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Diffstat (limited to 'man/machine-id.xml')
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diff --git a/man/machine-id.xml b/man/machine-id.xml deleted file mode 100644 index 7d424b705b..0000000000 --- a/man/machine-id.xml +++ /dev/null @@ -1,145 +0,0 @@ -<?xml version='1.0'?> <!--*-nxml-*--> -<?xml-stylesheet type="text/xsl" href="http://docbook.sourceforge.net/release/xsl/current/xhtml/docbook.xsl"?> -<!DOCTYPE refentry PUBLIC "-//OASIS//DTD DocBook XML V4.2//EN" - "http://www.oasis-open.org/docbook/xml/4.2/docbookx.dtd"> - -<!-- - This file is part of systemd. - - Copyright 2010 Lennart Poettering - - systemd is free software; you can redistribute it and/or modify it - under the terms of the GNU Lesser General Public License as published by - the Free Software Foundation; either version 2.1 of the License, or - (at your option) any later version. - - systemd is distributed in the hope that it will be useful, but - WITHOUT ANY WARRANTY; without even the implied warranty of - MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU - Lesser General Public License for more details. - - You should have received a copy of the GNU Lesser General Public License - along with systemd; If not, see <http://www.gnu.org/licenses/>. ---> - -<refentry id="machine-id"> - <refentryinfo> - <title>/etc/machine-id</title> - <productname>systemd</productname> - - <authorgroup> - <author> - <contrib>Developer</contrib> - <firstname>Lennart</firstname> - <surname>Poettering</surname> - <email>lennart@poettering.net</email> - </author> - </authorgroup> - </refentryinfo> - - <refmeta> - <refentrytitle>machine-id</refentrytitle> - <manvolnum>5</manvolnum> - </refmeta> - - <refnamediv> - <refname>machine-id</refname> - <refpurpose>Local machine ID configuration file</refpurpose> - </refnamediv> - - <refsynopsisdiv> - <para><filename>/etc/machine-id</filename></para> - </refsynopsisdiv> - - <refsect1> - <title>Description</title> - - <para>The <filename>/etc/machine-id</filename> file - contains the unique machine id of the local system - that is set during installation. The machine ID is a - single newline-terminated, hexadecimal, lowercase 32 - character machine ID string. (When decoded from - hexadecimal this corresponds with a 16 byte/128 bit - string.)</para> - - <para>The machine ID is usually generated from a - random source during system installation and stays - constant for all subsequent boots. Optionally, for - stateless systems it is generated during runtime at - boot if it is found to be empty.</para> - - <para>The machine ID does not change based on user - configuration, or when hardware is replaced.</para> - - <para>This machine ID adheres to the same format and - logic as the D-Bus machine ID.</para> - - <para>Programs may use this ID to identify the host - with a globally unique ID in the network, that does - not change even if the local network configuration - changes. Due to this and its greater length it is - a more useful replacement for the - <citerefentry><refentrytitle>gethostid</refentrytitle><manvolnum>3</manvolnum></citerefentry> - call POSIX specifies.</para> - - <para>The - <citerefentry><refentrytitle>systemd-machine-id-setup</refentrytitle><manvolnum>1</manvolnum></citerefentry> - tool may be used by installer tools to initialize the - machine ID at install time.</para> - </refsect1> - - <refsect1> - <title>Relation to OSF UUIDs</title> - - <para>Note that the machine ID historically is not an - OSF UUID as defined by <ulink - url="http://tools.ietf.org/html/rfc4122">RFC - 4122</ulink>, nor a Microsoft GUID. Starting with - systemd v30 newly generated machine IDs however do - qualify as v4 UUIDs.</para> - - <para>In order to maintain compatibility with existing - installations, an application requiring a UUID should - decode the machine ID, and then apply the following - operations to turn it into a valid OSF v4 UUID. With - <literal>id</literal> being an unsigned character - array:</para> - - <programlisting>/* Set UUID version to 4 --- truly random generation */ -id[6] = (id[6] & 0x0F) | 0x40; -/* Set the UUID variant to DCE */ -id[8] = (id[8] & 0x3F) | 0x80;</programlisting> - - <para>(This code is inspired by - <literal>generate_random_uuid()</literal> of - <filename>drivers/char/random.c</filename> from the - kernel sources.)</para> - - </refsect1> - - <refsect1> - <title>History</title> - - <para>The simple configuration file format of - <filename>/etc/machine-id</filename> originates in the - <filename>/var/lib/dbus/machine-id</filename> file - introduced by D-Bus. In fact this latter file might be a - symlink to - <varname>/etc/machine-id</varname>.</para> - </refsect1> - - <refsect1> - <title>See Also</title> - <para> - <citerefentry><refentrytitle>systemd</refentrytitle><manvolnum>1</manvolnum></citerefentry>, - <citerefentry><refentrytitle>systemd-machine-id-setup</refentrytitle><manvolnum>1</manvolnum></citerefentry>, - <citerefentry><refentrytitle>gethostid</refentrytitle><manvolnum>3</manvolnum></citerefentry>, - <citerefentry><refentrytitle>hostname</refentrytitle><manvolnum>5</manvolnum></citerefentry>, - <citerefentry><refentrytitle>machine-info</refentrytitle><manvolnum>5</manvolnum></citerefentry>, - <citerefentry><refentrytitle>os-release</refentrytitle><manvolnum>5</manvolnum></citerefentry>, - <citerefentry><refentrytitle>sd-id128</refentrytitle><manvolnum>3</manvolnum></citerefentry>, - <citerefentry><refentrytitle>sd_id128_get_machine</refentrytitle><manvolnum>3</manvolnum></citerefentry> - </para> - </refsect1> - -</refentry> |