41

This question shows how to stop automatic time update (and switch to manual):

How to stop automatic time update?

I want to do this exact thing but I can only ssh onto my machine so I need to make this change through the terminal. Is there any way to do this?

Community
  • 1
GeneralAsh
  • 513

3 Answers3

76

GNOME Automatic Date & Time doesn't use the ntp service, installable via sudo apt-get install ntp. Therefore stopping or uninstalling the service doesn't help.

Systemd timedatectl is used, therefore one command to switch off

timedatectl set-ntp 0

and one command to switch on

timedatectl set-ntp 1

Example

enter image description here

% timedatectl set-ntp 1

enter image description here

or via timedatectl status

% timedatectl status
      Local time: Do 2015-10-08 18:17:17 CEST
  Universal time: Do 2015-10-08 16:17:17 UTC
        RTC time: Do 2015-10-08 16:17:17
       Time zone: Europe/Berlin (CEST, +0200)
     NTP enabled: no
NTP synchronized: yes
 RTC in local TZ: no
      DST active: yes
 Last DST change: DST began at
                  So 2015-03-29 01:59:59 CET
                  So 2015-03-29 03:00:00 CEST
 Next DST change: DST ends (the clock jumps one hour backwards) at
                  So 2015-10-25 02:59:59 CEST
                  So 2015-10-25 02:00:00 CET

% timedatectl set-ntp 1

% timedatectl status
      Local time: Do 2015-10-08 18:17:35 CEST
  Universal time: Do 2015-10-08 16:17:35 UTC
        RTC time: Do 2015-10-08 16:17:35
       Time zone: Europe/Berlin (CEST, +0200)
     NTP enabled: yes
NTP synchronized: yes
 RTC in local TZ: no
      DST active: yes
 Last DST change: DST began at
                  So 2015-03-29 01:59:59 CET
                  So 2015-03-29 03:00:00 CEST
 Next DST change: DST ends (the clock jumps one hour backwards) at
                  So 2015-10-25 02:59:59 CEST
                  So 2015-10-25 02:00:00 CET
A.B.
  • 90,397
  • Thank you! This is exactly what I was looking for. This is the setting that is changed when you switch between manual and automatic in the System Settings – GeneralAsh Oct 08 '15 at 16:27
  • the logs show it only synced when I restarted the service. do I need to create a cron to sync it every day? – jim smith Sep 28 '20 at 11:04
8

On a systemd operating system like Ubuntu 15.04 use the timedatectl utility, which makes the same Desktop Bus RPC calls as the GNOME control centre utility does:

timedatectl set-ntp false

Further reading

JdeBP
  • 3,959
5

What you are looking for is not ntpd which is not installed by default. It's an if-up.d script which run time update whenever a network interface activated.

  • dconf watch / shows nothing but inotifywait -m -r /etc/ will do. Here is the interesting output:

    /etc/network/if-up.d/ MOVED_FROM ntpdate
/etc/network/if-up.d/ MOVED_TO ntpdate.disabled

  • It belongs to ntpdate package.

    $ dpkg -S /etc/network/if-up.d/ntpdate
ntpdate: /etc/network/if-up.d/ntpdate

  • So to disable time update, rename that file same as the control center does:

    sudo mv /etc/network/if-up.d/ntpdate /etc/network/if-up.d/ntpdate.disabled
user.dz
  • 48,105
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    I was also irritated, dconf watch / shows a change for the timezone, but not for the automatic date/time settings. Good one =) – A.B. Oct 08 '15 at 16:27