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 or a glob pattern 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.
If set to @saved the chosen entry will be saved as an EFI
variable on every boot and automatically selected the next time the boot
loader starts.
When an empty string ("") is specified as an ID, then
the corresponding EFI variable will be unset.
set-timeout TIMEOUT, set-timeout-oneshot
TIMEOUT
Sets the boot loader menu timeout in seconds. The
set-timeout-oneshot command will set the timeout only for the next
boot. See
systemd.time(7) for details about the syntax of time spans.
If this is set to menu-hidden or 0 no menu is shown
and the default entry will be booted immediately, while setting this to
menu-force disables the timeout while always showing the menu. When
an empty string ("") is specified the bootloader will revert to
its default menu timeout.
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, when EFI variables cannot be written, or a different or newer boot
loader is already installed. Currently only applies to random seed and update
operations.
--make-machine-id-directory=yes|no
Control creation and deletion of the top-level machine ID
directory on the file system containing boot loader entries (i.e. beneath the
file system returned by the
--print-boot-path option, see above) during
install and
remove, respectively. Defaults to "no".
See
machine-id(5) for details about the machine ID concept and file.
Overriding this may be desirable to hide the machine ID from the
(unencrypted) ESP, configure a kernel-install(8) script, or,
conversely, commit a transient machine ID.
The top-level machine ID directory is useful to allow smooth
multi-boot installations: each installed OS instance will have a different
machine ID and thus a separate directory to place its boot-time resources
in. If this feature is turned off with this option, care needs to be taken
that multiple OS instances do not place conflicting files on the shared ESP
and Extended Boot Loader Partitions, or that multiple OS instances are not
possible.
--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.
SIGNED .EFI FILES¶
bootctl install and update will look for a
systemd-boot file ending with the ".efi.signed" suffix
first, and copy that instead of the normal ".efi" file. This
allows distributions or end-users to provide signed images for UEFI
SecureBoot.
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.
SEE ALSO¶
systemd-boot(7), Boot Loader Specification[1],
Boot Loader Interface[2],
systemd-boot-system-token.service(8)
NOTES¶
- 1.
- Boot Loader Specification
- 2.
- Boot Loader Interface
- 3.
- Random Seeds