Ubuntu desktop in the cloud accessible with VNC

To create a Ubuntu desktop on Amazon EC2 that can be accessed by VNC I did the following steps:

1. Create 64-bit Ubuntu server instance
2. Install ubuntu desktop:

sudo apt-get install ubuntu-desktop

3. Install x11vnc

sudo apt-get install x11vnc

4. Install xvfb

sudo apt-get install xvfb

5. Configure x11vnc

sudo nano /etc/init/x11vnc.conf

 start on login-session-start  
 script  
 /usr/bin/x11vnc -xkb -auth /var/run/lightdm/root/:0 -noxrecord -noxfixes -noxdamage -rfbauth /etc/x11vnc.pass -forever -bg -rfbport 5900 -o /var/log/x11vnc.log  
 end script

And you should also set a password for your vnc sessions:

sudo x11vnc -storepasswd /etc/x11vnc.pass

6. Configure X server to use xvfb:

(Add the xserver-command line)

sudo nano /etc/lightdm/lightdm.conf

 [SeatDefaults]  
 greeter-session=unity-greeter  
 user-session=ubuntu  
 xserver-command=/etc/X11/xinit/xserverrc

(Replace the exec line)

sudo nano /etc/X11/xinit/xserverrc

 #!/bin/sh  
 #exec /usr/bin/X -nolisten tcp "$@"  
 exec Xvfb :0 -screen 0 1280x1024x24

7. Reboot and then log in using ssh port-forwarding:

ssh -L5901:127.0.0.1:5900 -i mypem.pem ubuntu@someserver.compute.amazonaws.com

8. Connect with VNC using a vnc viewer to your local machine (127.0.0.1) port 5901

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