Prompts to Enter Grub Commands

[martinjdz]

I upgraded from 22.04 to 24.04 several months ago. The PC was very sluggish. I decided to re-install 22.04. I used the same GPT partitions (Home, Swap, and Root). I reformatted each one, giving each one the same mount points. The system was supposed to put the boot command on Sda, (I'm not exactly sure whether that is at the beginning of the hard drive or on the root partition. Home is Sda2. Root is Sda4.)

The installation completed. When I restarted, I was stopped by the following message on the screen:
Gnu Grub Version 2.12
Minimal Bash-like editing is supported. For the first word, TAB lists possible command completions. . . .

There was a type-in command line field preceded by Grub>

It seems impossible to exit from this prompt. I can't do anything to get beyond it and complete the startup.

I can't figure out how Grub 2.1 became involved in this installation process. It seems that something is stored at the beginning of the hard drive--- perhaps something left over from 22.04-- and it is causing problems.

Any suggestions? I really don't want to have to blank the whole drive, re-create the GPT partition, and start over again.

[jlittle]

... I decided to re-install 22.04...

I presume you used a USB stick that had the 22.04 iso written to it. When you booted the USB stick, were you careful to choose the UEFI option? Your report reads like you performed a BIOS/MBR install. Once the stick has booted using BIOS mode, one can only do a BIOS MBR install.

[martinjdz]

Everything I have and use is UEFI, GPT. However, it is possible that on 22.04, I installed the Grub 2.0 editor. I thought that it might have some features that can be used to view UEFI boot instructions. I later uninstalled it--- long before upgrading. I am wondering whether this is part of the problem?

[claydoh]

. I used the same GPT partitions (Home, Swap, and Root)

What about the EFI partition?

[martinjdz]

Problem Fixed !

I did the whole install again. This time, I also reformatted the small FAT32 sector at the beginning of the drive, which I believe is called the Boot Sector. (The GPT partition begins right after it.)

The install completed just fine, and I am now back in business.

It seems that the problem had to do with old information in the Boot Sector. Reformatting that region eliminated the problem.

[jlittle]

It seems that the problem had to do with old information in the Boot Sector.

UEFI should not pay any attention to the old MBR boot sector. It looks in NVRAM for the entry in the ESP to boot.

Perhaps your firmware has a legacy boot option enabled?