To remove "E: No priority (or zero) specified for pin" message you have to remove the Ubuntu Advantage (UA) ESM files by
sudo rm /etc/apt/preferences.d/ubuntu-esm-infra
sudo rm /etc/apt/sources.list.d/ubuntu-esm-infra.list
as Ubuntu 18.04 LTS is supported release, so no UA ESM is really needed here.
Then check that you have correct lines in the /...
For me, the reason to cause this problem is that I have additional python distribution installed on my computer /usr/local/bin/python3, which comes before /usr/bin/python3 in the search path. I modified manually the post-installation and pre-remove script in /var/lib/dpkg/info/ubuntu-advantage-tools.postinst and /var/lib/dpkg/info/ubuntu-advantage-tools....
I got similar problem and this worked for me:
Removing the uat, process will not complete, maybe missing uaclient.apt
sudo apt-get remove ubuntu-advantage-tools
Then manually remove the uat by:
sudo mv /var/lib/dpkg/info/ubuntu-advantage-tools.* /tmp/
sudo dpkg --force-remove-reinstreq --purge ubuntu-advantage-tools
sudo dpkg --remove --force-remove-...
I had the problem that sudo apt update failed and thus I was not able to proceed to do-release-upgrade ( I got stuck on Please install all available updates for your release before upgrading..)
I was able to fix most problem using the suggestion provided here and removing some packages (in my case skypeforlinux).
Later I also encountered the problem that ...
I would guess your hardware does not have an IPMI chip. To simply stop the errors during boot
systemctl disable openipmi
An LSB service is not defined natively in systemd. That reduces the info that systemd can tell you. In this case, openipmi installs the script /etc/init.d/openipmi. It looks like this script has some built-in options to provide info. ...