1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
|
<?xml version='1.0'?> <!--*- Mode: nxml; nxml-child-indent: 2; indent-tabs-mode: nil -*-->
<!DOCTYPE refentry PUBLIC "-//OASIS//DTD DocBook XML V4.2//EN"
"http://www.oasis-open.org/docbook/xml/4.2/docbookx.dtd">
<refentry id="systemd-udevd.service"
xmlns:xi="http://www.w3.org/2001/XInclude">
<refentryinfo>
<title>systemd-udevd.service</title>
<productname>systemd</productname>
<authorgroup>
<author>
<contrib>Developer</contrib>
<firstname>Kay</firstname>
<surname>Sievers</surname>
<email>kay@vrfy.org</email>
</author>
</authorgroup>
</refentryinfo>
<refmeta>
<refentrytitle>systemd-udevd.service</refentrytitle>
<manvolnum>8</manvolnum>
</refmeta>
<refnamediv>
<refname>systemd-udevd.service</refname>
<refname>systemd-udevd-control.socket</refname>
<refname>systemd-udevd-kernel.socket</refname>
<refname>systemd-udevd</refname>
<refpurpose>Device event managing daemon</refpurpose>
</refnamediv>
<refsynopsisdiv>
<para><filename>systemd-udevd.service</filename></para>
<para><filename>systemd-udevd-control.socket</filename></para>
<para><filename>systemd-udevd-kernel.socket</filename></para>
<cmdsynopsis>
<command>/usr/lib/systemd/systemd-udevd</command>
<arg><option>--daemon</option></arg>
<arg><option>--debug</option></arg>
<arg><option>--children-max=</option></arg>
<arg><option>--exec-delay=</option></arg>
<arg><option>--event-timeout=</option></arg>
<arg><option>--resolve-names=early|late|never</option></arg>
<arg><option>--version</option></arg>
<arg><option>--help</option></arg>
</cmdsynopsis>
</refsynopsisdiv>
<refsect1><title>Description</title>
<para><command>systemd-udevd</command> listens to kernel uevents.
For every event, systemd-udevd executes matching instructions
specified in udev rules. See <citerefentry>
<refentrytitle>udev</refentrytitle><manvolnum>7</manvolnum>
</citerefentry>.</para>
<para>The behavior of the daemon can be configured using
<citerefentry><refentrytitle>udev.conf</refentrytitle><manvolnum>5</manvolnum></citerefentry>,
its command line options, environment variables, and on the kernel
command line, or changed dynamically with <command>udevadm
control</command>.
</para>
</refsect1>
<refsect1><title>Options</title>
<variablelist>
<varlistentry>
<term><option>--daemon</option></term>
<listitem>
<para>Detach and run in the background.</para>
</listitem>
</varlistentry>
<varlistentry>
<term><option>--debug</option></term>
<listitem>
<para>Print debug messages to standard error.</para>
</listitem>
</varlistentry>
<varlistentry>
<term><option>--children-max=</option></term>
<listitem>
<para>Limit the number of events executed in parallel.</para>
</listitem>
</varlistentry>
<varlistentry>
<term><option>--exec-delay=</option></term>
<listitem>
<para>Delay the execution of <varname>RUN</varname>
instructions by the given number of seconds. This option
might be useful when debugging system crashes during
coldplug caused by loading non-working kernel
modules.</para>
</listitem>
</varlistentry>
<varlistentry>
<term><option>--event-timeout=</option></term>
<listitem>
<para>Set the number of seconds to wait for events to finish. After
this time, the event will be terminated. The default is 180 seconds.</para>
</listitem>
</varlistentry>
<varlistentry>
<term><option>--resolve-names=</option></term>
<listitem>
<para>Specify when systemd-udevd should resolve names of users and groups.
When set to <option>early</option> (the default), names will be
resolved when the rules are parsed. When set to
<option>late</option>, names will be resolved for every event.
When set to <option>never</option>, names will never be resolved
and all devices will be owned by root.</para>
</listitem>
</varlistentry>
<varlistentry>
<term><option>--help</option></term>
<xi:include href="standard-options.xml" xpointer="help-text" />
</varlistentry>
<xi:include href="standard-options.xml" xpointer="version" />
</variablelist>
</refsect1>
<refsect1><title>Kernel command line</title>
<variablelist class='kernel-commandline-options'>
<para>Parameters starting with "rd." will be read when
<command>systemd-udevd</command> is used in an initrd.</para>
<varlistentry>
<term><varname>udev.log-priority=</varname></term>
<term><varname>rd.udev.log-priority=</varname></term>
<listitem>
<para>Set the log level.</para>
</listitem>
</varlistentry>
<varlistentry>
<term><varname>udev.children-max=</varname></term>
<term><varname>rd.udev.children-max=</varname></term>
<listitem>
<para>Limit the number of events executed in parallel.</para>
</listitem>
</varlistentry>
<varlistentry>
<term><varname>udev.exec-delay=</varname></term>
<term><varname>rd.udev.exec-delay=</varname></term>
<listitem>
<para>Delay the execution of <varname>RUN</varname> instructions by the given
number of seconds. This option might be useful when
debugging system crashes during coldplug caused by loading
non-working kernel modules.</para>
</listitem>
</varlistentry>
<varlistentry>
<term><varname>udev.event-timeout=</varname></term>
<term><varname>rd.udev.event-timeout=</varname></term>
<listitem>
<para>Wait for events to finish up to the given number
of seconds. This option might be useful if events are
terminated due to kernel drivers taking too long to initialize.</para>
</listitem>
</varlistentry>
<varlistentry>
<term><varname>net.ifnames=</varname></term>
<listitem>
<para>Network interfaces are renamed to give them predictable names
when possible. It is enabled by default; specifying 0 disables it.</para>
</listitem>
</varlistentry>
</variablelist>
<!-- when adding entries here, consider also adding them
in kernel-command-line.xml -->
</refsect1>
<refsect1>
<title>See Also</title>
<para>
<citerefentry><refentrytitle>udev.conf</refentrytitle><manvolnum>5</manvolnum></citerefentry>,
<citerefentry><refentrytitle>udev</refentrytitle><manvolnum>7</manvolnum></citerefentry>,
<citerefentry><refentrytitle>udevadm</refentrytitle><manvolnum>8</manvolnum></citerefentry>
</para>
</refsect1>
</refentry>
|
