Upgraded to 24.04 and is no longer booting

Support and Help
1

Hello

Ubuntu Version:
22.04 LTS upgrad(ed/ing) to 24.04.1 LTS

Desktop Environment (if applicable):
Gnome (standard version)

Problem Description:
My system started off with Windows but I removed it and installed Ubuntu 20.04, all zfs (seemed like a good idea at the time but makes things more complicated when there are problems during upgrades). After putting it off I decided to accept the prompt to upgrade from 22.04 to 24.04. After upgrade was complete rebooting the system came up with a blank screen that rebooted to BIOS. Using the BIOS boot menu I could start the upgraded Ubuntu system but I wanted to fix this booting problem. Found the boot-repair boot disk, ran the recommended repair and now the boot from bios no longer works. As I was frequently in the BIOS screen saw that there was a newer version, so installed it. Now when I run the boot-repair system scan it doesn’t complete (at least not within an hour or 2). Looking at the BIOS screen I see that the UEFI compatibility setting are now turned off. Turing them on at least allows completion the boot-repair scan in under 5 min. I looked at the advanced options of the boot-repair but never clicked on apply, although while selecting options it appeared that the program went ahead to apply the modification (or the program just crashed) which concerned me. In the end it didn’t appear to change things much. Also many of the advanced options are not even available when I look at them (GRUB location and GRUB options where grayed out, while MBR options were available at first but even that became greyed out later).
So now I am looking to repair this system preferably without reinstalling Ubuntu. I am guessing that I need to reinstall the gub2 bootloader (?) but how and where? The mbr the bpool partition? I have posted the a few system scans from boot-repair. The first one I believe is before the recommended repair. The last one is from today. Any help suggestions would be greatly appreciated.

https://pastebin.com/zaJAJmcS
https://pastebin.com/tBmJyDfw

Relevant System Information:
see pastebin

What I’ve Tried:

2

Welcome to Ubuntu Discourse @stiphy
Did you reinstall Ubuntu 24.04 as a .2 release afterwards?

I’ve never went to that issues when I’ve updated 24.04 to 24.04.1 or 24.04.2 back in Feb 11 of this year.

3

For the moment I’m trying to avoid reinstalling, I want to keep some the software with their settings. Or do you mean reinstalling over the current system?

4

You could always backup your data before reinstalling Ubuntu, I’ve done that a lot.

5 
/efi/BOOT/fbx64.efi

looks like your boot files on sda1 are in the completely wrong location … the above should be /boot/efi/...

6

You show both BIOS boot using MBR and UEFI boot using ESP - efi system partition, your sda1.
MBR has the sysLinux boot loader. Syslinux is often used as an alternative to the Windows BIOS mode boot loader as it then loads more boot code from partition PBR. Not sure if ZFS even has that?

You also show the very old MBR partitioning. The only place for MBR, now is for those that must boot Windows in old BIOS mode as that required MBR. Microsoft has required UEFI with gpt partitioning since 2012. Laptops starting in 2020 became UEFI only. My Dell says BIOS, but in “BIOS” is says UEFI boot only. While best to convert to gpt, that will totally erase drive, so good backups required. So just plan on that conversion with the next full install, and then restore from backup.

Looks like system may have been UEFI boot. But Boot-Repair is not showing fstab (since zfs?) which would show mount of esp, if UEFI boot. Since it looks like Boot-Repair cannot see fstab and other files inside your zfs, you cannot use it to reinstall grub.

You have to do a full chroot. I do not know zfs and what extra commands in chroot may be required to mount those partition(s). While ubuntu forum is closed, you can still read it. This is a linke to discussion of chroot & zfs.

Make sure UEFI/BIOS is set to boot in UEFI boot mode. Some may need UEFI only, not a setting for both.