Why does systemctl isolate multi-user.target succeed only once?

Question

I was just taught here that systemctl isolate multi-user.target is the modern way to unload the graphic shell, which was done by init 3 previously.

I see that init 3 still works in my system but it succeeds only once, likewise systemctl. When you run them once, then, it is fine -- the Gnome/KDE is unloaded and you can startx again. But, once you did that, initializing to level 3 does not work anymore. I am left at level 5, in KDE, at least in my Fedora-24. systemctl just hangs until I kill it with Ctrl+C. Why is that? Do you notice the same behaviour?

Yes, I run the go to multi-user command from the GUI terminal.

Answer 1

You are in runlevel 5 or to be precise in graphical.target. You do runlevel 3 or systemctl isolate multiuser.target.

If you type startx you are still in runlevel 3 or multiuser.target, even if X is running, so systemctl isolate or runlevel 3 will not work.

Answer 2

From documentation, you can use set-default instead of isolate:

$ sudo systemctl set-default multi-user.target

Then reboot.