man/kernel-command-line.html

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  22   <a href="../libudev/index.html">gudev </a><span style="float:right">systemd 220</span><hr><div class="refentry"><a name="kernel-command-line"></a><div class="titlepage"></div><div class="refnamediv"><h2>Name</h2><p>kernel-command-line — Kernel command line parameters</p></div><div class="refsynopsisdiv"><h2>Synopsis</h2><p><code class="filename">/proc/cmdline</code></p></div><div class="refsect1"><a name="idm140603967621936"></a><h2 id="Description">Description<a class="headerlink" title="Permalink to this headline" href="#Description">¶</a></h2><p>The kernel, the initial RAM disk (initrd) and
  23     basic userspace functionality may be configured at boot via
  24     kernel command line arguments.</p><p>For command line parameters understood by the kernel, please
  25     see <a class="ulink" href="https://www.kernel.org/doc/Documentation/kernel-parameters.txt" target="_top"><code class="filename">kernel-parameters.txt</code></a>
  26     and
  27     <a href="http://man7.org/linux/man-pages/man7/bootparam.7.html"><span class="citerefentry"><span class="refentrytitle">bootparam</span>(7)</span></a>.</p><p>For command line parameters understood by the initial RAM
  28     disk, please see
  29     <a href="http://linux.die.net/man/7/dracut.cmdline"><span class="citerefentry"><span class="refentrytitle">dracut.cmdline</span>(7)</span></a>,
  30     or the documentation of the specific initrd implementation of your
  31     installation.</p></div><div class="refsect1"><a name="idm140603962663808"></a><h2 id="Core OS Command Line Arguments">Core OS Command Line Arguments<a class="headerlink" title="Permalink to this headline" href="#Core%20OS%20Command%20Line%20Arguments">¶</a></h2><div class="variablelist"><dl class="variablelist"><dt id="systemd.unit="><span class="term"><code class="varname">systemd.unit=</code>, </span><span class="term"><code class="varname">rd.systemd.unit=</code>, </span><span class="term"><code class="varname">systemd.dump_core=</code>, </span><span class="term"><code class="varname">systemd.crash_shell=</code>, </span><span class="term"><code class="varname">systemd.crash_chvt=</code>, </span><span class="term"><code class="varname">systemd.confirm_spawn=</code>, </span><span class="term"><code class="varname">systemd.show_status=</code>, </span><span class="term"><code class="varname">systemd.log_target=</code>, </span><span class="term"><code class="varname">systemd.log_level=</code>, </span><span class="term"><code class="varname">systemd.log_color=</code>, </span><span class="term"><code class="varname">systemd.log_location=</code>, </span><span class="term"><code class="varname">systemd.default_standard_output=</code>, </span><span class="term"><code class="varname">systemd.default_standard_error=</code>, </span><span class="term"><code class="varname">systemd.setenv=</code></span><a class="headerlink" title="Permalink to this term" href="#systemd.unit=">¶</a></dt><dd><p>Parameters understood by the system and service
  32           manager to control system behavior. For details, see
  33           <a href="systemd.html"><span class="citerefentry"><span class="refentrytitle">systemd</span>(1)</span></a>.</p></dd><dt id="systemd.mask="><span class="term"><code class="varname">systemd.mask=</code>, </span><span class="term"><code class="varname">systemd.wants=</code>, </span><span class="term"><code class="varname">systemd.debug-shell</code></span><a class="headerlink" title="Permalink to this term" href="#systemd.mask=">¶</a></dt><dd><p>Additional parameters understood by
  34           <a href="systemd-debug-generator.html"><span class="citerefentry"><span class="refentrytitle">systemd-debug-generator</span>(8)</span></a>,
  35           to mask or start specific units at boot, or invoke a debug
  36           shell on tty9.</p></dd><dt id="systemd.restore_state="><span class="term"><code class="varname">systemd.restore_state=</code></span><a class="headerlink" title="Permalink to this term" href="#systemd.restore_state=">¶</a></dt><dd><p>This parameter is understood by several system tools
  37           to control whether or not they should restore system state
  38           from the previous boot. For details, see
  39           <a href="systemd-backlight@.service.html"><span class="citerefentry"><span class="refentrytitle">systemd-backlight@.service</span>(8)</span></a>
  40           and
  41           <a href="systemd-rfkill@.service.html"><span class="citerefentry"><span class="refentrytitle">systemd-rfkill@.service</span>(8)</span></a>.
