'\" t
.TH "KERNEL\-COMMAND\-LINE" "7" "" "systemd 241" "kernel-command-line"
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.SH "NAME"
kernel-command-line \- Kernel command line parameters
.SH "SYNOPSIS"
.PP
/proc/cmdline
.SH "DESCRIPTION"
.PP
The kernel, the initial RAM disk (initrd) and basic userspace functionality may be configured at boot via kernel command line arguments\&.
.PP
For command line parameters understood by the kernel, please see
\m[blue]\fBkernel\-parameters\&.html\fR\m[]\&\s-2\u[1]\d\s+2
and
\fBbootparam\fR(7)\&.
.PP
For command line parameters understood by the initial RAM disk, please see
\fBdracut.cmdline\fR(7), or the documentation of the specific initrd implementation of your installation\&.
.SH "CORE OS COMMAND LINE ARGUMENTS"
.PP
\fIsystemd\&.unit=\fR, \fIrd\&.systemd\&.unit=\fR, \fIsystemd\&.dump_core\fR, \fIsystemd\&.early_core_pattern=\fR, \fIsystemd\&.crash_chvt\fR, \fIsystemd\&.crash_shell\fR, \fIsystemd\&.crash_reboot\fR, \fIsystemd\&.confirm_spawn\fR, \fIsystemd\&.service_watchdogs\fR, \fIsystemd\&.show_status\fR, \fIsystemd\&.log_target=\fR, \fIsystemd\&.log_level=\fR, \fIsystemd\&.log_location=\fR, \fIsystemd\&.log_color\fR, \fIsystemd\&.default_standard_output=\fR, \fIsystemd\&.default_standard_error=\fR, \fIsystemd\&.setenv=\fR, \fIsystemd\&.machine_id=\fR, \fIsystemd\&.unified_cgroup_hierarchy\fR, \fIsystemd\&.legacy_systemd_cgroup_controller\fR
.RS 4
Parameters understood by the system and service manager to control system behavior\&. For details, see
\fBsystemd\fR(1)\&.
.RE
.PP
\fIsystemd\&.mask=\fR, \fIsystemd\&.wants=\fR, \fIsystemd\&.debug_shell\fR
.RS 4
Additional parameters understood by
\fBsystemd-debug-generator\fR(8), to mask or start specific units at boot, or invoke a debug shell on tty9\&.
.RE
.PP
\fIsystemd\&.run=\fR, \fIsystemd\&.run_success_action=\fR, \fIsystemd\&.run_failure_action=\fR
.RS 4
Additional parameters understood by
\fBsystemd-run-generator\fR(8), to run a command line specified on the kernel command line as system service after booting up\&.
.RE
.PP
\fIsystemd\&.early_core_pattern=\fR
.RS 4
During early boot, the generation of core dump files is disabled until a core dump handler (if any) takes over\&. This parameter allows to specifies an absolute path where core dump files should be stored until a handler is installed\&. The path should be absolute and may contain specifiers, see
\fBcore\fR(5)
for details\&.
.RE
.PP
\fIsystemd\&.restore_state=\fR
.RS 4
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
\fBsystemd-backlight@.service\fR(8)
and
\fBsystemd-rfkill.service\fR(8)\&.
.RE
.PP
\fIsystemd\&.volatile=\fR
.RS 4
This parameter controls whether the system shall boot up in volatile mode\&. Takes a boolean argument, or the special value
"state"\&. If false (the default), normal boot mode is selected, the root directory and
/var
are mounted as specified on the kernel command line or
/etc/fstab, or otherwise configured\&. If true, full state\-less boot mode is selected\&. In this case the root directory is mounted as volatile memory file system ("tmpfs"), and only
/usr
is mounted from the file system configured as root device, in read\-only mode\&. This enables fully state\-less boots were the vendor\-supplied OS is used as shipped, with only default configuration and no stored state in effect, as
/etc
and
/var
(as well as all other resources shipped in the root file system) are reset at boot and lost on shutdown\&. If this setting is set to
"state"
the root file system is mounted as usual, however
/var
is mounted as a volatile memory file system ("tmpfs"), so that the system boots up with the normal configuration applied, but all state reset at boot and lost at shutdown\&. For details, see
\fBsystemd-volatile-root.service\fR(8)
and
\fBsystemd-fstab-generator\fR(8)\&.
