man/systemd-udevd.html

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  22   <a href="../libudev/index.html">gudev </a><span style="float:right">systemd 218</span><hr><div class="refentry"><a name="systemd-udevd.service"></a><div class="titlepage"></div><div class="refnamediv"><h2>Name</h2><p>systemd-udevd.service, systemd-udevd-control.socket, systemd-udevd-kernel.socket, systemd-udevd — Device event managing daemon</p></div><div class="refsynopsisdiv"><h2>Synopsis</h2><p><code class="filename">systemd-udevd.service</code></p><p><code class="filename">systemd-udevd-control.socket</code></p><p><code class="filename">systemd-udevd-kernel.socket</code></p><div class="cmdsynopsis"><p><code class="command">/usr/lib/systemd/systemd-udevd</code>  [<code class="option">--daemon</code>] [<code class="option">--debug</code>] [<code class="option">--children-max=</code>] [<code class="option">--exec-delay=</code>] [<code class="option">--event-timeout=</code>] [<code class="option">--resolve-names=early|late|never</code>] [<code class="option">--version</code>] [<code class="option">--help</code>]</p></div></div><div class="refsect1"><a name="idm140098489756448"></a><h2 id="Description">Description<a class="headerlink" title="Permalink to this headline" href="#Description">¶</a></h2><p><span class="command"><strong>systemd-udevd</strong></span> listens to kernel uevents.
  23     For every event, systemd-udevd executes matching instructions
  24     specified in udev rules. See <a href="udev.html"><span class="citerefentry"><span class="refentrytitle">udev</span>(7)</span></a>.</p><p>The behavior of the daemon can be configured using
  25     <a href="udev.conf.html"><span class="citerefentry"><span class="refentrytitle">udev.conf</span>(5)</span></a>,
  26     its command line options, environment variables, and on the kernel
  27     command line, or changed dynamically with <span class="command"><strong>udevadm
  28     control</strong></span>.
  29     </p></div><div class="refsect1"><a name="idm140098493656368"></a><h2 id="Options">Options<a class="headerlink" title="Permalink to this headline" href="#Options">¶</a></h2><div class="variablelist"><dl class="variablelist"><dt id="--daemon"><span class="term"><code class="option">--daemon</code></span><a class="headerlink" title="Permalink to this term" href="#--daemon">¶</a></dt><dd><p>Detach and run in the background.</p></dd><dt id="--debug"><span class="term"><code class="option">--debug</code></span><a class="headerlink" title="Permalink to this term" href="#--debug">¶</a></dt><dd><p>Print debug messages to standard error.</p></dd><dt id="--children-max="><span class="term"><code class="option">--children-max=</code></span><a class="headerlink" title="Permalink to this term" href="#--children-max=">¶</a></dt><dd><p>Limit the number of events executed in parallel.</p></dd><dt id="--exec-delay="><span class="term"><code class="option">--exec-delay=</code></span><a class="headerlink" title="Permalink to this term" href="#--exec-delay=">¶</a></dt><dd><p>Delay the execution of <code class="varname">RUN</code>
  30           instructions by the given number of seconds. This option
  31           might be useful when debugging system crashes during
  32           coldplug caused by loading non-working kernel
  33           modules.</p></dd><dt id="--event-timeout="><span class="term"><code class="option">--event-timeout=</code></span><a class="headerlink" title="Permalink to this term" href="#--event-timeout=">¶</a></dt><dd><p>Set the number of seconds to wait for events to finish. After
  34           this time the event will be terminated. The default is 30 seconds.</p></dd><dt id="--resolve-names="><span class="term"><code class="option">--resolve-names=</code></span><a class="headerlink" title="Permalink to this term" href="#--resolve-names=">¶</a></dt><dd><p>Specify when systemd-udevd should resolve names of users and groups.
  35           When set to <code class="option">early</code> (the default), names will be
  36           resolved when the rules are parsed.  When set to
  37           <code class="option">late</code>, names will be resolved for every event.
  38           When set to <code class="option">never</code>, names will never be resolved
  39           and all devices will be owned by root.</p></dd><dt id="--help"><span class="term"><code class="option">--help</code></span><a class="headerlink" title="Permalink to this term" href="#--help">¶</a></dt><dd><p><a name="help-text"></a>Print a short help text and exit.
  40     </p></dd><dt id="--version"><span class="term"><code class="option">--version</code></span><a class="headerlink" title="Permalink to this term" href="#--version">¶</a></dt><dd><p><a name="version-text"></a>Print a short version string and exit.</p></dd></dl></div></div><div class="refsect1"><a name="idm140098493632736"></a><h2 id="Kernel command line">Kernel command line<a class="headerlink" title="Permalink to this headline" href="#Kernel%20command%20line">¶</a></h2><div class="variablelist"><p>Parameters starting with "rd." will be read when
  41       <span class="command"><strong>systemd-udevd</strong></span> is used in an initrd.</p><dl class="variablelist"><dt id="udev.log-priority="><span class="term"><code class="varname">udev.log-priority=</code>, </span><span class="term"><code class="varname">rd.udev.log-priority=</code></span><a class="headerlink" title="Permalink to this term" href="#udev.log-priority=">¶</a></dt><dd><p>Set the log level.</p></dd><dt id="udev.children-max="><span class="term"><code class="varname">udev.children-max=</code>, </span><span class="term"><code class="varname">rd.udev.children-max=</code></span><a class="headerlink" title="Permalink to this term" href="#udev.children-max=">¶</a></dt><dd><p>Limit the number of events executed in parallel.</p></dd><dt id="udev.exec-delay="><span class="term"><code class="varname">udev.exec-delay=</code>, </span><span class="term"><code class="varname">rd.udev.exec-delay=</code></span><a class="headerlink" title="Permalink to this term" href="#udev.exec-delay=">¶</a></dt><dd><p>Delay the execution of <code class="varname">RUN</code> instructions by the given
  42           number of seconds. This option might be useful when
  43           debugging system crashes during coldplug caused by loading
  44           non-working kernel modules.</p></dd><dt id="udev.event-timeout="><span class="term"><code class="varname">udev.event-timeout=</code>, </span><span class="term"><code class="varname">rd.udev.event-timeout=</code></span><a class="headerlink" title="Permalink to this term" href="#udev.event-timeout=">¶</a></dt><dd><p>Wait for events to finish up to the given number
  45           of seconds. This option might be useful if events are
  46           terminated due to kernel drivers taking too long to initialize.</p></dd><dt id="net.ifnames="><span class="term"><code class="varname">net.ifnames=</code></span><a class="headerlink" title="Permalink to this term" href="#net.ifnames=">¶</a></dt><dd><p>Network interfaces are renamed to give them predictable names
  47           when possible. It is enabled by default; specifying 0 disables it.</p></dd></dl></div></div><div class="refsect1"><a name="idm140098493618144"></a><h2 id="See Also">See Also<a class="headerlink" title="Permalink to this headline" href="#See%20Also">¶</a></h2><p>
  48       <a href="udev.conf.html"><span class="citerefentry"><span class="refentrytitle">udev.conf</span>(5)</span></a>,
  49       <a href="udev.html"><span class="citerefentry"><span class="refentrytitle">udev</span>(7)</span></a>,
  50       <a href="udevadm.html"><span class="citerefentry"><span class="refentrytitle">udevadm</span>(8)</span></a>
  51     </p></div></div></body></html>