Here is a quick tip to kill a crashed Linux / UNIX X desktop system. Many new user do not know this simple tip and end up hitting computer reboot button. Press CTRL + ALT + Backspace to kill GUI and get back to login screen. There are more ways to kill a crashed desktop without restarting your computer.
Linux, Mac OS X, Vista and XP: head-to-head – Operating systems at war – but who wins?
It is true that connections to remote X Window servers should be always made over SSH. SSH supports X windows connections. So my task was allow X over ssh but block unprivileged X windows mangers TCP ports.
The first running server (or display) use TCP port 6000. Next server will use 6001 and so on upto [...]