systemd/man/timedatectl.1

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.TH "TIMEDATECTL" "1" "" "systemd 208" "timedatectl"
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.SH "NAME"
timedatectl \- Control the system time and date
.SH "SYNOPSIS"
.HP \w'\fBtimedatectl\ \fR\fB[OPTIONS...]\fR\fB\ \fR\fB{COMMAND}\fR\ 'u
\fBtimedatectl \fR\fB[OPTIONS...]\fR\fB \fR\fB{COMMAND}\fR
.SH "DESCRIPTION"
.PP
\fBtimedatectl\fR
may be used to query and change the system clock and its settings\&.
.SH "OPTIONS"
.PP
The following options are understood:
.PP
\fB\-h\fR, \fB\-\-help\fR
.RS 4
Prints a short help text and exits\&.
.RE
.PP
\fB\-\-version\fR
.RS 4
Prints a short version string and exits\&.
.RE
.PP
\fB\-\-no\-pager\fR
.RS 4
Do not pipe output into a pager\&.
.RE
.PP
\fB\-\-no\-ask\-password\fR
.RS 4
Do not query the user for authentication for privileged operations\&.
.RE
.PP
\fB\-P\fR, \fB\-\-privileged\fR
.RS 4
Acquire privileges via PolicyKit before executing the operation\&.
.RE
.PP
\fB\-H\fR, \fB\-\-host\fR
.RS 4
Execute the operation remotely\&. Specify a hostname, or username and hostname separated by
"@", to connect to\&. This will use SSH to talk to a remote system\&.
.RE
.PP
\fB\-\-adjust\-system\-clock\fR
.RS 4
If
\fBset\-local\-rtc\fR
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\&.
.RE
.PP
The following commands are understood:
.PP
\fBstatus\fR
.RS 4
Show current settings of the system clock and RTC\&.
.RE
.PP
\fBset\-time [TIME]\fR
.RS 4
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"\&.
.RE
.PP
\fBset\-timezone [TIMEZONE]\fR
.RS 4
Set the system time zone to the specified value\&. Available timezones can be listed with
\fBlist\-timezones\fR\&. 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
\fBlocaltime\fR(5)
for more information\&.
.RE
.PP
\fBlist\-timezones\fR
.RS 4
List available time zones, one per line\&. Entries from the list can be set as the system timezone with
\fBset\-timezone\fR\&.
.RE
.PP
\fBset\-local\-rtc [BOOL]\fR
.RS 4
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
\fB\-\-adjust\-system\-clock\fR
is passed (see above)\&. This command will change the 3rd line of
/etc/adjtime, as documented in
\fBhwclock\fR(8)\&.
.RE
.PP
\fBset\-ntp [BOOL]\fR
.RS 4
Takes a boolean argument\&. Controls whether NTP based network time synchronization is enabled (if available)\&.
.RE
.SH "EXIT STATUS"
.PP
On success 0 is returned, a non\-zero failure code otherwise\&.
.SH "ENVIRONMENT"
.PP
\fI$SYSTEMD_PAGER\fR
.RS 4
Pager to use when
\fB\-\-no\-pager\fR
is not given; overrides
\fI$PAGER\fR\&. Setting this to an empty string or the value
"cat"
is equivalent to passing
\fB\-\-no\-pager\fR\&.
.RE
.SH "EXAMPLES"
.PP
Show current settings:
.sp
.if n \{\
.RS 4
.\}
.nf
$ timedatectl
      Local time: Fri, 2012\-11\-02 09:26:46 CET
  Universal time: Fri, 2012\-11\-02 08:26:46 UTC
        RTC time: Fri, 2012\-11\-02 08:26:45
        Timezone: Europe/Warsaw
      UTC offset: +0100
     NTP enabled: no
NTP synchronized: no
 RTC in local TZ: no
      DST active: no
 Last DST change: CEST → CET, DST became inactive
                  Sun, 2012\-10\-28 02:59:59 CEST
                  Sun, 2012\-10\-28 02:00:00 CET
 Next DST change: CET → CEST, DST will become active
                  the clock will jump one hour forward
                  Sun, 2013\-03\-31 01:59:59 CET
                  Sun, 2013\-03\-31 03:00:00 CEST
                
.fi
.if n \{\
.RE
.\}
.PP
Enable an NTP daemon (chronyd):
.sp
.if n \{\
.RS 4
.\}
.nf
$ 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 ===
                
.fi
.if n \{\
.RE
.\}
.sp
.if n \{\
.RS 4
.\}
.nf
$ systemctl status chronyd\&.service
chronyd\&.service \- NTP client/server
          Loaded: loaded (/usr/lib/systemd/system/chronyd\&.service; enabled)
          Active: active (running) since Fri, 2012\-11\-02 09:36:25 CET; 5s ago
\&.\&.\&.
                
.fi
.if n \{\
.RE
.\}
.sp
.SH "SEE ALSO"
.PP
\fBsystemd\fR(1),
\fBhwclock\fR(8),
\fBdate\fR(1),
\fBlocaltime\fR(5),
\fBsystemctl\fR(1),
\fBsystemd-timedated.service\fR(8)