When I try to run one of these commands:
sudo service gdm restart
sudo service gdm3 restart
the system gets stuck in a loop. It goes from the graphical interface to a black screen, then a terminal-like screen with lots of [ OK ]
and then again GUI, this repeats cca every second.
It is impossible to stop this, as GUI ceases to respond to any keystrokes and tty
randomly misses some of them (so that it's not possible to correctly input the password).
What is the correct procedure for restarting X then?
(I'm on a freshly installed Ubuntu 18.04 on Acer A315)
gdm may be buggy.
As a workaround, I use lightdm.
Choose lightdm as the display manager. And X restart works.
Go Ctrl-Alt-F6 to get a tty;
then follow @Vajira Prabuddhaka at: GDM3 does not start in Ubuntu 18.04
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