
4cafc94e99922f00654e1779d30c2cccf5278c4fkess <glossary>APR</glossary>. The default locking implementation can
fb77c505254b6e9c925e23e734463e87574f8f40kess be displayed by running <program>httpd</program> with the
96a8ac87abbb04c2a925f7fde5eb12bf1d1f4bc3slive <p>This effectively disables the mutex, and is only allowed for a
96a8ac87abbb04c2a925f7fde5eb12bf1d1f4bc3slive mutex if the module indicates that it is a valid choice. Consult the
80c4526970a11f37c0f8e3b82afdf03902dac3f3slive <p>This is a mutex variant based on a Posix semaphore.</p>
003f0c9fda6664daf5092a0e42f65ede20098153slive <p>The semaphore ownership is not recovered if a thread in the process
80c4526970a11f37c0f8e3b82afdf03902dac3f3slive holding the mutex segfaults, resulting in a hang of the web server.</p>
80c4526970a11f37c0f8e3b82afdf03902dac3f3slive <p>This is a mutex variant based on a SystemV IPC semaphore.</p>
733738e83a9b0113476e3f67992c2278d61ee4dakess <p>It is possible to "leak" SysV semaphores if processes crash
733738e83a9b0113476e3f67992c2278d61ee4dakess before the semaphore is removed.</p>
2e5e2673cb64d3e4d445d911c6f61ac171020725nd <p>The semaphore API allows for a denial of service attack by any
2e5e2673cb64d3e4d445d911c6f61ac171020725nd CGIs running under the same uid as the webserver (<em>i.e.</em>,
2e5e2673cb64d3e4d445d911c6f61ac171020725nd all CGIs, unless you use something like <program>suexec</program>
a7f40ca49262952d6dd69d021cf5b0c2b452ae4cnd <p>This selects the "best" available semaphore implementation, choosing
80c4526970a11f37c0f8e3b82afdf03902dac3f3slive between Posix and SystemV IPC semaphores, in that order.</p></li>
80c4526970a11f37c0f8e3b82afdf03902dac3f3slive <p>This is a mutex variant based on cross-process Posix thread
80c4526970a11f37c0f8e3b82afdf03902dac3f3slive mutexes.</p>
003f0c9fda6664daf5092a0e42f65ede20098153slive <p>On most systems, if a child process terminates abnormally while
80c4526970a11f37c0f8e3b82afdf03902dac3f3slive holding a mutex that uses this implementation, the server will deadlock
a7f40ca49262952d6dd69d021cf5b0c2b452ae4cnd and stop responding to requests. When this occurs, the server will
80c4526970a11f37c0f8e3b82afdf03902dac3f3slive require a manual restart to recover.</p>
80c4526970a11f37c0f8e3b82afdf03902dac3f3slive <p>Solaris is a notable exception as it provides a mechanism which
80c4526970a11f37c0f8e3b82afdf03902dac3f3slive usually allows the mutex to be recovered after a child process
80c4526970a11f37c0f8e3b82afdf03902dac3f3slive terminates abnormally while holding a mutex.</p>
80c4526970a11f37c0f8e3b82afdf03902dac3f3slive <p>If your system implements the
206b5dce9e48924aa9f12ce87f14856a4cd3fb68takashi <code>pthread_mutexattr_setrobust_np()</code> function, you may be able
a7f40ca49262952d6dd69d021cf5b0c2b452ae4cnd <p>This is a mutex variant where a physical (lock-)file and the
80c4526970a11f37c0f8e3b82afdf03902dac3f3slive <p>When multiple mutexes based on this mechanism are used within
80c4526970a11f37c0f8e3b82afdf03902dac3f3slive multi-threaded, multi-process environments, deadlock errors (EDEADLK)
80c4526970a11f37c0f8e3b82afdf03902dac3f3slive can be reported for valid mutex operations if <code>fcntl()</code>
80c4526970a11f37c0f8e3b82afdf03902dac3f3slive is not thread-aware, such as on Solaris.</p>
e08ad1a326852610a7930269638a43657fc50d06sctemme <p>This is similar to the <code>fcntl:/path/to/mutex</code> method
80c4526970a11f37c0f8e3b82afdf03902dac3f3slive with the exception that the <code>flock()</code> function is used to
80c4526970a11f37c0f8e3b82afdf03902dac3f3slive <p>This selects the "best" available file locking implementation,
80c4526970a11f37c0f8e3b82afdf03902dac3f3slive choosing between <code>fcntl</code> and <code>flock</code>, in that
80c4526970a11f37c0f8e3b82afdf03902dac3f3slive <p>Most mechanisms are only available on selected platforms, where the
fb77c505254b6e9c925e23e734463e87574f8f40kess underlying platform and <glossary>APR</glossary> support it. Mechanisms
9b5e2c5e769dc678a1aca06df75c32022b2f1492trawick which aren't available on all platforms are <em>posixsem</em>,
80c4526970a11f37c0f8e3b82afdf03902dac3f3slive <em>sysvsem</em>, <em>sem</em>, <em>pthread</em>, <em>fcntl</em>,
80c4526970a11f37c0f8e3b82afdf03902dac3f3slive <p>With the file-based mechanisms <em>fcntl</em> and <em>flock</em>,
a7f40ca49262952d6dd69d021cf5b0c2b452ae4cnd the path, if provided, is a directory where the lock file will be created.
