Tweetegy On the edge of chaos with Ruby, Rails, JavaScript and AngularJS.

| About | Search | Archive | Github | RSS |

Restart Ubuntu GUI without restarting Ubuntu

Here is a little trick I learned recently from Tropical Ice Cube. I am fairly new to Ubuntu and so all of what I heard was very new to me. So here is how you can “get out” of the graphical user interface, and restart it without having to reboot your machine.

To start off with, press CTRL+ALT+F2 At this point your entire screen will become a terminal window, so to speak. Note: You can go back to your GUI by pressing: ALT+F7

Now, back in the terminal, you can find the Ubuntu GUI process by running the following command. Note: once you see the results, you might want to scroll up or down the screen, in which case you can hold SHIFT and page-up or page-down keys to do that.

ps -A

Look for the process Xorg and gdm in the list – these are running the GUI. Of couse, you can also pipe the output of ps -A to grep to filter out Xorg and gdm processes as follows:

ps -A | grep Xorg
ps -A | grep gdm

You will probably notice that the output for Xorg is something like below. Note entry tty7. This stands for teletype7 and harks back to the old unix days. For more information about tty, see Ubuntu Forums post on tty and pty.. You’ll see that It is no coincidence that CTLT+ALT+F7 brings you back to the GUI!

2899 tty7     00:59:39 Xorg

Now run the killall command which terminates the specific processes as well as their children:

killall Xorg gdm

If you hit ALT+F7 now, there is no GUI! Where has it gone? Well you killed that process and in order to start it up again, run the following in the terminal:

sudo gdm

This will launch the GUI and take you back to the Ubuntu login screen. You will have to open all your GUI based applications again, of course. One thing also to note is that the GUI might start on a different tty. To check this type the following command in the terminal:

who

In my case, I see the following output. This tells me that there are two tty sessions running; one on tty2 (which is the terminal application I just used to restart gdm) and tty9 which is where the new gdm instance started. So now this basically means to get back to the GUI I need to hit CTRL+ALT+F9.

darren tty2         2009-09-17 10:29
darren tty9         2009-09-17 10:50 (:0)