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TIMEDATECTL(1)                    timedatectl                   TIMEDATECTL(1)

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.
       Use systemd-firstboot(1) to initialize the system time zone for mounted
       (but not booted) system images.
OPTIONS
       The following options are understood:
       --no-ask-password
           Do not query the user for authentication for privileged operations.
       --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.
       -H, --host=
           Execute the operation remotely. Specify a hostname, or a username
           and hostname separated by "@", to connect to. The hostname may
           optionally be suffixed by a container name, separated by ":", which
           connects directly to a specific container on the specified host.
           This will use SSH to talk to the remote machine manager instance.
           Container names may be enumerated with machinectl -H HOST.
       -M, --machine=
           Execute operation on a local container. Specify a container name to
           connect to.
       -h, --help
           Print a short help text and exit.
       --version
           Print a short version string and exit.
       --no-pager
           Do not pipe output into a pager.
       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
           timezones 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 timezone 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 timezone is not fully supported and will create various
           problems with time zone changes and daylight saving adjustments. If
           at all possible, keep the RTC in UTC mode. 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.
       $SYSTEMD_LESS
           Override the default options passed to less ("FRSXMK").
       $SYSTEMD_PAGERSECURE
           Takes a boolean argument. When true, the "secure" mode of the pager
           is enabled; if false, disabled. If $SYSTEMD_PAGERSECURE is not set
           at all, secure mode is enabled if the effective UID is not the same
           as the owner of the login session, see geteuid(2) and
           sd_pid_get_owner_uid(3). In secure mode, LESSSECURE=1 will be set
           when invoking the pager, and the pager shall disable commands that
           open or create new files or start new subprocesses. When
           $SYSTEMD_PAGERSECURE is not set at all, pagers which are not known
           to implement secure mode will not be used. (Currently only less(1)
           implements secure mode.)
           Note: when commands are invoked with elevated privileges, for
           example under sudo(8) or pkexec(1), care must be taken to ensure
           that unintended interactive features are not enabled. "Secure" mode
           for the pager may be enabled automatically as describe above.
           Setting SYSTEMD_PAGERSECURE=0 or not removing it from the inherited
           environment allows the user to invoke arbitrary commands. Note that
           if the $SYSTEMD_PAGER or $PAGER variables are to be honoured,
           $SYSTEMD_PAGERSECURE must be set too. It might be reasonable to
           completly isable the pager using --no-pager instead.
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
           ...

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

systemd 219                                                     TIMEDATECTL(1)