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<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN"
    "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">

<html xmlns="http://www.w3.org/1999/xhtml">
  <head>
    <meta name="generator" content="HTML Tidy, see www.w3.org" />

    <title>Apache MPM Common Directives</title>
  </head>
  <!-- Background white, links blue (unvisited), navy (visited), red (active) -->

  <body bgcolor="#FFFFFF" text="#000000" link="#0000FF"
  vlink="#000080" alink="#FF0000">
    <!--#include virtual="header.html" -->

    <h1 align="CENTER">Multi-Processing Module Common
    Directives</h1>

    <p>This file documents directives that are implemented by more
    than one multi-processing module (MPM).</p>

    <h2>Directives</h2>

    <ul>
      <li><a href="#connectionstatus">ConnectionStatus</a></li>

      <li><a href="#coredumpdirectory">CoreDumpDirectory</a></li>

      <li><a href="#group">Group</a></li>

      <li><a href="#pidfile">PidFile</a></li>

      <li><a href="#listen">Listen</a></li>

      <li><a href="#listenbacklog">ListenBacklog</a></li>

      <li><a href="#lockfile">LockFile</a></li>

      <li><a href="#maxclients">MaxClients</a></li>

      <li><a
      href="#maxrequestsperchild">MaxRequestsPerChild</a></li>

      <li><a href="#maxsparethreads">MaxSpareThreads</a></li>

      <li><a href="#maxthreadsperchild">MaxThreadsPerChild</a></li>

      <li><a href="#minsparethreads">MinSpareThreads</a></li>

      <li><a href="#numservers">NumServers</a></li>

      <li><a href="#scoreboardfile">ScoreBoardFile</a></li>

      <li><a href="#sendbuffersize">SendBufferSize</a></li>

      <li><a href="#startservers">StartServers</a></li>

      <li><a href="#startthreads">StartThreads</a></li>

      <li><a href="#threadsperchild">ThreadsPerChild</a></li>

      <li><a href="#user">User</a></li>
    </ul>
    <hr />

    <h2><a id="connectionstatus"
    name="connectionstatus">ConnectionStatus directive</a></h2>

    <p><a href="directive-dict.html#Syntax"
    rel="Help"><strong>Syntax:</strong></a> ConnectionStatus
    on|off<br />
     <a href="directive-dict.html#Default"
    rel="Help"><strong>Default:</strong></a> <code>ConnectionStatus
    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> MPM<br />
     <a href="directive-dict.html#Module"
    rel="Help"><strong>Module:</strong></a> perchild</p>

    <p>Whether or not to maintain status information on current
    connections. If this is off then mod_status will not work
    properly.</p>
    <hr />

    <h2><a id="coredumpdirectory"
    name="coredumpdirectory">CoreDumpDirectory directive</a></h2>
    <!--%plaintext &lt;?INDEX {\tt CoreDumpDirectory} directive&gt; -->

    <p><a href="directive-dict.html#Syntax"
    rel="Help"><strong>Syntax:</strong></a> CoreDumpDirectory
    <em>directory</em><br />
     <a href="directive-dict.html#Default"
    rel="Help"><strong>Default:</strong></a> the same location as
    ServerRoot<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> MPM<br />
     <a href="directive-dict.html#Module"
    rel="Help"><strong>Module:</strong></a> threaded, perchild,
    prefork, mpm_winnt</p>

    <p>This controls the directory to which Apache attempts to
    switch before dumping core. The default is in the <a
    href="core.html#serverroot">ServerRoot</a> directory, however
    since this should not be writable by the user the server runs
    as, core dumps won't normally get written. If you want a core
    dump for debugging, you can use this directive to place it in a
    different location.</p>
    <hr />

    <h2><a id="group" name="group">Group directive</a></h2>
    <!--%plaintext &lt;?INDEX {\tt Group} directive&gt; -->

