man/kernel-command-line.xml

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   8   Copyright 2012 Lennart Poettering
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  23
  24 <refentry id="kernel-command-line">
  25
  26   <refentryinfo>
  27     <title>kernel-command-line</title>
  28     <productname>systemd</productname>
  29
  30     <authorgroup>
  31       <author>
  32         <contrib>Developer</contrib>
  33         <firstname>Lennart</firstname>
  34         <surname>Poettering</surname>
  35         <email>lennart@poettering.net</email>
  36       </author>
  37     </authorgroup>
  38   </refentryinfo>
  39
  40   <refmeta>
  41     <refentrytitle>kernel-command-line</refentrytitle>
  42     <manvolnum>7</manvolnum>
  43   </refmeta>
  44
  45   <refnamediv>
  46     <refname>kernel-command-line</refname>
  47     <refpurpose>Kernel command line parameters</refpurpose>
  48   </refnamediv>
  49
  50   <refsynopsisdiv>
  51     <para><filename>/proc/cmdline</filename></para>
  52   </refsynopsisdiv>
  53
  54   <refsect1>
  55     <title>Description</title>
  56
  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>
  60
  61     <para>For command line parameters understood by the kernel, please
  62     see <ulink
  63     url="https://www.kernel.org/doc/Documentation/kernel-parameters.txt"><filename>kernel-parameters.txt</filename></ulink>
  64     and
  65     <citerefentry project='man-pages'><refentrytitle>bootparam</refentrytitle><manvolnum>7</manvolnum></citerefentry>.</para>
  66
  67     <para>For command line parameters understood by the initial RAM
  68     disk, please see
  69     <citerefentry project='man-pages'><refentrytitle>dracut.cmdline</refentrytitle><manvolnum>7</manvolnum></citerefentry>,
  70     or the documentation of the specific initrd implementation of your
  71     installation.</para>
  72   </refsect1>
  73
  74   <refsect1>
  75     <title>Core OS Command Line Arguments</title>
  76
  77     <variablelist class='kernel-commandline-options'>
  78       <varlistentry>
  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_chvt=</varname></term>
  83         <term><varname>systemd.crash_shell=</varname></term>
  84         <term><varname>systemd.crash_reboot=</varname></term>
  85         <term><varname>systemd.confirm_spawn=</varname></term>
  86         <term><varname>systemd.show_status=</varname></term>
  87         <term><varname>systemd.log_target=</varname></term>
  88         <term><varname>systemd.log_level=</varname></term>
  89         <term><varname>systemd.log_color=</varname></term>
  90         <term><varname>systemd.log_location=</varname></term>
  91         <term><varname>systemd.default_standard_output=</varname></term>
  92         <term><varname>systemd.default_standard_error=</varname></term>
  93         <term><varname>systemd.setenv=</varname></term>
  94         <listitem>
  95           <para>Parameters understood by the system and service
  96           manager to control system behavior. For details, see
  97           <citerefentry><refentrytitle>systemd</refentrytitle><manvolnum>1</manvolnum></citerefentry>.</para>
  98         </listitem>
  99       </varlistentry>
 100
 101       <varlistentry>
 102         <term><varname>systemd.mask=</varname></term>
 103         <term><varname>systemd.wants=</varname></term>
 104         <term><varname>systemd.debug-shell</varname></term>
 105         <listitem>
 106           <para>Additional parameters understood by
 107           <citerefentry><refentrytitle>systemd-debug-generator</refentrytitle><manvolnum>8</manvolnum></citerefentry>,
 108           to mask or start specific units at boot, or invoke a debug
 109           shell on tty9.</para>
 110         </listitem>
 111       </varlistentry>
 112
 113       <varlistentry>
 114         <term><varname>systemd.restore_state=</varname></term>
 115         <listitem>
 116           <para>This parameter is understood by several system tools
 117           to control whether or not they should restore system state
 118           from the previous boot. For details, see
 119           <citerefentry><refentrytitle>systemd-backlight@.service</refentrytitle><manvolnum>8</manvolnum></citerefentry>
 120           and
 121           <citerefentry><refentrytitle>systemd-rfkill.service</refentrytitle><manvolnum>8</manvolnum></citerefentry>.
