I have a machine with a lot of partitions, and I've been trying and failing to create alternative root partitions with some variation in software. Don't ask why -- it's for a hobby that I'm doing and it's about as complicated as anything I did in my Comp Sci PhD work.
Two symptoms have emerged on two different partitions. I'm not sure if I should be asking them together, but they're similar enough for me to want to try this. All are Xubuntu 20.04 or 22.04. All use GRUB. All on the same 2TB SSD drive.
I don't want to start over, because I want to extract some information about packages before that happens.
Symptom 1: Boot seems to work, but when I check the output of lsblk(8) I see that root is not the partition that GRUB said it was booting. I've checked the UUIDs of the drives and of the root-directory line in /etc/fstab. All seems normal -- the root partition UUID in /etc/fstab matches the UUID of the drive it is on.
Symptom 2: Boot fails. Mixed in the messages on screen when the kernel panics, there's a mention that it cannot find it's root partition. Again, UUIDs seem normal.
I don't know what else to check. I've done an update of GRUB so I'd expect it's using the IDs I'm looking at.