a7f40ca49262952d6dd69d021cf5b0c2b452ae4cnd The default directory is httpd's run-time file directory relative to
a7f40ca49262952d6dd69d021cf5b0c2b452ae4cnd <directive module="core">ServerRoot</directive>. Always use a local disk
80c4526970a11f37c0f8e3b82afdf03902dac3f3slive filesystem for <code>/path/to/mutex</code> and never a directory residing
80c4526970a11f37c0f8e3b82afdf03902dac3f3slive on a NFS- or AFS-filesystem. The basename of the file will be the mutex
80c4526970a11f37c0f8e3b82afdf03902dac3f3slive type, an optional instance string provided by the module, and unless the
fb77c505254b6e9c925e23e734463e87574f8f40kess <code>OmitPID</code> keyword is specified, the process id of the httpd
e08ad1a326852610a7930269638a43657fc50d06sctemme parent process will be appended to to make the file name unique, avoiding
e08ad1a326852610a7930269638a43657fc50d06sctemme conflicts when multiple httpd instances share a lock file directory. For
e08ad1a326852610a7930269638a43657fc50d06sctemme example, if the mutex name is <code>mpm-accept</code> and the lock file
e08ad1a326852610a7930269638a43657fc50d06sctemme directory is <code>/var/httpd/locks</code>, the lock file name for the
80c4526970a11f37c0f8e3b82afdf03902dac3f3slive httpd instance with parent process id 12345 would be
80c4526970a11f37c0f8e3b82afdf03902dac3f3slive <p>It is best to <em>avoid</em> putting mutex files in a world-writable
80c4526970a11f37c0f8e3b82afdf03902dac3f3slive directory such as <code>/var/tmp</code> because someone could create
80c4526970a11f37c0f8e3b82afdf03902dac3f3slive a denial of service attack and prevent the server from starting by
80c4526970a11f37c0f8e3b82afdf03902dac3f3slive creating a lockfile with the same name as the one the server will try
e08ad1a326852610a7930269638a43657fc50d06sctemme to create.</p>
e08ad1a326852610a7930269638a43657fc50d06sctemme <p>The following table documents the names of mutexes used by httpd
e08ad1a326852610a7930269638a43657fc50d06sctemme and bundled modules.</p>
80c4526970a11f37c0f8e3b82afdf03902dac3f3slive <td><module>prefork</module> and <module>worker</module> MPMs</td>
80c4526970a11f37c0f8e3b82afdf03902dac3f3slive <td>incoming connections, to avoid the thundering herd problem;
80c4526970a11f37c0f8e3b82afdf03902dac3f3slive for more information, refer to the
e08ad1a326852610a7930269638a43657fc50d06sctemme <a href="/misc/perf-tuning.html">performance tuning</a>
80c4526970a11f37c0f8e3b82afdf03902dac3f3slive documentation</td>
80c4526970a11f37c0f8e3b82afdf03902dac3f3slive <td>communication with external mapping programs, to avoid
80c4526970a11f37c0f8e3b82afdf03902dac3f3slive intermixed I/O from multiple requests</td>
80c4526970a11f37c0f8e3b82afdf03902dac3f3slive <td>callback function of a particular client module</td>
fcc04773f0f2cc73650485facef9cd77f2d5bd65nd <p>The <code>OmitPID</code> keyword suppresses the addition of the httpd
7228d3b2eebddc214348190bcc62d80b5e7087e2rbowen parent process id from the lock file name.</p>
58e56a1d61ae176cc5ecb7c4863881736947d8b8rbowen <p>In the following example, the mutex mechanism for the MPM accept
a7f40ca49262952d6dd69d021cf5b0c2b452ae4cnd mutex will be changed from the compiled-in default to <code>fcntl</code>,
58e56a1d61ae176cc5ecb7c4863881736947d8b8rbowen with the associated lock file created in directory
58e56a1d61ae176cc5ecb7c4863881736947d8b8rbowen <code>/var/httpd/locks</code>. The mutex mechanism for all other mutexes
80c4526970a11f37c0f8e3b82afdf03902dac3f3slive will be changed from the compiled-in default to <code>sysvsem</code>.</p>
80c4526970a11f37c0f8e3b82afdf03902dac3f3slive Mutex default sysvsem<br />
ef8e89e090461194ecadd31e8796a2c51e0531a2kess </example>
80c4526970a11f37c0f8e3b82afdf03902dac3f3slive</directivesynopsis>
80c4526970a11f37c0f8e3b82afdf03902dac3f3slive<directivesynopsis>
80c4526970a11f37c0f8e3b82afdf03902dac3f3slive<description>Designates an IP address for name-virtual
80c4526970a11f37c0f8e3b82afdf03902dac3f3slivehosting</description>
80c4526970a11f37c0f8e3b82afdf03902dac3f3slive<syntax>NameVirtualHost <var>addr</var>[:<var>port</var>]</syntax>
80c4526970a11f37c0f8e3b82afdf03902dac3f3slive<contextlist><context>server config</context></contextlist>
80c4526970a11f37c0f8e3b82afdf03902dac3f3slive<p>A single <directive>NameVirtualHost</directive> directive
80c4526970a11f37c0f8e3b82afdf03902dac3f3sliveidentifies a set of identical virtual hosts on which the server will
80c4526970a11f37c0f8e3b82afdf03902dac3f3slivefurther select from on the basis of the <em>hostname</em>
fb77c505254b6e9c925e23e734463e87574f8f40kessrequested by the client. The <directive>NameVirtualHost</directive>
fb77c505254b6e9c925e23e734463e87574f8f40kessdirective is a required directive if you want to configure
ef8e89e090461194ecadd31e8796a2c51e0531a2kess<p>This directive, and the corresponding <directive >VirtualHost</directive>,
ef8e89e090461194ecadd31e8796a2c51e0531a2kess<em>must</em> be qualified with a port number if the server supports both HTTP
ef8e89e090461194ecadd31e8796a2c51e0531a2kessand HTTPS connections.</p>
