Linux timedatectl Command: Check Time Zone and Time Synchronization

timedatectl checks the current time, time zone, hardware clock, and network time synchronization status of a systemd system. If necessary, it can also change the time zone or synchronization settings.

What is the timedatectl command?

The system time and the real-time clock (RTC) are different clocks. In status, you can see the local/UTC time, time zone, and synchronization status together. Since the provided synchronization services and policies may vary by distribution, do not infer the entire network connection based only on the displayed status.

Basic syntax

timedatectl [command] [argument]

The installed implementation and options may vary depending on the distribution. Check the description for your current system with man timedatectl.

Examples

Time and synchronization status

Check the display related to the current time zone and NTP synchronization.

timedatectl status

Finding available time zones

Confirm the exact time zone name before setting it.

timedatectl list-timezones

Change Time Zone

Check the time zone that complies with organizational policies, then set it.

sudo timedatectl set-timezone Asia/Seoul

Reading Time Zone and Synchronization Status

timedatectl shows local time, UTC time, time zone, and NTP synchronization status together. The following safely checks both the time zone and synchronization status.

timedatectl show -p Timezone -p NTPSynchronized

Example output:

Timezone=Asia/Seoul
NTPSynchronized=yes

NTPSynchronized=yes means that the system reports the time as synchronized, but it is not a complete diagnosis that all network time servers are functioning correctly. If the item is missing or no, check the distribution's time synchronization service and network status. Changing the time zone alters the display output, but it does not change the absolute time based on UTC.

Main Options and Format

Precautions when using

Changing the time zone can affect log display and the interpretation of scheduled tasks. Adjusting the clock directly with set-time can conflict with synchronization services, so check the NTP status first. After making changes, verify the result with timedatectl status and revert to the previous time zone if necessary.

Frequently Asked Questions

Will changing only the time zone also change the actual time?

It changes the local time representation that shows the same time. This is different from changing the actual point in time based on UTC.

Official Documentation

You can check the exact behavior of the options and implementation differences in the official documentation for timedatectl.