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6741N/A

6741N/A<refentry id="kernel-command-line">

6741N/A

6741N/A <refentryinfo>

6741N/A <title>kernel-command-line</title>

6741N/A <productname>systemd</productname>

6741N/A

6741N/A <authorgroup>

6741N/A <author>

6741N/A <contrib>Developer</contrib>

6741N/A <firstname>Lennart</firstname>

6741N/A <surname>Poettering</surname>

6741N/A <email>lennart@poettering.net</email>

6741N/A </author>

6741N/A </authorgroup>

6741N/A </refentryinfo>

6741N/A

6741N/A <refmeta>

6741N/A <refentrytitle>kernel-command-line</refentrytitle>

6741N/A <manvolnum>7</manvolnum>

6741N/A </refmeta>

6741N/A

6741N/A <refnamediv>

6741N/A <refname>kernel-command-line</refname>

6741N/A <refpurpose>Kernel command line parameters</refpurpose>

6741N/A </refnamediv>

6741N/A

6741N/A <refsynopsisdiv>

6741N/A <para><filename>/proc/cmdline</filename></para>

6741N/A </refsynopsisdiv>

6741N/A

6741N/A <refsect1>

<title>Description</title>

<para>The kernel, the initial RAM disk (initrd) and

basic userspace functionality may be configured at boot via

kernel command line arguments.</para>

<para>For command line parameters understood by the kernel, please

see <ulink

url="https://www.kernel.org/doc/Documentation/kernel-parameters.txt"><filename>kernel-parameters.txt</filename></ulink>

and

<citerefentry project='man-pages'><refentrytitle>bootparam</refentrytitle><manvolnum>7</manvolnum></citerefentry>.</para>

<para>For command line parameters understood by the initial RAM

disk, please see

<citerefentry project='die-net'><refentrytitle>dracut.cmdline</refentrytitle><manvolnum>7</manvolnum></citerefentry>,

or the documentation of the specific initrd implementation of your

installation.</para>

</refsect1>

<refsect1>

<title>Core OS Command Line Arguments</title>

<variablelist class='kernel-commandline-options'>

<varlistentry>

<term><varname>systemd.unit=</varname></term>

<term><varname>rd.systemd.unit=</varname></term>

<term><varname>systemd.dump_core=</varname></term>

<term><varname>systemd.crash_shell=</varname></term>

<term><varname>systemd.crash_chvt=</varname></term>

<term><varname>systemd.confirm_spawn=</varname></term>

<term><varname>systemd.show_status=</varname></term>

<term><varname>systemd.log_target=</varname></term>

<term><varname>systemd.log_level=</varname></term>

<term><varname>systemd.log_color=</varname></term>

<term><varname>systemd.log_location=</varname></term>

<term><varname>systemd.default_standard_output=</varname></term>

<term><varname>systemd.default_standard_error=</varname></term>

<term><varname>systemd.setenv=</varname></term>

<listitem>

<para>Parameters understood by the system and service

manager to control system behavior. For details, see

<citerefentry><refentrytitle>systemd</refentrytitle><manvolnum>1</manvolnum></citerefentry>.</para>

</listitem>

</varlistentry>

<varlistentry>

<term><varname>systemd.mask=</varname></term>

<term><varname>systemd.wants=</varname></term>

<term><varname>systemd.debug-shell</varname></term>

<listitem>

<para>Additional parameters understood by

<citerefentry><refentrytitle>systemd-debug-generator</refentrytitle><manvolnum>8</manvolnum></citerefentry>,

to mask or start specific units at boot, or invoke a debug

shell on tty9.</para>

</listitem>

</varlistentry>

<varlistentry>

<term><varname>systemd.restore_state=</varname></term>

<listitem>

<para>This parameter is understood by several system tools

to control whether or not they should restore system state

from the previous boot. For details, see

<citerefentry><refentrytitle>systemd-backlight@.service</refentrytitle><manvolnum>8</manvolnum></citerefentry>

and

<citerefentry><refentrytitle>systemd-rfkill@.service</refentrytitle><manvolnum>8</manvolnum></citerefentry>.

</para>

</listitem>

</varlistentry>

<varlistentry>

<term><varname>quiet</varname></term>

<listitem>

<para>Parameter understood by both the kernel and the system

and service manager to control console log verbosity. For

details, see

<citerefentry><refentrytitle>systemd</refentrytitle><manvolnum>1</manvolnum></citerefentry>.</para>

</listitem>

</varlistentry>

<varlistentry>

<term><varname>debug</varname></term>

<listitem>

<para>Parameter understood by both the kernel and the system

and service manager to control console log verbosity. For

details, see

<citerefentry><refentrytitle>systemd</refentrytitle><manvolnum>1</manvolnum></citerefentry>.</para>