80c4526970a11f37c0f8e3b82afdf03902dac3f3slive<p>Although <var>addr</var> can be a hostname, it is recommended
530eba85dbd41b8a0fa5255d3648d1440199a661slivethat you always use an IP address or a wildcard. A wildcard
80c4526970a11f37c0f8e3b82afdf03902dac3f3sliveNameVirtualHost matches only virtualhosts that also have a literal wildcard
80c4526970a11f37c0f8e3b82afdf03902dac3f3sliveas their argument.</p>
80c4526970a11f37c0f8e3b82afdf03902dac3f3slive<p>In cases where a firewall or other proxy receives the requests and
80c4526970a11f37c0f8e3b82afdf03902dac3f3sliveforwards them on a different IP address to the server, you must specify the
80c4526970a11f37c0f8e3b82afdf03902dac3f3sliveIP address of the physical interface on the machine which will be
23b36269d124e7a6aaa5221891f7ae2ef3eeb158jerenkrantzservicing the requests. </p>
7b5535ed88e0f561b3bfb3330137bd804846afd4slive<p> In the example below, requests received on interface 192.0.2.1 and port 80
7b5535ed88e0f561b3bfb3330137bd804846afd4slivewill only select among the first two virtual hosts. Requests received on
80c4526970a11f37c0f8e3b82afdf03902dac3f3sliveport 80 on any other interface will only select among the third and fourth
f35c904c3b359610a46e94fbb4ba8495b2338521slivevirtual hosts. In the common case where the interface isn't important
80c4526970a11f37c0f8e3b82afdf03902dac3f3sliveto the mapping, only the "*:80" NameVirtualHost and VirtualHost directives
80c4526970a11f37c0f8e3b82afdf03902dac3f3sliveare necessary.</p>
ef8e89e090461194ecadd31e8796a2c51e0531a2kess NameVirtualHost 192.0.2.1:80<br />
80c4526970a11f37c0f8e3b82afdf03902dac3f3slive <VirtualHost 192.0.2.1:80><br />
80c4526970a11f37c0f8e3b82afdf03902dac3f3slive </VirtualHost><br />
530eba85dbd41b8a0fa5255d3648d1440199a661slive <VirtualHost 192.0.2.1:80><br />
80c4526970a11f37c0f8e3b82afdf03902dac3f3slive </VirtualHost><br />
80c4526970a11f37c0f8e3b82afdf03902dac3f3slive <VirtualHost *:80><br />
80c4526970a11f37c0f8e3b82afdf03902dac3f3slive </VirtualHost><br />
530eba85dbd41b8a0fa5255d3648d1440199a661slive <VirtualHost *:80><br />
80c4526970a11f37c0f8e3b82afdf03902dac3f3slive </VirtualHost><br />
cf1595220a90759be0a39ab8b11c8cb834b698a9ianh </example>
cf1595220a90759be0a39ab8b11c8cb834b698a9ianh <p>If no matching virtual host is found, then the first listed
cf1595220a90759be0a39ab8b11c8cb834b698a9ianh virtual host that matches the IP address and port will be used.</p>
1a1cf0ee9229ee29e5750b25dd94dbb9b04072cfianh <p>IPv6 addresses must be enclosed in square brackets, as shown
1a1cf0ee9229ee29e5750b25dd94dbb9b04072cfianh in the following example:</p>
530eba85dbd41b8a0fa5255d3648d1440199a661slive NameVirtualHost [2001:db8::a00:20ff:fea7:ccea]:8080
1a1cf0ee9229ee29e5750b25dd94dbb9b04072cfianh </example>
80c4526970a11f37c0f8e3b82afdf03902dac3f3slive <note><title>Argument to <directive type="section">VirtualHost</directive>
80c4526970a11f37c0f8e3b82afdf03902dac3f3slive directive</title>
80c4526970a11f37c0f8e3b82afdf03902dac3f3slive exactly match the argument to the <directive
1a1cf0ee9229ee29e5750b25dd94dbb9b04072cfianh NameVirtualHost 192.0.2.2:80<br />
80c4526970a11f37c0f8e3b82afdf03902dac3f3slive <VirtualHost 192.0.2.2:80><br />
80c4526970a11f37c0f8e3b82afdf03902dac3f3slive # ...<br />
80c4526970a11f37c0f8e3b82afdf03902dac3f3slive </VirtualHost><br />
80c4526970a11f37c0f8e3b82afdf03902dac3f3slive</directivesynopsis>
80c4526970a11f37c0f8e3b82afdf03902dac3f3slive<directivesynopsis>
80c4526970a11f37c0f8e3b82afdf03902dac3f3slive<description>Configures what features are available in a particular
80c4526970a11f37c0f8e3b82afdf03902dac3f3slivedirectory</description>
fb77c505254b6e9c925e23e734463e87574f8f40kess<syntax>Options
80c4526970a11f37c0f8e3b82afdf03902dac3f3slive [+|-]<var>option</var> [[+|-]<var>option</var>] ...</syntax>
80c4526970a11f37c0f8e3b82afdf03902dac3f3slive<contextlist><context>server config</context><context>virtual host</context>
003f0c9fda6664daf5092a0e42f65ede20098153slive<context>directory</context><context>.htaccess</context>
80c4526970a11f37c0f8e3b82afdf03902dac3f3slive</contextlist>
313bb560bc5c323cfd40c9cad7335b4b8e060aedkess <p>The <directive>Options</directive> directive controls which
80c4526970a11f37c0f8e3b82afdf03902dac3f3slive server features are available in a particular directory.</p>
80c4526970a11f37c0f8e3b82afdf03902dac3f3slive <p><var>option</var> can be set to <code>None</code>, in which
a7f40ca49262952d6dd69d021cf5b0c2b452ae4cnd case none of the extra features are enabled, or one or more of
80c4526970a11f37c0f8e3b82afdf03902dac3f3slive the following:</p>
a7f40ca49262952d6dd69d021cf5b0c2b452ae4cnd <dd>All options except for <code>MultiViews</code>. This is the default
a7f40ca49262952d6dd69d021cf5b0c2b452ae4cnd setting.</dd>
313bb560bc5c323cfd40c9cad7335b4b8e060aedkess Execution of CGI scripts using <module>mod_cgi</module>
db1b819ff8966e3c6a5ca03c59a8ae06c2cecc9frbowen is permitted.</dd>
a7f40ca49262952d6dd69d021cf5b0c2b452ae4cnd The server will follow symbolic links in this directory.
