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='die-net'><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_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 the system and service
  95           manager to control system behavior. For details, see
  96           <citerefentry><refentrytitle>systemd</refentrytitle><manvolnum>1</manvolnum></citerefentry>.</para>
  97         </listitem>
  98       </varlistentry>
  99
 100       <varlistentry>
 101         <term><varname>systemd.mask=</varname></term>
 102         <term><varname>systemd.wants=</varname></term>
 103         <term><varname>systemd.debug-shell</varname></term>
 104         <listitem>
 105           <para>Additional parameters understood by
 106           <citerefentry><refentrytitle>systemd-debug-generator</refentrytitle><manvolnum>8</manvolnum></citerefentry>,
 107           to mask or start specific units at boot, or invoke a debug
 108           shell on tty9.</para>
 109         </listitem>
 110       </varlistentry>
 111
 112       <varlistentry>
 113         <term><varname>systemd.restore_state=</varname></term>
 114         <listitem>
 115           <para>This parameter is understood by several system tools
 116           to control whether or not they should restore system state
 117           from the previous boot. For details, see
 118           <citerefentry><refentrytitle>systemd-backlight@.service</refentrytitle><manvolnum>8</manvolnum></citerefentry>
 119           and
 120           <citerefentry><refentrytitle>systemd-rfkill@.service</refentrytitle><manvolnum>8</manvolnum></citerefentry>.
 121           </para>
 122         </listitem>
 123       </varlistentry>
 124
 125       <varlistentry>
 126         <term><varname>quiet</varname></term>
 127         <listitem>
 128           <para>Parameter understood by both the kernel and the system
 129           and service manager to control console log verbosity. For
 130           details, see
 131           <citerefentry><refentrytitle>systemd</refentrytitle><manvolnum>1</manvolnum></citerefentry>.</para>
 132         </listitem>
 133       </varlistentry>
 134
 135       <varlistentry>
 136         <term><varname>debug</varname></term>
 137         <listitem>
 138           <para>Parameter understood by both the kernel and the system
 139           and service manager to control console log verbosity. For
 140           details, see
 141           <citerefentry><refentrytitle>systemd</refentrytitle><manvolnum>1</manvolnum></citerefentry>.</para>
 142         </listitem>
 143       </varlistentry>
 144
 145       <varlistentry>
 146         <term><varname>-b</varname></term>
 147         <term><varname>emergency</varname></term>
 148         <term><varname>rescue</varname></term>
 149         <term><varname>single</varname></term>
 150         <term><varname>s</varname></term>
 151         <term><varname>S</varname></term>
 152         <term><varname>1</varname></term>
 153         <term><varname>2</varname></term>
 154         <term><varname>3</varname></term>
 155         <term><varname>4</varname></term>
 156         <term><varname>5</varname></term>
 157         <listitem>
 158           <para>Parameters understood by the system and service
 159           manager, as compatibility options. For details, see
 160           <citerefentry><refentrytitle>systemd</refentrytitle><manvolnum>1</manvolnum></citerefentry>.</para>
 161         </listitem>
 162       </varlistentry>
 163
 164       <varlistentry>
 165         <term><varname>locale.LANG=</varname></term>
 166         <term><varname>locale.LANGUAGE=</varname></term>
 167         <term><varname>locale.LC_CTYPE=</varname></term>
 168         <term><varname>locale.LC_NUMERIC=</varname></term>
 169         <term><varname>locale.LC_TIME=</varname></term>
 170         <term><varname>locale.LC_COLLATE=</varname></term>
 171         <term><varname>locale.LC_MONETARY=</varname></term>
 172         <term><varname>locale.LC_MESSAGES=</varname></term>
 173         <term><varname>locale.LC_PAPER=</varname></term>
 174         <term><varname>locale.LC_NAME=</varname></term>
 175         <term><varname>locale.LC_ADDRESS=</varname></term>
 176         <term><varname>locale.LC_TELEPHONE=</varname></term>
 177         <term><varname>locale.LC_MEASUREMENT=</varname></term>
 178         <term><varname>locale.LC_IDENTIFICATION=</varname></term>
