-<?xml version="1.0"?> <!--*- Mode: nxml; nxml-child-indent: 2; indent-tabs-mode: nil -*-->
+<?xml version="1.0"?>
<!DOCTYPE refsection 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+
+ Copyright © 2014 Josh Triplett
+-->
+
<refsection>
<refsection id='confd'>
<title>Configuration Directories and Precedence</title>
- <para>Configuration files are read from directories in
- <filename>/etc/</filename>, <filename>/run/</filename>, and
- <filename>/usr/lib/</filename>, in order of precedence.
- Each configuration file in these configuration directories shall be named in
- the style of <filename><replaceable>filename</replaceable>.conf</filename>.
- Files in <filename>/etc/</filename> override files with the same name in
- <filename>/run/</filename> and <filename>/usr/lib/</filename>. Files in
- <filename>/run/</filename> override files with the same name in
- <filename>/usr/lib/</filename>.</para>
+ <para>Configuration files are read from directories in <filename>/etc/</filename>,
+ <filename>/run/</filename>, <filename>/usr/local/lib/</filename>, and <filename>/usr/lib/</filename>, in
+ order of precedence, as listed in the SYNOPSIS section above. Files must have the
+ <literal>.conf</literal> extension. Files in <filename>/etc/</filename> override files with the same name
+ in <filename>/run/</filename>, <filename>/usr/local/lib/</filename>, and
+ <filename>/usr/lib/</filename>. Files in <filename>/run/</filename> override files with the same name
+ under <filename>/usr/</filename>.</para>
- <para>Packages should install their configuration files in
- <filename>/usr/lib/</filename>. Files in <filename>/etc/</filename> are
- reserved for the local administrator, who may use this logic to override the
- configuration files installed by vendor packages. All configuration files
- are sorted by their filename in lexicographic order, regardless of which of
- the directories they reside in. If multiple files specify the same option,
- the entry in the file with the lexicographically latest name will take
- precedence. It is recommended to prefix all filenames with a two-digit number
- and a dash, to simplify the ordering of the files.</para>
+ <para>All configuration files are sorted by their filename in lexicographic order, regardless of which of
+ the directories they reside in. If multiple files specify the same option, the entry in the file with the
+ lexicographically latest name will take precedence. Thus, the configuration in a certain file may either
+ be replaced completely (by placing a file with the same name in a directory with higher priority), or
+ individual settings might be changed (by specifying additional settings in a file with a different name
+ that is ordered later).</para>
- <para>If the administrator wants to disable a configuration file supplied by
- the vendor, the recommended way is to place a symlink to
- <filename>/dev/null</filename> in the configuration directory in
- <filename>/etc/</filename>, with the same filename as the vendor
- configuration file. If the vendor configuration file is included in
- the initrd image, the image has to be regenerated.</para>
+ <para>Packages should install their configuration files in <filename>/usr/lib/</filename> (distribution
+ packages) or <filename>/usr/local/lib/</filename> (local installs). Files in <filename>/etc/</filename>
+ are reserved for the local administrator, who may use this logic to override the configuration files
+ installed by vendor packages. It is recommended to prefix all filenames with a two-digit number and a
+ dash, to simplify the ordering of the files.</para>
+ <para>If the administrator wants to disable a configuration file supplied by the vendor, the recommended
+ way is to place a symlink to <filename>/dev/null</filename> in the configuration directory in
+ <filename>/etc/</filename>, with the same filename as the vendor configuration file. If the vendor
+ configuration file is included in the initrd image, the image has to be regenerated.</para>
</refsection>
<refsection id='main-conf'>
can be edited to create local overrides.
</para>
- <para>When packages need to customize the configuration, they can
- install configuration snippets in
- <filename>/usr/lib/systemd/*.conf.d/</filename>. Files in
- <filename>/etc/</filename> are reserved for the local
- administrator, who may use this logic to override the
- configuration files installed by vendor packages. The main
- configuration file is read before any of the configuration
- directories, and has the lowest precedence; entries in a file in
- any configuration directory override entries in the single
- configuration file. Files in the
- <filename>*.conf.d/</filename> configuration subdirectories
- are sorted by their filename in lexicographic order, regardless of
- which of the subdirectories they reside in. If multiple files
- specify the same option, the entry in the file with the
- lexicographically latest name takes precedence. It is recommended
- to prefix all filenames in those subdirectories with a two-digit
- number and a dash, to simplify the ordering of the files.</para>
+ <para>When packages need to customize the configuration, they can install configuration snippets in
+ <filename>/usr/lib/systemd/*.conf.d/</filename> or <filename>/usr/local/lib/systemd/*.conf.d/</filename>.
+ The main configuration file is read before any of the configuration directories, and has the lowest
+ precedence; entries in a file in any configuration directory override entries in the single configuration
+ file. Files in the <filename>*.conf.d/</filename> configuration subdirectories are sorted by their
+ filename in lexicographic order, regardless of in which of the subdirectories they reside. When multiple
+ files specify the same option, for options which accept just a single value, the entry in the file with
+ the lexicographically latest name takes precedence. For options which accept a list of values, entries
+ are collected as they occur in files sorted lexicographically.</para>
+
+ <para>Files in <filename>/etc/</filename> are reserved for the local administrator, who may use this
+ logic to override the configuration files installed by vendor packages. It is recommended to prefix all
+ filenames in those subdirectories with a two-digit number and a dash, to simplify the ordering of the
+ files.</para>
<para>To disable a configuration file supplied by the vendor, the
recommended way is to place a symlink to
projects / thirdparty / systemd.git / blobdiff