<?xml version='1.0'?> <!--*-nxml-*-->
<!DOCTYPE refentry PUBLIC "-//OASIS//DTD DocBook XML V4.2//EN"
- "http://www.oasis-open.org/docbook/xml/4.2/docbookx.dtd">
+ "http://www.oasis-open.org/docbook/xml/4.2/docbookx.dtd">
<!--
+ SPDX-License-Identifier: LGPL-2.1+
+
This file is part of systemd.
Copyright 2012 Lennart Poettering
along with systemd; If not, see <http://www.gnu.org/licenses/>.
-->
-<refentry id="timedatectl" conditional='ENABLE_TIMEDATED'>
-
- <refentryinfo>
- <title>timedatectl</title>
- <productname>systemd</productname>
-
- <authorgroup>
- <author>
- <contrib>Developer</contrib>
- <firstname>Lennart</firstname>
- <surname>Poettering</surname>
- <email>lennart@poettering.net</email>
- </author>
- </authorgroup>
- </refentryinfo>
-
- <refmeta>
- <refentrytitle>timedatectl</refentrytitle>
- <manvolnum>1</manvolnum>
- </refmeta>
-
- <refnamediv>
- <refname>timedatectl</refname>
- <refpurpose>Control the system time and date</refpurpose>
- </refnamediv>
-
- <refsynopsisdiv>
- <cmdsynopsis>
- <command>timedatectl <arg choice="opt" rep="repeat">OPTIONS</arg> <arg choice="req">COMMAND</arg></command>
- </cmdsynopsis>
- </refsynopsisdiv>
-
- <refsect1>
- <title>Description</title>
-
- <para><command>timedatectl</command> may be used to
- query and change the system clock and its
- settings.</para>
- </refsect1>
-
- <refsect1>
- <title>Options</title>
-
- <para>The following options are understood:</para>
-
- <variablelist>
- <varlistentry>
- <term><option>-h</option></term>
- <term><option>--help</option></term>
-
- <listitem><para>Prints a short help
- text and exits.</para></listitem>
- </varlistentry>
-
- <varlistentry>
- <term><option>--version</option></term>
-
- <listitem><para>Prints a short version
- string and exits.</para></listitem>
- </varlistentry>
-
- <varlistentry>
- <term><option>--no-pager</option></term>
-
- <listitem><para>Do not pipe output into a
- pager.</para></listitem>
- </varlistentry>
-
- <varlistentry>
- <term><option>--no-ask-password</option></term>
-
- <listitem><para>Do not query the user
- for authentication for privileged
- operations.</para></listitem>
- </varlistentry>
-
- <varlistentry>
- <term><option>-H</option></term>
- <term><option>--host=</option></term>
-
- <listitem><para>Execute operation
- remotely. Specify a hostname, or
- username and hostname separated by <literal>@</literal>,
- to connect to. This will use SSH to
- talk to the remote machine manager
- instance.</para></listitem>
- </varlistentry>
-
- <varlistentry>
- <term><option>-M</option></term>
- <term><option>--machine=</option></term>
-
- <listitem><para>Execute operation on a
- local container. Specify a container
- name to connect to.</para></listitem>
- </varlistentry>
-
- <varlistentry>
- <term><option>--adjust-system-clock</option></term>
-
- <listitem><para>If
- <command>set-local-rtc</command> 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.</para></listitem>
- </varlistentry>
- </variablelist>
-
- <para>The following commands are understood:</para>
-
- <variablelist>
- <varlistentry>
- <term><command>status</command></term>
-
- <listitem><para>Show current settings
- of the system clock and
- RTC.</para></listitem>
- </varlistentry>
-
- <varlistentry>
- <term><command>set-time [TIME]</command></term>
-
- <listitem><para>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".</para></listitem>
- </varlistentry>
-
- <varlistentry>
- <term><command>set-timezone [TIMEZONE]</command></term>
-
- <listitem><para>Set the system time
- zone to the specified value. Available
- timezones can be listed with
- <command>list-timezones</command>. If
- the RTC is configured to be in the
- local time, this will also update the
- RTC time. This call will alter the
- <filename>/etc/localtime</filename>
- symlink. See
- <citerefentry><refentrytitle>localtime</refentrytitle><manvolnum>5</manvolnum></citerefentry>
- for more
- information.</para></listitem>
- </varlistentry>
-
- <varlistentry>
- <term><command>list-timezones</command></term>
-
- <listitem><para>List available time
- zones, one per line. Entries from the
- list can be set as the system
- timezone with
- <command>set-timezone</command>.</para></listitem>
- </varlistentry>
-
- <varlistentry>
- <term><command>set-local-rtc [BOOL]</command></term>
-
- <listitem><para>Takes a boolean
- argument. If <literal>0</literal>, the
- system is configured to maintain the
- RTC in universal time. If
- <literal>1</literal>, 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
- <option>--adjust-system-clock</option> is
- passed (see above). This command will
- change the 3rd line of
- <filename>/etc/adjtime</filename>, as