 122           </para>
 123         </listitem>
 124       </varlistentry>
 125
 126       <varlistentry>
 127         <term><varname>quiet</varname></term>
 128         <listitem>
 129           <para>Parameter understood by both the kernel and the system
 130           and service manager to control console log verbosity. For
 131           details, see
 132           <citerefentry><refentrytitle>systemd</refentrytitle><manvolnum>1</manvolnum></citerefentry>.</para>
 133         </listitem>
 134       </varlistentry>
 135
 136       <varlistentry>
 137         <term><varname>debug</varname></term>
 138         <listitem>
 139           <para>Parameter understood by both the kernel and the system
 140           and service manager to control console log verbosity. For
 141           details, see
 142           <citerefentry><refentrytitle>systemd</refentrytitle><manvolnum>1</manvolnum></citerefentry>.</para>
 143         </listitem>
 144       </varlistentry>
 145
 146       <varlistentry>
 147         <term><varname>-b</varname></term>
 148         <term><varname>emergency</varname></term>
 149         <term><varname>rescue</varname></term>
 150         <term><varname>single</varname></term>
 151         <term><varname>s</varname></term>
 152         <term><varname>S</varname></term>
 153         <term><varname>1</varname></term>
 154         <term><varname>2</varname></term>
 155         <term><varname>3</varname></term>
 156         <term><varname>4</varname></term>
 157         <term><varname>5</varname></term>
 158         <listitem>
 159           <para>Parameters understood by the system and service
 160           manager, as compatibility options. For details, see
 161           <citerefentry><refentrytitle>systemd</refentrytitle><manvolnum>1</manvolnum></citerefentry>.</para>
 162         </listitem>
 163       </varlistentry>
 164
 165       <varlistentry>
 166         <term><varname>locale.LANG=</varname></term>
 167         <term><varname>locale.LANGUAGE=</varname></term>
 168         <term><varname>locale.LC_CTYPE=</varname></term>
 169         <term><varname>locale.LC_NUMERIC=</varname></term>
 170         <term><varname>locale.LC_TIME=</varname></term>
 171         <term><varname>locale.LC_COLLATE=</varname></term>
 172         <term><varname>locale.LC_MONETARY=</varname></term>
 173         <term><varname>locale.LC_MESSAGES=</varname></term>
 174         <term><varname>locale.LC_PAPER=</varname></term>
 175         <term><varname>locale.LC_NAME=</varname></term>
 176         <term><varname>locale.LC_ADDRESS=</varname></term>
 177         <term><varname>locale.LC_TELEPHONE=</varname></term>
 178         <term><varname>locale.LC_MEASUREMENT=</varname></term>
 179         <term><varname>locale.LC_IDENTIFICATION=</varname></term>
 180         <listitem>
 181           <para>Parameters understood by the system and service
 182           manager to control locale and language settings. For
 183           details, see
 184           <citerefentry><refentrytitle>systemd</refentrytitle><manvolnum>1</manvolnum></citerefentry>.</para>
 185         </listitem>
 186       </varlistentry>
 187
 188       <varlistentry>
 189         <term><varname>fsck.mode=</varname></term>
 190         <term><varname>fsck.repair=</varname></term>
 191
 192         <listitem>
 193           <para>Parameters understood by the file system checker
 194           services. For details, see
 195           <citerefentry><refentrytitle>systemd-fsck@.service</refentrytitle><manvolnum>8</manvolnum></citerefentry>.</para>
 196         </listitem>
 197       </varlistentry>
 198
 199       <varlistentry>
 200         <term><varname>quotacheck.mode=</varname></term>
 201
 202         <listitem>
 203           <para>Parameter understood by the file quota checker
 204           service. For details, see
 205           <citerefentry><refentrytitle>systemd-quotacheck.service</refentrytitle><manvolnum>8</manvolnum></citerefentry>.</para>
 206         </listitem>
 207       </varlistentry>
 208
 209       <varlistentry>
 210         <term><varname>systemd.journald.forward_to_syslog=</varname></term>
 211         <term><varname>systemd.journald.forward_to_kmsg=</varname></term>
 212         <term><varname>systemd.journald.forward_to_console=</varname></term>