c97e8972ab1f4dd167e3dc4db87daf91114009fbnd <p>Even though the server follows the symlink it does <em>not</em>
c97e8972ab1f4dd167e3dc4db87daf91114009fbnd change the pathname used to match against <directive type="section"
9f1dd1339447bf4b291682cd94bf9f28bc2685e0niq <p>Note also, that this option <strong>gets ignored</strong> if set
9f1dd1339447bf4b291682cd94bf9f28bc2685e0niq inside a <directive type="section" module="core">Location</directive>
9f1dd1339447bf4b291682cd94bf9f28bc2685e0niq section.</p>
80c4526970a11f37c0f8e3b82afdf03902dac3f3slive <p>Omitting this option should not be considered a security restriction,
db1b819ff8966e3c6a5ca03c59a8ae06c2cecc9frbowen since symlink testing is subject to race conditions that make it
db1b819ff8966e3c6a5ca03c59a8ae06c2cecc9frbowen circumventable.</p>
80c4526970a11f37c0f8e3b82afdf03902dac3f3slive Server-side includes provided by <module>mod_include</module>
80c4526970a11f37c0f8e3b82afdf03902dac3f3slive are permitted.</dd>
80c4526970a11f37c0f8e3b82afdf03902dac3f3slive Server-side includes are permitted, but the <code>#exec
80c4526970a11f37c0f8e3b82afdf03902dac3f3slive cmd</code> and <code>#exec cgi</code> are disabled. It is still
80c4526970a11f37c0f8e3b82afdf03902dac3f3slive possible to <code>#include virtual</code> CGI scripts from
80c4526970a11f37c0f8e3b82afdf03902dac3f3slive <directive module="mod_alias">ScriptAlias</directive>ed
80c4526970a11f37c0f8e3b82afdf03902dac3f3slive directories.</dd>
80c4526970a11f37c0f8e3b82afdf03902dac3f3slive If a URL which maps to a directory is requested, and there
80c4526970a11f37c0f8e3b82afdf03902dac3f3slive is no <directive module="mod_dir">DirectoryIndex</directive>
80c4526970a11f37c0f8e3b82afdf03902dac3f3slive (<em>e.g.</em>, <code>index.html</code>) in that directory, then
80c4526970a11f37c0f8e3b82afdf03902dac3f3slive <module>mod_autoindex</module> will return a formatted listing
80c4526970a11f37c0f8e3b82afdf03902dac3f3slive of the directory.</dd>
80c4526970a11f37c0f8e3b82afdf03902dac3f3slive <a href="/content-negotiation.html">Content negotiated</a>
80c4526970a11f37c0f8e3b82afdf03902dac3f3slive "MultiViews" are allowed using
003f0c9fda6664daf5092a0e42f65ede20098153slive <dd>The server will only follow symbolic links for which the
80c4526970a11f37c0f8e3b82afdf03902dac3f3slive target file or directory is owned by the same user id as the
80c4526970a11f37c0f8e3b82afdf03902dac3f3slive <note><title>Note</title> <p>This option gets ignored if
80c4526970a11f37c0f8e3b82afdf03902dac3f3slive <p>This option should not be considered a security restriction,
80c4526970a11f37c0f8e3b82afdf03902dac3f3slive since symlink testing is subject to race conditions that make it
a7f40ca49262952d6dd69d021cf5b0c2b452ae4cnd <p>Normally, if multiple <directive>Options</directive> could
130d299c4b2b15be45532a176604c71fdc7bea5bnd apply to a directory, then the most specific one is used and
130d299c4b2b15be45532a176604c71fdc7bea5bnd others are ignored; the options are not merged. (See <a
130d299c4b2b15be45532a176604c71fdc7bea5bnd href="/sections.html#mergin">how sections are merged</a>.)
