SYSTEMD-BOOT(7)

  .SH "NAME" systemd-boot, sd-boot - A simple UEFI boot manager
  .SH "DESCRIPTION"

    .PP systemd-boot (short: sd-boot) is a simple UEFI boot manager. It provides a graphical menu to select the entry to boot and an editor for the kernel command line. systemd-boot supports systems with UEFI firmware only.
    .PP systemd-boot loads boot entry information from the EFI system partition (ESP), usually mounted at /boot, /efi, or /boot/efi during OS runtime. Configuration file fragments, kernels, initrds and other EFI images to boot generally need to reside on the ESP. Linux kernels must be built with CONFIG_EFI_STUB to be able to be directly executed as an EFI image. During boot systemd-boot automatically assembles a list of boot entries from the following sources:

    • Boot entries defined with Boot Loader Specification[1] description files located in /loader/entries/ on the ESP. These usually describe Linux kernel images with associated initrd images, but alternatively may also describe arbitrary other EFI executables.

    • Unified kernel images following the Boot Loader Specification[1], as executable EFI binaries in /EFI/Linux/ on the ESP.

    • The Microsoft Windows EFI boot manager, if installed

    • The Apple MacOS X boot manager, if installed

    • The EFI Shell binary, if installed

    • A reboot into the UEFI firmware setup option, if supported by the firmware
    .PP kernel-install(8) may be used to copy kernel images onto the ESP and to generate description files compliant with the Boot Loader Specification. bootctl(1) may be used from a running system to locate the ESP, list available entries, and install systemd-boot itself.
    .PP systemd-boot will provide information about the time spent in UEFI firmware using the Boot Loader Interface[2]. This information can be displayed using systemd-analyze(1).

  .SH "KEY BINDINGS"

    .PP The following keys may be used in the boot menu:

      .PP ↑ (Up), ↓ (Down), j, k, PageUp, PageDown, Home, End

            Navigate up/down in the entry list
          .RE
          .PP ↵ (Enter)

                Boot selected entry
              .RE
              .PP d

                    Make selected entry the default
                  .RE
                  .PP e

                        Edit the kernel command line for selected entry
                      .RE
                      .PP +, t

                            Increase the timeout before default entry is booted
                          .RE
                          .PP -, T

                                Decrease the timeout
                              .RE
                              .PP v

                                    Show systemd-boot, UEFI, and firmware versions
                                  .RE
                                  .PP P

                                        Print status
                                      .RE
                                      .PP Q

                                            Quit
                                          .RE
                                          .PP h, ?

                                                Show a help screen
                                              .RE
                                              .PP Ctrl + l

                                                    Reprint the screen
                                                  .RE

                                                .PP The following keys may be used during bootup or in the boot menu to directly boot a specific entry:

                                                  .PP l

                                                        Linux
                                                      .RE
                                                      .PP w

                                                            Windows
                                                          .RE
                                                          .PP a

                                                                OS X
                                                              .RE
                                                              .PP s

                                                                    EFI shell
                                                                  .RE
                                                                  .PP 1, 2, 3, 4, 5, 6, 7, 8, 9

                                                                        Boot entry number 1 ... 9
                                                                      .RE

                                                                    .PP In the editor, most keys simply insert themselves, but the following keys may be used to perform additional actions:

                                                                      .PP ← (Left), → (Right), Home, End

                                                                            Navigate left/right
                                                                          .RE
                                                                          .PP Esc

                                                                                Abort the edit and quit the editor
                                                                              .RE
                                                                              .PP Ctrl + k

                                                                                    Clear the command line
                                                                                  .RE
                                                                                  .PP Ctrl + w, Alt + Backspace

                                                                                        Delete word backwards
                                                                                      .RE
                                                                                      .PP Alt + d

                                                                                            Delete word forwards
                                                                                          .RE
                                                                                          .PP ↵ (Enter)

                                                                                                Boot entry with the edited command line
                                                                                              .RE

                                                                                            .PP Note that unless configured otherwise in the UEFI firmware, systemd-boot will use the US keyboard layout, so key labels might not match for keys like +/-.

                                                                                          .SH "FILES"

                                                                                            .PP The files systemd-boot reads generally reside on the UEFI ESP which is usually mounted to /boot/, /efi/ or /boot/efi during OS runtime. systemd-boot reads runtime configuration such as the boot timeout and default entry from /loader/loader.conf on the ESP (in combination with data read from EFI variables). See loader.conf(5). Boot entry description files following the Boot Loader Specification[1] are read from /loader/entries/ on the ESP. Unified kernel boot entries following the Boot Loader Specification[1] are read from /EFI/Linux/ on the ESP.

                                                                                          .SH "SEE ALSO"

                                                                                            .PP bootctl(1), loader.conf(5), Boot Loader Specification[1], Boot Loader Interface[2]

NOTES

1.  Boot Loader Specification
    https://github.com/systemd/systemd/blob/master/doc/BOOT_LOADER_SPECIFICATION.md

2.  Boot Loader Interface
    https://www.freedesktop.org/wiki/Software/systemd/BootLoaderInterface