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 <TITLE>Apache Core Features</TITLE>
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 <H1 ALIGN="CENTER">Apache Core Features</H1>
 <P>
 These configuration parameters control the core Apache features, and are
 always available.
 </P>
 <H2>Directives</H2>
 <UL>
 <LI><A HREF="#accessfilename">AccessFileName</A>
 <LI><A HREF="#adddefaultcharset">AddDefaultCharset</A>
 <LI><A HREF="#addmodule">AddModule</A>
 <LI><A HREF="#allowoverride">AllowOverride</A>
 <LI><A HREF="#authname">AuthName</A>
 <LI><A HREF="#authtype">AuthType</A>
 <LI><A HREF="#clearmodulelist">ClearModuleList</A>
 <LI><A HREF="#contentdigest">ContentDigest</A>
 <LI><A HREF="#coredumpdirectory">CoreDumpDirectory</A>
 <LI><A HREF="#defaulttype">DefaultType</A>
 <LI><A HREF="#directory">&lt;Directory&gt;</A>
 <LI><A HREF="#directorymatch">&lt;DirectoryMatch&gt;</A>
 <LI><A HREF="#documentroot">DocumentRoot</A>
 <LI><A HREF="#errordocument">ErrorDocument</A>
 <LI><A HREF="#errorlog">ErrorLog</A>
 <LI><A HREF="#files">&lt;Files&gt;</A>
 <LI><A HREF="#filesmatch">&lt;FilesMatch&gt;</A>
 <LI><A HREF="#hostnamelookups">HostNameLookups</A>
 <LI><A HREF="#identitycheck">IdentityCheck</A>
 <LI><A HREF="#ifdefine">&lt;IfDefine&gt;</A>
 <LI><A HREF="#ifmodule">&lt;IfModule&gt;</A>
 <LI><A HREF="#include">Include</A>
 <LI><A HREF="#keepalive">KeepAlive</A>
 <LI><A HREF="#keepalivetimeout">KeepAliveTimeout</A>
 <LI><A HREF="#limit">&lt;Limit&gt;</A>
 <LI><A HREF="#limitexcept">&lt;LimitExcept&gt;</A>
 <LI><A HREF="#limitrequestbody">LimitRequestBody</A>
 <LI><A HREF="#limitrequestfields">LimitRequestFields</A>
 <LI><A HREF="#limitrequestfieldsize">LimitRequestFieldsize</A>
 <LI><A HREF="#limitrequestline">LimitRequestLine</A>
 <LI><A HREF="#limitxmlrequestbody">LimitXMLRequestBody</A>
 <LI><A HREF="#location">&lt;Location&gt;</A>
 <LI><A HREF="#locationmatch">&lt;LocationMatch&gt;</A>
 <LI><A HREF="#loglevel">LogLevel</A>
 <LI><A HREF="#maxkeepaliverequests">MaxKeepAliveRequests</A>
 <LI><A HREF="#namevirtualhost">NameVirtualHost</A>
 <LI><A HREF="#options">Options</A>
 <LI><A HREF="#port">Port</A>
 <LI><A HREF="#require">Require</A>
 <LI><A HREF="#rlimitcpu">RLimitCPU</A>
 <LI><A HREF="#rlimitmem">RLimitMEM</A>
 <LI><A HREF="#rlimitnproc">RLimitNPROC</A>
 <LI><A HREF="#satisfy">Satisfy</A>
 <LI><A HREF="#scriptinterpretersource">ScriptInterpreterSource</A>
 <LI><A HREF="#serveradmin">ServerAdmin</A>
 <LI><A HREF="#serveralias">ServerAlias</A>
 <LI><A HREF="#servername">ServerName</A>
 <LI><A HREF="#serverpath">ServerPath</A>
 <LI><A HREF="#serverroot">ServerRoot</A>
 <LI><A HREF="#serversignature">ServerSignature</A>
 <LI><A HREF="#servertokens">ServerTokens</A>
 <LI><A HREF="#setinputfilter">SetInputFilter</A>
 <LI><A HREF="#setoutputfilter">SetOutputFilter</A>
 <LI><A HREF="#timeout">TimeOut</A>
 <LI><A HREF="#usecanonicalname">UseCanonicalName</A>
 <LI><A HREF="#virtualhost">&lt;VirtualHost&gt;</A>
 </UL>
 <HR>

 <H2><A NAME="accessfilename">AccessFileName directive</A></H2>
 <!--%plaintext &lt;?INDEX {\tt AccessFileName} directive&gt; -->
 <A
  HREF="directive-dict.html#Syntax"
  REL="Help"
 ><STRONG>Syntax:</STRONG></A> AccessFileName <EM>filename</em>
 [<em>filename</em>] ...<BR>
 <A
  HREF="directive-dict.html#Default"
  REL="Help"
 ><STRONG>Default:</STRONG></A> <CODE>AccessFileName .htaccess</CODE><BR>
 <A
  HREF="directive-dict.html#Context"
  REL="Help"
 ><STRONG>Context:</STRONG></A> server config, virtual host<BR>
 <A
  HREF="directive-dict.html#Status"
  REL="Help"
 ><STRONG>Status:</STRONG></A> core<BR>
 <A
  HREF="directive-dict.html#Compatibility"
  REL="Help"
 ><STRONG>Compatibility:</STRONG></A> AccessFileName can accept more than
 one filename only in Apache 1.3 and later<P>

 When returning a document to the client the server looks for the first existing
 access control file from this list of names in every directory of the path to
 the document, if access control files are enabled for that directory.

 For example:
 <BLOCKQUOTE><CODE>AccessFileName .acl</CODE></BLOCKQUOTE>
 before returning the document /usr/local/web/index.html, the
 server will read /.acl, /usr/.acl, /usr/local/.acl and /usr/local/web/.acl
 for directives, unless they have been disabled with
 <BLOCKQUOTE><CODE>
 &lt;Directory /&gt;<BR>
 AllowOverride None<BR>
 &lt;/Directory&gt;</CODE>
 </BLOCKQUOTE><P>

 <P><STRONG>See Also:</STRONG>
 <A HREF="#allowoverride">AllowOverride</a></P>
 <HR>

 <H2><A NAME="adddefaultcharset">AddDefaultCharset directive</A></H2>
 <A HREF="directive-dict.html#Syntax" REL="Help"><STRONG>Syntax:</STRONG></A>
 AddDefaultCharset On|Off|<em>charset</em><BR>
 <A HREF="directive-dict.html#Context" REL="Help" ><STRONG>Context:</STRONG></A>
 all<BR>
 <A HREF="directive-dict.html#Status" REL="Help" ><STRONG>Status:</STRONG></A>
 core<BR>
 <A HREF="directive-dict.html#Default" REL="Help"><STRONG>Default:</STRONG></A>
 <CODE>AddDefaultCharset Off</CODE><BR>
 <A HREF="directive-dict.html#Compatibility" REL="Help"><STRONG>Compatibility:
 </STRONG></A> AddDefaultCharset is only available in Apache 1.3.12 and
 later<P>
 This directive specifies the name of the character set that will be added
 to any response that does not have any parameter on the content
 type in the HTTP headers. This will override any character set specified
 in the body of the document via a <CODE>META</CODE> tag. A setting
 of <CODE>AddDefaultCharset Off</CODE> disables this functionality.
 <CODE>AddDefaultCharset On</CODE> enables Apache's internal
 default charset of <code>iso-8859-1</code> as required by the
 directive. You can also specify an alternate <em>charset</em> to be used;
 e.g. <code>AddDefaultCharset utf-8</code>.
 <P><HR>

 <H2><A NAME="addmodule">AddModule directive</A></H2>
 <!--%plaintext &lt;?INDEX {\tt AddModule} directive&gt; -->
 <A
  HREF="directive-dict.html#Syntax"
  REL="Help"
 ><STRONG>Syntax:</STRONG></A> AddModule <EM>module</em> [<em>module</em>] ...<BR>
 <A
  HREF="directive-dict.html#Context"
  REL="Help"
 ><STRONG>Context:</STRONG></A> server config <BR>
 <A
  HREF="directive-dict.html#Status"
  REL="Help"
 ><STRONG>Status:</STRONG></A> core<BR>
 <A
  HREF="directive-dict.html#Compatibility"
  REL="Help"
 ><STRONG>Compatibility:</STRONG></A> AddModule is only available in
 Apache 1.2 and later<P>

 The server can have modules compiled in which are not actively in use.
 This directive can be used to enable the use of those modules.  The
 server comes with a pre-loaded list of active modules; this list can
 be cleared with the <A HREF="#clearmodulelist">ClearModuleList</A>
 directive.<P><HR>

 <H2><A NAME="allowoverride">AllowOverride directive</A></H2>
 <!--%plaintext &lt;?INDEX {\tt AllowOverride} directive&gt; -->
 <A
  HREF="directive-dict.html#Syntax"
  REL="Help"
 ><STRONG>Syntax:</STRONG></A> AllowOverride All|None|<EM>directive-type</em>
 [<em>directive-type</em>] ...<BR>
 <A
  HREF="directive-dict.html#Default"
  REL="Help"
 ><STRONG>Default:</STRONG></A> <CODE>AllowOverride All</CODE><BR>
 <A
  HREF="directive-dict.html#Context"
  REL="Help"
 ><STRONG>Context:</STRONG></A> directory<BR>
 <A
  HREF="directive-dict.html#Status"
  REL="Help"
 ><STRONG>Status:</STRONG></A> core<P>

 <p>When the server finds an .htaccess file (as specified by
 <A HREF="#accessfilename">AccessFileName</A>) it needs to know which
 directives declared in that file can override earlier access information.</p>

 <p>When this directive is set to <code>None</code>, then
 .htaccess files are completely ignored.  In this case, the server
 will not even attempt to read .htaccess files in the filesystem.</p>

 <p>When this directive is set to <code>All</code>, then any directive
 which has the .htaccess <a
 href="directive-dict.html#Context">Context</a> is allowed in .htaccess
 files.</p>

 <p>The <em>directive-type</em> can be one of the following groupings
 of directives.</p>
 <DL>
 <DT>AuthConfig
 <DD>
 <!--%plaintext &lt;?INDEX {\tt AuthConfig} override&gt; -->
 Allow use of the authorization directives
 (<A HREF="mod_auth_dbm.html#authdbmgroupfile">AuthDBMGroupFile</A>,
 <A HREF="mod_auth_dbm.html#authdbmuserfile">AuthDBMUserFile</A>,
 <A HREF="mod_auth.html#authgroupfile">AuthGroupFile</A>,
 <A HREF="#authname">AuthName</A>, <A HREF="#authtype">AuthType</A>,
 <A HREF="mod_auth.html#authuserfile">AuthUserFile</A>,
 <A HREF="#require">Require</A>, <EM>etc.</EM>).
 <DT>FileInfo
 <DD>
 <!--%plaintext &lt;?INDEX {\tt FileInfo} override&gt; -->
 Allow use of the directives controlling document types
 (<A HREF="mod_mime.html#addencoding">AddEncoding</A>,
 <A HREF="mod_mime.html#addlanguage">AddLanguage</A>,
 <A HREF="mod_mime.html#addtype">AddType</A>,
 <A HREF="#defaulttype">DefaultType</A>,
 <A HREF="#errordocument">ErrorDocument</A>,
 <A HREF="mod_negotiation.html#languagepriority">LanguagePriority</A>, <EM>etc.</EM>).
 <DT>Indexes
 <DD>
 <!--%plaintext &lt;?INDEX {\tt Indexes} override&gt; -->
 Allow use of the directives controlling directory indexing
 (<A HREF="mod_autoindex.html#adddescription">AddDescription</A>,
 <A HREF="mod_autoindex.html#addicon">AddIcon</A>,
 <A HREF="mod_autoindex.html#addiconbyencoding">AddIconByEncoding</A>,
 <A HREF="mod_autoindex.html#addiconbytype">AddIconByType</A>,
 <A HREF="mod_autoindex.html#defaulticon">DefaultIcon</A>,
 <A HREF="mod_dir.html#directoryindex">DirectoryIndex</A>,
 <A HREF="mod_autoindex.html#fancyindexing">FancyIndexing</A>,
 <A HREF="mod_autoindex.html#headername">HeaderName</A>,
 <A HREF="mod_autoindex.html#indexignore">IndexIgnore</A>,
 <A HREF="mod_autoindex.html#indexoptions">IndexOptions</A>,
 <A HREF="mod_autoindex.html#readmename">ReadmeName</A>, <EM>etc.</EM>).
 <DT>Limit
 <DD>
 <!--%plaintext &lt;?INDEX {\tt Limit} override&gt; -->
 Allow use of the directives controlling host access (Allow, Deny and Order).
 <DT>Options
 <DD>
 <!--%plaintext &lt;?INDEX {\tt Options} override&gt; -->
 Allow use of the directives controlling specific directory features
 (<A HREF="#options">Options</A> and
 <A HREF="mod_include.html#xbithack">XBitHack</A>).
 </DL><P>

 <P><STRONG>See Also:</STRONG>
 <A HREF="#accessfilename">AccessFileName</A></P>
 <HR>

 <H2><A NAME="authname">AuthName directive</A></H2>
 <!--%plaintext &lt;?INDEX {\tt AuthName} directive&gt; -->
 <A
  HREF="directive-dict.html#Syntax"
  REL="Help"
 ><STRONG>Syntax:</STRONG></A> AuthName <EM>auth-domain</EM><BR>
 <A
  HREF="directive-dict.html#Context"
  REL="Help"
 ><STRONG>Context:</STRONG></A> directory, .htaccess<BR>
 <A
  HREF="directive-dict.html#Override"
  REL="Help"
 ><STRONG>Override:</STRONG></A> AuthConfig<BR>
 <A
  HREF="directive-dict.html#Status"
  REL="Help"
 ><STRONG>Status:</STRONG></A> core<P>

 This directive sets the name of the authorization realm for a directory.
 This realm is given to the client so that the user knows which username and
 password to send.  <SAMP>AuthName</SAMP> takes a single argument;
 if the realm name contains spaces, it must be enclosed in quotation marks.
 It must be accompanied by <A HREF="#authtype">AuthType</A> and
 <A HREF="#require">Require</A> directives, and directives such as
 <A HREF="mod_auth.html#authuserfile">AuthUserFile</A> and
 <A HREF="mod_auth.html#authgroupfile">AuthGroupFile</A> to work.<P><HR>

