1 <?xml version='1.0'?> <!--*-nxml-*-->
2 <!DOCTYPE refentry PUBLIC "-//OASIS//DTD DocBook XML V4.2//EN"
3 "http://www.oasis-open.org/docbook/xml/4.2/docbookx.dtd">
6 This file is part of systemd.
8 Copyright 2012 Lennart Poettering
10 systemd is free software; you can redistribute it and/or modify it
11 under the terms of the GNU Lesser General Public License as published by
12 the Free Software Foundation; either version 2.1 of the License, or
13 (at your option) any later version.
15 systemd is distributed in the hope that it will be useful, but
16 WITHOUT ANY WARRANTY; without even the implied warranty of
17 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
18 Lesser General Public License for more details.
20 You should have received a copy of the GNU Lesser General Public License
21 along with systemd; If not, see <http://www.gnu.org/licenses/>.
24 <refentry id="kernel-command-line">
27 <title>kernel-command-line</title>
28 <productname>systemd</productname>
32 <contrib>Developer</contrib>
33 <firstname>Lennart</firstname>
34 <surname>Poettering</surname>
35 <email>lennart@poettering.net</email>
41 <refentrytitle>kernel-command-line</refentrytitle>
42 <manvolnum>7</manvolnum>
46 <refname>kernel-command-line</refname>
47 <refpurpose>Kernel command line parameters</refpurpose>
51 <para><filename>/proc/cmdline</filename></para>
55 <title>Description</title>
57 <para>The kernel, the initial RAM disk (initrd) and
58 basic userspace functionality may be configured at boot via
59 kernel command line arguments.</para>
61 <para>For command line parameters understood by the
62 kernel, please see <ulink
63 url="https://www.kernel.org/doc/Documentation/kernel-parameters.txt"><filename>kernel-parameters.txt</filename></ulink>
65 <citerefentry><refentrytitle>bootparam</refentrytitle><manvolnum>7</manvolnum></citerefentry>.</para>
67 <para>For command line parameters understood by the
68 initial RAM disk, please see
69 <citerefentry><refentrytitle>dracut.cmdline</refentrytitle><manvolnum>7</manvolnum></citerefentry>,
70 or the documentation of the specific initrd
71 implementation of your installation.</para>
75 <title>Core OS Command Line Arguments</title>
77 <variablelist class='kernel-commandline-options'>
79 <term><varname>systemd.unit=</varname></term>
80 <term><varname>rd.systemd.unit=</varname></term>
81 <term><varname>systemd.dump_core=</varname></term>
82 <term><varname>systemd.crash_shell=</varname></term>
83 <term><varname>systemd.crash_chvt=</varname></term>
84 <term><varname>systemd.confirm_spawn=</varname></term>
85 <term><varname>systemd.show_status=</varname></term>
86 <term><varname>systemd.log_target=</varname></term>
87 <term><varname>systemd.log_level=</varname></term>
88 <term><varname>systemd.log_color=</varname></term>
89 <term><varname>systemd.log_location=</varname></term>
90 <term><varname>systemd.default_standard_output=</varname></term>
91 <term><varname>systemd.default_standard_error=</varname></term>
92 <term><varname>systemd.setenv=</varname></term>
94 <para>Parameters understood by
95 the system and service manager
96 to control system behavior. For details, see
97 <citerefentry><refentrytitle>systemd</refentrytitle><manvolnum>1</manvolnum></citerefentry>.</para>
102 <term><varname>systemd.restore_state=</varname></term>
104 <para>This parameter is understood by
105 several system tools to control
106 whether or not they should restore
107 system state from the previous boot.
109 <citerefentry><refentrytitle>systemd-backlight@.service</refentrytitle><manvolnum>8</manvolnum></citerefentry>
111 <citerefentry><refentrytitle>systemd-rfkill@.service</refentrytitle><manvolnum>8</manvolnum></citerefentry>.
