timedatectl — Control the system time and date
timedatectl [OPTIONS...] {COMMAND}
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.
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
¶--version
¶--no-pager
¶Do not pipe output into a pager.
The following commands are understood:
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 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). 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.
$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).
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
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 …