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login: simplify controller handling
[elogind.git] / man / systemd-timesyncd.service.xml
1 <?xml version='1.0'?> <!--*-nxml-*-->
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 <!--
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8   Copyright 2014 Kay Sievers
9
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22 -->
23
24 <refentry id="systemd-timesyncd.service" conditional='ENABLE_TIMESYNCD'>
25
26         <refentryinfo>
27                 <title>systemd-timesyncd.service</title>
28                 <productname>systemd</productname>
29
30                 <authorgroup>
31                         <author>
32                                 <contrib>Developer</contrib>
33                                 <firstname>Kay</firstname>
34                                 <surname>Sievers</surname>
35                                 <email>kay@vrfy.org</email>
36                         </author>
37                 </authorgroup>
38         </refentryinfo>
39
40         <refmeta>
41                 <refentrytitle>systemd-timesyncd.service</refentrytitle>
42                 <manvolnum>8</manvolnum>
43         </refmeta>
44
45         <refnamediv>
46                 <refname>systemd-timesyncd.service</refname>
47                 <refname>systemd-timesyncd</refname>
48                 <refpurpose>Network Time Synchronization</refpurpose>
49         </refnamediv>
50
51         <refsynopsisdiv>
52                 <para><filename>systemd-timesyncd.service</filename></para>
53                 <para><filename>/usr/lib/systemd/systemd-timesyncd</filename></para>
54         </refsynopsisdiv>
55
56         <refsect1>
57                 <title>Description</title>
58
59                 <para><filename>systemd-timesyncd</filename> is a
60                 system service that may be used to synchronize the
61                 local system clock with a remote Network Time Protocol
62                 server. It also saves the local time to disk every
63                 time the clock has been synchronized and uses this to
64                 possibly advance the system realtime clock on
65                 subsequent reboots to ensure it
66                 monotonically advances even if the system lacks a
67                 battery-buffered RTC chip.</para>
68
69                 <para>The NTP servers contacted are determined from
70                 the global settings in
71                 <citerefentry><refentrytitle>timesyncd.conf</refentrytitle><manvolnum>5</manvolnum></citerefentry>,
72                 the per-link static settings in
73                 <filename>.network</filename> files, and the per-link
74                 dynamic settings received over DHCP. See
75                 <citerefentry><refentrytitle>systemd.network</refentrytitle><manvolnum>5</manvolnum></citerefentry>
76                 for more details.</para>
77         </refsect1>
78
79         <refsect1>
80                 <title>See Also</title>
81                 <para>
82                         <citerefentry><refentrytitle>systemd</refentrytitle><manvolnum>1</manvolnum></citerefentry>,
83                         <citerefentry><refentrytitle>timesyncd.conf</refentrytitle><manvolnum>5</manvolnum></citerefentry>,
84                         <citerefentry><refentrytitle>systemd.network</refentrytitle><manvolnum>5</manvolnum></citerefentry>,
85                         <citerefentry><refentrytitle>systemd-networkd.service</refentrytitle><manvolnum>8</manvolnum></citerefentry>,
86                         <citerefentry><refentrytitle>timedatectl</refentrytitle><manvolnum>1</manvolnum></citerefentry>,
87                         <citerefentry><refentrytitle>localtime</refentrytitle><manvolnum>5</manvolnum></citerefentry>,
88                         <citerefentry project='man-pages'><refentrytitle>hwclock</refentrytitle><manvolnum>8</manvolnum></citerefentry>
89                 </para>
90         </refsect1>
91
92 </refentry>