man/udev.conf.xml

   1 <?xml version='1.0'?>
   2 <!DOCTYPE refentry PUBLIC "-//OASIS//DTD DocBook XML V4.5//EN"
   3   "http://www.oasis-open.org/docbook/xml/4.5/docbookx.dtd">
   4 <!-- SPDX-License-Identifier: LGPL-2.1-or-later -->
   5
   6 <refentry id="udev.conf"
   7           xmlns:xi="http://www.w3.org/2001/XInclude">
   8
   9   <refentryinfo>
  10     <title>udev.conf</title>
  11     <productname>systemd</productname>
  12   </refentryinfo>
  13
  14   <refmeta>
  15     <refentrytitle>udev.conf</refentrytitle>
  16     <manvolnum>5</manvolnum>
  17   </refmeta>
  18
  19   <refnamediv>
  20     <refname>udev.conf</refname>
  21     <refname>udev.conf.d</refname>
  22     <refpurpose>Configuration for device event managing daemon</refpurpose>
  23   </refnamediv>
  24
  25   <refsynopsisdiv>
  26     <para>
  27       <simplelist>
  28         <member><filename>/etc/udev/udev.conf</filename></member>
  29         <member><filename>/run/udev/udev.conf</filename></member>
  30         <member><filename>/usr/lib/udev/udev.conf</filename></member>
  31         <member><filename>/etc/udev/udev.conf.d/*.conf</filename></member>
  32         <member><filename>/run/udev/udev.conf.d/*.conf</filename></member>
  33         <member><filename>/usr/lib/udev/udev.conf.d/*.conf</filename></member>
  34       </simplelist>
  35     </para>
  36   </refsynopsisdiv>
  37
  38   <refsect1>
  39     <title>Description</title>
  40
  41     <para>These files contain configuration options for
  42       <citerefentry><refentrytitle>systemd-udevd</refentrytitle><manvolnum>8</manvolnum></citerefentry>.
  43       The syntax of these files is very simple: a list
  44       of assignments, one per line.
  45       All empty lines or lines beginning with <literal>#</literal> are
  46       ignored.
  47     </para>
  48     <para>
  49       The following options can be set:
  50     </para>
  51
  52     <variablelist class='config-directives'>
  53       <varlistentry>
  54         <term><varname>udev_log=</varname></term>
  55
  56         <listitem>
  57           <para>The log level. Valid values are the numerical
  58           syslog priorities or their textual representations:
  59           <option>err</option>, <option>info</option> and
  60           <option>debug</option>.</para>
  61
  62           <note>
  63             <para>This option is also honored by
  64                 <citerefentry><refentrytitle>udevadm</refentrytitle><manvolnum>8</manvolnum></citerefentry>.
  65             </para>
  66           </note>
  67
  68           <xi:include href="version-info.xml" xpointer="v216"/>
  69         </listitem>
  70       </varlistentry>
  71
  72       <varlistentry>
  73         <term><varname>children_max=</varname></term>
  74
  75         <listitem>
  76           <para>An integer. The maximum number of events executed in parallel. When unspecified or 0 is
  77           specified, the maximum is determined based on the system resources.</para>
  78
  79           <para>This is the same as the <option>--children-max=</option> option.</para>
  80
  81           <xi:include href="version-info.xml" xpointer="v240"/>
  82         </listitem>
  83       </varlistentry>
  84
  85       <varlistentry>
  86         <term><varname>exec_delay=</varname></term>
  87
  88         <listitem>
  89           <para>An integer. Delay the execution of each <varname>RUN{<replaceable>program</replaceable>}</varname>
  90           parameter by the given number of seconds. This option
  91           might be useful when debugging system crashes during
  92           coldplug caused by loading non-working kernel
  93           modules.</para>
  94
  95           <para>This is the same as the <option>--exec-delay=</option> option.</para>
  96
  97           <xi:include href="version-info.xml" xpointer="v240"/>
  98         </listitem>
  99       </varlistentry>
 100
 101       <varlistentry>
 102         <term><varname>event_timeout=</varname></term>
 103
 104         <listitem>
 105           <para>An integer. The number of seconds to wait for events to finish. After
 106           this time, the event will be terminated. The default is 180 seconds.</para>
 107
 108           <para>This is the same as the <option>--event-timeout=</option> option.</para>
 109
 110           <xi:include href="version-info.xml" xpointer="v240"/>
 111         </listitem>
 112       </varlistentry>
 113
 114       <varlistentry>
 115         <term><varname>resolve_names=</varname></term>
 116
 117         <listitem>
 118           <para>Specifies when systemd-udevd should resolve names of users and groups.  When set to
 119           <option>early</option> (the default), names will be resolved when the rules are parsed.
 120           When set to <option>late</option>, names will be resolved for every event.  When set to
 121           <option>never</option>, names will never be resolved and all devices will be owned by
 122           root.</para>
 123
 124           <para>This is the same as the <option>--resolve-names=</option> option.</para>
 125
 126           <xi:include href="version-info.xml" xpointer="v240"/>
 127         </listitem>
 128       </varlistentry>
 129
 130       <varlistentry>
 131         <term><varname>timeout_signal=</varname></term>
 132
 133         <listitem>
 134           <para>Specifies a signal that <filename>systemd-udevd</filename> will send on worker
 135           timeouts. Note that both workers and spawned processes will be killed using this
 136           signal. Defaults to <option>SIGKILL</option>.</para>
 137
 138         <xi:include href="version-info.xml" xpointer="v246"/>
 139         </listitem>
 140       </varlistentry>
 141     </variablelist>
 142
 143     <para>
 144       In addition, <filename>systemd-udevd</filename> can be configured
 145       by command line options and the kernel command line (see
 146       <citerefentry><refentrytitle>systemd-udevd</refentrytitle><manvolnum>8</manvolnum></citerefentry>).
 147     </para>
 148   </refsect1>
 149
 150   <refsect1>
 151     <title>See Also</title>
 152     <para><simplelist type="inline">
 153       <member><citerefentry><refentrytitle>systemd-udevd</refentrytitle><manvolnum>8</manvolnum></citerefentry></member>
 154       <member><citerefentry><refentrytitle>udev</refentrytitle><manvolnum>7</manvolnum></citerefentry></member>
 155       <member><citerefentry><refentrytitle>udevadm</refentrytitle><manvolnum>8</manvolnum></citerefentry></member>
 156     </simplelist></para>
 157   </refsect1>
 158 </refentry>