mirror of
https://github.com/systemd/systemd.git
synced 2024-12-04 15:53:41 +08:00
75 lines
3.0 KiB
XML
75 lines
3.0 KiB
XML
<?xml version="1.0"?>
|
|
<!--*-nxml-*-->
|
|
<!DOCTYPE refentry PUBLIC "-//OASIS//DTD DocBook XML V4.5//EN"
|
|
"http://www.oasis-open.org/docbook/xml/4.5/docbookx.dtd">
|
|
<!--
|
|
SPDX-License-Identifier: LGPL-2.1-or-later
|
|
|
|
Copyright © 2014 Didier Roche
|
|
-->
|
|
<refentry id="systemd-machine-id-commit.service">
|
|
|
|
<refentryinfo>
|
|
<title>systemd-machine-id-commit.service</title>
|
|
<productname>systemd</productname>
|
|
</refentryinfo>
|
|
|
|
<refmeta>
|
|
<refentrytitle>systemd-machine-id-commit.service</refentrytitle>
|
|
<manvolnum>8</manvolnum>
|
|
</refmeta>
|
|
|
|
<refnamediv>
|
|
<refname>systemd-machine-id-commit.service</refname>
|
|
<refpurpose>Commit a transient machine ID to disk</refpurpose>
|
|
</refnamediv>
|
|
|
|
<refsynopsisdiv>
|
|
<para><filename>systemd-machine-id-commit.service</filename></para>
|
|
</refsynopsisdiv>
|
|
|
|
<refsect1>
|
|
<title>Description</title>
|
|
|
|
<para><filename>systemd-machine-id-commit.service</filename> is an
|
|
early boot service responsible for committing transient
|
|
<filename>/etc/machine-id</filename> files to a writable disk file
|
|
system. See
|
|
<citerefentry><refentrytitle>machine-id</refentrytitle><manvolnum>5</manvolnum></citerefentry>
|
|
for more information about machine IDs.</para>
|
|
|
|
<para>This service is started after
|
|
<filename>local-fs.target</filename> in case
|
|
<filename>/etc/machine-id</filename> is a mount point of its own
|
|
(usually from a memory file system such as
|
|
<literal>tmpfs</literal>) and /etc is writable. The service will
|
|
invoke <command>systemd-machine-id-setup --commit</command>, which
|
|
writes the current transient machine ID to disk and unmount the
|
|
<filename>/etc/machine-id</filename> file in a race-free manner to
|
|
ensure that file is always valid and accessible for other
|
|
processes. See
|
|
<citerefentry><refentrytitle>systemd-machine-id-setup</refentrytitle><manvolnum>1</manvolnum></citerefentry>
|
|
for details.</para>
|
|
|
|
<para>The main use case of this service are systems where
|
|
<filename>/etc/machine-id</filename> is read-only and initially
|
|
not initialized. In this case, the system manager will generate a
|
|
transient machine ID file on a memory file system, and mount it
|
|
over <filename>/etc/machine-id</filename>, during the early boot
|
|
phase. This service is then invoked in a later boot phase, as soon
|
|
as <filename>/etc/</filename> has been remounted writable and the
|
|
ID may thus be committed to disk to make it permanent.</para>
|
|
</refsect1>
|
|
|
|
<refsect1>
|
|
<title>See Also</title>
|
|
<para><simplelist type="inline">
|
|
<member><citerefentry><refentrytitle>systemd</refentrytitle><manvolnum>1</manvolnum></citerefentry></member>
|
|
<member><citerefentry><refentrytitle>systemd-machine-id-setup</refentrytitle><manvolnum>1</manvolnum></citerefentry></member>
|
|
<member><citerefentry><refentrytitle>machine-id</refentrytitle><manvolnum>5</manvolnum></citerefentry></member>
|
|
<member><citerefentry><refentrytitle>systemd-firstboot</refentrytitle><manvolnum>1</manvolnum></citerefentry></member>
|
|
</simplelist></para>
|
|
</refsect1>
|
|
|
|
</refentry>
|