  42           </p></dd><dt id="quiet"><span class="term"><code class="varname">quiet</code></span><a class="headerlink" title="Permalink to this term" href="#quiet">¶</a></dt><dd><p>Parameter understood by both the kernel and the system
  43           and service manager to control console log verbosity. For
  44           details, see
  45           <a href="systemd.html"><span class="citerefentry"><span class="refentrytitle">systemd</span>(1)</span></a>.</p></dd><dt id="debug"><span class="term"><code class="varname">debug</code></span><a class="headerlink" title="Permalink to this term" href="#debug">¶</a></dt><dd><p>Parameter understood by both the kernel and the system
  46           and service manager to control console log verbosity. For
  47           details, see
  48           <a href="systemd.html"><span class="citerefentry"><span class="refentrytitle">systemd</span>(1)</span></a>.</p></dd><dt id="-b"><span class="term"><code class="varname">-b</code>, </span><span class="term"><code class="varname">emergency</code>, </span><span class="term"><code class="varname">rescue</code>, </span><span class="term"><code class="varname">single</code>, </span><span class="term"><code class="varname">s</code>, </span><span class="term"><code class="varname">S</code>, </span><span class="term"><code class="varname">1</code>, </span><span class="term"><code class="varname">2</code>, </span><span class="term"><code class="varname">3</code>, </span><span class="term"><code class="varname">4</code>, </span><span class="term"><code class="varname">5</code></span><a class="headerlink" title="Permalink to this term" href="#-b">¶</a></dt><dd><p>Parameters understood by the system and service
  49           manager, as compatibility options. For details, see
  50           <a href="systemd.html"><span class="citerefentry"><span class="refentrytitle">systemd</span>(1)</span></a>.</p></dd><dt id="locale.LANG="><span class="term"><code class="varname">locale.LANG=</code>, </span><span class="term"><code class="varname">locale.LANGUAGE=</code>, </span><span class="term"><code class="varname">locale.LC_CTYPE=</code>, </span><span class="term"><code class="varname">locale.LC_NUMERIC=</code>, </span><span class="term"><code class="varname">locale.LC_TIME=</code>, </span><span class="term"><code class="varname">locale.LC_COLLATE=</code>, </span><span class="term"><code class="varname">locale.LC_MONETARY=</code>, </span><span class="term"><code class="varname">locale.LC_MESSAGES=</code>, </span><span class="term"><code class="varname">locale.LC_PAPER=</code>, </span><span class="term"><code class="varname">locale.LC_NAME=</code>, </span><span class="term"><code class="varname">locale.LC_ADDRESS=</code>, </span><span class="term"><code class="varname">locale.LC_TELEPHONE=</code>, </span><span class="term"><code class="varname">locale.LC_MEASUREMENT=</code>, </span><span class="term"><code class="varname">locale.LC_IDENTIFICATION=</code></span><a class="headerlink" title="Permalink to this term" href="#locale.LANG=">¶</a></dt><dd><p>Parameters understood by the system and service
  51           manager to control locale and language settings. For
  52           details, see
  53           <a href="systemd.html"><span class="citerefentry"><span class="refentrytitle">systemd</span>(1)</span></a>.</p></dd><dt id="fsck.mode="><span class="term"><code class="varname">fsck.mode=</code>, </span><span class="term"><code class="varname">fsck.repair=</code></span><a class="headerlink" title="Permalink to this term" href="#fsck.mode=">¶</a></dt><dd><p>Parameters understood by the file system checker
  54           services. For details, see
  55           <a href="systemd-fsck@.service.html"><span class="citerefentry"><span class="refentrytitle">systemd-fsck@.service</span>(8)</span></a>.</p></dd><dt id="quotacheck.mode="><span class="term"><code class="varname">quotacheck.mode=</code></span><a class="headerlink" title="Permalink to this term" href="#quotacheck.mode=">¶</a></dt><dd><p>Parameter understood by the file quota checker
  56           service. For details, see
  57           <a href="systemd-quotacheck.service.html"><span class="citerefentry"><span class="refentrytitle">systemd-quotacheck.service</span>(8)</span></a>.</p></dd><dt id="systemd.journald.forward_to_syslog="><span class="term"><code class="varname">systemd.journald.forward_to_syslog=</code>, </span><span class="term"><code class="varname">systemd.journald.forward_to_kmsg=</code>, </span><span class="term"><code class="varname">systemd.journald.forward_to_console=</code>, </span><span class="term"><code class="varname">systemd.journald.forward_to_wall=</code></span><a class="headerlink" title="Permalink to this term" href="#systemd.journald.forward_to_syslog=">¶</a></dt><dd><p>Parameters understood by the journal service. For