    <p><a href="directive-dict.html#Syntax"
    rel="Help"><strong>Syntax:</strong></a> Group
    <em>unix-group</em><br />
     <a href="directive-dict.html#Default"
    rel="Help"><strong>Default:</strong></a> <code>Group
    #-1</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> MPM<br />
     <a href="directive-dict.html#Module"
    rel="Help"><strong>Module:</strong></a> threaded, perchild,
    prefork</p>
    The Group directive sets the group under which the server will
    answer requests. In order to use this directive, the
    stand-alone server must be run initially as root.
    <em>Unix-group</em> is one of: 

    <dl>
      <dt>A group name</dt>

      <dd>Refers to the given group by name.</dd>

      <dt># followed by a group number.</dt>

      <dd>Refers to a group by its number.</dd>
    </dl>
    It is recommended that you set up a new group specifically for
    running the server. Some admins use user <code>nobody</code>,
    but this is not always possible or desirable. 

    <p>Note: if you start the server as a non-root user, it will
    fail to change to the specified group, and will instead
    continue to run as the group of the original user.</p>

    <p>Special note: Use of this directive in &lt;VirtualHost&lt;
    is no longer supported. To implement the <a
    href="../suexec.html">suEXEC wrapper</a> with Apache 2.0, use
    the <a
    href="mod_suexec.html#suexecusergroup">SuexecUserGroup</a>
    directive. SECURITY: See <a href="#user">User</a> for a
    discussion of the security considerations.</p>
    <hr />

    <h2><a id="pidfile" name="pidfile">PidFile directive</a></h2>
    <!--%plaintext &lt;?INDEX {\tt PidFile} directive&gt; -->

    <p><a href="directive-dict.html#Syntax"
    rel="Help"><strong>Syntax:</strong></a> PidFile
    <em>filename</em><br />
     <a href="directive-dict.html#Default"
    rel="Help"><strong>Default:</strong></a> <code>PidFile
    logs/httpd.pid</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> MPM<br />
     <a href="directive-dict.html#Module"
    rel="Help"><strong>Module:</strong></a> threaded, perchild,
    prefork, mpm_winnt</p>

    <p>The PidFile directive sets the file to which the server
    records the process id of the daemon. If the filename does not
    begin with a slash (/) then it is assumed to be relative to the
    <a href="core.html#serverroot">ServerRoot</a>.</p>

    <p>It is often useful to be able to send the server a signal,
    so that it closes and then reopens its <a
    href="core.html#errorlog">ErrorLog</a> and TransferLog, and
    re-reads its configuration files. This is done by sending a
    SIGHUP (kill -1) signal to the process id listed in the
    PidFile.</p>

    <p>The PidFile is subject to the same warnings about log file
    placement and <a
    href="../misc/security_tips.html#serverroot">security</a>.</p>
    <hr />

    <h2><a id="listen" name="listen">Listen directive</a></h2>

    <p><a href="directive-dict.html#Syntax"
    rel="Help"><strong>Syntax:</strong></a> Listen
    [<em>IP-address</em>:]<em>port number</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> MPM<br />
     <a href="directive-dict.html#Module"
    rel="Help"><strong>Module:</strong></a> threaded, perchild,
    prefork, mpm_winnt</p>

    <p>The Listen directive instructs Apache to listen to only
    specific IP addresses or ports; by default it responds to
    requests on all IP interfaces. The Listen directive is now
    a required directive. If it is not in the config file, the
    server will fail to start. This is a change from previous
    versions of Apache.

    <p>The Listen directive tells the server to accept incoming
    requests on the specified port or address-and-port combination.
    If only a port number is specified, the server listens to the
    given port on all interfaces. If an IP address is given as well 
    as a port, the server will listen on the given port and
    interface.</p>

    <p>Multiple Listen directives may be used to specify a number
    of addresses and ports to listen to. The server will respond to
    requests from any of the listed addresses and ports.</p>

    <p>For example, to make the server accept connections on both
    port 80 and port 8000, use:</p>
<pre>
   Listen 80
   Listen 8000
</pre>
    To make the server accept connections on two specified
    interfaces and port numbers, use 
<pre>
   Listen 192.170.2.1:80
   Listen 192.170.2.5:8000
</pre>

