To connect to my Ubuntu machines and get the Gnome desktop remotely, I did the following:
- Installed nomachine client, node and server on the server
- Installed nomachine client on the client
- Updated the firewall rules on the server to allow ssh access from the client
I found these instructions useful.
Note: After I installed a newer version of OpenSSH on the server, the keys changed. I encountered an authentication error that refered to keys in /usr/NX/home/nx/.ssh/known_hosts. I could log on after I removed the file on the server (after backing it up).