Update from 18.04 the Debian way right now

[kilgoretrout]

Here's the article posted without warranty of any kind. Don't attempt this without doing a full backup first from which you can do a bare metal restore:

https://dbaxps.blogspot.com/2020/04/...-2004-lts.html

Basically, you're editing your /etc/apt/sources.list replacing each instance of bionic with focal which is pretty much the Debian way of doing things. It worked for me but not without a few bumps in the road, several:

$sudo apt --fix-broken install

and several reboots. This is definitely not recommended for beginners.

[claydoh]

No, it is not recommended by anyone

The upgrade tool does more than just switch repos. Disabling PPAs, accounting for any quirks that are known, etc.

Why would one rely on Joe Random Blog, when there is a better, official method:

sudo do-release-upgrade -c -d

[kilgoretrout]

Here's why:

sudo do-release-upgrade -c -d
Checking for a new Ubuntu release
New release '20.04' available.
Run 'do-release-upgrade' to upgrade to it.
$ sudo do-release-upgrade
Checking for a new Ubuntu release
There is no development version of an LTS available.
To upgrade to the latest non-LTS develoment release 
set Prompt=normal in /etc/update-manager/release-upgrades.

And it won't be available until sometime in July when 20.04.1 is released. If you want to upgrade now from 18.04 to 20.04 the above way can work if you know what your doing and are prepared to do a little cleanup. I've done it twice without too much trouble but I would never try it without a good backup and I would never recommend it for beginners. YMMV

[claydoh]

ahhh I dunno why I left the '-c' in there. That is used to check, without any further actions.

leave it out, and try it again

[kilgoretrout]

Thanks. That now works. I was under the impression that you had to wait until the .1 release when upgrading between *buntu lts versions. Apparently, that's not the case. I've always found OS upgrades to be problematic no matter what the OS and always do a full backup before trying.

The Debian way is pretty straightforward - you disable third party repos; possibly remove any third party deb packages; edit your sources per the above article; cross your fingers, pay homage to a higher authority and let her fly. That works well with Debian stable and I was curious to try it out with kubuntu. After wading through several apt error messages and fixing things the Debian way worked perfectly on my laptop for kubuntu.

Tried the way you suggested on one of my desktop PCs. The ubuntu upgrade tool worked well without throwing out a bunch of error messages which greatly simplified the process. The resulting 20.04 installation was stable except for some windows games, one of which wouldn't launch and one of which launched with no sound. I assume some needed 32 bit libraries were probably removed during the upgrade. Didn't bother to further troubleshoot and restored 18.04 from my backup. I will probably try to do a clean install on the desktop at a later date. Not a lot else to do these days.

[jglen490]

Clean install. Simple. Predictable.