    <p><strong>See Also:</strong> <a href="../dns-caveats.html">DNS
    Issues</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="http://www.apache.org/info/known_bugs.html#listenbug">Known
    Bugs</a></p>
    <hr />

    <h2><a id="listenbacklog" name="listenbacklog">ListenBacklog
    directive</a></h2>

    <p><a href="directive-dict.html#Syntax"
    rel="Help"><strong>Syntax:</strong></a> ListenBacklog
    <em>backlog</em><br />
     <a href="directive-dict.html#Default"
    rel="Help"><strong>Default:</strong></a> <code>ListenBacklog
    511</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> MPM<br />
     <a href="directive-dict.html#Module"
    rel="Help"><strong>Module:</strong></a> threaded, perchild,
    prefork, mpm_winnt</p>

    <p>The maximum length of the queue of pending connections.
    Generally no tuning is needed or desired, however on some
    systems it is desirable to increase this when under a TCP SYN
    flood attack. See the backlog parameter to the
    <code>listen(2)</code> system call.</p>

    <p>This will often be limited to a smaller number by the
    operating system. This varies from OS to OS. Also note that
    many OSes do not use exactly what is specified as the backlog,
    but use a number based on (but normally larger than) what is
    set.</p>
    <hr />

    <h2><a id="lockfile" name="lockfile">LockFile
    directive</a></h2>

    <p><a href="directive-dict.html#Syntax"
    rel="Help"><strong>Syntax:</strong></a> LockFile
    <em>filename</em><br />
     <a href="directive-dict.html#Default"
    rel="Help"><strong>Default:</strong></a> <code>LockFile
    logs/accept.lock</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> MPM<br />
     <a href="directive-dict.html#Module"
    rel="Help"><strong>Module:</strong></a> threaded, perchild,
    prefork</p>

    <p>The LockFile directive sets the path to the lockfile used
    when Apache is compiled with either USE_FCNTL_SERIALIZED_ACCEPT
    or USE_FLOCK_SERIALIZED_ACCEPT. This directive should normally
    be left at its default value. The main reason for changing it
    is if the <code>logs</code> directory is NFS mounted, since
    <strong>the lockfile must be stored on a local disk</strong>.
    The PID of the main server process is automatically appended to
    the filename.</p>

    <p><strong>SECURITY:</strong> It is best to avoid putting this
    file in a world writable directory such as
    <code>/var/tmp</code> because someone could create a denial of
    service attack and prevent the server from starting by creating
    a lockfile with the same name as the one the server will try to
    create.</p>
    <hr />

    <h2><a id="maxclients" name="maxclients">MaxClients
    directive</a></h2>
    <!--%plaintext &lt;?INDEX {\tt MaxClients} directive&gt; -->

    <p><a href="directive-dict.html#Syntax"
    rel="Help"><strong>Syntax:</strong></a> MaxClients
    <em>number</em><br />
     <a href="directive-dict.html#Default"
    rel="Help"><strong>Default:</strong></a> <code>MaxClients
    8</code> (with threads) <code>MaxClients 256</code> (no
    threads)<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> MPM<br />
     <a href="directive-dict.html#Module"
    rel="Help"><strong>Module:</strong></a> threaded, prefork</p>

    <p>The MaxClients directive sets the limit on the number of
    child processes that will be created to serve requests. When
    the server is built without threading, no more than this number
    of clients can be served simultaneously. To configure more than
    256 clients, you must edit the <code>HARD_SERVER_LIMIT</code>
    entry in <code>mpm_default.h</code> and recompile.</p>

    <p>Any connection attempts over the MaxClients limit will
    normally be queued, up to a number based on the <a
    href="#listenbacklog">ListenBacklog</a> directive. Once a child
    process is freed at the end of a different request, the
    connection will then be serviced.</p>

    <p>When the server is compiled with threading, then the maximum
    number of simultaneous requests that can be served is obtained
    from the value of this directive multiplied by <a
    href="#threadsperchild">ThreadsPerChild</a>.</p>
    <hr />

