man/timedatectl.xml

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