#Network Time Servers (NTP)

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		<img src="ntp.png" class="img-thumbnail"/>
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			This page provides a quick guide to installing Network Time Protocol (NTP)
			on your Acme board for clock synchronization with an NTP server
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<br/>

[Network Time Protocol (NTP)](http://en.wikipedia.org/wiki/Network_Time_Protocol) 
is a networking protocol for clock 
synchronization between computer systems over packet-switched, 
variable-latency data networks. 

First, you'll need to install NTP from Debian repository using be this command:

<pre class="terminal">
apt-get update
apt-get install ntp
</pre>

<b>/etc/ntp.conf</b> contains the ntp configuration ad is already 
filled out for you.

An important part are the server lines. You can get a list of NTP server 
addresses at [www.pool.ntp.org](http://www.pool.ntp.org), find the 
preferred ones for your area, and then add them to the file. 

Then you'll need to restart or start the NTPD service:

<pre class="terminal">
/etc/init.d/ntp restart
</pre>

Now check the list of server used to syncronize your clock with this command:

<pre class="terminal">
<b>ntpq -c peers</b>
</pre>

<pre class="terminal">
     remote           refid      st t when poll reach   delay   offset  jitter
==============================================================================
+vodka.sublink.O 193.204.114.233  2 u    5  256   71   22.862   -3.480   1.927
-212.121.88.250  193.204.114.232  2 u  186  256  377   22.686   -7.755   2.703
+radha.parvati.i 193.204.114.233  2 u  176  256  177   20.278    2.958   2.015
 host22-187-177- .INIT.          16 u    - 1024    0    0.000    0.000   0.000
*golem.canonical 17.253.34.125    2 u    8  256  377   42.582   -3.391   1.657
</pre>

##Related links

* [Network Time Protocol](http://en.wikipedia.org/wiki/Network_Time_Protocol)
* [Package: ntp](https://packages.debian.org/wheezy/ntp)
* [Package: ntpdate](https://packages.debian.org/wheezy/ntpdate)