man/systemd-time-wait-sync.service.xml

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   2 <!DOCTYPE refentry PUBLIC "-//OASIS//DTD DocBook XML V4.2//EN"
   3   "http://www.oasis-open.org/docbook/xml/4.2/docbookx.dtd">
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   5 <!--
   6   SPDX-License-Identifier: LGPL-2.1+
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   8
   9 <refentry id="systemd-time-wait-sync.service" conditional='ENABLE_TIMESYNCD'>
  10
  11   <refentryinfo>
  12     <title>systemd-time-wait-sync.service</title>
  13     <productname>systemd</productname>
  14   </refentryinfo>
  15
  16   <refmeta>
  17     <refentrytitle>systemd-time-wait-sync.service</refentrytitle>
  18     <manvolnum>8</manvolnum>
  19   </refmeta>
  20
  21   <refnamediv>
  22     <refname>systemd-time-wait-sync.service</refname>
  23     <refname>systemd-time-wait-sync</refname>
  24     <refpurpose>Wait Until Kernel Time Synchronized</refpurpose>
  25   </refnamediv>
  26
  27   <refsynopsisdiv>
  28     <para><filename>systemd-time-wait-sync.service</filename></para>
  29     <para><filename>/usr/lib/systemd/systemd-time-wait-sync</filename></para>
  30   </refsynopsisdiv>
  31
  32   <refsect1>
  33     <title>Description</title>
  34
  35     <para><filename>systemd-time-wait-sync</filename> is a system service that delays the start of units that depend on
  36     <filename>time-sync.target</filename> until the system time has been synchronized with an accurate time source by
  37     <filename>systemd-timesyncd.service</filename>.</para>
  38
  39     <para><filename>systemd-timesyncd.service</filename> notifies on successful synchronization.
  40     <filename>systemd-time-wait-sync</filename> also tries to detect when the kernel marks the time as synchronized,
  41     but this detection is not reliable and is intended only as a fallback for other servies that can be used to
  42     synchronize time (e.g., ntpd, chronyd).</para>
  43
  44   </refsect1>
  45
  46   <refsect1>
  47     <title>Files</title>
  48
  49     <variablelist>
  50       <varlistentry>
  51         <term><filename>/run/systemd/timesync/synchronized</filename></term>
  52
  53         <listitem>
  54           <para>The presence of this file indicates to this service that the system clock has been synchronized.</para>
  55         </listitem>
  56
  57       </varlistentry>
  58     </variablelist>
  59
  60   </refsect1>
  61
  62   <refsect1>
  63     <title>See Also</title>
  64     <para>
  65       <citerefentry><refentrytitle>systemd</refentrytitle><manvolnum>1</manvolnum></citerefentry>,
  66       <citerefentry><refentrytitle>systemd.special</refentrytitle><manvolnum>7</manvolnum></citerefentry>,
  67       <citerefentry><refentrytitle>systemd-timesyncd.service</refentrytitle><manvolnum>8</manvolnum></citerefentry>,
  68     </para>
  69   </refsect1>
  70
  71 </refentry>