.RE
.PP
\fIquiet\fR
.RS 4
Parameter understood by both the kernel and the system and service manager to control console log verbosity\&. For details, see
\fBsystemd\fR(1)\&.
.RE
.PP
\fIdebug\fR
.RS 4
Parameter understood by both the kernel and the system and service manager to control console log verbosity\&. For details, see
\fBsystemd\fR(1)\&.
.RE
.PP
\fI\-b\fR, \fIrd\&.emergency\fR, \fIemergency\fR, \fIrd\&.rescue\fR, \fIrescue\fR, \fIsingle\fR, \fIs\fR, \fIS\fR, \fI1\fR, \fI2\fR, \fI3\fR, \fI4\fR, \fI5\fR
.RS 4
Parameters understood by the system and service manager, as compatibility and convenience options\&. For details, see
\fBsystemd\fR(1)\&.
.RE
.PP
\fIlocale\&.LANG=\fR, \fIlocale\&.LANGUAGE=\fR, \fIlocale\&.LC_CTYPE=\fR, \fIlocale\&.LC_NUMERIC=\fR, \fIlocale\&.LC_TIME=\fR, \fIlocale\&.LC_COLLATE=\fR, \fIlocale\&.LC_MONETARY=\fR, \fIlocale\&.LC_MESSAGES=\fR, \fIlocale\&.LC_PAPER=\fR, \fIlocale\&.LC_NAME=\fR, \fIlocale\&.LC_ADDRESS=\fR, \fIlocale\&.LC_TELEPHONE=\fR, \fIlocale\&.LC_MEASUREMENT=\fR, \fIlocale\&.LC_IDENTIFICATION=\fR
.RS 4
Parameters understood by the system and service manager to control locale and language settings\&. For details, see
\fBsystemd\fR(1)\&.
.RE
.PP
\fIfsck\&.mode=\fR, \fIfsck\&.repair=\fR
.RS 4
Parameters understood by the file system checker services\&. For details, see
\fBsystemd-fsck@.service\fR(8)\&.
.RE
.PP
\fIquotacheck\&.mode=\fR
.RS 4
Parameter understood by the file quota checker service\&. For details, see
\fBsystemd-quotacheck.service\fR(8)\&.
.RE
.PP
\fIsystemd\&.journald\&.forward_to_syslog=\fR, \fIsystemd\&.journald\&.forward_to_kmsg=\fR, \fIsystemd\&.journald\&.forward_to_console=\fR, \fIsystemd\&.journald\&.forward_to_wall=\fR
.RS 4
Parameters understood by the journal service\&. For details, see
\fBsystemd-journald.service\fR(8)\&.
.RE
.PP
\fIvconsole\&.keymap=\fR, \fIvconsole\&.keymap_toggle=\fR, \fIvconsole\&.font=\fR, \fIvconsole\&.font_map=\fR, \fIvconsole\&.font_unimap=\fR
.RS 4
Parameters understood by the virtual console setup logic\&. For details, see
\fBvconsole.conf\fR(5)\&.
.RE
.PP
\fIudev\&.log_priority=\fR, \fIrd\&.udev\&.log_priority=\fR, \fIudev\&.children_max=\fR, \fIrd\&.udev\&.children_max=\fR, \fIudev\&.exec_delay=\fR, \fIrd\&.udev\&.exec_delay=\fR, \fIudev\&.event_timeout=\fR, \fIrd\&.udev\&.event_timeout=\fR, \fInet\&.ifnames=\fR, \fInet\&.naming\-scheme=\fR
.RS 4
Parameters understood by the device event managing daemon\&. For details, see
\fBsystemd-udevd.service\fR(8)\&.
.RE
.PP
\fIplymouth\&.enable=\fR
.RS 4
May be used to disable the Plymouth boot splash\&. For details, see
\fBplymouth\fR(8)\&.
.RE
.PP
\fIluks=\fR, \fIrd\&.luks=\fR, \fIluks\&.crypttab=\fR, \fIrd\&.luks\&.crypttab=\fR, \fIluks\&.name=\fR, \fIrd\&.luks\&.name=\fR, \fIluks\&.uuid=\fR, \fIrd\&.luks\&.uuid=\fR, \fIluks\&.options=\fR, \fIrd\&.luks\&.options=\fR, \fIluks\&.key=\fR, \fIrd\&.luks\&.key=\fR
.RS 4
Configures the LUKS full\-disk encryption logic at boot\&. For details, see
\fBsystemd-cryptsetup-generator\fR(8)\&.
