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8 <title>core - Apache HTTP Server</title>
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14 <div id="page-header">
15 <p class="menu"><a href="../mod/">Modules</a> | <a href="../mod/directives.html">Directives</a> | <a href="../faq/">FAQ</a> | <a href="../glossary.html">Glossary</a> | <a href="../sitemap.html">Sitemap</a></p>
16 <p class="apache">Apache HTTP Server Version 2.1</p>
17 <img alt="" src="../images/feather.gif" /></div>
18 <div class="up"><a href="./"><img title="<-" alt="<-" src="../images/left.gif" /></a></div>
20 <a href="http://www.apache.org/">Apache</a> > <a href="http://httpd.apache.org/">HTTP Server</a> > <a href="http://httpd.apache.org/docs-project/">Documentation</a> > <a href="../">Version 2.1</a> > <a href="./">Modules</a></div>
21 <div id="page-content">
22 <div id="preamble"><h1>Apache Core Features</h1>
24 <p><span>Available Languages: </span><a href="../de/mod/core.html"> de </a> | <a href="../en/mod/core.html"> en </a></p>
26 <table class="module"><tr><th><a href="module-dict.html#Description">Description:</a></th><td>Core Apache HTTP Server features that are always
28 <tr><th><a href="module-dict.html#Status">Status:</a></th><td>Core</td></tr></table>
30 <div id="quickview"><h3 class="directives">Directives</h3>
32 <li><img alt="" src="../images/down.gif" /> <a href="#acceptpathinfo">AcceptPathInfo</a></li>
33 <li><img alt="" src="../images/down.gif" /> <a href="#accessfilename">AccessFileName</a></li>
34 <li><img alt="" src="../images/down.gif" /> <a href="#adddefaultcharset">AddDefaultCharset</a></li>
35 <li><img alt="" src="../images/down.gif" /> <a href="#addoutputfilterbytype">AddOutputFilterByType</a></li>
36 <li><img alt="" src="../images/down.gif" /> <a href="#allowoverride">AllowOverride</a></li>
37 <li><img alt="" src="../images/down.gif" /> <a href="#authname">AuthName</a></li>
38 <li><img alt="" src="../images/down.gif" /> <a href="#authtype">AuthType</a></li>
39 <li><img alt="" src="../images/down.gif" /> <a href="#cgimapextension">CGIMapExtension</a></li>
40 <li><img alt="" src="../images/down.gif" /> <a href="#contentdigest">ContentDigest</a></li>
41 <li><img alt="" src="../images/down.gif" /> <a href="#defaulttype">DefaultType</a></li>
42 <li><img alt="" src="../images/down.gif" /> <a href="#directory"><Directory></a></li>
43 <li><img alt="" src="../images/down.gif" /> <a href="#directorymatch"><DirectoryMatch></a></li>
44 <li><img alt="" src="../images/down.gif" /> <a href="#documentroot">DocumentRoot</a></li>
45 <li><img alt="" src="../images/down.gif" /> <a href="#enablemmap">EnableMMAP</a></li>
46 <li><img alt="" src="../images/down.gif" /> <a href="#enablesendfile">EnableSendfile</a></li>
47 <li><img alt="" src="../images/down.gif" /> <a href="#errordocument">ErrorDocument</a></li>
48 <li><img alt="" src="../images/down.gif" /> <a href="#errorlog">ErrorLog</a></li>
49 <li><img alt="" src="../images/down.gif" /> <a href="#fileetag">FileETag</a></li>
50 <li><img alt="" src="../images/down.gif" /> <a href="#files"><Files></a></li>
51 <li><img alt="" src="../images/down.gif" /> <a href="#filesmatch"><FilesMatch></a></li>
52 <li><img alt="" src="../images/down.gif" /> <a href="#forcetype">ForceType</a></li>
53 <li><img alt="" src="../images/down.gif" /> <a href="#hostnamelookups">HostnameLookups</a></li>
54 <li><img alt="" src="../images/down.gif" /> <a href="#ifdefine"><IfDefine></a></li>
55 <li><img alt="" src="../images/down.gif" /> <a href="#ifmodule"><IfModule></a></li>
56 <li><img alt="" src="../images/down.gif" /> <a href="#include">Include</a></li>
57 <li><img alt="" src="../images/down.gif" /> <a href="#keepalive">KeepAlive</a></li>
58 <li><img alt="" src="../images/down.gif" /> <a href="#keepalivetimeout">KeepAliveTimeout</a></li>
59 <li><img alt="" src="../images/down.gif" /> <a href="#limit"><Limit></a></li>
60 <li><img alt="" src="../images/down.gif" /> <a href="#limitexcept"><LimitExcept></a></li>
61 <li><img alt="" src="../images/down.gif" /> <a href="#limitrequestbody">LimitRequestBody</a></li>
62 <li><img alt="" src="../images/down.gif" /> <a href="#limitrequestfields">LimitRequestFields</a></li>
63 <li><img alt="" src="../images/down.gif" /> <a href="#limitrequestfieldsize">LimitRequestFieldSize</a></li>
64 <li><img alt="" src="../images/down.gif" /> <a href="#limitrequestline">LimitRequestLine</a></li>
65 <li><img alt="" src="../images/down.gif" /> <a href="#limitxmlrequestbody">LimitXMLRequestBody</a></li>
66 <li><img alt="" src="../images/down.gif" /> <a href="#location"><Location></a></li>
67 <li><img alt="" src="../images/down.gif" /> <a href="#locationmatch"><LocationMatch></a></li>
68 <li><img alt="" src="../images/down.gif" /> <a href="#loglevel">LogLevel</a></li>
69 <li><img alt="" src="../images/down.gif" /> <a href="#maxkeepaliverequests">MaxKeepAliveRequests</a></li>
70 <li><img alt="" src="../images/down.gif" /> <a href="#namevirtualhost">NameVirtualHost</a></li>
71 <li><img alt="" src="../images/down.gif" /> <a href="#options">Options</a></li>
72 <li><img alt="" src="../images/down.gif" /> <a href="#require">Require</a></li>
73 <li><img alt="" src="../images/down.gif" /> <a href="#rlimitcpu">RLimitCPU</a></li>
74 <li><img alt="" src="../images/down.gif" /> <a href="#rlimitmem">RLimitMEM</a></li>
75 <li><img alt="" src="../images/down.gif" /> <a href="#rlimitnproc">RLimitNPROC</a></li>
76 <li><img alt="" src="../images/down.gif" /> <a href="#satisfy">Satisfy</a></li>
77 <li><img alt="" src="../images/down.gif" /> <a href="#scriptinterpretersource">ScriptInterpreterSource</a></li>
78 <li><img alt="" src="../images/down.gif" /> <a href="#serveradmin">ServerAdmin</a></li>
79 <li><img alt="" src="../images/down.gif" /> <a href="#serveralias">ServerAlias</a></li>
80 <li><img alt="" src="../images/down.gif" /> <a href="#servername">ServerName</a></li>
81 <li><img alt="" src="../images/down.gif" /> <a href="#serverpath">ServerPath</a></li>
82 <li><img alt="" src="../images/down.gif" /> <a href="#serverroot">ServerRoot</a></li>
83 <li><img alt="" src="../images/down.gif" /> <a href="#serversignature">ServerSignature</a></li>
84 <li><img alt="" src="../images/down.gif" /> <a href="#servertokens">ServerTokens</a></li>
85 <li><img alt="" src="../images/down.gif" /> <a href="#sethandler">SetHandler</a></li>
86 <li><img alt="" src="../images/down.gif" /> <a href="#setinputfilter">SetInputFilter</a></li>
87 <li><img alt="" src="../images/down.gif" /> <a href="#setoutputfilter">SetOutputFilter</a></li>
88 <li><img alt="" src="../images/down.gif" /> <a href="#timeout">TimeOut</a></li>
89 <li><img alt="" src="../images/down.gif" /> <a href="#usecanonicalname">UseCanonicalName</a></li>
90 <li><img alt="" src="../images/down.gif" /> <a href="#virtualhost"><VirtualHost></a></li>
94 <div class="top"><a href="#page-header"><img alt="top" src="../images/up.gif" /></a></div>
95 <div class="directive-section"><h2><a name="AcceptPathInfo" id="AcceptPathInfo">AcceptPathInfo</a> <a name="acceptpathinfo" id="acceptpathinfo">Directive</a></h2>
96 <table class="directive">
97 <tr><th><a href="directive-dict.html#Description">Description:</a></th><td>Resources accept trailing pathname information</td></tr>
98 <tr><th><a href="directive-dict.html#Syntax">Syntax:</a></th><td><code>AcceptPathInfo On|Off|Default</code></td></tr>
99 <tr><th><a href="directive-dict.html#Default">Default:</a></th><td><code>AcceptPathInfo Default</code></td></tr>
100 <tr><th><a href="directive-dict.html#Context">Context:</a></th><td>server config, virtual host, directory, .htaccess</td></tr>
101 <tr><th><a href="directive-dict.html#Override">Override:</a></th><td>FileInfo</td></tr>
102 <tr><th><a href="directive-dict.html#Status">Status:</a></th><td>Core</td></tr>
103 <tr><th><a href="directive-dict.html#Module">Module:</a></th><td>core</td></tr>
104 <tr><th><a href="directive-dict.html#Compatibility">Compatibility:</a></th><td>Available in Apache 2.0.30 and later</td></tr>
107 <p>This directive controls whether requests that contain trailing
108 pathname information that follows an actual filename (or
109 non-existent file in an existing directory) will be accepted or
110 rejected. The trailing pathname information can be made
111 available to scripts in the <code>PATH_INFO</code> environment
114 <p>For example, assume the location <code>/test/</code> points to
115 a directory that contains only the single file
116 <code>here.html</code>. Then requests for
117 <code>/test/here.html/more</code> and
118 <code>/test/nothere.html/more</code> both collect
119 <code>/more</code> as <code>PATH_INFO</code>.</p>
121 <p>The three possible arguments for the
122 <code class="directive">AcceptPathInfo</code> directive are:</p>
124 <dt><code>Off</code></dt><dd>A request will only be accepted if it
125 maps to a literal path that exists. Therefore a request with
126 trailing pathname information after the true filename such as
127 <code>/test/here.html/more</code> in the above example will return
128 a 404 NOT FOUND error.</dd>
130 <dt><code>On</code></dt><dd>A request will be accepted if a
131 leading path component maps to a file that exists. The above
132 example <code>/test/here.html/more</code> will be accepted if
133 <code>/test/here.html</code> maps to a valid file.</dd>
135 <dt><code>Default</code></dt><dd>The treatment of requests with
136 trailing pathname information is determined by the <a href="../handler.html">handler</a> responsible for the request.
137 The core handler for normal files defaults to rejecting
138 <code>PATH_INFO</code> requests. Handlers that serve scripts, such as <a href="mod_cgi.html">cgi-script</a> and <a href="mod_isapi.html">isapi-isa</a>, generally accept
139 <code>PATH_INFO</code> by default.</dd>
142 <p>The primary purpose of the <code>AcceptPathInfo</code>
143 directive is to allow you to override the handler's choice of
144 accepting or rejecting <code>PATH_INFO</code>. This override is required,
145 for example, when you use a <a href="../filter.html">filter</a>, such
146 as <a href="mod_include.html">INCLUDES</a>, to generate content
147 based on <code>PATH_INFO</code>. The core handler would usually reject
148 the request, so you can use the following configuration to enable
151 <div class="example"><p><code>
152 <Files "mypaths.shtml"><br />
153 <span class="indent">
154 Options +Includes<br />
155 SetOutputFilter INCLUDES<br />
156 AcceptPathInfo On<br />
163 <div class="top"><a href="#page-header"><img alt="top" src="../images/up.gif" /></a></div>
164 <div class="directive-section"><h2><a name="AccessFileName" id="AccessFileName">AccessFileName</a> <a name="accessfilename" id="accessfilename">Directive</a></h2>
165 <table class="directive">
166 <tr><th><a href="directive-dict.html#Description">Description:</a></th><td>Name of the distributed configuration file</td></tr>
167 <tr><th><a href="directive-dict.html#Syntax">Syntax:</a></th><td><code>AccessFileName <var>filename</var> [<var>filename</var>] ...</code></td></tr>
168 <tr><th><a href="directive-dict.html#Default">Default:</a></th><td><code>AccessFileName .htaccess</code></td></tr>
169 <tr><th><a href="directive-dict.html#Context">Context:</a></th><td>server config, virtual host</td></tr>
170 <tr><th><a href="directive-dict.html#Status">Status:</a></th><td>Core</td></tr>
171 <tr><th><a href="directive-dict.html#Module">Module:</a></th><td>core</td></tr>
173 <p>While processing a request the server looks for
174 the first existing configuration file from this list of names in
175 every directory of the path to the document, if distributed
176 configuration files are <a href="#allowoverride">enabled for that
177 directory</a>. For example:</p>
179 <div class="example"><p><code>
183 <p>before returning the document
184 <code>/usr/local/web/index.html</code>, the server will read
185 <code>/.acl</code>, <code>/usr/.acl</code>,
186 <code>/usr/local/.acl</code> and <code>/usr/local/web/.acl</code>
187 for directives, unless they have been disabled with</p>
189 <div class="example"><p><code>
190 <Directory /><br />
191 <span class="indent">
192 AllowOverride None<br />
199 <li><code class="directive"><a href="#allowoverride">AllowOverride</a></code></li>
200 <li><a href="../configuring.html">Configuration Files</a></li>
201 <li><a href="../howto/htaccess.html">.htaccess Files</a></li>
204 <div class="top"><a href="#page-header"><img alt="top" src="../images/up.gif" /></a></div>
205 <div class="directive-section"><h2><a name="AddDefaultCharset" id="AddDefaultCharset">AddDefaultCharset</a> <a name="adddefaultcharset" id="adddefaultcharset">Directive</a></h2>
206 <table class="directive">
207 <tr><th><a href="directive-dict.html#Description">Description:</a></th><td>Default character set to be added for a
208 response without an explicit character set</td></tr>
209 <tr><th><a href="directive-dict.html#Syntax">Syntax:</a></th><td><code>AddDefaultCharset On|Off|<var>charset</var></code></td></tr>
210 <tr><th><a href="directive-dict.html#Default">Default:</a></th><td><code>AddDefaultCharset Off</code></td></tr>
211 <tr><th><a href="directive-dict.html#Context">Context:</a></th><td>server config, virtual host, directory, .htaccess</td></tr>
212 <tr><th><a href="directive-dict.html#Override">Override:</a></th><td>FileInfo</td></tr>
213 <tr><th><a href="directive-dict.html#Status">Status:</a></th><td>Core</td></tr>
214 <tr><th><a href="directive-dict.html#Module">Module:</a></th><td>core</td></tr>
216 <p>This directive specifies the name of the character set that
217 will be added to any response that does not have any parameter on
218 the content type in the HTTP headers. This will override any
219 character set specified in the body of the document via a
220 <code>META</code> tag. A setting of <code>AddDefaultCharset
221 Off</code> disables this
222 functionality. <code>AddDefaultCharset On</code> enables
223 Apache's internal default charset of <code>iso-8859-1</code> as
224 required by the directive. You can also specify an alternate
225 <var>charset</var> to be used. For example:</p>
227 <div class="example"><p><code>
228 AddDefaultCharset utf-8
232 <div class="top"><a href="#page-header"><img alt="top" src="../images/up.gif" /></a></div>
233 <div class="directive-section"><h2><a name="AddOutputFilterByType" id="AddOutputFilterByType">AddOutputFilterByType</a> <a name="addoutputfilterbytype" id="addoutputfilterbytype">Directive</a></h2>
234 <table class="directive">
235 <tr><th><a href="directive-dict.html#Description">Description:</a></th><td>assigns an output filter to a particular MIME-type</td></tr>
236 <tr><th><a href="directive-dict.html#Syntax">Syntax:</a></th><td><code>AddOutputFilterByType <var>filter</var>[;<var>filter</var>...]
237 <var>MIME-type</var> [<var>MIME-type</var>] ...</code></td></tr>
238 <tr><th><a href="directive-dict.html#Context">Context:</a></th><td>server config, virtual host, directory, .htaccess</td></tr>
239 <tr><th><a href="directive-dict.html#Override">Override:</a></th><td>FileInfo</td></tr>
240 <tr><th><a href="directive-dict.html#Status">Status:</a></th><td>Core</td></tr>
241 <tr><th><a href="directive-dict.html#Module">Module:</a></th><td>core</td></tr>
242 <tr><th><a href="directive-dict.html#Compatibility">Compatibility:</a></th><td>Available in Apache 2.0.33 and later</td></tr>
244 <p>This directive activates a particular output <a href="../filter.html">filter</a> for a request depending on the
245 response MIME-type.</p>
247 <p>The following example uses the <code>DEFLATE</code> filter, which
248 is provided by <code class="module"><a href="../mod/mod_deflate.html">mod_deflate</a></code>. It will compress all
249 output (either static or dynamic) which is labeled as
250 <code>text/html</code> or <code>text/plain</code> before it is sent
253 <div class="example"><p><code>
254 AddOutputFilterByType DEFLATE text/html text/plain
257 <p>If you want the content to be processed by more than one filter, their
258 names have to be separated by semicolons. It's also possible to use one
259 <code class="directive">AddOutputFilterByType</code> directive for each of
262 <p>The configuration below causes all script output labeled as
263 <code>text/html</code> to be processed at first by the
264 <code>INCLUDES</code> filter and then by the <code>DEFLATE</code>
267 <div class="example"><p><code>
268 <Location /cgi-bin/><br />
269 <span class="indent">
270 Options Includes<br />
271 AddOutputFilterByType INCLUDES;DEFLATE text/html<br />
276 <div class="warning"><h3>Note</h3>
277 <p>Enabling filters with <code class="directive">AddOutputFilterByType</code>
278 may fail partially or completely in some cases. For expample, no
279 filters are applied if the MIME-type could not be determined and falls
280 back to the <code class="directive"><a href="#defaulttype">DefaultType</a></code> setting,
281 even if the <code class="directive"><a href="#defaulttype">DefaultType</a></code> is the
284 <p>However, if you want to make sure, that the filters will be
285 applied, assign the content type to a resource explicitely, for
286 example with <code class="directive"><a href="../mod/mod_mime.html#addtype">AddType</a></code> or
287 <code class="directive"><a href="#forcetype">ForceType</a></code>. Setting the
288 content type within a (non-nph) CGI script is also safe.</p>
290 <p>The by-type output filters are never applied on proxy requests.</p>
295 <li><code class="directive"><a href="../mod/mod_mime.html#addoutputfilter">AddOutputFilter</a></code></li>
296 <li><code class="directive"><a href="#setoutputfilter">SetOutputFilter</a></code></li>
297 <li><a href="../filter.html">filters</a></li>
300 <div class="top"><a href="#page-header"><img alt="top" src="../images/up.gif" /></a></div>
301 <div class="directive-section"><h2><a name="AllowOverride" id="AllowOverride">AllowOverride</a> <a name="allowoverride" id="allowoverride">Directive</a></h2>
302 <table class="directive">
303 <tr><th><a href="directive-dict.html#Description">Description:</a></th><td>Types of directives that are allowed in
304 .htaccess files</td></tr>
305 <tr><th><a href="directive-dict.html#Syntax">Syntax:</a></th><td><code>AllowOverride All|None|<var>directive-type</var>
306 [<var>directive-type</var>] ...</code></td></tr>
307 <tr><th><a href="directive-dict.html#Default">Default:</a></th><td><code>AllowOverride All</code></td></tr>
308 <tr><th><a href="directive-dict.html#Context">Context:</a></th><td>directory</td></tr>
309 <tr><th><a href="directive-dict.html#Status">Status:</a></th><td>Core</td></tr>
310 <tr><th><a href="directive-dict.html#Module">Module:</a></th><td>core</td></tr>
312 <p>When the server finds an <code>.htaccess</code> file (as
313 specified by <code class="directive"><a href="#accessfilename">AccessFileName</a></code>)
314 it needs to know which directives declared in that file can override
315 earlier configuration directives.</p>
317 <div class="note"><h3>Only available in <Directory> sections</h3>
318 <code class="directive">AllowOverride</code> is valid only in
319 <code class="directive"><a href="#directory"><Directory></a></code>
320 sections, not in <code class="directive"><a href="#location"><Location></a></code> or <code class="directive"><a href="#files"><Files></a></code> sections.
