Upgrade Ubuntu 12.04 Precise to 12.10 Quantal causes black screen

Disappointingly, I’ve just upgraded my 12.04 desktop to Ubuntu 12.10 Quantal release and the upgrade was not smooth. X failed to run. Given I use ATI’s proprietary driver, I assumed this was the issue. Unfortunately this didn’t seem to be the case as running the “Failsafe X” resulted in a black screen.

Recalling the pain when upgrading from 11.04 to 11.10 (https://uksysadmin.wordpress.com/2011/10/14/upgrade-to-ubuntu-11-10-problem-waiting-for-network-configuration-then-black-screen-solution/) and getting similar symptoms (although those issues related to networking) I ran through the same steps and I had X back again. The steps I did where:

  1. Boot into a safe session by selected Advanced Ubuntu Options from the Grub menu then choosing recovery mode
  2. Drop to a root shell
  3. rm -rf /var/run /var/lock
  4. ln -s /run /var
  5. ln -s /run/lock /var
  6. reboot

I then had X back and lightdm working. I then went to log in, but Unity didn’t seem to work (I still need to troubleshoot and will update here). My current work around was to install Gnome.

  1. Get to a console (try CTRL+ALT F1, although this mightn’t work – reboot into a root shell again)
  2. (If you don’t have networking, as the root user run the following: dhclient eth0)
  3. apt-get update
  4. apt-get install gnome
  5. reboot or restart lightdm (service lightdm restart)
  6. Under your username, choose the Ubuntu symbol above the > symbol to choose window managers and select Gnome
  7. Log in

To get Unity back:

  1. Fire up a console
  2. sudo apt-get remove –purge unity
  3. sudo apt-get install unity ubuntu-desktop

(thanks @EwanToo!)

I have no option to install proprietary hardware now – so I ‘ll see how my ATI FireGL card performs under the GPL driver…