- documented in
- <citerefentry><refentrytitle>hwclock</refentrytitle><manvolnum>8</manvolnum></citerefentry>.</para></listitem>
- </varlistentry>
-
- <varlistentry>
- <term><command>set-ntp [BOOL]</command></term>
-
- <listitem><para>Takes a boolean
- argument. Controls whether NTP based
- network time synchronization is
- enabled (if
- available).</para></listitem>
- </varlistentry>
-
- </variablelist>
-
- </refsect1>
-
- <refsect1>
- <title>Exit status</title>
-
- <para>On success 0 is returned, a non-zero failure
- code otherwise.</para>
- </refsect1>
-
- <refsect1>
- <title>Environment</title>
-
- <variablelist class='environment-variables'>
- <varlistentry>
- <term><varname>$SYSTEMD_PAGER</varname></term>
- <listitem><para>Pager to use when
- <option>--no-pager</option> is not given;
- overrides <varname>$PAGER</varname>. Setting
- this to an empty string or the value
- <literal>cat</literal> is equivalent to passing
- <option>--no-pager</option>.</para></listitem>
- </varlistentry>
- </variablelist>
- </refsect1>
-
- <refsect1>
- <title>Examples</title>
- <para>Show current settings:
- <programlisting>
-$ 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
- </programlisting>
- </para>
-
- <para>Enable an NTP daemon (chronyd):
- <programlisting>
-$ timedatectl set-ntp true
+<refentry id="timedatectl" conditional='ENABLE_TIMEDATED'
+ xmlns:xi="http://www.w3.org/2001/XInclude">
+
+ <refentryinfo>
+ <title>timedatectl</title>
+ <productname>systemd</productname>
+
+ <authorgroup>
+ <author>
+ <contrib>Developer</contrib>
+ <firstname>Lennart</firstname>
+ <surname>Poettering</surname>
+ <email>lennart@poettering.net</email>
+ </author>
+ </authorgroup>
+ </refentryinfo>
+
+ <refmeta>
+ <refentrytitle>timedatectl</refentrytitle>
+ <manvolnum>1</manvolnum>
+ </refmeta>
+
+ <refnamediv>
+ <refname>timedatectl</refname>
+ <refpurpose>Control the system time and date</refpurpose>
+ </refnamediv>
+
+ <refsynopsisdiv>
+ <cmdsynopsis>
+ <command>timedatectl <arg choice="opt" rep="repeat">OPTIONS</arg> <arg choice="req">COMMAND</arg></command>
+ </cmdsynopsis>
+ </refsynopsisdiv>
+
+ <refsect1>
+ <title>Description</title>
+
+ <para><command>timedatectl</command> may be used to query and
+ change the system clock and its settings.</para>
+
+ <para>Use
+ <citerefentry><refentrytitle>systemd-firstboot</refentrytitle><manvolnum>1</manvolnum></citerefentry>
+ to initialize the system time zone for mounted (but not booted)
+ system images.</para>
+ </refsect1>
+
+ <refsect1>
+ <title>Options</title>
+
+ <para>The following options are understood:</para>
+
+ <variablelist>
+ <varlistentry>
+ <term><option>--no-ask-password</option></term>
+
+ <listitem><para>Do not query the user for authentication for
+ privileged operations.</para></listitem>
+ </varlistentry>
+
+ <varlistentry>
+ <term><option>--adjust-system-clock</option></term>
+
+ <listitem><para>If <command>set-local-rtc</command> 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.</para></listitem>
+ </varlistentry>
+
+ <xi:include href="user-system-options.xml" xpointer="host" />
+ <xi:include href="user-system-options.xml" xpointer="machine" />
+
+ <xi:include href="standard-options.xml" xpointer="help" />
+ <xi:include href="standard-options.xml" xpointer="version" />
+ <xi:include href="standard-options.xml" xpointer="no-pager" />
+ </variablelist>
+
+ <para>The following commands are understood:</para>
+
+ <variablelist>
+ <varlistentry>
+ <term><command>status</command></term>
+
+ <listitem><para>Show current settings of the system clock and RTC,
+ including whether network time synchronization through
+ <filename>systemd-timesyncd.service</filename> is active. Even if it is
+ inactive, a different service might still synchronize the clock.
+ </para></listitem>
+ </varlistentry>
+
+ <varlistentry>
+ <term><command>set-time [TIME]</command></term>
+
+ <listitem><para>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".</para></listitem>
+ </varlistentry>
+
+ <varlistentry>
+ <term><command>set-timezone [TIMEZONE]</command></term>
+
+ <listitem><para>Set the system time zone to the specified
+ value. Available timezones can be listed with
+ <command>list-timezones</command>. If the RTC is configured to
+ be in the local time, this will also update the RTC time. This
+ call will alter the <filename>/etc/localtime</filename>
+ symlink. See
+ <citerefentry><refentrytitle>localtime</refentrytitle><manvolnum>5</manvolnum></citerefentry>
+ for more information.</para></listitem>
+ </varlistentry>
+
+ <varlistentry>
+ <term><command>list-timezones</command></term>
+
+ <listitem><para>List available time zones, one per line.
