Ubuntu Manpage: timedatectl - Control the system time and date

Provided by: systemd-services_204-5ubuntu20.31_amd64

NAME

       timedatectl - Control the system time and date

SYNOPSIS


       timedatectl [OPTIONS...] {COMMAND}

DESCRIPTION

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

OPTIONS

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).

EXIT STATUS

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

ENVIRONMENT

       $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.

EXAMPLES

       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
           ...