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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 that the system has booted into UEFI mode and 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 chrooted to your system's mount point.

With the EFI system partition (ESP) mounted to `esp`, use bootctl(1) 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.

Note:

- When running `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 bootctl(1) § OPTIONS for details.)
- Installing systemd-boot will overwrite any existing `esp/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.

Note:

- 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 the "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 done manually or automatically; the two approaches are described thereafter.

Note: The EFI boot manager is a standalone EFI executable and any version can be used to boot the system (partial updates do not apply, since pacman only installs the systemd-boot installer, not systemd-boot itself.) However, new versions may add new features or fix bugs, so it is probably a good idea to update systemd-boot.

#### Manual update

Use bootctl to update systemd-boot:

    # bootctl update

Note: As with `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

To update systemd-boot automatically, either use a systemd service or a pacman hook. The two methods are described below.

##### systemd service

As of version 250, systemd ships with `systemd-boot-update.service`. Enabling this service will update the bootloader upon the next boot.

Warning: If you have Secure Boot enabled, you need to sign your bootloader after updating. See #pacman hook below for an example of how to do so.

##### pacman hook

The package systemd-boot-pacman-hookAUR adds a pacman hook which is executed every time systemd is upgraded.

Rather than installing systemd-boot-pacman-hook, you may prefer to manually place the following file in `/etc/pacman.d/hooks/`:

    /etc/pacman.d/hooks/95-systemd-boot.hook

    [Trigger]
    Type = Package
    Operation = Upgrade
    Target = systemd

    [Action]
    Description = Gracefully upgrading systemd-boot...
    When = PostTransaction
    Exec = /usr/bin/systemctl restart systemd-boot-update.service

If you have Secure Boot enabled, you may want to add a pacman hook to automatically re-sign the kernel and bootloader upon every upgrade of the respective packages:

    /etc/pacman.d/hooks/99-secureboot.hook

    [Trigger]
    Operation = Install
    Operation = Upgrade
    Type = Package
    Target = linux
    Target = systemd

    [Action]
    Description = Signing Kernel for Secure Boot
    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 keyfile --cert certfile --output "$1" "$1"; fi' _ {} ;
    Depends = sbsigntools
    Depends = findutils
    Depends = grep

Make sure that the parameters `--key keyfile --cert certfile` point to your signing key and certificate. For better understanding of this hook, consult sbverify(1) and sbsign(1).

## 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

Tip:

- systemd-boot does not accept tabs for indentation, use spaces instead.
- `default` and `timeout` can be changed in the boot menu itself and changes will be stored as EFI variables `LoaderEntryDefault` and `LoaderConfigTimeout`, overriding these options.
- `bootctl set-default ""` and `bootctl set-timeout ""` can be used to clear the EFI variables overriding the `default` and `timeout` options, respectively.
- 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`.

This section is being considered for removal.

Reason: Duplicates https://uapi-group.org/specifications/specs/boot_loader_specification/#type-1-boot-loader-specification-entries. (Discuss in Talk:Systemd-boot#Potential removal of "Loader configuration" section)

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 or `linux` (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 least `root=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 the `systemd` 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` or `initrd` followed by the relative path of the corresponding files in the ESP; e.g. `/vmlinuz-linux`; this will be automatically translated into `efi path` and `options initrd=path` – this syntax is only supported for convenience and has no differences in function.

Note: If `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 Unified kernel image#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.

Tip:

- 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 with the package edk2-shell, systemd-boot will auto-detect and create a new entry if the EFI file is placed in `esp/shellx64.efi`. To perform this and example command after installing the package would be:

    # cp /usr/share/edk2-shell/x64/Shell.efi /boot/shellx64.efi

Otherwise in case you installed other EFI applications into the ESP, you can use the following snippets.

Note: The file path parameter for the `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/tools/fwupdx64.efi

    esp/loader/entries/gdisk.conf

    title  GPT fdisk (gdisk)
    efi     /EFI/tools/gdisk_x64.efi

#### Boot from another disk

systemd-boot cannot launch binaries from partitions other than the ESP or the XBOOTLDR partition, but it can run an external script to do so.

First we need to install edk2-shell (will be the interpreter to be used) and using the EFI shell (as explained above) we can use the map command to take notes of the FS alias (ex: HD0a66666a2) and the full path of the destination EFI file (ex: EFI\Microsoft\Boot\Bootmgfw.efi).

Then using the exit command we can boot back into Linux where we can create the new entry. To do so we need to first create in the root of the esp mount point a .nsh filename with the FS alias, a colon and the EFI path, here an example:

    esp/windows.nsh

    HD0a66666a2:EFI\Microsoft\Boot\Bootmgfw.efi

Once we created this file we can proceed to create the loader entry to run the script:

    esp/loader/entries/windows.conf

    title  Windows
    efi     /shellx64.efi
    options -nointerrupt -noconsolein -noconsoleout windows.nsh

Its important that the efi path matches where the edk2-shell has been copied in the esp partition, and the last argument of options matches the .nsh filename in the root of the esp partition. Also note that the edk2-shell EFI file can be moved to avoid the entry auto-creation of systemd-boot.

### Booting into EFI Firmware Setup

systemd-boot will automatically add an entry to boot into UEFI Firmware Setup if your device's firmware supports rebooting into setup from the OS.

### Support hibernation

See Suspend and hibernate.

### 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

### Keys inside the boot menu

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 `esp/loader/entries`. (Note that unified kernel images must have a `.efi` extension to be identified by systemd-boot.)

Tip: Files in `esp/loader/entries` will be booted first if no `default` is set in `esp/loader/loader.conf`. Remove those entries, or set the default with the full file name, ie `default archlinux-linux.efi`

### Grml on ESP

Note: The following instructions are not exclusive to Grml. With slight adjustments, installing other software (e.g., SystemRescueCD) is possible.
Tip: A `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

Note: This is not recommended.

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`.

Note: The firmware interface of Dell Latitude series provides everything you need to setup EFI boot but the EFI Shell will not be able to write to the computer's ROM.

### 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" --unicode

where `/dev/sdXY` is the EFI system partition.

Note: The path to the EFI image must use the backslash (`\`) as the separator

### Manual 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.

## See also

- https://www.freedesktop.org/wiki/Software/systemd/systemd-boot/
- https://github.com/systemd/systemd/tree/master/src/boot/efi
- https://bbs.archlinux.org/viewtopic.php?id=254374
- https://uapi-group.org/specifications/specs/boot_loader_specification/

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- Boot loaders

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