Do not query the user for authentication for privileged operations.

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.

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.

When showing properties of systemd-timesyncd.service(8), show all properties regardless of whether they are set or not.

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.

When printing properties with show-timesync, only print the value, and skip the property name and "=".

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.

Execute operation on a local container. Specify a container name to connect to.

Print a short help text and exit.

Print a short version string and exit.

Do not pipe output into a pager.

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

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).

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.

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.

Override the options passed to less (by default "FRSXMK").

Override the charset passed to less (by default "utf-8", if the invoking terminal is determined to be UTF-8 compatible).

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.

$ 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

$ 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
...

$ 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