After upgrade from 42.3 to 15 stuck on grub rescue

Hi!

I have a ASUS SonicMaster with a dual boot primary with grub2 openSUSE and secondary Ubuntu 18.04.

Yesterday I made an upgrade from openSUSE LEAP 42.3 to LEAP 15 following the standard procedure as described in https://en.opensuse.org/SDB:System_upgrade.

I made a reboot after the upgrade yesterday and I saw the desktop looked a little funny as if not all services did start up. I left work and today when I return and start the computer I’m stuck on minimal grub and if I exit that one I fall over into grub rescue.

In grub rescue it throws the following errors:

error: file /boot/grub2/x86_64-efi' not found. error: file /boot/grub2/x86_64-efi/normal.mod’ not found.
Entering rescue mode…

After that I get the prompt:

**grub rescue>

**I have found out that grub are installed in ‘(hd0, gpt3)/boot/’

However if i run:

grub rescue> ls (hd0, gpt3)/boot/

… it gives me …

error: couldn’t find the chunk descriptor

Is there anyway to repair this situation?

/Paul

Those have to do with UEFI booting. You don’t need them if you are using legacy BIOS booting. You do need them if you are using UEFI booting.

I don’t know how you have been booting the system in the past.

My best guess is that you were using legacy BIOS booting when you did that upgrade with “zypper”. And, because of that, the files needed for UEFI booting were not upgraded.

That’s my tentative diagnosis of what went wrong. But you want to know how to fix it.

First question: Can you access the system – either booting from rescue media or via your Ubuntu install?

And how have you normally booted in the past – with legacy BIOS booting or with UEFI booting?