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+ SPDX-License-Identifier: LGPL-2.1+
+
This file is part of systemd.
Copyright 2012 Lennart Poettering
<varlistentry>
<term><command>status</command></term>
- <listitem><para>Show current settings of the system clock and
- RTC, including whether network time synchronization is
- on. Note that whether network time synchronization is on
- simply reflects whether the
- <filename>systemd-timesyncd.service</filename> unit is
- enabled. Even if this command shows the status as off a
- different service might still synchronize the clock with the
- network.</para></listitem>
+ <listitem><para>Show current settings of the system clock and RTC,
+ including whether network time synchronization through
+ <filename>systemd-timesyncd.service</filename> is active. Even if it is
+ inactive, a different service might still synchronize the clock.
+ </para></listitem>
</varlistentry>
<varlistentry>
<term><command>set-ntp [BOOL]</command></term>
<listitem><para>Takes a boolean argument. Controls whether
- network time synchronization is enabled (if available). This
- enables or disables the
- <filename>systemd-timesyncd.service</filename> unit. Note that
- even if this command turns time synchronization off a
- different system service might still synchronize the clock
- with the network.</para></listitem>
+ network time synchronization is active and enabled (if
+ available). This enables and starts, or disables and stops the
+ <filename>systemd-timesyncd.service</filename> unit. It does
+ not affect the state of any other, unrelated network time
+ synchronization services that might be installed on the
+ system. This command is hence mostly equivalent to:
+ <command>systemctl enable --now
+ systemd-timesyncd.service</command> and <command>systemctl
+ disable --now systemd-timesyncd.service</command>, but is
+ protected by a different access policy.</para>
+
+ <para>Note that even if time synchronization is turned off
+ with this command, another unrelated system service might
+ still synchronize the clock with the network. Also note that,
+ strictly speaking,
+ <filename>systemd-timesyncd.service</filename> does more than
+ just network time synchronization, as it ensures a monotonic
+ clock on systems without RTC even if no network is
+ available. See
+ <citerefentry><refentrytitle>systemd-timesyncd.service</refentrytitle><manvolnum>8</manvolnum></citerefentry>
+ for details about this.</para></listitem>
</varlistentry>
</variablelist>
<title>Examples</title>
<para>Show current settings:
<programlisting>$ timedatectl
- Local time: Di 2015-04-07 16:26:56 CEST
- Universal time: Di 2015-04-07 14:26:56 UTC
- RTC time: Di 2015-04-07 14:26:56
- Time zone: Europe/Berlin (CEST, +0200)
- Network time on: yes
-NTP synchronized: yes
- RTC in local TZ: no</programlisting>
+ Local time: Thu 2017-09-21 16:08:56 CEST
+ Universal time: Thu 2017-09-21 14:08:56 UTC
+ RTC time: Thu 2017-09-21 14:08:56
+ Time zone: Europe/Warsaw (CEST, +0200)
+ System clock synchronized: yes
+systemd-timesyncd.service active: yes
+ RTC in local TZ: no</programlisting>
</para>
<para>Enable network time synchronization:
<programlisting>$ systemctl status systemd-timesyncd.service
● systemd-timesyncd.service - Network Time Synchronization
- Loaded: loaded (&rootlibexecdir;/system/systemd-timesyncd.service; enabled)
+ Loaded: loaded (/usr/lib/systemd/system/systemd-timesyncd.service; enabled)
Active: active (running) since Mo 2015-03-30 14:20:38 CEST; 5s ago
Docs: man:systemd-timesyncd.service(8)
Main PID: 595 (systemd-timesyn)
Status: "Using Time Server 216.239.38.15:123 (time4.google.com)."
CGroup: /system.slice/systemd-timesyncd.service
- └─595 &rootlibexecdir;/systemd-timesyncd
-...</programlisting>
+ └─595 /usr/lib/systemd/systemd-timesyncd
+…</programlisting>
</para>
</refsect1>