I Upgrade 20.10 to 21.04 from a running system. The upgrade seemed to go OK. It complained about PHP's config file -- This was reasonable since I had made some changes. Etc.
Finally, it rebooted, but never came back to life. Various attempts to boot include:
F2 Enter Setup: Big menu; everything looked OK. Then
GNU GRUB version 2.04
*Ubuntu
Advanced options for Ubuntu
UEFI firmware settings
The UEFI option just leads back to the logo screen. Either of the first two options leads to several pairs of these (with diff numbers for xx and yy):
Ubuntu, with Linux 5.xx.0.yy-generic
Ubuntu, with Linux 5.xx.0.yy-generic (recovery mode)
"e" leads to a config file headed with
setparams "advanced option for Ubuntu"
From there I can get to a "grub >" prompt. (But I have no idea what to do then.)
Any of the Ubuntu lines leads to a screen like
Loading linux 5.11.0-41-generic ...
Loadng initial ramdisk ...
Then it sits there for many minutes (until I give up). (I'm used to the entire boot taking a minute or so.)
Based on numerous forum tips, I built a Live USB ISO. Then discovered nothing "wrong":
- I used
fsck
to check each filesystem -- no changes needed
- All files seemed to be intact.
The filesystems (none are even close to full):
nvme0n1p1 - /boot/EFI 285MB EFI partition (EFI system)
nvme0n1p2 - /boot 2.3G (Linux filesystem)
nvme0n1p3 - / 1.8T (rootmou partition)
F10 Enter boot menu:
(multiple ethernet options)
OS on hard drive (Samsung...2TB)
ubuntu (Samsung...2TB)
I picked only the last one; (I don't think there is another "OS on hard drive".)
Any suggestions of what to try next?