man/timedatectl.xml

   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">
   4
   5 <!--
   6   This file is part of systemd.
   7
   8   Copyright 2012 Lennart Poettering
   9
  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.
  14
  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.
  19
  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/>.
  22 -->
  23
  24 <refentry id="timedatectl" conditional='ENABLE_TIMEDATED'
  25         xmlns:xi="http://www.w3.org/2001/XInclude">
  26
  27         <refentryinfo>
  28                 <title>timedatectl</title>
  29                 <productname>systemd</productname>
  30
  31                 <authorgroup>
  32                         <author>
  33                                 <contrib>Developer</contrib>
  34                                 <firstname>Lennart</firstname>
  35                                 <surname>Poettering</surname>
  36                                 <email>lennart@poettering.net</email>
  37                         </author>
  38                 </authorgroup>
  39         </refentryinfo>
  40
  41         <refmeta>
  42                 <refentrytitle>timedatectl</refentrytitle>
  43                 <manvolnum>1</manvolnum>
  44         </refmeta>
  45
  46         <refnamediv>
  47                 <refname>timedatectl</refname>
  48                 <refpurpose>Control the system time and date</refpurpose>
  49         </refnamediv>
  50
  51         <refsynopsisdiv>
  52                 <cmdsynopsis>
  53                         <command>timedatectl <arg choice="opt" rep="repeat">OPTIONS</arg> <arg choice="req">COMMAND</arg></command>
  54                 </cmdsynopsis>
  55         </refsynopsisdiv>
  56
  57         <refsect1>
  58                 <title>Description</title>
  59
  60                 <para><command>timedatectl</command> may be used to
  61                 query and change the system clock and its
  62                 settings.</para>
  63
  64                 <para>Use
  65                 <citerefentry><refentrytitle>systemd-firstboot</refentrytitle><manvolnum>1</manvolnum></citerefentry>
  66                 to initialize the system time zone for mounted (but not
  67                 booted) system images.</para>
  68         </refsect1>
  69
  70         <refsect1>
  71                 <title>Options</title>
  72
  73                 <para>The following options are understood:</para>
  74
  75                 <variablelist>
  76                         <varlistentry>
  77                                 <term><option>--no-ask-password</option></term>
  78
  79                                 <listitem><para>Do not query the user
  80                                 for authentication for privileged
  81                                 operations.</para></listitem>
  82                         </varlistentry>
  83
  84                         <varlistentry>
  85                                 <term><option>--adjust-system-clock</option></term>
  86
  87                                 <listitem><para>If
  88                                 <command>set-local-rtc</command> is
  89                                 invoked and this option is passed, the
  90                                 system clock is synchronized from the
  91                                 RTC again, taking the new setting into
  92                                 account. Otherwise, the RTC is
  93                                 synchronized from the system
  94                                 clock.</para></listitem>
  95                         </varlistentry>
  96
  97                         <xi:include href="user-system-options.xml" xpointer="host" />
  98                         <xi:include href="user-system-options.xml" xpointer="machine" />
  99
 100                         <xi:include href="standard-options.xml" xpointer="help" />
 101                         <xi:include href="standard-options.xml" xpointer="version" />
 102                         <xi:include href="standard-options.xml" xpointer="no-pager" />
 103                 </variablelist>
 104
 105                 <para>The following commands are understood:</para>
 106
 107                 <variablelist>
 108                         <varlistentry>
 109                                 <term><command>status</command></term>
 110
 111                                 <listitem><para>Show current settings
 112                                 of the system clock and
 113                                 RTC.</para></listitem>
 114                         </varlistentry>
 115
 116                         <varlistentry>
 117                                 <term><command>set-time [TIME]</command></term>
 118
 119                                 <listitem><para>Set the system clock
 120                                 to the specified time. This will also
 121                                 update the RTC time accordingly. The time
 122                                 may be specified in the format
 123                                 "2012-10-30
 124                                 18:17:16".</para></listitem>
 125                         </varlistentry>
 126
 127                         <varlistentry>
 128                                 <term><command>set-timezone [TIMEZONE]</command></term>
 129
 130                                 <listitem><para>Set the system time
 131                                 zone to the specified value. Available
 132                                 timezones can be listed with
 133                                 <command>list-timezones</command>. If
 134                                 the RTC is configured to be in the
 135                                 local time, this will also update the
 136                                 RTC time. This call will alter the
 137                                 <filename>/etc/localtime</filename>
 138                                 symlink. See
 139                                 <citerefentry><refentrytitle>localtime</refentrytitle><manvolnum>5</manvolnum></citerefentry>
