[SOLVED] Peculiarity installing LM18 in Vbox+EFI

[MikeF90000]

I've never had issues installing LM in Virtualbox 5.1.34 in the default 'BIOS' mode on a virtual disk with a DOS partition table.

I decided to familiarize myself with EFI installs, so I set up a VM in EFI mode with a GPT virtual disk.
Installation proceeded with no issues, but upon reboot I got the EFI shell:


Anyone else had this happen, and what might be the cause?
TIA, Mike

[catweazel]

Virtualbox 5.1.34

Download and install a newer version from Oracle, including the extension pack.

[fabien85]

Well if you *really* want to learn EFI, you could start mastering the EFI shell. (however it's 99% sure you will never need this knowledge in any practical situation)

A list of EFI shell commands is given here and there, and you can get more details from the shell with help command, with the -b option being usefull to limit the output to one screen at once, e.g. help bcfg -b
From the shell you can see what's the content of the NVRAM. e.g. to see the stored boot entries :

Code: Select all

bcfg boot dump

fs0 is the EFI partition. If the Mint installed went well, the bootloader is installed there at EFI/ubuntu/grubx64.efi
So you can launch grub from the shell with the following commands

Code: Select all

fs0:
cd EFI/ubuntu
grubx64.efi

In fact you could even directly boot the kernel, if it was on a partition readable by the EFI shell. That's not what happens on a default Mint install, but it's possible if you put the kernel (and initrd image etc) on a fat32 partition, or if you attach an EFI driver for the linux filesystem (typically ext4), which is e.g. what refind is doing.

[MikeF90000]

Just got a chance to revisit this issue. Unfortunately, my latest install did not complete - error "grub-efi-amd64-signed" package failed to install into /target. FYI the /target partition is only 50% full. Hmmm, sounds like another grub related issue.

I rebooted using Super Grub Disk 2 (which found the kernel) and then ran grub-install and update-grub. Lo and behold, the VM now boots up successfully.

[fabien85]

The first version of the Mint 19 ISO had this grub problem, so that's probably what you hit. Workaround is either to use the v2 (simplest and recommended way), or find a way to repair grub (boot-repair, chroot, supergrub2/refind+grub-install...).

Once you have a running OS, whether the boot mode is Legacy or EFI does not make much difference.

[kukamuumuka]

You need to copy SuperGrub2 image using dd to the first partition, so SG2 boots EFI up.
https://puolanka.info/goto/uefi-boot-wi ... partition/

[MikeF90000]

The first version of the Mint 19 ISO had this grub problem, so that's probably what you hit. Workaround is either to use the v2 (simplest and recommended way), or find a way to repair grub (boot-repair, chroot, supergrub2/refind+grub-install...).

Thanks much for the info, not sure how I missed this ....
Regarding EFI, the Rod's Books site is well worth a read.