On 16/02/2023 at 14:49, Chandler wrote:
Hi all, I recently (like a month ago) upgraded one of our computers that
hadn't received any upgrades for like 2 years. Afterwards, it wouldn't
boot.
What happened exactly at boot time ? Any error message ?
I think it was because Grub2 got upgraded and no longer supported MBR?
(it's now version 2.06-3~deb11u5)
I read something along those lines, that I had to be using GPT now. So
Nonsense. Of course GRUB still supports MBR/DOS.
Except! The boot menu is now gone and I actually just noticed now
that I'm trying to run memtest86. I tried holding Shift while it
tries to boot, and also have tried tapping Esc, but neither of these
bring up the menu.
What is in /etc/default/grub ?
Then I remembered I could use grub-reboot to boot into memtest86, but
not on this system apparently because when I tried that it told me this:
WARNING: Detected GRUB environment block on diskfilter device
Memory test (memtest86+, serial console 115200) will remain the default
boot entry until manually cleared with:
grub-editenv /boot/grub/grubenv unset next_entry
I guess, it's because /boot is on a md device?
See grub-reboot manual. GRUB cannot write on RAID or LVM devices at boot
time to remove the next boot option in the GRUB environment block
/boot/grub/grubenv, so the option will be persistent.