    <h2><a id="maxrequestsperchild"
    name="maxrequestsperchild">MaxRequestsPerChild
    directive</a></h2>
    <!--%plaintext &lt;?INDEX {\tt MaxRequestsPerChild} directive&gt; -->

    <p><a href="directive-dict.html#Syntax"
    rel="Help"><strong>Syntax:</strong></a> MaxRequestsPerChild
    <em>number</em><br />
     <a href="directive-dict.html#Default"
    rel="Help"><strong>Default:</strong></a>
    <code>MaxRequestsPerChild 10000</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> MPM<br />
     <a href="directive-dict.html#Module"
    rel="Help"><strong>Module:</strong></a> threaded, prefork,
    perchild, mpm_winnt</p>

    <p>The MaxRequestsPerChild directive sets the limit on the
    number of requests that an individual child server process will
    handle. After MaxRequestsPerChild requests, the child process
    will die. If MaxRequestsPerChild is 0, then the process will
    never expire.</p>

    <p>Setting MaxRequestsPerChild to a non-zero limit has two
    beneficial effects:</p>

    <ul>
      <li>it limits the amount of memory that process can consume
      by (accidental) memory leakage;</li>

      <li>by giving processes a finite lifetime, it helps reduce
      the number of processes when the server load reduces.</li>
    </ul>

    <p><strong>NOTE:</strong> For <em>KeepAlive</em> requests, only
    the first request is counted towards this limit. In effect, it
    changes the behavior to limit the number of
    <em>connections</em> per child.</p>
    <hr />

    <h2><a id="maxsparethreads"
    name="maxsparethreads">MaxSpareThreads directive</a></h2>

    <p><a href="directive-dict.html#Syntax"
    rel="Help"><strong>Syntax:</strong></a> MaxSpareThreads
    <em>number</em><br />
     <a href="directive-dict.html#Default"
    rel="Help"><strong>Default:</strong></a> <code>MaxSpareThreads
    10 (Perchild) or 500 (threaded)</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#Module"
    rel="Help"><strong>Module:</strong></a> threaded, perchild</p>

    <p>Maximum number of idle threads. Different MPMs deal with
    this directive differently. Perchild monitor the number of idle
    threads on a per-child basis. If there are too many idle
    threads in that child, the server will begin to kill threads
    within that child.</p>

    <p>threaded deals with idle threads on a server-wide basis. If
    there are too many idle threads in the server then child
    processes are killed until the number of idle threads is less
    than this number.</p>

    <p>See also <a href="#minsparethreads">MinSpareThreads</a> and
    <a href="#startservers">StartServers</a>.</p>
    <hr />

    <h2><a id="maxthreadsperchild"
    name="maxthreadsperchild">MaxThreadsPerChild directive</a></h2>

    <p><a href="directive-dict.html#Syntax"
    rel="Help"><strong>Syntax:</strong></a> MaxThreadsPerChild
    <em>number</em><br />
     <a href="directive-dict.html#Default"
    rel="Help"><strong>Default:</strong></a>
    <code>MaxThreadsPerChild 64</code> <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#Module"
    rel="Help"><strong>Module:</strong></a> threaded, perchild</p>

    <p>Maximum number of threads per child. For MPMs with a
    variable number of threads per child, this directive sets the
    maximum number of threads that will be created in each child
    process. To increase this value beyond its default, it is
    necessary to change the value of the compile-time define
    <code>HARD_THREAD_LIMIT</code> and recompile the server.</p>
    <hr />

    <h2><a id="minsparethreads"
    name="minsparethreads">MinSpareThreads directive</a></h2>
    <!--%plaintext &lt;?INDEX {\tt MinSpareServers} directive&gt; -->

    <p><a href="directive-dict.html#Syntax"
    rel="Help"><strong>Syntax:</strong></a> MinSpareServers
    <em>number</em><br />
     <a href="directive-dict.html#Default"
    rel="Help"><strong>Default:</strong></a> <code>MaxSpareThreads
    5 (Perchild) or 250 (threaded)</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#Module"
    rel="Help"><strong>Module:</strong></a> threaded, perchild</p>

