Bug#1034812: Unbootable after install: UEFI installed to wrong ESP
I had a similar problem with my customized Debian 10 installer. I have not customized PARTMAN related UDEB packages yet, so these are at Debian 10 versions. What I did was I installed my Debian in one of my test laptops that also had another SSD with some Windows 11 installation that I plan to nuke later:). All was working and booting, but when I added ESP capacity monitoring to my CONKY configurations, I noticed that this laptop had different ESP space occupied than my other laptops with the same hardware. After checking what is going on I found that:
- The ESP created by me during manual disk partitioning on the SSD that is used for my Debian system was empty and not used at all (not mounted at "/boot/efi" and not mentioned in "/etc/fstab").
- Instead the ESP from the other SSD with the Windows 11 installation was used. It was mounted at "/boot/efi", its UUID was in "/etc/fstab" and DI/GRUB installed the "EFI/debian/grubx64.efi" file there right next to the "Microsoft" and "Boot" directories that contained the Windows garbage.
Thankfully I did not boot that Windows 11 installation, so Windows were not able to mess around with the Debian files that rudely appeared on "their" disk. I was able to (hopefully) fix the situation when I noticed it:
- I archived "/boot/efi/EFI/debian/grubx64.efi" from "/dev/sda1" to "/Archive.tar".
- Then, I unmounted "/dev/sda1" from "/boot/efi" and mounted "/dev/sdb1" to "/boot/efi" and extracted "/Archive.tar" in "/boot/efi" again.
- Later I changed UUID of ESP in "/etc/fstab" file to that of ESP on "/dev/sdb1".
- Finally using EFIBOOTMGR I deleted the EFI boot entry my system used and created a new entry for ESP on "/dev/sdb1".
- Then, I tested that the system boots as before using the new EFI and FSTAB entries and correct ESP.
Did I forget something (that will cause problems in the future) by not reinstalling GRUB or some other stuff?
Do the fixes mentioned above also address the manual partitioning case? If not perhaps you could check that case also. I will keep the Windows 11 installation (as this laptop is for testing anyway) = if you want I could test the fixed PARTMAN files, if these are provided so that my script for customizing the Debian Netinst ISO can include them (after I modify it to extract a new PARTMAN TAR or copy new PARTMAN files directly to the extracted Debian Netinst ISO). (In the future I plan to learn how to create DI ISO from scratch to be able to include modified UDEB packages etc. => if that is needed for testing and you can provide some starting instructions for me I could try that also.)
Regards,
Jmkr
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