systemd-boot
systemd-boot, previously called gummiboot (German for: 'rubber dinghy'), is a simple UEFI boot manager which executes configured EFI images. The default entry is selected by a configured pattern (glob) or an on-screen menu to be navigated via arrow keys. It is included with systemd, which is installed on an Arch system by default.
It is simple to configure but can only start EFI executables such as the Linux kernel EFISTUB, UEFI shell, GRUB, or the Windows Boot Manager.
Installation
Installing the EFI boot manager
To install the systemd-boot EFI boot manager, first make sure the system has booted into UEFI mode and that UEFI variables are accessible. This can be checked by running the command efivar --list
or, if efivar is not installed, by running ls /sys/firmware/efi/efivars
(if the directory exists, the system is booted into UEFI mode.)
Throughout, esp
will be used to denote the ESP mountpoint, e.g. /efi
or /boot
. This assumes that you have chroot
ed to your system's mount point.
With the EFI system partition (ESP) mounted to esp
, use bootctl
to install systemd-boot to the ESP:
# bootctl install
This will copy the systemd-boot boot loader to the ESP: on a x64 architecture system /usr/lib/systemd/boot/efi/systemd-bootx64.efi
will be copied to esp/EFI/systemd/systemd-bootx64.efi
and esp/EFI/BOOT/BOOTX64.EFI
, and systemd-boot will be set as the default EFI application.
bootctl install
, systemd-boot will try to locate the ESP at /efi
, /boot
, and /boot/efi
. Setting esp
to a different location requires passing the --esp-path=esp
option. (See the man page for details.)/EFI/BOOT/BOOTX64.EFI
, for example Microsoft's version of this file.To conclude the installation, configure systemd-boot.
Installation using XBOOTLDR
A separate /boot partition of type "Linux extended boot" (XBOOTLDR) can be created to keep the kernel and initramfs separate from the ESP. This is particularly helpful to dual boot with Windows with an existing ESP that is too small.
Prepare an ESP as usual and create another partition for XBOOTLDR on the same physical drive. The XBOOTLDR partition must have a partition type GUID of bc13c2ff-59e6-4262-a352-b275fd6f7172
[1]. The size of the XBOOTLDR partition should be large enough to accommodate all of the kernels you are going to install.
- systemd-boot does not do a file system check like it does for the ESP. Hence, it is possible to use any file system that your UEFI implementation can read.
- UEFI may skip loading partitions other than the ESP when a "fast boot" mode is enabled. This can lead to systemd-boot failing to find entries on the XBOOTLDR partition; in that case, disable "fast boot" mode.
- The XBOOTLDR partition must be on the same physical disk as the ESP for systemd-boot to recognize it.
During install, mount the ESP to /mnt/efi
and the XBOOTLDR partition to /mnt/boot
.
Once in chroot, use the command:
# bootctl --esp-path=/efi --boot-path=/boot install
To conclude the installation, configure systemd-boot.
Updating the EFI boot manager
Whenever there is a new version of systemd-boot, the EFI boot manager can be optionally reinstalled by the user. This can be performed manually, or the update can be automatically triggered using pacman hooks. The two approaches are described thereafter.
Manual update
Use bootctl
to update systemd-boot:
# bootctl update
bootctl install
, systemd-boot will try to locate the ESP at /efi
, /boot
, and /boot/efi
. Setting esp
to a different location requires passing the --esp-path=esp
option.Automatic update
Systemd service
As of version 250, systemd ships with systemd-boot-update.service
. Enabling this service will update the bootloader upon the next boot.
If you prefer using a pacman hook instead (as that will update the bootloader immediately after the systemd package has been upgraded), see the section below.
Pacman hook
The package systemd-boot-pacman-hookAUR provides a pacman hook to automate the process of updating the bootloader. Installing the package adds a hook which will be executed every time the systemd package is upgraded. Alternatively, to replicate what the systemd-boot-pacman-hook package does without installing it, place the following pacman hook in the /etc/pacman.d/hooks/
directory:
/etc/pacman.d/hooks/100-systemd-boot.hook
[Trigger] Type = Package Operation = Upgrade Target = systemd [Action] Description = Updating systemd-boot When = PostTransaction Exec = /usr/bin/bootctl update
If you have Secure Boot enabled, you may want to install a pacman hook to automatically re-sign the kernel and bootloader whenever the former is updated:
/etc/pacman.d/hooks/99-secureboot.hook
[Trigger] Operation = Install Operation = Upgrade Type = Package Target = linux Target = systemd [Action] Description = Signing Kernel for SecureBoot When = PostTransaction Exec = /usr/bin/find /boot -type f ( -name vmlinuz-* -o -name systemd* ) -exec /usr/bin/sh -c 'if ! /usr/bin/sbverify --list {} 2>/dev/null | /usr/bin/grep -q "signature certificates"; then /usr/bin/sbsign --key db.key --cert db.crt --output "$1" "$1"; fi' _ {} ; Depends = sbsigntools Depends = findutils Depends = grep
The Target
needs to be duplicated each time you add a new package upgrade trigger. With respect to the find
statement, since we had a condition with the filenames and ALPM hooks being being split on spaces, we had to surround the whole statement by quotes in order for the hook to be parsed properly. Since systemd-boot is located in sub-directories, the depth needed to be adjusted as well - we removed the -maxdepth
argument. In order to avoid trouble if you are unsure, try reinstalling the package you want to test to see if the hook (and the signing) is processed successfully. See Pacman#Hooks or alpm-hooks(5) for more information.
