Process aborts when upgrading from 18.04 to 20.04
I tried to upgrade from 18.04 to 20.04 using the terminal and the process aborts without any information messages:
frepie@frepie-K55N:~$ sudo do-release-upgrade
Checking for a new Ubuntu release
Get:1 Upgrade tool signature [1,554 B]
Get:2 Upgrade tool [1,340 kB]
Fetched 1,342 kB in 0s (0 B/s)
authenticate 'focal.tar.gz' against 'focal.tar.gz.gpg'
extracting 'focal.tar.gz'
Reading cache
Checking package manager
Reading package lists... Done
Building dependency tree
Reading state information... Done
Hit http://ca.archive.ubuntu.com/ubuntu bionic InRelease
Get:1 http://ca.archive.ubuntu.com/ubuntu bionic-updates InRelease [88.7 kB]
Get:2 http://security.ubuntu.com/ubuntu bionic-security InRelease [88.7 kB]
Hit https://linux.teamviewer.com/deb stable InRelease
Get:3 http://ca.archive.ubuntu.com/ubuntu bionic-backports InRelease [74.6 kB]
Hit https://repo.skype.com/deb stable InRelease
Hit http://ppa.launchpad.net/alexlarsson/flatpak/ubuntu bionic InRelease
Hit https://packages.microsoft.com/repos/ms-teams stable InRelease
Hit http://ppa.launchpad.net/nixnote/nixnote2-stable/ubuntu bionic InRelease
Hit http://ppa.launchpad.net/obsproject/obs-studio/ubuntu bionic InRelease
Hit http://ppa.launchpad.net/team-xbmc/ppa/ubuntu bionic InRelease
Hit https://packagecloud.io/slacktechnologies/slack/debian jessie InRelease
Hit http://ppa.launchpad.net/tsbarnes/indicator-keylock/ubuntu bionic InRelease
Fetched 252 kB in 0s (0 B/s)
Reading package lists... Done
Building dependency tree
Reading state information... Done
Restoring original system state
Aborting
Reading package lists... Done
Building dependency tree
Reading state information... Done
frepie@frepie-K55N:~$
You cannot always upgrade to a new release when you have PPAs still enabled. You should only have the official sources before you start the upgrade process.
You also have sources that are for Debain and not Ubuntu. This can cause a lot of problems with your package management even in-between release upgrades.
It depends on how far the release upgrade proceeded. If this upgrade attempt failed halfway through, you may need to perform a clean installation. It can be difficult to release upgrade after a failed attempt. If you are not very proficient in solving potentially several issues due to the failed release upgrade, a clean installation will be much easier and more reliable.
If the release upgrade stopped at the very beginning, you should be able to proceed with the release upgrade after removing the offending sources.
To disable sources, first make a backup of your current list of sources:
sudo cp /etc/apt/sources.list /etc/apt/sources.list.bak
Then edit the sources.list:
sudo nano /etc/apt/sources.list
Comment out all sources that are not official Ubuntu sources by putting a # before each line. In your example above, you should comment every line that doesn't include ubuntu.com, so comment out all the PPA lines from launchpad.net as well as Skype, teamviewer, slack, Microsoft, etc.
When you are finished editing, press CTRL+O to save, then CTRL+X to exit.