How to setup x11vnc to access with graphical login screen?

Solution 1:

The above answers solve the problem, though a couple of amendments for versions of Ubuntu with systemd (15.04+), as follows:

• Take advantage of new -auth guess functionality in x11vnc - which helps!
• Update for systemd (not upstart)

Run the following to install:

sudo apt-get install x11vnc
sudo x11vnc -storepasswd yourVNCpasswordHERE /etc/x11vnc.pass
# for Ubuntu 15.04+
sudo nano /lib/systemd/system/x11vnc.service
# for Ubuntu 16.10+
sudo nano /etc/systemd/system/x11vnc.service

Insert this into the file:

[Unit]
Description="x11vnc"
Requires=display-manager.service
After=display-manager.service

[Service]
ExecStart=/usr/bin/x11vnc -xkb -noxrecord -noxfixes -noxdamage -display :0 -auth guess -rfbauth /etc/x11vnc.pass
ExecStop=/usr/bin/killall x11vnc
Restart=on-failure
Restart-sec=2

[Install]
WantedBy=multi-user.target

Then, start with:

sudo systemctl daemon-reload
sudo systemctl start x11vnc

And ensure the service starts on boot:

sudo systemctl enable x11vnc

Solution 2:

Install x11vnc:

sudo apt-get install x11vnc

Create a password for your user:

x11vnc -storepasswd

If you have ssh setup you can use it to start x11vnc assuming you are logged in already, but remember to tell it to use your password file:

x11vnc -usepw

If you are not logged in you will get an error with the explanation:

If NO ONE is logged into an X session yet, but there is a greeter login
program like "gdm", "kdm", "xdm", or "dtlogin" running, you will need
to find and use the raw display manager MIT-MAGIC-COOKIE file.
Some examples for various display managers:

 gdm:     -auth /var/gdm/:0.Xauth
          -auth /var/lib/gdm/:0.Xauth
 kdm:     -auth /var/lib/kdm/A:0-crWk72
          -auth /var/run/xauth/A:0-crWk72
 xdm:     -auth /var/lib/xdm/authdir/authfiles/A:0-XQvaJk
 dtlogin: -auth /var/dt/A:0-UgaaXa

Assuming you are using lightdm for the login you can fix this problem you can start x11vnc with the command:

sudo x11vnc -xkb -noxrecord -noxfixes -noxdamage -display :0 -auth /var/run/lightdm/root/:0 -usepw

I am not sure this is the best idea to run x11vnc as root. Maybe someone could edit with a way to access the login without using sudo.

Once this is running you should be able to connect using a vnc client such as krdc (for KDE). You might want to use GNU Screen to keep x11vnc running without needing the ssh session open

I was able to figure this out using http://ubuntuforums.org/showthread.php?t=2039022.

Here is a sample upstart job you can use to make it run at startup. It needs to be put in /etc/init/x11vnc.conf. (Note that newer versions of Ubuntu use systemd so see the other answer that has a sample systemd config):

# description "start and stop x11vnc"

description "x11vnc"

start on runlevel [2345]
stop on runlevel [^2345]

console log
#chdir /home/
#setuid 1000
#setgid 1000

respawn
respawn limit 20 5

exec x11vnc -xkb -noxrecord -noxfixes -noxdamage -display :0 -auth /var/run/lightdm/root/:0 -usepw

Once you have made this file you can start it by running: sudo start x11vnc You can check the log at: /var/log/upstart/x11vnc.log

Solution 3:

Here's how:

1. Install the X11VNC server (or through Ubuntu Software Center -> X11VNC Server)

   sudo apt-get install x11vnc
   

2. Create a VNC password file.

   sudo x11vnc -storepasswd yourVNCpasswordHERE /etc/x11vnc.pass
   

3. Create a job file in the editor nano (or gedit, leafpad etc.).

   sudo nano /etc/init/x11vnc.conf
   

4. Paste this into the file:

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

5. Save the file. You created a job for the Upstart event login-session-start.

6. Restart Ubuntu.

That's it! You should now be able to connect with any VNC client even before login.