</listitem>

</varlistentry>

<varlistentry>

<term><varname>-b</varname></term>

<term><varname>emergency</varname></term>

<term><varname>rescue</varname></term>

<term><varname>single</varname></term>

<term><varname>s</varname></term>

<term><varname>S</varname></term>

<term><varname>1</varname></term>

<term><varname>2</varname></term>

<term><varname>3</varname></term>

<term><varname>4</varname></term>

<term><varname>5</varname></term>

<listitem>

<para>Parameters understood by the system and service

manager, as compatibility options. For details, see

<citerefentry><refentrytitle>systemd</refentrytitle><manvolnum>1</manvolnum></citerefentry>.</para>

</listitem>

</varlistentry>

<varlistentry>

<term><varname>locale.LANG=</varname></term>

<term><varname>locale.LANGUAGE=</varname></term>

<term><varname>locale.LC_CTYPE=</varname></term>

<term><varname>locale.LC_NUMERIC=</varname></term>

<term><varname>locale.LC_TIME=</varname></term>

<term><varname>locale.LC_COLLATE=</varname></term>

<term><varname>locale.LC_MONETARY=</varname></term>

<term><varname>locale.LC_MESSAGES=</varname></term>

<term><varname>locale.LC_PAPER=</varname></term>

<term><varname>locale.LC_NAME=</varname></term>

<term><varname>locale.LC_ADDRESS=</varname></term>

<term><varname>locale.LC_TELEPHONE=</varname></term>

<term><varname>locale.LC_MEASUREMENT=</varname></term>

<term><varname>locale.LC_IDENTIFICATION=</varname></term>

<listitem>

<para>Parameters understood by the system and service

manager to control locale and language settings. For

details, see

<citerefentry><refentrytitle>systemd</refentrytitle><manvolnum>1</manvolnum></citerefentry>.</para>

</listitem>

</varlistentry>

<varlistentry>

<term><varname>fsck.mode=</varname></term>

<term><varname>fsck.repair=</varname></term>

<listitem>

<para>Parameters understood by the file system checker

services. For details, see

<citerefentry><refentrytitle>systemd-fsck@.service</refentrytitle><manvolnum>8</manvolnum></citerefentry>.</para>

</listitem>

</varlistentry>

<varlistentry>

<term><varname>quotacheck.mode=</varname></term>

<listitem>

<para>Parameter understood by the file quota checker

service. For details, see

<citerefentry><refentrytitle>systemd-quotacheck.service</refentrytitle><manvolnum>8</manvolnum></citerefentry>.</para>

</listitem>

</varlistentry>

<varlistentry>

<term><varname>systemd.journald.forward_to_syslog=</varname></term>

<term><varname>systemd.journald.forward_to_kmsg=</varname></term>

<term><varname>systemd.journald.forward_to_console=</varname></term>

<term><varname>systemd.journald.forward_to_wall=</varname></term>

<listitem>

<para>Parameters understood by the journal service. For

details, see

<citerefentry><refentrytitle>systemd-journald.service</refentrytitle><manvolnum>8</manvolnum></citerefentry>.</para>

</listitem>

</varlistentry>

<varlistentry>

<term><varname>vconsole.keymap=</varname></term>

<term><varname>vconsole.keymap.toggle=</varname></term>

<term><varname>vconsole.font=</varname></term>

<term><varname>vconsole.font.map=</varname></term>

<term><varname>vconsole.font.unimap=</varname></term>

<listitem>

<para>Parameters understood by the virtual console setup

logic. For details, see

<citerefentry><refentrytitle>systemd-vconsole-setup.service</refentrytitle><manvolnum>8</manvolnum></citerefentry>.</para>

</listitem>

</varlistentry>

<varlistentry>

<term><varname>udev.log-priority=</varname></term>

<term><varname>rd.udev.log-priority=</varname></term>

<term><varname>udev.children-max=</varname></term>

<term><varname>rd.udev.children-max=</varname></term>

<term><varname>udev.exec-delay=</varname></term>

<term><varname>rd.udev.exec-delay=</varname></term>

<term><varname>udev.event-timeout=</varname></term>

<term><varname>rd.udev.event-timeout=</varname></term>

<term><varname>net.ifnames=</varname></term>

<listitem>

<para>Parameters understood by the device event managing

daemon. For details, see

<citerefentry><refentrytitle>systemd-udevd.service</refentrytitle><manvolnum>8</manvolnum></citerefentry>.</para>

</listitem>

</varlistentry>

<varlistentry>

<term><varname>plymouth.enable=</varname></term>

<listitem>

<para>May be used to disable the Plymouth boot splash. For

details, see

<citerefentry project='die-net'><refentrytitle>plymouth</refentrytitle><manvolnum>8</manvolnum></citerefentry>.</para>

</listitem>

</varlistentry>

<varlistentry>

<term><varname>luks=</varname></term>

<term><varname>rd.luks=</varname></term>

<term><varname>luks.crypttab=</varname></term>

<term><varname>rd.luks.crypttab=</varname></term>

<term><varname>luks.name=</varname></term>

<term><varname>rd.luks.name=</varname></term>

<term><varname>luks.uuid=</varname></term>

<term><varname>rd.luks.uuid=</varname></term>

<term><varname>luks.options=</varname></term>

<term><varname>rd.luks.options=</varname></term>

<term><varname>luks.key=</varname></term>

<term><varname>rd.luks.key=</varname></term>

<listitem>

<para>Configures the LUKS full-disk encryption logic at

boot. For details, see

<citerefentry><refentrytitle>systemd-cryptsetup-generator</refentrytitle><manvolnum>8</manvolnum></citerefentry>.</para>