323 <p>When this directive is set to <code>None</code>, then
324 <a href="#accessfilename">.htaccess</a> files are completely ignored.
325 In this case, the server will not even attempt to read
326 <code>.htaccess</code> files in the filesystem.</p>
328 <p>When this directive is set to <code>All</code>, then any
329 directive which has the .htaccess <a href="directive-dict.html#Context">Context</a> is allowed in
330 <code>.htaccess</code> files.</p>
332 <p>The <var>directive-type</var> can be one of the following
333 groupings of directives.</p>
340 Allow use of the authorization directives (<code class="directive"><a href="../mod/mod_authn_dbm.html#authdbmgroupfile">AuthDBMGroupFile</a></code>,
341 <code class="directive"><a href="../mod/mod_authn_dbm.html#authdbmuserfile">AuthDBMUserFile</a></code>,
342 <code class="directive"><a href="../mod/mod_authz_groupfile.html#authgroupfile">AuthGroupFile</a></code>,
343 <code class="directive"><a href="#authname">AuthName</a></code>,
344 <code class="directive"><a href="#authtype">AuthType</a></code>, <code class="directive"><a href="../mod/mod_authn_file.html#authuserfile">AuthUserFile</a></code>, <code class="directive"><a href="#require">Require</a></code>, <em>etc.</em>).</dd>
349 Allow use of the directives controlling document types (<code class="directive"><a href="#defaulttype">DefaultType</a></code>, <code class="directive"><a href="#errordocument">ErrorDocument</a></code>, <code class="directive"><a href="#forcetype">ForceType</a></code>, <code class="directive"><a href="../mod/mod_negotiation.html#languagepriority">LanguagePriority</a></code>,
350 <code class="directive"><a href="#sethandler">SetHandler</a></code>, <code class="directive"><a href="#setinputfilter">SetInputFilter</a></code>, <code class="directive"><a href="#setoutputfilter">SetOutputFilter</a></code>, and
351 <code class="module"><a href="../mod/mod_mime.html">mod_mime</a></code> Add* and Remove*
352 directives, <em>etc.</em>).</dd>
357 Allow use of the directives controlling directory indexing
358 (<code class="directive"><a href="../mod/mod_autoindex.html#adddescription">AddDescription</a></code>,
359 <code class="directive"><a href="../mod/mod_autoindex.html#addicon">AddIcon</a></code>, <code class="directive"><a href="../mod/mod_autoindex.html#addiconbyencoding">AddIconByEncoding</a></code>,
360 <code class="directive"><a href="../mod/mod_autoindex.html#addiconbytype">AddIconByType</a></code>,
361 <code class="directive"><a href="../mod/mod_autoindex.html#defaulticon">DefaultIcon</a></code>, <code class="directive"><a href="../mod/mod_dir.html#directoryindex">DirectoryIndex</a></code>, <code class="directive"><a href="../mod/mod_autoindex.html#fancyindexing">FancyIndexing</a></code>, <code class="directive"><a href="../mod/mod_autoindex.html#headername">HeaderName</a></code>, <code class="directive"><a href="../mod/mod_autoindex.html#indexignore">IndexIgnore</a></code>, <code class="directive"><a href="../mod/mod_autoindex.html#indexoptions">IndexOptions</a></code>, <code class="directive"><a href="../mod/mod_autoindex.html#readmename">ReadmeName</a></code>,
367 Allow use of the directives controlling host access (<code class="directive"><a href="../mod/mod_authz_host.html#allow">Allow</a></code>, <code class="directive"><a href="../mod/mod_authz_host.html#deny">Deny</a></code> and <code class="directive"><a href="../mod/mod_authz_host.html#order">Order</a></code>).</dd>
372 Allow use of the directives controlling specific directory
373 features (<code class="directive"><a href="#options">Options</a></code> and
374 <code class="directive"><a href="../mod/mod_include.html#xbithack">XBitHack</a></code>).</dd>
379 <div class="example"><p><code>
380 AllowOverride AuthConfig Indexes
385 <li><code class="directive"><a href="#accessfilename">AccessFileName</a></code></li>
386 <li><a href="../configuring.html">Configuration Files</a></li>
387 <li><a href="../howto/htaccess.html">.htaccess Files</a></li>
390 <div class="top"><a href="#page-header"><img alt="top" src="../images/up.gif" /></a></div>
391 <div class="directive-section"><h2><a name="AuthName" id="AuthName">AuthName</a> <a name="authname" id="authname">Directive</a></h2>
392 <table class="directive">
393 <tr><th><a href="directive-dict.html#Description">Description:</a></th><td>Authorization realm for use in HTTP
394 authentication</td></tr>
395 <tr><th><a href="directive-dict.html#Syntax">Syntax:</a></th><td><code>AuthName <var>auth-domain</var></code></td></tr>
396 <tr><th><a href="directive-dict.html#Context">Context:</a></th><td>directory, .htaccess</td></tr>
397 <tr><th><a href="directive-dict.html#Override">Override:</a></th><td>AuthConfig</td></tr>
398 <tr><th><a href="directive-dict.html#Status">Status:</a></th><td>Core</td></tr>
399 <tr><th><a href="directive-dict.html#Module">Module:</a></th><td>core</td></tr>
401 <p>This directive sets the name of the authorization realm for a
402 directory. This realm is given to the client so that the user
403 knows which username and password to send.
404 <code class="directive">AuthName</code> takes a single argument; if the
405 realm name contains spaces, it must be enclosed in quotation
406 marks. It must be accompanied by <code class="directive"><a href="#authtype">AuthType</a></code> and <code class="directive"><a href="#require">Require</a></code> directives, and directives such
407 as <code class="directive"><a href="../mod/mod_authn_file.html#authuserfile">AuthUserFile</a></code> and
408 <code class="directive"><a href="../mod/mod_authz_groupfile.html#authgroupfile">AuthGroupFile</a></code> to
413 <div class="example"><p><code>
414 AuthName "Top Secret"
417 <p>The string provided for the <code>AuthName</code> is what will
418 appear in the password dialog provided by most browsers.</p>
422 <li><a href="../howto/auth.html">Authentication, Authorization, and
423 Access Control</a></li>
426 <div class="top"><a href="#page-header"><img alt="top" src="../images/up.gif" /></a></div>
427 <div class="directive-section"><h2><a name="AuthType" id="AuthType">AuthType</a> <a name="authtype" id="authtype">Directive</a></h2>
428 <table class="directive">
429 <tr><th><a href="directive-dict.html#Description">Description:</a></th><td>Type of user authentication</td></tr>
430 <tr><th><a href="directive-dict.html#Syntax">Syntax:</a></th><td><code>AuthType Basic|Digest</code></td></tr>
431 <tr><th><a href="directive-dict.html#Context">Context:</a></th><td>directory, .htaccess</td></tr>
432 <tr><th><a href="directive-dict.html#Override">Override:</a></th><td>AuthConfig</td></tr>
433 <tr><th><a href="directive-dict.html#Status">Status:</a></th><td>Core</td></tr>
434 <tr><th><a href="directive-dict.html#Module">Module:</a></th><td>core</td></tr>
436 <p>This directive selects the type of user authentication for a
437 directory. Only <code>Basic</code> and <code>Digest</code> are
438 currently implemented.
440 It must be accompanied by <code class="directive"><a href="#authname">AuthName</a></code> and <code class="directive"><a href="#require">Require</a></code> directives, and directives such
441 as <code class="directive"><a href="../mod/mod_authn_file.html#authuserfile">AuthUserFile</a></code> and
442 <code class="directive"><a href="../mod/mod_authz_groupfile.html#authgroupfile">AuthGroupFile</a></code> to
447 <li><a href="../howto/auth.html">Authentication, Authorization,
448 and Access Control</a></li>
451 <div class="top"><a href="#page-header"><img alt="top" src="../images/up.gif" /></a></div>
452 <div class="directive-section"><h2><a name="CGIMapExtension" id="CGIMapExtension">CGIMapExtension</a> <a name="cgimapextension" id="cgimapextension">Directive</a></h2>
453 <table class="directive">
454 <tr><th><a href="directive-dict.html#Description">Description:</a></th><td>Technique for locating the interpreter for CGI
456 <tr><th><a href="directive-dict.html#Syntax">Syntax:</a></th><td><code>CGIMapExtension <var>cgi-path</var> <var>.extension</var></code></td></tr>
457 <tr><th><a href="directive-dict.html#Context">Context:</a></th><td>directory, .htaccess</td></tr>
458 <tr><th><a href="directive-dict.html#Override">Override:</a></th><td>FileInfo</td></tr>
459 <tr><th><a href="directive-dict.html#Status">Status:</a></th><td>Core</td></tr>
460 <tr><th><a href="directive-dict.html#Module">Module:</a></th><td>core</td></tr>
461 <tr><th><a href="directive-dict.html#Compatibility">Compatibility:</a></th><td>NetWare only</td></tr>
463 <p>This directive is used to control how Apache finds the
464 interpreter used to run CGI scripts. For example, setting
465 <code>CGIMapExtension sys:\foo.nlm .foo</code> will
466 cause all CGI script files with a <code>.foo</code> extension to
467 be passed to the FOO interpreter.</p>
470 <div class="top"><a href="#page-header"><img alt="top" src="../images/up.gif" /></a></div>
471 <div class="directive-section"><h2><a name="ContentDigest" id="ContentDigest">ContentDigest</a> <a name="contentdigest" id="contentdigest">Directive</a></h2>
472 <table class="directive">
473 <tr><th><a href="directive-dict.html#Description">Description:</a></th><td>Enables the generation of Content-MD5 HTTP Response
475 <tr><th><a href="directive-dict.html#Syntax">Syntax:</a></th><td><code>ContentDigest On|Off</code></td></tr>
476 <tr><th><a href="directive-dict.html#Default">Default:</a></th><td><code>ContentDigest Off</code></td></tr>
477 <tr><th><a href="directive-dict.html#Context">Context:</a></th><td>server config, virtual host, directory, .htaccess</td></tr>
478 <tr><th><a href="directive-dict.html#Override">Override:</a></th><td>Options</td></tr>
479 <tr><th><a href="directive-dict.html#Status">Status:</a></th><td>Core</td></tr>
480 <tr><th><a href="directive-dict.html#Module">Module:</a></th><td>core</td></tr>
482 <p>This directive enables the generation of
483 <code>Content-MD5</code> headers as defined in RFC1864
484 respectively RFC2068.</p>
486 <p>MD5 is an algorithm for computing a "message digest"
487 (sometimes called "fingerprint") of arbitrary-length data, with
488 a high degree of confidence that any alterations in the data
489 will be reflected in alterations in the message digest.</p>
491 <p>The <code>Content-MD5</code> header provides an end-to-end
492 message integrity check (MIC) of the entity-body. A proxy or
493 client may check this header for detecting accidental
494 modification of the entity-body in transit. Example header:</p>
496 <div class="example"><p><code>
497 Content-MD5: AuLb7Dp1rqtRtxz2m9kRpA==
500 <p>Note that this can cause performance problems on your server
501 since the message digest is computed on every request (the
502 values are not cached).</p>
504 <p><code>Content-MD5</code> is only sent for documents served
505 by the <code class="module"><a href="../mod/core.html">core</a></code>, and not by any module. For example,
506 SSI documents, output from CGI scripts, and byte range responses
507 do not have this header.</p>
510 <div class="top"><a href="#page-header"><img alt="top" src="../images/up.gif" /></a></div>
511 <div class="directive-section"><h2><a name="DefaultType" id="DefaultType">DefaultType</a> <a name="defaulttype" id="defaulttype">Directive</a></h2>
512 <table class="directive">
513 <tr><th><a href="directive-dict.html#Description">Description:</a></th><td>MIME content-type that will be sent if the
514 server cannot determine a type in any other way</td></tr>
515 <tr><th><a href="directive-dict.html#Syntax">Syntax:</a></th><td><code>DefaultType <var>MIME-type</var></code></td></tr>
516 <tr><th><a href="directive-dict.html#Default">Default:</a></th><td><code>DefaultType text/plain</code></td></tr>
517 <tr><th><a href="directive-dict.html#Context">Context:</a></th><td>server config, virtual host, directory, .htaccess</td></tr>
518 <tr><th><a href="directive-dict.html#Override">Override:</a></th><td>FileInfo</td></tr>
519 <tr><th><a href="directive-dict.html#Status">Status:</a></th><td>Core</td></tr>
520 <tr><th><a href="directive-dict.html#Module">Module:</a></th><td>core</td></tr>
522 <p>There will be times when the server is asked to provide a
523 document whose type cannot be determined by its MIME types
526 <p>The server must inform the client of the content-type of the
527 document, so in the event of an unknown type it uses the
528 <code>DefaultType</code>. For example:</p>
530 <div class="example"><p><code>
531 DefaultType image/gif
534 <p>would be appropriate for a directory which contained many GIF
535 images with filenames missing the <code>.gif</code> extension.</p>
537 <p>Note that unlike <code class="directive"><a href="#forcetype">ForceType</a></code>, this directive only
538 provides the default mime-type. All other mime-type definitions,
539 including filename extensions, that might identify the media type
540 will override this default.</p>
543 <div class="top"><a href="#page-header"><img alt="top" src="../images/up.gif" /></a></div>
544 <div class="directive-section"><h2><a name="Directory" id="Directory"><Directory></a> <a name="directory" id="directory">Directive</a></h2>
545 <table class="directive">
546 <tr><th><a href="directive-dict.html#Description">Description:</a></th><td>Enclose a group of directives that apply only to the
547 named file-system directory and sub-directories</td></tr>
548 <tr><th><a href="directive-dict.html#Syntax">Syntax:</a></th><td><code><Directory <var>directory-path</var>>
549 ... </Directory></code></td></tr>
550 <tr><th><a href="directive-dict.html#Context">Context:</a></th><td>server config, virtual host</td></tr>
551 <tr><th><a href="directive-dict.html#Status">Status:</a></th><td>Core</td></tr>
552 <tr><th><a href="directive-dict.html#Module">Module:</a></th><td>core</td></tr>
554 <p><code class="directive"><Directory></code> and
555 <code></Directory></code> are used to enclose a group of
556 directives that will apply only to the named directory and
557 sub-directories of that directory. Any directive that is allowed
558 in a directory context may be used. <var>Directory-path</var> is
559 either the full path to a directory, or a wild-card string using
560 Unix shell-style matching. In a wild-card string, <code>?</code> matches
561 any single character, and <code>*</code> matches any sequences of
562 characters. You may also use <code>[]</code> character ranges. None
563 of the wildcards match a `/' character, so <code><Directory
564 /*/public_html></code> will not match
565 <code>/home/user/public_html</code>, but <code><Directory
566 /home/*/public_html></code> will match. Example:</p>
568 <div class="example"><p><code>
569 <Directory /usr/local/httpd/htdocs><br />
570 <span class="indent">
571 Options Indexes FollowSymLinks<br />
577 <p>Be careful with the <var>directory-path</var> arguments:
578 They have to literally match the filesystem path which Apache uses
579 to access the files. Directives applied to a particular
580 <code><Directory></code> will not apply to files accessed from
581 that same directory via a different path, such as via different symbolic
586 expressions can also be used, with the addition of the
587 <code>~</code> character. For example:</p>
589 <div class="example"><p><code>
590 <Directory ~ "^/www/.*/[0-9]{3}">
593 <p>would match directories in <code>/www/</code> that consisted of
596 <p>If multiple (non-regular expression) <code class="directive"><Directory></code> sections
597 match the directory (or one of its parents) containing a document,
598 then the directives are applied in the order of shortest match
599 first, interspersed with the directives from the <a href="#accessfilename">.htaccess</a> files. For example,
602 <div class="example"><p><code>
603 <Directory /><br />
604 <span class="indent">
605 AllowOverride None<br />
607 </Directory><br />
609 <Directory /home/><br />
610 <span class="indent">
611 AllowOverride FileInfo<br />
616 <p>for access to the document <code>/home/web/dir/doc.html</code>
620 <li>Apply directive <code>AllowOverride None</code>
621 (disabling <code>.htaccess</code> files).</li>
623 <li>Apply directive <code>AllowOverride FileInfo</code> (for
624 directory <code>/home</code>).</li>
626 <li>Apply any <code>FileInfo</code> directives in
627 <code>/home/.htaccess</code>, <code>/home/web/.htaccess</code> and
628 <code>/home/web/dir/.htaccess</code> in that order.</li>
631 <p>Regular expressions are not considered until after all of the
632 normal sections have been applied. Then all of the regular
633 expressions are tested in the order they appeared in the
634 configuration file. For example, with</p>
636 <div class="example"><p><code>
637 <Directory ~ abc$><br />
638 <span class="indent">
639 # ... directives here ...<br />
644 <p>the regular expression section won't be considered until after
645 all normal <code class="directive"><Directory></code>s and
646 <code>.htaccess</code> files have been applied. Then the regular
647 expression will match on <code>/home/abc/public_html/abc</code> and
648 the corresponding <code class="directive"><Directory></code> will
651 <p><strong>Note that the default Apache access for
652 <code><Directory /></code> is <code>Allow from All</code>.
653 This means that Apache will serve any file mapped from an URL. It is
654 recommended that you change this with a block such
657 <div class="example"><p><code>
658 <Directory /><br />
659 <span class="indent">
660 Order Deny,Allow<br />
666 <p><strong>and then override this for directories you
667 <em>want</em> accessible. See the <a href="../misc/security_tips.html">Security Tips</a> page for more
668 details.</strong></p>
670 <p>The directory sections occur in the <code>httpd.conf</code> file.