117 <term><varname>quiet</varname></term>
119 <para>Parameter understood by
120 both the kernel and the system
121 and service manager to control
122 console log verbosity. For
124 <citerefentry><refentrytitle>systemd</refentrytitle><manvolnum>1</manvolnum></citerefentry>.</para>
129 <term><varname>debug</varname></term>
131 <para>Parameter understood by
132 both the kernel and the system
133 and service manager to control
134 console log verbosity. For
136 <citerefentry><refentrytitle>systemd</refentrytitle><manvolnum>1</manvolnum></citerefentry>.</para>
141 <term><varname>-b</varname></term>
142 <term><varname>emergency</varname></term>
143 <term><varname>single</varname></term>
144 <term><varname>s</varname></term>
145 <term><varname>S</varname></term>
146 <term><varname>1</varname></term>
147 <term><varname>2</varname></term>
148 <term><varname>3</varname></term>
149 <term><varname>4</varname></term>
150 <term><varname>5</varname></term>
152 <para>Parameters understood by
153 the system and service
154 manager, as compatibility
155 options. For details, see
156 <citerefentry><refentrytitle>systemd</refentrytitle><manvolnum>1</manvolnum></citerefentry>.</para>
161 <term><varname>locale.LANG=</varname></term>
162 <term><varname>locale.LANGUAGE=</varname></term>
163 <term><varname>locale.LC_CTYPE=</varname></term>
164 <term><varname>locale.LC_NUMERIC=</varname></term>
165 <term><varname>locale.LC_TIME=</varname></term>
166 <term><varname>locale.LC_COLLATE=</varname></term>
167 <term><varname>locale.LC_MONETARY=</varname></term>
168 <term><varname>locale.LC_MESSAGES=</varname></term>
169 <term><varname>locale.LC_PAPER=</varname></term>
170 <term><varname>locale.LC_NAME=</varname></term>
171 <term><varname>locale.LC_ADDRESS=</varname></term>
172 <term><varname>locale.LC_TELEPHONE=</varname></term>
173 <term><varname>locale.LC_MEASUREMENT=</varname></term>
174 <term><varname>locale.LC_IDENTIFICATION=</varname></term>
176 <para>Parameters understood by
177 the system and service manager
178 to control locale and language
179 settings. For details, see
180 <citerefentry><refentrytitle>systemd</refentrytitle><manvolnum>1</manvolnum></citerefentry>.</para>
185 <term><varname>fsck.mode=</varname></term>
188 <para>Parameter understood by
189 the file system checker
190 services. For details, see
191 <citerefentry><refentrytitle>systemd-fsck@.service</refentrytitle><manvolnum>8</manvolnum></citerefentry>.</para>
196 <term><varname>quotacheck.mode=</varname></term>
199 <para>Parameter understood by
200 the file quota checker
201 service. For details, see
202 <citerefentry><refentrytitle>systemd-quotacheck.service</refentrytitle><manvolnum>8</manvolnum></citerefentry>.</para>
207 <term><varname>systemd.journald.forward_to_syslog=</varname></term>
208 <term><varname>systemd.journald.forward_to_kmsg=</varname></term>
209 <term><varname>systemd.journald.forward_to_console=</varname></term>
210 <term><varname>systemd.journald.forward_to_wall=</varname></term>
213 <para>Parameters understood by
214 the journal service. For
216 <citerefentry><refentrytitle>systemd-journald.service</refentrytitle><manvolnum>8</manvolnum></citerefentry>.</para>
221 <term><varname>vconsole.keymap=</varname></term>
222 <term><varname>vconsole.keymap.toggle=</varname></term>
223 <term><varname>vconsole.font=</varname></term>
224 <term><varname>vconsole.font.map=</varname></term>
225 <term><varname>vconsole.font.unimap=</varname></term>
228 <para>Parameters understood by
229 the virtual console setup logic. For
231 <citerefentry><refentrytitle>systemd-vconsole-setup.service</refentrytitle><manvolnum>8</manvolnum></citerefentry>.</para>