 213         <term><varname>systemd.journald.forward_to_wall=</varname></term>
 214
 215         <listitem>
 216           <para>Parameters understood by the journal service. For
 217           details, see
 218           <citerefentry><refentrytitle>systemd-journald.service</refentrytitle><manvolnum>8</manvolnum></citerefentry>.</para>
 219         </listitem>
 220       </varlistentry>
 221
 222       <varlistentry>
 223         <term><varname>vconsole.keymap=</varname></term>
 224         <term><varname>vconsole.keymap.toggle=</varname></term>
 225         <term><varname>vconsole.font=</varname></term>
 226         <term><varname>vconsole.font.map=</varname></term>
 227         <term><varname>vconsole.font.unimap=</varname></term>
 228
 229         <listitem>
 230           <para>Parameters understood by the virtual console setup
 231           logic. For details, see
 232           <citerefentry><refentrytitle>systemd-vconsole-setup.service</refentrytitle><manvolnum>8</manvolnum></citerefentry>.</para>
 233         </listitem>
 234       </varlistentry>
 235
 236       <varlistentry>
 237         <term><varname>udev.log-priority=</varname></term>
 238         <term><varname>rd.udev.log-priority=</varname></term>
 239         <term><varname>udev.children-max=</varname></term>
 240         <term><varname>rd.udev.children-max=</varname></term>
 241         <term><varname>udev.exec-delay=</varname></term>
 242         <term><varname>rd.udev.exec-delay=</varname></term>
 243         <term><varname>udev.event-timeout=</varname></term>
 244         <term><varname>rd.udev.event-timeout=</varname></term>
 245         <term><varname>net.ifnames=</varname></term>
 246
 247         <listitem>
 248           <para>Parameters understood by the device event managing
 249           daemon. For details, see
 250           <citerefentry><refentrytitle>systemd-udevd.service</refentrytitle><manvolnum>8</manvolnum></citerefentry>.</para>
 251         </listitem>
 252       </varlistentry>
 253
 254       <varlistentry>
 255         <term><varname>plymouth.enable=</varname></term>
 256
 257         <listitem>
 258           <para>May be used to disable the Plymouth boot splash. For
 259           details, see
 260           <citerefentry project='die-net'><refentrytitle>plymouth</refentrytitle><manvolnum>8</manvolnum></citerefentry>.</para>
 261         </listitem>
 262       </varlistentry>
 263
 264       <varlistentry>
 265         <term><varname>luks=</varname></term>
 266         <term><varname>rd.luks=</varname></term>
 267         <term><varname>luks.crypttab=</varname></term>
 268         <term><varname>rd.luks.crypttab=</varname></term>
 269         <term><varname>luks.name=</varname></term>
 270         <term><varname>rd.luks.name=</varname></term>
 271         <term><varname>luks.uuid=</varname></term>
 272         <term><varname>rd.luks.uuid=</varname></term>
 273         <term><varname>luks.options=</varname></term>
 274         <term><varname>rd.luks.options=</varname></term>
 275         <term><varname>luks.key=</varname></term>
 276         <term><varname>rd.luks.key=</varname></term>
 277
 278         <listitem>
 279           <para>Configures the LUKS full-disk encryption logic at
 280           boot. For details, see
 281           <citerefentry><refentrytitle>systemd-cryptsetup-generator</refentrytitle><manvolnum>8</manvolnum></citerefentry>.</para>
 282         </listitem>
 283       </varlistentry>
 284
 285       <varlistentry>
 286         <term><varname>fstab=</varname></term>
 287         <term><varname>rd.fstab=</varname></term>
 288
 289         <listitem>
 290           <para>Configures the <filename>/etc/fstab</filename> logic
 291           at boot. For details, see
 292           <citerefentry><refentrytitle>systemd-fstab-generator</refentrytitle><manvolnum>8</manvolnum></citerefentry>.</para>
 293         </listitem>
 294       </varlistentry>
 295
 296       <varlistentry>
 297         <term><varname>root=</varname></term>
 298         <term><varname>rootfstype=</varname></term>
 299         <term><varname>rootflags=</varname></term>
 300         <term><varname>ro</varname></term>
 301         <term><varname>rw</varname></term>
 302
 303         <listitem>