    <p>Minimum number of idle threads to handle request spikes.
    Different MPMs deal with this directive differently. Perchild
    monitor the number of idle threads on a per-child basis. If
    there aren't enough idle threads in that child, the server will
    begin to create new threads within that child.</p>

    <p>threaded deals with idle threads on a server-wide basis. If
    there aren't enough idle threads in the server then child
    processes are created until the number of idle threads is
    greater than number.</p>
    See also <a href="#maxsparethreads">MaxSpareThreads</a> and <a
    href="#startservers">StartServers</a>. 
    <hr />

    <h2><a id="numservers" name="numservers">NumServers
    directive</a></h2>

    <p><a href="directive-dict.html#Syntax"
    rel="Help"><strong>Syntax:</strong></a> NumServers
    <em>number</em><br />
     <a href="directive-dict.html#Default"
    rel="Help"><strong>Default:</strong></a> <code>NumServers
    2</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> MPM<br />
     <a href="directive-dict.html#Module"
    rel="Help"><strong>Module:</strong></a> perchild</p>

    <p>Number of children alive at the same time. MPMs that use
    this directive do not dynamically create new child processes so
    this number should be large enough to handle the requests for
    the entire site.</p>
    <hr />

    <h2><a id="scoreboardfile" name="scoreboardfile">ScoreBoardFile
    directive</a></h2>
    <!--%plaintext &lt;?INDEX {\tt ScoreBoardFile} directive&gt; -->

    <p><a href="directive-dict.html#Syntax"
    rel="Help"><strong>Syntax:</strong></a> ScoreBoardFile
    <em>filename</em><br />
     <a href="directive-dict.html#Default"
    rel="Help"><strong>Default:</strong></a> <code>ScoreBoardFile
    logs/apache_status</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> MPM<br />
     <a href="directive-dict.html#Compatibility" rel="Help"></a> <a
    href="directive-dict.html#Module"
    rel="Help"><strong>Module:</strong></a> threaded, perchild,
    prefork</p>

    <p>The ScoreBoardFile directive is required on some
    architectures to place a file that the server will use to
    communicate between its children and the parent. The easiest
    way to find out if your architecture requires a scoreboard file
    is to run Apache and see if it creates the file named by the
    directive. If your architecture requires it then you must
    ensure that this file is not used at the same time by more than
    one invocation of Apache.</p>

    <p>If you have to use a ScoreBoardFile then you may see
    improved speed by placing it on a RAM disk. But be careful that
    you heed the same warnings about log file placement and <a
    href="../misc/security_tips.html">security</a>.</p>

    <p><strong>See Also</strong>: <a
    href="../stopping.html">Stopping and Restarting Apache</a></p>
    <hr />

    <h2><a id="sendbuffersize" name="sendbuffersize">SendBufferSize
    directive</a></h2>
    <!--%plaintext &lt;?INDEX {\tt SendBufferSize} directive&gt; -->

    <p><a href="directive-dict.html#Syntax"
    rel="Help"><strong>Syntax:</strong></a> SendBufferSize
    <em>bytes</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> MPM<br />
     <a href="directive-dict.html#Module"
    rel="Help"><strong>Module:</strong></a> threaded, perchild,
    prefork, mpm_winnt</p>
    The server will set the TCP buffer size to the number of bytes
    specified. Very useful to increase past standard OS defaults on
    high speed high latency (<em>i.e.</em>, 100ms or so, such as
    transcontinental fast pipes) 
    <hr />

    <h2><a id="startservers" name="startservers">StartServers
    directive</a></h2>
    <!--%plaintext &lt;?INDEX {\tt StartServers} directive&gt; -->

    <p><a href="directive-dict.html#Syntax"
    rel="Help"><strong>Syntax:</strong></a> StartServers
    <em>number</em><br />
     <a href="directive-dict.html#Default"
    rel="Help"><strong>Default:</strong></a> <code>StartServers
    5</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> MPM<br />
     <a href="directive-dict.html#Module"
    rel="Help"><strong>Module:</strong></a> threaded, prefork</p>

