man/timedatectl.html

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  22   <a href="../libudev/index.html">gudev </a><span style="float:right">systemd 208</span><hr><div class="refentry"><a name="timedatectl"></a><div class="titlepage"></div><div class="refnamediv"><h2>Name</h2><p>timedatectl — Control the system time and date</p></div><div class="refsynopsisdiv"><h2>Synopsis</h2><div class="cmdsynopsis"><p><code class="command">timedatectl [OPTIONS...]  {COMMAND}</code> </p></div></div><div class="refsect1"><a name="idm274703814688"></a><h2 id="Description">Description<a class="headerlink" title="Permalink to this headline" href="#Description">¶</a></h2><p><span class="command"><strong>timedatectl</strong></span> may be used to
  23                 query and change the system clock and its
  24                 settings.</p></div><div class="refsect1"><a name="idm274703812832"></a><h2 id="Options">Options<a class="headerlink" title="Permalink to this headline" href="#Options">¶</a></h2><p>The following options are understood:</p><div class="variablelist"><dl class="variablelist"><dt id="-h"><span class="term"><code class="option">-h</code>, </span><span class="term"><code class="option">--help</code></span><a class="headerlink" title="Permalink to this term" href="#-h">¶</a></dt><dd><p>Prints a short help
  25                                 text and exits.</p></dd><dt id="--version"><span class="term"><code class="option">--version</code></span><a class="headerlink" title="Permalink to this term" href="#--version">¶</a></dt><dd><p>Prints a short version
  26                                 string and exits.</p></dd><dt id="--no-pager"><span class="term"><code class="option">--no-pager</code></span><a class="headerlink" title="Permalink to this term" href="#--no-pager">¶</a></dt><dd><p>Do not pipe output into a
  27                                 pager.</p></dd><dt id="--no-ask-password"><span class="term"><code class="option">--no-ask-password</code></span><a class="headerlink" title="Permalink to this term" href="#--no-ask-password">¶</a></dt><dd><p>Do not query the user
  28                                 for authentication for privileged
  29                                 operations.</p></dd><dt id="-P"><span class="term"><code class="option">-P</code>, </span><span class="term"><code class="option">--privileged</code></span><a class="headerlink" title="Permalink to this term" href="#-P">¶</a></dt><dd><p>Acquire privileges via PolicyKit
  30                                 before executing the operation.</p></dd><dt id="-H"><span class="term"><code class="option">-H</code>, </span><span class="term"><code class="option">--host</code></span><a class="headerlink" title="Permalink to this term" href="#-H">¶</a></dt><dd><p>Execute the operation
  31                                 remotely. Specify a hostname, or
  32                                 username and hostname separated by "<code class="literal">@</code>",
  33                                 to connect to. This will use SSH to
  34                                 talk to a remote
  35                                 system.</p></dd><dt id="--adjust-system-clock"><span class="term"><code class="option">--adjust-system-clock</code></span><a class="headerlink" title="Permalink to this term" href="#--adjust-system-clock">¶</a></dt><dd><p>If
  36                                 <span class="command"><strong>set-local-rtc</strong></span> is
  37                                 invoked and this option is passed, the
  38                                 system clock is synchronized from the
  39                                 RTC again, taking the new setting into
  40                                 account. Otherwise, the RTC is
  41                                 synchronized from the system
  42                                 clock.</p></dd></dl></div><p>The following commands are understood:</p><div class="variablelist"><dl class="variablelist"><dt id="status"><span class="term"><span class="command"><strong>status</strong></span></span><a class="headerlink" title="Permalink to this term" href="#status">¶</a></dt><dd><p>Show current settings
  43                                 of the system clock and
  44                                 RTC.</p></dd><dt id="set-time [TIME]"><span class="term"><span class="command"><strong>set-time [TIME]</strong></span></span><a class="headerlink" title="Permalink to this term" href="#set-time%20%5BTIME%5D">¶</a></dt><dd><p>Set the system clock
  45                                 to the specified time. This will also
  46                                 update the RTC time accordingly. The time
  47                                 may be specified in the format
  48                                 "2012-10-30
  49                                 18:17:16".</p></dd><dt id="set-timezone [TIMEZONE]"><span class="term"><span class="command"><strong>set-timezone [TIMEZONE]</strong></span></span><a class="headerlink" title="Permalink to this term" href="#set-timezone%20%5BTIMEZONE%5D">¶</a></dt><dd><p>Set the system time
  50                                 zone to the specified value. Available
  51                                 timezones can be listed with
  52                                 <span class="command"><strong>list-timezones</strong></span>. If
  53                                 the RTC is configured to be in the
  54                                 local time, this will also update the
  55                                 RTC time. This call will alter the
  56                                 <code class="filename">/etc/localtime</code>
  57                                 symlink. See
  58                                 <a href="localtime.html"><span class="citerefentry"><span class="refentrytitle">localtime</span>(5)</span></a>
  59                                 for more
  60                                 information.</p></dd><dt id="list-timezones"><span class="term"><span class="command"><strong>list-timezones</strong></span></span><a class="headerlink" title="Permalink to this term" href="#list-timezones">¶</a></dt><dd><p>List available time
  61                                 zones, one per line. Entries from the
  62                                 list can be set as the system
  63                                 timezone with