.RE
.PP
\fIfstab=\fR, \fIrd\&.fstab=\fR
.RS 4
Configures the
/etc/fstab
logic at boot\&. For details, see
\fBsystemd-fstab-generator\fR(8)\&.
.RE
.PP
\fIroot=\fR, \fIrootfstype=\fR, \fIrootflags=\fR, \fIro\fR, \fIrw\fR
.RS 4
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
\fBsystemd-fstab-generator\fR(8)\&.
.RE
.PP
\fImount\&.usr=\fR, \fImount\&.usrfstype=\fR, \fImount\&.usrflags=\fR
.RS 4
Configures the /usr file system (if required) and its file system type and mount options\&. For details, see
\fBsystemd-fstab-generator\fR(8)\&.
.RE
.PP
\fIroothash=\fR, \fIsystemd\&.verity=\fR, \fIrd\&.systemd\&.verity=\fR, \fIsystemd\&.verity_root_data=\fR, \fIsystemd\&.verity_root_hash=\fR
.RS 4
Configures the integrity protection root hash for the root file system, and other related parameters\&. For details, see
\fBsystemd-veritysetup-generator\fR(8)\&.
.RE
.PP
\fIsystemd\&.gpt_auto=\fR, \fIrd\&.systemd\&.gpt_auto=\fR
.RS 4
Configures whether GPT based partition auto\-discovery shall be attempted\&. For details, see
\fBsystemd-gpt-auto-generator\fR(8)\&.
.RE
.PP
\fIsystemd\&.default_timeout_start_sec=\fR
.RS 4
Overwrites the default start job timeout
\fIDefaultTimeoutStartSec=\fR
at boot\&. For details, see
\fBsystemd-system.conf\fR(5)\&.
.RE
.PP
\fIsystemd\&.watchdog_device=\fR
.RS 4
Overwrites the watchdog device path
\fIWatchdogDevice=\fR\&. For details, see
\fBsystemd-system.conf\fR(5)\&.
.RE
.PP
\fImodules_load=\fR, \fIrd\&.modules_load=\fR
.RS 4
Load a specific kernel module early at boot\&. For details, see
\fBsystemd-modules-load.service\fR(8)\&.
.RE
.PP
\fIresume=\fR
.RS 4
Enables resume from hibernation using the specified device\&. All
\fBfstab\fR(5)\-like paths are supported\&. For details, see
\fBsystemd-hibernate-resume-generator\fR(8)\&.
.RE
.PP
\fIsystemd\&.firstboot=\fR
.RS 4
Takes a boolean argument, defaults to on\&. If off,
\fBsystemd-firstboot.service\fR(8)
will not query the user for basic system settings, even if the system boots up for the first time and the relevant settings are not initialized yet\&.
.RE
.SH "SEE ALSO"
.PP
\fBsystemd\fR(1),
\fBsystemd-system.conf\fR(5),
\fBbootparam\fR(7),
\fBdracut.cmdline\fR(7),
\fBsystemd-debug-generator\fR(8),
\fBsystemd-fsck@.service\fR(8),
\fBsystemd-quotacheck.service\fR(8),
\fBsystemd-journald.service\fR(8),
\fBsystemd-vconsole-setup.service\fR(8),
\fBsystemd-udevd.service\fR(8),
\fBplymouth\fR(8),
\fBsystemd-cryptsetup-generator\fR(8),
\fBsystemd-veritysetup-generator\fR(8),
\fBsystemd-fstab-generator\fR(8),
\fBsystemd-gpt-auto-generator\fR(8),
\fBsystemd-volatile-root.service\fR(8),
\fBsystemd-modules-load.service\fR(8),
\fBsystemd-backlight@.service\fR(8),
\fBsystemd-rfkill.service\fR(8),
\fBsystemd-hibernate-resume-generator\fR(8),
\fBsystemd-firstboot.service\fR(8)
.SH "NOTES"
.IP " 1." 4
kernel-parameters.html
.RS 4
\%https://www.kernel.org/doc/html/latest/admin-guide/kernel-parameters.html
.RE