Just upgraded today from 16.04 to 18.04 and I got the same issue. The systemd-shim package was still installed, the only way I had to uninstall it was to force remove systemd, then I was able to purge systemd-shim and reinstall systemd
I made sure that xenial was up2date before starting the update (using update-manager) to bionic -- You received this bug notification because you are a member of Ubuntu Bugs, which is subscribed to Ubuntu. https://bugs.launchpad.net/bugs/1773859 Title: upgrades to 18.04 fail To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/systemd/+bug/1773859/+subscriptions -- ubuntu-bugs mailing list ubuntu-bugs@lists.ubuntu.com https://lists.ubuntu.com/mailman/listinfo/ubuntu-bugs