  64                                 <span class="command"><strong>set-timezone</strong></span>.</p></dd><dt id="set-local-rtc [BOOL]"><span class="term"><span class="command"><strong>set-local-rtc [BOOL]</strong></span></span><a class="headerlink" title="Permalink to this term" href="#set-local-rtc%20%5BBOOL%5D">¶</a></dt><dd><p>Takes a boolean
  65                                 argument. If "<code class="literal">0</code>", the
  66                                 system is configured to maintain the
  67                                 RTC in universal time. If
  68                                 "<code class="literal">1</code>", it will maintain
  69                                 the RTC in local time instead. Note
  70                                 that maintaining the RTC in the local
  71                                 timezone is not fully supported and
  72                                 will create various problems with time
  73                                 zone changes and daylight saving
  74                                 adjustments. If at all possible, keep the
  75                                 RTC in UTC mode. Note that invoking this
  76                                 will also synchronize the RTC from the
  77                                 system clock, unless
  78                                 <code class="option">--adjust-system-clock</code> is
  79                                 passed (see above). This command will
  80                                 change the 3rd line of
  81                                 <code class="filename">/etc/adjtime</code>, as
  82                                 documented in
  83                                 <a href="hwclock.html"><span class="citerefentry"><span class="refentrytitle">hwclock</span>(8)</span></a>.</p></dd><dt id="set-ntp [BOOL]"><span class="term"><span class="command"><strong>set-ntp [BOOL]</strong></span></span><a class="headerlink" title="Permalink to this term" href="#set-ntp%20%5BBOOL%5D">¶</a></dt><dd><p>Takes a boolean
  84                                 argument. Controls whether NTP based
  85                                 network time synchronization is
  86                                 enabled (if
  87                                 available).</p></dd></dl></div></div><div class="refsect1"><a name="idm274707674464"></a><h2 id="Exit status">Exit status<a class="headerlink" title="Permalink to this headline" href="#Exit%20status">¶</a></h2><p>On success 0 is returned, a non-zero failure
  88                 code otherwise.</p></div><div class="refsect1"><a name="idm274707673280"></a><h2 id="Environment">Environment<a class="headerlink" title="Permalink to this headline" href="#Environment">¶</a></h2><div class="variablelist"><dl class="variablelist"><dt id="$SYSTEMD_PAGER"><span class="term"><code class="varname">$SYSTEMD_PAGER</code></span><a class="headerlink" title="Permalink to this term" href="#%24SYSTEMD_PAGER">¶</a></dt><dd><p>Pager to use when
  89                                 <code class="option">--no-pager</code> is not given;
  90                                 overrides <code class="varname">$PAGER</code>.  Setting
  91                                 this to an empty string or the value
  92                                 "<code class="literal">cat</code>" is equivalent to passing
  93                                 <code class="option">--no-pager</code>.</p></dd></dl></div></div><div class="refsect1"><a name="idm274707668304"></a><h2 id="Examples">Examples<a class="headerlink" title="Permalink to this headline" href="#Examples">¶</a></h2><p>Show current settings:
  94                 </p><pre class="programlisting">
  95 $ timedatectl
  96       Local time: Fri, 2012-11-02 09:26:46 CET
  97   Universal time: Fri, 2012-11-02 08:26:46 UTC
  98         RTC time: Fri, 2012-11-02 08:26:45
  99         Timezone: Europe/Warsaw
 100       UTC offset: +0100
 101      NTP enabled: no
 102 NTP synchronized: no
 103  RTC in local TZ: no
 104       DST active: no
 105  Last DST change: CEST → CET, DST became inactive
 106                   Sun, 2012-10-28 02:59:59 CEST
 107                   Sun, 2012-10-28 02:00:00 CET
 108  Next DST change: CET → CEST, DST will become active
 109                   the clock will jump one hour forward
 110                   Sun, 2013-03-31 01:59:59 CET
 111                   Sun, 2013-03-31 03:00:00 CEST
 112                 </pre><p>
 113                 </p><p>Enable an NTP daemon (chronyd):
 114                 </p><pre class="programlisting">
 115 $ timedatectl set-ntp true
 116 ==== AUTHENTICATING FOR org.freedesktop.timedate1.set-ntp ===
 117 Authentication is required to control whether network time synchronization shall be enabled.
 118 Authenticating as: user
 119 Password: ********
 120 ==== AUTHENTICATION COMPLETE ===
 121                 </pre><p>
 122
 123                 </p><pre class="programlisting">
 124 $ systemctl status chronyd.service
 125 chronyd.service - NTP client/server
 126           Loaded: loaded (/usr/lib/systemd/system/chronyd.service; enabled)
 127           Active: active (running) since Fri, 2012-11-02 09:36:25 CET; 5s ago
 128 ...
 129                 </pre><p>
 130                 </p></div><div class="refsect1"><a name="idm274707662928"></a><h2 id="See Also">See Also<a class="headerlink" title="Permalink to this headline" href="#See%20Also">¶</a></h2><p>
 131                         <a href="systemd.html"><span class="citerefentry"><span class="refentrytitle">systemd</span>(1)</span></a>,
 132                         <a href="hwclock.html"><span class="citerefentry"><span class="refentrytitle">hwclock</span>(8)</span></a>,
 133                         <a href="date.html"><span class="citerefentry"><span class="refentrytitle">date</span>(1)</span></a>,
 134                         <a href="localtime.html"><span class="citerefentry"><span class="refentrytitle">localtime</span>(5)</span></a>,
 135                         <a href="systemctl.html"><span class="citerefentry"><span class="refentrytitle">systemctl</span>(1)</span></a>,
 136                         <a href="systemd-timedated.service.html"><span class="citerefentry"><span class="refentrytitle">systemd-timedated.service</span>(8)</span></a>
 137                 </p></div></div></body></html>