<!DOCTYPE html PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN" 'http://www.w3.org/TR/html4/loose.dtd"'>
<html><head><meta http-equiv="Content-Type" content="text/html; charset=UTF-8"><title>Starting and Stopping an OpenACS instance.</title><link rel="stylesheet" type="text/css" href="openacs.css"><meta name="generator" content="DocBook XSL Stylesheets Vsnapshot"><link rel="home" href="index.html" title="OpenACS Core Documentation"><link rel="up" href="maintenance-web.html" title="Chapter 6. Production Environments"><link rel="previous" href="maintenance-web.html" title="Chapter 6. Production Environments"><link rel="next" href="install-openacs-inittab.html" title="AOLserver keepalive with inittab"></head><body bgcolor="white" text="black" link="#0000FF" vlink="#840084" alink="#0000FF"><div class="navheader"><a href="http://openacs.org"><img src="/doc/images/alex.jpg" style="border:0" alt="Alex logo"></a><table width="100%" summary="Navigation header" border="0"><tr><td width="20%" align="left"><a accesskey="p" href="maintenance-web.html">Prev</a> </td><th width="60%" align="center">Chapter 6. Production Environments</th><td width="20%" align="right"> <a accesskey="n" href="install-openacs-inittab.html">Next</a></td></tr></table><hr></div><div class="sect1"><div class="titlepage"><div><div><h2 class="title" style="clear: both"><a name="install-openacs-keepalive"></a>Starting and Stopping an OpenACS instance.</h2></div></div></div><p>The simplest way to start and stop and OpenACS site is to run the startup shell script provided, <code class="computeroutput">/var/lib/aolserver/<span class="replaceable"><span class="replaceable">$OPENACS_SERVICE_NAME</span></span>/etc/daemontools/run</code>. This runs as a regular task, and logs to the logfile. To stop the site, kill the script.</p><p>A more stable way to run OpenACS is with a "keepalive" mechanism of some sort, so that whenever the server halts or is stopped for a reset, it restarts automatically. This is recommended for development and production servers.</p><p>The Reference Platform uses Daemontools to control AOLserver. A simpler method, using <code class="computeroutput">init</code>, is <a class="link" href="install-openacs-inittab.html" title="AOLserver keepalive with inittab">here</a>.</p><div class="orderedlist"><ol class="orderedlist" type="1"><li class="listitem"><p>Daemontools must already be installed. If not, <a class="link" href="install-daemontools.html" title="Install Daemontools (OPTIONAL)">install it</a>.</p></li><li class="listitem"><p>Each service controlled by daemontools must have a
directory in <code class="computeroutput">/service</code>. That
directory must have a file called
<code class="computeroutput">run</code>. It works like this:</p><div class="itemizedlist"><ul class="itemizedlist" style="list-style-type: disc; "><li class="listitem"><p>The <code class="computeroutput">init</code> program starts every
time the computer is booted. </p></li><li class="listitem"><p>A line in <code class="computeroutput">init</code>'s configuration
file, <code class="computeroutput">/etc/inittab</code>, tells init to
run, and to restart if necessary,
<code class="computeroutput">svscanboot</code>.</p></li><li class="listitem"><p><code class="computeroutput">svscanboot</code> checks
the directory <code class="computeroutput">/service</code>
every few seconds.</p></li><li class="listitem"><p>If it sees a subdirectory there, it
looks for a file in the subdirectory called
<code class="computeroutput">run</code>. If it finds a run file, it creates a <code class="computeroutput">supervise</code> process</p></li><li class="listitem"><p><code class="computeroutput">supervise </code> executes the run script. Whenever the run script stops, <code class="computeroutput">supervise</code> executes it again. It also creates additional control files in the same directory. </p></li></ul></div><p>Hence, the AOLserver
instance for your development server is started by the file
<code class="computeroutput">/service/$OPENACS_SERVICE_NAME/run</code>.