Configuration
Loader configuration
The loader configuration is stored in the file esp/loader/loader.conf
. See loader.conf(5) § OPTIONS for details.
A loader configuration example is provided below:
esp/loader/loader.conf
default arch.conf timeout 4 console-mode max editor no
- systemd-boot does not accept tabs for indentation, use spaces instead.
-
default
andtimeout
can be changed in the boot menu itself and changes will be stored as EFI variablesLoaderEntryDefault
andLoaderConfigTimeout
, overriding these options. -
bootctl set-default ""
can be used to clear the EFI variable overriding thedefault
option. - A basic loader configuration file is located at
/usr/share/systemd/bootctl/loader.conf
.
Adding loaders
systemd-boot will search for boot menu items in esp/loader/entries/*.conf
and additionally in boot/loader/entries/*.conf
if using XBOOTLDR. Note that entries in esp
can only use files (e.g. kernels, initramfs, images, etc.) in esp
. Similarly, entries in boot
can only use files in boot
.
The possible options are:
-
title
– operating system name. Required. -
version
– kernel version, shown only when multiple entries with same title exist. Optional. -
machine-id
– machine identifier from/etc/machine-id
, shown only when multiple entries with same title and version exist. Optional. -
efi
– EFI program to start, relative to your ESP (esp
); e.g./vmlinuz-linux
. Either this parameter orlinux
(see below) is required. -
options
– space-separated command line options to pass to the EFI program or kernel parameters. Optional, but you will need at leastroot=dev
if booting Linux. This parameter can be omitted if the root partition is assigned the correct Root Partition Type GUID as defined in Discoverable Partitions Specification and if thesystemd
mkinitcpio hook is present.
For Linux boot, you can also use linux
instead of efi
. Or initrd
in addition to options
. The syntax is:
-
linux
orinitrd
followed by the relative path of the corresponding files in the ESP; e.g./vmlinuz-linux
; this will be automatically translated intoefi path
andoptions initrd=path
– this syntax is only supported for convenience and has no differences in function.
options
is present in a boot entry and Secure Boot is disabled, the value of options
will override any .cmdline
string embedded in the EFI image that is specified by efi
or linux
(see #Preparing a unified kernel image). With Secure Boot, however, options
(and any edits made to the kernel command line in the bootloader UI) will be ignored, and only the embedded .cmdline
will be used. An example of loader files launching Arch from a volume labeled arch_os
and loading Intel CPU microcode is:
esp/loader/entries/arch.conf
title Arch Linux linux /vmlinuz-linux initrd /intel-ucode.img initrd /initramfs-linux.img options root="LABEL=arch_os" rw
esp/loader/entries/arch-fallback.conf
title Arch Linux (fallback initramfs) linux /vmlinuz-linux initrd /intel-ucode.img initrd /initramfs-linux-fallback.img options root="LABEL=arch_os" rw
systemd-boot will automatically check at boot time for Windows Boot Manager at the location /EFI/Microsoft/Boot/Bootmgfw.efi
, UEFI shell /shellx64.efi
and EFI Default Loader /EFI/BOOT/bootx64.efi
, as well as specially prepared kernel files found in /EFI/Linux/
. When detected, corresponding entries with titles auto-windows
, auto-efi-shell
and auto-efi-default
, respectively, will be generated. These entries do not require manual loader configuration. However, it does not auto-detect other EFI applications (unlike rEFInd), so for booting the Linux kernel, manual configuration entries must be created.
- The available boot entries which have been configured can be listed with the command
bootctl list
. - An example entry file is located at
/usr/share/systemd/bootctl/arch.conf
. - The kernel parameters for scenarios such as LVM, LUKS or dm-crypt can be found on the relevant pages.
