Black screen on Tensorflow

After having problems on connecing to GPUs in Julia, I decided to give a trial in updating Ubuntu and Lambda stack, folloiwng the instructions given here:

Unfortunately, after the command
sudo do-release-upgrade,
The computer restarted and a black screen with a small white “-” on the left top of the screen appear, and apparently it does not respond to any command.

I would like to ask advices on how to solve this problem.

This likely means that the GUI terminal session is in use.

  1. Hit one of the combinations ‘Control-Alt-F2’ to ‘Control-Alt-F5’
    • This will go to a command line session
  2. Login
  3. Clean up and reconfirm install
    • One reason is some commands create a xorg.conf
      $ sudo rm /etc/X11/xorg.conf
    • Check if apt is up to date or if there is a issue.
      $ sudo apt update
      $ sudo apt upgrade
      If you get errors like ‘–fix-missing’ and/or ‘–configure’
      $ sudo apt install --fix-missing
      or
      $ sudo dpkg --configure

And you may need to clean up:

 /etc/apt/sources.list
 /etc/apt/sources.list.d/*