diff options
Diffstat (limited to 'man/systemd-machine-id-setup.xml')
| -rw-r--r-- | man/systemd-machine-id-setup.xml | 100 |
1 files changed, 74 insertions, 26 deletions
diff --git a/man/systemd-machine-id-setup.xml b/man/systemd-machine-id-setup.xml index 182717f524..efcf408332 100644 --- a/man/systemd-machine-id-setup.xml +++ b/man/systemd-machine-id-setup.xml @@ -1,4 +1,4 @@ -<?xml version='1.0'?> <!--*-nxml-*--> +<?xml version='1.0'?> <!--*- Mode: nxml; nxml-child-indent: 2; indent-tabs-mode: nil -*--> <!DOCTYPE refentry PUBLIC "-//OASIS//DTD DocBook XML V4.2//EN" "http://www.oasis-open.org/docbook/xml/4.2/docbookx.dtd"> @@ -35,6 +35,12 @@ <surname>Poettering</surname> <email>lennart@poettering.net</email> </author> + <author> + <contrib>Developer</contrib> + <firstname>Didier</firstname> + <surname>Roche</surname> + <email>didrocks@ubuntu.com</email> + </author> </authorgroup> </refentryinfo> @@ -59,30 +65,43 @@ <para><command>systemd-machine-id-setup</command> may be used by system installer tools to initialize the machine ID stored in - <filename>/etc/machine-id</filename> at install time with a - randomly generated ID. See + <filename>/etc/machine-id</filename> at install time, with a + provisioned or randomly generated ID. See <citerefentry><refentrytitle>machine-id</refentrytitle><manvolnum>5</manvolnum></citerefentry> for more information about this file.</para> - <para>This tool will execute no operation if - <filename>/etc/machine-id</filename> is already - initialized.</para> - - <para>If a valid D-Bus machine ID is already configured for the - system, the D-Bus machine ID is copied and used to initialize the - machine ID in <filename>/etc/machine-id</filename>.</para> - - <para>If run inside a KVM virtual machine and a UUID is passed via - the <option>-uuid</option> option, this UUID is used to initialize - the machine ID instead of a randomly generated one. The caller - must ensure that the UUID passed is sufficiently unique and is - different for every booted instanced of the VM.</para> - - <para>Similar, if run inside a Linux container environment and a - UUID is set for the container this is used to initialize the - machine ID. For details see the documentation of the <ulink - url="http://www.freedesktop.org/wiki/Software/systemd/ContainerInterface">Container - Interface</ulink>.</para> + <para>If the tool is invoked without the <option>--commit</option> + switch <filename>/etc/machine-id</filename> is initialized with a + valid, new machined ID if it is missing or empty. The new machine + ID will be acquired in the following fashion:</para> + + <orderedlist> + <listitem><para>If a valid D-Bus machine ID is already + configured for the system, the D-Bus machine ID is copied and + used to initialize the machine ID in + <filename>/etc/machine-id</filename>.</para></listitem> + + <listitem><para>If run inside a KVM virtual machine and a UUID + is was configured (via the <option>-uuid</option> + option), this UUID is used to initialize the machine ID. The + caller must ensure that the UUID passed is sufficiently unique + and is different for every booted instance of the + VM.</para></listitem> + + <listitem><para>Similar, if run inside a Linux container + environment and a UUID is configured for the container this is + used to initialize the machine ID. For details see the + documentation of the <ulink + url="http://www.freedesktop.org/wiki/Software/systemd/ContainerInterface">Container + Interface</ulink>.</para></listitem> + + <listitem><para>Otherwise a new ID is randomly + generated.</para></listitem> + </orderedlist> + + <para>The <option>--commit</option> switch may be used to commit a + transient machined ID to disk, making it persistent. For details, + see below.</para> <para>Use <citerefentry><refentrytitle>systemd-firstboot</refentrytitle><manvolnum>1</manvolnum></citerefentry> @@ -97,13 +116,41 @@ <para>The following options are understood:</para> <variablelist> + <varlistentry> <term><option>--root=<replaceable>root</replaceable></option></term> - <listitem><para>Takes a directory path as an argument. All - paths will be prefixed with the given alternate - <replaceable>root</replaceable> path, including config search - paths. </para></listitem> + <listitem><para>Takes a directory path as argument. All paths + operated will be prefixed with the given alternate + <replaceable>root</replaceable> path, including the path for + <filename>/etc/machine-id</filename> itself.</para></listitem> </varlistentry> + + <varlistentry> + <term><option>--commit</option></term> + <listitem><para>Commit a transient machine ID to disk. This + command may be used to convert a transient machine ID into a + persistent one. A transient machine ID file is one that was + bind mounted from a memory file system (usually + <literal>tmpfs</literal>) to + <filename>/etc/machine-id</filename> during the early phase of + the boot process. This may happen because + <filename>/etc</filename> is initially read-only and was + missing a valid machine ID file at that point.</para> + + <para>This command will execute no operation if + <filename>/etc/machine-id</filename> is not mounted from a + memory file system, or if <filename>/etc</filename> is + read-only. The command will write the current transient + machine ID to disk and unmount the + <filename>/etc/machine-id</filename> mount point in a + race-free manner to ensure that this file is always valid and + accessible for other processes.</para> + + <para>This command is primarily used by the + <citerefentry><refentrytitle>systemd-machine-id-commit.service</refentrytitle><manvolnum>8</manvolnum></citerefentry> + early-boot service.</para></listitem> + </varlistentry> + <xi:include href="standard-options.xml" xpointer="help" /> <xi:include href="standard-options.xml" xpointer="version" /> </variablelist> @@ -122,6 +169,7 @@ <para> <citerefentry><refentrytitle>systemd</refentrytitle><manvolnum>1</manvolnum></citerefentry>, <citerefentry><refentrytitle>machine-id</refentrytitle><manvolnum>5</manvolnum></citerefentry>, + <citerefentry><refentrytitle>systemd-machine-id-commit.service</refentrytitle><manvolnum>8</manvolnum></citerefentry>, <citerefentry project='dbus'><refentrytitle>dbus-uuidgen</refentrytitle><manvolnum>1</manvolnum></citerefentry>, <citerefentry><refentrytitle>systemd-firstboot</refentrytitle><manvolnum>1</manvolnum></citerefentry> </para> |