130d299c4b2b15be45532a176604c71fdc7bea5bnd <directive>Options</directive> directive are preceded by a
a7f40ca49262952d6dd69d021cf5b0c2b452ae4cnd merged. Any options preceded by a <code>+</code> are added to the
80c4526970a11f37c0f8e3b82afdf03902dac3f3slive options currently in force, and any options preceded by a
80c4526970a11f37c0f8e3b82afdf03902dac3f3slive <code>-</code> are removed from the options currently in
80c4526970a11f37c0f8e3b82afdf03902dac3f3slive force. </p>
80c4526970a11f37c0f8e3b82afdf03902dac3f3slive <p>Mixing <directive>Options</directive> with a <code>+</code> or
80c4526970a11f37c0f8e3b82afdf03902dac3f3slive <code>-</code> with those without is not valid syntax, and is likely
80c4526970a11f37c0f8e3b82afdf03902dac3f3slive to cause unexpected results.</p>
003f0c9fda6664daf5092a0e42f65ede20098153slive <p>For example, without any <code>+</code> and <code>-</code> symbols:</p>
80c4526970a11f37c0f8e3b82afdf03902dac3f3slive Options Indexes FollowSymLinks<br />
b91096bcdd71fcbb37c9905f6cf79e930ae349b1jorton </Directory><br />
b91096bcdd71fcbb37c9905f6cf79e930ae349b1jorton Options Includes<br />
b91096bcdd71fcbb37c9905f6cf79e930ae349b1jorton </Directory>
b91096bcdd71fcbb37c9905f6cf79e930ae349b1jorton <p>then only <code>Includes</code> will be set for the
b91096bcdd71fcbb37c9905f6cf79e930ae349b1jorton <code>/web/docs/spec</code> directory. However if the second
80c4526970a11f37c0f8e3b82afdf03902dac3f3slive <directive>Options</directive> directive uses the <code>+</code> and
b91096bcdd71fcbb37c9905f6cf79e930ae349b1jorton Options Indexes FollowSymLinks<br />
b91096bcdd71fcbb37c9905f6cf79e930ae349b1jorton </Directory><br />
80c4526970a11f37c0f8e3b82afdf03902dac3f3slive Options +Includes -Indexes<br />
80c4526970a11f37c0f8e3b82afdf03902dac3f3slive </Directory>
12099dff89f3135d53929f4f1bdb42c7d044d928nd <code>Includes</code> are set for the <code>/web/docs/spec</code>
b00fe3c3354db01001b8eddfd9b88441380f837dwrowe directory.</p>
b00fe3c3354db01001b8eddfd9b88441380f837dwrowe <code>-Includes</code> disables server-side includes completely
b00fe3c3354db01001b8eddfd9b88441380f837dwrowe regardless of the previous setting.</p>
12099dff89f3135d53929f4f1bdb42c7d044d928nd <p>The default in the absence of any other settings is
12099dff89f3135d53929f4f1bdb42c7d044d928nd</directivesynopsis>
b00fe3c3354db01001b8eddfd9b88441380f837dwrowe<directivesynopsis>
b00fe3c3354db01001b8eddfd9b88441380f837dwrowe<description>Limits the CPU consumption of processes launched
b00fe3c3354db01001b8eddfd9b88441380f837dwroweby Apache httpd children</description>
b00fe3c3354db01001b8eddfd9b88441380f837dwrowe<syntax>RLimitCPU <var>seconds</var>|max [<var>seconds</var>|max]</syntax>
12099dff89f3135d53929f4f1bdb42c7d044d928nd<contextlist><context>server config</context><context>virtual host</context>
12099dff89f3135d53929f4f1bdb42c7d044d928nd<context>directory</context><context>.htaccess</context></contextlist>
80c4526970a11f37c0f8e3b82afdf03902dac3f3slive <p>Takes 1 or 2 parameters. The first parameter sets the soft
80c4526970a11f37c0f8e3b82afdf03902dac3f3slive resource limit for all processes and the second parameter sets
80c4526970a11f37c0f8e3b82afdf03902dac3f3slive the maximum resource limit. Either parameter can be a number,
80c4526970a11f37c0f8e3b82afdf03902dac3f3slive or <code>max</code> to indicate to the server that the limit should
fb77c505254b6e9c925e23e734463e87574f8f40kess be set to the maximum allowed by the operating system
fb294b146e7ceb48e3983ee3684ba6c6506241c0jim configuration. Raising the maximum resource limit requires that
80c4526970a11f37c0f8e3b82afdf03902dac3f3slive the server is running as <code>root</code>, or in the initial startup
80c4526970a11f37c0f8e3b82afdf03902dac3f3slive <p>This applies to processes forked off from Apache httpd children
a7f40ca49262952d6dd69d021cf5b0c2b452ae4cnd servicing requests, not the Apache httpd children themselves. This
a7f40ca49262952d6dd69d021cf5b0c2b452ae4cnd includes CGI scripts and SSI exec commands, but not any
313bb560bc5c323cfd40c9cad7335b4b8e060aedkess processes forked off from the Apache httpd parent such as piped
a7f40ca49262952d6dd69d021cf5b0c2b452ae4cnd <p>CPU resource limits are expressed in seconds per
a7f40ca49262952d6dd69d021cf5b0c2b452ae4cnd process.</p>
fb77c505254b6e9c925e23e734463e87574f8f40kess<seealso><directive module="core">RLimitMEM</directive></seealso>
80c4526970a11f37c0f8e3b82afdf03902dac3f3slive<seealso><directive module="core">RLimitNPROC</directive></seealso>
80c4526970a11f37c0f8e3b82afdf03902dac3f3slive</directivesynopsis>
313bb560bc5c323cfd40c9cad7335b4b8e060aedkess<directivesynopsis>
313bb560bc5c323cfd40c9cad7335b4b8e060aedkess<description>Limits the memory consumption of processes launched
