How to upgrade from 18.10 to 20.x?

[cteno]

I have Lubuntu 18.10, and would like to move to a supported version for obvious reasons. I have followed the instructions here and the update && full-upgrade went without a problem. However, running do-release-upgrade results in the message “An upgrade from ‘cosmic’ to ‘focal’ is not supported with this tool.”

I found a support topic elsewhere that suggested I try changing the value in /etc/update-manager/release-upgrades to ‘normal’ and that this would result in do-release-upgrade upgrading to 19.04 as opposed to the latest supported release. However, this value was already ‘normal’ on my system.

I would be fine with upgrading to 19.04 if that’s the only possibility; honestly, I just want to be able to download… well, anything. I’m fairly inexperienced with linux. I made a bootable USB last year, thinking that I was thinking ahead, but shows what I know :). I appreciate in advance any advice you can give.

PS: I see that having a supported version of lubuntu is one of the rules for posting a support question. Please excuse my not following that order of operations.

[guiverc]

Lubuntu 18.10 was a standard release, which came out in 2018-October (thus 18.10 using the year.month format used by Ubuntu and flavors), with a supported-life of 9 months. The Lubuntu team tested it to upgrade to the next release, or Lubuntu 19.04 (or the 2019-April release).

Lubuntu 19.04 was likewise tested to upgrade to it’s next release, ie. 19.10 (2019-October release). All those releases (18.10, 19.04 & 19.10) are now EOL or end-of-life. Lubuntu 19.10 could upgrade though to Lubuntu 20.04 LTS.

Upgrades are tested and known to work when a release is supported. However after a release goes EOL, the repository will get moved (see EOLUpgrades - Community Help Wiki) meaning eventually the tools won’t see the software anymore as it’s no longer where they look. To avoid this the release-upgrade should occur during the supported life of the product, OR very soon after.

What can you do?

Firstly have you changed your software sources so the cosmic (18.10) software can be found, to ensure your system was fully-upgraded? If you’re fully upgraded (18.10/cosmic wise) you’ve more chance of it working, but it still won’t go to 19.04 (it’s EOL) and skipping releases (ie. 18.10 to 20.04) isn’t recommended.

The next alternative is to

1. backup all your data & software
2. write a Lubuntu 20.04 LTS ISO to media, and install the new system. I’d use Manual Partitioning, selecting your existing partition(s), and ensure you don’t have format ticked.

This is FAR faster and will skip the missed releases. If you don’t format, it’ll note your added packages, wipe system directories, install, add back your additional packages (if available in your new 20.04 release) then ask to reboot. It won’t erase data unless you had ‘format’ checked, but as that’s easily missed, ensure you’ve backed up your data anyway.

–
In case you missed the EOL upgrades detail, a supported Ubuntu release can be found at

http://archive.ubuntu.com/

but after EOL, it gets moved to

http://old-releases.ubuntu.com/

Also note: There can be country codes for the main archive, eg. as an Aussie, I could be using http://au.archive.ubuntu.com/ , however there are no country codes for old-releases, so the au. for me would need removing. I’d use the link I provided firstly. I’ve also assumed your architecture is amd64, if you’re using i386 you should return to Lubuntu 18.04 LTS via re-install.