man/kernel-command-line.xml

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   6   This file is part of systemd.
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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
  62                 kernel, please see <ulink
  63                 url="https://www.kernel.org/doc/Documentation/kernel-parameters.txt"><filename>kernel-parameters.txt</filename></ulink>
  64                 and
  65                 <citerefentry><refentrytitle>bootparam</refentrytitle><manvolnum>7</manvolnum></citerefentry>.</para>
  66
  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>
  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_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>
  93                                 <listitem>
  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>
  98                                 </listitem>
  99                         </varlistentry>
 100
 101                         <varlistentry>
 102                                 <term><varname>systemd.restore_state=</varname></term>
 103                                 <listitem>
 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.
 108                                         For details, see
 109                                         <citerefentry><refentrytitle>systemd-backlight@.service</refentrytitle><manvolnum>8</manvolnum></citerefentry>
 110                                         and
 111                                         <citerefentry><refentrytitle>systemd-rfkill@.service</refentrytitle><manvolnum>8</manvolnum></citerefentry>.
 112                                         </para>
 113                                 </listitem>
 114                         </varlistentry>
 115
 116                         <varlistentry>
 117                                 <term><varname>quiet</varname></term>
 118                                 <listitem>
 119                                         <para>Parameter understood by
 120                                         both the kernel and the system
 121                                         and service manager to control
 122                                         console log verbosity. For
 123                                         details, see
 124                                         <citerefentry><refentrytitle>systemd</refentrytitle><manvolnum>1</manvolnum></citerefentry>.</para>
 125                                 </listitem>
 126                         </varlistentry>
 127
 128                         <varlistentry>
 129                                 <term><varname>debug</varname></term>
 130                                 <listitem>
 131                                         <para>Parameter understood by
 132                                         both the kernel and the system
 133                                         and service manager to control
 134                                         console log verbosity. For
 135                                         details, see
 136                                         <citerefentry><refentrytitle>systemd</refentrytitle><manvolnum>1</manvolnum></citerefentry>.</para>
 137                                 </listitem>
 138                         </varlistentry>
 139
 140                         <varlistentry>
 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>
 151                                 <listitem>
 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>
 157                                 </listitem>
 158                         </varlistentry>
 159
 160                         <varlistentry>
 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>
 175                                 <listitem>
 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>
 181                                 </listitem>
 182                         </varlistentry>
 183
 184                         <varlistentry>
 185                                 <term><varname>fsck.mode=</varname></term>
 186
 187                                 <listitem>
 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>
 192                                 </listitem>
 193                         </varlistentry>
 194
 195                         <varlistentry>
 196                                 <term><varname>quotacheck.mode=</varname></term>
 197
 198                                 <listitem>
 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>
 203                                 </listitem>
 204                         </varlistentry>
 205
 206                         <varlistentry>
 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>
 211
 212                                 <listitem>
 213                                         <para>Parameters understood by
 214                                         the journal service. For
 215                                         details, see
 216                                         <citerefentry><refentrytitle>systemd-journald.service</refentrytitle><manvolnum>8</manvolnum></citerefentry>.</para>
 217                                 </listitem>
 218                         </varlistentry>
 219
 220                         <varlistentry>
 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>
 226
 227                                 <listitem>
 228                                         <para>Parameters understood by
 229                                         the virtual console setup logic. For
 230                                         details, see
 231                                         <citerefentry><refentrytitle>systemd-vconsole-setup.service</refentrytitle><manvolnum>8</manvolnum></citerefentry>.</para>
 232                                 </listitem>
 233                         </varlistentry>
 234
 235                         <varlistentry>
 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>
 243
 244                                 <listitem>
 245                                         <para>Parameters understood by
 246                                         the device event managing daemon. For
 247                                         details, see
 248                                         <citerefentry><refentrytitle>systemd-udevd.service</refentrytitle><manvolnum>8</manvolnum></citerefentry>.</para>
 249                                 </listitem>
 250                         </varlistentry>
 251
 252                         <varlistentry>
 253                                 <term><varname>plymouth.enable=</varname></term>
 254
 255                                 <listitem>
 256                                         <para>May be used to disable
 257                                         the Plymouth boot splash. For
 258                                         details, see
 259                                         <citerefentry><refentrytitle>plymouth</refentrytitle><manvolnum>8</manvolnum></citerefentry>.</para>
 260                                 </listitem>
 261                         </varlistentry>
 262
 263                         <varlistentry>
 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>
 274
 275                                 <listitem>
 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>
 280                                 </listitem>
 281                         </varlistentry>
 282
 283                         <varlistentry>
 284                                 <term><varname>fstab=</varname></term>
 285                                 <term><varname>rd.fstab=</varname></term>
 286
 287                                 <listitem>
 288                                         <para>Configures the
 289                                         <filename>/etc/fstab</filename>
 290                                         logic at boot. For details, see
 291                                         <citerefentry><refentrytitle>systemd-fstab-generator</refentrytitle><manvolnum>8</manvolnum></citerefentry>.</para>
 292                                 </listitem>
 293                         </varlistentry>
 294
 295                         <varlistentry>
 296                                 <term><varname>modules-load=</varname></term>
 297                                 <term><varname>rd.modules-load=</varname></term>
 298
 299                                 <listitem>
 300                                         <para>Load a specific kernel
 301                                         module early at boot. For
 302                                         details, see
 303                                         <citerefentry><refentrytitle>systemd-modules-load.service</refentrytitle><manvolnum>8</manvolnum></citerefentry>.</para>
 304                                 </listitem>
 305                         </varlistentry>
 306
 307                 </variablelist>
 308
 309         </refsect1>
 310
 311         <refsect1>
 312                   <title>See Also</title>
 313                   <para>
 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>
 328                   </para>
 329         </refsect1>
 330
 331 </refentry>