  58           details, see
  59           <a href="systemd-journald.service.html"><span class="citerefentry"><span class="refentrytitle">systemd-journald.service</span>(8)</span></a>.</p></dd><dt id="vconsole.keymap="><span class="term"><code class="varname">vconsole.keymap=</code>, </span><span class="term"><code class="varname">vconsole.keymap.toggle=</code>, </span><span class="term"><code class="varname">vconsole.font=</code>, </span><span class="term"><code class="varname">vconsole.font.map=</code>, </span><span class="term"><code class="varname">vconsole.font.unimap=</code></span><a class="headerlink" title="Permalink to this term" href="#vconsole.keymap=">¶</a></dt><dd><p>Parameters understood by the virtual console setup
  60           logic. For details, see
  61           <a href="systemd-vconsole-setup.service.html"><span class="citerefentry"><span class="refentrytitle">systemd-vconsole-setup.service</span>(8)</span></a>.</p></dd><dt id="udev.log-priority="><span class="term"><code class="varname">udev.log-priority=</code>, </span><span class="term"><code class="varname">rd.udev.log-priority=</code>, </span><span class="term"><code class="varname">udev.children-max=</code>, </span><span class="term"><code class="varname">rd.udev.children-max=</code>, </span><span class="term"><code class="varname">udev.exec-delay=</code>, </span><span class="term"><code class="varname">rd.udev.exec-delay=</code>, </span><span class="term"><code class="varname">udev.event-timeout=</code>, </span><span class="term"><code class="varname">rd.udev.event-timeout=</code>, </span><span class="term"><code class="varname">net.ifnames=</code></span><a class="headerlink" title="Permalink to this term" href="#udev.log-priority=">¶</a></dt><dd><p>Parameters understood by the device event managing
  62           daemon. For details, see
  63           <a href="systemd-udevd.service.html"><span class="citerefentry"><span class="refentrytitle">systemd-udevd.service</span>(8)</span></a>.</p></dd><dt id="plymouth.enable="><span class="term"><code class="varname">plymouth.enable=</code></span><a class="headerlink" title="Permalink to this term" href="#plymouth.enable=">¶</a></dt><dd><p>May be used to disable the Plymouth boot splash. For
  64           details, see
  65           <a href="http://linux.die.net/man/8/plymouth"><span class="citerefentry"><span class="refentrytitle">plymouth</span>(8)</span></a>.</p></dd><dt id="luks="><span class="term"><code class="varname">luks=</code>, </span><span class="term"><code class="varname">rd.luks=</code>, </span><span class="term"><code class="varname">luks.crypttab=</code>, </span><span class="term"><code class="varname">rd.luks.crypttab=</code>, </span><span class="term"><code class="varname">luks.name=</code>, </span><span class="term"><code class="varname">rd.luks.name=</code>, </span><span class="term"><code class="varname">luks.uuid=</code>, </span><span class="term"><code class="varname">rd.luks.uuid=</code>, </span><span class="term"><code class="varname">luks.options=</code>, </span><span class="term"><code class="varname">rd.luks.options=</code>, </span><span class="term"><code class="varname">luks.key=</code>, </span><span class="term"><code class="varname">rd.luks.key=</code></span><a class="headerlink" title="Permalink to this term" href="#luks=">¶</a></dt><dd><p>Configures the LUKS full-disk encryption logic at
  66           boot. For details, see
  67           <a href="systemd-cryptsetup-generator.html"><span class="citerefentry"><span class="refentrytitle">systemd-cryptsetup-generator</span>(8)</span></a>.</p></dd><dt id="fstab="><span class="term"><code class="varname">fstab=</code>, </span><span class="term"><code class="varname">rd.fstab=</code></span><a class="headerlink" title="Permalink to this term" href="#fstab=">¶</a></dt><dd><p>Configures the <code class="filename">/etc/fstab</code> logic
  68           at boot. For details, see
  69           <a href="systemd-fstab-generator.html"><span class="citerefentry"><span class="refentrytitle">systemd-fstab-generator</span>(8)</span></a>.</p></dd><dt id="root="><span class="term"><code class="varname">root=</code>, </span><span class="term"><code class="varname">rootfstype=</code>, </span><span class="term"><code class="varname">rootflags=</code>, </span><span class="term"><code class="varname">ro</code>, </span><span class="term"><code class="varname">rw</code></span><a class="headerlink" title="Permalink to this term" href="#root=">¶</a></dt><dd><p>Configures the root file system and its file system
  70           type and mount options, as well as whether it shall be
  71           mounted read-only or read-writable initially. For details,