EFI Shells or other EFI applications
In case you installed an EFI shell or an other EFI application into the ESP, you can use the following snippets.
efi
line is relative to your esp mount point. If you are mounted on /boot
and your EFI binaries reside at /boot/EFI/xx.efi
and /boot/yy.efi
, then you would specify the parameters as efi /EFI/xx.efi
and efi /yy.efi
respectively.esp/loader/entries/fwupd.conf
title Firmware updator efi /EFI/fwupx64.efi
esp/loader/entries/gdisk.conf
title GPT fdisk (gdisk) efi /EFI/tools/gdisk_x64.efi
Booting into EFI Firmware Setup
Most system firmware configured for EFI booting will add its own efibootmgr entries to boot into UEFI Firmware Setup.
Support hibernation
Kernel parameters editor with password protection
Alternatively you can install systemd-boot-passwordAUR which supports password
basic configuration option. Use sbpctl generate
to generate a value for this option.
Install systemd-boot-password with the following command:
# sbpctl install esp
With enabled editor you will be prompted for your password before you can edit kernel parameters.
Tips and tricks
See systemd-boot(7) § KEY BINDINGS for the available key bindings inside the boot menu.
Choosing next boot
The boot manager is integrated with the systemctl command, allowing you to choose what option you want to boot after a reboot. For example, suppose you have built a custom kernel and created an entry file esp/loader/entries/arch-custom.conf
to boot into it, you can just launch
$ systemctl reboot --boot-loader-entry=arch-custom.conf
and your system will reboot into that entry maintaining the default option intact for subsequent boots. To see a list of possible entries pass the --boot-loader-entry=help
option.
If you want to boot into the firmware of your motherboard directly, then you can use this command:
$ systemctl reboot --firmware-setup
Unified kernel images
Unified kernel images in esp/EFI/Linux/
are automatically sourced by systemd-boot, and do not need an entry in /boot/loader/entries
.
/boot/loader/entries
will be booted first if no default
is set in /boot/loader/loader.conf
. Remove those entries, or set the default with the full file name, ie default=archlinux-linux.efi
Grml on ESP
PKGBUILD
is available: grml-systemd-bootAUR.Grml is a small live system with a collection of software for system administration and rescue.
In order to install Grml on the ESP, we only need to copy the kernel vmlinuz
, the initramfs initrd.img
, and the squashed image grml64-small.squashfs
from the iso file to the ESP. To do so, first download grml64-small.iso and mount the file (the mountpoint is henceforth denoted mnt); the kernel and initramfs are located in mnt/boot/grml64small/
, and the squashed image resides in mnt/live/grml64-small/
.
Next, create a directory for Grml in your ESP,
# mkdir -p esp/grml
and copy the above-mentioned files in there:
# cp mnt/boot/grml64small/vmlinuz esp/grml # cp mnt/boot/grml64small/initrd.img esp/grml # cp mnt/live/grml64-small/grml64-small.squashfs esp/grml
In the last step, create an entry for the systemd-boot loader: In esp/loader/entries
create a grml.conf
file with the following content:
esp/loader/entries/grml.conf
title Grml Live Linux linux /grml/vmlinuz initrd /grml/initrd.img options apm=power-off boot=live live-media-path=/grml/ nomce net.ifnames=0
For an overview of the available boot options, consult the cheatcode for Grml.
systemd-boot on BIOS systems
If you need a bootloader for BIOS systems that follows The Boot Loader Specification, then systemd-boot can be pressed into service on BIOS systems. The Clover boot loader supports booting from BIOS systems and provides a simulated EFI environment.
Troubleshooting
Installing after booting in BIOS mode
If booted in BIOS mode, you can still install systemd-boot, however this process requires you to tell firmware to launch systemd-boot's EFI file at boot, usually via two ways:
- you have a working EFI Shell somewhere else.
- your firmware interface provides a way of properly setting the EFI file that needs to be loaded at boot time.
If you can do it, the installation is easier: go into your EFI Shell or your firmware configuration interface and change your machine's default EFI file to esp/EFI/systemd/systemd-bootx64.efi
.
Manual entry using efibootmgr
If the bootctl install
command failed, you can create a EFI boot entry manually using efibootmgr:
# efibootmgr --create --disk /dev/sdX --part Y --loader "\EFI\systemd\systemd-bootx64.efi" --label "Linux Boot Manager" --verbose
where /dev/sdXY
is the EFI system partition.
\
) as the separatorManual entry using bcdedit from Windows
If for any reason you need to create an EFI boot entry from Windows, you can use the following commands from an Administrator prompt:
> bcdedit /copy {bootmgr} /d "Linux Boot Manager" > bcdedit /set {guid} path \EFI\systemd\systemd-bootx64.efi
Replace guid
with the id returned by the first command. You can also set it as the default entry using
> bcdedit /default {guid}
Menu does not appear after Windows upgrade
See UEFI#Windows changes boot order.