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Clock Drift and NTP

July 15, 2011 • Customer Services       

Synopsis

Article

Clock drift can be a major problem with many onboard clocks. In order to keep your clock correct you can make use of the Network Time Protocol (NTP).

Before you start, you should ascertain the name or IP address of a time server that is topologically close to you. This is often one run by your ISP or other network provider.

Armed with that information, log into your CNv4 and type :-

apt-get update

apt-get install ntp

The package is installed. Now you need to edit the file called /etc/ntp.conf. Perform the following commands :-

cd /etc

nano ntp.conf

You will note the following two lines in the file

# You do need to talk to an NTP server or two (or three).
#server ntp.your-provider.example

Simply add one (or more) server lines to the file.

Press ctrl-o followed by return to save the file. Press ctrl-x to return to the command line.

Finally, restart your ntp service by typing the following command :-

/etc/init.d/ntp restart

After this, your system will keep near perfect time.

Note: If your clock is currently wildly out you may need to use the date command to set the time approximately correctly. NTP will then get your clock properly synchronised.

Note: If you are running in a virtual environment there are alternate methods to keep your clock in sync.

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