 <H2><A NAME="authtype">AuthType directive</A></H2>
 <!--%plaintext &lt;?INDEX {\tt AuthType} directive&gt; -->
 <A
  HREF="directive-dict.html#Syntax"
  REL="Help"
 ><STRONG>Syntax:</STRONG></A> AuthType Basic|Digest<BR>
 <A
  HREF="directive-dict.html#Context"
  REL="Help"
 ><STRONG>Context:</STRONG></A> directory, .htaccess<BR>
 <A
  HREF="directive-dict.html#Override"
  REL="Help"
 ><STRONG>Override:</STRONG></A> AuthConfig<BR>
 <A
  HREF="directive-dict.html#Status"
  REL="Help"
 ><STRONG>Status:</STRONG></A> core<P>

 This directive selects the type of user authentication for a directory.
 Only <CODE>Basic</CODE> and <CODE>Digest</CODE> are currently implemented.
 <!--%plaintext &lt;?INDEX {\tt Basic} authentication scheme&gt; -->
 It must be accompanied by <A HREF="#authname">AuthName</A> and
 <A HREF="#require">Require</A> directives, and directives such as
 <A HREF="mod_auth.html#authuserfile">AuthUserFile</A> and
 <A HREF="mod_auth.html#authgroupfile">AuthGroupFile</A> to work.<P><HR>

 <H2><A NAME="clearmodulelist">ClearModuleList directive</A></H2>
 <!--%plaintext &lt;?INDEX {\tt ClearModuleList} directive&gt; -->
 <A
  HREF="directive-dict.html#Syntax"
  REL="Help"
 ><STRONG>Syntax:</STRONG></A> ClearModuleList<BR>
 <A
  HREF="directive-dict.html#Context"
  REL="Help"
 ><STRONG>Context:</STRONG></A> server config<BR>
 <A
  HREF="directive-dict.html#Status"
  REL="Help"
 ><STRONG>Status:</STRONG></A> core<BR>
 <A
  HREF="directive-dict.html#Compatibility"
  REL="Help"
 ><STRONG>Compatibility:</STRONG></A> ClearModuleList is only available in
 Apache 1.2 and later<P>

 The server comes with a built-in list of active modules.  This
 directive clears the list.  It is assumed that the list will then be
 re-populated using the <A HREF="#addmodule">AddModule</A> directive.<P><HR>

 <H2><A NAME="contentdigest">ContentDigest directive</A></H2>
 <!--%plaintext &lt;?INDEX {\tt ContentDigest} directive&gt; -->
 <A
  HREF="directive-dict.html#Syntax"
  REL="Help"
 ><STRONG>Syntax:</STRONG></A> ContentDigest on|off<BR>
 <A
  HREF="directive-dict.html#Default"
  REL="Help"
 ><STRONG>Default:</STRONG></A> <CODE>ContentDigest off</CODE><BR>
 <A
  HREF="directive-dict.html#Context"
  REL="Help"
 ><STRONG>Context:</STRONG></A> server config, virtual host, directory,
 .htaccess<BR>
 <A
  HREF="directive-dict.html#Override"
  REL="Help"
 ><STRONG>Override:</STRONG></A> Options<BR>
 <A
  HREF="directive-dict.html#Status"
  REL="Help"
 ><STRONG>Status:</STRONG></A> experimental<BR>
 <A
  HREF="directive-dict.html#Compatibility"
  REL="Help"
 ><STRONG>Compatibility:</STRONG></A> ContentDigest is only available in
 Apache 1.1 and later<P>

 This directive enables the generation of <CODE>Content-MD5</CODE> headers
 as defined in RFC1864 respectively RFC2068.<P>

 MD5 is an algorithm for computing a "message digest" (sometimes called
 "fingerprint") of arbitrary-length data, with a high degree of confidence
 that any alterations in the data will be reflected in alterations in the
 message digest.<P>

 The <CODE>Content-MD5</CODE> header provides an end-to-end message
 integrity check (MIC) of the entity-body. A proxy or client may check this
 header for detecting accidental modification of the entity-body
 in transit.
 Example header:
 <PRE>   Content-MD5: AuLb7Dp1rqtRtxz2m9kRpA==</PRE><P>

 Note that this can cause performance problems on your server
 since the message digest is computed on every request
 (the values are not cached).<P>

 <CODE>Content-MD5</CODE> is only sent for documents served by the
 core, and not by any module.  For example, SSI documents, output from
 CGI scripts, and byte range responses do not have this header.

 <HR>

 <H2><A NAME="defaulttype">DefaultType directive</A></H2>
 <!--%plaintext &lt;?INDEX {\tt DefaultType} directive&gt; -->
 <A
  HREF="directive-dict.html#Syntax"
  REL="Help"
 ><STRONG>Syntax:</STRONG></A> DefaultType <EM>MIME-type</EM><BR>
 <A
  HREF="directive-dict.html#Default"
  REL="Help"
 ><STRONG>Default:</STRONG></A> <CODE>DefaultType text/html</CODE><BR>
 <A
  HREF="directive-dict.html#Context"
  REL="Help"
 ><STRONG>Context:</STRONG></A> server config, virtual host, directory,
 .htaccess<BR>
 <A
  HREF="directive-dict.html#Override"
  REL="Help"
 ><STRONG>Override:</STRONG></A> FileInfo<BR>
 <A
  HREF="directive-dict.html#Status"
  REL="Help"
 ><STRONG>Status:</STRONG></A> core<P>

 There will be times when the server is asked to provide a document
 whose type cannot be determined by its MIME types mappings.<P>

 The server must inform the client of the content-type of the document, so in
 the event of an unknown type it uses the <CODE>DefaultType</CODE>. For
 example:
 <BLOCKQUOTE><CODE>DefaultType image/gif</CODE></BLOCKQUOTE>
 would be appropriate for a directory which contained many gif images
 with filenames missing the .gif extension.<P><HR>

 <H2><A NAME="directory">&lt;Directory&gt; directive</A></H2>
 <!--%plaintext &lt;?INDEX {\tt Directory} section directive&gt; -->
 <A
  HREF="directive-dict.html#Syntax"
  REL="Help"
 ><STRONG>Syntax:</STRONG></A> &lt;Directory <EM>directory</EM>&gt;
  ... &lt;/Directory&gt; <BR>
 <A
  HREF="directive-dict.html#Context"
  REL="Help"
 ><STRONG>Context:</STRONG></A> server config, virtual host<BR>
 <A
  HREF="directive-dict.html#Status"
  REL="Help"
 ><STRONG>Status:</STRONG></A> Core. <P>

 &lt;Directory&gt; and &lt;/Directory&gt; are used to enclose a group of
 directives which will apply only to the named directory and sub-directories
 of that directory. Any directive which is allowed in a directory
 context may be used. <EM>Directory</EM> is either the full path to a directory,
 or a wild-card string. In a wild-card string, `?' matches any single character,
 and `*' matches any sequences of characters.  As of Apache 1.3, you
 may also use `[]' character ranges like in the shell.  Also as of Apache 1.3
 none of the wildcards match a `/' character, which more closely mimics the
 behaviour of Unix shells.
 Example:
 <PRE>
    &lt;Directory /usr/local/httpd/htdocs&gt;
    Options Indexes FollowSymLinks
    &lt;/Directory&gt;
 </PRE>

 <P><STRONG>Apache 1.2 and above:</STRONG>
 Extended regular expressions can also be used, with the addition of the
 <CODE>~</CODE> character. For example:</P>

 <PRE>
    &lt;Directory ~ &quot;^/www/.*/[0-9]{3}&quot;&gt;
 </PRE>

 would match directories in /www/ that consisted of three numbers.

 <P>If multiple (non-regular expression) directory sections match the
 directory (or its parents) containing
 a document, then the directives are applied in the order of shortest match
 first, interspersed with the directives from the
 <A HREF="#accessfilename">.htaccess</A> files. For example, with
 <BLOCKQUOTE><CODE>
 &lt;Directory /&gt;<BR>
 AllowOverride None<BR>
 &lt;/Directory&gt;<BR><BR>
 &lt;Directory /home/*&gt;<BR>
 AllowOverride FileInfo<BR>
 &lt;/Directory&gt;</CODE></BLOCKQUOTE>
 for access to the document <CODE>/home/web/dir/doc.html</CODE> the
 steps are:
 <MENU>
 <LI>Apply directive <CODE>AllowOverride None</CODE> (disabling
 <CODE>.htaccess</CODE> files).
 <LI>Apply directive <CODE>AllowOverride FileInfo</CODE> (for directory
 <CODE>/home/web</CODE>).
 <LI>Apply any FileInfo directives in <CODE>/home/web/.htaccess</CODE>
 </MENU>

 <P>
 Regular expression directory sections are handled slightly differently
 by Apache 1.2 and 1.3.  In Apache 1.2 they are interspersed with the normal
 directory sections and applied in the order they appear in the configuration
 file.  They are applied only once, and apply when the shortest match
 possible occurs.  In Apache 1.3 regular expressions are not considered
 until after all of the normal sections have been applied.  Then all of
 the regular expressions are tested in the order they appeared in the
 configuration file.  For example, with
 <BLOCKQUOTE><CODE>
 &lt;Directory ~ abc$&gt;<BR>
 ... directives here ...<BR>
 &lt;/Directory&gt;<BR>
 </CODE></BLOCKQUOTE>
 Suppose that the filename being accessed is
 <CODE>/home/abc/public_html/abc/index.html</CODE>.  The server
 considers each of <CODE>/</CODE>, <CODE>/home</CODE>, <CODE>/home/abc</CODE>,
 <CODE>/home/abc/public_html</CODE>, and <CODE>/home/abc/public_html/abc</CODE>
 in that order.   In Apache 1.2, when
 <CODE>/home/abc</CODE> is considered, the regular expression will match
 and be applied.  In Apache 1.3 the regular expression isn't considered
 at all at that point in the tree.  It won't be considered until after
 all normal &lt;Directory&gt;s and <CODE>.htaccess</CODE> files have
 been applied.  Then the regular expression will
 match on <CODE>/home/abc/public_html/abc</CODE> and be applied.

 <P>

 <STRONG>
 Note that the default Apache access for &lt;Directory /&gt; is
 <SAMP>Allow from All</SAMP>.  This means that Apache will serve any file
 mapped from an URL.  It is recommended that you change this with a block
 such as
 </STRONG>
 <PRE>
  &lt;Directory /&gt;
      Order Deny,Allow
      Deny from All
  &lt;/Directory&gt;
 </PRE>
 <P>
 <STRONG>
 and then override this for directories you <EM>want</EM> accessible.
 See the
 <A
  HREF="../misc/security_tips.html"
 >Security Tips</A>
 page for more details.
 </STRONG>
 </P>

 The directory sections typically occur in the access.conf file, but they
 may appear in any configuration file. &lt;Directory&gt; directives cannot
 nest, and cannot appear in a <A HREF="#limit">&lt;Limit&gt;</A> or
 <A HREF="#limitexcept">&lt;LimitExcept&gt;</A> section.
 <P>

 <STRONG>See also</STRONG>: <A HREF="../sections.html">How Directory,
 Location and Files sections work</A> for an explanation of how these
 different sections are combined when a request is received

 <HR>

 <H2><A NAME="directorymatch">&lt;DirectoryMatch&gt;</A></H2>
 <A
  HREF="directive-dict.html#Syntax"
  REL="Help"
 ><STRONG>Syntax:</STRONG></A> &lt;DirectoryMatch <EM>regex</EM>&gt;
  ... &lt;/DirectoryMatch&gt; <BR>
 <A
  HREF="directive-dict.html#Context"
  REL="Help"
 ><STRONG>Context:</STRONG></A> server config, virtual host<BR>
 <A
  HREF="directive-dict.html#Status"
  REL="Help"
 ><STRONG>Status:</STRONG></A> Core.<BR>
 <A
  HREF="directive-dict.html#Compatibility"
  REL="Help"
 ><STRONG>Compatibility:</STRONG></A> Available in Apache 1.3 and later

 <P>&lt;DirectoryMatch&gt; and &lt;/DirectoryMatch&gt; are used to enclose a
 group of
 directives which will apply only to the named directory and sub-directories
 of that directory, the same as <A
 HREF="#directory">&lt;Directory&gt;</A>. However, it takes as an
 argument a regular expression. For example:</P>

 <PRE>
    &lt;DirectoryMatch &quot;^/www/.*/[0-9]{3}&quot;&gt;
 </PRE>

 <P>would match directories in /www/ that consisted of three numbers.</P>

 <P><STRONG>See Also:</STRONG>
 <A HREF="#directory">&lt;Directory&gt;</A> for a description of how
 regular expressions are mixed in with normal &lt;Directory&gt;s.
 <BR>
 <STRONG>See also</STRONG>: <A HREF="../sections.html">How Directory,
 Location and Files sections work</A> for an explanation of how these
 different sections are combined when a request is received

 <HR>

 <H2><A NAME="documentroot">DocumentRoot directive</A></H2>
 <!--%plaintext &lt;?INDEX {\tt DocumentRoot} directive&gt; -->
 <A
  HREF="directive-dict.html#Syntax"
  REL="Help"
 ><STRONG>Syntax:</STRONG></A> DocumentRoot <EM>directory-filename</EM><BR>
 <A
  HREF="directive-dict.html#Default"
  REL="Help"
 ><STRONG>Default:</STRONG></A> <CODE>DocumentRoot
 /usr/local/apache/htdocs</CODE><BR>
 <A
  HREF="directive-dict.html#Context"
  REL="Help"
 ><STRONG>Context:</STRONG></A> server config, virtual host<BR>
 <A
  HREF="directive-dict.html#Status"
  REL="Help"
 ><STRONG>Status:</STRONG></A> core<P>

 This directive sets the directory from which httpd will serve files.
 Unless matched by a directive like Alias, the server appends the path
 from the requested URL to the document root to make the path to the
 document. Example:
 <BLOCKQUOTE><CODE>DocumentRoot /usr/web</CODE></BLOCKQUOTE>
 then an access to <CODE>http://www.my.host.com/index.html</CODE> refers
 to <CODE>/usr/web/index.html</CODE>.

 <P>There appears to be a bug in mod_dir which causes problems when the
 DocumentRoot has a trailing slash (<EM>i.e.</EM>, "DocumentRoot /usr/web/") so
 please avoid that.