3c6c63407f1855ddfc45ac69b69a2a9bf15135e6rbowenby Apache httpd children</description>
3c6c63407f1855ddfc45ac69b69a2a9bf15135e6rbowen<syntax>RLimitMEM <var>bytes</var>|max [<var>bytes</var>|max]</syntax>
80c4526970a11f37c0f8e3b82afdf03902dac3f3slive<default>Unset; uses operating system defaults</default>
80c4526970a11f37c0f8e3b82afdf03902dac3f3slive<contextlist><context>server config</context><context>virtual host</context>
80c4526970a11f37c0f8e3b82afdf03902dac3f3slive<context>directory</context><context>.htaccess</context></contextlist>
80c4526970a11f37c0f8e3b82afdf03902dac3f3slive <p>Takes 1 or 2 parameters. The first parameter sets the soft
80c4526970a11f37c0f8e3b82afdf03902dac3f3slive resource limit for all processes and the second parameter sets
80c4526970a11f37c0f8e3b82afdf03902dac3f3slive the maximum resource limit. Either parameter can be a number,
3c6c63407f1855ddfc45ac69b69a2a9bf15135e6rbowen or <code>max</code> to indicate to the server that the limit should
3c6c63407f1855ddfc45ac69b69a2a9bf15135e6rbowen be set to the maximum allowed by the operating system
3c6c63407f1855ddfc45ac69b69a2a9bf15135e6rbowen configuration. Raising the maximum resource limit requires that
3c6c63407f1855ddfc45ac69b69a2a9bf15135e6rbowen the server is running as <code>root</code>, or in the initial startup
fb77c505254b6e9c925e23e734463e87574f8f40kess phase.</p>
80c4526970a11f37c0f8e3b82afdf03902dac3f3slive <p>This applies to processes forked off from Apache httpd children
80c4526970a11f37c0f8e3b82afdf03902dac3f3slive servicing requests, not the Apache httpd children themselves. This
80c4526970a11f37c0f8e3b82afdf03902dac3f3slive includes CGI scripts and SSI exec commands, but not any
80c4526970a11f37c0f8e3b82afdf03902dac3f3slive processes forked off from the Apache httpd parent such as piped
80c4526970a11f37c0f8e3b82afdf03902dac3f3slive <p>Memory resource limits are expressed in bytes per
80c4526970a11f37c0f8e3b82afdf03902dac3f3slive process.</p>
130d299c4b2b15be45532a176604c71fdc7bea5bnd<seealso><directive module="core">RLimitCPU</directive></seealso>
130d299c4b2b15be45532a176604c71fdc7bea5bnd<seealso><directive module="core">RLimitNPROC</directive></seealso>
130d299c4b2b15be45532a176604c71fdc7bea5bnd</directivesynopsis>
80c4526970a11f37c0f8e3b82afdf03902dac3f3slive<directivesynopsis>
80c4526970a11f37c0f8e3b82afdf03902dac3f3slive<description>Limits the number of processes that can be launched by
a38b5f73e7f0f3b8726fb47d27b145f37036ead0jimprocesses launched by Apache httpd children</description>
a38b5f73e7f0f3b8726fb47d27b145f37036ead0jim<syntax>RLimitNPROC <var>number</var>|max [<var>number</var>|max]</syntax>
a38b5f73e7f0f3b8726fb47d27b145f37036ead0jim<contextlist><context>server config</context><context>virtual host</context>
a38b5f73e7f0f3b8726fb47d27b145f37036ead0jim<context>directory</context><context>.htaccess</context></contextlist>
a38b5f73e7f0f3b8726fb47d27b145f37036ead0jim <p>Takes 1 or 2 parameters. The first parameter sets the soft
a38b5f73e7f0f3b8726fb47d27b145f37036ead0jim resource limit for all processes and the second parameter sets
a38b5f73e7f0f3b8726fb47d27b145f37036ead0jim the maximum resource limit. Either parameter can be a number,
a38b5f73e7f0f3b8726fb47d27b145f37036ead0jim or <code>max</code> to indicate to the server that the limit
a38b5f73e7f0f3b8726fb47d27b145f37036ead0jim should be set to the maximum allowed by the operating system
a38b5f73e7f0f3b8726fb47d27b145f37036ead0jim configuration. Raising the maximum resource limit requires that
a38b5f73e7f0f3b8726fb47d27b145f37036ead0jim the server is running as <code>root</code>, or in the initial startup
a38b5f73e7f0f3b8726fb47d27b145f37036ead0jim phase.</p>
a38b5f73e7f0f3b8726fb47d27b145f37036ead0jim <p>This applies to processes forked off from Apache httpd children
a38b5f73e7f0f3b8726fb47d27b145f37036ead0jim servicing requests, not the Apache httpd children themselves. This
a38b5f73e7f0f3b8726fb47d27b145f37036ead0jim includes CGI scripts and SSI exec commands, but not any
a38b5f73e7f0f3b8726fb47d27b145f37036ead0jim processes forked off from the Apache httpd parent such as piped
a38b5f73e7f0f3b8726fb47d27b145f37036ead0jim <p>Process limits control the number of processes per user.</p>
b3ec2c7988894fc3722521c0a61fcb2ddab31c33colm under user ids other than the web server user id, this directive
a38b5f73e7f0f3b8726fb47d27b145f37036ead0jim will limit the number of processes that the server itself can
a38b5f73e7f0f3b8726fb47d27b145f37036ead0jim create. Evidence of this situation will be indicated by
a38b5f73e7f0f3b8726fb47d27b145f37036ead0jim <strong><code>cannot fork</code></strong> messages in the
a38b5f73e7f0f3b8726fb47d27b145f37036ead0jim<seealso><directive module="core">RLimitMEM</directive></seealso>
a38b5f73e7f0f3b8726fb47d27b145f37036ead0jim<seealso><directive module="core">RLimitCPU</directive></seealso>
