man/timedatectl.xml

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  11   Copyright 2012 Lennart Poettering
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  26
  27 <refentry id="timedatectl" conditional='ENABLE_TIMEDATED'
  28   xmlns:xi="http://www.w3.org/2001/XInclude">
  29
  30   <refentryinfo>
  31     <title>timedatectl</title>
  32     <productname>systemd</productname>
  33
  34     <authorgroup>
  35       <author>
  36         <contrib>Developer</contrib>
  37         <firstname>Lennart</firstname>
  38         <surname>Poettering</surname>
  39         <email>lennart@poettering.net</email>
  40       </author>
  41     </authorgroup>
  42   </refentryinfo>
  43
  44   <refmeta>
  45     <refentrytitle>timedatectl</refentrytitle>
  46     <manvolnum>1</manvolnum>
  47   </refmeta>
  48
  49   <refnamediv>
  50     <refname>timedatectl</refname>
  51     <refpurpose>Control the system time and date</refpurpose>
  52   </refnamediv>
  53
  54   <refsynopsisdiv>
  55     <cmdsynopsis>
  56       <command>timedatectl <arg choice="opt" rep="repeat">OPTIONS</arg> <arg choice="req">COMMAND</arg></command>
  57     </cmdsynopsis>
  58   </refsynopsisdiv>
  59
  60   <refsect1>
  61     <title>Description</title>
  62
  63     <para><command>timedatectl</command> may be used to query and
  64     change the system clock and its settings.</para>
  65
  66     <para>Use
  67     <citerefentry><refentrytitle>systemd-firstboot</refentrytitle><manvolnum>1</manvolnum></citerefentry>
  68     to initialize the system time zone for mounted (but not booted)
  69     system images.</para>
  70   </refsect1>
  71
  72   <refsect1>
  73     <title>Options</title>
  74
  75     <para>The following options are understood:</para>
  76
  77     <variablelist>
  78       <varlistentry>
  79         <term><option>--no-ask-password</option></term>
  80
  81         <listitem><para>Do not query the user for authentication for
  82         privileged operations.</para></listitem>
  83       </varlistentry>
  84
  85       <varlistentry>
  86         <term><option>--adjust-system-clock</option></term>
  87
  88         <listitem><para>If <command>set-local-rtc</command> is invoked
  89         and this option is passed, the system clock is synchronized
  90         from the RTC again, taking the new setting into account.
  91         Otherwise, the RTC is synchronized from the system
  92         clock.</para></listitem>
  93       </varlistentry>
  94
  95       <xi:include href="user-system-options.xml" xpointer="host" />
  96       <xi:include href="user-system-options.xml" xpointer="machine" />
  97
  98       <xi:include href="standard-options.xml" xpointer="help" />
  99       <xi:include href="standard-options.xml" xpointer="version" />
 100       <xi:include href="standard-options.xml" xpointer="no-pager" />
 101     </variablelist>
 102
 103     <para>The following commands are understood:</para>
 104
 105     <variablelist>
 106       <varlistentry>
 107         <term><command>status</command></term>
 108
 109         <listitem><para>Show current settings of the system clock and
 110         RTC, including whether network time synchronization is
 111         on. Note that whether network time synchronization is on
 112         simply reflects whether the
 113         <filename>systemd-timesyncd.service</filename> unit is
 114         enabled. Even if this command shows the status as off a
 115         different service might still synchronize the clock with the
 116         network.</para></listitem>
 117       </varlistentry>
 118
 119       <varlistentry>
 120         <term><command>set-time [TIME]</command></term>
 121
 122         <listitem><para>Set the system clock to the specified time.
 123         This will also update the RTC time accordingly. The time may
 124         be specified in the format "2012-10-30
 125         18:17:16".</para></listitem>
 126       </varlistentry>
 127
 128       <varlistentry>
 129         <term><command>set-timezone [TIMEZONE]</command></term>
 130
 131         <listitem><para>Set the system time zone to the specified
 132         value. Available timezones can be listed with
 133         <command>list-timezones</command>. If the RTC is configured to
 134         be in the local time, this will also update the RTC time. This
 135         call will alter the <filename>/etc/localtime</filename>
 136         symlink. See
 137         <citerefentry><refentrytitle>localtime</refentrytitle><manvolnum>5</manvolnum></citerefentry>
 138         for more information.</para></listitem>
 139       </varlistentry>
 140
 141       <varlistentry>
 142         <term><command>list-timezones</command></term>
 143
 144         <listitem><para>List available time zones, one per line.
