TIMEZONE-setting waktu ubuntu 18

Getting Current Date, Time and Timezone

Time synchronization is enabled on Ubuntu 18.04 by default using systemd's timesyncd service. Use timedatectl to confirm that your system is set with time synchronization:

$ timedatectl 
                      Local time: Wed 2018-03-21 07:21:41 AEDT
                  Universal time: Tue 2018-03-20 20:21:41 UTC
                        RTC time: Tue 2018-03-20 20:21:42
                       Time zone: Australia/Sydney (AEDT, +1100)
       System clock synchronized: yes
systemd-timesyncd.service active: yes
                 RTC in local TZ: no

From the above timedatectl command output on Line 6 we can see that the Ubuntu time sync is enabled. Furthermore, Line 5 we can also see the configured timezone.

Timezone settings

In order to have an accurate time and time synchronization to work properly, the system has to be configured with the correct timezone. Set your correct timezone before proceeding further by following our How to change timezone on Ubuntu 18.04 tutorial.

Enable/Disable Time Synchronization

To turn off your Ubuntu time sync enter:

$ sudo timedatectl set-ntp off
$ timedatectl 
                      Local time: Wed 2018-03-21 07:44:53 AEDT
                  Universal time: Tue 2018-03-20 20:44:53 UTC
                        RTC time: Tue 2018-03-20 20:44:54
                       Time zone: Australia/Sydney (AEDT, +1100)
       System clock synchronized: yes
systemd-timesyncd.service active: no
                 RTC in local TZ: no

If your time synchronization is disabled, execute the following linux command to enable your Ubuntu time sync:

 $ sudo timedatectl set-ntp on

Your Ubuntu 18.04 system is now time synchronized.

---

SUBSCRIBE TO NEWSLETTER
Subscribe to Linux Career NEWSLETTER and receive latest Linux news, jobs, career advice and tutorials.

---

---

Test Time Sync on Ubuntu

The following linux commands will confirm that the time sync is set correctly.

First, use the date command to check the current date and time:

$ date
Wed 21 Mar 07:54:50 AEDT 2018

Next, with time sync enabled set an incorrect time. For example the following linux command will set the time few minutes ahead:

$ sudo date 03210800
Wed 21 Mar 08:00:00 AEDT 2018

If your time synchronization is enabled correctly the time will reset to the synced time:

$ date
Wed 21 Mar 07:55:09 AEDT 2018

Next, disable Ubuntu systemd's timesyncd service:

$ sudo timedatectl set-ntp off

Set an incorrect time, check the date and re-enable time sync:

$ sudo date 03210800
Wed 21 Mar 08:00:00 AEDT 2018
$ date
Wed 21 Mar 08:00:14 AEDT 2018
$ sudo timedatectl set-ntp on
$ date
Wed 21 Mar 07:55:45 AEDT 2018

If your time has switched back after you had re-enabled time synchronization then your Ubuntu time sync is enabled correctly.


--------------------------------------------------------------------------------------------------------------------------

Check Current Timezone Settings

Let's start by checking the current timezone settings. Use the timedatectl command to show the current timezone and time:

$ timedatectl
                      Local time: Tue 2018-06-06 10:27:34 PST
                  Universal time: Tue 2018-06-06 18:27:34 UTC
                        RTC time: Tue 2018-06-06 18:27:35
                       Time zone: Canada/Yukon (PST, -0800)
       System clock synchronized: yes
systemd-timesyncd.service active: yes
                 RTC in local TZ: no

Another alternative to check current timezone on Ubuntu 18.04 system, if the above command from some reason fails, is to check for /etc/localtime symbolic link:

$ ls -l /etc/localtime
lrwxrwxrwx 1 root root 32 Jun  6 10:27 /etc/localtime -> /usr/share/zoneinfo/Canada/Yukon

---

SUBSCRIBE TO NEWSLETTER
Subscribe to Linux Career NEWSLETTER and receive latest Linux news, jobs, career advice and tutorials.

---

---

Show all Available Timezones

In order to change timezone on Ubuntu 18.04, we first need to obtain a timezone name of the timezone we wish to change to. This is usually a CONTINENT/CITY pair.

The timedatectl command comes again handy:

$ timedatectl list-timezones

The timezone list is quite extensive. Scroll page down and up with PgDn and PgUp key respectively.

Alternatively, use grep command to narrow down your search. For example the bellow command will list all Europe cities:

$ timedatectl list-timezones | grep -i europe
Europe/Amsterdam
Europe/Andorra
Europe/Astrakhan
Europe/Athens
Europe/Belgrade
Europe/Berlin
Europe/Bratislava
Europe/Brussels
Europe/Bucharest
Europe/Budapest
Europe/Busingen
...
Europe/Zurich

NOTE:

The timedatectl command is using /usr/share/zoneinfo/ directory to generate the timezone list.

Change Timezone

Now that we know the timezone name we wish to change our timezone settings to, use timedatectl command to set a new timezone.

For example let's change timezone to Europe/Bratislava:

$ sudo timedatectl set-timezone Europe/Bratislava

Using the timedatectl command is a preferred way on how to set a timezone on Ubuntu 18.04. However, note that you can also change timezone settings manually:

NOTE:Changing the timezone using the manual method involving ln command may take minute or so to take an effect.

$ sudo unlink /etc/localtime
$ sudo ln -s /usr/share/zoneinfo/Europe/Bratislava /etc/localtime

---

---

Confirm Timezone Change

Lastly, confirm your new timezone settings:

$ timedatectl 
                      Local time: Tue 2018-06-06 19:57:17 CET
                  Universal time: Tue 2018-06-06 18:57:17 UTC
                        RTC time: Tue 2018-06-06 18:57:18
                       Time zone: Europe/Bratislava (CET, +0100)
       System clock synchronized: yes
systemd-timesyncd.service active: yes
                 RTC in local TZ: no

Alternatively, confirm a new timezone settings using ls command:

$ ls -l /etc/localtime
lrwxrwxrwx 1 root root 37 Jun  6 20:00 /etc/localtime -> /usr/share/zoneinfo/Europe/Bratislava

Change timezone from GUI

To change timezone from a default GNOME graphical user interface. Navigate to Settings-->Details-->Date & Time:

Current timezone.

Use search box to search for a city or find your timezone manually by mouse click.

New timezone is set.



---------------------------------------------------------------------------------------------------------------------

Get current zone

To see the current time zone for a session, try either of the following statements. Technically we are calling the SHOW command to display a run-time parameter.

SHOW timezone ;

…or…

SHOW time zone ;

US/Pacific

Time Zone Name

You can specify a proper time zone name. Most of these are continent/region.

SET TIME ZONE 'Africa/Casablanca';

…or…

SET TIME ZONE 'Asia/Jakarta';

Standard SQL Command

Alternatively, you can use the SQL command defined by the SQL spec: SET TIME ZONE. In this syntax a pair of words TIME ZONE replace "timezone" (actual SQL command versus parameter name), and there is no "TO".

SET TIME ZONE 'UTC';

Choose a timezone from:

SELECT * FROM pg_timezone_names;

And set as below given example:

ALTER DATABASE postgres SET timezone TO 'Europe/Berlin';

https://stackoverflow.com/questions/6663765/postgres-default-timezone