I guess u r trying to use VNC over ssh
. Its the more secure way than using normal unencrypted VNC connection.
I can login to the command line just fine and get root up and running but when I start the VNCviewer I get a Failed to connect to server.
I suppose u tried to run vnc viewer on your computer not remotely via ssh. If that is the case and u couldnt connect to the server u should check firewall settings.