I've been manage several servers with different operating systems for a couple of years. I used VNC to remotely view and manage Linux/ UNIX servers through their X displays. If you ever used and configure VNC server at Windows OS, you might find a slight differences with the one at Linux/ UNIX. In windows, you can configure VNC and use it with any display, yet you still can view your real desktop display, the one that you've been and always used. But in Linux/ UNIX, when you configure your VNC server, you can't configure it to connect to your real X display, indeed it always create a new display, so you can't view your existing open applications.

Recently I just found out a very simpe and right Linux/ UNIX application for that purpose, it called x11vnc. X11vnc is a VNC server for real X display, it allows one to view remotely and interact with real X display. With this tools, now I can view and control any X applications running on my server. The usage is very simple either.

First, you must install this tools. For I am using Ubuntu server, this is the command:

server# apt-get install x11vnc

And after it installed, execute this command to run VNC server:

server# x11vnc -display :0

You'll get some notifications upon execute the command, its for security purposes (access password, etc.), just read and customize it according to your server configuration.

After done with above command, you can view X server's display from your client using this command:

client# vncviewer server:0

That's it. If you run the command on server with no errors, right now you can view your real X server's display, with any X application already running on it. Cheers! :)