 304           <para>Configures the root file system and its file system
 305           type and mount options, as well as whether it shall be
 306           mounted read-only or read-writable initially. For details,
 307           see
 308           <citerefentry><refentrytitle>systemd-fstab-generator</refentrytitle><manvolnum>8</manvolnum></citerefentry>.</para>
 309         </listitem>
 310       </varlistentry>
 311
 312       <varlistentry>
 313         <term><varname>systemd.gpt_auto=</varname></term>
 314         <term><varname>rd.systemd.gpt_auto=</varname></term>
 315
 316         <listitem>
 317           <para>Configures whether GPT based partition auto-discovery
 318           shall be attempted. For details, see
 319           <citerefentry><refentrytitle>systemd-gpt-auto-generator</refentrytitle><manvolnum>8</manvolnum></citerefentry>.</para>
 320         </listitem>
 321       </varlistentry>
 322
 323       <varlistentry>
 324         <term><varname>modules-load=</varname></term>
 325         <term><varname>rd.modules-load=</varname></term>
 326
 327         <listitem>
 328           <para>Load a specific kernel module early at boot. For
 329           details, see
 330           <citerefentry><refentrytitle>systemd-modules-load.service</refentrytitle><manvolnum>8</manvolnum></citerefentry>.</para>
 331         </listitem>
 332       </varlistentry>
 333
 334       <varlistentry>
 335         <term><varname>resume=</varname></term>
 336
 337         <listitem>
 338           <para>Enables resume from hibernation using the specified
 339           device. All
 340           <citerefentry project='man-pages'><refentrytitle>fstab</refentrytitle><manvolnum>5</manvolnum></citerefentry>-like
 341           paths are supported. For details, see
 342           <citerefentry><refentrytitle>systemd-hibernate-resume-generator</refentrytitle><manvolnum>8</manvolnum></citerefentry>.</para>
 343         </listitem>
 344       </varlistentry>
 345     </variablelist>
 346
 347   </refsect1>
 348
 349   <refsect1>
 350       <title>See Also</title>
 351       <para>
 352         <citerefentry><refentrytitle>systemd</refentrytitle><manvolnum>1</manvolnum></citerefentry>,
 353         <citerefentry project='man-pages'><refentrytitle>bootparam</refentrytitle><manvolnum>7</manvolnum></citerefentry>,
 354         <citerefentry project='man-pages'><refentrytitle>dracut.cmdline</refentrytitle><manvolnum>7</manvolnum></citerefentry>,
 355         <citerefentry><refentrytitle>systemd-debug-generator</refentrytitle><manvolnum>8</manvolnum></citerefentry>,
 356         <citerefentry><refentrytitle>systemd-fsck@.service</refentrytitle><manvolnum>8</manvolnum></citerefentry>,
 357         <citerefentry><refentrytitle>systemd-quotacheck.service</refentrytitle><manvolnum>8</manvolnum></citerefentry>,
 358         <citerefentry><refentrytitle>systemd-journald.service</refentrytitle><manvolnum>8</manvolnum></citerefentry>,
 359         <citerefentry><refentrytitle>systemd-vconsole-setup.service</refentrytitle><manvolnum>8</manvolnum></citerefentry>,
 360         <citerefentry><refentrytitle>systemd-udevd.service</refentrytitle><manvolnum>8</manvolnum></citerefentry>,
 361         <citerefentry project='die-net'><refentrytitle>plymouth</refentrytitle><manvolnum>8</manvolnum></citerefentry>,
 362         <citerefentry><refentrytitle>systemd-cryptsetup-generator</refentrytitle><manvolnum>8</manvolnum></citerefentry>,
 363         <citerefentry><refentrytitle>systemd-fstab-generator</refentrytitle><manvolnum>8</manvolnum></citerefentry>,
 364         <citerefentry><refentrytitle>systemd-gpt-auto-generator</refentrytitle><manvolnum>8</manvolnum></citerefentry>,
 365         <citerefentry><refentrytitle>systemd-modules-load.service</refentrytitle><manvolnum>8</manvolnum></citerefentry>,
 366         <citerefentry><refentrytitle>systemd-backlight@.service</refentrytitle><manvolnum>8</manvolnum></citerefentry>,
 367         <citerefentry><refentrytitle>systemd-rfkill.service</refentrytitle><manvolnum>8</manvolnum></citerefentry>,
 368         <citerefentry><refentrytitle>systemd-hibernate-resume-generator</refentrytitle><manvolnum>8</manvolnum></citerefentry>
 369       </para>
 370   </refsect1>
 371
 372 </refentry>