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TIMEDATECTL(1) | timedatectl | TIMEDATECTL(1) |
NAME¶
timedatectl - Control the system time and dateSYNOPSIS¶
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-passwordDo 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,
including whether network time synchronization is on. Note that whether
network time synchronization is on simply reflects whether the
systemd-timesyncd.service unit is enabled. Even if this command shows the
status as off, a different service might still synchronize the clock with the
network.
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). This enables and starts,
or disables and stops the systemd-timesyncd.service unit. It does not affect
the state of any other, unrelated network time synchronization services that
might be installed on the system. This command is hence mostly equivalent to:
systemctl enable --now systemd-timesyncd.service and systemctl
disable --now systemd-timesyncd.service, but is protected by a different
access policy.
Note that even if time synchronization is turned off with this command, another
unrelated system service might still synchronize the clock with the network.
Also note that, strictly speaking, systemd-timesyncd.service does more than
just network time synchronization, as it ensures a monotonic clock on systems
without RTC even if no network is available. See
systemd-timesyncd.service(8) for details about this.
EXIT STATUS¶
On success, 0 is returned, a non-zero failure code otherwise.ENVIRONMENT¶
$SYSTEMD_PAGERPager 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.
$SYSTEMD_LESS
Override the default options passed to less
("FRSXMK").
EXAMPLES¶
Show current settings:$ timedatectl Local time: Di 2015-04-07 16:26:56 CEST Universal time: Di 2015-04-07 14:26:56 UTC RTC time: Di 2015-04-07 14:26:56 Time zone: Europe/Berlin (CEST, +0200) Network time on: yes NTP synchronized: yes 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 (/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 /lib/systemd/systemd-timesyncd ...
SEE ALSO¶
systemd(1), hwclock(8), date(1), localtime(5), systemctl(1), systemd-timedated.service(8), systemd-timesyncd.service(8), systemd-firstboot(1)systemd 230 |