But we use a symlink to make it easier to add and remove
stuff from the <code class="computeroutput">/service</code>, so
the actual location is
<code class="computeroutput">/var/lib/aolserver/<span class="replaceable"><span class="replaceable">$OPENACS_SERVICE_NAME</span></span>etc/daemontools/run</code>.</p><p>Daemontools creates additional files and directories to track status and
log. A daemontools directory is included in the OpenACS tarball at
<code class="computeroutput">/var/lib/aolserver/<span class="replaceable"><span class="replaceable">$OPENACS_SERVICE_NAME</span></span>/etc/daemontools</code>. To use it, first ill any existing AOLserver instances. As root, link the <code class="computeroutput">daemontools</code> directory into the <code class="computeroutput">/service</code> directory. Daemontools' <code class="computeroutput">svscan</code> process checks this directory every five seconds, and will quickly execute <code class="computeroutput">run</code>.</p><pre class="screen">[$OPENACS_SERVICE_NAME etc]$ <strong class="userinput"><code>killall nsd</code></strong>
nsd: no process killed
[$OPENACS_SERVICE_NAME etc]$ <strong class="userinput"><code>emacs /var/lib/aolserver/<span class="replaceable"><span class="replaceable">$OPENACS_SERVICE_NAME</span></span>/etc/daemontools/run</code></strong>
[$OPENACS_SERVICE_NAME etc]$ <strong class="userinput"><code>exit</code></strong>
[root root]# <strong class="userinput"><code>ln -s /var/lib/aolserver/<span class="replaceable"><span class="replaceable">$OPENACS_SERVICE_NAME</span></span>/etc/daemontools/ /service/<span class="replaceable"><span class="replaceable">$OPENACS_SERVICE_NAME</span></span></code></strong></pre><p>Verify that AOLserver is running.</p><pre class="screen">[root root]#<strong class="userinput"><code> ps -auxw | grep nsd</code></strong>
<span class="replaceable"><span class="replaceable">$OPENACS_SERVICE_NAME</span></span> 5562 14.4 6.2 22436 15952 ? S 11:55 0:04 /usr/local/aolserver/bin/nsd -it /var/lib/aolserver/<span class="replaceable"><span class="replaceable">$OPENACS_SERVICE_NAME</span></span>/etc/config.tcl -u serve
root 5582 0.0 0.2 3276 628 pts/0 S 11:55 0:00 grep nsd
[root root]#</pre></li><li class="listitem"><p>The user <span class="replaceable"><span class="replaceable">$OPENACS_SERVICE_NAME</span></span> can now control the service <span class="replaceable"><span class="replaceable">$OPENACS_SERVICE_NAME</span></span> with these commands:</p><div class="itemizedlist"><ul class="itemizedlist" style="list-style-type: disc; "><li class="listitem"><p>
<code class="computeroutput">svc -d /service/<span class="replaceable"><span class="replaceable">$OPENACS_SERVICE_NAME</span></span></code> -
Bring the server down
</p></li><li class="listitem"><p>
<code class="computeroutput">svc -u /service/<span class="replaceable"><span class="replaceable">$OPENACS_SERVICE_NAME</span></span></code> -
Start the server up and leave it in keepalive mode.
</p></li><li class="listitem"><p>
<code class="computeroutput">svc -o /service/<span class="replaceable"><span class="replaceable">$OPENACS_SERVICE_NAME</span></span></code> -
Start the server up once. Do not restart it if it stops.
</p></li><li class="listitem"><p>
<code class="computeroutput">svc -t /service/<span class="replaceable"><span class="replaceable">$OPENACS_SERVICE_NAME</span></span></code> -
Stop and immediately restart the server.
</p></li><li class="listitem"><p>
<code class="computeroutput">svc -k /service/<span class="replaceable"><span class="replaceable">$OPENACS_SERVICE_NAME</span></span></code> -
Sends the server a KILL signal. This is like KILL -9. AOLserver
exits immediately. If svc -t fails to fully kill AOLserver, use
this option. This does not take the server out of keepalive mode, so it should still bounce back up immediately.
