glfs/basicnet/netprogs/ntp/ntp-config.xml

<sect2>
<title>Configuring <application><acronym>NTP</acronym></application></title>

<sect3><title>Config files</title>
<para><filename>/etc/ntp.conf</filename></para>
</sect3>

<sect3><title>Configuration Information</title>

<para>The following configuration file defines various <acronym>NTP</acronym>
servers to use with the primary server designated with the prefer tag. It also
creates a drift file where <command>ntpd</command> stores the frequency
offset. Since the documentation included with the package is sparse,
visit the <acronym>NTP</acronym> website at
<ulink url="http://www.ntp.org/"/> for more information.</para>

<screen><userinput>server time-a.nist.gov prefer
server time-b.nist.gov
server tick.usno.navy.mil
driftfile /var/cache/ntp.drift</userinput></screen>
</sect3>

<sect3><title>Synchronizing the time</title>

<para>There are two options. Option one is to use run <command>ntpd</command>
continuously and allow it to synchronize the time in a gradual manner. The other
option is to run <command>ntpd</command> periodically (using cron)
and update the time each time <command>ntpd</command> is scheduled.</para>

<para>If you choose Option one, then create the bootscript
<filename>/etc/rc.d/init.d/ntp</filename> and put the start and
stop symlinks:</para>

<screen><userinput><command>cat &gt; /etc/rc.d/init.d/ntp &lt;&lt; "EOF"</command>
#!/bin/bash
# Begin $rc_base/init.d/ntp
source /etc/sysconfig/rc
source $rc_functions
case "$1" in
        start)
                echo "Starting ntpd..."
                loadproc ntpd
                ;;
        stop)
                echo "Stopping ntpd..."
                killproc ntpd
                ;;
        restart)
                $0 stop
                sleep 1
                $0 start
                ;;
        status)
                statusproc ntpd
                ;;
        *)
                echo "Usage: $0 {start|stop|restart|status}"
                exit 1
                ;;
esac
# End $rc_base/init.d/ntp
<command>EOF
chmod 755 /etc/rc.d/init.d/ntp
cd /etc/rc.d/init.d &amp;&amp;
ln -sf ../init.d/ntp ../rc0.d/K46ntp &amp;&amp;
ln -sf ../init.d/ntp ../rc1.d/K46ntp &amp;&amp;
ln -sf ../init.d/ntp ../rc2.d/K46ntp &amp;&amp;
ln -sf ../init.d/ntp ../rc3.d/S26ntp &amp;&amp;
ln -sf ../init.d/ntp ../rc4.d/S26ntp &amp;&amp;
ln -sf ../init.d/ntp ../rc5.d/S26ntp &amp;&amp;
ln -sf ../init.d/ntp ../rc6.d/K46ntp</command></userinput></screen>

<para>If you prefer to start ntpd periodically, add the following command to
the root's <filename>crontab</filename>:</para>
<screen><userinput>ntpd -q</userinput></screen>

</sect3>

</sect2>