1 <?xml version='1.0'?> <!--*-nxml-*-->
2 <!DOCTYPE refentry PUBLIC "-//OASIS//DTD DocBook XML V4.2//EN"
3 "http://www.oasis-open.org/docbook/xml/4.2/docbookx.dtd">
6 This file is part of systemd.
8 Copyright 2012 Lennart Poettering
10 systemd is free software; you can redistribute it and/or modify it
11 under the terms of the GNU Lesser General Public License as published by
12 the Free Software Foundation; either version 2.1 of the License, or
13 (at your option) any later version.
15 systemd is distributed in the hope that it will be useful, but
16 WITHOUT ANY WARRANTY; without even the implied warranty of
17 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
18 Lesser General Public License for more details.
20 You should have received a copy of the GNU Lesser General Public License
21 along with systemd; If not, see <http://www.gnu.org/licenses/>.
24 <refentry id="timedatectl" conditional='ENABLE_TIMEDATED'
25 xmlns:xi="http://www.w3.org/2001/XInclude">
28 <title>timedatectl</title>
29 <productname>systemd</productname>
33 <contrib>Developer</contrib>
34 <firstname>Lennart</firstname>
35 <surname>Poettering</surname>
36 <email>lennart@poettering.net</email>
42 <refentrytitle>timedatectl</refentrytitle>
43 <manvolnum>1</manvolnum>
47 <refname>timedatectl</refname>
48 <refpurpose>Control the system time and date</refpurpose>
53 <command>timedatectl <arg choice="opt" rep="repeat">OPTIONS</arg> <arg choice="req">COMMAND</arg></command>
58 <title>Description</title>
60 <para><command>timedatectl</command> may be used to
61 query and change the system clock and its
66 <title>Options</title>
68 <para>The following options are understood:</para>
72 <term><option>-h</option></term>
73 <term><option>--help</option></term>
75 <listitem><para>Prints a short help
76 text and exits.</para></listitem>
80 <term><option>--version</option></term>
82 <listitem><para>Prints a short version
83 string and exits.</para></listitem>
87 <term><option>--no-pager</option></term>
89 <listitem><para>Do not pipe output into a
90 pager.</para></listitem>
94 <term><option>--no-ask-password</option></term>
96 <listitem><para>Do not query the user
97 for authentication for privileged
98 operations.</para></listitem>
102 <term><option>-H</option></term>
103 <term><option>--host=</option></term>
105 <listitem><para>Execute the operation
106 remotely. Specify a hostname, or
107 username and hostname separated by <literal>@</literal>,
108 to connect to. This will use SSH to
109 talk to the remote machine manager
110 instance.</para></listitem>
114 <term><option>-M</option></term>
115 <term><option>--machine=</option></term>
117 <listitem><para>Execute operation on a
118 local container. Specify a container
119 name to connect to.</para></listitem>
123 <term><option>--adjust-system-clock</option></term>
126 <command>set-local-rtc</command> is
127 invoked and this option is passed, the
128 system clock is synchronized from the
129 RTC again, taking the new setting into
130 account. Otherwise, the RTC is
131 synchronized from the system
132 clock.</para></listitem>
136 <para>The following commands are understood:</para>
140 <term><command>status</command></term>
142 <listitem><para>Show current settings
143 of the system clock and
144 RTC.</para></listitem>
148 <term><command>set-time [TIME]</command></term>
150 <listitem><para>Set the system clock
151 to the specified time. This will also
152 update the RTC time accordingly. The time
153 may be specified in the format
155 18:17:16".</para></listitem>
159 <term><command>set-timezone [TIMEZONE]</command></term>
161 <listitem><para>Set the system time
162 zone to the specified value. Available
163 timezones can be listed with
164 <command>list-timezones</command>. If
165 the RTC is configured to be in the
166 local time, this will also update the
167 RTC time. This call will alter the
168 <filename>/etc/localtime</filename>
170 <citerefentry><refentrytitle>localtime</refentrytitle><manvolnum>5</manvolnum></citerefentry>
172 information.</para></listitem>
176 <term><command>list-timezones</command></term>
178 <listitem><para>List available time
179 zones, one per line. Entries from the
180 list can be set as the system
182 <command>set-timezone</command>.</para></listitem>
186 <term><command>set-local-rtc [BOOL]</command></term>
188 <listitem><para>Takes a boolean
189 argument. If <literal>0</literal>, the
190 system is configured to maintain the
191 RTC in universal time. If
192 <literal>1</literal>, it will maintain
193 the RTC in local time instead. Note
194 that maintaining the RTC in the local
195 timezone is not fully supported and
196 will create various problems with time
197 zone changes and daylight saving
198 adjustments. If at all possible, keep the
199 RTC in UTC mode. Note that invoking this
200 will also synchronize the RTC from the
202 <option>--adjust-system-clock</option> is
203 passed (see above). This command will
204 change the 3rd line of
205 <filename>/etc/adjtime</filename>, as
207 <citerefentry><refentrytitle>hwclock</refentrytitle><manvolnum>8</manvolnum></citerefentry>.</para></listitem>
211 <term><command>set-ntp [BOOL]</command></term>
213 <listitem><para>Takes a boolean
214 argument. Controls whether NTP based
215 network time synchronization is
217 available).</para></listitem>
225 <title>Exit status</title>
227 <para>On success, 0 is returned, a non-zero failure
228 code otherwise.</para>
231 <xi:include href="less-variables.xml" />
234 <title>Examples</title>
235 <para>Show current settings:
238 Local time: Fri, 2012-11-02 09:26:46 CET
239 Universal time: Fri, 2012-11-02 08:26:46 UTC
240 RTC time: Fri, 2012-11-02 08:26:45
241 Timezone: Europe/Warsaw
247 Last DST change: CEST → CET, DST became inactive
248 Sun, 2012-10-28 02:59:59 CEST
249 Sun, 2012-10-28 02:00:00 CET
250 Next DST change: CET → CEST, DST will become active
251 the clock will jump one hour forward
252 Sun, 2013-03-31 01:59:59 CET
253 Sun, 2013-03-31 03:00:00 CEST
257 <para>Enable an NTP daemon (chronyd):
259 $ timedatectl set-ntp true
260 ==== AUTHENTICATING FOR org.freedesktop.timedate1.set-ntp ===
261 Authentication is required to control whether network time synchronization shall be enabled.
262 Authenticating as: user
264 ==== AUTHENTICATION COMPLETE ===
268 $ systemctl status chronyd.service
269 chronyd.service - NTP client/server
270 Loaded: loaded (/usr/lib/systemd/system/chronyd.service; enabled)
271 Active: active (running) since Fri, 2012-11-02 09:36:25 CET; 5s ago
278 <title>See Also</title>
280 <citerefentry><refentrytitle>systemd</refentrytitle><manvolnum>1</manvolnum></citerefentry>,
281 <citerefentry><refentrytitle>hwclock</refentrytitle><manvolnum>8</manvolnum></citerefentry>,
282 <citerefentry><refentrytitle>date</refentrytitle><manvolnum>1</manvolnum></citerefentry>,
283 <citerefentry><refentrytitle>localtime</refentrytitle><manvolnum>5</manvolnum></citerefentry>,
284 <citerefentry><refentrytitle>systemctl</refentrytitle><manvolnum>1</manvolnum></citerefentry>,
285 <citerefentry><refentrytitle>systemd-timedated.service</refentrytitle><manvolnum>8</manvolnum></citerefentry>