 145         Entries from the list can be set as the system timezone with
 146         <command>set-timezone</command>.</para></listitem>
 147       </varlistentry>
 148
 149       <varlistentry>
 150         <term><command>set-local-rtc [BOOL]</command></term>
 151
 152         <listitem><para>Takes a boolean argument. If
 153         <literal>0</literal>, the system is configured to maintain the
 154         RTC in universal time. If <literal>1</literal>, it will
 155         maintain the RTC in local time instead. Note that maintaining
 156         the RTC in the local timezone is not fully supported and will
 157         create various problems with time zone changes and daylight
 158         saving adjustments. If at all possible, keep the RTC in UTC
 159         mode. Note that invoking this will also synchronize the RTC
 160         from the system clock, unless
 161         <option>--adjust-system-clock</option> is passed (see above).
 162         This command will change the 3rd line of
 163         <filename>/etc/adjtime</filename>, as documented in
 164         <citerefentry project='man-pages'><refentrytitle>hwclock</refentrytitle><manvolnum>8</manvolnum></citerefentry>.
 165         </para></listitem>
 166       </varlistentry>
 167
 168       <varlistentry>
 169         <term><command>set-ntp [BOOL]</command></term>
 170
 171         <listitem><para>Takes a boolean argument. Controls whether
 172         network time synchronization is enabled (if available). This
 173         enables or disables the
 174         <filename>systemd-timesyncd.service</filename> unit. Note that
 175         even if this command turns time synchronization off a
 176         different system service might still synchronize the clock
 177         with the network.</para></listitem>
 178       </varlistentry>
 179
 180     </variablelist>
 181
 182   </refsect1>
 183
 184   <refsect1>
 185     <title>Exit status</title>
 186
 187     <para>On success, 0 is returned, a non-zero failure
 188     code otherwise.</para>
 189   </refsect1>
 190
 191   <xi:include href="less-variables.xml" />
 192
 193   <refsect1>
 194     <title>Examples</title>
 195     <para>Show current settings:
 196     <programlisting>$ timedatectl
 197       Local time: Di 2015-04-07 16:26:56 CEST
 198   Universal time: Di 2015-04-07 14:26:56 UTC
 199         RTC time: Di 2015-04-07 14:26:56
 200        Time zone: Europe/Berlin (CEST, +0200)
 201  Network time on: yes
 202 NTP synchronized: yes
 203  RTC in local TZ: no</programlisting>
 204     </para>
 205
 206     <para>Enable network time synchronization:
 207     <programlisting>$ timedatectl set-ntp true
 208 ==== AUTHENTICATING FOR org.freedesktop.timedate1.set-ntp ===
 209 Authentication is required to control whether network time synchronization shall be enabled.
 210 Authenticating as: user
 211 Password: ********
 212 ==== AUTHENTICATION COMPLETE ===</programlisting>
 213
 214     <programlisting>$ systemctl status systemd-timesyncd.service
 215 ● systemd-timesyncd.service - Network Time Synchronization
 216    Loaded: loaded (&rootlibexecdir;/system/systemd-timesyncd.service; enabled)
 217    Active: active (running) since Mo 2015-03-30 14:20:38 CEST; 5s ago
 218      Docs: man:systemd-timesyncd.service(8)
 219  Main PID: 595 (systemd-timesyn)
 220    Status: "Using Time Server 216.239.38.15:123 (time4.google.com)."
 221    CGroup: /system.slice/systemd-timesyncd.service
 222            └─595 &rootlibexecdir;/systemd-timesyncd
 223 ...</programlisting>
 224     </para>
 225   </refsect1>
 226
 227   <refsect1>
 228     <title>See Also</title>
 229     <para>
 230       <citerefentry><refentrytitle>systemd</refentrytitle><manvolnum>1</manvolnum></citerefentry>,
 231       <citerefentry project='man-pages'><refentrytitle>hwclock</refentrytitle><manvolnum>8</manvolnum></citerefentry>,
 232       <citerefentry project='man-pages'><refentrytitle>date</refentrytitle><manvolnum>1</manvolnum></citerefentry>,
 233       <citerefentry><refentrytitle>localtime</refentrytitle><manvolnum>5</manvolnum></citerefentry>,
 234       <citerefentry><refentrytitle>systemctl</refentrytitle><manvolnum>1</manvolnum></citerefentry>,
 235       <citerefentry><refentrytitle>systemd-timedated.service</refentrytitle><manvolnum>8</manvolnum></citerefentry>,
 236       <citerefentry><refentrytitle>systemd-timesyncd.service</refentrytitle><manvolnum>8</manvolnum></citerefentry>,
 237       <citerefentry><refentrytitle>systemd-firstboot</refentrytitle><manvolnum>1</manvolnum></citerefentry>
 238     </para>
 239   </refsect1>
 240
 241 </refentry>