671 <code class="directive"><Directory></code> directives
672 cannot nest, and cannot appear in a <code class="directive"><a href="#limit"><Limit></a></code> or <code class="directive"><a href="#limitexcept"><LimitExcept></a></code> section.</p>
676 <li><a href="../sections.html">How <Directory>,
677 <Location> and <Files> sections work</a> for an
678 explanation of how these different sections are combined when a
679 request is received</li>
682 <div class="top"><a href="#page-header"><img alt="top" src="../images/up.gif" /></a></div>
683 <div class="directive-section"><h2><a name="DirectoryMatch" id="DirectoryMatch"><DirectoryMatch></a> <a name="directorymatch" id="directorymatch">Directive</a></h2>
684 <table class="directive">
685 <tr><th><a href="directive-dict.html#Description">Description:</a></th><td>Enclose directives that apply to
686 file-system directories matching a regular expression and their
687 subdirectories</td></tr>
688 <tr><th><a href="directive-dict.html#Syntax">Syntax:</a></th><td><code><DirectoryMatch <var>regex</var>>
689 ... </DirectoryMatch></code></td></tr>
690 <tr><th><a href="directive-dict.html#Context">Context:</a></th><td>server config, virtual host</td></tr>
691 <tr><th><a href="directive-dict.html#Status">Status:</a></th><td>Core</td></tr>
692 <tr><th><a href="directive-dict.html#Module">Module:</a></th><td>core</td></tr>
694 <p><code class="directive"><DirectoryMatch></code> and
695 <code></DirectoryMatch></code> are used to enclose a group
696 of directives which will apply only to the named directory and
697 sub-directories of that directory, the same as <code class="directive"><a href="#directory"><Directory></a></code>. However, it
698 takes as an argument a regular expression. For example:</p>
700 <div class="example"><p><code>
701 <DirectoryMatch "^/www/.*/[0-9]{3}">
704 <p>would match directories in <code>/www/</code> that consisted of three
709 <li><code class="directive"><a href="#directory"><Directory></a></code> for
710 a description of how regular expressions are mixed in with normal
711 <code class="directive"><Directory></code>s</li>
712 <li><a href="../sections.html">How <Directory>, <Location> and
713 <Files> sections work</a> for an explanation of how these different
714 sections are combined when a request is received</li>
717 <div class="top"><a href="#page-header"><img alt="top" src="../images/up.gif" /></a></div>
718 <div class="directive-section"><h2><a name="DocumentRoot" id="DocumentRoot">DocumentRoot</a> <a name="documentroot" id="documentroot">Directive</a></h2>
719 <table class="directive">
720 <tr><th><a href="directive-dict.html#Description">Description:</a></th><td>Directory that forms the main document tree visible
721 from the web</td></tr>
722 <tr><th><a href="directive-dict.html#Syntax">Syntax:</a></th><td><code>DocumentRoot <var>directory-path</var></code></td></tr>
723 <tr><th><a href="directive-dict.html#Default">Default:</a></th><td><code>DocumentRoot /usr/local/apache/htdocs</code></td></tr>
724 <tr><th><a href="directive-dict.html#Context">Context:</a></th><td>server config, virtual host</td></tr>
725 <tr><th><a href="directive-dict.html#Status">Status:</a></th><td>Core</td></tr>
726 <tr><th><a href="directive-dict.html#Module">Module:</a></th><td>core</td></tr>
728 <p>This directive sets the directory from which <code>httpd</code>
729 will serve files. Unless matched by a directive like <code class="directive"><a href="../mod/mod_alias.html#alias">Alias</a></code>, the server appends the
730 path from the requested URL to the document root to make the
731 path to the document. Example:</p>
733 <div class="example"><p><code>
734 DocumentRoot /usr/web
738 <code>http://www.my.host.com/index.html</code> refers to
739 <code>/usr/web/index.html</code>.</p>
741 <p>The <code class="directive">DocumentRoot</code> should be specified without
742 a trailing slash.</p>
746 <li><a href="../urlmapping.html">Mapping URLs to Filesystem
750 <div class="top"><a href="#page-header"><img alt="top" src="../images/up.gif" /></a></div>
751 <div class="directive-section"><h2><a name="EnableMMAP" id="EnableMMAP">EnableMMAP</a> <a name="enablemmap" id="enablemmap">Directive</a></h2>
752 <table class="directive">
753 <tr><th><a href="directive-dict.html#Description">Description:</a></th><td>Use memory-mapping to read files during delivery</td></tr>
754 <tr><th><a href="directive-dict.html#Syntax">Syntax:</a></th><td><code>EnableMMAP On|Off</code></td></tr>
755 <tr><th><a href="directive-dict.html#Default">Default:</a></th><td><code>EnableMMAP On</code></td></tr>
756 <tr><th><a href="directive-dict.html#Context">Context:</a></th><td>server config, virtual host, directory, .htaccess</td></tr>
757 <tr><th><a href="directive-dict.html#Override">Override:</a></th><td>FileInfo</td></tr>
758 <tr><th><a href="directive-dict.html#Status">Status:</a></th><td>Core</td></tr>
759 <tr><th><a href="directive-dict.html#Module">Module:</a></th><td>core</td></tr>
761 <p>This directive controls whether the <code>httpd</code> may use
762 memory-mapping if it needs to read the contents of a file during
763 delivery. By default, when the handling of a request requires
764 access to the data within a file -- for example, when delivering a
765 server-parsed file using <code class="module"><a href="../mod/mod_include.html">mod_include</a></code> -- Apache
766 memory-maps the file if the OS supports it.</p>
768 <p>This memory-mapping sometimes yields a performance improvement.
769 But in some environments, it is better to disable the memory-mapping
770 to prevent operational problems:</p>
773 <li>On some multiprocessor systems, memory-mapping can reduce the
774 performance of the <code>httpd</code>.</li>
775 <li>With an NFS-mounted <code class="directive"><a href="#documentroot">DocumentRoot</a></code>,
776 the <code>httpd</code> may crash due to a segmentation fault if a file
777 is deleted or truncated while the <code>httpd</code> has it
781 <p>For server configurations that are vulnerable to these problems,
782 you should disable memory-mapping of delivered files by specifying:</p>
784 <div class="example"><p><code>
788 <p>For NFS mounted files, this feature may be disabled explicitly for
789 the offending files by specifying:</p>
791 <div class="example"><p><code>
792 <Directory "/path-to-nfs-files">
793 <span class="indent">
800 <div class="top"><a href="#page-header"><img alt="top" src="../images/up.gif" /></a></div>
801 <div class="directive-section"><h2><a name="EnableSendfile" id="EnableSendfile">EnableSendfile</a> <a name="enablesendfile" id="enablesendfile">Directive</a></h2>
802 <table class="directive">
803 <tr><th><a href="directive-dict.html#Description">Description:</a></th><td>Use the kernel sendfile support to deliver files to the client</td></tr>
804 <tr><th><a href="directive-dict.html#Syntax">Syntax:</a></th><td><code>EnableSendfile On|Off</code></td></tr>
805 <tr><th><a href="directive-dict.html#Default">Default:</a></th><td><code>EnableSendfile On</code></td></tr>
806 <tr><th><a href="directive-dict.html#Context">Context:</a></th><td>server config, virtual host, directory, .htaccess</td></tr>
807 <tr><th><a href="directive-dict.html#Override">Override:</a></th><td>FileInfo</td></tr>
808 <tr><th><a href="directive-dict.html#Status">Status:</a></th><td>Core</td></tr>
809 <tr><th><a href="directive-dict.html#Module">Module:</a></th><td>core</td></tr>
810 <tr><th><a href="directive-dict.html#Compatibility">Compatibility:</a></th><td>Available in version 2.0.44 and later</td></tr>
812 <p>This directive controls whether <code>httpd</code> may use the sendfile
813 support from the kernel to transmit file contents to the client.
814 By default, when the handling of a request requires no access
815 to the data within a file -- for example, when delivering a
816 static file -- Apache uses sendfile to deliver the file contents
817 without ever reading the file if the OS supports it.</p>
819 <p>This sendfile mechanism avoids seperate read and send operations,
820 and buffer allocations. But on some platforms or within some
821 filesystems, it is better to disable this feature to avoid
822 operational problems:</p>
825 <li>Some platforms may have broken sendfile support that the build
826 system did not detect, especially if the binaries were built on
827 another box and moved to such a machine with broken sendfile
829 <li>With a network-mounted <code class="directive"><a href="#documentroot">DocumentRoot</a></code> (e.g., NFS or SMB),
830 the kernel may be unable to serve the network file through
834 <p>For server configurations that are vulnerable to these problems,
835 you should disable this feature by specifying:</p>
837 <div class="example"><p><code>
841 <p>For NFS or SMB mounted files, this feature may be disabled explicitly
842 for the offending files by specifying:</p>
844 <div class="example"><p><code>
845 <Directory "/path-to-nfs-files">
846 <span class="indent">
853 <div class="top"><a href="#page-header"><img alt="top" src="../images/up.gif" /></a></div>
854 <div class="directive-section"><h2><a name="ErrorDocument" id="ErrorDocument">ErrorDocument</a> <a name="errordocument" id="errordocument">Directive</a></h2>
855 <table class="directive">
856 <tr><th><a href="directive-dict.html#Description">Description:</a></th><td>What the server will return to the client
857 in case of an error</td></tr>
858 <tr><th><a href="directive-dict.html#Syntax">Syntax:</a></th><td><code>ErrorDocument <var>error-code</var> <var>document</var></code></td></tr>
859 <tr><th><a href="directive-dict.html#Context">Context:</a></th><td>server config, virtual host, directory, .htaccess</td></tr>
860 <tr><th><a href="directive-dict.html#Override">Override:</a></th><td>FileInfo</td></tr>
861 <tr><th><a href="directive-dict.html#Status">Status:</a></th><td>Core</td></tr>
862 <tr><th><a href="directive-dict.html#Module">Module:</a></th><td>core</td></tr>
863 <tr><th><a href="directive-dict.html#Compatibility">Compatibility:</a></th><td>Quoting syntax for text messages is different in Apache
866 <p>In the event of a problem or error, Apache can be configured
867 to do one of four things,</p>
870 <li>output a simple hardcoded error message</li>
872 <li>output a customized message</li>
874 <li>redirect to a local <var>URL-path</var> to handle the
877 <li>redirect to an external <var>URL</var> to handle the
881 <p>The first option is the default, while options 2-4 are
882 configured using the <code class="directive">ErrorDocument</code>
883 directive, which is followed by the HTTP response code and a URL
884 or a message. Apache will sometimes offer additional information
885 regarding the problem/error.</p>
887 <p>URLs can begin with a slash (/) for local URLs, or be a full
888 URL which the client can resolve. Alternatively, a message can
889 be provided to be displayed by the browser. Examples:</p>
891 <div class="example"><p><code>
892 ErrorDocument 500 http://foo.example.com/cgi-bin/tester<br />
893 ErrorDocument 404 /cgi-bin/bad_urls.pl<br />
894 ErrorDocument 401 /subscription_info.html<br />
895 ErrorDocument 403 "Sorry can't allow you access today"
898 <p>Note that when you specify an <code class="directive">ErrorDocument</code>
899 that points to a remote URL (ie. anything with a method such as
900 <code>http</code> in front of it), Apache will send a redirect to the
901 client to tell it where to find the document, even if the
902 document ends up being on the same server. This has several
903 implications, the most important being that the client will not
904 receive the original error status code, but instead will
905 receive a redirect status code. This in turn can confuse web
906 robots and other clients which try to determine if a URL is
907 valid using the status code. In addition, if you use a remote
908 URL in an <code>ErrorDocument 401</code>, the client will not
909 know to prompt the user for a password since it will not
910 receive the 401 status code. Therefore, <strong>if you use an
911 <code>ErrorDocument 401</code> directive then it must refer to a local
912 document.</strong></p>
914 <p>Microsoft Internet Explorer (MSIE) will by default ignore
915 server-generated error messages when they are "too small" and substitute
916 its own "friendly" error messages. The size threshold varies depending on
917 the type of error, but in general, if you make your error document
918 greater than 512 bytes, then MSIE will show the server-generated
919 error rather than masking it. More information is available in
920 Microsoft Knowledgebase article <a href="http://support.microsoft.com/default.aspx?scid=kb;en-us;Q294807">Q294807</a>.</p>
922 <p>Prior to version 2.0, messages were indicated by prefixing
923 them with a single unmatched double quote character.</p>
927 <li><a href="../custom-error.html">documentation of
928 customizable responses</a></li>
931 <div class="top"><a href="#page-header"><img alt="top" src="../images/up.gif" /></a></div>
932 <div class="directive-section"><h2><a name="ErrorLog" id="ErrorLog">ErrorLog</a> <a name="errorlog" id="errorlog">Directive</a></h2>
933 <table class="directive">
934 <tr><th><a href="directive-dict.html#Description">Description:</a></th><td>Location where the server will log errors</td></tr>
935 <tr><th><a href="directive-dict.html#Syntax">Syntax:</a></th><td><code> ErrorLog <var>file-path</var>|syslog[:<var>facility</var>]</code></td></tr>
936 <tr><th><a href="directive-dict.html#Default">Default:</a></th><td><code>ErrorLog logs/error_log (Unix)<br />
937 ErrorLog logs/error.log (Windows and OS/2)</code></td></tr>
938 <tr><th><a href="directive-dict.html#Context">Context:</a></th><td>server config, virtual host</td></tr>
939 <tr><th><a href="directive-dict.html#Status">Status:</a></th><td>Core</td></tr>
940 <tr><th><a href="directive-dict.html#Module">Module:</a></th><td>core</td></tr>
942 <p>The <code class="directive">ErrorLog</code> directive sets the name of
943 the file to which the server will log any errors it encounters. If
944 the <var>file-path</var> is not absolute (in general: does not begin
945 with a slash (/)) then it is assumed to be relative to the <code class="directive"><a href="#serverroot">ServerRoot</a></code>.</p>
947 <div class="example"><h3>Example</h3><p><code>
948 ErrorLog /var/log/httpd/error_log
951 <p>If the <var>file-path</var>
952 begins with a pipe (|) then it is assumed to be a command to spawn
953 to handle the error log.</p>
955 <div class="example"><h3>Example</h3><p><code>
956 ErrorLog "|/usr/local/bin/httpd_errors"
959 <p>Using <code>syslog</code> instead of a filename enables logging
960 via syslogd(8) if the system supports it. The default is to use
961 syslog facility <code>local7</code>, but you can override this by
962 using the <code>syslog:<var>facility</var></code> syntax where
963 <var>facility</var> can be one of the names usually documented in
966 <div class="example"><h3>Example</h3><p><code>
970 <p>SECURITY: See the <a href="../misc/security_tips.html#serverroot">security tips</a>
971 document for details on why your security could be compromised
972 if the directory where logfiles are stored is writable by
973 anyone other than the user that starts the server.</p>
974 <div class="warning"><h3>Note</h3>
975 <p>When entering a file path on non-Unix platforms, care should be taken
976 to make sure that only forward slashed are used even though the platform
977 may allow the use of back slashes. In general it is a good idea to always
978 use forward slashes throughout the configuration files.</p>
983 <li><code class="directive"><a href="#loglevel">LogLevel</a></code></li>
984 <li><a href="../logs.html">Apache Log Files</a></li>
987 <div class="top"><a href="#page-header"><img alt="top" src="../images/up.gif" /></a></div>
988 <div class="directive-section"><h2><a name="FileETag" id="FileETag">FileETag</a> <a name="fileetag" id="fileetag">Directive</a></h2>
989 <table class="directive">
990 <tr><th><a href="directive-dict.html#Description">Description:</a></th><td>File attributes used to create the ETag
991 HTTP response header</td></tr>
992 <tr><th><a href="directive-dict.html#Syntax">Syntax:</a></th><td><code>FileETag <var>component</var> ...</code></td></tr>
993 <tr><th><a href="directive-dict.html#Default">Default:</a></th><td><code>FileETag INode MTime Size</code></td></tr>
994 <tr><th><a href="directive-dict.html#Context">Context:</a></th><td>server config, virtual host, directory, .htaccess</td></tr>
995 <tr><th><a href="directive-dict.html#Override">Override:</a></th><td>FileInfo</td></tr>
996 <tr><th><a href="directive-dict.html#Status">Status:</a></th><td>Core</td></tr>
997 <tr><th><a href="directive-dict.html#Module">Module:</a></th><td>core</td></tr>
1000 The <code class="directive">FileETag</code> directive configures the file
1001 attributes that are used to create the <code>ETag</code> (entity
1002 tag) response header field when the document is based on a file.