 <P><HR>

 <H2><A NAME="errordocument">ErrorDocument directive</A></H2>
 <!--%plaintext &lt;?INDEX {\tt ErrorDocument} directive&gt; -->
 <A
  HREF="directive-dict.html#Syntax"
  REL="Help"
 ><STRONG>Syntax:</STRONG></A> ErrorDocument <EM>error-code document</EM><BR>
 <A
  HREF="directive-dict.html#Context"
  REL="Help"
 ><STRONG>Context:</STRONG></A> server config, virtual host, directory,
 .htaccess<BR>
 <A
  HREF="directive-dict.html#Status"
  REL="Help"
 ><STRONG>Status:</STRONG></A> core<BR>
 <A
  HREF="directive-dict.html#Override"
  REL="Help"
 ><STRONG>Override:</STRONG></A> FileInfo<BR>
 <A
  HREF="directive-dict.html#Compatibility"
  REL="Help"
 ><STRONG>Compatibility:</STRONG></A> The directory and .htaccess contexts
 are only available in Apache 1.1 and later. The quoting syntax prior to
 Apache 2.0 was different.<P>

 In the event of a problem or error, Apache can be configured to do
 one of four things,

 <OL>
 <LI>output a simple hardcoded error message
 <LI>output a customized message
 <LI>redirect to a local URL to handle the problem/error
 <LI>redirect to an external URL to handle the problem/error
 </OL>

 <P>The first option is the default, while options 2-4 are configured
 using the <CODE>ErrorDocument</CODE> directive, which is followed by
 the HTTP response code and a URL or a message. Apache will sometimes
 offer additional information regarding the problem/error.

 <P>URLs can begin with a slash (/) for local URLs, or be a full
 URL which the client can resolve. Alternatively, a message can be
 provided to be displayed by the browser. Examples:
 <BLOCKQUOTE><CODE>
 ErrorDocument 500 http://foo.example.com/cgi-bin/tester<BR>
 ErrorDocument 404 /cgi-bin/bad_urls.pl<BR>
 ErrorDocument 401 /subscription_info.html<BR>
 ErrorDocument 403 &quot;Sorry can't allow you access today&quot;
 </CODE></BLOCKQUOTE>

 <P>Note that when you specify an <CODE>ErrorDocument</CODE> that
 points to a remote URL (ie. anything with a method such as "http" in
 front of it), Apache will send a redirect to the client to tell it
 where to find the document, even if the document ends up being on the
 same server.  This has several implications, the most important being
 that the client will not receive the original error status code, but
 instead will receive a redirect status code.  This in turn can confuse
 web robots and other clients which try to determine if a URL is valid
 using the status code.  In addition, if you use a remote URL in an
 <code>ErrorDocument 401</code>, the client will not know to prompt the
 user for a password since it will not receive the 401 status
 code. Therefore, <STRONG>if you use an "ErrorDocument 401" directive
 then it must refer to a local document.</STRONG>


 <P>Prior to version 2.0, messages were indicated by prefixing them
 with a single unmatched double quote character.

 <P>See Also: <A HREF="../custom-error.html">documentation of customizable
 responses.</A><P><HR>

 <H2><A NAME="errorlog">ErrorLog directive</A></H2>
 <!--%plaintext &lt;?INDEX {\tt ErrorLog} directive&gt; -->
 <A
  HREF="directive-dict.html#Syntax"
  REL="Help"
 ><STRONG>Syntax:</STRONG></A> ErrorLog <EM>filename</EM>|syslog[:<em>facility</em>]
 <BR>
 <A
  HREF="directive-dict.html#Default"
  REL="Help"
 ><STRONG>Default:</STRONG></A> <CODE>ErrorLog logs/error_log</CODE> (Unix)<BR>
 <A
  HREF="directive-dict.html#Default"
  REL="Help"
 ><STRONG>Default:</STRONG></A> <CODE>ErrorLog logs/error.log</CODE>
  (Windows and OS/2)<BR>
 <A
  HREF="directive-dict.html#Context"
  REL="Help"
 ><STRONG>Context:</STRONG></A> server config, virtual host<BR>
 <A
  HREF="directive-dict.html#Status"
  REL="Help"
 ><STRONG>Status:</STRONG></A> core<P>

 The error log directive sets the name of the file to which the server will log
 any errors it encounters. If the filename does not begin with a slash (/)
 then it is assumed to be relative to the <A HREF="#serverroot">ServerRoot</A>.
 If the filename begins with a pipe (|) then it is assumed to be a command to
 spawn to handle the error log.

 <P><STRONG>Apache 1.3 and above:</STRONG>
 Using <CODE>syslog</CODE> instead of a filename enables logging via syslogd(8)
 if the system supports it. The default is to use syslog facility
 <CODE>local7</CODE>, but you can override this by using the
 <CODE>syslog:</CODE><EM>facility</EM> syntax where <EM>facility</EM> can be
 one of the names usually documented in syslog(1).

 <P>
 SECURITY: See the
 <A HREF="../misc/security_tips.html#serverroot">security tips</A>
 document for details on why your security could be compromised if
 the directory where logfiles are stored is writable by anyone other
 than the user that starts the server.

 <P><STRONG>See also:</STRONG> <A HREF="#loglevel">LogLevel</A>
 <P><HR>

 <H2><A NAME="files">&lt;Files&gt; directive</A></H2>
 <A
  HREF="directive-dict.html#Syntax"
  REL="Help"
 ><STRONG>Syntax:</STRONG></A> &lt;Files <EM>filename</EM>&gt;
 ... &lt;/Files&gt;<BR>
 <A
  HREF="directive-dict.html#Context"
  REL="Help"
 ><STRONG>Context:</STRONG></A> server config, virtual host, .htaccess<BR>
 <A
  HREF="directive-dict.html#Status"
  REL="Help"
 ><STRONG>Status:</STRONG></A> core<BR>
 <A
  HREF="directive-dict.html#Compatibility"
  REL="Help"
 ><STRONG>Compatibility:</STRONG></A> only available in Apache
 1.2 and above.<P>

 <P>The &lt;Files&gt; directive provides for access control by
 filename. It is comparable to the <A
 HREF="#directory">&lt;Directory&gt;</A> directive and
 <A HREF="#location">&lt;Location&gt;</A> directives. It
 should be matched with a &lt;/Files&gt; directive.  The
 directives given within this section will be applied to any
 object with a basename (last component of filename) matching
 the specified filename.
 <CODE>&lt;Files&gt;</CODE> sections are processed in the
 order they appear in the configuration file, after the
 &lt;Directory&gt; sections and <CODE>.htaccess</CODE> files are
 read, but before &lt;Location&gt; sections.  Note that
 &lt;Files&gt; can be nested inside &lt;Directory&gt;
 sections to restrict the portion of the filesystem they
 apply to.</P>

 <P>The <EM>filename</EM> argument should include a filename, or a
 wild-card string, where `?' matches any single character, and `*' matches any
 sequences of characters. Extended regular expressions can also be used,
 with the addition of
 the <CODE>~</CODE> character. For example:</P>

 <PRE>
    &lt;Files ~ &quot;\.(gif|jpe?g|png)$&quot;&gt;
 </PRE>

 would match most common Internet graphics formats. In Apache 1.3 and
 later, <A HREF="#filesmatch">&lt;FilesMatch&gt;</A> is preferred,
 however.

 <P>Note that unlike <A
 HREF="#directory"><CODE>&lt;Directory&gt;</CODE></A> and <A
 HREF="#location"><CODE>&lt;Location&gt;</CODE></A> sections,
 <CODE>&lt;Files&gt;</CODE> sections can be used inside .htaccess
 files. This allows users to control access to their own files, at a
 file-by-file level.

 <P>

 <STRONG>See also</STRONG>: <A HREF="../sections.html">How Directory,
 Location and Files sections work</A> for an explanation of how these
 different sections are combined when a request is received

 <HR>

 <H2><A NAME="filesmatch">&lt;FilesMatch&gt;</A></H2>
 <A
  HREF="directive-dict.html#Syntax"
  REL="Help"
 ><STRONG>Syntax:</STRONG></A> &lt;FilesMatch <EM>regex</EM>&gt;
 ... &lt;/FilesMatch&gt;<BR>
 <A
  HREF="directive-dict.html#Context"
  REL="Help"
 ><STRONG>Context:</STRONG></A> server config, virtual host, .htaccess<BR>
 <A
  HREF="directive-dict.html#Status"
  REL="Help"
 ><STRONG>Status:</STRONG></A> core<BR>
 <A
  HREF="directive-dict.html#Compatibility"
  REL="Help"
 ><STRONG>Compatibility:</STRONG></A> only available in Apache
 1.3 and above.<P>

 <P>The &lt;FilesMatch&gt; directive provides for access control by
 filename, just as the <A HREF="#files">&lt;Files&gt;</A> directive
 does. However, it accepts a regular expression. For example:</P>

 <PRE>
    &lt;FilesMatch &quot;\.(gif|jpe?g|png)$&quot;&gt;
 </PRE>

 <P>would match most common Internet graphics formats.</P>

 <STRONG>See also</STRONG>: <A HREF="../sections.html">How Directory,
 Location and Files sections work</A> for an explanation of how these
 different sections are combined when a request is received

 <HR>

 <H2><A NAME="hostnamelookups">HostNameLookups directive</A></H2>
 <!--%plaintext &lt;?INDEX {\tt HostNameLookups} directive&gt; -->
 <A
  HREF="directive-dict.html#Syntax"
  REL="Help"
 ><STRONG>Syntax:</STRONG></A> HostNameLookups on|off|double<BR>
 <A
  HREF="directive-dict.html#Default"
  REL="Help"
 ><STRONG>Default:</STRONG></A> <CODE>HostNameLookups off</CODE><BR>
 <A
  HREF="directive-dict.html#Context"
  REL="Help"
 ><STRONG>Context:</STRONG></A> server config, virtual host, directory<BR>
 <A
  HREF="directive-dict.html#Status"
  REL="Help"
 ><STRONG>Status:</STRONG></A> core<BR>
 <A
  HREF="directive-dict.html#Compatibility"
  REL="Help"
 ><STRONG>Compatibility:</STRONG></A> <CODE>double</CODE> available only in
 Apache
 1.3 and above.<BR>
 <A
  HREF="directive-dict.html#Compatibility"
  REL="Help"
 ><STRONG>Compatibility:</STRONG></A> Default was <CODE>on</CODE> prior to
 Apache 1.3.<P>

 This directive enables DNS lookups so that host names can be logged (and
 passed to CGIs/SSIs in <CODE>REMOTE_HOST</CODE>).
 The value <CODE>double</CODE> refers to doing double-reverse DNS.
 That is, after a reverse lookup is performed, a forward lookup is then
 performed on that result.  At least one of the ip addresses in the forward
 lookup must match the original address.  (In "tcpwrappers" terminology
 this is called <CODE>PARANOID</CODE>.)<P>

 Regardless of the setting, when <A HREF="mod_access.html">mod_access</A>
 is used for controlling access by hostname, a double reverse lookup
 will be performed.  This is necessary for security.  Note that the
 result of this double-reverse isn't generally available unless
 you set <CODE>HostnameLookups double</CODE>.  For example, if only
 <CODE>HostnameLookups on</CODE> and a request is made to an object that
 is protected by hostname restrictions, regardless of whether the
 double-reverse fails or not, CGIs will still be passed the single-reverse
 result in <CODE>REMOTE_HOST</CODE>.<P>

 The default for this directive was previously <CODE>on</CODE> in
 versions of Apache prior to 1.3.  It was changed to <CODE>off</CODE>
 in order to save the network traffic for those sites that don't truly
 need the reverse lookups done.  It is also better for the end users
 because they don't have to suffer the extra latency that a lookup
 entails.  Heavily loaded sites should leave this directive
 <CODE>off</CODE>, since DNS lookups can take considerable amounts of
 time. The utility <a
 href="../programs/logresolve.html">logresolve</a>, provided in the
 <EM>/support</EM> directory, can be used to look up host names from
 logged IP addresses offline.<P><HR>

 <H2><A NAME="identitycheck">IdentityCheck directive</A></H2>
 <!--%plaintext &lt;?INDEX {\tt IdentityCheck} directive&gt; -->
 <A
  HREF="directive-dict.html#Syntax"
  REL="Help"
 ><STRONG>Syntax:</STRONG></A> IdentityCheck on|off<BR>
 <A
  HREF="directive-dict.html#Default"
  REL="Help"
 ><STRONG>Default:</STRONG></A> <CODE>IdentityCheck off</CODE><BR>
 <A
  HREF="directive-dict.html#Context"
  REL="Help"
 ><STRONG>Context:</STRONG></A> server config, virtual host, directory<BR>
 <A
  HREF="directive-dict.html#Status"
  REL="Help"
 ><STRONG>Status:</STRONG></A> core<P>

 This directive enables RFC1413-compliant logging of the remote user name
 for each connection, where the client machine runs identd or something similar.
 This information is logged in the access log. <EM>Boolean</EM> is either
 <CODE>on</CODE> or <CODE>off</CODE>.<P>

 The information should not be trusted in any way except for rudimentary usage
 tracking.<P>

 Note that this can cause serious latency problems accessing your server
 since every request requires one of these lookups to be performed.  When
 firewalls are involved each lookup might possibly fail and add 30 seconds
 of latency to each hit.  So in general this is not very useful on public
 servers accessible from the Internet.
 <P><HR>

 <H2><A NAME="ifdefine">&lt;IfDefine&gt; directive</A></H2>
 <A
  HREF="directive-dict.html#Syntax"
  REL="Help"
 ><STRONG>Syntax:</STRONG></A> &lt;IfDefine [!]<EM>parameter-name</EM>&gt; <EM>...</EM>
 &lt;/IfDefine&gt;<BR>
 <A
  HREF="directive-dict.html#Default"
  REL="Help"
 ><STRONG>Default:</STRONG></A> None<BR>
 <A
  HREF="directive-dict.html#Context"
  REL="Help"
 ><STRONG>Context:</STRONG></A> all<BR>
 <A
  HREF="directive-dict.html#Status"
  REL="Help"
 ><STRONG>Status:</STRONG></A> Core<BR>
 <A
  HREF="directive-dict.html#Compatibility"
  REL="Help"
 ><STRONG>Compatibility:</STRONG></A> &lt;IfDefine&gt; is only available in
 1.3.1 and later.<P>

 <P>

 The &lt;IfDefine <EM>test</EM>&gt;...&lt;/IfDefine&gt;
 section is used to mark directives that are conditional. The
 directives within an IfDefine section are only
 processed if the <EM>test</EM> is true. If <EM>test</EM>
 is false, everything between the start and end markers
 is ignored.<P>

 The <EM>test</EM> in the &lt;IfDefine&gt; section directive
 can be one of two forms:

 <UL>
 <LI><EM>parameter-name</EM>
 <LI><CODE>!</CODE><EM>parameter-name</EM>
 </UL>

 <P>In the former case, the directives between the start and end markers are
 only processed if the parameter named <EM>parameter-name</EM> is defined.
 The second format reverses the test, and only processes the directives if
 <EM>parameter-name</EM> is <STRONG>not</STRONG> defined.

