I'm trying to upgrade a Digital Ocean's ubuntu VM from 20.04.6 to 22.04.5 using do-release-upgrade. I'm connected through SSH.
Unfortunately, that's not direct and it's asking me to install all available updates before upgrading.
Before starting, I created a snapshot to quickly recover if anything goes wrong.
While following instructions from this forum, it suggests me to run sudo apt full-upgrade. After running it and rebooting, the machine refuses connection (which means it entered a state where it's not booting). It doesn't connect even from Digital Ocean's console inside their control panel, let alone through SSH.
After restoring the snapshot, I tried to follow the instructions in this post. After running sudo apt-get dist-upgrade, I got the same problem after rebooting.
Trying to run sudo do-release-upgrade without rebooting would download and install the upgrade, but the machine is rendered unbootable at the end anyway.
So, what am I missing here? Any hints?
[UPDATE]
I was able to install all required updates by running sudo apt list --upgradable and installing each one manually with the sudo apt-get install, while applying autoremove when necessary. Now my system is fully upgraded. But when running sudo do-release-upgrade, after finishing a long upgrade process, the system was rendered unbootable. I even tried shutting the droplet down and turning it on again, but got no success getting it online. I'll restore the snapshot and try investigating further.