</listitem>

</varlistentry>

<varlistentry>

<term><varname>fstab=</varname></term>

<term><varname>rd.fstab=</varname></term>

<listitem>

<para>Configures the <filename>/etc/fstab</filename> logic

at boot. For details, see

<citerefentry><refentrytitle>systemd-fstab-generator</refentrytitle><manvolnum>8</manvolnum></citerefentry>.</para>

</listitem>

</varlistentry>

<varlistentry>

<term><varname>root=</varname></term>

<term><varname>rootfstype=</varname></term>

<term><varname>rootflags=</varname></term>

<term><varname>ro</varname></term>

<term><varname>rw</varname></term>

<listitem>

<para>Configures the root file system and its file system

type and mount options, as well as whether it shall be

mounted read-only or read-writable initially. For details,

see

<citerefentry><refentrytitle>systemd-fstab-generator</refentrytitle><manvolnum>8</manvolnum></citerefentry>.</para>

</listitem>

</varlistentry>

<varlistentry>

<term><varname>systemd.gpt_auto=</varname></term>

<term><varname>rd.systemd.gpt_auto=</varname></term>

<listitem>

<para>Configures whether GPT based partition auto-discovery

shall be attempted. For details, see

<citerefentry><refentrytitle>systemd-gpt-auto-generator</refentrytitle><manvolnum>8</manvolnum></citerefentry>.</para>

</listitem>

</varlistentry>

<varlistentry>

<term><varname>modules-load=</varname></term>

<term><varname>rd.modules-load=</varname></term>

<listitem>

<para>Load a specific kernel module early at boot. For

details, see

<citerefentry><refentrytitle>systemd-modules-load.service</refentrytitle><manvolnum>8</manvolnum></citerefentry>.</para>

</listitem>

</varlistentry>

<varlistentry>

<term><varname>resume=</varname></term>

<listitem>

<para>Enables resume from hibernation using the specified

device. All

<citerefentry project='man-pages'><refentrytitle>fstab</refentrytitle><manvolnum>5</manvolnum></citerefentry>-like

paths are supported. For details, see

<citerefentry><refentrytitle>systemd-hibernate-resume-generator</refentrytitle><manvolnum>8</manvolnum></citerefentry>.</para>

</listitem>

</varlistentry>

</variablelist>

</refsect1>

<refsect1>

<title>See Also</title>

<para>

<citerefentry><refentrytitle>systemd</refentrytitle><manvolnum>1</manvolnum></citerefentry>,

<citerefentry project='man-pages'><refentrytitle>bootparam</refentrytitle><manvolnum>7</manvolnum></citerefentry>,

<citerefentry project='die-net'><refentrytitle>dracut.cmdline</refentrytitle><manvolnum>7</manvolnum></citerefentry>,

<citerefentry><refentrytitle>systemd-debug-generator</refentrytitle><manvolnum>8</manvolnum></citerefentry>,

<citerefentry><refentrytitle>systemd-fsck@.service</refentrytitle><manvolnum>8</manvolnum></citerefentry>,

<citerefentry><refentrytitle>systemd-quotacheck.service</refentrytitle><manvolnum>8</manvolnum></citerefentry>,

<citerefentry><refentrytitle>systemd-journald.service</refentrytitle><manvolnum>8</manvolnum></citerefentry>,

<citerefentry><refentrytitle>systemd-vconsole-setup.service</refentrytitle><manvolnum>8</manvolnum></citerefentry>,

<citerefentry><refentrytitle>systemd-udevd.service</refentrytitle><manvolnum>8</manvolnum></citerefentry>,

<citerefentry project='die-net'><refentrytitle>plymouth</refentrytitle><manvolnum>8</manvolnum></citerefentry>,

<citerefentry><refentrytitle>systemd-cryptsetup-generator</refentrytitle><manvolnum>8</manvolnum></citerefentry>,

<citerefentry><refentrytitle>systemd-fstab-generator</refentrytitle><manvolnum>8</manvolnum></citerefentry>,

<citerefentry><refentrytitle>systemd-gpt-auto-generator</refentrytitle><manvolnum>8</manvolnum></citerefentry>,

<citerefentry><refentrytitle>systemd-modules-load.service</refentrytitle><manvolnum>8</manvolnum></citerefentry>,

<citerefentry><refentrytitle>systemd-backlight@.service</refentrytitle><manvolnum>8</manvolnum></citerefentry>,

<citerefentry><refentrytitle>systemd-rfkill@.service</refentrytitle><manvolnum>8</manvolnum></citerefentry>,

<citerefentry><refentrytitle>systemd-hibernate-resume-generator</refentrytitle><manvolnum>8</manvolnum></citerefentry>

</para>

</refsect1>

</refentry>