Headless X Session with x11vnc
Overview
It’s possible to securely run graphical workloads on headless remote Linux servers using x11vnc, ssh, and xvfb.
Configuration
Install Software
In this example, the software is installed on a stock Ubuntu server.
- x11vnc: The server creating the X11 session
- xvfb: The virtual frame buffer for headless systems
- fluxbox: Lightweight window manager
sudo apt install x11vnc xvfb fluxbox
Setup VNC Server
VNC does not encrypt traffic by default. To securely connect, we wrap the VNC session in a port forwarded ssh tunnel. To simplify the process, the following one-line command will setup a ssh tunnel, start the x11vnc server with xvfb, and setup the fluxbox windows manager:
ssh -L 5900:localhost:5900 192.168.86.5 "x11vnc -create -env FD_PROG=/usr/bin/fluxbox -env X11VNC_CREATE_GEOM=${1:-1024x768x16} -nopw -listen 127.0.0.1 -forever"
Connect
Connect to the Remote Host
Connect to the remote host with a vnc client. Since the session is wrapped in a port-forwarded ssh tunnel, the connection is made to localhost:5900 NOT the IP address of the remote system.
A full fluxbox X session is tunneled over ssh using vnc:
