Question about BIOS Access

[disp6252]

@quantum

After clearing the BIOS to regain BIOS access I can no longer boot into Qubes (drive not shown). Is it possible to clear the BIOS and regain access to my Qubes system without having to reload Qubes?

You can restore EFI entry like this:

Qubes Drive Not Bootable after removal / reinsertion

I don’t think the boot sector has been deleted (since it’s on the drive that you removed) – I believe the EFI entry has been deleted from the BIOS – I’ve seen this happen on my laptop. I think the computer boots and notice the missing drive/EFI Entry and then removes the entry from the menu. To add it back to the BIOS/UEFI, you should be able to do: efibootmgr -c -d /dev/nvme0n1 -p 1 -L "QUBES" -l '\EFI\qubes\grubx64.efi' from the USB stick.

You can also use EFI fallback bootloader path EFI\boot\bootx64.efi so you’ll no longer have to restore EFI entry in the future

Install whole system to an external SSD

I think you can use UEFI fallback bootloader path EFI\boot\bootx64.efi: By copying files from qubes to boot directory and renaming them.

Copy files from /boot/efi/EFI/qubes to /boot/efi/EFI/BOOT and in /boot/efi/EFI/BOOT change filenames grubx64.efi → BOOTX64.efi and grub.cfg → BOOTX64.cfg