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<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Strict//EN"
    "http://www.w3.org/TR/xhtml1/DTD/xhtml1-strict.dtd">
<!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>Starting Apache</title>
  </head>
  <!-- Background white, links blue (unvisited), navy (visited), red (active) -->

  <body bgcolor="#FFFFFF" text="#000000" link="#0000FF"
  vlink="#000080" alink="#FF0000">
        <div align="CENTER">
      <img src="images/sub.gif" alt="[APACHE DOCUMENTATION]" /> 

      <h3>Apache HTTP Server</h3>
    </div>



    <h1 align="CENTER">Starting Apache</h1>

    <ul>
      <li>
        <a href="#unix">Starting Apache on Unix</a> 

        <ul>
          <li><a href="#errors">Errors During Start-up</a></li>

          <li><a href="#boot">Starting at Boot-Time</a></li>

          <li><a href="#info">Additional Information</a></li>
        </ul>
      </li>
    </ul>
    <hr />

    <h2><a id="unix" name="unix">Starting Apache on Unix</a></h2>

    <p>On Unix, the <a href="programs/httpd.html">httpd</a> program
    is run as a daemon which executes continuously in the
    background to handle requests. It is possible to have Apache
    invoked by the Internet daemon <code>inetd</code> each time a
    connection to the HTTP service is made using the <a
    href="mod/core.html#servertype">ServerType</a> directive, but
    this is not recommended.</p>

    <p>If the <a href="mod/core.html#port">Port</a> specified in
    the configuration file is the default of 80 (or any other port
    below 1024), then it is necessary to have root privileges in
    order to start Apache, so that it can bind to this privileged
    port. Once the server has started and completed a few
    preliminary activities such as opening its log files, it will
    launch several <em>child</em> processes which do the work of
    listening for and answering requests from clients. The main
    <code>httpd</code> process continues to run as the root user,
    but the child processes run as a less privileged user. This is
    controlled by Apache's <a
    href="server-wide.html#process">process creation
    directives</a>.</p>

    <p>The first thing that <code>httpd</code> does when it is
    invoked is to locate and read the <a
    href="configuring.html">configuration file</a>
    <code>httpd.conf</code>. The location of this file is set at
    compile-time, but it is possible to specify its location at run
    time using the <code>-f</code> command-line option as in</p>

    <blockquote>
      <code>/usr/local/apache/bin/httpd -f
      /usr/local/apache/conf/httpd.conf</code>
    </blockquote>

    <p>As an alternative to invoking the <code>httpd</code> binary
    directly, a shell script called <a
    href="programs/apachectl.html">apachectl</a> is provided which
    can be used to control the daemon process with simple commands
    such as <code>apachectl start</code> and <code>apachectl
    stop</code>.</p>

    <p>If all goes well during startup, the server will detach from
    the terminal and the command prompt will return almost
    immediately. This indicates that the server is up and running.
    You can then use your browser to connect to the server and view
    the test page in the <a
    href="mod/core.html#documentroot">DocumentRoot</a> directory
    and the local copy of the documentation linked from that
    page.</p>

    <h3><a id="errors" name="errors">Errors During
    Start-up</a></h3>

    <p>If Apache suffers a fatal problem during startup, it will
    write a message describing the problem either to the console or
    to the <a href="mod/core.html#errorlog">ErrorLog</a> before
    exiting. One of the most common error messages is "<code>Unable
    to bind to Port ...</code>". This message is usually caused by
    either:</p>

    <ul>
      <li>Trying to start the server on a privileged port when not
      logged in as the root user; or</li>

      <li>Trying to start the server when there is another instance
      of Apache or some other web server already bound to the same
      port.</li>
    </ul>

    <p>For further trouble-shooting instructions, consult the
    Apache <a href="misc/FAQ.html">FAQ</a>.</p>

    <h3><a id="boot" name="boot">Starting at Boot-Time</a></h3>

    <p>If you want your server to continue running after a system
    reboot, you should add a call to <code>httpd</code> or
    <code>apachectl</code> to your system startup files (typically
    <code>rc.local</code> or a file in an <code>rc.N</code>
    directory). This will start Apache as root. Before doing this
    ensure that your server is properly configured for security and
    access restrictions. The <code>apachectl</code> script is
    designed so that it can often be linked directly as an init
    script, but be sure to check the exact requirements of your
    system.</p>

    <h3><a id="info" name="info">Additional Information</a></h3>

    <p>Additional information about the command-line options of <a
    href="programs/httpd.html">httpd</a> and <a
    href="programs/apachectl.html">apachectl</a> as well as other
    support programs included with the server is available on the
    <a href="programs/">Server and Supporting Programs</a> page.
    There is also documentation on all the <a
    href="mod/">modules</a> included with the Apache distribution
    and the <a href="mod/directives.html">directives</a> that they
    provide.</p>
        <hr />

    <h3 align="CENTER">Apache HTTP Server</h3>
    <a href="./"><img src="images/index.gif" alt="Index" /></a>

  </body>
</html>