 <P>The <EM>parameter-name</EM> argument is a define as given on the
 <CODE>httpd</CODE> command line via <CODE>-D</CODE><EM>parameter-</EM>, at the
 time the server was started.

 <P>&lt;IfDefine&gt; sections are nest-able, which can be used to implement
 simple multiple-parameter tests.

 Example:

 <PRE>
   $ httpd -DReverseProxy ...

   # httpd.conf
   &lt;IfDefine ReverseProxy&gt;
   LoadModule rewrite_module modules/mod_rewrite.so
   LoadModule proxy_module   modules/libproxy.so
   &lt;/IfDefine&gt;
 </PRE>

 <P> <HR>

 <H2><A NAME="ifmodule">&lt;IfModule&gt; directive</A></H2>
 <A
  HREF="directive-dict.html#Syntax"
  REL="Help"
 ><STRONG>Syntax:</STRONG></A> &lt;IfModule [!]<EM>module-name</EM>&gt;
  <EM>...</EM>
 &lt;/IfModule&gt;<BR>
 <A
  HREF="directive-dict.html#Default"
  REL="Help"
 ><STRONG>Default:</STRONG></A> None<BR>
 <A
  HREF="directive-dict.html#Context"
  REL="Help"
 ><STRONG>Context:</STRONG></A> all<BR>
 <A
  HREF="directive-dict.html#Status"
  REL="Help"
 ><STRONG>Status:</STRONG></A> Core<BR>
 <A
  HREF="directive-dict.html#Compatibility"
  REL="Help"
 ><STRONG>Compatibility:</STRONG></A> IfModule is only available in 1.2 and
 later.<P>

 <P>

 The &lt;IfModule <EM>test</EM>&gt;...&lt;/IfModule&gt;
 section is used to mark directives that are conditional. The
 directives within an IfModule section are only
 processed if the <EM>test</EM> is true. If <EM>test</EM>
 is false, everything between the start and end markers
 is ignored.<P>

 The <EM>test</EM> in the &lt;IfModule&gt; section directive
 can be one of two forms:

 <UL>
 <LI><EM>module name</EM>
 <LI>!<EM>module name</EM>
 </UL>

 <P>In the former case, the directives between the start and end markers
 are only processed if the module named <EM>module name</EM> is compiled
 in to Apache. The second format reverses the test, and only processes
 the directives if <EM>module name</EM> is <STRONG>not</STRONG> compiled in.

 <P>The <EM>module name</EM> argument is a module name as given as the file
 name of the module, at the time it was compiled. For example,
 <CODE>mod_rewrite.c</CODE>.

 <P>&lt;IfModule&gt; sections are nest-able, which can be used to implement
 simple multiple-module tests.

 <P> <HR>

 <H2><A NAME="include">Include directive</A></H2>
 <STRONG>Syntax:</STRONG> Include <EM>filename</EM><BR>
 <A
  HREF="directive-dict.html#Context"
  REL="Help"
 ><STRONG>Context:</STRONG></A> server config<BR>
 <A
  HREF="directive-dict.html#Status"
  REL="Help"
 ><STRONG>Status:</STRONG></A> Core<BR>
 <A
  HREF="directive-dict.html#Compatibility"
  REL="Help"
 ><STRONG>Compatibility:</STRONG></A> Include is only available in Apache 1.3
 and later.
 <P>
 This directive allows inclusion of other configuration files from within the
 server configuration files.

 <P>If <CODE>Include</CODE> points to a directory, rather than a file,
 Apache will read all files in that directory, and any subdirectory,
 and parse those as configuration files.

 <P> <HR>

 <H2><A NAME="keepalive">KeepAlive directive</A></H2>
 <STRONG>Syntax:</STRONG> KeepAlive on/off<BR>
 <STRONG>Default:</STRONG> <CODE>KeepAlive On</CODE><BR>
 <A
  HREF="directive-dict.html#Context"
  REL="Help"
 ><STRONG>Context:</STRONG></A> server config<BR>
 <A
  HREF="directive-dict.html#Status"
  REL="Help"
 ><STRONG>Status:</STRONG></A> Core<BR>
 <A
  HREF="directive-dict.html#Compatibility"
  REL="Help"
 ><STRONG>Compatibility:</STRONG></A> KeepAlive is only available in Apache
 1.1 and later.<P>

 <p>The Keep-Alive extension to HTTP/1.0 and the persistent connection
 feature of HTTP/1.1 provide long-lived HTTP sessions which allow
 multiple requests to be sent over the same TCP connection.  In some
 cases this has been shown to result in an almost 50% speedup in
 latency times for HTML documents with many images.  To enable
 Keep-Alive connections in Apache 1.2 and later, set <code>KeepAlive
 On</code>.</p>

 <p>For HTTP/1.0 clients, Keep-Alive connections will only be used if
 they are specifically requested by a client.  In addition, a
 Keep-Alive connection with an HTTP/1.0 client can only be used when
 the length of the content is known in advance.  This implies that
 dynamic content such as CGI output, SSI pages, and server-generated
 directory listings will generally not use Keep-Alive connections to
 HTTP/1.0 clients.  For HTTP/1.1 clients, persistent connections are
 the default unless otherwise specified.  If the client requests it,
 chunked encoding will be used in order to send content of unknown
 length over persistent connections.</p>

 <p>See also  <A
 HREF="#maxkeepaliverequests">MaxKeepAliveRequests</A>.</P>

 <HR>

 <H2><A NAME="keepalivetimeout">KeepAliveTimeout directive</A></H2>
 <A
  HREF="directive-dict.html#Syntax"
  REL="Help"
 ><STRONG>Syntax:</STRONG></A> KeepAliveTimeout <EM>seconds</EM><BR>
 <A
  HREF="directive-dict.html#Default"
  REL="Help"
 ><STRONG>Default:</STRONG></A> <CODE>KeepAliveTimeout 15</CODE><BR>
 <A
  HREF="directive-dict.html#Context"
  REL="Help"
 ><STRONG>Context:</STRONG></A> server config<BR>
 <A
  HREF="directive-dict.html#Status"
  REL="Help"
 ><STRONG>Status:</STRONG></A> Core<BR>
 <A
  HREF="directive-dict.html#Compatibility"
  REL="Help"
 ><STRONG>Compatibility:</STRONG></A> KeepAliveTimeout is only available in
 Apache 1.1 and later.<P>

 <p>The number of seconds Apache will wait for a subsequent request
 before closing the connection. Once a request has been received, the
 timeout value specified by the <A
 HREF="#timeout"><CODE>Timeout</CODE></A> directive applies.</p>

 <p>Setting <code>KeepAliveTimeout</code> to a high value may
 cause performance problems in heavily loaded servers.  The
 higher the timeout, the more server processes will be kept
 occupied waiting on connections with idle clients.</p>


 <HR>

 <H2><A NAME="limit">&lt;Limit&gt; directive</A></H2>
 <!--%plaintext &lt;?INDEX {\tt Limit} section directive&gt; -->
 <A
  HREF="directive-dict.html#Syntax"
  REL="Help"
 ><STRONG>Syntax:</STRONG></A>
  &lt;Limit <EM>method</em> [<em>method</EM>] ... &gt; ... &lt;/Limit&gt;<BR>
 <A
  HREF="directive-dict.html#Context"
  REL="Help"
 ><STRONG>Context:</STRONG></A> any<BR>
 <A
  HREF="directive-dict.html#Status"
  REL="Help"
 ><STRONG>Status:</STRONG></A> core<P>

 Access controls are normally effective for <STRONG>all</STRONG> access
 methods, and this is the usual desired behaviour.  <STRONG>In the
 general case, access control directives should not be placed within a
 <CODE>&lt;limit&gt;</CODE> section.</STRONG>

 <P>The purpose of the &lt;Limit&gt; directive is to restrict the effect
 of the access controls to the nominated HTTP methods.  For all other
 methods, the access restrictions that are enclosed in the
 &lt;Limit&gt; bracket <STRONG>will have no effect</STRONG>.  The
 following example applies the access control only to the methods POST,
 PUT, and DELETE, leaving all other methods unprotected:

 <BLOCKQUOTE><CODE>
 &lt;Limit POST PUT DELETE&gt;<BR>
 Require valid-user<BR>
 &lt;/Limit&gt;</CODE></BLOCKQUOTE>

 The method names listed can be one or more of: GET, POST, PUT, DELETE,
 CONNECT, OPTIONS, TRACE, PATCH, PROPFIND, PROPPATCH, MKCOL, COPY,
 MOVE, LOCK, and UNLOCK. <STRONG>The method name is
 case-sensitive.</STRONG> If GET is used it will also restrict HEAD
 requests.

 <P><HR>

 <H2><A NAME="limitexcept">&lt;LimitExcept&gt; directive</A></H2>
 <!--%plaintext &lt;?INDEX {\tt LimitExcept} section directive&gt; -->
 <A
  HREF="directive-dict.html#Syntax"
  REL="Help"
 ><STRONG>Syntax:</STRONG></A>
  &lt;LimitExcept <EM>method</em> [<em>method</EM>] ... &gt; ... &lt;/LimitExcept&gt;<BR>
 <A
  HREF="directive-dict.html#Context"
  REL="Help"
 ><STRONG>Context:</STRONG></A> any<BR>
 <A
  HREF="directive-dict.html#Status"
  REL="Help"
 ><STRONG>Status:</STRONG></A> core<BR>
 <A
  HREF="directive-dict.html#Compatibility"
  REL="Help"
 ><STRONG>Compatibility:</STRONG></A> Available in Apache 1.3.5 and later<P>

 &lt;LimitExcept&gt; and &lt;/LimitExcept&gt; are used to enclose a group of
 access control directives which will then apply to any HTTP access method
 <STRONG>not</STRONG> listed in the arguments; i.e., it is the opposite of a
 <A HREF="#limit">&lt;Limit&gt;</A> section and can be used to control both
 standard and nonstandard/unrecognized methods. See the documentation for
 <A HREF="#limit">&lt;Limit&gt;</A> for more details.

 <P><HR>

 <H2><A NAME="limitrequestbody">LimitRequestBody directive</A></H2>
 <!--%plaintext &lt;?INDEX {\tt LimitRequestBody} directive&gt; -->
 <A
  HREF="directive-dict.html#Syntax"
  REL="Help"
 ><STRONG>Syntax:</STRONG></A> LimitRequestBody <EM>bytes</EM><BR>
 <A
  HREF="directive-dict.html#Default"
  REL="Help"
 ><STRONG>Default:</STRONG></A> <CODE>LimitRequestBody 0</CODE><BR>
 <A
  HREF="directive-dict.html#Context"
  REL="Help"
 ><STRONG>Context:</STRONG></A> server config, virtual host, directory,
 .htaccess<BR>
 <A
  HREF="directive-dict.html#Status"
  REL="Help"
 ><STRONG>Status:</STRONG></A> core<BR>
 <A
  HREF="directive-dict.html#Compatibility"
  REL="Help"
 ><STRONG>Compatibility:</STRONG></A> LimitRequestBody is only available in
 Apache 1.3.2 and later.
 <P>

 <p>This directive specifies the number of <em>bytes</em> from 0
 (meaning unlimited) to 2147483647 (2GB) that are allowed in a request
 body.  The default value is defined by the compile-time constant
 <CODE>DEFAULT_LIMIT_REQUEST_BODY</CODE> (0 as distributed).
 <P>

 The LimitRequestBody directive allows the user to set a
 limit on the allowed size of an HTTP request message body within
 the context in which the directive is given (server, per-directory,
 per-file or per-location).  If the client request exceeds that limit,
 the server will return an error response instead of servicing the request.
 The size of a normal request message body will vary greatly depending
 on the nature of the resource and the methods allowed on that resource.
 CGI scripts typically use the message body for passing form information
 to the server.  Implementations of the PUT method will require a value
 at least as large as any representation that the server wishes
 to accept for that resource.
 <P>

 This directive gives the server administrator greater control over abnormal
 client request behavior, which may be useful for avoiding some forms
 of denial-of-service attacks.
 <P>

 <P><HR>

 <H2><A NAME="limitrequestfields">LimitRequestFields directive</A></H2>
 <!--%plaintext &lt;?INDEX {\tt LimitRequestFields} directive&gt; -->
 <A
  HREF="directive-dict.html#Syntax"
  REL="Help"
 ><STRONG>Syntax:</STRONG></A> LimitRequestFields <EM>number</EM><BR>
 <A
  HREF="directive-dict.html#Default"
  REL="Help"
 ><STRONG>Default:</STRONG></A> <CODE>LimitRequestFields 100</CODE><BR>
 <A
  HREF="directive-dict.html#Context"
  REL="Help"
 ><STRONG>Context:</STRONG></A> server config<BR>
 <A
  HREF="directive-dict.html#Status"
  REL="Help"
 ><STRONG>Status:</STRONG></A> core<BR>
 <A
  HREF="directive-dict.html#Compatibility"
  REL="Help"
 ><STRONG>Compatibility:</STRONG></A> LimitRequestFields is only available in
 Apache 1.3.2 and later.
 <P>

 <p><em>Number</em> is an integer from 0 (meaning unlimited) to 32767.
 The default value is defined by the compile-time constant
 <CODE>DEFAULT_LIMIT_REQUEST_FIELDS</CODE> (100 as distributed).
 <P>

 The LimitRequestFields directive allows the server administrator to modify
 the limit on the number of request header fields allowed in an HTTP request.
 A server needs this value to be larger than the number of fields that a
 normal client request might include.  The number of request header fields
 used by a client rarely exceeds 20, but this may vary among different
 client implementations, often depending upon the extent to which a user
 has configured their browser to support detailed content negotiation.
 Optional HTTP extensions are often expressed using request header fields.
 <P>

 This directive gives the server administrator greater control over abnormal
 client request behavior, which may be useful for avoiding some forms
 of denial-of-service attacks.  The value should be increased if normal
 clients see an error response from the server that indicates too many
 fields were sent in the request.<P>

