Ubuntu Manpages

timedatectl

Control the system time and date

timedatectl [OPTIONS...] {COMMAND}

timedatectl may be used to query and change the system clock and its settings.

The following options are understood:

-h, --help

Prints a short help text and exits.

--version

Prints a short version string and exits.

--no-pager

Do not pipe output into a pager.

--no-ask-password

Don't query the user for authentication for privileged operations.

-H, --host

Execute the operation remotely. Specify a hostname, or username and hostname separated by @, to connect to. This will use SSH to talk to a remote system.

--adjust-system-clock

If set-local-rtc is invoked and this option is passed the system clock is synchronized from the RTC again, taking the new setting into account. Otherwise the RTC is synchronized from the system clock.

The following commands are understood:

status

Show current settings of the system clock and RTC.

set-time [TIME]

Set the system clock to the specified time. This will also update the RTC time accordingly. The time may be specified in the format "2012-10-30 18:17:16".

set-timezone [TIMEZONE]

Set the system time zone to the specified value. Available time zones can be listed with list-timezones. If the RTC is configured to be in the local time this will also update the RTC time. This call will alter the /etc/localtime symlink. See localtime(5) for more information.

list-timezones

List available time zones, one per line. Entries from the list can be set as the system time zone with set-timezone.

set-local-rtc [BOOL]

Takes a boolean argument. If 0 the system is configured to maintain the RTC in universal time, if 1 it will maintain the RTC in local time instead. Note that maintaining the RTC in the local time zone is not fully supported and will create various problems with time zone changes and daylight saving adjustments. If at all possible use RTC in UTC. Note that invoking this will also synchronize the RTC from the system clock, unless --adjust-system-clock is passed (see above). This command will change the 3rd line of /etc/adjtime, as documented in hwclock(8).

set-ntp [BOOL]

Takes a boolean argument. Controls whether NTP based network time synchronization is enabled (if available).

On success 0 is returned, a non-zero failure code otherwise.

$SYSTEMD_PAGER

Pager to use when --no-pager is not given; overrides $PAGER. Setting this to an empty string or the value cat is equivalent to passing --no-pager.

Show current settings:

$ timedatectl
      Local time: Fri, 2012-11-02 09:26:46 CET
  Universal time: Fri, 2012-11-02 08:26:46 UTC
        RTC time: Fri, 2012-11-02 08:26:45
        Timezone: Europe/Warsaw
      UTC offset: +0100
     NTP enabled: no
NTP synchronized: no
 RTC in local TZ: no
      DST active: no
 Last DST change: CEST → CET, DST became inactive
                  Sun, 2012-10-28 02:59:59 CEST
                  Sun, 2012-10-28 02:00:00 CET
 Next DST change: CET → CEST, DST will become active
                  the clock will jump one hour forward
                  Sun, 2013-03-31 01:59:59 CET
                  Sun, 2013-03-31 03:00:00 CEST

Enable an NTP daemon (chronyd):

$ timedatectl set-ntp true
==== AUTHENTICATING FOR org.freedesktop.timedate1.set-ntp ===
Authentication is required to control whether network time synchronization shall be enabled.
Authenticating as: user
Password: ********
==== AUTHENTICATION COMPLETE ===
                

$ systemctl status chronyd.service
chronyd.service - NTP client/server
          Loaded: loaded (/usr/lib/systemd/system/chronyd.service; enabled)
          Active: active (running) since Fri, 2012-11-02 09:36:25 CET; 5s ago
...

systemd(1), hwclock(8), date(1), localtime(5), systemctl(1), systemd-timedated.service(8)