How to change system timezone in Ubuntu

The system timezone in Ubuntu is set during installation and is typically based on your location. Proper configuration of the system timezone is essential for time-dependent services like cron jobs.

Ubuntu manages timezones through the /etc/localtime file, which links to the appropriate timezone data in the /usr/share/zoneinfo directory. To change the timezone, this symbolic link must be updated to point to the correct file.

The timedatectl command is the preferred tool for managing timezones on Ubuntu systems. It allows users to check the current timezone, list available timezones, and set a new one with ease.

1. Open the terminal.
2. Check the current timezone using timedatectl.

   $ timedatectl
                  Local time: Mon 2024-05-06 19:06:41 +08
              Universal time: Mon 2024-05-06 11:06:41 UTC
                    RTC time: Mon 2024-05-06 11:06:42
                   Time zone: Asia/Kuala_Lumpur (+08, +0800)
   System clock synchronized: no
                 NTP service: active
             RTC in local TZ: no

3. List all available timezones using timedatectl.

   $ timedatectl list-timezones
   Africa/Abidjan
   Africa/Accra
   Africa/Addis_Ababa
   Africa/Algiers
   Africa/Asmara
   Africa/Asmera
   Africa/Bamako
   Africa/Bangui
   Africa/Banjul
   Africa/Bissau
   Africa/Blantyre
   Africa/Brazzaville
   Africa/Bujumbura
   Africa/Cairo
   Africa/Casablanca
   Africa/Ceuta
   Africa/Conakry
   Africa/Dakar
   Africa/Dar_es_Salaam
   Africa/Djibouti
   ##### snipped 

4. Search for the desired timezone.

   $ timedatectl list-timezones | grep -i tokyo
   Asia/Tokyo

5. Set the new timezone using timedatectl.

   $ sudo timedatectl set-timezone Asia/Tokyo
   [sudo] password for user:

   The above command is similar to doing the following two manual steps:

   1. Unlink your currently-used timezone.

      $ sudo unlink /etc/localtime
      [sudo] password for user:

   2. Link /etc/localtime to your new timezone.

      $ sudo ln -s /usr/share/zoneinfo/Asia/Tokyo /etc/localtime

6. Confirm the changes by checking the timezone again.

   $ timedatectl
                  Local time: Mon 2024-05-06 20:09:09 JST
              Universal time: Mon 2024-05-06 11:09:09 UTC
                    RTC time: Mon 2024-05-06 11:09:10
                   Time zone: Asia/Tokyo (JST, +0900)
   System clock synchronized: no
                 NTP service: active
             RTC in local TZ: no