 <P><HR>

 <H2><A NAME="limitrequestfieldsize">LimitRequestFieldsize directive</A></H2>
 <!--%plaintext &lt;?INDEX {\tt LimitRequestFieldsize} directive&gt; -->
 <A
  HREF="directive-dict.html#Syntax"
  REL="Help"
 ><STRONG>Syntax:</STRONG></A> LimitRequestFieldsize <EM>bytes</EM><BR>
 <A
  HREF="directive-dict.html#Default"
  REL="Help"
 ><STRONG>Default:</STRONG></A> <CODE>LimitRequestFieldsize 8190</CODE><BR>
 <A
  HREF="directive-dict.html#Context"
  REL="Help"
 ><STRONG>Context:</STRONG></A> server config<BR>
 <A
  HREF="directive-dict.html#Status"
  REL="Help"
 ><STRONG>Status:</STRONG></A> core<BR>
 <A
  HREF="directive-dict.html#Compatibility"
  REL="Help"
 ><STRONG>Compatibility:</STRONG></A> LimitRequestFieldsize is only available in
 Apache 1.3.2 and later.
 <P>

 This directive specifies the number of <em>bytes</em> from 0 to the
 value of the compile-time constant
 <CODE>DEFAULT_LIMIT_REQUEST_FIELDSIZE</CODE> (8190 as distributed)
 that will be allowed in an HTTP request header.
 <P>

 The LimitRequestFieldsize directive allows the server administrator to reduce
 the limit on the allowed size of an HTTP request header field below the
 normal input buffer size compiled with the server.  A server needs this
 value to be large enough to hold any one header field from a normal client
 request.  The size of a normal request header field will vary greatly
 among different client implementations, often depending upon the extent
 to which a user has configured their browser to support detailed
 content negotiation.
 <P>

 This directive gives the server administrator greater control over abnormal
 client request behavior, which may be useful for avoiding some forms
 of denial-of-service attacks.  Under normal conditions, the value should
 not be changed from the default.<P>

 <P><HR>

 <H2><A NAME="limitrequestline">LimitRequestLine directive</A></H2>
 <!--%plaintext &lt;?INDEX {\tt LimitRequestLine} directive&gt; -->
 <A
  HREF="directive-dict.html#Syntax"
  REL="Help"
 ><STRONG>Syntax:</STRONG></A> LimitRequestLine <EM>bytes</EM><BR>
 <A
  HREF="directive-dict.html#Default"
  REL="Help"
 ><STRONG>Default:</STRONG></A> <CODE>LimitRequestLine 8190</CODE><BR>
 <A
  HREF="directive-dict.html#Context"
  REL="Help"
 ><STRONG>Context:</STRONG></A> server config<BR>
 <A
  HREF="directive-dict.html#Status"
  REL="Help"
 ><STRONG>Status:</STRONG></A> core<BR>
 <A
  HREF="directive-dict.html#Compatibility"
  REL="Help"
 ><STRONG>Compatibility:</STRONG></A> LimitRequestLine is only available in
 Apache 1.3.2 and later.
 <P>

 This directive sets the number of <em>bytes</em> from 0 to the value
 of the compile-time constant <CODE>DEFAULT_LIMIT_REQUEST_LINE</CODE>
 (8190 as distributed) that will be allowed on the HTTP request-line.
 <P>

 The LimitRequestLine directive allows the server administrator to reduce
 the limit on the allowed size of a client's HTTP request-line below the
 normal input buffer size compiled with the server.  Since the request-line
 consists of the HTTP method, URI, and protocol version, the
 LimitRequestLine directive places a restriction on the length of a
 request-URI allowed for a request on the server.  A server needs this
 value to be large enough to hold any of its resource names, including
 any information that might be passed in the query part of a GET request.
 <P>

 This directive gives the server administrator greater control over abnormal
 client request behavior, which may be useful for avoiding some forms
 of denial-of-service attacks.  Under normal conditions, the value should
 not be changed from the default.<P>

 <P><HR>


 <H2><A NAME="limitxmlrequestbody">LimitXMLRequestBody directive</A></H2>
 <A
  HREF="directive-dict.html#Syntax"
  REL="Help"
 ><STRONG>Syntax:</STRONG></A> LimitXMLRequestBody <EM>number</EM><BR>
 <A
  HREF="directive-dict.html#Default"
  REL="Help"
 ><STRONG>Default:</STRONG></A> <CODE>LimitXMLRequestBody 1000000</CODE><BR>
 <A
  HREF="directive-dict.html#Context"
  REL="Help"
 ><STRONG>Context:</STRONG></A> server config<BR>
 <A
  HREF="directive-dict.html#Status"
  REL="Help"
 ><STRONG>Status:</STRONG></A> core<BR>

 <P>Limit (in bytes) on maximum size of an XML-based request body.</p>

 <P><HR>

 <H2><A NAME="location">&lt;Location&gt; directive</A></H2>

 <A
  HREF="directive-dict.html#Syntax"
  REL="Help"
 ><STRONG>Syntax:</STRONG></A> &lt;Location <EM>URL</EM>&gt;
 ... &lt;/Location&gt;<BR>
 <A
  HREF="directive-dict.html#Context"
  REL="Help"
 ><STRONG>Context:</STRONG></A> server config, virtual host<BR>
 <A
  HREF="directive-dict.html#Status"
  REL="Help"
 ><STRONG>Status:</STRONG></A> core<BR>
 <A
  HREF="directive-dict.html#Compatibility"
  REL="Help"
 ><STRONG>Compatibility:</STRONG></A> Location is only available in Apache
 1.1 and later.<P>

 <P>The &lt;Location&gt; directive provides for access control by
 URL. It is similar to the <A
 HREF="#directory">&lt;Directory&gt;</A> directive, and
 starts a subsection which is terminated with a &lt;/Location&gt;
 directive.  <CODE>&lt;Location&gt;</CODE> sections are processed in the
 order they appear in the configuration file, after the
 &lt;Directory&gt; sections and <CODE>.htaccess</CODE> files are
 read, and after the &lt;Files&gt; sections.</P>

 <P>Note that URLs do not have to line up with the filesystem at all,
 it should be emphasized that &lt;Location&gt; operates completely outside
 the filesystem.

 <P>For all origin (non-proxy) requests, the URL to be matched is
 of the form <CODE>/path/</CODE>, and you should not include any
 <CODE>http://servername</CODE> prefix.  For proxy requests, the URL
 to be matched is of the form <CODE>scheme://servername/path</CODE>,
 and you must include the prefix.

 <P>The URL may use wildcards In a wild-card string, `?' matches any
 single character, and `*' matches any sequences of characters.

 <P><STRONG>Apache 1.2 and above:</STRONG>
 Extended regular expressions can also be used, with the addition of
 the <CODE>~</CODE> character.

 For example:</P>

 <PRE>
    &lt;Location ~ &quot;/(extra|special)/data&quot;&gt;
 </PRE>

 <P>would match URLs that contained the substring "/extra/data" or
 "/special/data".  In Apache 1.3 and above, a new directive
 <A HREF="#locationmatch">&lt;LocationMatch&gt;</A> exists which
 behaves identical to the regex version of
 <CODE>&lt;Location&gt;</CODE>.

 <P>The <CODE>Location</CODE> functionality is especially useful when
 combined with the <CODE><A
 HREF="mod_mime.html#sethandler">SetHandler</A></CODE> directive. For example,
 to enable status requests, but allow them only
 from browsers at foo.com, you might use:

 <PRE>
     &lt;Location /status&gt;
     SetHandler server-status
     Order Deny,Allow
     Deny from all
     Allow from .foo.com
     &lt;/Location&gt;
 </PRE>

 <P><STRONG>Apache 1.3 and above note about / (slash)</STRONG>:  The slash
 character has special
 meaning depending on where in a URL it appears.  People may be used
 to its behaviour in the filesystem where multiple adjacent slashes are
 frequently collapsed to a single slash (<EM>i.e.</EM>, <CODE>/home///foo</CODE>
 is the same as <CODE>/home/foo</CODE>).  In URL-space this is not
 necessarily true.  The <CODE>&lt;LocationMatch&gt;</CODE> directive
 and the regex version of <CODE>&lt;Location&gt;</CODE> require you
 to explicitly specify multiple slashes if that is your intention.
 For example, <CODE>&lt;LocationMatch ^/abc&gt;</CODE> would match the
 request URL <CODE>/abc</CODE> but not the request URL <CODE>//abc</CODE>.
 The (non-regex) <CODE>&lt;Location&gt;</CODE> directive behaves
 similarly when used for proxy requests.  But when (non-regex)
 <CODE>&lt;Location&gt;</CODE> is used for non-proxy requests it will
 implicitly match multiple slashes with a single slash.  For example,
 if you specify <CODE>&lt;Location /abc/def&gt;</CODE> and the request
 is to <CODE>/abc//def</CODE> then it will match.

 <P>
 <STRONG>See also</STRONG>: <A HREF="../sections.html">How Directory,
 Location and Files sections work</A> for an explanation of how these
 different sections are combined when a request is received

 <HR>

 <H2><A NAME="locationmatch">&lt;LocationMatch&gt;</A></H2>

 <A
  HREF="directive-dict.html#Syntax"
  REL="Help"
 ><STRONG>Syntax:</STRONG></A> &lt;LocationMatch <EM>regex</EM>&gt;
 ... &lt;/LocationMatch&gt;<BR>
 <A
  HREF="directive-dict.html#Context"
  REL="Help"
 ><STRONG>Context:</STRONG></A> server config, virtual host<BR>
 <A
  HREF="directive-dict.html#Status"
  REL="Help"
 ><STRONG>Status:</STRONG></A> core<BR>
 <A
  HREF="directive-dict.html#Compatibility"
  REL="Help"
 ><STRONG>Compatibility:</STRONG></A> LocationMatch is only available in
 Apache 1.3 and later.<P>

 <P>The &lt;LocationMatch&gt; directive provides for access control by
 URL, in an identical manner to <A
 HREF="#location">&lt;Location&gt;</A>. However, it takes a regular
 expression as an argument instead of a simple string. For example:</P>

 <PRE>
    &lt;LocationMatch &quot;/(extra|special)/data&quot;&gt;
 </PRE>

 <P>would match URLs that contained the substring "/extra/data" or
 "/special/data".</P>

 <STRONG>See also</STRONG>: <A HREF="../sections.html">How Directory,
 Location and Files sections work</A> for an explanation of how these
 different sections are combined when a request is received

 <HR>

 <H2><A NAME="loglevel">LogLevel directive</A></H2>
 <A
  HREF="directive-dict.html#Syntax"
  REL="Help"
 ><STRONG>Syntax:</STRONG></A> LogLevel <EM>level</EM><BR>
 <A
  HREF="directive-dict.html#Default"
  REL="Help"
 ><STRONG>Default:</STRONG></A> <CODE>LogLevel error</CODE><BR>
 <A
  HREF="directive-dict.html#Context"
  REL="Help"
 ><STRONG>Context:</STRONG></A> server config, virtual host<BR>
 <A
  HREF="directive-dict.html#Status"
  REL="Help"
 ><STRONG>Status:</STRONG></A> core<BR>
 <A
  HREF="directive-dict.html#Compatibility"
  REL="Help"
 ><STRONG>Compatibility:</STRONG></A> LogLevel is only available in 1.3 or
 later.

 <P>LogLevel adjusts the verbosity of the messages recorded in the
 error logs (see <A HREF="#errorlog">ErrorLog</A> directive).
 The following <EM>level</EM>s are available, in order of
 decreasing significance:

 <P><TABLE>
   <TR><TH ALIGN="LEFT"><STRONG>Level</STRONG>
       <TH ALIGN="LEFT"><STRONG>Description</STRONG>
   <TR><TH><TH ALIGN="LEFT"><STRONG>Example</STRONG>
   <TR><TD><CODE>emerg</CODE>
       <TD>Emergencies - system is unusable.
   <TR><TD><TD>"Child cannot open lock file.  Exiting"
   <TR><TD><CODE>alert</CODE>
       <TD>Action must be taken immediately.
   <TR><TD><TD>"getpwuid: couldn't determine user name from uid"
   <TR><TD><CODE>crit</CODE>
       <TD>Critical Conditions.
   <TR><TD><TD>"socket: Failed to get a socket, exiting child"
   <TR><TD><CODE>error</CODE>
       <TD>Error conditions.
   <TR><TD><TD>"Premature end of script headers"
   <TR><TD><CODE>warn</CODE>
       <TD>Warning conditions.
   <TR><TD><TD>"child process 1234 did not exit, sending another SIGHUP"
   <TR><TD><CODE>notice</CODE>
       <TD>Normal but significant condition.
   <TR><TD><TD>"httpd: caught SIGBUS, attempting to dump core in ..."
   <TR><TD><CODE>info</CODE>
       <TD>Informational.
   <TR><TD><TD>"Server seems busy, (you may need to increase StartServers, or
               Min/MaxSpareServers)..."
   <TR><TD><CODE>debug</CODE>
       <TD>Debug-level messages
   <TR><TD><TD>"Opening config file ..."
 </TABLE>

 <P>When a particular level is specified, messages from all other levels
 of higher significance will be reported as well.  <EM>E.g.</EM>, when
 <CODE>LogLevel info</CODE> is specified, then messages with log levels of
 <CODE>notice</CODE> and <CODE>warn</CODE> will also be posted.
 <P>
 Using a level of at least <CODE>crit</CODE> is recommended.
 <P><HR>

 <H2><A NAME="maxkeepaliverequests">MaxKeepAliveRequests directive</A></H2>
 <A
  HREF="directive-dict.html#Syntax"
  REL="Help"
 ><STRONG>Syntax:</STRONG></A> MaxKeepAliveRequests <EM>number</EM><BR>
 <A
  HREF="directive-dict.html#Default"
  REL="Help"
 ><STRONG>Default:</STRONG></A> <CODE>MaxKeepAliveRequests 100</CODE><BR>
 <A
  HREF="directive-dict.html#Context"
  REL="Help"
 ><STRONG>Context:</STRONG></A> server config<BR>
 <A
  HREF="directive-dict.html#Status"
  REL="Help"
 ><STRONG>Status:</STRONG></A> core<BR>
 <A
  HREF="directive-dict.html#Compatibility"
  REL="Help"
 ><STRONG>Compatibility:</STRONG></A> Only available in Apache
 1.2 and later.

