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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.
       timedatectl may be used to show the current status of systemd-
       timesyncd.service(8).
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.
       --monitor
           If timesync-status is invoked and this option is passed, then
           timedatectl monitors the status of systemd-timesyncd.service(8) and
           updates the outputs. Use Ctrl-C to terminate the monitoring.
       -a, -all
           When showing properties of systemd-timesyncd.service(8), show all
           properties regardless of whether they are set or not.
       -p, --property=
           When showing properties of systemd-timesyncd.service(8), limit
           display to certain properties as specified as argument. If not
           specified, all set properties are shown. The argument should be a
           property name, such as "ServerName". If specified more than once,
           all properties with the specified names are shown.
       --value
           When printing properties with show-timesync, only print the value,
           and skip the property name and "=".
       -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.
COMMANDS
       The following commands are understood:
       status
           Show current settings of the system clock and RTC, including
           whether network time synchronization through
           systemd-timesyncd.service is active. Even if it is inactive, a
           different service might still synchronize the clock. If no command
           is specified, this is the implied default.
       show
           Show the same information as status, but in machine readable form.
           This command is intended to be used whenever computer-parsable
           output is required. Use status if you are looking for formatted
           human-readable output.
           By default, empty properties are suppressed. Use --all to show
           those too. To select specific properties to show, use --property=.
       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 network time
           synchronization is active and enabled (if available). If the
           argument is true, this enables and starts the first existed service
           listed in the environment variable $SYSTEMD_TIMEDATED_NTP_SERVICES
           of systemd-timedated.service. If the argument is false, then this
           disables and stops the all services listed in
           $SYSTEMD_TIMEDATED_NTP_SERVICES.
   systemd-timesyncd Commands
       The following commands are specific to systemd-timesyncd.service(8).
       timesync-status
           Show current status of systemd-timesyncd.service(8). If --monitor
           is specified, then this will monitor the status updates.
       show-timesync
           Show the same information as timesync-status, but in machine
           readable form. This command is intended to be used whenever
           computer-parsable output is required. Use timesync-status if you
           are looking for formatted human-readable output.
           By default, empty properties are suppressed. Use --all to show
           those too. To select specific properties to show, use --property=.
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. If
           neither $SYSTEMD_PAGER nor $PAGER are set, a set of well-known
           pager implementations are tried in turn, including less(1) and
           more(1), until one is found. If no pager implementation is
           discovered no pager is invoked. Setting this environment variable
           to an empty string or the value "cat" is equivalent to passing
           --no-pager.
       $SYSTEMD_LESS
           Override the options passed to less (by default "FRSXMK").
       $SYSTEMD_LESSCHARSET
           Override the charset passed to less (by default "utf-8", if the
           invoking terminal is determined to be UTF-8 compatible).
       $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 disable the pager using --no-pager instead.
EXAMPLES
       Show current settings:
           $ timedatectl
                          Local time: Thu 2017-09-21 16:08:56 CEST
                      Universal time: Thu 2017-09-21 14:08:56 UTC
                            RTC time: Thu 2017-09-21 14:08:56
                           Time zone: Europe/Warsaw (CEST, +0200)
           System clock synchronized: yes
                         NTP service: active
                     RTC in local TZ: no
       Enable network time synchronization:
           $ 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 systemd-timesyncd.service
            systemd-timesyncd.service - Network Time Synchronization
              Loaded: loaded (/usr/lib/systemd/system/systemd-timesyncd.service; enabled)
              Active: active (running) since Mo 2015-03-30 14:20:38 CEST; 5s ago
                Docs: man:systemd-timesyncd.service(8)
            Main PID: 595 (systemd-timesyn)
              Status: "Using Time Server 216.239.38.15:123 (time4.google.com)."
              CGroup: /system.slice/systemd-timesyncd.service
                      595 /usr/lib/systemd/systemd-timesyncd
           ...
       Show current status of systemd-timesyncd.service(8):
           $ timedatectl timesync-status
                  Server: 216.239.38.15 (time4.google.com)
           Poll interval: 1min 4s (min: 32s; max 34min 8s)
                    Leap: normal
                 Version: 4
                 Stratum: 1
               Reference: GPS
               Precision: 1us (-20)
           Root distance: 335us (max: 5s)
                  Offset: +316us
                   Delay: 349us
                  Jitter: 0
            Packet count: 1
               Frequency: -8.802ppm
SEE ALSO
       systemd(1), hwclock(8), date(1), localtime(5), systemctl(1), systemd-
       timedated.service(8), systemd-timesyncd.service(8), systemd-
       firstboot(1)
systemd 239                                                     TIMEDATECTL(1)