1003 (The <code>ETag</code> value is used in cache management to save
1004 network bandwidth.) In Apache 1.3.22 and earlier, the
1005 <code>ETag</code> value was <em>always</em> formed
1006 from the file's inode, size, and last-modified time (mtime). The
1007 <code class="directive">FileETag</code> directive allows you to choose
1008 which of these -- if any -- should be used. The recognized keywords are:
1012 <dt><strong>INode</strong></dt>
1013 <dd>The file's i-node number will be included in the calculation</dd>
1014 <dt><strong>MTime</strong></dt>
1015 <dd>The date and time the file was last modified will be included</dd>
1016 <dt><strong>Size</strong></dt>
1017 <dd>The number of bytes in the file will be included</dd>
1018 <dt><strong>All</strong></dt>
1019 <dd>All available fields will be used. This is equivalent to:
1020 <div class="example"><p><code>FileETag INode MTime Size</code></p></div></dd>
1021 <dt><strong>None</strong></dt>
1022 <dd>If a document is file-based, no <code>ETag</code> field will be
1023 included in the response</dd>
1026 <p>The <code>INode</code>, <code>MTime</code>, and <code>Size</code>
1027 keywords may be prefixed with either <code>+</code> or <code>-</code>,
1028 which allow changes to be made to the default setting inherited
1029 from a broader scope. Any keyword appearing without such a prefix
1030 immediately and completely cancels the inherited setting.</p>
1032 <p>If a directory's configuration includes
1033 <code>FileETag INode MTime Size</code>, and a
1034 subdirectory's includes <code>FileETag -INode</code>,
1035 the setting for that subdirectory (which will be inherited by
1036 any sub-subdirectories that don't override it) will be equivalent to
1037 <code>FileETag MTime Size</code>.</p>
1040 <div class="top"><a href="#page-header"><img alt="top" src="../images/up.gif" /></a></div>
1041 <div class="directive-section"><h2><a name="Files" id="Files"><Files></a> <a name="files" id="files">Directive</a></h2>
1042 <table class="directive">
1043 <tr><th><a href="directive-dict.html#Description">Description:</a></th><td>Contains directives that apply to matched
1045 <tr><th><a href="directive-dict.html#Syntax">Syntax:</a></th><td><code><Files <var>filename</var>> ... </Files></code></td></tr>
1046 <tr><th><a href="directive-dict.html#Context">Context:</a></th><td>server config, virtual host, directory, .htaccess</td></tr>
1047 <tr><th><a href="directive-dict.html#Override">Override:</a></th><td>All</td></tr>
1048 <tr><th><a href="directive-dict.html#Status">Status:</a></th><td>Core</td></tr>
1049 <tr><th><a href="directive-dict.html#Module">Module:</a></th><td>core</td></tr>
1051 <p>The <code class="directive"><Files></code> directive
1052 limits the scope of the enclosed directives by filename. It is comparable
1053 to the <code class="directive"><a href="#directory"><Directory></a></code>
1054 and <code class="directive"><a href="#location"><Location></a></code>
1055 directives. It should be matched with a <code></Files></code>
1056 directive. The directives given within this section will be applied to
1057 any object with a basename (last component of filename) matching the
1058 specified filename. <code class="directive"><Files></code>
1059 sections are processed in the order they appear in the
1060 configuration file, after the <code class="directive"><a href="#directory"><Directory></a></code> sections and
1061 <code>.htaccess</code> files are read, but before <code class="directive"><a href="#location"><Location></a></code> sections. Note
1062 that <code class="directive"><Files></code> can be nested
1063 inside <code class="directive"><a href="#directory"><Directory></a></code> sections to restrict the
1064 portion of the filesystem they apply to.</p>
1066 <p>The <var>filename</var> argument should include a filename, or
1067 a wild-card string, where <code>?</code> matches any single character,
1068 and <code>*</code> matches any sequences of characters. Extended regular
1069 expressions can also be used, with the addition of the
1070 <code>~</code> character. For example:</p>
1072 <div class="example"><p><code>
1073 <Files ~ "\.(gif|jpe?g|png)$">
1076 <p>would match most common Internet graphics formats. <code class="directive"><a href="#filesmatch"><FilesMatch></a></code> is preferred,
1079 <p>Note that unlike <code class="directive"><a href="#directory"><Directory></a></code> and <code class="directive"><a href="#location"><Location></a></code> sections, <code class="directive"><Files></code> sections can be used inside
1080 <code>.htaccess</code> files. This allows users to control access to
1081 their own files, at a file-by-file level.</p>
1086 <li><a href="../sections.html">How <Directory>, <Location>
1087 and <Files> sections work</a> for an explanation of how these
1088 different sections are combined when a request is received</li>
1091 <div class="top"><a href="#page-header"><img alt="top" src="../images/up.gif" /></a></div>
1092 <div class="directive-section"><h2><a name="FilesMatch" id="FilesMatch"><FilesMatch></a> <a name="filesmatch" id="filesmatch">Directive</a></h2>
1093 <table class="directive">
1094 <tr><th><a href="directive-dict.html#Description">Description:</a></th><td>Contains directives that apply to regular-expression matched
1096 <tr><th><a href="directive-dict.html#Syntax">Syntax:</a></th><td><code><FilesMatch <var>regex</var>> ... </FilesMatch></code></td></tr>
1097 <tr><th><a href="directive-dict.html#Context">Context:</a></th><td>server config, virtual host, directory, .htaccess</td></tr>
1098 <tr><th><a href="directive-dict.html#Override">Override:</a></th><td>All</td></tr>
1099 <tr><th><a href="directive-dict.html#Status">Status:</a></th><td>Core</td></tr>
1100 <tr><th><a href="directive-dict.html#Module">Module:</a></th><td>core</td></tr>
1102 <p>The <code class="directive"><FilesMatch></code> directive
1103 limits the scope of the enclosed directives by filename, just as the
1104 <code class="directive"><a href="#files"><Files></a></code> directive
1105 does. However, it accepts a regular expression. For example:</p>
1107 <div class="example"><p><code>
1108 <FilesMatch "\.(gif|jpe?g|png)$">
1111 <p>would match most common Internet graphics formats.</p>
1115 <li><a href="../sections.html">How <Directory>, <Location>
1116 and <Files> sections work</a> for an explanation of how these
1117 different sections are combined when a request is received</li>
1120 <div class="top"><a href="#page-header"><img alt="top" src="../images/up.gif" /></a></div>
1121 <div class="directive-section"><h2><a name="ForceType" id="ForceType">ForceType</a> <a name="forcetype" id="forcetype">Directive</a></h2>
1122 <table class="directive">
1123 <tr><th><a href="directive-dict.html#Description">Description:</a></th><td>Forces all matching files to be served with the specified
1124 MIME content-type</td></tr>
1125 <tr><th><a href="directive-dict.html#Syntax">Syntax:</a></th><td><code>ForceType <var>MIME-type</var>|None</code></td></tr>
1126 <tr><th><a href="directive-dict.html#Context">Context:</a></th><td>directory, .htaccess</td></tr>
1127 <tr><th><a href="directive-dict.html#Override">Override:</a></th><td>FileInfo</td></tr>
1128 <tr><th><a href="directive-dict.html#Status">Status:</a></th><td>Core</td></tr>
1129 <tr><th><a href="directive-dict.html#Module">Module:</a></th><td>core</td></tr>
1130 <tr><th><a href="directive-dict.html#Compatibility">Compatibility:</a></th><td>Moved to the core in Apache 2.0</td></tr>
1132 <p>When placed into an <code>.htaccess</code> file or a
1133 <code class="directive"><a href="#directory"><Directory></a></code>, or
1134 <code class="directive"><a href="#location"><Location></a></code> or
1135 <code class="directive"><a href="#files"><Files></a></code>
1136 section, this directive forces all matching files to be served
1137 with the content type identification given by
1138 <var>MIME-type</var>. For example, if you had a directory full of
1139 GIF files, but did not want to label them all with <code>.gif</code>,
1140 you might want to use:</p>
1142 <div class="example"><p><code>
1146 <p>Note that unlike <code class="directive"><a href="#defaulttype">DefaultType</a></code>,
1147 this directive overrides all mime-type associations, including
1148 filename extensions, that might identify the media type.</p>
1150 <p>You can override any <code class="directive">ForceType</code> setting
1151 by using the value of <code>None</code>:</p>
1153 <div class="example"><p><code>
1154 # force all files to be image/gif:<br />
1155 <Location /images><br />
1156 <span class="indent">
1157 ForceType image/gif<br />
1159 </Location><br />
1161 # but normal mime-type associations here:<br />
1162 <Location /images/mixed><br />
1163 <span class="indent">
1164 ForceType None<br />
1170 <div class="top"><a href="#page-header"><img alt="top" src="../images/up.gif" /></a></div>
1171 <div class="directive-section"><h2><a name="HostnameLookups" id="HostnameLookups">HostnameLookups</a> <a name="hostnamelookups" id="hostnamelookups">Directive</a></h2>
1172 <table class="directive">
1173 <tr><th><a href="directive-dict.html#Description">Description:</a></th><td>Enables DNS lookups on client IP addresses</td></tr>
1174 <tr><th><a href="directive-dict.html#Syntax">Syntax:</a></th><td><code>HostnameLookups On|Off|Double</code></td></tr>
1175 <tr><th><a href="directive-dict.html#Default">Default:</a></th><td><code>HostnameLookups Off</code></td></tr>
1176 <tr><th><a href="directive-dict.html#Context">Context:</a></th><td>server config, virtual host, directory</td></tr>
1177 <tr><th><a href="directive-dict.html#Status">Status:</a></th><td>Core</td></tr>
1178 <tr><th><a href="directive-dict.html#Module">Module:</a></th><td>core</td></tr>
1180 <p>This directive enables DNS lookups so that host names can be
1181 logged (and passed to CGIs/SSIs in <code>REMOTE_HOST</code>).
1182 The value <code>Double</code> refers to doing double-reverse
1183 DNS lookup. That is, after a reverse lookup is performed, a forward
1184 lookup is then performed on that result. At least one of the ip
1185 addresses in the forward lookup must match the original
1186 address. (In "tcpwrappers" terminology this is called
1187 <code>PARANOID</code>.)</p>
1189 <p>Regardless of the setting, when <code class="module"><a href="../mod/mod_authz_host.html">mod_authz_host</a></code> is
1190 used for controlling access by hostname, a double reverse lookup
1191 will be performed. This is necessary for security. Note that the
1192 result of this double-reverse isn't generally available unless you
1193 set <code>HostnameLookups Double</code>. For example, if only
1194 <code>HostnameLookups On</code> and a request is made to an object
1195 that is protected by hostname restrictions, regardless of whether
1196 the double-reverse fails or not, CGIs will still be passed the
1197 single-reverse result in <code>REMOTE_HOST</code>.</p>
1199 <p>The default is <code>Off</code> in order to save the network
1200 traffic for those sites that don't truly need the reverse
1201 lookups done. It is also better for the end users because they
1202 don't have to suffer the extra latency that a lookup entails.
1203 Heavily loaded sites should leave this directive
1204 <code>Off</code>, since DNS lookups can take considerable
1205 amounts of time. The utility <a href="../programs/logresolve.html">logresolve</a>, compiled by default
1206 to the <code>bin</code> subdirectory of your installation directory, can
1207 be used to look up host names from logged IP addresses offline.</p>
1210 <div class="top"><a href="#page-header"><img alt="top" src="../images/up.gif" /></a></div>
1211 <div class="directive-section"><h2><a name="IfDefine" id="IfDefine"><IfDefine></a> <a name="ifdefine" id="ifdefine">Directive</a></h2>
1212 <table class="directive">
1213 <tr><th><a href="directive-dict.html#Description">Description:</a></th><td>Encloses directives that will be processed only
1214 if a test is true at startup</td></tr>
1215 <tr><th><a href="directive-dict.html#Syntax">Syntax:</a></th><td><code><IfDefine [!]<var>parameter-name</var>> ...
1216 </IfDefine></code></td></tr>
1217 <tr><th><a href="directive-dict.html#Context">Context:</a></th><td>server config, virtual host, directory, .htaccess</td></tr>
1218 <tr><th><a href="directive-dict.html#Override">Override:</a></th><td>All</td></tr>
1219 <tr><th><a href="directive-dict.html#Status">Status:</a></th><td>Core</td></tr>
1220 <tr><th><a href="directive-dict.html#Module">Module:</a></th><td>core</td></tr>
1222 <p>The <code><IfDefine <var>test</var>>...</IfDefine>
1223 </code> section is used to mark directives that are conditional. The
1224 directives within an <code class="directive"><IfDefine></code>
1225 section are only processed if the <var>test</var> is true. If <var>
1226 test</var> is false, everything between the start and end markers is
1229 <p>The <var>test</var> in the <code class="directive"><IfDefine></code> section directive can be one of two forms:</p>
1232 <li><var>parameter-name</var></li>
1234 <li><code>!</code><var>parameter-name</var></li>
1237 <p>In the former case, the directives between the start and end
1238 markers are only processed if the parameter named
1239 <var>parameter-name</var> is defined. The second format reverses
1240 the test, and only processes the directives if
1241 <var>parameter-name</var> is <strong>not</strong> defined.</p>
1243 <p>The <var>parameter-name</var> argument is a define as given on
1244 the <code>httpd</code> command line via <code>-D<var>parameter-</var>
1245 </code>, at the time the server was started.</p>
1247 <p><code class="directive"><IfDefine></code> sections are
1248 nest-able, which can be used to implement simple
1249 multiple-parameter tests. Example:</p>
1251 <div class="example"><p><code>
1252 httpd -DReverseProxy ...<br />
1255 <IfDefine ReverseProxy><br />
1256 <span class="indent">
1257 LoadModule rewrite_module modules/mod_rewrite.so<br />
1258 LoadModule proxy_module modules/libproxy.so<br />
1264 <div class="top"><a href="#page-header"><img alt="top" src="../images/up.gif" /></a></div>
1265 <div class="directive-section"><h2><a name="IfModule" id="IfModule"><IfModule></a> <a name="ifmodule" id="ifmodule">Directive</a></h2>
1266 <table class="directive">
1267 <tr><th><a href="directive-dict.html#Description">Description:</a></th><td>Encloses directives that are processed conditional on the
1268 presence or absence of a specific module</td></tr>
1269 <tr><th><a href="directive-dict.html#Syntax">Syntax:</a></th><td><code><IfModule [!]<var>module-name</var>> ...
1270 </IfModule></code></td></tr>
1271 <tr><th><a href="directive-dict.html#Context">Context:</a></th><td>server config, virtual host, directory, .htaccess</td></tr>
1272 <tr><th><a href="directive-dict.html#Override">Override:</a></th><td>All</td></tr>
1273 <tr><th><a href="directive-dict.html#Status">Status:</a></th><td>Core</td></tr>
1274 <tr><th><a href="directive-dict.html#Module">Module:</a></th><td>core</td></tr>
1276 <p>The <code><IfModule <var>test</var>>...</IfModule></code>
1277 section is used to mark directives that are conditional on the presence of
1278 a specific module. The directives within an <code class="directive"><IfModule></code> section are only processed if the <var>test</var>
1279 is true. If <var>test</var> is false, everything between the start and
1280 end markers is ignored.</p>
1282 <p>The <var>test</var> in the <code class="directive"><IfModule></code> section directive can be one of two forms:</p>
1285 <li><var>module name</var></li>
1287 <li>!<var>module name</var></li>
1290 <p>In the former case, the directives between the start and end
1291 markers are only processed if the module named <var>module
1292 name</var> is included in Apache -- either compiled in or
1293 dynamically loaded using <code class="directive"><a href="../mod/mod_so.html#loadmodule">LoadModule</a></code>. The second format reverses the test,
1294 and only processes the directives if <var>module name</var> is
1295 <strong>not</strong> included.</p>
1297 <p>The <var>module name</var> argument is the file name of the
1298 module, at the time it was compiled. For example,
1299 <code>mod_rewrite.c</code>. If a module consists of several
1300 source files, use the name of the file containing the string
1301 <code>STANDARD20_MODULE_STUFF</code>.</p>
1303 <p><code class="directive"><IfModule></code> sections are
1304 nest-able, which can be used to implement simple multiple-module
1307 <div class="note">This section should only be used if you need to have one
1308 configuration file that works whether or not a specific module
1309 is available. In normal operation, directives need not be
1310 placed in <code class="directive"><IfModule></code>
1314 <div class="top"><a href="#page-header"><img alt="top" src="../images/up.gif" /></a></div>
1315 <div class="directive-section"><h2><a name="Include" id="Include">Include</a> <a name="include" id="include">Directive</a></h2>
1316 <table class="directive">
1317 <tr><th><a href="directive-dict.html#Description">Description:</a></th><td>Includes other configuration files from within
1318 the server configuration files</td></tr>
1319 <tr><th><a href="directive-dict.html#Syntax">Syntax:</a></th><td><code>Include <var>file-path</var>|<var>directory-path</var></code></td></tr>
1320 <tr><th><a href="directive-dict.html#Context">Context:</a></th><td>server config, virtual host, directory</td></tr>
1321 <tr><th><a href="directive-dict.html#Status">Status:</a></th><td>Core</td></tr>
1322 <tr><th><a href="directive-dict.html#Module">Module:</a></th><td>core</td></tr>
1323 <tr><th><a href="directive-dict.html#Compatibility">Compatibility:</a></th><td>Wildcard matching available in 2.0.41 and later</td></tr>
1325 <p>This directive allows inclusion of other configuration files
1326 from within the server configuration files.</p>
1328 <p>Shell-style (<code>fnmatch()</code>) wildcard characters can be used to
1329 include several files at once, in alphabetical order. In
1330 addition, if <code class="directive">Include</code> points to a directory,
1331 rather than a file, Apache will read all files in that directory
1332 and any subdirectory. But including entire directories is not
1333 recommended, because it is easy to accidentally leave temporary
1334 files in a directory that can cause <code>httpd</code> to
1337 <p>The file path specified may be an absolute path (i.e.
1338 starting with a slash), or may be relative to the
1339 <code class="directive"><a href="#serverroot">ServerRoot</a></code> directory.</p>
1343 <div class="example"><p><code>
1344 Include /usr/local/apache2/conf/ssl.conf<br />
1345 Include /usr/local/apache2/conf/vhosts/*.conf
1348 <p>Or, providing paths relative to your <code class="directive"><a href="#serverroot">ServerRoot</a></code> directory:</p>
1350 <div class="example"><p><code>
1351 Include conf/ssl.conf<br />
1352 Include conf/vhosts/*.conf
1355 <p>Running <code>apachectl configtest</code> will give you a list
1356 of the files that are being processed during the configuration
1359 <div class="example"><p><code>
1360 root@host# apachectl configtest<br />
1361 Processing config file: /usr/local/apache2/conf/ssl.conf<br />
1362 Processing config file: /usr/local/apache2/conf/vhosts/vhost1.conf<br />
1363 Processing config file: /usr/local/apache2/conf/vhosts/vhost2.conf<br />
1369 <li><a href="../programs/apachectl.html">apachectl</a></li>
1372 <div class="top"><a href="#page-header"><img alt="top" src="../images/up.gif" /></a></div>
1373 <div class="directive-section"><h2><a name="KeepAlive" id="KeepAlive">KeepAlive</a> <a name="keepalive" id="keepalive">Directive</a></h2>
1374 <table class="directive">
1375 <tr><th><a href="directive-dict.html#Description">Description:</a></th><td>Enables HTTP persistent connections</td></tr>
1376 <tr><th><a href="directive-dict.html#Syntax">Syntax:</a></th><td><code>KeepAlive On|Off</code></td></tr>
1377 <tr><th><a href="directive-dict.html#Default">Default:</a></th><td><code>KeepAlive On</code></td></tr>
1378 <tr><th><a href="directive-dict.html#Context">Context:</a></th><td>server config, virtual host</td></tr>
1379 <tr><th><a href="directive-dict.html#Status">Status:</a></th><td>Core</td></tr>
1380 <tr><th><a href="directive-dict.html#Module">Module:</a></th><td>core</td></tr>
1382 <p>The Keep-Alive extension to HTTP/1.0 and the persistent
1383 connection feature of HTTP/1.1 provide long-lived HTTP sessions
1384 which allow multiple requests to be sent over the same TCP
1385 connection. In some cases this has been shown to result in an
1386 almost 50% speedup in latency times for HTML documents with
1387 many images. To enable Keep-Alive connections, set
1388 <code>KeepAlive On</code>.</p>
1390 <p>For HTTP/1.0 clients, Keep-Alive connections will only be
1391 used if they are specifically requested by a client. In
1392 addition, a Keep-Alive connection with an HTTP/1.0 client can
1393 only be used when the length of the content is known in
1394 advance. This implies that dynamic content such as CGI output,
1395 SSI pages, and server-generated directory listings will
1396 generally not use Keep-Alive connections to HTTP/1.0 clients.
1397 For HTTP/1.1 clients, persistent connections are the default
1398 unless otherwise specified. If the client requests it, chunked
1399 encoding will be used in order to send content of unknown
1400 length over persistent connections.</p>
1404 <li><code class="directive"><a href="#maxkeepaliverequests">MaxKeepAliveRequests</a></code></li>
1407 <div class="top"><a href="#page-header"><img alt="top" src="../images/up.gif" /></a></div>
1408 <div class="directive-section"><h2><a name="KeepAliveTimeout" id="KeepAliveTimeout">KeepAliveTimeout</a> <a name="keepalivetimeout" id="keepalivetimeout">Directive</a></h2>
1409 <table class="directive">
1410 <tr><th><a href="directive-dict.html#Description">Description:</a></th><td>Amount of time the server will wait for subsequent
1411 requests on a persistent connection</td></tr>
1412 <tr><th><a href="directive-dict.html#Syntax">Syntax:</a></th><td><code>KeepAliveTimeout <var>seconds</var></code></td></tr>
1413 <tr><th><a href="directive-dict.html#Default">Default:</a></th><td><code>KeepAliveTimeout 15</code></td></tr>
1414 <tr><th><a href="directive-dict.html#Context">Context:</a></th><td>server config, virtual host</td></tr>
1415 <tr><th><a href="directive-dict.html#Status">Status:</a></th><td>Core</td></tr>
1416 <tr><th><a href="directive-dict.html#Module">Module:</a></th><td>core</td></tr>
1418 <p>The number of seconds Apache will wait for a subsequent
1419 request before closing the connection. Once a request has been
1420 received, the timeout value specified by the
1421 <code class="directive"><a href="#timeout">Timeout</a></code> directive applies.</p>
1423 <p>Setting <code class="directive">KeepAliveTimeout</code> to a high value
1424 may cause performance problems in heavily loaded servers. The
1425 higher the timeout, the more server processes will be kept
1426 occupied waiting on connections with idle clients.</p>
1429 <div class="top"><a href="#page-header"><img alt="top" src="../images/up.gif" /></a></div>
1430 <div class="directive-section"><h2><a name="Limit" id="Limit"><Limit></a> <a name="limit" id="limit">Directive</a></h2>
1431 <table class="directive">
1432 <tr><th><a href="directive-dict.html#Description">Description:</a></th><td>Restrict enclosed access controls to only certain HTTP
1434 <tr><th><a href="directive-dict.html#Syntax">Syntax:</a></th><td><code><Limit <var>method</var> [<var>method</var>] ... > ...