 140                                 for more
 141                                 information.</para></listitem>
 142                         </varlistentry>
 143
 144                         <varlistentry>
 145                                 <term><command>list-timezones</command></term>
 146
 147                                 <listitem><para>List available time
 148                                 zones, one per line. Entries from the
 149                                 list can be set as the system
 150                                 timezone with
 151                                 <command>set-timezone</command>.</para></listitem>
 152                         </varlistentry>
 153
 154                         <varlistentry>
 155                                 <term><command>set-local-rtc [BOOL]</command></term>
 156
 157                                 <listitem><para>Takes a boolean
 158                                 argument. If <literal>0</literal>, the
 159                                 system is configured to maintain the
 160                                 RTC in universal time. If
 161                                 <literal>1</literal>, it will maintain
 162                                 the RTC in local time instead. Note
 163                                 that maintaining the RTC in the local
 164                                 timezone is not fully supported and
 165                                 will create various problems with time
 166                                 zone changes and daylight saving
 167                                 adjustments. If at all possible, keep the
 168                                 RTC in UTC mode. Note that invoking this
 169                                 will also synchronize the RTC from the
 170                                 system clock, unless
 171                                 <option>--adjust-system-clock</option> is
 172                                 passed (see above). This command will
 173                                 change the 3rd line of
 174                                 <filename>/etc/adjtime</filename>, as
 175                                 documented in
 176                                 <citerefentry project='man-pages'><refentrytitle>hwclock</refentrytitle><manvolnum>8</manvolnum></citerefentry>.</para></listitem>
 177                         </varlistentry>
 178
 179                         <varlistentry>
 180                                 <term><command>set-ntp [BOOL]</command></term>
 181
 182                                 <listitem><para>Takes a boolean
 183                                 argument. Controls whether NTP based
 184                                 network time synchronization is
 185                                 enabled (if
 186                                 available).</para></listitem>
 187                         </varlistentry>
 188
 189                 </variablelist>
 190
 191         </refsect1>
 192
 193         <refsect1>
 194                 <title>Exit status</title>
 195
 196                 <para>On success, 0 is returned, a non-zero failure
 197                 code otherwise.</para>
 198         </refsect1>
 199
 200         <xi:include href="less-variables.xml" />
 201
 202         <refsect1>
 203                 <title>Examples</title>
 204                 <para>Show current settings:
 205                 <programlisting>$ timedatectl
 206       Local time: Fri, 2012-11-02 09:26:46 CET
 207   Universal time: Fri, 2012-11-02 08:26:46 UTC
 208         RTC time: Fri, 2012-11-02 08:26:45
 209         Timezone: Europe/Warsaw
 210       UTC offset: +0100
 211      NTP enabled: no
 212 NTP synchronized: no
 213  RTC in local TZ: no
 214       DST active: no
 215  Last DST change: CEST → CET, DST became inactive
 216                   Sun, 2012-10-28 02:59:59 CEST
 217                   Sun, 2012-10-28 02:00:00 CET
 218  Next DST change: CET → CEST, DST will become active
 219                   the clock will jump one hour forward
 220                   Sun, 2013-03-31 01:59:59 CET
 221                   Sun, 2013-03-31 03:00:00 CEST</programlisting>
 222                 </para>
 223
 224                 <para>Enable an NTP daemon (chronyd):
 225                 <programlisting>$ timedatectl set-ntp true
 226 ==== AUTHENTICATING FOR org.freedesktop.timedate1.set-ntp ===
 227 Authentication is required to control whether network time synchronization shall be enabled.
 228 Authenticating as: user
 229 Password: ********
 230 ==== AUTHENTICATION COMPLETE ===</programlisting>
 231
 232                 <programlisting>$ systemctl status chronyd.service
 233 chronyd.service - NTP client/server
 234           Loaded: loaded (/usr/lib/systemd/system/chronyd.service; enabled)
 235           Active: active (running) since Fri, 2012-11-02 09:36:25 CET; 5s ago
 236 ...</programlisting>
 237                 </para>
 238         </refsect1>
 239
 240         <refsect1>
 241                 <title>See Also</title>
 242                 <para>
 243                         <citerefentry><refentrytitle>systemd</refentrytitle><manvolnum>1</manvolnum></citerefentry>,
 244                         <citerefentry project='man-pages'><refentrytitle>hwclock</refentrytitle><manvolnum>8</manvolnum></citerefentry>,
 245                         <citerefentry project='man-pages'><refentrytitle>date</refentrytitle><manvolnum>1</manvolnum></citerefentry>,
 246                         <citerefentry><refentrytitle>localtime</refentrytitle><manvolnum>5</manvolnum></citerefentry>,
 247                         <citerefentry><refentrytitle>systemctl</refentrytitle><manvolnum>1</manvolnum></citerefentry>,
 248                         <citerefentry><refentrytitle>systemd-timedated.service</refentrytitle><manvolnum>8</manvolnum></citerefentry>,
 249                         <citerefentry><refentrytitle>systemd-firstboot</refentrytitle><manvolnum>1</manvolnum></citerefentry>
 250                 </para>
 251         </refsect1>
 252
 253 </refentry>