  72           see
  73           <a href="systemd-fstab-generator.html"><span class="citerefentry"><span class="refentrytitle">systemd-fstab-generator</span>(8)</span></a>.</p></dd><dt id="systemd.gpt_auto="><span class="term"><code class="varname">systemd.gpt_auto=</code>, </span><span class="term"><code class="varname">rd.systemd.gpt_auto=</code></span><a class="headerlink" title="Permalink to this term" href="#systemd.gpt_auto=">¶</a></dt><dd><p>Configures whether GPT based partition auto-discovery
  74           shall be attempted. For details, see
  75           <a href="systemd-gpt-auto-generator.html"><span class="citerefentry"><span class="refentrytitle">systemd-gpt-auto-generator</span>(8)</span></a>.</p></dd><dt id="modules-load="><span class="term"><code class="varname">modules-load=</code>, </span><span class="term"><code class="varname">rd.modules-load=</code></span><a class="headerlink" title="Permalink to this term" href="#modules-load=">¶</a></dt><dd><p>Load a specific kernel module early at boot. For
  76           details, see
  77           <a href="systemd-modules-load.service.html"><span class="citerefentry"><span class="refentrytitle">systemd-modules-load.service</span>(8)</span></a>.</p></dd><dt id="resume="><span class="term"><code class="varname">resume=</code></span><a class="headerlink" title="Permalink to this term" href="#resume=">¶</a></dt><dd><p>Enables resume from hibernation using the specified
  78           device. All
  79           <a href="http://man7.org/linux/man-pages/man5/fstab.5.html"><span class="citerefentry"><span class="refentrytitle">fstab</span>(5)</span></a>-like
  80           paths are supported. For details, see
  81           <a href="systemd-hibernate-resume-generator.html"><span class="citerefentry"><span class="refentrytitle">systemd-hibernate-resume-generator</span>(8)</span></a>.</p></dd></dl></div></div><div class="refsect1"><a name="idm140603962574400"></a><h2 id="See Also">See Also<a class="headerlink" title="Permalink to this headline" href="#See%20Also">¶</a></h2><p>
  82         <a href="systemd.html"><span class="citerefentry"><span class="refentrytitle">systemd</span>(1)</span></a>,
  83         <a href="http://man7.org/linux/man-pages/man7/bootparam.7.html"><span class="citerefentry"><span class="refentrytitle">bootparam</span>(7)</span></a>,
  84         <a href="http://linux.die.net/man/7/dracut.cmdline"><span class="citerefentry"><span class="refentrytitle">dracut.cmdline</span>(7)</span></a>,
  85         <a href="systemd-debug-generator.html"><span class="citerefentry"><span class="refentrytitle">systemd-debug-generator</span>(8)</span></a>,
  86         <a href="systemd-fsck@.service.html"><span class="citerefentry"><span class="refentrytitle">systemd-fsck@.service</span>(8)</span></a>,
  87         <a href="systemd-quotacheck.service.html"><span class="citerefentry"><span class="refentrytitle">systemd-quotacheck.service</span>(8)</span></a>,
  88         <a href="systemd-journald.service.html"><span class="citerefentry"><span class="refentrytitle">systemd-journald.service</span>(8)</span></a>,
  89         <a href="systemd-vconsole-setup.service.html"><span class="citerefentry"><span class="refentrytitle">systemd-vconsole-setup.service</span>(8)</span></a>,
  90         <a href="systemd-udevd.service.html"><span class="citerefentry"><span class="refentrytitle">systemd-udevd.service</span>(8)</span></a>,
  91         <a href="http://linux.die.net/man/8/plymouth"><span class="citerefentry"><span class="refentrytitle">plymouth</span>(8)</span></a>,
  92         <a href="systemd-cryptsetup-generator.html"><span class="citerefentry"><span class="refentrytitle">systemd-cryptsetup-generator</span>(8)</span></a>,
  93         <a href="systemd-fstab-generator.html"><span class="citerefentry"><span class="refentrytitle">systemd-fstab-generator</span>(8)</span></a>,
  94         <a href="systemd-gpt-auto-generator.html"><span class="citerefentry"><span class="refentrytitle">systemd-gpt-auto-generator</span>(8)</span></a>,
  95         <a href="systemd-modules-load.service.html"><span class="citerefentry"><span class="refentrytitle">systemd-modules-load.service</span>(8)</span></a>,
  96         <a href="systemd-backlight@.service.html"><span class="citerefentry"><span class="refentrytitle">systemd-backlight@.service</span>(8)</span></a>,
  97         <a href="systemd-rfkill@.service.html"><span class="citerefentry"><span class="refentrytitle">systemd-rfkill@.service</span>(8)</span></a>,
  98         <a href="systemd-hibernate-resume-generator.html"><span class="citerefentry"><span class="refentrytitle">systemd-hibernate-resume-generator</span>(8)</span></a>
  99       </p></div></div></body></html>