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