This sounds like a rather obscure title, don't you think? Well, picture this. You have an Ubuntu distro flavor installed, in my case Kubuntu 18.04 Beaver or KDE neon, and you want to reboot. For some odd reason, clicking the right button through the system menu does not do anything. There's no restart happening. OK, so you go for a command line trick.

You open a console window and you type sudo reboot. Only you receive the following error message: Failed to start reboot.target: Transaction is destructive. See system logs and 'systemctl status reboot.target' for details. What. At this point, it seems like a hard boot is the only option. But then, that's not really a solution. Let's investigate.