<title>Description</title>
<para><command>systemd-sysusers</command> uses the
- files from <filename>/usr/lib/sysusers.d/</filename>
+ files from <filename>sysusers.d</filename> directory
to create system users and groups at package
- installation or boot time. This tool may be used for
- allocating system users and groups only, it is not
+ installation or boot time. This tool may be used to
+ allocate system users and groups only, it is not
useful for creating non-system users and groups, as it
- accessed <filename>/etc/passwd</filename> and
+ accesses <filename>/etc/passwd</filename> and
<filename>/etc/group</filename> directly, bypassing
- any more complex user database, for example any
+ any more complex user databases, for example any
database involving NIS or LDAP.</para>
-
</refsect1>
<refsect1>
- <title>File Format</title>
-
- <para>Each file shall be named in the style of
- <filename><replaceable>package</replaceable>.conf</filename>.</para>
+ <title>Configuration Format</title>
- <para>All files are sorted by their filename in
- lexicographic order, regardless of which of the
- directories they reside in. If multiple files specify
- the same user or group, the entry in the file with the
- lexicographically earliest name will be applied, all
- all other conflicting entries will be logged as
- errors. Users and groups are
- processed in the order they are listed.</para>
+ <para>Each configuration file shall be named in the
+ style of
+ <filename><replaceable>package</replaceable>.conf</filename>
+ or
+ <filename><replaceable>package</replaceable>-<replaceable>part</replaceable>.conf</filename>.
+ The second variant should be used when it is desirable
+ to make it easy to override just this part of
+ configuration.</para>
<para>The file format is one line per user or group
containing name, ID and GECOS field description:</para>
group will be set to the group
bearing the same name. The
user's shell will be set to
- <filename>/sbin/login</filename>,
+ <filename>/sbin/nologin</filename>,
the home directory to
<filename>/</filename>. The
account will be created
<title>Name</title>
<para>The name field specifies the user or
- group name. It should be be shorter than 256
+ group name. It should be shorter than 31
characters and avoid any non-ASCII characters,
and not begin with a numeric character. It is
strongly recommended to pick user and group
</refsect1>
+ <refsect1>
+ <title>Overriding vendor configuration</title>
+
+ <para>Note that <command>systemd-sysusers</command>
+ will do nothing if the specified users or groups
+ already exist, so normally there no reason to override
+ <filename>sysusers.d</filename> vendor configuration,
+ except to block certain users or groups from being
+ created.</para>
+
+ <para>Files in <filename>/etc/sysusers.d</filename>
+ override files with the same name in
+ <filename>/usr/lib/sysusers.d</filename> and
+ <filename>/run/sysusers.d</filename>. Files in
+ <filename>/run/sysusers.d</filename> override files
+ with the same name in
+ <filename>/usr/lib/sysusers.d</filename>. The scheme is the same as for
+ <citerefentry><refentrytitle>tmpfiles.d</refentrytitle><manvolnum>5</manvolnum></citerefentry>,
+ except for the directory name.</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
+ <filename>/etc/sysusers.d/</filename> bearing the
+ same filename.</para>
+ </refsect1>
+
<refsect1>
<title>See Also</title>
<para>
<citerefentry><refentrytitle>systemd</refentrytitle><manvolnum>1</manvolnum></citerefentry>,
- <citerefentry><refentrytitle>systemd-sysusers</refentrytitle><manvolnum>8</manvolnum></citerefentry>
+ <citerefentry><refentrytitle>systemd-sysusers</refentrytitle><manvolnum>8</manvolnum></citerefentry>,
+ <citerefentry><refentrytitle>tmpfiles.d</refentrytitle><manvolnum>5</manvolnum></citerefentry>
</para>
</refsect1>