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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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</style><a href="index.html">Index </a>·
<a href="systemd.directives.html">Directives </a>·
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<a href="../libudev/index.html">gudev </a><span style="float:right">systemd 215</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="idm214173617984"></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="idm214172493824"></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="idm214172649696"></a><h2 id="Example">Example<a class="headerlink" title="Permalink to this headline" href="#Example">¶</a></h2><div class="example"><a name="idm214173353776"></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="idm214172611440"></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="idm214172886672"></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="idm214173400832"></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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