NAME¶
bootctl - Control EFI firmware boot settings and manage boot
loader
SYNOPSIS¶
bootctl [OPTIONS...] {COMMAND}
DESCRIPTION¶
bootctl can check the EFI firmware and boot loader status,
list and manage available boot loaders and boot loader entries, and install,
update, or remove the systemd-boot(7) boot loader on the current
system.
GENERIC EFI FIRMWARE/BOOT LOADER COMMANDS¶
These commands are available on any EFI system, regardless of the
boot loader used.
status
Shows brief information about the system firmware, the
boot loader that was used to boot the system, the boot loaders currently
available in the ESP, the boot loaders listed in the firmware's list of boot
loaders and the current default boot loader entry. If no command is specified,
this is the implied default.
reboot-to-firmware [BOOL]
Query or set the "Reboot-Into-Firmware-Setup"
flag of the EFI firmware. Takes a boolean argument which controls whether to
show the firmware setup on next system reboot. If the argument is omitted
shows the current status of the flag, or whether the flag is supported. This
controls the same flag as systemctl reboot --firmware-setup, but is
more low-level and allows setting the flag independently from actually
requesting a reboot.
systemd-efi-options [STRING]
When called without the optional argument, prints the
current value of the "SystemdOptions" EFI variable. When called with
an argument, sets the variable to that value. See
systemd(1) for the
meaning of that variable.
BOOT LOADER SPECIFICATION COMMANDS¶
These commands are available for all boot loaders that implement
the Boot Loader Specification[1] and/or the Boot Loader
Interface[2], such as systemd-boot.
list
Shows all available boot loader entries implementing the
Boot Loader Specification[1], as well as any other entries discovered
or automatically generated by a boot loader implementing the Boot Loader
Interface[2].
set-default ID, set-oneshot ID
Sets the default boot loader entry. Takes a single boot
loader entry ID string as argument. The set-oneshot command will set
the default entry only for the next boot, the set-default will set it
persistently for all future boots. Optionally, the boot loader entry ID may be
specified as one of: @default, @oneshot or @current,
which correspond to the current default boot loader entry for all future
boots, the current default boot loader entry for the next boot, and the
currently booted boot loader entry. These special IDs are resolved to the
current values of the EFI variables LoaderEntryDefault,
LoaderEntryOneShot and LoaderEntrySelected, see Boot Loader
Specification[1] for details. These special IDs are primarily useful as a
quick way to persistently make the currently booted boot loader entry the
default choice, or to upgrade the default boot loader entry for the next boot
to the default boot loader entry for all future boots, but may be used for
other operations too. When an empty string ("") is specified as an
ID, then the corresponding EFI variable will be unset.
SYSTEMD-BOOT COMMANDS¶
These commands manage the systemd-boot EFI boot loader, and
do not work in conjunction with other boot loaders.
install
Installs systemd-boot into the EFI system
partition. A copy of systemd-boot will be stored as the EFI
default/fallback loader at ESP/EFI/BOOT/BOOT*.EFI. The boot loader is
then added to the top of the firmware's boot loader list.
update
Updates all installed versions of
systemd-boot(7),
if the available version is newer than the version installed in the EFI system
partition. This also includes the EFI default/fallback loader at
ESP/EFI/BOOT/BOOT*.EFI. The boot loader is then added to end of the
firmware's boot loader list if missing.
remove
Removes all installed versions of systemd-boot
from the EFI system partition and the firmware's boot loader list.
is-installed
Checks whether systemd-boot is installed in the
ESP. Note that a single ESP might host multiple boot loaders; this hence
checks whether systemd-boot is one (of possibly many) installed boot
loaders — and neither whether it is the default nor whether it is
registered in any EFI variables.
random-seed
Generates a random seed and stores it in the EFI System
Partition, for use by the
systemd-boot boot loader. Also, generates a
random 'system token' and stores it persistently as an EFI variable, if one
has not been set before. If the boot loader finds the random seed in the ESP
and the system token in the EFI variable it will derive a random seed to pass
to the OS and a new seed to store in the ESP from the combination of both. The
random seed passed to the OS is credited to the kernel's entropy pool by the
system manager during early boot, and permits userspace to boot up with an
entropy pool fully initialized very early on. Also see
systemd-boot-system-token.service(8).
See Random Seeds[3] for further information.
OPTIONS¶
The following options are understood:
--esp-path=
Path to the EFI System Partition (ESP). If not specified,
/efi/, /boot/, and /boot/efi/ are checked in turn. It is recommended to mount
the ESP to /efi/, if possible.
--boot-path=
Path to the Extended Boot Loader partition, as defined in
the Boot Loader Specification[1]. If not specified, /boot/ is checked.
It is recommended to mount the Extended Boot Loader partition to /boot/, if
possible.
-p, --print-esp-path
This option modifies the behaviour of status. Only
prints the path to the EFI System Partition (ESP) to standard output and
exits.
-x, --print-boot-path
This option modifies the behaviour of
status. Only
prints the path to the Extended Boot Loader partition if it exists, and the
path to the ESP otherwise to standard output and exit. This command is useful
to determine where to place boot loader entries, as they are preferably placed
in the Extended Boot Loader partition if it exists and in the ESP otherwise.
Boot Loader Specification Type #1 entries should generally be
placed in the directory "$(bootctl -x)/loader/entries/". Existence
of that directory may also be used as indication that boot loader entry
support is available on the system. Similarly, Boot Loader Specification
Type #2 entries should be placed in the directory "$(bootctl
-x)/EFI/Linux/".
Note that this option (similar to the --print-booth-path
option mentioned above), is available independently from the boot loader
used, i.e. also without systemd-boot being installed.
--no-variables
Do not touch the firmware's boot loader list stored in
EFI variables.
--graceful
Ignore failure when the EFI System Partition cannot be
found, or when EFI variables cannot be written. Currently only applies to
random seed operations.
--no-pager
Do not pipe output into a pager.
-h, --help
Print a short help text and exit.
--version
Print a short version string and exit.
EXIT STATUS¶
On success, 0 is returned, a non-zero failure code otherwise.
ENVIRONMENT¶
If $SYSTEMD_RELAX_ESP_CHECKS=1 is set the validation checks
for the ESP are relaxed, and the path specified with --esp-path= may
refer to any kind of file system on any kind of partition.
Similarly, $SYSTEMD_RELAX_XBOOTLDR_CHECKS=1 turns off some
validation checks for the Extended Boot Loader partition.
NOTES¶
- 1.
- Boot Loader Specification
- 2.
- Boot Loader Interface
- 3.
- Random Seeds
