Ubuntu NTPd Time Server

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Ubuntu time/date with NTP daemon

ntpdate runs on system boot and (theoretically) sets the clock, but if your are using a server / leave your pc on a long time / network isnt up when it tries, then time drifts. Either set a cron job to run it constantly or use ntp daemon to keep it constantly tweaked.

Install

Check what/if anything currently running

ps aux | grep -i ntp
#or
sudo service ntp status

If nothing is running install ntp

sudo apt-get install ntp

This should immediately sync and just work. The default time servers (e.g. server 1.ubuntu.pool.ntp.org) etc. are in /etc/ntp.conf


ntp.conf

Can add working servers to /etc/ntp.conf. Add a line in the config file like this.

#Use Ubuntu's ntp server as a fallback.
server ntp.ubuntu.com
#My own fallback server
server ntp3a.le.ac.uk

Fix

Sometimes it doesn't sync (possibly if its miles out?) automatically, to manually force a resync you must stop ntp service, manually run ntpdate (wont work with service still running) , then restart ntp service.

$ sudo service ntp stop
#enter a working NTP server e.g. time.windows.com or ntp3a.le.ac.uk
$ sudo ntpdate time.windows.com
 7 Apr 11:26:38 ntpdate[15270]: step time server 65.55.21.13 offset -105.920608 sec
#clock should now be corrected
$ sudo service ntp start

You may need to try several servers before you find one that works! When you do it may be worth tagging this into /etc/ntp.conf