1435 </Limit></code></td></tr>
1436 <tr><th><a href="directive-dict.html#Context">Context:</a></th><td>server config, virtual host, directory, .htaccess</td></tr>
1437 <tr><th><a href="directive-dict.html#Override">Override:</a></th><td>All</td></tr>
1438 <tr><th><a href="directive-dict.html#Status">Status:</a></th><td>Core</td></tr>
1439 <tr><th><a href="directive-dict.html#Module">Module:</a></th><td>core</td></tr>
1441 <p>Access controls are normally effective for
1442 <strong>all</strong> access methods, and this is the usual
1443 desired behavior. <strong>In the general case, access control
1444 directives should not be placed within a
1445 <code class="directive"><Limit></code> section.</strong></p>
1447 <p>The purpose of the <code class="directive"><Limit></code>
1448 directive is to restrict the effect of the access controls to the
1449 nominated HTTP methods. For all other methods, the access
1450 restrictions that are enclosed in the <code class="directive"><Limit></code> bracket <strong>will have no
1451 effect</strong>. The following example applies the access control
1452 only to the methods <code>POST</code>, <code>PUT</code>, and
1453 <code>DELETE</code>, leaving all other methods unprotected:</p>
1455 <div class="example"><p><code>
1456 <Limit POST PUT DELETE><br />
1457 <span class="indent">
1458 Require valid-user<br />
1463 <p>The method names listed can be one or more of: <code>GET</code>,
1464 <code>POST</code>, <code>PUT</code>, <code>DELETE</code>,
1465 <code>CONNECT</code>, <code>OPTIONS</code>,
1466 <code>PATCH</code>, <code>PROPFIND</code>, <code>PROPPATCH</code>,
1467 <code>MKCOL</code>, <code>COPY</code>, <code>MOVE</code>,
1468 <code>LOCK</code>, and <code>UNLOCK</code>. <strong>The method name is
1469 case-sensitive.</strong> If <code>GET</code> is used it will also
1470 restrict <code>HEAD</code> requests. The <code>TRACE</code> method
1471 cannot be limited.</p>
1474 <div class="top"><a href="#page-header"><img alt="top" src="../images/up.gif" /></a></div>
1475 <div class="directive-section"><h2><a name="LimitExcept" id="LimitExcept"><LimitExcept></a> <a name="limitexcept" id="limitexcept">Directive</a></h2>
1476 <table class="directive">
1477 <tr><th><a href="directive-dict.html#Description">Description:</a></th><td>Restrict access controls to all HTTP methods
1478 except the named ones</td></tr>
1479 <tr><th><a href="directive-dict.html#Syntax">Syntax:</a></th><td><code><LimitExcept <var>method</var> [<var>method</var>] ... > ...
1480 </LimitExcept></code></td></tr>
1481 <tr><th><a href="directive-dict.html#Context">Context:</a></th><td>server config, virtual host, directory, .htaccess</td></tr>
1482 <tr><th><a href="directive-dict.html#Override">Override:</a></th><td>All</td></tr>
1483 <tr><th><a href="directive-dict.html#Status">Status:</a></th><td>Core</td></tr>
1484 <tr><th><a href="directive-dict.html#Module">Module:</a></th><td>core</td></tr>
1486 <p><code class="directive"><LimitExcept></code> and
1487 <code></LimitExcept></code> are used to enclose
1488 a group of access control directives which will then apply to any
1489 HTTP access method <strong>not</strong> listed in the arguments;
1490 i.e., it is the opposite of a <code class="directive"><a href="#limit"><Limit></a></code> section and can be used to control
1491 both standard and nonstandard/unrecognized methods. See the
1492 documentation for <code class="directive"><a href="#limit"><Limit></a></code> for more details.</p>
1496 <div class="example"><p><code>
1497 <LimitExcept POST GET><br />
1498 <span class="indent">
1499 Require valid-user<br />
1506 <div class="top"><a href="#page-header"><img alt="top" src="../images/up.gif" /></a></div>
1507 <div class="directive-section"><h2><a name="LimitRequestBody" id="LimitRequestBody">LimitRequestBody</a> <a name="limitrequestbody" id="limitrequestbody">Directive</a></h2>
1508 <table class="directive">
1509 <tr><th><a href="directive-dict.html#Description">Description:</a></th><td>Restricts the total size of the HTTP request body sent
1510 from the client</td></tr>
1511 <tr><th><a href="directive-dict.html#Syntax">Syntax:</a></th><td><code>LimitRequestBody <var>bytes</var></code></td></tr>
1512 <tr><th><a href="directive-dict.html#Default">Default:</a></th><td><code>LimitRequestBody 0</code></td></tr>
1513 <tr><th><a href="directive-dict.html#Context">Context:</a></th><td>server config, virtual host, directory, .htaccess</td></tr>
1514 <tr><th><a href="directive-dict.html#Override">Override:</a></th><td>All</td></tr>
1515 <tr><th><a href="directive-dict.html#Status">Status:</a></th><td>Core</td></tr>
1516 <tr><th><a href="directive-dict.html#Module">Module:</a></th><td>core</td></tr>
1518 <p>This directive specifies the number of <var>bytes</var> from 0
1519 (meaning unlimited) to 2147483647 (2GB) that are allowed in a
1520 request body. The default value is defined by the compile-time
1521 constant <code>DEFAULT_LIMIT_REQUEST_BODY</code> (0 as
1524 <p>The <code class="directive">LimitRequestBody</code> directive allows
1525 the user to set a limit on the allowed size of an HTTP request
1526 message body within the context in which the directive is given
1527 (server, per-directory, per-file or per-location). If the client
1528 request exceeds that limit, the server will return an error
1529 response instead of servicing the request. The size of a normal
1530 request message body will vary greatly depending on the nature of
1531 the resource and the methods allowed on that resource. CGI scripts
1532 typically use the message body for retrieving form information.
1533 Implementations of the <code>PUT</code> method will require
1534 a value at least as large as any representation that the server
1535 wishes to accept for that resource.</p>
1537 <p>This directive gives the server administrator greater
1538 control over abnormal client request behavior, which may be
1539 useful for avoiding some forms of denial-of-service
1542 <p>If, for example, you are permitting file upload to a particular
1543 location, and wish to limit the size of the uploaded file to 100K,
1544 you might use the following directive:</p>
1546 <div class="example"><p><code>
1547 LimitRequestBody 102400
1552 <div class="top"><a href="#page-header"><img alt="top" src="../images/up.gif" /></a></div>
1553 <div class="directive-section"><h2><a name="LimitRequestFields" id="LimitRequestFields">LimitRequestFields</a> <a name="limitrequestfields" id="limitrequestfields">Directive</a></h2>
1554 <table class="directive">
1555 <tr><th><a href="directive-dict.html#Description">Description:</a></th><td>Limits the number of HTTP request header fields that
1556 will be accepted from the client</td></tr>
1557 <tr><th><a href="directive-dict.html#Syntax">Syntax:</a></th><td><code>LimitRequestFields <var>number</var></code></td></tr>
1558 <tr><th><a href="directive-dict.html#Default">Default:</a></th><td><code>LimitRequestFields 100</code></td></tr>
1559 <tr><th><a href="directive-dict.html#Context">Context:</a></th><td>server config</td></tr>
1560 <tr><th><a href="directive-dict.html#Status">Status:</a></th><td>Core</td></tr>
1561 <tr><th><a href="directive-dict.html#Module">Module:</a></th><td>core</td></tr>
1563 <p><var>Number</var> is an integer from 0 (meaning unlimited) to
1564 32767. The default value is defined by the compile-time
1565 constant <code>DEFAULT_LIMIT_REQUEST_FIELDS</code> (100 as
1568 <p>The <code class="directive">LimitRequestFields</code> directive allows
1569 the server administrator to modify the limit on the number of
1570 request header fields allowed in an HTTP request. A server needs
1571 this value to be larger than the number of fields that a normal
1572 client request might include. The number of request header fields
1573 used by a client rarely exceeds 20, but this may vary among
1574 different client implementations, often depending upon the extent
1575 to which a user has configured their browser to support detailed
1576 content negotiation. Optional HTTP extensions are often expressed
1577 using request header fields.</p>
1579 <p>This directive gives the server administrator greater
1580 control over abnormal client request behavior, which may be
1581 useful for avoiding some forms of denial-of-service attacks.
1582 The value should be increased if normal clients see an error
1583 response from the server that indicates too many fields were
1584 sent in the request.</p>
1588 <div class="example"><p><code>
1589 LimitRequestFields 50
1594 <div class="top"><a href="#page-header"><img alt="top" src="../images/up.gif" /></a></div>
1595 <div class="directive-section"><h2><a name="LimitRequestFieldSize" id="LimitRequestFieldSize">LimitRequestFieldSize</a> <a name="limitrequestfieldsize" id="limitrequestfieldsize">Directive</a></h2>
1596 <table class="directive">
1597 <tr><th><a href="directive-dict.html#Description">Description:</a></th><td>Limits the size of the HTTP request header allowed from the
1599 <tr><th><a href="directive-dict.html#Syntax">Syntax:</a></th><td><code>LimitRequestFieldsize <var>bytes</var></code></td></tr>
1600 <tr><th><a href="directive-dict.html#Default">Default:</a></th><td><code>LimitRequestFieldsize 8190</code></td></tr>
1601 <tr><th><a href="directive-dict.html#Context">Context:</a></th><td>server config</td></tr>
1602 <tr><th><a href="directive-dict.html#Status">Status:</a></th><td>Core</td></tr>
1603 <tr><th><a href="directive-dict.html#Module">Module:</a></th><td>core</td></tr>
1605 <p>This directive specifies the number of <var>bytes</var> from 0
1606 to the value of the compile-time constant
1607 <code>DEFAULT_LIMIT_REQUEST_FIELDSIZE</code> (8190 as
1608 distributed) that will be allowed in an HTTP request
1611 <p>The <code class="directive">LimitRequestFieldSize</code> directive
1612 allows the server administrator to reduce the limit on the allowed
1613 size of an HTTP request header field below the normal input buffer
1614 size compiled with the server. A server needs this value to be
1615 large enough to hold any one header field from a normal client
1616 request. The size of a normal request header field will vary
1617 greatly among different client implementations, often depending
1618 upon the extent to which a user has configured their browser to
1619 support detailed content negotiation.</p>
1621 <p>This directive gives the server administrator greater
1622 control over abnormal client request behavior, which may be
1623 useful for avoiding some forms of denial-of-service attacks.</p>
1627 <div class="example"><p><code>
1628 LimitRequestFieldSize 4094
1631 <div class="note">Under normal conditions, the value should not be changed from
1636 <div class="top"><a href="#page-header"><img alt="top" src="../images/up.gif" /></a></div>
1637 <div class="directive-section"><h2><a name="LimitRequestLine" id="LimitRequestLine">LimitRequestLine</a> <a name="limitrequestline" id="limitrequestline">Directive</a></h2>
1638 <table class="directive">
1639 <tr><th><a href="directive-dict.html#Description">Description:</a></th><td>Limit the size of the HTTP request line that will be accepted
1640 from the client</td></tr>
1641 <tr><th><a href="directive-dict.html#Syntax">Syntax:</a></th><td><code>LimitRequestLine <var>bytes</var></code></td></tr>
1642 <tr><th><a href="directive-dict.html#Default">Default:</a></th><td><code>LimitRequestLine 8190</code></td></tr>
1643 <tr><th><a href="directive-dict.html#Context">Context:</a></th><td>server config</td></tr>
1644 <tr><th><a href="directive-dict.html#Status">Status:</a></th><td>Core</td></tr>
1645 <tr><th><a href="directive-dict.html#Module">Module:</a></th><td>core</td></tr>
1647 <p>This directive sets the number of <var>bytes</var> from 0 to
1648 the value of the compile-time constant
1649 <code>DEFAULT_LIMIT_REQUEST_LINE</code> (8190 as distributed)
1650 that will be allowed on the HTTP request-line.</p>
1652 <p>The <code class="directive">LimitRequestLine</code> directive allows
1653 the server administrator to reduce the limit on the allowed size
1654 of a client's HTTP request-line below the normal input buffer size
1655 compiled with the server. Since the request-line consists of the
1656 HTTP method, URI, and protocol version, the
1657 <code class="directive">LimitRequestLine</code> directive places a
1658 restriction on the length of a request-URI allowed for a request
1659 on the server. A server needs this value to be large enough to
1660 hold any of its resource names, including any information that
1661 might be passed in the query part of a <code>GET</code> request.</p>
1663 <p>This directive gives the server administrator greater
1664 control over abnormal client request behavior, which may be
1665 useful for avoiding some forms of denial-of-service attacks.</p>
1669 <div class="example"><p><code>
1670 LimitRequestLine 4094
1673 <div class="note">Under normal conditions, the value should not be changed from
1677 <div class="top"><a href="#page-header"><img alt="top" src="../images/up.gif" /></a></div>
1678 <div class="directive-section"><h2><a name="LimitXMLRequestBody" id="LimitXMLRequestBody">LimitXMLRequestBody</a> <a name="limitxmlrequestbody" id="limitxmlrequestbody">Directive</a></h2>
1679 <table class="directive">
1680 <tr><th><a href="directive-dict.html#Description">Description:</a></th><td>Limits the size of an XML-based request body</td></tr>
1681 <tr><th><a href="directive-dict.html#Syntax">Syntax:</a></th><td><code>LimitXMLRequestBody <var>bytes</var></code></td></tr>
1682 <tr><th><a href="directive-dict.html#Default">Default:</a></th><td><code>LimitXMLRequestBody 1000000</code></td></tr>
1683 <tr><th><a href="directive-dict.html#Context">Context:</a></th><td>server config, virtual host, directory, .htaccess</td></tr>
1684 <tr><th><a href="directive-dict.html#Override">Override:</a></th><td>All</td></tr>
1685 <tr><th><a href="directive-dict.html#Status">Status:</a></th><td>Core</td></tr>
1686 <tr><th><a href="directive-dict.html#Module">Module:</a></th><td>core</td></tr>
1688 <p>Limit (in bytes) on maximum size of an XML-based request
1689 body. A value of <code>0</code> will disable any checking.</p>
1693 <div class="example"><p><code>
1694 LimitXMLRequestBody 0
1699 <div class="top"><a href="#page-header"><img alt="top" src="../images/up.gif" /></a></div>
1700 <div class="directive-section"><h2><a name="Location" id="Location"><Location></a> <a name="location" id="location">Directive</a></h2>
1701 <table class="directive">
1702 <tr><th><a href="directive-dict.html#Description">Description:</a></th><td>Applies the enclosed directives only to matching
1704 <tr><th><a href="directive-dict.html#Syntax">Syntax:</a></th><td><code><Location
1705 <var>URL-path</var>|<var>URL</var>> ... </Location></code></td></tr>
1706 <tr><th><a href="directive-dict.html#Context">Context:</a></th><td>server config, virtual host</td></tr>
1707 <tr><th><a href="directive-dict.html#Status">Status:</a></th><td>Core</td></tr>
1708 <tr><th><a href="directive-dict.html#Module">Module:</a></th><td>core</td></tr>
1710 <p>The <code class="directive"><Location></code> directive
1711 limits the scope of the enclosed directives by URL. It is similar to the
1712 <code class="directive"><a href="#directory"><Directory></a></code>
1713 directive, and starts a subsection which is terminated with a
1714 <code></Location></code> directive. <code class="directive"><Location></code> sections are processed in the
1715 order they appear in the configuration file, after the <code class="directive"><a href="#directory"><Directory></a></code> sections and
1716 <code>.htaccess</code> files are read, and after the <code class="directive"><a href="#files"><Files></a></code> sections.</p>
1718 <p><code class="directive"><Location></code> sections operate
1719 completely outside the filesystem. This has several consequences.
1720 Most importantly, <code class="directive"><Location></code>
1721 directives should not be used to control access to filesystem
1722 locations. Since several different URLs may map to the same
1723 filesystem location, such access controls may by circumvented.</p>
1725 <div class="note"><h3>When to use <code class="directive"><Location></code></h3>
1727 <p>Use <code class="directive"><Location></code> to apply
1728 directives to content that lives outside the filesystem. For
1729 content that lives in the filesystem, use <code class="directive"><a href="#directory"><Directory></a></code> and <code class="directive"><a href="#files"><Files></a></code>. An exception is
1730 <code><Location /></code>, which is an easy way to
1731 apply a configuration to the entire server.</p>
1734 <p>For all origin (non-proxy) requests, the URL to be matched is a
1735 URL-path of the form <code>/path/</code>. No scheme, hostname,
1736 port, or query string may be included. For proxy requests, the
1737 URL to be matched is of the form
1738 <code>scheme://servername/path</code>, and you must include the
1741 <p>The URL may use wildcards. In a wild-card string, <code>?</code> matches
1742 any single character, and <code>*</code> matches any sequences of
1746 expressions can also be used, with the addition of the
1747 <code>~</code> character. For example:</p>
1749 <div class="example"><p><code>
1750 <Location ~ "/(extra|special)/data">
1753 <p>would match URLs that contained the substring <code>/extra/data</code>
1754 or <code>/special/data</code>. The directive <code class="directive"><a href="#locationmatch"><LocationMatch></a></code> behaves
1755 identical to the regex version of <code class="directive"><Location></code>.</p>
1757 <p>The <code class="directive"><Location></code>
1758 functionality is especially useful when combined with the
1759 <code class="directive"><a href="#sethandler">SetHandler</a></code>
1760 directive. For example, to enable status requests, but allow them
1761 only from browsers at <code>foo.com</code>, you might use:</p>
1763 <div class="example"><p><code>
1764 <Location /status><br />
1765 <span class="indent">
1766 SetHandler server-status<br />
1767 Order Deny,Allow<br />
1769 Allow from .foo.com<br />
1774 <div class="note"><h3>Note about / (slash)</h3>
1775 <p>The slash character has special meaning depending on where in a
1776 URL it appears. People may be used to its behavior in the filesystem
1777 where multiple adjacent slashes are frequently collapsed to a single
1778 slash (<em>i.e.</em>, <code>/home///foo</code> is the same as
1779 <code>/home/foo</code>). In URL-space this is not necessarily true.