a38b5f73e7f0f3b8726fb47d27b145f37036ead0jim</directivesynopsis>
a38b5f73e7f0f3b8726fb47d27b145f37036ead0jim<directivesynopsis>
a38b5f73e7f0f3b8726fb47d27b145f37036ead0jim<description>Technique for locating the interpreter for CGI
a38b5f73e7f0f3b8726fb47d27b145f37036ead0jimscripts</description>
a38b5f73e7f0f3b8726fb47d27b145f37036ead0jim<syntax>ScriptInterpreterSource Registry|Registry-Strict|Script</syntax>
a38b5f73e7f0f3b8726fb47d27b145f37036ead0jim<contextlist><context>server config</context><context>virtual host</context>
a38b5f73e7f0f3b8726fb47d27b145f37036ead0jim<context>directory</context><context>.htaccess</context></contextlist>
80c4526970a11f37c0f8e3b82afdf03902dac3f3slive<compatibility>Win32 only;
80c4526970a11f37c0f8e3b82afdf03902dac3f3sliveoption <code>Registry-Strict</code> is available in Apache HTTP Server 2.0 and
80c4526970a11f37c0f8e3b82afdf03902dac3f3slivelater</compatibility>
80c4526970a11f37c0f8e3b82afdf03902dac3f3slive <p>This directive is used to control how Apache httpd finds the
80c4526970a11f37c0f8e3b82afdf03902dac3f3slive interpreter used to run CGI scripts. The default setting is
313bb560bc5c323cfd40c9cad7335b4b8e060aedkess <code>Script</code>. This causes Apache httpd to use the interpreter pointed to
80c4526970a11f37c0f8e3b82afdf03902dac3f3slive by the shebang line (first line, starting with <code>#!</code>) in the
a7f40ca49262952d6dd69d021cf5b0c2b452ae4cnd script. On Win32 systems this line usually looks like:</p>
80c4526970a11f37c0f8e3b82afdf03902dac3f3slive <p>or, if <code>perl</code> is in the <code>PATH</code>, simply:</p>
a7f40ca49262952d6dd69d021cf5b0c2b452ae4cnd <p>Setting <code>ScriptInterpreterSource Registry</code> will
80c4526970a11f37c0f8e3b82afdf03902dac3f3slive cause the Windows Registry tree <code>HKEY_CLASSES_ROOT</code> to be
80c4526970a11f37c0f8e3b82afdf03902dac3f3slive searched using the script file extension (e.g., <code>.pl</code>) as a
a23acbbd61b9565caecea9931b6bcdf0b6228cbbslive search key. The command defined by the registry subkey
80c4526970a11f37c0f8e3b82afdf03902dac3f3slive <code>Shell\ExecCGI\Command</code> or, if it does not exist, by the subkey
80c4526970a11f37c0f8e3b82afdf03902dac3f3slive <code>Shell\Open\Command</code> is used to open the script file. If the
01710fa5f312f3a9cd1969d1809cf6c19a7f3d31niq registry keys cannot be found, Apache httpd falls back to the behavior of the
a23acbbd61b9565caecea9931b6bcdf0b6228cbbslive <p>Be careful when using <code>ScriptInterpreterSource
a23acbbd61b9565caecea9931b6bcdf0b6228cbbslive module="mod_alias">ScriptAlias</directive>'ed directories, because
80c4526970a11f37c0f8e3b82afdf03902dac3f3slive Apache httpd will try to execute <strong>every</strong> file within this
313bb560bc5c323cfd40c9cad7335b4b8e060aedkess directory. The <code>Registry</code> setting may cause undesired
a7f40ca49262952d6dd69d021cf5b0c2b452ae4cnd program calls on files which are typically not executed. For
a7f40ca49262952d6dd69d021cf5b0c2b452ae4cnd example, the default open command on <code>.htm</code> files on
130d299c4b2b15be45532a176604c71fdc7bea5bnd most Windows systems will execute Microsoft Internet Explorer, so
e8811b6d38f756b325446ded5d96857d13856511takashi any HTTP request for an <code>.htm</code> file existing within the
e8811b6d38f756b325446ded5d96857d13856511takashi script directory would start the browser in the background on the
e8811b6d38f756b325446ded5d96857d13856511takashi server. This is a good way to crash your system within a minute or
a7f40ca49262952d6dd69d021cf5b0c2b452ae4cnd <p>The option <code>Registry-Strict</code> which is new in Apache HTTP Server
a7f40ca49262952d6dd69d021cf5b0c2b452ae4cnd 2.0 does the same thing as <code>Registry</code> but uses only the
313bb560bc5c323cfd40c9cad7335b4b8e060aedkess <code>ExecCGI</code> key is not a common one. It must be
a7f40ca49262952d6dd69d021cf5b0c2b452ae4cnd configured manually in the windows registry and hence prevents
a7f40ca49262952d6dd69d021cf5b0c2b452ae4cnd accidental program calls on your system.</p>
a7f40ca49262952d6dd69d021cf5b0c2b452ae4cnd</directivesynopsis>
cf02129aebf73dd0bdf369b172eb481ff76ac5f6colm<directivesynopsis>
130d299c4b2b15be45532a176604c71fdc7bea5bnd<description>Determine if mod_status displays the first 63 characters
130d299c4b2b15be45532a176604c71fdc7bea5bndof a request or the last 63, assuming the request itself is greater than
130d299c4b2b15be45532a176604c71fdc7bea5bnd63 chars.</description>
130d299c4b2b15be45532a176604c71fdc7bea5bnd<contextlist><context>server config</context></contextlist>
a7f40ca49262952d6dd69d021cf5b0c2b452ae4cnd<compatibility>Available in Apache httpd 2.2.7 and later.</compatibility>
80c4526970a11f37c0f8e3b82afdf03902dac3f3slive displays the actual request being handled.
