GRUB/EFI examples

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Tango-inaccurate.pngThe factual accuracy of this article or section is disputed.Tango-inaccurate.png

Reason: Many of the examples below indicate that the GRUB EFI binary (grubx64.efi) needs to be copied to a special location (e.g, esp/EFI/BOOT/bootx64.efi). Although this may work, this is the fallback filename. Other options may also work, like using efibootmgr or UEFI shell. (Discuss in Talk:GRUB/EFI examples#)

It is well known that different motherboard manufactures implement UEFI differently. The purpose of this page is to show hardware-specific methods known to work when installing/restoring GRUB in EFI mode.

Note: In the entire article esp denotes the mountpoint of the EFI system partition aka ESP.

Apple Macs

Use bless command from within macOS to set grubx64.efi as the default boot option. You can also boot from the macOS install disc and launch a Terminal there if you only have Linux installed. In the Terminal, create a directory and mount the EFI system partition:

# cd /Volumes
# mkdir efi
# mount -t msdos /dev/disk0s1 /Volumes/efi

Then run bless on grub.efi and on the EFI system partition to set them as the default boot options.

# bless --folder=/Volumes/efi --file=/Volumes/efi/EFI/GRUB/grubx64.efi --setBoot
# bless --mount=/Volumes/efi --file=/Volumes/efi/EFI/GRUB/grubx64.efi --setBoot

More info at https://help.ubuntu.com/community/UEFIBooting#Apple_Mac_EFI_systems_.28both_EFI_architecture.29.

Note:

Asus

Z68 Family and U47 Family

# cp esp/EFI/GRUB/grubx64.efi esp/shellx64.efi

After this launch the UEFI Shell from the UEFI setup/menu (in ASUS UEFI BIOS, switch to advanced mode, press Exit in the top right corner and choose "Launch EFI shell from filesystem device"). The GRUB menu will show up and you can boot into your system. Afterwards you can use efibootmgr to setup a menu entry, for example if you have the EFI system partition on /dev/sda1:

# efibootmgr --create --disk /dev/sda --part 1 --write-signature --loader /EFI/GRUB/grubx64.efi --label "GRUB" --verbose

If your motherboard has no such option (or even if it does), you can use UEFI shell to create a UEFI boot option for the Arch partition temporarily.

Once you boot into the UEFI shell, add a UEFI boot menu entry:

Shell> bcfg boot add 0 FS0:\EFI\GRUB\grubx64.efi "GRUB"

where FS0: is the mapping corresponding to the EFI system partition and \EFI\GRUB\grubx64.efi is the the from the --bootloader-id from the grub-install command above.

This will temporarily add a UEFI boot option for the next boot to get into Arch. Once in Arch, modprobe efivars and confirm that efibootmgr creates no errors (no errors meaning you successfully booted in UEFI mode). Then GRUB installation can be performed again and should successfully permanently add a boot entry in the UEFI menu.

ux32vd

Note: The BIOS does not allow computer to boot from GPT disk if there is no properly set-up UEFI boot entry. The disk even may not be seen in BIOS in this case. The fix is to make a proper UEFI boot entry.

There is a caveat. If the machine was booted from MBR then grub-install (or efibootmgr) will fail to create the UEFI boot entry with the following error:

EFI variables are not supported on this system

You first need to boot the machine with EFI and then create the boot entry. This can be done the way described for Z68 Family: by copying esp/EFI/GRUB/grubx64.efi into esp/shellx64.efi and selecting "Launch EFI shell from filesystem device". After successful boot it is possible to create a boot entry using grub-install or efibootmgr.

P8Z77 Family

Tango-inaccurate.pngThe factual accuracy of this article or section is disputed.Tango-inaccurate.png

Reason: This procedure is most likely no longer necessary and you can just create the entry via efibootmgr. (Discuss in Talk:GRUB/EFI examples#)
Install GRUB and copy the modified UEFI Shell binary to ESP.

The EFI system partition should contain just two files:

/Shell.efi
/EFI/GRUB/grubx64.efi

Within UEFI shell

Shell> bcfg boot dump -v
Shell> bcfg boot add 1 FS0:\EFI\GRUB\grubx64.efi "GRUB"
Shell> exit
  • Reboot the machine and enter the BIOS.
  • Navigate to the Boot section and adjust the boot order to with the "GRUB" being the one on the SSD.
  • Boot to this entry and enjoy.

M5A97

Finish the standard Arch install procedures, making sure that you partition your boot hard disk as GPT.

Install GRUB and copy the modified UEFI Shell binary to ESP.

The reason that we need this shell application is that the efibootmgr command will fail silently during grub-install.