1780 The <code class="directive"><a href="#locationmatch"><LocationMatch></a></code>
1781 directive and the regex version of <code class="directive"><Location></code> require you to explicitly specify multiple
1782 slashes if that is your intention.</p>
1784 <p>For example, <code><LocationMatch ^/abc></code> would match
1785 the request URL <code>/abc</code> but not the request URL <code>
1786 //abc</code>. The (non-regex) <code class="directive"><Location></code> directive behaves similarly when used for
1787 proxy requests. But when (non-regex) <code class="directive"><Location></code> is used for non-proxy requests it will
1788 implicitly match multiple slashes with a single slash. For example,
1789 if you specify <code><Location /abc/def></code> and the
1790 request is to <code>/abc//def</code> then it will match.</p>
1795 <li><a href="../sections.html">How <Directory>, <Location>
1796 and <Files> sections work</a> for an explanation of how these
1797 different sections are combined when a request is received</li>
1800 <div class="top"><a href="#page-header"><img alt="top" src="../images/up.gif" /></a></div>
1801 <div class="directive-section"><h2><a name="LocationMatch" id="LocationMatch"><LocationMatch></a> <a name="locationmatch" id="locationmatch">Directive</a></h2>
1802 <table class="directive">
1803 <tr><th><a href="directive-dict.html#Description">Description:</a></th><td>Applies the enclosed directives only to regular-expression
1804 matching URLs</td></tr>
1805 <tr><th><a href="directive-dict.html#Syntax">Syntax:</a></th><td><code><LocationMatch
1806 <var>regex</var>> ... </LocationMatch></code></td></tr>
1807 <tr><th><a href="directive-dict.html#Context">Context:</a></th><td>server config, virtual host</td></tr>
1808 <tr><th><a href="directive-dict.html#Status">Status:</a></th><td>Core</td></tr>
1809 <tr><th><a href="directive-dict.html#Module">Module:</a></th><td>core</td></tr>
1811 <p>The <code class="directive"><LocationMatch></code> directive
1812 limits the scope of the enclosed directives by URL, in an identical manner
1813 to <code class="directive"><a href="#location"><Location></a></code>. However,
1814 it takes a regular expression as an argument instead of a simple
1815 string. For example:</p>
1817 <div class="example"><p><code>
1818 <LocationMatch "/(extra|special)/data">
1821 <p>would match URLs that contained the substring <code>/extra/data</code>
1822 or <code>/special/data</code>.</p>
1826 <li><a href="../sections.html">How <Directory>, <Location>
1827 and <Files> sections work</a> for an explanation of how these
1828 different sections are combined when a request is received</li>
1831 <div class="top"><a href="#page-header"><img alt="top" src="../images/up.gif" /></a></div>
1832 <div class="directive-section"><h2><a name="LogLevel" id="LogLevel">LogLevel</a> <a name="loglevel" id="loglevel">Directive</a></h2>
1833 <table class="directive">
1834 <tr><th><a href="directive-dict.html#Description">Description:</a></th><td>Controls the verbosity of the ErrorLog</td></tr>
1835 <tr><th><a href="directive-dict.html#Syntax">Syntax:</a></th><td><code>LogLevel <var>level</var></code></td></tr>
1836 <tr><th><a href="directive-dict.html#Default">Default:</a></th><td><code>LogLevel warn</code></td></tr>
1837 <tr><th><a href="directive-dict.html#Context">Context:</a></th><td>server config, virtual host</td></tr>
1838 <tr><th><a href="directive-dict.html#Status">Status:</a></th><td>Core</td></tr>
1839 <tr><th><a href="directive-dict.html#Module">Module:</a></th><td>core</td></tr>
1841 <p><code class="directive">LogLevel</code> adjusts the verbosity of the
1842 messages recorded in the error logs (see <code class="directive"><a href="#errorlog">ErrorLog</a></code> directive). The following
1843 <var>level</var>s are available, in order of decreasing
1846 <table class="bordered">
1848 <th><strong>Level</strong> </th>
1850 <th><strong>Description</strong> </th>
1852 <th><strong>Example</strong> </th>
1856 <td><code>emerg</code> </td>
1858 <td>Emergencies - system is unusable.</td>
1860 <td>"Child cannot open lock file. Exiting"</td>
1864 <td><code>alert</code> </td>
1866 <td>Action must be taken immediately.</td>
1868 <td>"getpwuid: couldn't determine user name from uid"</td>
1872 <td><code>crit</code> </td>
1874 <td>Critical Conditions.</td>
1876 <td>"socket: Failed to get a socket, exiting child"</td>
1880 <td><code>error</code> </td>
1882 <td>Error conditions.</td>
1884 <td>"Premature end of script headers"</td>
1888 <td><code>warn</code> </td>
1890 <td>Warning conditions.</td>
1892 <td>"child process 1234 did not exit, sending another
1897 <td><code>notice</code> </td>
1899 <td>Normal but significant condition.</td>
1901 <td>"httpd: caught SIGBUS, attempting to dump core in
1906 <td><code>info</code> </td>
1908 <td>Informational.</td>
1910 <td>"Server seems busy, (you may need to increase
1911 StartServers, or Min/MaxSpareServers)..."</td>
1915 <td><code>debug</code> </td>
1917 <td>Debug-level messages</td>
1919 <td>"Opening config file ..."</td>
1923 <p>When a particular level is specified, messages from all
1924 other levels of higher significance will be reported as well.
1925 <em>E.g.</em>, when <code>LogLevel info</code> is specified,
1926 then messages with log levels of <code>notice</code> and
1927 <code>warn</code> will also be posted.</p>
1929 <p>Using a level of at least <code>crit</code> is
1934 <div class="example"><p><code>
1939 <div class="top"><a href="#page-header"><img alt="top" src="../images/up.gif" /></a></div>
1940 <div class="directive-section"><h2><a name="MaxKeepAliveRequests" id="MaxKeepAliveRequests">MaxKeepAliveRequests</a> <a name="maxkeepaliverequests" id="maxkeepaliverequests">Directive</a></h2>
1941 <table class="directive">
1942 <tr><th><a href="directive-dict.html#Description">Description:</a></th><td>Number of requests allowed on a persistent
1943 connection</td></tr>
1944 <tr><th><a href="directive-dict.html#Syntax">Syntax:</a></th><td><code>MaxKeepAliveRequests <var>number</var></code></td></tr>
1945 <tr><th><a href="directive-dict.html#Default">Default:</a></th><td><code>MaxKeepAliveRequests 100</code></td></tr>
1946 <tr><th><a href="directive-dict.html#Context">Context:</a></th><td>server config, virtual host</td></tr>
1947 <tr><th><a href="directive-dict.html#Status">Status:</a></th><td>Core</td></tr>
1948 <tr><th><a href="directive-dict.html#Module">Module:</a></th><td>core</td></tr>
1950 <p>The <code class="directive">MaxKeepAliveRequests</code> directive
1951 limits the number of requests allowed per connection when
1952 <code class="directive"><a href="#keepalive">KeepAlive</a></code> is on. If it is
1953 set to <code>0</code>, unlimited requests will be allowed. We
1954 recommend that this setting be kept to a high value for maximum
1955 server performance.</p>
1959 <div class="example"><p><code>
1960 MaxKeepAliveRequests 500
1964 <div class="top"><a href="#page-header"><img alt="top" src="../images/up.gif" /></a></div>
1965 <div class="directive-section"><h2><a name="NameVirtualHost" id="NameVirtualHost">NameVirtualHost</a> <a name="namevirtualhost" id="namevirtualhost">Directive</a></h2>
1966 <table class="directive">
1967 <tr><th><a href="directive-dict.html#Description">Description:</a></th><td>Designates an IP address for name-virtual
1969 <tr><th><a href="directive-dict.html#Syntax">Syntax:</a></th><td><code>NameVirtualHost <var>addr</var>[:<var>port</var>]</code></td></tr>
1970 <tr><th><a href="directive-dict.html#Context">Context:</a></th><td>server config</td></tr>
1971 <tr><th><a href="directive-dict.html#Status">Status:</a></th><td>Core</td></tr>
1972 <tr><th><a href="directive-dict.html#Module">Module:</a></th><td>core</td></tr>
1974 <p>The <code class="directive">NameVirtualHost</code> directive is a
1975 required directive if you want to configure <a href="../vhosts/">name-based virtual hosts</a>.</p>
1977 <p>Although <var>addr</var> can be hostname it is recommended
1978 that you always use an IP address, e.g.</p>
1980 <div class="example"><p><code>
1981 NameVirtualHost 111.22.33.44
1984 <p>With the <code class="directive">NameVirtualHost</code> directive you
1985 specify the IP address on which the server will receive requests
1986 for the name-based virtual hosts. This will usually be the address
1987 to which your name-based virtual host names resolve. In cases
1988 where a firewall or other proxy receives the requests and forwards
1989 them on a different IP address to the server, you must specify the
1990 IP address of the physical interface on the machine which will be
1991 servicing the requests. If you have multiple name-based hosts on
1992 multiple addresses, repeat the directive for each address.</p>
1994 <div class="note"><h3>Note</h3>
1995 <p>Note, that the "main server" and any <code>_default_</code> servers
1996 will <strong>never</strong> be served for a request to a
1997 <code class="directive">NameVirtualHost</code> IP Address (unless for some
1998 reason you specify <code class="directive">NameVirtualHost</code> but then
1999 don't define any <code class="directive">VirtualHost</code>s for that
2003 <p>Optionally you can specify a port number on which the
2004 name-based virtual hosts should be used, e.g.</p>
2006 <div class="example"><p><code>
2007 NameVirtualHost 111.22.33.44:8080
2010 <p>IPv6 addresses must be enclosed in square brackets, as shown
2011 in the following example:</p>
2013 <div class="example"><p><code>
2014 NameVirtualHost [fe80::a00:20ff:fea7:ccea]:8080
2017 <p>To receive requests on all interfaces, you can use an argument of
2020 <div class="example"><p><code>
2024 <div class="note"><h3>Argument to <code class="directive"><VirtualHost></code>
2026 <p>Note that the argument to the <code class="directive"><VirtualHost></code> directive must
2027 exactly match the argument to the <code class="directive">NameVirtualHost</code> directive.</p>
2029 <div class="example"><p><code>
2030 NameVirtualHost 1.2.3.4<br />
2031 <VirtualHost 1.2.3.4><br />
2033 </VirtualHost><br />
2039 <li><a href="../vhosts/">Virtual Hosts
2040 documentation</a></li>
2043 <div class="top"><a href="#page-header"><img alt="top" src="../images/up.gif" /></a></div>
2044 <div class="directive-section"><h2><a name="Options" id="Options">Options</a> <a name="options" id="options">Directive</a></h2>
2045 <table class="directive">
2046 <tr><th><a href="directive-dict.html#Description">Description:</a></th><td>Configures what features are available in a particular
2048 <tr><th><a href="directive-dict.html#Syntax">Syntax:</a></th><td><code>Options
2049 [+|-]<var>option</var> [[+|-]<var>option</var>] ...</code></td></tr>
2050 <tr><th><a href="directive-dict.html#Default">Default:</a></th><td><code>Options All</code></td></tr>
2051 <tr><th><a href="directive-dict.html#Context">Context:</a></th><td>server config, virtual host, directory, .htaccess</td></tr>
2052 <tr><th><a href="directive-dict.html#Override">Override:</a></th><td>Options</td></tr>
2053 <tr><th><a href="directive-dict.html#Status">Status:</a></th><td>Core</td></tr>
2054 <tr><th><a href="directive-dict.html#Module">Module:</a></th><td>core</td></tr>
2056 <p>The <code class="directive">Options</code> directive controls which
2057 server features are available in a particular directory.</p>
2059 <p><var>option</var> can be set to <code>None</code>, in which
2060 case none of the extra features are enabled, or one or more of
2064 <dt><code>All</code></dt>
2066 <dd>All options except for <code>MultiViews</code>. This is the default
2069 <dt><code>ExecCGI</code></dt>
2072 Execution of CGI scripts is permitted.</dd>
2074 <dt><code>FollowSymLinks</code></dt>
2078 The server will follow symbolic links in this directory.
2080 <p>Even though the server follows the symlink it does <em>not</em>
2081 change the pathname used to match against <code class="directive"><a href="#directory"><Directory></a></code> sections.</p>
2082 <p>Note also, that this option <strong>gets ignored</strong> if set
2083 inside a <code class="directive"><a href="#location"><Location></a></code>
2087 <dt><code>Includes</code></dt>
2090 Server-side includes are permitted.</dd>
2092 <dt><code>IncludesNOEXEC</code></dt>
2096 Server-side includes are permitted, but the <code>#exec cmd</code>
2097 and <code>#exec cgi</code> are disabled. It is still possible to
2098 <code>#include virtual</code> CGI scripts from
2099 <code class="directive">ScriptAlias</code>e'd directories.</dd>
2101 <dt><code>Indexes</code></dt>
2104 If a URL which maps to a directory is requested, and the
2105 there is no <code class="directive">DirectoryIndex</code> (<em>e.g.</em>,
2106 <code>index.html</code>) in that directory, then the server will
2107 return a formatted listing of the directory.</dd>
2109 <dt><code>MultiViews</code></dt>
2112 <a href="../content-negotiation.html">Content negotiated</a>
2113 "MultiViews" are allowed.</dd>
2115 <dt><code>SymLinksIfOwnerMatch</code></dt>
2119 The server will only follow symbolic links for which the target
2120 file or directory is owned by the same user id as the link.<br /> <strong>Note</strong>: this option gets ignored if set inside
2121 a <code class="directive"><a href="#location"><Location></a></code>
2124 <p>Normally, if multiple <code class="directive">Options</code> could apply to a
2125 directory, then the most specific one is taken complete; the
2126 options are not merged. However if <em>all</em> the options on
2127 the <code class="directive">Options</code> directive are preceded by a
2128 <code>+</code> or <code>-</code>
2129 symbol, the options are merged. Any options preceded by a <code>+</code>
2130 are added to the options currently in force, and any options
2131 preceded by a <code>-</code> are removed from the options currently in
2134 <p>For example, without any <code>+</code> and <code>-</code> symbols:</p>
2136 <div class="example"><p><code>
2137 <Directory /web/docs><br />
2138 <span class="indent">
2139 Options Indexes FollowSymLinks<br />
2141 </Directory><br />
2143 <Directory /web/docs/spec><br />
2144 <span class="indent">
2145 Options Includes<br />
2150 <p>then only <code>Includes</code> will be set for the
2151 <code>/web/docs/spec</code> directory. However if the second
2152 <code class="directive">Options</code> directive uses the <code>+</code> and
2153 <code>-</code> symbols:</p>
2155 <div class="example"><p><code>
2156 <Directory /web/docs><br />
2157 <span class="indent">
2158 Options Indexes FollowSymLinks<br />
2160 </Directory><br />
2162 <Directory /web/docs/spec><br />
2163 <span class="indent">
2164 Options +Includes -Indexes<br />
2169 <p>then the options <code>FollowSymLinks</code> and
2170 <code>Includes</code> are set for the <code>/web/docs/spec</code>
2173 <div class="note"><h3>Note</h3>
2174 <p>Using <code>-IncludesNOEXEC</code> or
2175 <code>-Includes</code> disables server-side includes completely
2176 regardless of the previous setting.</p>
2179 <p>The default in the absence of any other settings is
2180 <code>All</code>.</p>
2183 <div class="top"><a href="#page-header"><img alt="top" src="../images/up.gif" /></a></div>
2184 <div class="directive-section"><h2><a name="Require" id="Require">Require</a> <a name="require" id="require">Directive</a></h2>
2185 <table class="directive">
2186 <tr><th><a href="directive-dict.html#Description">Description:</a></th><td>Selects which authenticated users can access
2187 a resource</td></tr>
2188 <tr><th><a href="directive-dict.html#Syntax">Syntax:</a></th><td><code>Require <var>entity-name</var> [<var>entity-name</var>] ...</code></td></tr>
2189 <tr><th><a href="directive-dict.html#Context">Context:</a></th><td>directory, .htaccess</td></tr>
2190 <tr><th><a href="directive-dict.html#Override">Override:</a></th><td>AuthConfig</td></tr>
2191 <tr><th><a href="directive-dict.html#Status">Status:</a></th><td>Core</td></tr>
2192 <tr><th><a href="directive-dict.html#Module">Module:</a></th><td>core</td></tr>
2194 <p>This directive selects which authenticated users can access
2195 a directory. The allowed syntaxes are:</p>
2198 <dt><code>Require user <var>userid</var> [<var>userid</var>]
2200 <dd>Only the named users can access the resource.</dd>
2202 <dt><code>Require group <var>group-name</var> [<var>group-name</var>]
2204 <dd>Only users in the named groups can access the resource.</dd>
2206 <dt><code>Require valid-user</code></dt>
2207 <dd>All valid users can access the resource.</dd>
2210 <p><code class="directive">Require</code> must be accompanied by
2211 <code class="directive"><a href="#authname">AuthName</a></code> and <code class="directive"><a href="#authtype">AuthType</a></code> directives, and directives such
2212 as <code class="directive"><a href="../mod/mod_authn_file.html#authuserfile">AuthUserFile</a></code>
2213 and <code class="directive"><a href="../mod/mod_authz_groupfile.html#authgroupfile">AuthGroupFile</a></code> (to
2214 define users and groups) in order to work correctly. Example:</p>
2216 <div class="example"><p><code>
2217 AuthType Basic<br />
2218 AuthName "Restricted Directory"<br />
2219 AuthUserFile /web/users<br />
2220 AuthGroupFile /web/groups<br />
2224 <p>Access controls which are applied in this way are effective for
2225 <strong>all</strong> methods. <strong>This is what is normally
2226 desired.</strong> If you wish to apply access controls only to
2227 specific methods, while leaving other methods unprotected, then
2228 place the <code class="directive">Require</code> statement into a
2229 <code class="directive"><a href="#limit"><Limit></a></code>
2234 <li><code class="directive"><a href="#satisfy">Satisfy</a></code></li>
2235 <li><code class="module"><a href="../mod/mod_authz_host.html">mod_authz_host</a></code></li>
2238 <div class="top"><a href="#page-header"><img alt="top" src="../images/up.gif" /></a></div>
2239 <div class="directive-section"><h2><a name="RLimitCPU" id="RLimitCPU">RLimitCPU</a> <a name="rlimitcpu" id="rlimitcpu">Directive</a></h2>
2240 <table class="directive">
2241 <tr><th><a href="directive-dict.html#Description">Description:</a></th><td>Limits the CPU consumption of processes launched
2242 by Apache children</td></tr>
2243 <tr><th><a href="directive-dict.html#Syntax">Syntax:</a></th><td><code>RLimitCPU <var>seconds</var>|max [<var>seconds</var>|max]</code></td></tr>
2244 <tr><th><a href="directive-dict.html#Default">Default:</a></th><td><code>Unset; uses operating system defaults</code></td></tr>
2245 <tr><th><a href="directive-dict.html#Context">Context:</a></th><td>server config, virtual host, directory, .htaccess</td></tr>
2246 <tr><th><a href="directive-dict.html#Override">Override:</a></th><td>All</td></tr>
2247 <tr><th><a href="directive-dict.html#Status">Status:</a></th><td>Core</td></tr>
2248 <tr><th><a href="directive-dict.html#Module">Module:</a></th><td>core</td></tr>
2250 <p>Takes 1 or 2 parameters. The first parameter sets the soft
2251 resource limit for all processes and the second parameter sets
2252 the maximum resource limit. Either parameter can be a number,
2253 or <code>max</code> to indicate to the server that the limit should
2254 be set to the maximum allowed by the operating system
2255 configuration. Raising the maximum resource limit requires that
2256 the server is running as <code>root</code>, or in the initial startup
2259 <p>This applies to processes forked off from Apache children
2260 servicing requests, not the Apache children themselves. This
2261 includes CGI scripts and SSI exec commands, but not any
2262 processes forked off from the Apache parent such as piped
2265 <p>CPU resource limits are expressed in seconds per
2270 <li><code class="directive"><a href="#rlimitmem">RLimitMEM</a></code></li>