 <P>The MaxKeepAliveRequests directive limits the number of requests
 allowed per connection when <A HREF="#keepalive">KeepAlive</A> is
 on. If it is set to "<CODE>0</CODE>", unlimited requests will be
 allowed. We recommend that this setting be kept to a high value for
 maximum server performance.</P><HR>

 <H2><A NAME="namevirtualhost">NameVirtualHost directive</A></H2>
 <!--%plaintext &lt;?INDEX {\tt NameVirtualHost} directive&gt; -->
 <A
  HREF="directive-dict.html#Syntax"
  REL="Help"
 ><STRONG>Syntax:</STRONG></A> NameVirtualHost <EM>addr</EM>[:<EM>port</EM>]<BR>
 <A
  HREF="directive-dict.html#Context"
  REL="Help"
 ><STRONG>Context:</STRONG></A> server config<BR>
 <A
  HREF="directive-dict.html#Status"
  REL="Help"
 ><STRONG>Status:</STRONG></A> core<BR>
 <A
  HREF="directive-dict.html#Compatibility"
  REL="Help"
 ><STRONG>Compatibility:</STRONG></A> NameVirtualHost is only available in
 Apache 1.3 and later<P>

 The NameVirtualHost directive is a required directive if you want to configure
 <A HREF="../vhosts/">name-based virtual hosts</A>.<P>

 Although <EM>addr</EM> can be hostname it is recommended that you always use
 an IP address, <EM>e.g.</EM>

 <BLOCKQUOTE><CODE>NameVirtualHost 111.22.33.44</CODE></BLOCKQUOTE>

 With the NameVirtualHost directive you specify the IP address on which
 the server will receive requests for the name-based virtual hosts.
 This will usually be the address to which your name-based virtual host
 names resolve. In cases where a firewall or other proxy receives the
 requests and forwards them on a different IP address to the server,
 you must specify the IP address of the physical interface on the
 machine which will be servicing the requests.  If you have multiple
 name-based hosts on multiple addresses, repeat the directive for each
 address.<P>

 Note: the "main server" and any _default_ servers will <STRONG>never</STRONG>
 be served for a request to a NameVirtualHost IP Address (unless for some
 reason you specify NameVirtualHost but then don't define any VirtualHosts
 for that address).<P>

 Optionally you can specify a port number on which the name-based
 virtual hosts should be used, <EM>e.g.</EM>

 <BLOCKQUOTE><CODE>NameVirtualHost 111.22.33.44:8080</CODE></BLOCKQUOTE>

 <STRONG>See also:</STRONG>
 <A HREF="../vhosts/">Apache Virtual Host documentation</A>
 <HR>

 <H2><A NAME="options">Options directive</A></H2>
 <!--%plaintext &lt;?INDEX {\tt Options} directive&gt; -->
 <A
  HREF="directive-dict.html#Syntax"
  REL="Help"
 ><STRONG>Syntax:</STRONG></A> Options [+|-]<em>option</em> [[+|-]<em>option</em>] ...</EM><BR>
 <A
  HREF="directive-dict.html#Context"
  REL="Help"
 ><STRONG>Context:</STRONG></A> server config, virtual host, directory,
 .htaccess<BR>
 <A
  HREF="directive-dict.html#Override"
  REL="Help"
 ><STRONG>Override:</STRONG></A> Options<BR>
 <A
  HREF="directive-dict.html#Status"
  REL="Help"
 ><STRONG>Status:</STRONG></A> core<P>

 The Options directive controls which server features are available in
 a particular directory.
 <P>
 <EM>option</EM> can be set to <CODE>None</CODE>, in which case none of
 the extra features are enabled, or one or more of the following:
 <DL>
 <DT>All
 <DD>All options except for MultiViews. This is the default setting.
 <DT>ExecCGI
 <DD>
 <!--%plaintext &lt;?INDEX {\tt ExecCGI} option&gt; -->
 Execution of CGI scripts is permitted.
 <DT>FollowSymLinks
 <DD>
 <!--%plaintext &lt;?INDEX {\tt FollowSymLinks} option&gt; -->
 The server will follow symbolic links in this directory.
 <BR>
 <STRONG>Note</STRONG>: even though the server follows the symlink it
 does <EM>not</EM>
 change the pathname used to match against <CODE>&lt;Directory&gt;</CODE>
 sections.
 <BR>
 <STRONG>Note</STRONG>: this option gets ignored if set inside a
 &lt;Location&gt; section.

 <DT>Includes
 <DD>
 <!--%plaintext &lt;?INDEX {\tt Includes} option&gt; -->
 Server-side includes are permitted.
 <DT>IncludesNOEXEC
 <DD>
 <!--%plaintext &lt;?INDEX {\tt IncludesNOEXEC} option&gt; -->
 Server-side includes are permitted, but the #exec command and
 #include of CGI scripts are disabled.
 <DT>Indexes
 <DD>
 <!--%plaintext &lt;?INDEX {\tt Indexes} option&gt; -->
 If a URL which maps to a directory is requested, and the there is no
 DirectoryIndex (<EM>e.g.</EM>, index.html) in that directory, then the server will
 return a formatted listing of the directory.
 <DT>MultiViews
 <DD>
 <!--%plaintext &lt;?INDEX {\tt MultiViews} option&gt; -->
 <A HREF="../content-negotiation.html">Content negotiated</A> MultiViews are
 allowed.
 <DT>SymLinksIfOwnerMatch
 <DD>
 <!--%plaintext &lt;?INDEX {\tt SymLinksIfOwnerMatch} option&gt; -->
 The server will only follow symbolic links for which the target
 file or directory is owned by the same user id as the link.
 <BR>
 <STRONG>Note</STRONG>: this option gets ignored if set inside a
 &lt;Location&gt; section.
 </DL>

 Normally, if multiple <CODE>Options</CODE> could apply to a directory,
 then the most specific one is taken complete; the options are not
 merged. However if <EM>all</EM> the options on the <CODE>Options</CODE>
 directive are preceded by a + or - symbol, the options are
 merged. Any options preceded by a + are added to the options
 currently in force, and any options preceded by a - are removed from
 the options currently in force.  <P>

 For example, without any + and - symbols:

 <BLOCKQUOTE><CODE>
 &lt;Directory /web/docs&gt; <BR>
 Options Indexes FollowSymLinks<BR>
 &lt;/Directory&gt;<BR>
 &lt;Directory /web/docs/spec&gt; <BR>
 Options Includes<BR>
 &lt;/Directory&gt;
 </CODE></BLOCKQUOTE>
 then only <CODE>Includes</CODE> will be set for the /web/docs/spec
 directory. However if the second <CODE>Options</CODE> directive uses the +
 and - symbols:<P>

 <BLOCKQUOTE><CODE>
 &lt;Directory /web/docs&gt; <BR>
 Options Indexes FollowSymLinks<BR>
 &lt;/Directory&gt;<BR>
 &lt;Directory /web/docs/spec&gt; <BR>
 Options +Includes -Indexes<BR>
 &lt;/Directory&gt;
 </CODE></BLOCKQUOTE>
 then the options <CODE>FollowSymLinks</CODE> and <CODE>Includes</CODE>
 are set for the /web/docs/spec directory.<P>

 <STRONG>Note:</STRONG> Using <CODE>-IncludesNOEXEC</CODE> or
 <CODE>-Includes</CODE>
 disables server-side includes completely regardless of the previous setting.<P>

 The default in the absence of any other settings is <CODE>All</CODE>.<P>
 <HR>


 <H2><A NAME="port">Port directive</A></H2>
 <!--%plaintext &lt;?INDEX {\tt Port} directive&gt; -->
 <A
  HREF="directive-dict.html#Syntax"
  REL="Help"
 ><STRONG>Syntax:</STRONG></A> Port <EM>number</EM><BR>
 <A
  HREF="directive-dict.html#Default"
  REL="Help"
 ><STRONG>Default:</STRONG></A> <CODE>Port 80</CODE><BR>
 <A
  HREF="directive-dict.html#Context"
  REL="Help"
 ><STRONG>Context:</STRONG></A> server config<BR>
 <A
  HREF="directive-dict.html#Status"
  REL="Help"
 ><STRONG>Status:</STRONG></A> core<P>

 <EM>Number</EM> is a number from 0 to 65535; some port numbers
 (especially below
 1024) are reserved for particular protocols. See <CODE>/etc/services</CODE>
 for a list of some defined ports; the standard port for the http protocol
 is 80.<P>

 The Port directive has two behaviors, the first of which is necessary for
 NCSA backwards compatibility (and which is confusing in the context of
 Apache).<P>

 <UL>
 <LI>
 In the absence of any <A HREF="mpm_common.html#listen">Listen</A>
 directives specifying a port number,
 a Port directive given in the "main server"
 (<EM>i.e.</EM>, outside any <A HREF="#virtualhost">&lt;VirtualHost&gt</A> section)
 sets the network port on which the server listens.
 If there are any Listen directives specifying
 <CODE>:number</CODE> then Port has no effect on what address the server
 listens at.

 <LI>The Port directive
 sets the <CODE>SERVER_PORT</CODE> environment variable (for
 <A HREF="mod_cgi.html">CGI</A> and <A HREF="mod_include.html">SSI</A>),
 and is used when the server must generate a URL that refers to itself
 (for example when creating an external redirect to itself).  This
 behaviour is modified by
 <A HREF="#usecanonicalname">UseCanonicalName</A>.
 </UL>

 In no event does a Port setting affect
 what ports a <A HREF="#virtualhost">VirtualHost</A> responds on, the
 VirtualHost directive itself is used for that.<P>

 The primary behaviour of Port should be considered to be similar to that of
 the <A HREF="#servername">ServerName</A> directive.  The ServerName
 and Port together specify what you consider to be the <EM>canonical</EM>
 address of the server.
 (See also <A HREF="#usecanonicalname">UseCanonicalName</A>.)<P>

 Port 80 is one of Unix's special ports. All ports numbered below 1024
 are reserved for system use, <EM>i.e.</EM>, regular (non-root) users
 cannot make use of them; instead they can only use higher port
 numbers.  To use port 80, you must start the server from the root
 account.  After binding to the port and before accepting requests,
 Apache will change to a low privileged user as set by the <A
 HREF="mpm_common.html#user">User directive</A>.<P>

 If you cannot use port 80, choose any other unused port. Non-root users
 will have to choose a port number higher than 1023, such as 8000.<P>

 SECURITY: if you do start the server as root, be sure not to set <A
 HREF="mpm_common.html#user">User</A> to root. If you run the server as
 root whilst handling connections, your site may be open to a major
 security attack.<P><HR>

 <H2><A NAME="require">Require directive</A></H2>
 <!--%plaintext &lt;?INDEX {\tt Require} directive&gt; -->
 <A
  HREF="directive-dict.html#Syntax"
  REL="Help"
 ><STRONG>Syntax:</STRONG></A> Require <EM>entity-name</em> [<em>entity-name</em>] ...</EM><BR>
 <A
  HREF="directive-dict.html#Context"
  REL="Help"
 ><STRONG>Context:</STRONG></A> directory, .htaccess<BR>
 <A
  HREF="directive-dict.html#Override"
  REL="Help"
 ><STRONG>Override:</STRONG></A> AuthConfig<BR>
 <A
  HREF="directive-dict.html#Status"
  REL="Help"
 ><STRONG>Status:</STRONG></A> core<P>

 This directive selects which authenticated users can access a directory.
 The allowed syntaxes are:
 <UL>
 <LI>Require user <EM>userid</em> [<em>userid</em>] ...<P>
 Only the named users can access the directory.<P>
 <LI>Require group <EM>group-name</em> [<em>group-name</em>] ...<P>
 Only users in the named groups can access the directory.<P>
 <LI>Require valid-user<P>
 All valid users can access the directory.
 </UL>
 <P>
 Require must be accompanied by <A HREF="#authname">AuthName</A> and
 <A HREF="#authtype">AuthType</A> directives, and directives such as
 <A HREF="mod_auth.html#authuserfile">AuthUserFile</A> and
 <A HREF="mod_auth.html#authgroupfile">AuthGroupFile</A> (to define users and
 groups) in order to work correctly.  Example:
 <BLOCKQUOTE><CODE>
 AuthType Basic<BR>
 AuthName "Restricted Directory"<BR>
 AuthUserFile /web/users<BR>
 AuthGroupFile /web/groups<BR>
 Require group admin<BR>
 </CODE></BLOCKQUOTE>

 Access controls which are applied in this way are effective for
 <STRONG>all</STRONG> methods. <STRONG>This is what is normally
 desired.</STRONG> If you wish to apply access controls only to
 specific methods, while leaving other methods unprotected, then place
 the <CODE>Require</CODE> statement into a <A
 HREF="#limit">&lt;Limit&gt;</A> section<P>
 <P>See also <A HREF="#satisfy">Satisfy</A> and <A HREF="mod_access.html">mod_access</A>.
 <HR>

 <H2><A NAME="rlimit">RLimitCPU</A> <A NAME="rlimitcpu">directive</A></H2>
 <!--%plaintext &lt;?INDEX {\tt RLimitCPU} directive&gt; -->
 <A
  HREF="directive-dict.html#Syntax"
  REL="Help"
 ><STRONG>Syntax:</STRONG></A> RLimitCPU <EM>number</EM>|max
  [<em>number</em>|max]
 <BR>
 <A
  HREF="directive-dict.html#Default"
  REL="Help"
 ><STRONG>Default:</STRONG></A> <EM>Unset; uses operating system defaults</EM>
 <BR>
 <A
  HREF="directive-dict.html#Context"
  REL="Help"
 ><STRONG>Context:</STRONG></A> server config, virtual host<BR>
 <A
  HREF="directive-dict.html#Status"
  REL="Help"
 ><STRONG>Status:</STRONG></A> core<BR>
 <A
  HREF="directive-dict.html#Compatibility"
  REL="Help"
 ><STRONG>Compatibility:</STRONG></A> RLimitCPU is only available in Apache 1.2
 and later. Moved in version 2.0 to the <A HREF="../mpm.html">MPMs</A>.<P>

 Takes 1 or 2 parameters. The first parameter sets the soft resource limit
 for all processes and the second parameter sets the maximum resource limit.
 Either parameter can be a number, or <EM>max</EM> to indicate to the server
 that the limit should be set to the maximum allowed by the operating system
 configuration. Raising the maximum resource limit requires that the server
 is running as root, or in the initial startup phase.<P>

 This applies to processes forked off from Apache children servicing requests,
 not the Apache children themselves. This includes CGI scripts and SSI
 exec commands, but not any processes forked off from the Apache parent
 such as piped logs.<P>