    <p>The StartServers directive sets the number of child server
    processes created on startup. As the number of processes is
    dynamically controlled depending on the load, there is usually
    little reason to adjust this parameter.</p>

    <p>See also <a href="#minsparethreads">MinSpareThreads</a> and
    <a href="#maxsparethreads">MaxSpareThreads</a>.</p>
    <hr />

    <h2><a id="startthreads" name="startthreads">StartThreads
    directive</a></h2>

    <p><a href="directive-dict.html#Syntax"
    rel="Help"><strong>Syntax:</strong></a> StartThreads
    <em>number</em><br />
     <a href="directive-dict.html#Default"
    rel="Help"><strong>Default:</strong></a> <code>StartThreads
    5</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> MPM<br />
     <a href="directive-dict.html#Module"
    rel="Help"><strong>Module:</strong></a> perchild</p>

    <p>Number of threads each child creates on startup. As the
    number of threads is dynamically controlled depending on the
    load, there is usually little reason to adjust this
    parameter.</p>
    <hr />

    <h2><a id="threadsperchild"
    name="threadsperchild">ThreadsPerChild</a></h2>

    <p><a href="directive-dict.html#Syntax"
    rel="Help"><strong>Syntax:</strong></a> ThreadsPerChild
    <em>number</em><br />
     <a href="directive-dict.html#Default"
    rel="Help"><strong>Default:</strong></a> <code>ThreadsPerChild
    50</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> MPM<br />
     <a href="directive-dict.html#Module"
    rel="Help"><strong>Module:</strong></a> threaded, mpm_winnt</p>

    <p>This directive sets the number of threads created by each
    child process. The child creates these threads at startup and
    never creates more. if using an MPM like mpmt_winnt, where
    there is only one child process, this number should be high
    enough to handle the entire load of the server. If using an MPM
    like threaded, where there are multiple child processes, the
    total number of threads should be high enough to handle the
    common load on the server.</p>
    <hr />

    <h2><a id="user" name="user">User directive</a></h2>
    <!--%plaintext &lt;?INDEX {\tt User} directive&gt; -->

    <p><a href="directive-dict.html#Syntax"
    rel="Help"><strong>Syntax:</strong></a> User
    <em>unix-userid</em><br />
     <a href="directive-dict.html#Default"
    rel="Help"><strong>Default:</strong></a> <code>User
    #-1</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#Module"
    rel="Help"><strong>Module:</strong></a> threaded, perchild,
    prefork</p>
    The User directive sets the userid as which the server will
    answer requests. In order to use this directive, the standalone
    server must be run initially as root. <em>Unix-userid</em> is
    one of: 

    <dl>
      <dt>A username</dt>

      <dd>Refers to the given user by name.</dd>

      <dt># followed by a user number.</dt>

      <dd>Refers to a user by their number.</dd>
    </dl>
    The user should have no privileges which result in it being
    able to access files which are not intended to be visible to
    the outside world, and similarly, the user should not be able
    to execute code which is not meant for httpd requests. It is
    recommended that you set up a new user and group specifically
    for running the server. Some admins use user
    <code>nobody</code>, but this is not always possible or
    desirable. For example mod_proxy's cache, when enabled, must be
    accessible to this user (see <a
    href="mod_proxy.html">mod_proxy's</a> <code>CacheRoot</code>
    directive). 

    <p>Notes: If you start the server as a non-root user, it will
    fail to change to the lesser privileged user, and will instead
    continue to run as that original user. If you do start the
    server as root, then it is normal for the parent process to
    remain running as root.</p>

    <p>Special note: Use of this directive in &lt;VirtualHost&gt;
    is no longer supported. To configure your server for <a
    href="mod_suexec.html">suexec</a> use <a
    href="mod_suexec.html#suexecusergroup">SuexecUserGroup</a>.
    SECURITY: Don't set User (or <a href="#group">Group</a>) to
    <code>root</code> unless you know exactly what you are doing,
    and what the dangers are.</p>

    <p><!--#include virtual="footer.html" -->
    </p>
  </body>
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