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<html><head><meta http-equiv="Content-Type" content="text/html; charset=UTF-8"><title>systemd.preset</title><meta name="generator" content="DocBook XSL Stylesheets V1.78.1"></head><body bgcolor="white" text="black" link="#0000FF" vlink="#840084" alink="#0000FF"><style>
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<span style="float:right">systemd 221</span><hr><div class="refentry"><a name="systemd.preset"></a><div class="titlepage"></div><div class="refnamediv"><h2>Name</h2><p>systemd.preset — Service enablement presets</p></div><div class="refsynopsisdiv"><h2>Synopsis</h2><p><code class="filename">/etc/systemd/system-preset/*.preset</code></p><p><code class="filename">/run/systemd/system-preset/*.preset</code></p><p><code class="filename">/usr/lib/systemd/system-preset/*.preset</code></p><p><code class="filename">/etc/systemd/user-preset/*.preset</code></p><p><code class="filename">/run/systemd/user-preset/*.preset</code></p><p><code class="filename">/usr/lib/systemd/user-preset/*.preset</code></p></div><div class="refsect1"><a name="idm47134263530608"></a><h2 id="Description">Description<a class="headerlink" title="Permalink to this headline" href="#Description">¶</a></h2><p>Preset files may be used to encode policy which units shall
be enabled by default and which ones shall be disabled. They are
read by <span class="command"><strong>systemctl preset</strong></span> (for more information
see
<a href="systemctl.html"><span class="citerefentry"><span class="refentrytitle">systemctl</span>(1)</span></a>)
which uses this information to enable or disable a unit according
to preset policy. <span class="command"><strong>systemctl preset</strong></span> is used by
the post install scriptlets of RPM packages (or other OS package
formats), to enable/disable specific units by default on package
installation, enforcing distribution, spin or administrator preset
policy. This allows choosing a certain set of units to be
enabled/disabled even before installing the actual package.</p><p>For more information on the preset logic please have a look
at the <a class="ulink" href="http://freedesktop.org/wiki/Software/systemd/Preset" target="_top">Presets</a>
document.</p><p>It is not recommended to ship preset files within the
respective software packages implementing the units, but rather
centralize them in a distribution or spin default policy, which
can be amended by administrator policy.</p><p>If no preset files exist, <span class="command"><strong>systemctl
preset</strong></span> will enable all units that are installed by
default. If this is not desired and all units shall rather be
disabled, it is necessary to ship a preset file with a single,
catchall "<code class="filename">disable *</code>" line. (See example 1,
below.)</p></div><div class="refsect1"><a name="idm47134258621904"></a><h2 id="Preset File Format">Preset File Format<a class="headerlink" title="Permalink to this headline" href="#Preset%20File%20Format">¶</a></h2><p>The preset files contain a list of directives consisting of
either the word "<code class="literal">enable</code>" or
"<code class="literal">disable</code>" followed by a space and a unit name
(possibly with shell style wildcards), separated by newlines.
Empty lines and lines whose first non-whitespace character is # or
; are ignored.</p><p>Two different directives are understood:
"<code class="literal">enable</code>" may be used to enable units by default,
"<code class="literal">disable</code>" to disable units by default.</p><p>If multiple lines apply to a unit name, the first matching
one takes precedence over all others.</p><p>Each preset file shall be named in the style of
<code class="filename"><priority>-<program>.conf</code>. Files
in <code class="filename">/etc/</code> override files with the same name in
<code class="filename">/usr/lib/</code> and <code class="filename">/run/</code>.
Files in <code class="filename">/run/</code> override files with the same
name in <code class="filename">/usr/lib/</code>. Packages should install
their preset files in <code class="filename">/usr/lib/</code>. Files in
<code class="filename">/etc/</code> are reserved for the local
administrator, who may use this logic to override the preset files
installed by vendor packages. All preset files are sorted by their
filename in lexicographic order, regardless of which of the
directories they reside in. If multiple files specify the same
unit name, the entry in the file with the lexicographically
earliest name will be applied. It is recommended to prefix all
filenames with a two-digit number and a dash, to simplify the
ordering of the files.</p><p>If the administrator wants to disable a preset file supplied
by the vendor, the recommended way is to place a symlink to
<code class="filename">/dev/null</code> in
<code class="filename">/etc/systemd/system-preset/</code> bearing the same
filename.</p></div><div class="refsect1"><a name="idm47134258609472"></a><h2 id="Example">Example<a class="headerlink" title="Permalink to this headline" href="#Example">¶</a></h2><div class="example"><a name="idm47134258608832"></a><p class="title"><b>Example 1. Default off example <code class="filename">/usr/lib/systemd/system-preset/99-default.preset</code>:</b></p><div class="example-contents"><pre class="programlisting">disable *</pre></div></div><br class="example-break"><p>This disables all units. Due to the filename prefix
"<code class="literal">99-</code>", it will be read last and hence can easily
be overridden by spin or administrator preset policy or
suchlike.</p><div class="example"><a name="idm47134258605680"></a><p class="title"><b>Example 2. A GNOME spin example <code class="filename">/usr/lib/systemd/system-preset/50-gnome.preset</code>:</b></p><div class="example-contents"><pre class="programlisting">enable gdm.service
enable colord.service
enable accounts-daemon.service
enable avahi-daemon.*</pre></div></div><br class="example-break"><p>This enables the three mentioned units, plus all
<code class="filename">avahi-daemon</code> regardless of which unit type. A
file like this could be useful for inclusion in a GNOME spin of a
distribution. It will ensure that the units necessary for GNOME
are properly enabled as they are installed. It leaves all other
units untouched, and subject to other (later) preset files, for
example like the one from the first example above.</p><div class="example"><a name="idm47134258602160"></a><p class="title"><b>Example 3. Administrator policy <code class="filename">/etc/systemd/system-preset/00-lennart.preset</code>:</b></p><div class="example-contents"><pre class="programlisting">enable httpd.service
enable sshd.service
enable postfix.service
disable *</pre></div></div><br class="example-break"><p>This enables three specific services and disables all
others. This is useful for administrators to specifically select
the units to enable, and disable all others. Due to the filename
prefix "<code class="literal">00-</code>" it will be read early and hence
overrides all other preset policy files.</p></div><div class="refsect1"><a name="idm47134258598688"></a><h2 id="See Also">See Also<a class="headerlink" title="Permalink to this headline" href="#See%20Also">¶</a></h2><p>
<a href="systemd.html"><span class="citerefentry"><span class="refentrytitle">systemd</span>(1)</span></a>,
<a href="systemctl.html"><span class="citerefentry"><span class="refentrytitle">systemctl</span>(1)</span></a>,
<a href="systemd-delta.html"><span class="citerefentry"><span class="refentrytitle">systemd-delta</span>(1)</span></a>
</p></div></div></body></html>
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