 CPU resource limits are expressed in seconds per process.<P>

 See also <A HREF="#rlimitmem">RLimitMEM</A> or
 <A HREF="#rlimitnproc">RLimitNPROC</A>.<P><HR>

 <H2><A NAME="rlimitmem">RLimitMEM directive</A></H2>
 <!--%plaintext &lt;?INDEX {\tt RLimitMEM} directive&gt; -->
 <A
  HREF="directive-dict.html#Syntax"
  REL="Help"
 ><STRONG>Syntax:</STRONG></A> RLimitMEM <em>number</em>|max
   [<em>number</em>|max]<br>
 <A
  HREF="directive-dict.html#Default"
  REL="Help"
 ><STRONG>Default:</STRONG></A> <EM>Unset; uses operating system defaults</EM>
 <BR>
 <A
  HREF="directive-dict.html#Context"
  REL="Help"
 ><STRONG>Context:</STRONG></A> server config, virtual host<BR>
 <A
  HREF="directive-dict.html#Status"
  REL="Help"
 ><STRONG>Status:</STRONG></A> core<BR>
 <A
  HREF="directive-dict.html#Compatibility"
  REL="Help"
 ><STRONG>Compatibility:</STRONG></A> RLimitMEM is only available in Apache 1.2
 and later. Moved in version 2.0 to the <A HREF="../mpm.html">MPMs</A>.<P>

 Takes 1 or 2 parameters. The first parameter sets the soft resource limit for
 all processes and the second parameter sets the maximum resource limit. Either
 parameter can be a number, or <EM>max</EM> to indicate to the server that the
 limit should be set to the maximum allowed by the operating system
 configuration. Raising the maximum resource limit requires that the
 server is running as root, or in the initial startup phase.<P>

 This applies to processes forked off from Apache children servicing requests,
 not the Apache children themselves. This includes CGI scripts and SSI
 exec commands, but not any processes forked off from the Apache parent
 such as piped logs.<P>

 Memory resource limits are expressed in bytes per process.<P>

 See also <A HREF="#rlimitcpu">RLimitCPU</A> or
 <A HREF="#rlimitnproc">RLimitNPROC</A>.<P><HR>

 <H2><A NAME="rlimitnproc">RLimitNPROC directive</A></H2>
 <!--%plaintext &lt;?INDEX {\tt RLimitNPROC} directive&gt; -->
 <A
  HREF="directive-dict.html#Syntax"
  REL="Help"
 ><STRONG>Syntax:</STRONG></A> RLimitNPROC <em>number</em>|max
  [<em>number</em>|max]<BR>
 <A
  HREF="directive-dict.html#Default"
  REL="Help"
 ><STRONG>Default:</STRONG></A> <EM>Unset; uses operating system defaults</EM>
 <BR>
 <A
  HREF="directive-dict.html#Context"
  REL="Help"
 ><STRONG>Context:</STRONG></A> server config, virtual host<BR>
 <A
  HREF="directive-dict.html#Status"
  REL="Help"
 ><STRONG>Status:</STRONG></A> core<BR>
 <A
  HREF="directive-dict.html#Compatibility"
  REL="Help"
 ><STRONG>Compatibility:</STRONG></A> RLimitNPROC is only available in Apache
 1.2 and later. Moved in version 2.0 to the <A HREF="../mpm.html">MPMs</A>.<P>

 Takes 1 or 2 parameters. The first parameter sets the soft resource limit
 for all processes and the second parameter sets the maximum resource limit.
 Either parameter can be a number, or <code>max</code> to indicate to the server
 that the limit should be set to the maximum allowed by the operating system
 configuration. Raising the maximum resource limit requires that the server
 is running as root, or in the initial startup phase.<P>

 This applies to processes forked off from Apache children servicing requests,
 not the Apache children themselves. This includes CGI scripts and SSI
 exec commands, but not any processes forked off from the Apache parent
 such as piped logs.<P>

 Process limits control the number of processes per user.<P>

 Note: If CGI processes are <STRONG>not</STRONG> running under userids other
 than the
 web server userid, this directive will limit the number of processes that the
 server itself can create. Evidence of this situation will be indicated by
 <STRONG><EM>cannot fork</EM></STRONG> messages in the error_log.<P>

 See also <A HREF="#rlimitmem">RLimitMEM</A> or
 <A HREF="#rlimitcpu">RLimitCPU</A>.

 <P><HR>

 <H2><A NAME="satisfy">Satisfy directive</A></H2>
 <!--%plaintext &lt;?INDEX {\tt Satisfy} directive&gt; -->
 <A
  HREF="directive-dict.html#Syntax"
  REL="Help"
 ><STRONG>Syntax:</STRONG></A> Satisfy any|all<BR>
 <A
  HREF="directive-dict.html#Default"
  REL="Help"
 ><STRONG>Default:</STRONG></A> Satisfy all<BR>
 <A
  HREF="directive-dict.html#Context"
  REL="Help"
 ><STRONG>Context:</STRONG></A> directory, .htaccess<BR>
 <A
  HREF="directive-dict.html#Status"
  REL="Help"
 ><STRONG>Status:</STRONG></A> core<BR>
 <A
  HREF="directive-dict.html#Compatibility"
  REL="Help"
 ><STRONG>Compatibility:</STRONG></A> Satisfy is only available in Apache 1.2
 and later<P>

 Access policy if both <CODE>Allow</CODE> and <CODE>Require</CODE>
 used. The parameter can be
 either <EM>'all'</EM> or <EM>'any'</EM>. This directive is only useful
 if access to a particular area is being restricted by both
 username/password <EM>and</EM> client host address. In this case the
 default behavior ("all") is to require that the client passes the
 address access restriction <EM>and</EM> enters a valid username and
 password. With the "any" option the client will be granted access if
 they either pass the host restriction or enter a valid username and
 password. This can be used to password restrict an area, but to let
 clients from particular addresses in without prompting for a password.
 <P>
 See also <A HREF="#require">Require</A> and
 <A HREF="mod_access.html">mod_access</A>.

 <P><HR>

 <H2><A NAME="scriptinterpretersource">ScriptInterpreterSource directive</A></H2>
 <!--%plaintext &lt;?INDEX {\tt ScriptInterpreterSource} directive&gt; -->
 <A
  HREF="directive-dict.html#Syntax"
  REL="Help"
 ><STRONG>Syntax:</STRONG></A> ScriptInterpreterSource registry|script<BR>
 <A
  HREF="directive-dict.html#Default"
  REL="Help"
 ><STRONG>Default:</STRONG></A> <CODE>ScriptInterpreterSource script</CODE>
 <BR>
 <A
  HREF="directive-dict.html#Context"
  REL="Help"
 ><STRONG>Context:</STRONG></A> directory, .htaccess<BR>
 <A
  HREF="directive-dict.html#Status"
  REL="Help"
 ><STRONG>Status:</STRONG></A> core (Windows only)<P>

 This directive is used to control how Apache 1.3.5 and later finds the interpreter
 used to run CGI scripts. The default technique is to use the interpreter pointed to by
 the #! line in the script.  Setting ScriptInterpreterSource registry will cause the
 Windows Registry to be searched using the script file extension (e.g., .pl) as a search key.
 <P><HR>

 <H2><A NAME="serveradmin">ServerAdmin directive</A></H2>
 <!--%plaintext &lt;?INDEX {\tt ServerAdmin} directive&gt; -->
 <A
  HREF="directive-dict.html#Syntax"
  REL="Help"
 ><STRONG>Syntax:</STRONG></A> ServerAdmin <EM>email-address</EM><BR>
 <A
  HREF="directive-dict.html#Context"
  REL="Help"
 ><STRONG>Context:</STRONG></A> server config, virtual host<BR>
 <A
  HREF="directive-dict.html#Status"
  REL="Help"
 ><STRONG>Status:</STRONG></A> core<P>

 The ServerAdmin sets the e-mail address that the server includes in any
 error messages it returns to the client.<P>

 It may be worth setting up a dedicated address for this, <EM>e.g.</EM>
 <BLOCKQUOTE><CODE>ServerAdmin www-admin@foo.bar.com</CODE></BLOCKQUOTE>
 as users do not always mention that they are talking about the server!<P><HR>

 <H2><A NAME="serveralias">ServerAlias directive</A></H2>

 <A
  HREF="directive-dict.html#Syntax"
  REL="Help"
 ><STRONG>Syntax:</STRONG></A> ServerAlias <EM>hostname</em> [<em>hostname</em>] ...<BR>
 <A
  HREF="directive-dict.html#Context"
  REL="Help"
 ><STRONG>Context:</STRONG></A> virtual host<BR>
 <A
  HREF="directive-dict.html#Status"
  REL="Help"
 ><STRONG>Status:</STRONG></A> core<BR>
 <A
  HREF="directive-dict.html#Compatibility"
  REL="Help"
 ><STRONG>Compatibility:</STRONG></A> ServerAlias is only available in Apache
 1.1 and later.<P>

 The ServerAlias directive sets the alternate names for a host, for use
 with
 <A HREF="../vhosts/name-based.html">name-based virtual hosts</A>.

 <P><STRONG>See also:</STRONG>
 <A HREF="../vhosts/">Apache Virtual Host documentation</A>

 <HR>

 <H2><A NAME="servername">ServerName directive</A></H2>
 <!--%plaintext &lt;?INDEX {\tt ServerName} directive&gt; -->
 <A
  HREF="directive-dict.html#Syntax"
  REL="Help"
 ><STRONG>Syntax:</STRONG></A> ServerName <EM>fully-qualified-domain-name</EM>
 <BR>
 <A
  HREF="directive-dict.html#Context"
  REL="Help"
 ><STRONG>Context:</STRONG></A> server config, virtual host<BR>
 <A
  HREF="directive-dict.html#Status"
  REL="Help"
 ><STRONG>Status:</STRONG></A> core<P>

 The ServerName directive sets the hostname of the server; this is
 used when creating redirection URLs. If it is not specified, then the
 server attempts to deduce it from its own IP address; however this may
 not work reliably, or may not return the preferred hostname. For example:
 <BLOCKQUOTE><CODE>ServerName www.example.com</CODE></BLOCKQUOTE>
 would be used if the canonical (main) name of the actual machine
 were <CODE>simple.example.com</CODE>.<P>

 If you are using <A HREF="../vhosts/name-based.html">name-based
 virtual hosts</A>, the <CODE>ServerName</CODE> inside a
 <A HREF="#virtualhost"><CODE>&lt;VirtualHost&gt;</CODE></A>
 section specifies what hostname must appear in the request's
 <CODE>Host:</CODE> header to match this virtual host.<P>

 <P><STRONG>See Also</STRONG>:<BR>
 <A HREF="../dns-caveats.html">DNS Issues</A><BR>
 <A HREF="../vhosts/">Apache virtual host documentation</A><BR>
 <A HREF="#usecanonicalname">UseCanonicalName</A><BR>
 <A HREF="#namevirtualhost">NameVirtualHost</A><BR>
 <A HREF="#serveralias">ServerAlias</A><BR>
 </P>
 <HR>

 <H2><A NAME="serverpath">ServerPath directive</A></H2>

 <A
  HREF="directive-dict.html#Syntax"
  REL="Help"
 ><STRONG>Syntax:</STRONG></A> ServerPath <EM>pathname</EM><BR>
 <A
  HREF="directive-dict.html#Context"
  REL="Help"
 ><STRONG>Context:</STRONG></A> virtual host<BR>
 <A
  HREF="directive-dict.html#Status"
  REL="Help"
 ><STRONG>Status:</STRONG></A> core<BR>
 <A
  HREF="directive-dict.html#Compatibility"
  REL="Help"
 ><STRONG>Compatibility:</STRONG></A> ServerPath is only available in Apache
 1.1 and later.<P>

 The ServerPath directive sets the legacy URL pathname for a host, for
 use with <A HREF="../vhosts/">name-based virtual hosts</A>.

 <P><STRONG>See also:</STRONG>
 <A HREF="../vhosts/">Apache Virtual Host documentation</A>

 <HR>

 <H2><A NAME="serverroot">ServerRoot directive</A></H2>
 <!--%plaintext &lt;?INDEX {\tt ServerRoot} directive&gt; -->
 <A
  HREF="directive-dict.html#Syntax"
  REL="Help"
 ><STRONG>Syntax:</STRONG></A> ServerRoot <EM>directory-filename</EM><BR>
 <A
  HREF="directive-dict.html#Default"
  REL="Help"
 ><STRONG>Default:</STRONG></A> <CODE>ServerRoot /usr/local/apache</CODE><BR>
 <A
  HREF="directive-dict.html#Context"
  REL="Help"
 ><STRONG>Context:</STRONG></A> server config<BR>
 <A
  HREF="directive-dict.html#Status"
  REL="Help"
 ><STRONG>Status:</STRONG></A> core<P>

 The ServerRoot directive sets the directory in which the server lives.
 Typically it will contain the subdirectories <CODE>conf/</CODE> and
 <CODE>logs/</CODE>. Relative paths for other configuration files are taken
 as relative to this directory.<P>

 See also <A HREF="../invoking.html">the <CODE>-d</CODE> option to httpd</A>.<P>
 See also <A HREF="../misc/security_tips.html#serverroot">the security tips</A>
 for information on how to properly set permissions on the ServerRoot.<P>

 <HR>

 <H2><A NAME="serversignature">ServerSignature directive</A></H2>
 <!--%plaintext &lt;?INDEX {\tt ServerSignature} directive&gt; -->
 <A
  HREF="directive-dict.html#Syntax"
  REL="Help"
 ><STRONG>Syntax:</STRONG></A> ServerSignature On|Off|EMail<BR>
 <A
  HREF="directive-dict.html#Default"
  REL="Help"
 ><STRONG>Default:</STRONG></A> <CODE>ServerSignature Off</CODE><BR>
 <A
  HREF="directive-dict.html#Context"
  REL="Help"
 ><STRONG>Context:</STRONG></A> server config, virtual host, directory,
 .htaccess<BR>
 <A
  HREF="directive-dict.html#Status"
  REL="Help"
 ><STRONG>Status:</STRONG></A> core<BR>
 <A
  HREF="directive-dict.html#Compatibility"
  REL="Help"
 ><STRONG>Compatibility:</STRONG></A> ServerSignature is only available in
 Apache
 1.3 and later.<P>

 The ServerSignature directive allows the configuration of a trailing
 footer line under server-generated documents (error messages,
 mod_proxy ftp directory listings, mod_info output, ...). The reason
 why you would want to enable such a footer line is that in a chain
 of proxies, the user often has no possibility to tell which of the
 chained servers actually produced a returned error message.<BR>
 The <SAMP>Off</SAMP> setting, which is the default, suppresses the
 error line (and is therefore compatible with the behavior of
 Apache-1.2 and below). The <SAMP>On</SAMP> setting simply adds a
 line with the server version number and <A
 HREF="#servername">ServerName</A> of the serving virtual host, and
 the <SAMP>EMail</SAMP> setting additionally creates a "mailto:"
 reference to the <A HREF="#serveradmin">ServerAdmin</A> of the
 referenced document.

