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[% page.title = 'How do I setup NTP to use the pool?' %]
<div class="block">
<h3><a name="use"></a>How do I use pool.ntp.org?</h3>
<p>
If you just want to synchronise your computers clock to the network, the
configuration file (for the ntpd program from the <a
href="http://www.ntp.org">ntp.org distribution</a>, on any supported operating
system - <b>Linux, *BSD, Windows and even some more exotic systems</b>) is
really simple:
</p>
<pre class="code">
driftfile /var/lib/ntp/ntp.drift
server 0.pool.ntp.org
server 1.pool.ntp.org
server 2.pool.ntp.org
server 3.pool.ntp.org</pre>
<p>
The 0, 1, 2 and 3.pool.ntp.org names point to a random set of servers that will
change every hour. Make sure your computer's clock is set to something
sensible (within a few minutes of the 'true' time) - you could use <tt>ntpdate
pool.ntp.org</tt>, or you could just use the <tt>date</tt> command and set it
to your wristwatch. Start ntpd, and after some time (this could take as long as
half an hour!), <tt>ntpq -pn</tt> should output something like:
</p>
<pre class="code ntpq">
avbidder:~$ ntpq -p
remote refid st t when poll reach delay offset jitter
==============================================================================
+81.6.42.224 193.5.216.14 2 u 68 1024 377 158.995 51.220 50.287
*217.162.232.173 130.149.17.8 2 u 191 1024 176 79.245 3.589 27.454
-129.132.57.95 131.188.3.222 3 u 766 1024 377 22.302 -2.928 0.508
</pre>
<p>
The IP addresses will be different, because you've been assigned random
timeservers. The essential thing is that one of the lines starts with an
asterisk (<tt>*</tt>), this means your computer gets the time from the internet
- you'll never have to worry about it again!
</p>
<p>
As <tt>pool.ntp.org</tt> will assign you timeservers from all over the
world, time quality will not be ideal. You get a bit better result if you use
the <a href="/zone/@">continental zones</a> (For example
<a href="/zone/europe">europe</a>,
<a href="/zone/north-america">north-america</a>,
<a href="/zone/oceania">oceania</a>
or <a href="/zone/asia">asia</a>.pool.ntp.org),
and even better time if you use the country zone (like
ch.pool.ntp.org in Switzerland) - for all these zones, you can again use the 0,
1 or 2 prefixes, like 0.ch.pool.ntp.org. Note, however, that the country zone
might not exist for your country, or might contain only one or two timeservers.
If you know timeservers that are really close to you (measured by network
distance, with <tt>traceroute</tt> or <tt>ping</tt>), time probably will be
even better.
</p>
<p>
If you're using <b>a recent Windows version</b>, you can use the ntp
client that is built into the system. As administrator enter</p>
<pre class="code">
w32tm /config /syncfromflags:manual /manualpeerlist:0.pool.ntp.org,1.pool.ntp.org,2.pool.ntp.org,3.pool.ntp.org
</pre>
<p>
at the command prompt. This will work on Windows 2003 and newer. If you use an
older version of windows you can try
<pre class="code">
net time /setsntp:"0.pool.ntp.org 1.pool.ntp.org 2.pool.ntp.org"
</pre>
The same
can be achieved by, as administrator, right-clicking the clock in the taskbar,
selecting 'Adjust Date/Time' and entering the server name in the 'Internet Time'
tab.
</p>
<p>
Meinberg made a port of the <a href="http://www.meinberg.de/english/sw/ntp.htm">ntp daemon for windows</a>.
</p>
<p>
If your Windows system is part of a domain, you might not be able to independently update your computer time.
For more information about setting the time on windows, see <a href="http://technet.microsoft.com/en-us/library/cc773013%28WS.10%29.aspx">How Windows Time Service Works</a>.
</p>
</div>
<div class="block">
<h3>Additional Notes</h3>
<p><span class="hook">If you have a static IP address and a reasonable Internet connection</span> (bandwidth
is not so important, but it should be stable and not too highly loaded), please
consider donating your server to the server pool. It doesn't cost you more than
a few hundred bytes per second traffic, but you help this project survive.
Please <a href="/join.html">read the joining page</a> for more information.
</p>
<p><span class="hook">If your Internet provider has a timeserver</span>, or if you know of a good timeserver
near you, you should use that and not this list - you'll probably get better
time and you'll use fewer network resources. If you know only one timeserver
near you, you can of course use that and two from pool.ntp.org or so.</p>
<p><span class="hook">It can rarely happen that you are assigned the same timeserver twice</span> -
just restarting the ntp server usually solves this problem. If you
use a country zone, please note that it may be because there is only
one server known in the project - better use a continental zone in
that case. You can <a href="/zone">browse the zones</a> to see how
many servers we have in each zone.</p>
<p><span class="hook">Be friendly</span>. Many servers are provided by volunteers, and almost all time
servers are really file or mail or webservers which just happen to also run ntp.
So don't use more than three time servers in your configuration, and don't play
dirty tricks with <tt>burst</tt> or <tt>minpoll</tt> - all you will gain is
that this project will be stopped sooner or later.</p>
<p><span class="hook">Make sure that the <i>time zone configuration</i> of your computer is correct</span>.
ntpd itself does not do anything about the time zones, it just uses UTC
internally.</p>
<p><span class="hook">If you are synchronising a network to pool.ntp.org</span>, please set up one of your
computers as a time server and synchronize the other computers to that one.
(you'll have some reading to do - it's not difficult though. And there's always
the <a href="news:comp.protocols.time.ntp"
>comp.protocols.time.ntp newsgroup</a>.)</p>
<p class="thanks">At this point, I'd like to thank those donating their time and timeservers to
this network.</p>
</div>
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