+ Entries from the list can be set as the system timezone with
+ <command>set-timezone</command>.</para></listitem>
+ </varlistentry>
+
+ <varlistentry>
+ <term><command>set-local-rtc [BOOL]</command></term>
+
+ <listitem><para>Takes a boolean argument. If
+ <literal>0</literal>, the system is configured to maintain the
+ RTC in universal time. If <literal>1</literal>, 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
+ <option>--adjust-system-clock</option> is passed (see above).
+ This command will change the 3rd line of
+ <filename>/etc/adjtime</filename>, as documented in
+ <citerefentry project='man-pages'><refentrytitle>hwclock</refentrytitle><manvolnum>8</manvolnum></citerefentry>.
+ </para></listitem>
+ </varlistentry>
+
+ <varlistentry>
+ <term><command>set-ntp [BOOL]</command></term>
+
+ <listitem><para>Takes a boolean argument. Controls whether
+ network time synchronization is active and enabled (if
+ available). This enables and starts, or disables and stops the
+ <filename>systemd-timesyncd.service</filename> 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:
+ <command>systemctl enable --now
+ systemd-timesyncd.service</command> and <command>systemctl
+ disable --now systemd-timesyncd.service</command>, but is
+ protected by a different access policy.</para>
+
+ <para>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,
+ <filename>systemd-timesyncd.service</filename> does more than
+ just network time synchronization, as it ensures a monotonic
+ clock on systems without RTC even if no network is
+ available. See
+ <citerefentry><refentrytitle>systemd-timesyncd.service</refentrytitle><manvolnum>8</manvolnum></citerefentry>
+ for details about this.</para></listitem>
+ </varlistentry>
+
+ </variablelist>
+
+ </refsect1>
+
+ <refsect1>
+ <title>Exit status</title>
+
+ <para>On success, 0 is returned, a non-zero failure
+ code otherwise.</para>
+ </refsect1>
+
+ <xi:include href="less-variables.xml" />
+
+ <refsect1>
+ <title>Examples</title>
+ <para>Show current settings:
+ <programlisting>$ 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
+systemd-timesyncd.service active: yes
+ RTC in local TZ: no</programlisting>
+ </para>
+
+ <para>Enable network time synchronization:
+ <programlisting>$ 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 ===
- </programlisting>
-
- <programlisting>
-$ 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
-...
- </programlisting>
- </para>
- </refsect1>
-
- <refsect1>
- <title>See Also</title>
- <para>
- <citerefentry><refentrytitle>systemd</refentrytitle><manvolnum>1</manvolnum></citerefentry>,
- <citerefentry><refentrytitle>hwclock</refentrytitle><manvolnum>8</manvolnum></citerefentry>,
- <citerefentry><refentrytitle>date</refentrytitle><manvolnum>1</manvolnum></citerefentry>,
- <citerefentry><refentrytitle>localtime</refentrytitle><manvolnum>5</manvolnum></citerefentry>,
- <citerefentry><refentrytitle>systemctl</refentrytitle><manvolnum>1</manvolnum></citerefentry>,
- <citerefentry><refentrytitle>systemd-timedated.service</refentrytitle><manvolnum>8</manvolnum></citerefentry>
- </para>
- </refsect1>
+==== AUTHENTICATION COMPLETE ===</programlisting>
+
+ <programlisting>$ 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
+…</programlisting>
+ </para>
+ </refsect1>
+
+ <refsect1>
+ <title>See Also</title>
+ <para>
+ <citerefentry><refentrytitle>systemd</refentrytitle><manvolnum>1</manvolnum></citerefentry>,
+ <citerefentry project='man-pages'><refentrytitle>hwclock</refentrytitle><manvolnum>8</manvolnum></citerefentry>,
+ <citerefentry project='man-pages'><refentrytitle>date</refentrytitle><manvolnum>1</manvolnum></citerefentry>,
+ <citerefentry><refentrytitle>localtime</refentrytitle><manvolnum>5</manvolnum></citerefentry>,
+ <citerefentry><refentrytitle>systemctl</refentrytitle><manvolnum>1</manvolnum></citerefentry>,
+ <citerefentry><refentrytitle>systemd-timedated.service</refentrytitle><manvolnum>8</manvolnum></citerefentry>,
+ <citerefentry><refentrytitle>systemd-timesyncd.service</refentrytitle><manvolnum>8</manvolnum></citerefentry>,
+ <citerefentry><refentrytitle>systemd-firstboot</refentrytitle><manvolnum>1</manvolnum></citerefentry>
+ </para>
+ </refsect1>
</refentry>