KERNEL-COMMAND-LINE(7)       kernel-command-line      KERNEL-COMMAND-LINE(7)

NAME         top

       kernel-command-line - Kernel command line parameters

SYNOPSIS         top


DESCRIPTION         top

       The kernel, the initial RAM disk (initrd) and basic userspace
       functionality may be configured at boot via kernel command line

       For command line parameters understood by the kernel, please see
       kernel-parameters.html[1] and bootparam(7).

       For command line parameters understood by the initial RAM disk,
       please see dracut.cmdline(7), or the documentation of the specific
       initrd implementation of your installation.


       systemd.unit=, rd.systemd.unit=, systemd.dump_core,
       systemd.crash_chvt, systemd.crash_shell, systemd.crash_reboot,
       systemd.confirm_spawn, systemd.show_status, systemd.log_target=,
       systemd.log_level=, systemd.log_location=, systemd.log_color,
       systemd.default_standard_output=, systemd.default_standard_error=,
       systemd.setenv=, systemd.machine_id=,
           Parameters understood by the system and service manager to
           control system behavior. For details, see systemd(1).

       systemd.mask=, systemd.wants=, systemd.debug_shell
           Additional parameters understood by systemd-debug-generator(8),
           to mask or start specific units at boot, or invoke a debug shell
           on tty9.

           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 systemd-backlight@.service(8) and

           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 systemd-volatile-root.service(8) and

           Parameter understood by both the kernel and the system and
           service manager to control console log verbosity. For details,
           see systemd(1).

           Parameter understood by both the kernel and the system and
           service manager to control console log verbosity. For details,
           see systemd(1).

       -b, rd.emergency, emergency, rd.rescue, rescue, single, s, S, 1, 2,
       3, 4, 5
           Parameters understood by the system and service manager, as
           compatibility and convenience options. For details, see

       locale.LANG=, locale.LANGUAGE=, locale.LC_CTYPE=, locale.LC_NUMERIC=,
       locale.LC_TIME=, locale.LC_COLLATE=, locale.LC_MONETARY=,
       locale.LC_MESSAGES=, locale.LC_PAPER=, locale.LC_NAME=,
       locale.LC_ADDRESS=, locale.LC_TELEPHONE=, locale.LC_MEASUREMENT=,
           Parameters understood by the system and service manager to
           control locale and language settings. For details, see

           Parameters understood by the file system checker services. For
           details, see systemd-fsck@.service(8).

           Parameter understood by the file quota checker service. For
           details, see systemd-quotacheck.service(8).

           Parameters understood by the journal service. For details, see

       vconsole.keymap=, vconsole.keymap_toggle=, vconsole.font=,
       vconsole.font_map=, vconsole.font_unimap=
           Parameters understood by the virtual console setup logic. For
           details, see vconsole.conf(5).

       udev.log_priority=, rd.udev.log_priority=, udev.children_max=,
       rd.udev.children_max=, udev.exec_delay=, rd.udev.exec_delay=,
       udev.event_timeout=, rd.udev.event_timeout=, net.ifnames=
           Parameters understood by the device event managing daemon. For
           details, see systemd-udevd.service(8).

           May be used to disable the Plymouth boot splash. For details, see

       luks=, rd.luks=, luks.crypttab=, rd.luks.crypttab=,,, luks.uuid=, rd.luks.uuid=, luks.options=,
       rd.luks.options=, luks.key=, rd.luks.key=
           Configures the LUKS full-disk encryption logic at boot. For
           details, see systemd-cryptsetup-generator(8).

       fstab=, rd.fstab=
           Configures the /etc/fstab logic at boot. For details, see

       root=, rootfstype=, rootflags=, ro, rw
           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

       roothash=, systemd.verity=, rd.systemd.verity=,
       systemd.verity_root_data=, systemd.verity_root_hash=
           Configures the integrity protection root hash for the root file
           system, and other related parameters. For details, see

       systemd.gpt_auto=, rd.systemd.gpt_auto=
           Configures whether GPT based partition auto-discovery shall be
           attempted. For details, see systemd-gpt-auto-generator(8).

           Overwrites the default start job timeout DefaultTimeoutStartSec=
           at boot. For details, see systemd-system.conf(5).

       modules_load=, rd.modules_load=
           Load a specific kernel module early at boot. For details, see

           Enables resume from hibernation using the specified device. All
           fstab(5)-like paths are supported. For details, see

           Takes a boolean argument, defaults to on. If off,
           systemd-firstboot.service(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.

SEE ALSO         top

       systemd(1), bootparam(7), dracut.cmdline(7),
       systemd-debug-generator(8), systemd-fsck@.service(8),
       systemd-quotacheck.service(8), systemd-journald.service(8),
       systemd-vconsole-setup.service(8), systemd-udevd.service(8),
       plymouth(8), systemd-cryptsetup-generator(8),
       systemd-veritysetup-generator(8), systemd-fstab-generator(8),
       systemd-gpt-auto-generator(8), systemd-volatile-root.service(8),
       systemd-modules-load.service(8), systemd-backlight@.service(8),
       systemd-rfkill.service(8), systemd-hibernate-resume-generator(8),

NOTES         top

        1. kernel-parameters.html

COLOPHON         top

       This page is part of the systemd (systemd system and service manager)
       project.  Information about the project can be found at 
       ⟨⟩.  If you have a bug
       report for this manual page, see
       ⟨⟩.  This
       page was obtained from the project's upstream Git repository
       ⟨⟩ on 2018-02-02.  (At that
       time, the date of the most recent commit that was found in the repos‐
       itory was 2018-02-02.)  If you discover any rendering problems in
       this HTML version of the page, or you believe there is a better or
       more up-to-date source for the page, or you have corrections or
       improvements to the information in this COLOPHON (which is not part
       of the original manual page), send a mail to

systemd 234                                           KERNEL-COMMAND-LINE(7)

Pages that refer to this page: systemd(1)systemd-nspawn(1)systemd.exec(5)systemd.directives(7)systemd.index(7)systemd-debug-generator(8)systemd-fstab-generator(8)systemd-hibernate-resume-generator(8)systemd-volatile-root.service(8)