236 <term><varname>udev.log-priority=</varname></term>
237 <term><varname>rd.udev.log-priority=</varname></term>
238 <term><varname>udev.children-max=</varname></term>
239 <term><varname>rd.udev.children-max=</varname></term>
240 <term><varname>udev.exec-delay=</varname></term>
241 <term><varname>rd.udev.exec-delay=</varname></term>
242 <term><varname>net.ifnames=</varname></term>
245 <para>Parameters understood by
246 the device event managing daemon. For
248 <citerefentry><refentrytitle>systemd-udevd.service</refentrytitle><manvolnum>8</manvolnum></citerefentry>.</para>
253 <term><varname>plymouth.enable=</varname></term>
256 <para>May be used to disable
257 the Plymouth boot splash. For
259 <citerefentry><refentrytitle>plymouth</refentrytitle><manvolnum>8</manvolnum></citerefentry>.</para>
264 <term><varname>luks=</varname></term>
265 <term><varname>rd.luks=</varname></term>
266 <term><varname>luks.crypttab=</varname></term>
267 <term><varname>rd.luks.crypttab=</varname></term>
268 <term><varname>luks.uuid=</varname></term>
269 <term><varname>rd.luks.uuid=</varname></term>
270 <term><varname>luks.options=</varname></term>
271 <term><varname>rd.luks.options=</varname></term>
272 <term><varname>luks.key=</varname></term>
273 <term><varname>rd.luks.key=</varname></term>
276 <para>Configures the LUKS
277 full-disk encryption logic at
278 boot. For details, see
279 <citerefentry><refentrytitle>systemd-cryptsetup-generator</refentrytitle><manvolnum>8</manvolnum></citerefentry>.</para>
284 <term><varname>fstab=</varname></term>
285 <term><varname>rd.fstab=</varname></term>
289 <filename>/etc/fstab</filename>
290 logic at boot. For details, see
291 <citerefentry><refentrytitle>systemd-fstab-generator</refentrytitle><manvolnum>8</manvolnum></citerefentry>.</para>
296 <term><varname>modules-load=</varname></term>
297 <term><varname>rd.modules-load=</varname></term>
300 <para>Load a specific kernel
301 module early at boot. For
303 <citerefentry><refentrytitle>systemd-modules-load.service</refentrytitle><manvolnum>8</manvolnum></citerefentry>.</para>
312 <title>See Also</title>
314 <citerefentry><refentrytitle>systemd</refentrytitle><manvolnum>1</manvolnum></citerefentry>,
315 <citerefentry><refentrytitle>bootparam</refentrytitle><manvolnum>7</manvolnum></citerefentry>,
316 <citerefentry><refentrytitle>dracut.cmdline</refentrytitle><manvolnum>7</manvolnum></citerefentry>,
317 <citerefentry><refentrytitle>systemd-fsck@.service</refentrytitle><manvolnum>8</manvolnum></citerefentry>,
318 <citerefentry><refentrytitle>systemd-quotacheck.service</refentrytitle><manvolnum>8</manvolnum></citerefentry>,
319 <citerefentry><refentrytitle>systemd-journald.service</refentrytitle><manvolnum>8</manvolnum></citerefentry>,
320 <citerefentry><refentrytitle>systemd-vconsole-setup.service</refentrytitle><manvolnum>8</manvolnum></citerefentry>,
321 <citerefentry><refentrytitle>systemd-udevd.service</refentrytitle><manvolnum>8</manvolnum></citerefentry>,
322 <citerefentry><refentrytitle>plymouth</refentrytitle><manvolnum>8</manvolnum></citerefentry>,
323 <citerefentry><refentrytitle>systemd-cryptsetup-generator</refentrytitle><manvolnum>8</manvolnum></citerefentry>,
324 <citerefentry><refentrytitle>systemd-fstab-generator</refentrytitle><manvolnum>8</manvolnum></citerefentry>,
325 <citerefentry><refentrytitle>systemd-modules-load.service</refentrytitle><manvolnum>8</manvolnum></citerefentry>
326 <citerefentry><refentrytitle>systemd-backlight@.service</refentrytitle><manvolnum>8</manvolnum></citerefentry>
327 <citerefentry><refentrytitle>systemd-rfkill@.service</refentrytitle><manvolnum>8</manvolnum></citerefentry>