 179         <listitem>
 180           <para>Parameters understood by the system and service
 181           manager to control locale and language settings. For
 182           details, see
 183           <citerefentry><refentrytitle>systemd</refentrytitle><manvolnum>1</manvolnum></citerefentry>.</para>
 184         </listitem>
 185       </varlistentry>
 186
 187       <varlistentry>
 188         <term><varname>fsck.mode=</varname></term>
 189         <term><varname>fsck.repair=</varname></term>
 190
 191         <listitem>
 192           <para>Parameters understood by the file system checker
 193           services. For details, see
 194           <citerefentry><refentrytitle>systemd-fsck@.service</refentrytitle><manvolnum>8</manvolnum></citerefentry>.</para>
 195         </listitem>
 196       </varlistentry>
 197
 198       <varlistentry>
 199         <term><varname>quotacheck.mode=</varname></term>
 200
 201         <listitem>
 202           <para>Parameter understood by the file quota checker
 203           service. For details, see
 204           <citerefentry><refentrytitle>systemd-quotacheck.service</refentrytitle><manvolnum>8</manvolnum></citerefentry>.</para>
 205         </listitem>
 206       </varlistentry>
 207
 208       <varlistentry>
 209         <term><varname>systemd.journald.forward_to_syslog=</varname></term>
 210         <term><varname>systemd.journald.forward_to_kmsg=</varname></term>
 211         <term><varname>systemd.journald.forward_to_console=</varname></term>
 212         <term><varname>systemd.journald.forward_to_wall=</varname></term>
 213
 214         <listitem>
 215           <para>Parameters understood by the journal service. For
 216           details, see
 217           <citerefentry><refentrytitle>systemd-journald.service</refentrytitle><manvolnum>8</manvolnum></citerefentry>.</para>
 218         </listitem>
 219       </varlistentry>
 220
 221       <varlistentry>
 222         <term><varname>vconsole.keymap=</varname></term>
 223         <term><varname>vconsole.keymap.toggle=</varname></term>
 224         <term><varname>vconsole.font=</varname></term>
 225         <term><varname>vconsole.font.map=</varname></term>
 226         <term><varname>vconsole.font.unimap=</varname></term>
 227
 228         <listitem>
 229           <para>Parameters understood by the virtual console setup
 230           logic. For 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>udev.event-timeout=</varname></term>
 243         <term><varname>rd.udev.event-timeout=</varname></term>
 244         <term><varname>net.ifnames=</varname></term>
 245
 246         <listitem>
 247           <para>Parameters understood by the device event managing
 248           daemon. For details, see
 249           <citerefentry><refentrytitle>systemd-udevd.service</refentrytitle><manvolnum>8</manvolnum></citerefentry>.</para>
 250         </listitem>
 251       </varlistentry>
 252
 253       <varlistentry>
 254         <term><varname>plymouth.enable=</varname></term>
 255
 256         <listitem>
 257           <para>May be used to disable the Plymouth boot splash. For
 258           details, see
 259           <citerefentry project='die-net'><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.name=</varname></term>
 269         <term><varname>rd.luks.name=</varname></term>
 270         <term><varname>luks.uuid=</varname></term>
 271         <term><varname>rd.luks.uuid=</varname></term>
 272         <term><varname>luks.options=</varname></term>
 273         <term><varname>rd.luks.options=</varname></term>
 274         <term><varname>luks.key=</varname></term>
 275         <term><varname>rd.luks.key=</varname></term>
 276
 277         <listitem>
 278           <para>Configures the LUKS full-disk encryption logic at
 279           boot. For details, see
 280           <citerefentry><refentrytitle>systemd-cryptsetup-generator</refentrytitle><manvolnum>8</manvolnum></citerefentry>.</para>
 281         </listitem>
 282       </varlistentry>
 283
 284       <varlistentry>
 285         <term><varname>fstab=</varname></term>
 286         <term><varname>rd.fstab=</varname></term>
 287
 288         <listitem>
 289           <para>Configures the <filename>/etc/fstab</filename> logic
 290           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>root=</varname></term>
 297         <term><varname>rootfstype=</varname></term>