</p></li></ul></div></li><li class="listitem"><p>Install a script to automate the stopping and starting
of AOLserver services via daemontools. You can then restart a service via <code class="computeroutput">restart-aolserver <span class="replaceable"><span class="replaceable">$OPENACS_SERVICE_NAME</span></span></code></p><pre class="screen">[root root]# <strong class="userinput"><code>cp /var/lib/aolserver/<span class="replaceable"><span class="replaceable">$OPENACS_SERVICE_NAME</span></span>/packages/acs-core-docs/www/files/restart-aolserver-daemontools.txt /usr/local/bin/restart-aolserver</code></strong>
[root root]# <strong class="userinput"><code>chmod 755 /usr/local/bin/restart-aolserver</code></strong>
[root root]#</pre></li><li class="listitem"><p>
At this point, these commands will work only for the
<code class="computeroutput">root</code> user. Grant permission for the <code class="computeroutput">web</code> group to use <code class="computeroutput">svc</code> commands on the <span class="emphasis"><em><span class="replaceable"><span class="replaceable">$OPENACS_SERVICE_NAME</span></span></em></span> server.</p><pre class="screen">[root root]# <strong class="userinput"><code>/usr/local/bin/svgroup web /service/<span class="replaceable"><span class="replaceable">$OPENACS_SERVICE_NAME</span></span></code></strong>
[root root]#</pre></li><li class="listitem"><p>Verify that the controls work. You may want to <code class="computeroutput">tail -f /var/lib/aolserver/<span class="replaceable"><span class="replaceable">$OPENACS_SERVICE_NAME</span></span>/log/<span class="replaceable"><span class="replaceable">$OPENACS_SERVICE_NAME</span></span>-error.log</code> in another window, so you can see what happens when you type these commands.
</p><p>
More information can be found on the <a class="ulink" href="http://panoptic.com/wiki/aolserver/How_to_start_stop_AOLserver_using_Daemontools" target="_top">AOLserver
Daemontools</a> page.
</p></li></ol></div><div class="table"><a name="id1417"></a><p class="title"><b>Table 6.1. How it Works</b></p><div class="table-contents"><table class="table" summary="How it Works" cellspacing="0" border="1"><colgroup><col><col><col><col><col><col></colgroup><thead><tr><th align="center">Program</th><th align="center">Invoked by this program ...</th><th align="center">... using this file</th><th align="center">Where to find errors</th><th align="center">Log goes to</th><th align="center">Use these commands to control it</th></tr></thead><tbody><tr><td align="center">svscanboot
</td><td align="center">init</td><td align="center">/etc/inittab</td><td align="center">ps -auxw | grep readproctitle</td><td align="center">n/a</td><td align="center"> </td></tr><tr><td align="center">aolserver</td><td align="center"><code class="computeroutput"></code>supervise
(a child of svscanboot)</td><td align="center">/service/<span class="replaceable"><span class="replaceable">$OPENACS_SERVICE_NAME</span></span>/run</td><td align="center">/var/lib/aolserver/<span class="replaceable"><span class="replaceable">$OPENACS_SERVICE_NAME</span></span>/log/error.log</td><td align="center">/var/lib/aolserver/<span class="replaceable"><span class="replaceable">$OPENACS_SERVICE_NAME</span></span>/log/$OPENACS_SERVICE_NAME.log</td><td align="center">svc -k /service/<span class="replaceable"><span class="replaceable">$OPENACS_SERVICE_NAME</span></span></td></tr><tr><td align="center">postgresql</td><td align="center">Redhat init scripts during boot</td><td align="center">/etc/init.d/postgresql</td><td align="center">/usr/local/pgsql/data/server.log</td><td align="center"> </td><td align="center">service postgresql start (Red Hat), /etc/init.d/postgresql start (Debian)</td></tr></tbody></table></div></div><br class="table-break"></div><div class="navfooter"><hr><table width="100%" summary="Navigation footer"><tr><td width="40%" align="left"><a accesskey="p" href="maintenance-web.html">Prev</a> </td><td width="20%" align="center"><a accesskey="h" href="index.html">Home</a></td><td width="40%" align="right"> <a accesskey="n" href="install-openacs-inittab.html">Next</a></td></tr><tr><td width="40%" align="left">Chapter 6. Production Environments </td><td width="20%" align="center"><a accesskey="u" href="maintenance-web.html">Up</a></td><td width="40%" align="right"> AOLserver keepalive with inittab</td></tr></table><hr><address><a href="mailto:docs@openacs.org">docs@openacs.org</a></address></div><a name="comments"></a></body></html>