After this launch the UEFI Shell from the UEFI setup/menu (in ASUS UEFI BIOS, switch to advanced mode, press Exit in the top right corner and choose "Launch EFI shell from filesystem device"). The UEFI shell will show up. From here we need to add our GRUB entry to the NVRAM.

Shell> bcfg boot add 3 FS0:\EFI\GRUB\grubx64.efi "GRUB"

where FS0: is the mapping corresponding to the EFI system partition and 3 is the zero based boot entry index.

Tip: UEFI Shell commands usually support -b option which makes output pause after each page. map lists recognized filesystems (fs0, ...) and data storage devices (blk0, ...). Run help -b to list available commands. See Unified Extensible Firmware Interface#Important UEFI Shell commands for more information.

To list the current boot entries you can run:

Shell> bcfg boot dump -v

Asrock

Z97M Pro4

Tango-inaccurate.pngThe factual accuracy of this article or section is disputed.Tango-inaccurate.png

Reason: If efibootmgr works when launched from the installed system, why would it not work when grub-install executes it? (Discuss in Talk:GRUB/EFI examples#)

This is a similar procedure to Asus Z68 Family. This was tested on a Z97M Pro4 BIOS P1.90.

# cp esp/EFI/GRUB/grubx64.efi esp/shellx64.efi

After this launch the UEFI Shell from the UEFI setup/menu (in ASROCK UEFI BIOS, goto Exit tab and choose "Launch EFI Shell From Filesystem Device"). The GRUB menu will show up and you can boot into your system. Afterwards you can use efibootmgr to setup a menu entry, for example if you have the EFI system partition on /dev/sda1:

# efibootmgr --create --disk /dev/sda --part 1 --write-signature --loader /EFI/GRUB/grubx64.efi --label "GRUB" --verbose

Dell

PowerEdge T30

The Dell UEFI implementation needs the UEFI firmware workaround to load grub. Otherwise it will drop into a "no OS found" screen.

MSI

These MSI motherboards seem to want the EFI program to exist in a different location from where GRUB installs it. Do one of the following after following the instructions for installing GRUB:

B250M PRO-VH

# mkdir esp/EFI/BOOT
# cp esp/EFI/grub/grubx64.efi esp/EFI/BOOT/shellx64.efi

B250 PC MATE / H110I PRO

Install GRUB to the default/fallback boot path.

Note: The procedures above probably also work for other MSI motherboards.

HP

EliteBook 840 G1

See HP EliteBook 840 G1#UEFI Setup for details.

Note: The procedures in the link above probably also work for a range of other HP models.

Intel

S5400 Family

Tango-view-fullscreen.pngThis article or section needs expansion.Tango-view-fullscreen.png

Reason: Does it support booting from the default/fallback boot path esp/EFI/BOOT/BOOTia32.efi? If it does, the instructions could be simplified. (Discuss in Talk:GRUB/EFI examples#)

This board can run in BIOS or in EFI mode. BIOS mode requires an MBR partitioned hard drive, EFI - a GPT hard drive. Please note that this board operates on the Intel EFI v1.10 specification, and is IA32 (32-bit) only. The normal procedure for UEFI installation can be followed, with the exception of the following changes.

  • Instead of using the grub-efi-x86_64 target, grub-efi-i386 has to be used
  • The bcfg command is not available for pre-UEFI (v2.0) firmware. A startup.nsh file can be used on the root of the EFI system partition containing the path to the bootloader. For example: FS0:\EFI\GRUB\grubia32.efi has to be placed in the startup.nsh file on the root of the EFI system partition.
  • The grub.cfg file has to be placed in the same directory as the grub EFI binary, otherwise GRUB will not find it and enter the interactive shell.

Lenovo

K450 IdeaCentre

The EFI system partition requires the file \EFI\BOOT\BOOTx64.efi to be present in order to boot, otherwise you will receive "Error 1962: No operating system found. Boot sequence will automatically repeat."

Install GRUB to the default/fallback boot path.

This is a workaround for what is likely a bug in the UEFI implementation.

M92p ThinkCentre

This system whitelists UEFI boot entries. It will only boot from a entry called "Red Hat Enterprise Linux". So specify the bootloader-id appropriately:

# grub-install --target=x86_64-efi --efi-directory=esp --bootloader-id="Red Hat Enterprise Linux" --recheck --debug

X270 Thinkpad

Tango-inaccurate.pngThe factual accuracy of this article or section is disputed.Tango-inaccurate.png

Reason: There's no need to do anything special for UEFI booting on this laptop. (Discuss in Talk:GRUB/EFI examples#X270)

Install GRUB to the default/fallback boot path.