I have 2 Ubuntu 14.04 boxes configured with SSH, X11VNC. I have previously successfully achieved a remote desktop session using Remmina. Now whenever I connect, I only see a window with the client area all black.
The host server shows that I am successfully connected (per /var/log/auth.log). I've tried different resolutions and get the same result.
A few days ago I performed the recommended SW updates on the host server box. Perhaps this changed some configuration file.
I discovered that the reason I was getting the black window was because there were 2 simultaneous users logged-into the host server.
It would not work (black display on client) if:
- 2 users were logged-in regardless of which user had the primary display, or
- only 1 user was logged-in but was screen-locked and had not been re-assigned the primary display (had not unlocked the display since the 2nd user had used the display).
Conversely, the remote display would work if:
- only 1 user was logged-in AND that user either [did not have screen lock engaged OR [had locked the screen AND no other user had logged-in since the user had engaged screen lock]].
I wonder if this is explained in a man page somewhere.