2271 <li><code class="directive"><a href="#rlimitnproc">RLimitNPROC</a></code></li>
2274 <div class="top"><a href="#page-header"><img alt="top" src="../images/up.gif" /></a></div>
2275 <div class="directive-section"><h2><a name="RLimitMEM" id="RLimitMEM">RLimitMEM</a> <a name="rlimitmem" id="rlimitmem">Directive</a></h2>
2276 <table class="directive">
2277 <tr><th><a href="directive-dict.html#Description">Description:</a></th><td>Limits the memory consumption of processes launched
2278 by Apache children</td></tr>
2279 <tr><th><a href="directive-dict.html#Syntax">Syntax:</a></th><td><code>RLimitMEM <var>bytes</var>|max [<var>bytes</var>|max]</code></td></tr>
2280 <tr><th><a href="directive-dict.html#Default">Default:</a></th><td><code>Unset; uses operating system defaults</code></td></tr>
2281 <tr><th><a href="directive-dict.html#Context">Context:</a></th><td>server config, virtual host, directory, .htaccess</td></tr>
2282 <tr><th><a href="directive-dict.html#Override">Override:</a></th><td>All</td></tr>
2283 <tr><th><a href="directive-dict.html#Status">Status:</a></th><td>Core</td></tr>
2284 <tr><th><a href="directive-dict.html#Module">Module:</a></th><td>core</td></tr>
2286 <p>Takes 1 or 2 parameters. The first parameter sets the soft
2287 resource limit for all processes and the second parameter sets
2288 the maximum resource limit. Either parameter can be a number,
2289 or <code>max</code> to indicate to the server that the limit should
2290 be set to the maximum allowed by the operating system
2291 configuration. Raising the maximum resource limit requires that
2292 the server is running as <code>root</code>, or in the initial startup
2295 <p>This applies to processes forked off from Apache children
2296 servicing requests, not the Apache children themselves. This
2297 includes CGI scripts and SSI exec commands, but not any
2298 processes forked off from the Apache parent such as piped
2301 <p>Memory resource limits are expressed in bytes per
2306 <li><code class="directive"><a href="#rlimitcpu">RLimitCPU</a></code></li>
2307 <li><code class="directive"><a href="#rlimitnproc">RLimitNPROC</a></code></li>
2310 <div class="top"><a href="#page-header"><img alt="top" src="../images/up.gif" /></a></div>
2311 <div class="directive-section"><h2><a name="RLimitNPROC" id="RLimitNPROC">RLimitNPROC</a> <a name="rlimitnproc" id="rlimitnproc">Directive</a></h2>
2312 <table class="directive">
2313 <tr><th><a href="directive-dict.html#Description">Description:</a></th><td>Limits the number of processes that can be launched by
2314 processes launched by Apache children</td></tr>
2315 <tr><th><a href="directive-dict.html#Syntax">Syntax:</a></th><td><code>RLimitNPROC <var>number</var>|max [<var>number</var>|max]</code></td></tr>
2316 <tr><th><a href="directive-dict.html#Default">Default:</a></th><td><code>Unset; uses operating system defaults</code></td></tr>
2317 <tr><th><a href="directive-dict.html#Context">Context:</a></th><td>server config, virtual host, directory, .htaccess</td></tr>
2318 <tr><th><a href="directive-dict.html#Override">Override:</a></th><td>All</td></tr>
2319 <tr><th><a href="directive-dict.html#Status">Status:</a></th><td>Core</td></tr>
2320 <tr><th><a href="directive-dict.html#Module">Module:</a></th><td>core</td></tr>
2322 <p>Takes 1 or 2 parameters. The first parameter sets the soft
2323 resource limit for all processes and the second parameter sets
2324 the maximum resource limit. Either parameter can be a number,
2325 or <code>max</code> to indicate to the server that the limit
2326 should be set to the maximum allowed by the operating system
2327 configuration. Raising the maximum resource limit requires that
2328 the server is running as <code>root</code>, or in the initial startup
2331 <p>This applies to processes forked off from Apache children
2332 servicing requests, not the Apache children themselves. This
2333 includes CGI scripts and SSI exec commands, but not any
2334 processes forked off from the Apache parent such as piped
2337 <p>Process limits control the number of processes per user.</p>
2339 <div class="note"><h3>Note</h3>
2340 <p>If CGI processes are <strong>not</strong> running
2341 under userids other than the web server userid, this directive
2342 will limit the number of processes that the server itself can
2343 create. Evidence of this situation will be indicated by
2344 <strong><code>cannot fork</code></strong> messages in the
2345 <code>error_log</code>.</p>
2350 <li><code class="directive"><a href="#rlimitmem">RLimitMEM</a></code></li>
2351 <li><code class="directive"><a href="#rlimitcpu">RLimitCPU</a></code></li>
2354 <div class="top"><a href="#page-header"><img alt="top" src="../images/up.gif" /></a></div>
2355 <div class="directive-section"><h2><a name="Satisfy" id="Satisfy">Satisfy</a> <a name="satisfy" id="satisfy">Directive</a></h2>
2356 <table class="directive">
2357 <tr><th><a href="directive-dict.html#Description">Description:</a></th><td>Interaction between host-level access control and
2358 user authentication</td></tr>
2359 <tr><th><a href="directive-dict.html#Syntax">Syntax:</a></th><td><code>Satisfy Any|All</code></td></tr>
2360 <tr><th><a href="directive-dict.html#Default">Default:</a></th><td><code>Satisfy All</code></td></tr>
2361 <tr><th><a href="directive-dict.html#Context">Context:</a></th><td>directory, .htaccess</td></tr>
2362 <tr><th><a href="directive-dict.html#Override">Override:</a></th><td>AuthConfig</td></tr>
2363 <tr><th><a href="directive-dict.html#Status">Status:</a></th><td>Core</td></tr>
2364 <tr><th><a href="directive-dict.html#Module">Module:</a></th><td>core</td></tr>
2366 <p>Access policy if both <code class="directive"><a href="../mod/mod_authz_host.html#allow">Allow</a></code> and <code class="directive"><a href="#require">Require</a></code> used. The parameter can be
2367 either <code>All</code> or <code>Any</code>. This directive is only
2368 useful if access to a particular area is being restricted by both
2369 username/password <em>and</em> client host address. In this case
2370 the default behavior (<code>All</code>) is to require that the client
2371 passes the address access restriction <em>and</em> enters a valid
2372 username and password. With the <code>Any</code> option the client will be
2373 granted access if they either pass the host restriction or enter a
2374 valid username and password. This can be used to password restrict
2375 an area, but to let clients from particular addresses in without
2376 prompting for a password.</p>
2378 <p>For example, if you wanted to let people on your network have
2379 unrestricted access to a portion of your website, but require that
2380 people outside of your network provide a password, you could use a
2381 configuration similar to the following:</p>
2383 <div class="example"><p><code>
2384 Require valid-user<br />
2385 Allow from 192.168.1<br />
2392 <li><code class="directive"><a href="../mod/mod_authz_host.html#allow">Allow</a></code></li>
2393 <li><code class="directive"><a href="#require">Require</a></code></li>
2396 <div class="top"><a href="#page-header"><img alt="top" src="../images/up.gif" /></a></div>
2397 <div class="directive-section"><h2><a name="ScriptInterpreterSource" id="ScriptInterpreterSource">ScriptInterpreterSource</a> <a name="scriptinterpretersource" id="scriptinterpretersource">Directive</a></h2>
2398 <table class="directive">
2399 <tr><th><a href="directive-dict.html#Description">Description:</a></th><td>Technique for locating the interpreter for CGI
2401 <tr><th><a href="directive-dict.html#Syntax">Syntax:</a></th><td><code>ScriptInterpreterSource Registry|Registry-Strict|Script</code></td></tr>
2402 <tr><th><a href="directive-dict.html#Default">Default:</a></th><td><code>ScriptInterpreterSource Script</code></td></tr>
2403 <tr><th><a href="directive-dict.html#Context">Context:</a></th><td>server config, virtual host, directory, .htaccess</td></tr>
2404 <tr><th><a href="directive-dict.html#Override">Override:</a></th><td>FileInfo</td></tr>
2405 <tr><th><a href="directive-dict.html#Status">Status:</a></th><td>Core</td></tr>
2406 <tr><th><a href="directive-dict.html#Module">Module:</a></th><td>core</td></tr>
2407 <tr><th><a href="directive-dict.html#Compatibility">Compatibility:</a></th><td>Win32 only<br />
2408 option <code>Registry-Strict</code> is available in Apache 2.0 and
2411 <p>This directive is used to control how Apache finds the
2412 interpreter used to run CGI scripts. The default technique is to
2413 use the interpreter pointed to by the <code>#!</code> line in the
2416 <p>Setting <code>ScriptInterpreterSource Registry</code> will
2417 cause the Windows Registry to be searched using the script file
2418 extension (e.g., <code>.pl</code>) as a search key.</p>
2420 <p>The option <code>Registry-Strict</code> which is new in Apache 2.0
2421 does the same as <code>Registry</code> but uses a more strict registry
2425 <div class="top"><a href="#page-header"><img alt="top" src="../images/up.gif" /></a></div>
2426 <div class="directive-section"><h2><a name="ServerAdmin" id="ServerAdmin">ServerAdmin</a> <a name="serveradmin" id="serveradmin">Directive</a></h2>
2427 <table class="directive">
2428 <tr><th><a href="directive-dict.html#Description">Description:</a></th><td>Email address that the server includes in error
2429 messages sent to the client</td></tr>
2430 <tr><th><a href="directive-dict.html#Syntax">Syntax:</a></th><td><code>ServerAdmin <var>email-address</var></code></td></tr>
2431 <tr><th><a href="directive-dict.html#Context">Context:</a></th><td>server config, virtual host</td></tr>
2432 <tr><th><a href="directive-dict.html#Status">Status:</a></th><td>Core</td></tr>
2433 <tr><th><a href="directive-dict.html#Module">Module:</a></th><td>core</td></tr>
2435 <p>The <code class="directive">ServerAdmin</code> sets the e-mail address
2436 that the server includes in any error messages it returns to the
2439 <p>It may be worth setting up a dedicated address for this, e.g.</p>
2441 <div class="example"><p><code>
2442 ServerAdmin www-admin@foo.example.com
2444 <p>as users do not always mention that they are talking about the
2448 <div class="top"><a href="#page-header"><img alt="top" src="../images/up.gif" /></a></div>
2449 <div class="directive-section"><h2><a name="ServerAlias" id="ServerAlias">ServerAlias</a> <a name="serveralias" id="serveralias">Directive</a></h2>
2450 <table class="directive">
2451 <tr><th><a href="directive-dict.html#Description">Description:</a></th><td>Alternate names for a host used when matching requests
2452 to name-virtual hosts</td></tr>
2453 <tr><th><a href="directive-dict.html#Syntax">Syntax:</a></th><td><code>ServerAlias <var>hostname</var> [<var>hostname</var>] ...</code></td></tr>
2454 <tr><th><a href="directive-dict.html#Context">Context:</a></th><td>virtual host</td></tr>
2455 <tr><th><a href="directive-dict.html#Status">Status:</a></th><td>Core</td></tr>
2456 <tr><th><a href="directive-dict.html#Module">Module:</a></th><td>core</td></tr>
2458 <p>The <code class="directive">ServerAlias</code> directive sets the
2459 alternate names for a host, for use with <a href="../vhosts/name-based.html">name-based virtual hosts</a>.</p>
2461 <div class="example"><p><code>
2462 <VirtualHost *><br />
2463 ServerName server.domain.com<br />
2464 ServerAlias server server2.domain.com server2<br />
2466 </VirtualHost>
2471 <li><a href="../vhosts/">Apache Virtual Host documentation</a></li>
2474 <div class="top"><a href="#page-header"><img alt="top" src="../images/up.gif" /></a></div>
2475 <div class="directive-section"><h2><a name="ServerName" id="ServerName">ServerName</a> <a name="servername" id="servername">Directive</a></h2>
2476 <table class="directive">
2477 <tr><th><a href="directive-dict.html#Description">Description:</a></th><td>Hostname and port that the server uses to identify
2479 <tr><th><a href="directive-dict.html#Syntax">Syntax:</a></th><td><code>ServerName <var>fully-qualified-domain-name</var>[:<var>port</var>]</code></td></tr>
2480 <tr><th><a href="directive-dict.html#Context">Context:</a></th><td>server config, virtual host</td></tr>
2481 <tr><th><a href="directive-dict.html#Status">Status:</a></th><td>Core</td></tr>
2482 <tr><th><a href="directive-dict.html#Module">Module:</a></th><td>core</td></tr>
2483 <tr><th><a href="directive-dict.html#Compatibility">Compatibility:</a></th><td>In version 2.0, this
2484 directive supersedes the functionality of the <code class="directive">Port</code>
2485 directive from version 1.3.</td></tr>
2487 <p>The <code class="directive">ServerName</code> directive sets the hostname and
2488 port that the server uses to identify itself. This is used when
2489 creating redirection URLs. For example, if the name of the
2490 machine hosting the webserver is <code>simple.example.com</code>,
2491 but the machine also has the DNS alias <code>www.example.com</code>
2492 and you wish the webserver to be so identified, the following
2493 directive should be used:</p>
2495 <div class="example"><p><code>
2496 ServerName www.example.com:80
2499 <p>If no <code class="directive">ServerName</code> is specified, then the
2500 server attempts to deduce the hostname by performing a reverse
2501 lookup on the IP address. If no port is specified in the
2502 servername, then the server will use the port from the incoming
2503 request. For optimal reliability and predictability, you should
2504 specify an explicit hostname and port using the
2505 <code class="directive">ServerName</code> directive.</p>
2507 <p>If you are using <a href="../vhosts/name-based.html">name-based virtual hosts</a>,
2508 the <code class="directive">ServerName</code> inside a
2509 <code class="directive"><a href="#virtualhost"><VirtualHost></a></code>
2510 section specifies what hostname must appear in the request's
2511 <code>Host:</code> header to match this virtual host.</p>
2513 <p>See the description of the
2514 <code class="directive"><a href="#usecanonicalname">UseCanonicalName</a></code> directive for
2515 settings which determine whether self-referential URL's (e.g., by the
2516 <code class="module"><a href="../mod/mod_dir.html">mod_dir</a></code> module) will refer to the
2517 specified port, or to the port number given in the client's request.
2522 <li><a href="../dns-caveats.html">Issues Regarding DNS and
2524 <li><a href="../vhosts/">Apache virtual host
2525 documentation</a></li>
2526 <li><code class="directive"><a href="#usecanonicalname">UseCanonicalName</a></code></li>
2527 <li><code class="directive"><a href="#namevirtualhost">NameVirtualHost</a></code></li>
2528 <li><code class="directive"><a href="#serveralias">ServerAlias</a></code></li>
2531 <div class="top"><a href="#page-header"><img alt="top" src="../images/up.gif" /></a></div>
2532 <div class="directive-section"><h2><a name="ServerPath" id="ServerPath">ServerPath</a> <a name="serverpath" id="serverpath">Directive</a></h2>
2533 <table class="directive">
2534 <tr><th><a href="directive-dict.html#Description">Description:</a></th><td>Legacy URL pathname for a name-based virtual host that
2535 is accessed by an incompatible browser</td></tr>
2536 <tr><th><a href="directive-dict.html#Syntax">Syntax:</a></th><td><code>ServerPath <var>URL-path</var></code></td></tr>
2537 <tr><th><a href="directive-dict.html#Context">Context:</a></th><td>virtual host</td></tr>
2538 <tr><th><a href="directive-dict.html#Status">Status:</a></th><td>Core</td></tr>
2539 <tr><th><a href="directive-dict.html#Module">Module:</a></th><td>core</td></tr>
2541 <p>The <code class="directive">ServerPath</code> directive sets the legacy
2542 URL pathname for a host, for use with <a href="../vhosts/">name-based virtual hosts</a>.</p>
2546 <li><a href="../vhosts/">Apache Virtual Host documentation</a></li>
2549 <div class="top"><a href="#page-header"><img alt="top" src="../images/up.gif" /></a></div>
2550 <div class="directive-section"><h2><a name="ServerRoot" id="ServerRoot">ServerRoot</a> <a name="serverroot" id="serverroot">Directive</a></h2>
2551 <table class="directive">
2552 <tr><th><a href="directive-dict.html#Description">Description:</a></th><td>Base directory for the server installation</td></tr>
2553 <tr><th><a href="directive-dict.html#Syntax">Syntax:</a></th><td><code>ServerRoot <var>directory-path</var></code></td></tr>
2554 <tr><th><a href="directive-dict.html#Default">Default:</a></th><td><code>ServerRoot /usr/local/apache</code></td></tr>
2555 <tr><th><a href="directive-dict.html#Context">Context:</a></th><td>server config</td></tr>
2556 <tr><th><a href="directive-dict.html#Status">Status:</a></th><td>Core</td></tr>
2557 <tr><th><a href="directive-dict.html#Module">Module:</a></th><td>core</td></tr>
2559 <p>The <code class="directive">ServerRoot</code> directive sets the
2560 directory in which the server lives. Typically it will contain the
2561 subdirectories <code>conf/</code> and <code>logs/</code>. Relative
2562 paths for other configuration files are taken as relative to this
2565 <div class="example"><h3>Example</h3><p><code>
2566 ServerRoot /home/httpd
2572 <li><a href="../invoking.html">the <code>-d</code>
2573 option to <code>httpd</code></a></li>
2574 <li><a href="../misc/security_tips.html#serverroot">the
2575 security tips</a> for information on how to properly set
2576 permissions on the <code class="directive">ServerRoot</code></li>
2579 <div class="top"><a href="#page-header"><img alt="top" src="../images/up.gif" /></a></div>
2580 <div class="directive-section"><h2><a name="ServerSignature" id="ServerSignature">ServerSignature</a> <a name="serversignature" id="serversignature">Directive</a></h2>
2581 <table class="directive">
2582 <tr><th><a href="directive-dict.html#Description">Description:</a></th><td>Configures the footer on server-generated documents</td></tr>
2583 <tr><th><a href="directive-dict.html#Syntax">Syntax:</a></th><td><code>ServerSignature On|Off|EMail</code></td></tr>
2584 <tr><th><a href="directive-dict.html#Default">Default:</a></th><td><code>ServerSignature Off</code></td></tr>
2585 <tr><th><a href="directive-dict.html#Context">Context:</a></th><td>server config, virtual host, directory, .htaccess</td></tr>
2586 <tr><th><a href="directive-dict.html#Override">Override:</a></th><td>All</td></tr>
2587 <tr><th><a href="directive-dict.html#Status">Status:</a></th><td>Core</td></tr>
2588 <tr><th><a href="directive-dict.html#Module">Module:</a></th><td>core</td></tr>
2590 <p>The <code class="directive">ServerSignature</code> directive allows the
2591 configuration of a trailing footer line under server-generated
2592 documents (error messages, <code class="module"><a href="../mod/mod_proxy.html">mod_proxy</a></code> ftp directory
2593 listings, <code class="module"><a href="../mod/mod_info.html">mod_info</a></code> output, ...). The reason why you
2594 would want to enable such a footer line is that in a chain of proxies,
2595 the user often has no possibility to tell which of the chained servers
2596 actually produced a returned error message.</p>
2598 <p>The <code>Off</code>
2599 setting, which is the default, suppresses the footer line (and is
2600 therefore compatible with the behavior of Apache-1.2 and
2601 below). The <code>On</code> setting simply adds a line with the
2602 server version number and <code class="directive"><a href="#servername">ServerName</a></code> of the serving virtual host,
2603 and the <code>EMail</code> setting additionally creates a
2604 "mailto:" reference to the <code class="directive"><a href="#serveradmin">ServerAdmin</a></code> of the referenced
2607 <p>After version 2.0.44, the details of the server version number
