- <para>Configuration is also read from a single configuration file in
- <filename>/etc/</filename>. This 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.</para>
+ <para>When packages need to customize the configuration, they can
+ install configuration snippets in
+ <filename>/usr/lib/elogind/*.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>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.</para>