 <HR>

 <H2><A NAME="servertokens">ServerTokens directive</A></H2>
 <!--%plaintext &lt;?INDEX {\tt ServerTokens} directive&gt; -->
 <A
  HREF="directive-dict.html#Syntax"
  REL="Help"
 ><STRONG>Syntax:</STRONG></A> ServerTokens Minimal|ProductOnly|OS|Full<BR>
 <A
  HREF="directive-dict.html#Default"
  REL="Help"
 ><STRONG>Default:</STRONG></A> <CODE>ServerTokens Full</CODE><BR>
 <A
  HREF="directive-dict.html#Context"
  REL="Help"
 ><STRONG>Context:</STRONG></A> server config <BR>
 <A
  HREF="directive-dict.html#Status"
  REL="Help"
 ><STRONG>Status:</STRONG></A> core<BR>
 <A
  HREF="directive-dict.html#Compatibility"
  REL="Help"
 ><STRONG>Compatibility:</STRONG></A> ServerTokens is only available
  in Apache 1.3 and later; the <code>ProductOnly</code> keyword is
  only available in versions later than 1.3.12

 <P>
 This directive controls whether <SAMP>Server</SAMP> response header
 field which is sent back to clients includes a description of the generic
 OS-type of the server as well as information about compiled-in modules.
 </P>
 <DL>
  <DT><CODE>ServerTokens Prod[uctOnly]</CODE>
  </DT>
  <DD>Server sends (<EM>e.g.</EM>): <SAMP>Server: Apache</SAMP>
  </DD>
  <DT><CODE>ServerTokens Min[imal]</CODE>
  </DT>
  <DD>Server sends (<EM>e.g.</EM>): <SAMP>Server: Apache/1.3.0</SAMP>
  </DD>
  <DT><CODE>ServerTokens OS</CODE>
  </DT>
  <DD>Server sends (<EM>e.g.</EM>): <SAMP>Server: Apache/1.3.0 (Unix)</SAMP>
  </DD>
  <DT><CODE>ServerTokens Full</CODE> (or not specified)
  </DT>
  <DD>Server sends (<EM>e.g.</EM>): <SAMP>Server: Apache/1.3.0 (Unix) PHP/3.0
   MyMod/1.2</SAMP>
  </DD>
 </DL>
 <P>
 This setting applies to the entire server, and cannot be enabled or
 disabled on a virtualhost-by-virtualhost basis.
 </P>

 <HR>

 <H2><A NAME="setinputfilter">SetInputFilter directive</A></H2>
 <P><A
  HREF="directive-dict.html#Syntax"
  REL="Help"
 ><STRONG>Syntax:</STRONG></A> SetInputFilter <EM>filter</EM>
 [<EM>filter</EM>] ...<BR>
 <A
  HREF="directive-dict.html#Default"
  REL="Help"
 ><STRONG>Default:</STRONG></A> none<BR>
 <A
  HREF="directive-dict.html#Context"
  REL="Help"
 ><STRONG>Context:</STRONG></A> directory<BR>
 <A
  HREF="directive-dict.html#Status"
  REL="Help"
 ><STRONG>Status:</STRONG></A> core</P>

 <p>The <code>SetInputFilter</code> directive sets the filters
 which will process client requests when they are received by the
 server.</p>

 <p>The order of the arguments determines the order in which the
 filters will process the content.</p>

 <p>See also the <a href="../filter.html">Filters</a> documentation.</p>


 <P><HR>
 <H2><A NAME="setoutputfilter">SetOutputFilter directive</A></H2>
 <P><A
  HREF="directive-dict.html#Syntax"
  REL="Help"
 ><STRONG>Syntax:</STRONG></A> SetOutputFilter <EM>filter</EM>
 [<EM>filter</EM>] ...<BR>
 <A
  HREF="directive-dict.html#Default"
  REL="Help"
 ><STRONG>Default:</STRONG></A> none<BR>
 <A
  HREF="directive-dict.html#Context"
  REL="Help"
 ><STRONG>Context:</STRONG></A> directory<BR>
 <A
  HREF="directive-dict.html#Status"
  REL="Help"
 ><STRONG>Status:</STRONG></A> core</P>

 <P>The <code>SetOutputFilter</code> directive sets the filters which
 will process responses from the server before they are sent to the
 client.  For example, the following configuration will process
 all files in the <code>/www/data/</code> directory for
 server-side includes.</P>

 <BLOCKQUOTE><CODE>
 &lt;Directory /www/data/&gt;<BR>
 &nbsp;&nbsp;SetOutputFilter INCLUDES<BR>
 &lt;/Directory&gt;
 </CODE></BLOCKQUOTE>

 <p>The order of the arguments determines the order in which the
 filters will process the content.</p>

 <p>See also the <a href="../filter.html">Filters</a> documentation.</p>

 <P><HR>
 <H2><A NAME="timeout">TimeOut directive</A></H2>
 <!--%plaintext &lt;?INDEX {\tt TimeOut} directive&gt; -->
 <A
  HREF="directive-dict.html#Syntax"
  REL="Help"
 ><STRONG>Syntax:</STRONG></A> TimeOut <EM>number</EM><BR>
 <A
  HREF="directive-dict.html#Default"
  REL="Help"
 ><STRONG>Default:</STRONG></A> <CODE>TimeOut 300</CODE><BR>
 <A
  HREF="directive-dict.html#Context"
  REL="Help"
 ><STRONG>Context:</STRONG></A> server config<BR>
 <A
  HREF="directive-dict.html#Status"
  REL="Help"
 ><STRONG>Status:</STRONG></A> core<P>

 The TimeOut directive currently defines the amount of time Apache will
 wait for three things:

 <OL>
   <LI>The total amount of time it takes to receive a GET request.
   <LI>The amount of time between receipt of TCP packets on a POST or
       PUT request.
   <LI>The amount of time between ACKs on transmissions of TCP packets
       in responses.
 </OL>

 We plan on making these separately configurable at some point down the
 road.  The timer used to default to 1200 before 1.2, but has been
 lowered to 300 which is still far more than necessary in most
 situations.  It is not set any lower by default because there may
 still be odd places in the code where the timer is not reset when
 a packet is sent.

 <P><HR>

 <H2><A NAME="usecanonicalname">UseCanonicalName directive</A></H2>
 <!--%plaintext &lt;?INDEX {\tt UseCanonicalName} directive&gt; -->
 <A HREF="directive-dict.html#Syntax" REL="Help">
 <STRONG>Syntax:</STRONG></A> UseCanonicalName on|off|dns<BR>
 <A HREF="directive-dict.html#Default" REL="Help">
 <STRONG>Default:</STRONG></A> <CODE>UseCanonicalName on</CODE><BR>
 <A HREF="directive-dict.html#Context" REL="Help">
 <STRONG>Context:</STRONG></A> server config, virtual host, directory<BR>
 <A HREF="directive-dict.html#Override" REL="Help">
 <STRONG>Override:</STRONG></A> Options<BR>
 <A HREF="directive-dict.html#Compatibility" REL="Help">
 <STRONG>Compatibility:</STRONG></A> UseCanonicalName is only available in
 Apache 1.3 and later<P>

 In many situations Apache has to construct a <EM>self-referential</EM>
 URL.  That is, a URL which refers back to the same server.
 With <CODE>UseCanonicalName on</CODE> (and in all versions prior to
 1.3) Apache will use the <A HREF="#servername">ServerName</A> and <A
 HREF="#port">Port</A> directives to construct a canonical name for the
 server.  This name is used in all self-referential URLs, and for the
 values of <CODE>SERVER_NAME</CODE> and <CODE>SERVER_PORT</CODE> in CGIs.

 <P>With <CODE>UseCanonicalName off</CODE> Apache will form
 self-referential URLs using the hostname and port supplied
 by the client if any are supplied (otherwise it will use the
 canonical name).  These values are the same that are used to
 implement <A HREF="../vhosts/name-based.html">name based virtual
 hosts</A>, and are available with the same clients.  The CGI variables
 <CODE>SERVER_NAME</CODE> and <CODE>SERVER_PORT</CODE> will be constructed
 from the client supplied values as well.

 <P>An example where this may be useful is on an intranet server where
 you have users connecting to the machine using short names such as
 <CODE>www</CODE>.  You'll notice that if the users type a shortname,
 and a URL which is a directory, such as <CODE>http://www/splat</CODE>,
 <EM>without the trailing slash</EM> then Apache will redirect them to
 <CODE>http://www.domain.com/splat/</CODE>.  If you have authentication
 enabled, this will cause the user to have to reauthenticate twice (once
 for <CODE>www</CODE> and once again for <CODE>www.domain.com</CODE>).
 But if <CODE>UseCanonicalName</CODE> is set off, then Apache will redirect
 to <CODE>http://www/splat/</CODE>.

 <P>There is a third option, <CODE>UseCanonicalName DNS</CODE>, which
 is intended for use with mass IP-based virtual hosting to support
 ancient clients that do not provide a <CODE>Host:</CODE> header. With
 this option Apache does a reverse DNS lookup on the server IP address
 that the client connected to in order to work out self-referential URLs.

 <P><STRONG>Warning:</STRONG> if CGIs make assumptions about the values of
 <CODE>SERVER_NAME</CODE> they may be broken by this option.  The client
 is essentially free to give whatever value they want as a hostname.
 But if the CGI is only using <CODE>SERVER_NAME</CODE> to construct
 self-referential URLs then it should be just fine.

 <P><STRONG>See also:</STRONG>
 <A HREF="#servername">ServerName</A>,
 <A HREF="#port">Port</A>

 <P><HR>

 <H2><A NAME="virtualhost">&lt;VirtualHost&gt; directive</A></H2>
 <!--%plaintext &lt;?INDEX {\tt VirtualHost} section directive&gt; -->
 <A
  HREF="directive-dict.html#Syntax"
  REL="Help"
 ><STRONG>Syntax:</STRONG></A> &lt;VirtualHost <EM>addr</EM>[:<EM>port</EM>]
 [<EM>addr</EM>[:<EM>port</EM>]] ...&gt; ...
 &lt;/VirtualHost&gt; <BR>
 <A
  HREF="directive-dict.html#Context"
  REL="Help"
 ><STRONG>Context:</STRONG></A> server config<BR>
 <A
  HREF="directive-dict.html#Status"
  REL="Help"
 ><STRONG>Status:</STRONG></A> Core.<BR>
 <A
  HREF="directive-dict.html#Compatibility"
  REL="Help"
 ><STRONG>Compatibility:</STRONG></A> Non-IP address-based Virtual Hosting only
 available in Apache 1.1 and later.<BR>
 <A
  HREF="directive-dict.html#Compatibility"
  REL="Help"
 ><STRONG>Compatibility:</STRONG></A> Multiple address support only available in
 Apache 1.2 and later.<P>

 &lt;VirtualHost&gt; and &lt;/VirtualHost&gt; are used to enclose a group of
 directives which will apply only to a particular virtual host.
 Any directive which is allowed in a virtual host context may be used.
 When the server receives a request for a document on a particular virtual
 host, it uses the configuration directives enclosed in the &lt;VirtualHost&gt;
 section. <EM>Addr</EM> can be
 <MENU>
 <LI>The IP address of the virtual host
 <LI>A fully qualified domain name for the IP address of the virtual host.
 </MENU> Example:
 <BLOCKQUOTE>
 <CODE>
 &lt;VirtualHost 10.1.2.3&gt; <BR>
 ServerAdmin webmaster@host.foo.com <BR>
 DocumentRoot /www/docs/host.foo.com <BR>
 ServerName host.foo.com <BR>
 ErrorLog logs/host.foo.com-error_log <BR>
 TransferLog logs/host.foo.com-access_log <BR>
 &lt;/VirtualHost&gt;
 </CODE></BLOCKQUOTE>

 Each VirtualHost must correspond to a different IP address, different port
 number or a
 different host name for the server, in the former case the server
 machine must be configured to accept IP packets for multiple
 addresses. (If the machine does not have multiple network interfaces,
 then this can be accomplished with the <CODE>ifconfig alias</CODE>
 command (if your OS supports it), or with kernel patches like <A
 HREF="../misc/vif-info.html">VIF</A> (for SunOS(TM) 4.1.x)).<P>

 The special name <CODE>_default_</CODE> can be specified in which case
 this virtual host will match any IP address that is not explicitly listed
 in another virtual host.  In the absence of any _default_ virtual host
 the "main" server config, consisting of all those definitions outside
 any VirtualHost section, is used when no match occurs.<P>

 You can specify a <CODE>:port</CODE> to change the port that is matched.
 If unspecified then it defaults to the same port as the most recent
 <CODE><A HREF="#port">Port</A></CODE> statement of the main server.  You
 may also specify <CODE>:*</CODE> to match all ports on that address.
 (This is recommended when used with <CODE>_default_</CODE>.)<P>

 <STRONG>SECURITY</STRONG>: See the
 <A HREF="../misc/security_tips.html">security tips</A>
 document for details on why your security could be compromised if
 the directory where logfiles are stored is writable by anyone other
 than the user that starts the server.

 <P><STRONG>NOTE</STRONG>: The use of &lt;VirtualHost&gt; does
 <STRONG>not</STRONG> affect what addresses Apache listens on. You may
 need to ensure that Apache is listening on the correct addresses using
 <A HREF="mpm_common.html#listen">Listen</A>.

 <P><STRONG>See also:</STRONG>
 <A HREF="../vhosts/">Apache Virtual Host documentation</A><BR>
 <STRONG>See also:</STRONG>
 <A HREF="../dns-caveats.html">Warnings about DNS and Apache</A><BR>
 <STRONG>See also:</STRONG>
 <A HREF="../bind.html">Setting which addresses and ports Apache uses</A><BR>
 <STRONG>See also</STRONG>: <A HREF="../sections.html">How Directory,
 Location and Files sections work</A> for an explanation of how these
 different sections are combined when a request is received
 </P>

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