2608 presented are controlled by the <code class="directive"><a href="#servertokens">ServerTokens</a></code> directive.</p>
2612 <li><code class="directive"><a href="#servertokens">ServerTokens</a></code></li>
2615 <div class="top"><a href="#page-header"><img alt="top" src="../images/up.gif" /></a></div>
2616 <div class="directive-section"><h2><a name="ServerTokens" id="ServerTokens">ServerTokens</a> <a name="servertokens" id="servertokens">Directive</a></h2>
2617 <table class="directive">
2618 <tr><th><a href="directive-dict.html#Description">Description:</a></th><td>Configures the Server HTTP response
2620 <tr><th><a href="directive-dict.html#Syntax">Syntax:</a></th><td><code>ServerTokens Major|Minor|Min[imal]|Prod[uctOnly]|OS|Full</code></td></tr>
2621 <tr><th><a href="directive-dict.html#Default">Default:</a></th><td><code>ServerTokens Full</code></td></tr>
2622 <tr><th><a href="directive-dict.html#Context">Context:</a></th><td>server config</td></tr>
2623 <tr><th><a href="directive-dict.html#Status">Status:</a></th><td>Core</td></tr>
2624 <tr><th><a href="directive-dict.html#Module">Module:</a></th><td>core</td></tr>
2626 <p>This directive controls whether <code>Server</code> response
2627 header field which is sent back to clients includes a
2628 description of the generic OS-type of the server as well as
2629 information about compiled-in modules.</p>
2632 <dt><code>ServerTokens Prod[uctOnly]</code></dt>
2634 <dd>Server sends (<em>e.g.</em>): <code>Server:
2637 <dt><code>ServerTokens Major</code></dt>
2639 <dd>Server sends (<em>e.g.</em>): <code>Server:
2640 Apache/2</code></dd>
2642 <dt><code>ServerTokens Minor</code></dt>
2644 <dd>Server sends (<em>e.g.</em>): <code>Server:
2645 Apache/2.0</code></dd>
2647 <dt><code>ServerTokens Min[imal]</code></dt>
2649 <dd>Server sends (<em>e.g.</em>): <code>Server:
2650 Apache/2.0.41</code></dd>
2652 <dt><code>ServerTokens OS</code></dt>
2654 <dd>Server sends (<em>e.g.</em>): <code>Server: Apache/2.0.41
2657 <dt><code>ServerTokens Full</code> (or not specified)</dt>
2659 <dd>Server sends (<em>e.g.</em>): <code>Server: Apache/2.0.41
2660 (Unix) PHP/4.2.2 MyMod/1.2</code></dd>
2663 <p>This setting applies to the entire server, and cannot be
2664 enabled or disabled on a virtualhost-by-virtualhost basis.</p>
2666 <p>After version 2.0.44, this directive also controls the
2667 information presented by the <code class="directive"><a href="#serversignature">ServerSignature</a></code> directive.</p>
2671 <li><code class="directive"><a href="#serversignature">ServerSignature</a></code></li>
2674 <div class="top"><a href="#page-header"><img alt="top" src="../images/up.gif" /></a></div>
2675 <div class="directive-section"><h2><a name="SetHandler" id="SetHandler">SetHandler</a> <a name="sethandler" id="sethandler">Directive</a></h2>
2676 <table class="directive">
2677 <tr><th><a href="directive-dict.html#Description">Description:</a></th><td>Forces all matching files to be processed by a
2679 <tr><th><a href="directive-dict.html#Syntax">Syntax:</a></th><td><code>SetHandler <var>handler-name</var>|None</code></td></tr>
2680 <tr><th><a href="directive-dict.html#Context">Context:</a></th><td>server config, virtual host, directory, .htaccess</td></tr>
2681 <tr><th><a href="directive-dict.html#Override">Override:</a></th><td>FileInfo</td></tr>
2682 <tr><th><a href="directive-dict.html#Status">Status:</a></th><td>Core</td></tr>
2683 <tr><th><a href="directive-dict.html#Module">Module:</a></th><td>core</td></tr>
2684 <tr><th><a href="directive-dict.html#Compatibility">Compatibility:</a></th><td>Moved into the core in Apache 2.0</td></tr>
2686 <p>When placed into an <code>.htaccess</code> file or a
2687 <code class="directive"><a href="#directory"><Directory></a></code> or
2688 <code class="directive"><a href="#location"><Location></a></code>
2689 section, this directive forces all matching files to be parsed
2690 through the <a href="../handler.html">handler</a> given by
2691 <var>handler-name</var>. For example, if you had a directory you
2692 wanted to be parsed entirely as imagemap rule files, regardless
2693 of extension, you might put the following into an
2694 <code>.htaccess</code> file in that directory:</p>
2696 <div class="example"><p><code>
2697 SetHandler imap-file
2700 <p>Another example: if you wanted to have the server display a
2701 status report whenever a URL of
2702 <code>http://servername/status</code> was called, you might put
2703 the following into <code>httpd.conf</code>:</p>
2705 <div class="example"><p><code>
2706 <Location /status><br />
2707 <span class="indent">
2708 SetHandler server-status<br />
2713 <p>You can override an earlier defined <code class="directive">SetHandler</code>
2714 directive by using the value <code>None</code>.</p>
2718 <li><code class="directive"><a href="../mod/mod_mime.html#addhandler">AddHandler</a></code></li>
2721 <div class="top"><a href="#page-header"><img alt="top" src="../images/up.gif" /></a></div>
2722 <div class="directive-section"><h2><a name="SetInputFilter" id="SetInputFilter">SetInputFilter</a> <a name="setinputfilter" id="setinputfilter">Directive</a></h2>
2723 <table class="directive">
2724 <tr><th><a href="directive-dict.html#Description">Description:</a></th><td>Sets the filters that will process client requests and POST
2726 <tr><th><a href="directive-dict.html#Syntax">Syntax:</a></th><td><code>SetInputFilter <var>filter</var>[;<var>filter</var>...]</code></td></tr>
2727 <tr><th><a href="directive-dict.html#Context">Context:</a></th><td>server config, virtual host, directory, .htaccess</td></tr>
2728 <tr><th><a href="directive-dict.html#Override">Override:</a></th><td>FileInfo</td></tr>
2729 <tr><th><a href="directive-dict.html#Status">Status:</a></th><td>Core</td></tr>
2730 <tr><th><a href="directive-dict.html#Module">Module:</a></th><td>core</td></tr>
2732 <p>The <code class="directive">SetInputFilter</code> directive sets the
2733 filter or filters which will process client requests and POST
2734 input when they are received by the server. This is in addition to
2735 any filters defined elsewhere, including the
2736 <code class="directive"><a href="../mod/mod_mime.html#addinputfilter">AddInputFilter</a></code>
2739 <p>If more than one filter is specified, they must be separated
2740 by semicolons in the order in which they should process the
2745 <li><a href="../filter.html">Filters</a> documentation</li>
2748 <div class="top"><a href="#page-header"><img alt="top" src="../images/up.gif" /></a></div>
2749 <div class="directive-section"><h2><a name="SetOutputFilter" id="SetOutputFilter">SetOutputFilter</a> <a name="setoutputfilter" id="setoutputfilter">Directive</a></h2>
2750 <table class="directive">
2751 <tr><th><a href="directive-dict.html#Description">Description:</a></th><td>Sets the filters that will process responses from the
2753 <tr><th><a href="directive-dict.html#Syntax">Syntax:</a></th><td><code>SetOutputFilter <var>filter</var>[;<var>filter</var>...]</code></td></tr>
2754 <tr><th><a href="directive-dict.html#Context">Context:</a></th><td>server config, virtual host, directory, .htaccess</td></tr>
2755 <tr><th><a href="directive-dict.html#Override">Override:</a></th><td>FileInfo</td></tr>
2756 <tr><th><a href="directive-dict.html#Status">Status:</a></th><td>Core</td></tr>
2757 <tr><th><a href="directive-dict.html#Module">Module:</a></th><td>core</td></tr>
2759 <p>The <code class="directive">SetOutputFilter</code> directive sets the filters
2760 which will process responses from the server before they are
2761 sent to the client. This is in addition to any filters defined
2762 elsewhere, including the
2763 <code class="directive"><a href="../mod/mod_mime.html#addoutputfilter">AddOutputFilter</a></code>
2766 <p>For example, the following configuration will process all files
2767 in the <code>/www/data/</code> directory for server-side
2770 <div class="example"><p><code>
2771 <Directory /www/data/><br />
2772 <span class="indent">
2773 SetOutputFilter INCLUDES<br />
2778 <p>If more than one filter is specified, they must be separated
2779 by semicolons in the order in which they should process the
2784 <li><a href="../filter.html">Filters</a> documentation</li>
2787 <div class="top"><a href="#page-header"><img alt="top" src="../images/up.gif" /></a></div>
2788 <div class="directive-section"><h2><a name="TimeOut" id="TimeOut">TimeOut</a> <a name="timeout" id="timeout">Directive</a></h2>
2789 <table class="directive">
2790 <tr><th><a href="directive-dict.html#Description">Description:</a></th><td>Amount of time the server will wait for
2791 certain events before failing a request</td></tr>
2792 <tr><th><a href="directive-dict.html#Syntax">Syntax:</a></th><td><code>TimeOut <var>seconds</var></code></td></tr>
2793 <tr><th><a href="directive-dict.html#Default">Default:</a></th><td><code>TimeOut 300</code></td></tr>
2794 <tr><th><a href="directive-dict.html#Context">Context:</a></th><td>server config</td></tr>
2795 <tr><th><a href="directive-dict.html#Status">Status:</a></th><td>Core</td></tr>
2796 <tr><th><a href="directive-dict.html#Module">Module:</a></th><td>core</td></tr>
2798 <p>The <code class="directive">TimeOut</code> directive currently defines
2799 the amount of time Apache will wait for three things:</p>
2802 <li>The total amount of time it takes to receive a GET
2805 <li>The amount of time between receipt of TCP packets on a
2806 POST or PUT request.</li>
2808 <li>The amount of time between ACKs on transmissions of TCP
2809 packets in responses.</li>
2812 <p>We plan on making these separately configurable at some point
2813 down the road. The timer used to default to 1200 before 1.2,
2814 but has been lowered to 300 which is still far more than
2815 necessary in most situations. It is not set any lower by
2816 default because there may still be odd places in the code where
2817 the timer is not reset when a packet is sent. </p>
2820 <div class="top"><a href="#page-header"><img alt="top" src="../images/up.gif" /></a></div>
2821 <div class="directive-section"><h2><a name="UseCanonicalName" id="UseCanonicalName">UseCanonicalName</a> <a name="usecanonicalname" id="usecanonicalname">Directive</a></h2>
2822 <table class="directive">
2823 <tr><th><a href="directive-dict.html#Description">Description:</a></th><td>Configures how the server determines its own name and
2825 <tr><th><a href="directive-dict.html#Syntax">Syntax:</a></th><td><code>UseCanonicalName On|Off|DNS</code></td></tr>
2826 <tr><th><a href="directive-dict.html#Default">Default:</a></th><td><code>UseCanonicalName On</code></td></tr>
2827 <tr><th><a href="directive-dict.html#Context">Context:</a></th><td>server config, virtual host, directory</td></tr>
2828 <tr><th><a href="directive-dict.html#Status">Status:</a></th><td>Core</td></tr>
2829 <tr><th><a href="directive-dict.html#Module">Module:</a></th><td>core</td></tr>
2831 <p>In many situations Apache must construct a <em>self-referential</em>
2832 URL -- that is, a URL that refers back to the same server. With
2833 <code>UseCanonicalName On</code> Apache will use the hostname and port
2834 specified in the <code class="directive"><a href="#servername">ServerName</a></code>
2835 directive to construct the canonical name for the server. This name
2836 is used in all self-referential URLs, and for the values of
2837 <code>SERVER_NAME</code> and <code>SERVER_PORT</code> in CGIs.</p>
2839 <p>With <code>UseCanonicalName Off</code> Apache will form
2840 self-referential URLs using the hostname and port supplied by
2841 the client if any are supplied (otherwise it will use the
2842 canonical name, as defined above). These values are the same
2843 that are used to implement <a href="../vhosts/name-based.html">name based virtual hosts</a>,
2844 and are available with the same clients. The CGI variables
2845 <code>SERVER_NAME</code> and <code>SERVER_PORT</code> will be
2846 constructed from the client supplied values as well.</p>
2848 <p>An example where this may be useful is on an intranet server
2849 where you have users connecting to the machine using short
2850 names such as <code>www</code>. You'll notice that if the users
2851 type a shortname, and a URL which is a directory, such as
2852 <code>http://www/splat</code>, <em>without the trailing
2853 slash</em> then Apache will redirect them to
2854 <code>http://www.domain.com/splat/</code>. If you have
2855 authentication enabled, this will cause the user to have to
2856 authenticate twice (once for <code>www</code> and once again
2857 for <code>www.domain.com</code> -- see <a href="http://httpd.apache.org/docs/misc/FAQ.html#prompted-twice">the
2858 FAQ on this subject for more information</a>). But if
2859 <code class="directive">UseCanonicalName</code> is set <code>Off</code>, then
2860 Apache will redirect to <code>http://www/splat/</code>.</p>
2862 <p>There is a third option, <code>UseCanonicalName DNS</code>,
2863 which is intended for use with mass IP-based virtual hosting to
2864 support ancient clients that do not provide a
2865 <code>Host:</code> header. With this option Apache does a
2866 reverse DNS lookup on the server IP address that the client
2867 connected to in order to work out self-referential URLs.</p>
2869 <div class="warning"><h3>Warning</h3>
2870 <p>If CGIs make assumptions about the values of <code>SERVER_NAME</code>
2871 they may be broken by this option. The client is essentially free
2872 to give whatever value they want as a hostname. But if the CGI is
2873 only using <code>SERVER_NAME</code> to construct self-referential URLs
2874 then it should be just fine.</p>
2879 <li><code class="directive"><a href="#servername">ServerName</a></code></li>
2880 <li><code class="directive"><a href="../mod/mpm_common.html#listen">Listen</a></code></li>
2883 <div class="top"><a href="#page-header"><img alt="top" src="../images/up.gif" /></a></div>
2884 <div class="directive-section"><h2><a name="VirtualHost" id="VirtualHost"><VirtualHost></a> <a name="virtualhost" id="virtualhost">Directive</a></h2>
2885 <table class="directive">
2886 <tr><th><a href="directive-dict.html#Description">Description:</a></th><td>Contains directives that apply only to a specific
2887 hostname or IP address</td></tr>
2888 <tr><th><a href="directive-dict.html#Syntax">Syntax:</a></th><td><code><VirtualHost
2889 <var>addr</var>[:<var>port</var>] [<var>addr</var>[:<var>port</var>]]
2890 ...> ... </VirtualHost></code></td></tr>
2891 <tr><th><a href="directive-dict.html#Context">Context:</a></th><td>server config</td></tr>
2892 <tr><th><a href="directive-dict.html#Status">Status:</a></th><td>Core</td></tr>
2893 <tr><th><a href="directive-dict.html#Module">Module:</a></th><td>core</td></tr>
2895 <p><code class="directive"><VirtualHost></code> and
2896 <code></VirtualHost></code> are used to enclose a group of
2897 directives that will apply only to a particular virtual host. Any
2898 directive that is allowed in a virtual host context may be
2899 used. When the server receives a request for a document on a
2900 particular virtual host, it uses the configuration directives
2901 enclosed in the <code class="directive"><VirtualHost></code>
2902 section. <var>Addr</var> can be:</p>
2905 <li>The IP address of the virtual host;</li>
2907 <li>A fully qualified domain name for the IP address of the
2910 <li>The character <code>*</code>, which is used only in combination with
2911 <code>NameVirtualHost *</code> to match all IP addresses; or</li>
2913 <li>The string <code>_default_</code>, which is used only
2914 with IP virtual hosting to catch unmatched IP addresses.</li>
2917 <div class="example"><h3>Example</h3><p><code>
2918 <VirtualHost 10.1.2.3><br />
2919 <span class="indent">
2920 ServerAdmin webmaster@host.foo.com<br />
2921 DocumentRoot /www/docs/host.foo.com<br />
2922 ServerName host.foo.com<br />
2923 ErrorLog logs/host.foo.com-error_log<br />
2924 TransferLog logs/host.foo.com-access_log<br />
2926 </VirtualHost>
2930 <p>IPv6 addresses must be specified in square brackets because
2931 the optional port number could not be determined otherwise. An
2932 IPv6 example is shown below:</p>
2934 <div class="example"><p><code>
2935 <VirtualHost [fe80::a00:20ff:fea7:ccea]><br />
2936 <span class="indent">
2937 ServerAdmin webmaster@host.example.com<br />
2938 DocumentRoot /www/docs/host.example.com<br />
2939 ServerName host.example.com<br />
2940 ErrorLog logs/host.example.com-error_log<br />
2941 TransferLog logs/host.example.com-access_log<br />
2943 </VirtualHost>
2946 <p>Each Virtual Host must correspond to a different IP address,
2947 different port number or a different host name for the server,
2948 in the former case the server machine must be configured to
2949 accept IP packets for multiple addresses. (If the machine does
2950 not have multiple network interfaces, then this can be
2951 accomplished with the <code>ifconfig alias</code> command -- if
2952 your OS supports it).</p>
2954 <div class="note"><h3>Note</h3>
2955 <p>The use of <code class="directive"><VirtualHost></code> does
2956 <strong>not</strong> affect what addresses Apache listens on. You
2957 may need to ensure that Apache is listening on the correct addresses
2958 using <code class="directive"><a href="../mod/mpm_common.html#listen">Listen</a></code>.</p>
2961 <p>When using IP-based virtual hosting, the special name
2962 <code>_default_</code> can be specified in
2963 which case this virtual host will match any IP address that is
2964 not explicitly listed in another virtual host. In the absence
2965 of any <code>_default_</code> virtual host the "main" server config,
2966 consisting of all those definitions outside any VirtualHost
2967 section, is used when no IP-match occurs. (But note that any IP
2968 address that matches a <code class="directive"><a href="#namevirtualhost">NameVirtualHost</a></code> directive will use neither
2969 the "main" server config nor the <code>_default_</code> virtual host.
2970 See the <a href="../vhosts/name-based.html">name-based virtual hosting</a>
2971 documentation for further details.)</p>
2973 <p>You can specify a <code>:port</code> to change the port that is
2974 matched. If unspecified then it defaults to the same port as the
2975 most recent <code class="directive"><a href="../mod/mpm_common.html#listen">Listen</a></code>
2976 statement of the main server. You may also specify <code>:*</code>
2977 to match all ports on that address. (This is recommended when used
2978 with <code>_default_</code>.)</p>
2980 <div class="warning"><h3>Security</h3>
2981 <p>See the <a href="../misc/security_tips.html">security tips</a>
2982 document for details on why your security could be compromised if the
2983 directory where logfiles are stored is writable by anyone other
2984 than the user that starts the server.</p>
2989 <li><a href="../vhosts/">Apache Virtual Host documentation</a></li>
2990 <li><a href="../dns-caveats.html">Issues Regarding DNS and
2992 <li><a href="../bind.html">Setting
2993 which addresses and ports Apache uses</a></li>
2994 <li><a href="../sections.html">How <Directory>, <Location>
2995 and <Files> sections work</a> for an explanation of how these
2996 different sections are combined when a request is received</li>
3000 <div class="bottomlang">
3001 <p><span>Available Languages: </span><a href="../de/mod/core.html"> de </a> | <a href="../en/mod/core.html"> en </a></p>
3002 </div><div id="footer">
3003 <p class="apache">Maintained by the <a href="http://httpd.apache.org/docs-project/">Apache HTTP Server Documentation Project</a></p>
3004 <p class="menu"><a href="../mod/">Modules</a> | <a href="../mod/directives.html">Directives</a> | <a href="../faq/">FAQ</a> | <a href="../glossary.html">Glossary</a> | <a href="../sitemap.html">Sitemap</a></p></div>