<?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"> <!-- This file is part of systemd. Copyright 2012 Lennart Poettering systemd is free software; you can redistribute it and/or modify it under the terms of the GNU Lesser General Public License as published by the Free Software Foundation; either version 2.1 of the License, or (at your option) any later version. systemd is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU Lesser General Public License for more details. You should have received a copy of the GNU Lesser General Public License 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>Don't 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 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.</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 time zones 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 time zone 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 time zone is not fully supported and will create various problems with time zone changes and daylight saving adjustments. If at all possible use RTC in UTC. 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 ==== 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> </refentry>