 298         <term><varname>rootfsflags=</varname></term>
 299         <term><varname>ro</varname></term>
 300         <term><varname>rw</varname></term>
 301
 302         <listitem>
 303           <para>Configures the root file system and its file system
 304           type and mount options, as well as whether it shall be
 305           mounted read-only or read-writable initially. For details,
 306           see
 307           <citerefentry><refentrytitle>systemd-fstab-generator</refentrytitle><manvolnum>8</manvolnum></citerefentry>.</para>
 308         </listitem>
 309       </varlistentry>
 310
 311       <varlistentry>
 312         <term><varname>systemd.gpt_auto=</varname></term>
 313         <term><varname>rd.systemd.gpt_auto=</varname></term>
 314
 315         <listitem>
 316           <para>Configures whether GPT based partition auto-discovery
 317           shall be attempted. For details, see
 318           <citerefentry><refentrytitle>systemd-gpt-auto-generator</refentrytitle><manvolnum>8</manvolnum></citerefentry>.</para>
 319         </listitem>
 320       </varlistentry>
 321
 322       <varlistentry>
 323         <term><varname>modules-load=</varname></term>
 324         <term><varname>rd.modules-load=</varname></term>
 325
 326         <listitem>
 327           <para>Load a specific kernel module early at boot. For
 328           details, see
 329           <citerefentry><refentrytitle>systemd-modules-load.service</refentrytitle><manvolnum>8</manvolnum></citerefentry>.</para>
 330         </listitem>
 331       </varlistentry>
 332
 333       <varlistentry>
 334         <term><varname>resume=</varname></term>
 335
 336         <listitem>
 337           <para>Enables resume from hibernation using the specified
 338           device. All
 339           <citerefentry><refentrytitle>fstab</refentrytitle><manvolnum>5</manvolnum></citerefentry>-like
 340           paths are supported. For details, see
 341           <citerefentry><refentrytitle>systemd-hibernate-resume-generator</refentrytitle><manvolnum>8</manvolnum></citerefentry>.</para>
 342         </listitem>
 343       </varlistentry>
 344     </variablelist>
 345
 346   </refsect1>
 347
 348   <refsect1>
 349       <title>See Also</title>
 350       <para>
 351         <citerefentry><refentrytitle>systemd</refentrytitle><manvolnum>1</manvolnum></citerefentry>,
 352         <citerefentry project='man-pages'><refentrytitle>bootparam</refentrytitle><manvolnum>7</manvolnum></citerefentry>,
 353         <citerefentry project='die-net'><refentrytitle>dracut.cmdline</refentrytitle><manvolnum>7</manvolnum></citerefentry>,
 354         <citerefentry><refentrytitle>systemd-debug-generator</refentrytitle><manvolnum>8</manvolnum></citerefentry>,
 355         <citerefentry><refentrytitle>systemd-fsck@.service</refentrytitle><manvolnum>8</manvolnum></citerefentry>,
 356         <citerefentry><refentrytitle>systemd-quotacheck.service</refentrytitle><manvolnum>8</manvolnum></citerefentry>,
 357         <citerefentry><refentrytitle>systemd-journald.service</refentrytitle><manvolnum>8</manvolnum></citerefentry>,
 358         <citerefentry><refentrytitle>systemd-vconsole-setup.service</refentrytitle><manvolnum>8</manvolnum></citerefentry>,
 359         <citerefentry><refentrytitle>systemd-udevd.service</refentrytitle><manvolnum>8</manvolnum></citerefentry>,
 360         <citerefentry project='die-net'><refentrytitle>plymouth</refentrytitle><manvolnum>8</manvolnum></citerefentry>,
 361         <citerefentry><refentrytitle>systemd-cryptsetup-generator</refentrytitle><manvolnum>8</manvolnum></citerefentry>,
 362         <citerefentry><refentrytitle>systemd-fstab-generator</refentrytitle><manvolnum>8</manvolnum></citerefentry>,
 363         <citerefentry><refentrytitle>systemd-gpt-auto-generator</refentrytitle><manvolnum>8</manvolnum></citerefentry>,
 364         <citerefentry><refentrytitle>systemd-modules-load.service</refentrytitle><manvolnum>8</manvolnum></citerefentry>,
 365         <citerefentry><refentrytitle>systemd-backlight@.service</refentrytitle><manvolnum>8</manvolnum></citerefentry>,
 366         <citerefentry><refentrytitle>systemd-rfkill@.service</refentrytitle><manvolnum>8</manvolnum></citerefentry>,
 367         <citerefentry><refentrytitle>systemd-hibernate-resume-generator</refentrytitle><manvolnum>8</manvolnum></citerefentry>
 368       </para>
 369   </refsect1>
 370
 371 </refentry>