80c4526970a11f37c0f8e3b82afdf03902dac3f3slive For historical purposes, only 63 characters of the request
80c4526970a11f37c0f8e3b82afdf03902dac3f3slive are actually stored for display purposes. This directive
80c4526970a11f37c0f8e3b82afdf03902dac3f3slive controls whether the 1st 63 characters are stored (the previous
313bb560bc5c323cfd40c9cad7335b4b8e060aedkess behavior and the default) or if the last 63 characters are. This
a23acbbd61b9565caecea9931b6bcdf0b6228cbbslive is only applicable, of course, if the length of the request is
80c4526970a11f37c0f8e3b82afdf03902dac3f3slive 64 characters or greater.</p>
fb77c505254b6e9c925e23e734463e87574f8f40kess >GET /disk1/storage/apache/htdocs/images/imagestore1/food/apples.jpg HTTP/1.1</code
130d299c4b2b15be45532a176604c71fdc7bea5bnd > mod_status displays as follows:
80c4526970a11f37c0f8e3b82afdf03902dac3f3slive <td>GET /disk1/storage/apache/htdocs/images/imagestore1/food/apples</td>
a23acbbd61b9565caecea9931b6bcdf0b6228cbbslive <td>orage/apache/htdocs/images/imagestore1/food/apples.jpg HTTP/1.1</td>
a23acbbd61b9565caecea9931b6bcdf0b6228cbbslive</directivesynopsis>
80c4526970a11f37c0f8e3b82afdf03902dac3f3slive<directivesynopsis>
80c4526970a11f37c0f8e3b82afdf03902dac3f3slive<description>Email address that the server includes in error
80c4526970a11f37c0f8e3b82afdf03902dac3f3slivemessages sent to the client</description>
80c4526970a11f37c0f8e3b82afdf03902dac3f3slive<syntax>ServerAdmin <var>email-address</var>|<var>URL</var></syntax>
80c4526970a11f37c0f8e3b82afdf03902dac3f3slive<contextlist><context>server config</context><context>virtual host</context>
80c4526970a11f37c0f8e3b82afdf03902dac3f3slive</contextlist>
4cf1c07a88ef51e11570c775507cd7d2c3e35a97slive <p>The <directive>ServerAdmin</directive> sets the contact address
4cf1c07a88ef51e11570c775507cd7d2c3e35a97slive that the server includes in any error messages it returns to the
4cf1c07a88ef51e11570c775507cd7d2c3e35a97slive client. If the <code>httpd</code> doesn't recognize the supplied argument
4cf1c07a88ef51e11570c775507cd7d2c3e35a97slive as an URL, it
130d299c4b2b15be45532a176604c71fdc7bea5bnd assumes, that it's an <var>email-address</var> and prepends it with
130d299c4b2b15be45532a176604c71fdc7bea5bnd <code>mailto:</code> in hyperlink targets. However, it's recommended to
130d299c4b2b15be45532a176604c71fdc7bea5bnd actually use an email address, since there are a lot of CGI scripts that
9b5e2c5e769dc678a1aca06df75c32022b2f1492trawick make that assumption. If you want to use an URL, it should point to another
80c4526970a11f37c0f8e3b82afdf03902dac3f3slive server under your control. Otherwise users may not be able to contact you in
130d299c4b2b15be45532a176604c71fdc7bea5bnd case of errors.</p>
80c4526970a11f37c0f8e3b82afdf03902dac3f3slive <p>It may be worth setting up a dedicated address for this, e.g.</p>
80c4526970a11f37c0f8e3b82afdf03902dac3f3slive ServerAdmin www-admin@foo.example.com
313bb560bc5c323cfd40c9cad7335b4b8e060aedkess <p>as users do not always mention that they are talking about the
313bb560bc5c323cfd40c9cad7335b4b8e060aedkess server!</p>
80c4526970a11f37c0f8e3b82afdf03902dac3f3slive</directivesynopsis>
7db9f691a00ead175b03335457ca296a33ddf31bnd<directivesynopsis>
<syntax>ServerName [<var>scheme</var>://]<var>fully-qualified-domain-name</var>[:<var>port</var>]</syntax>
ServerName www.example.com:80
settings which determine whether self-referential URLs (e.g., by the
httpd: Could not reliably determine the server's fully qualified domain name, using rocinante.local for ServerName
href="http://httpd.apache.org/docs/misc/FAQ.html#prompted-twice">the