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">
   4
   5 <!--
   6   SPDX-License-Identifier: LGPL-2.1+
   7
   8   Copyright © 2018 Peter A. Bigot
   9 -->
  10
  11 <refentry id="systemd-time-wait-sync.service" conditional='ENABLE_TIMESYNCD'>
  12
  13   <refentryinfo>
  14     <title>systemd-time-wait-sync.service</title>
  15     <productname>systemd</productname>
  16
  17     <authorgroup>
  18       <author>
  19         <contrib>Developer</contrib>
  20         <firstname>Peter</firstname>
  21         <surname>Bigot</surname>
  22         <email>pab@pabigot.com</email>
  23       </author>
  24     </authorgroup>
  25   </refentryinfo>
  26
  27   <refmeta>
  28     <refentrytitle>systemd-time-wait-sync.service</refentrytitle>
  29     <manvolnum>8</manvolnum>
  30   </refmeta>
  31
  32   <refnamediv>
  33     <refname>systemd-time-wait-sync.service</refname>
  34     <refname>systemd-time-wait-sync</refname>
  35     <refpurpose>Wait Until Kernel Time Synchronized</refpurpose>
  36   </refnamediv>
  37
  38   <refsynopsisdiv>
  39     <para><filename>systemd-time-wait-sync.service</filename></para>
  40     <para><filename>/usr/lib/systemd/systemd-time-wait-sync</filename></para>
  41   </refsynopsisdiv>
  42
  43   <refsect1>
  44     <title>Description</title>
  45
  46     <para><filename>systemd-time-wait-sync</filename> is a system service that delays the start of units that depend on
  47     <filename>time-sync.target</filename> until the system time has been synchronized with an accurate time source by
  48     <filename>systemd-timesyncd.service</filename>.</para>
  49
  50     <para><filename>systemd-timesyncd.service</filename> notifies on successful synchronization.
  51     <filename>systemd-time-wait-sync</filename> also tries to detect when the kernel marks the time as synchronized,
  52     but this detection is not reliable and is intended only as a fallback for other servies that can be used to
  53     synchronize time (e.g., ntpd, chronyd).</para>
  54
  55   </refsect1>
  56
  57   <refsect1>
  58     <title>Files</title>
  59
  60     <variablelist>
  61       <varlistentry>
  62         <term><filename>/run/systemd/timesync/synchronized</filename></term>
  63
  64         <listitem>
  65           <para>The presence of this file indicates to this service that the system clock has been synchronized.</para>
  66         </listitem>
  67
  68       </varlistentry>
  69     </variablelist>
  70
  71   </refsect1>
  72
  73   <refsect1>
  74     <title>See Also</title>
  75     <para>
  76       <citerefentry><refentrytitle>systemd</refentrytitle><manvolnum>1</manvolnum></citerefentry>,
  77       <citerefentry><refentrytitle>systemd.special</refentrytitle><manvolnum>7</manvolnum></citerefentry>,
  78       <citerefentry><refentrytitle>systemd-timesyncd.service</refentrytitle><manvolnum>8</manvolnum></citerefentry>,
  79     </para>
  80   </refsect1>
  81
  82 </refentry>