Unable to synchronize time using NTP

the NTP socket is in use, exiting

Indicates that you have an NTP daemon running, usually the one via the ntp package. You can't have two applications adjusting the clock at the same time.

1. First stop the current NTP daemon running:

   sudo service ntp stop
   

2. Run your ntpdate command.

3. Start the NTP daemon again:

   sudo service ntp start
   

Background

The NTP daemon will not take large steps forwards or backwards, but is useful for very smooth and small transitions. Before it will work correctly, sync the time using ntpdate first, for that reason. You can query the status of the daemon like this:

ntpq -p
     remote           refid      st t when poll reach   delay   offset  jitter
==============================================================================
*chime1.surfnet. 194.171.167.130  2 u   59   64    7    3.159   -0.207   0.136
+chime2.surfnet. .GPS.            1 u   59   64    7    6.872   -0.592   0.091
[...]
 ns1.tudelft.nl  .INIT.          16 u    -   64    0    0.000    0.000   0.000
+ev001.tilaa.nl  193.67.79.202    2 u   55   64    7    4.038   -0.613   0.110

If you get the Error NTP socket in use as shown below:

In that case just run

$ sudo service ntp stop
$ sudo ntpdate pool.ntp.org
$ sudo service ntp start

and you will get

OR JUST RUN

sudo ntpdate -u pool.ntp.org

to update with the ntpd deamon running

A common problem is that people discover that their computer has not updated at the appointed DST (Daylight Saving Time) transition. Once recognized, the user attempts to correct the time with sudo ntpdate -b pool.ntp.org or similar only to discover that NTP is already running and simply didn't work.

In the general case, NTP simply cannot be trusted to correct your clock at DST transitions. For example, NTP has cases in which it will refuse to set your clock. You get tons of hits when searching for NTP problems, so clearly the limitations of NTP have affected many people. I'm sure there are solid reasons for any NTP design decision, but that doesn't change the fact that it can't be trusted to always do what the average user would expect.

Be sure to check up on it if is important to you for some specific purpose. You may have greater luck with an automatic DST transition if you manually set the correct time shortly prior to the transition.

This is a hard problem for the average user to experiment with, since DST only happens at two instances per year.