This is the quick How''''''To to get x11vnc running on thin clients so you can connect to them using a vncviewer or the thin client manager app. note that this doc doesn't take security into account, if you want a safe solution enable a password for x11vnc

== Installing x11vnc ==

Before installing in the ltsp environment, make sure that apt-get sources in ltsp are consistent with the base install:
{{{ 
sudo cp /etc/apt/sources.list /opt/ltsp/i386/etc/apt/sources.list
}}}

Now, chroot into the ltsp client environment on the server.
{{{
sudo chroot /opt/ltsp/i386
}}}

Update the repositories that the ltsp environment uses for apt-get:

{{{
apt-get update
}}}

Install the x11vnc package (it's in the universe repository, possibly you must add it in /etc/apt/sources.list; in this case don't forget to apt-get update):

{{{
apt-get install x11vnc
}}}

== Setting x11vnc to run on the thin clients ==

'''Note:''': You might want to avoid this and skip to ''A safer and more secure way to run x11vnc on the thin clients'', below.

Now edit the rc.local file to add x11vnc to the system startup
(note: make sure this is all being done in the chroot environment and not the root of the server)

{{{
vi /etc/rc.local
}}}

You can use also nano for that, but first you have to install it on the chroot environment.

{{{
apt-get install nano
}}}

{{{
nano /etc/rc.local
}}}

Add the following line before the exit 0 statement in this file and save it:

{{{
x11vnc -display :6 -forever -loop -shared &
}}}

Now lets make sure rc.local gets actually executed: 

{{{
cd /etc/rc2.d
mv K99rc.local S99rc.local
}}}

== A safer and more secure way to run x11vnc on the thin clients ==

(if you've already done the section entitled ''Setting x11vnc to run on the thin clients'' then skip this one).

An alternative to editing rc.d is to run the following code snippet in the ltsp chroot to create an {{{/etc/init.d/x11vnc}}} init script:

{{{
# cat <<__END__ > /etc/init.d/x11vnc
case "$1" in
	start)
		start-stop-daemon --start --oknodo \
                        --pidfile /var/run/x11vnc.pid --background \
                        --nicelevel 15 --make-pidfile --exec \
			/usr/bin/x11vnc -- -display :6 -loop -passwdfile /etc/x11vncpassword -nossl
	;;
	stop)
		start-stop-daemon --stop --oknodo --pidfile /var/run/x11vnc.pid
	;;
	restart)
		$0 stop
		$0 start
	;;
	*)
		echo "Usage: $0 start|stop|restart"
	;;
esac
__END__
}}}

Then make it executable and link it into {{{/etc/rc2.d}}}:

{{{
# chmod 755 /etc/init.d/x11vnc
# cd /etc/rc2.d
# ln -s ../init.d/x11vnc S99x11vnc
}}}

Finally, create the {{{/etc/x11vncpassword}}} file with the password you want to use to connect to your thin clients:

{{{
# echo "thepassword" > /etc/x11vncpassword
# chmod 400 /etc/x11vncpassword
# chown root:root /etc/x11vncpassword
}}}

For better security you should consider setting x11vnc up to use system authentication (say, to your LDAP directory). That's far outside the scope of this HOWTO, but if you want to look into it you should start with the x11vnc documentation.

== Exit the chroot environment ==

Having installed the x11vnc package and set x11vnc up to run when the thin client starts up you are ready to exit the chroot environment:
{{{
exit
}}}


== Update the LTSP image ==

Ubuntu/Edubuntu 7.10 and onwards - Make sure that the ltsp image gets updated:

{{{
sudo ltsp-update-image
}}}

If you are using an i386 image on an AMD64 build the command is:
{{{
sudo ltsp-update-image --arch i386
}}}


== Testing it out ==

Reboot your thin clients and you should be able to connect to them via vnc now. For example, if you had a thin client at IP address 192.168.1.44 you could connect to it with:

{{{
xvnc4viewer -FullColour 192.168.1.44
}}}

(omit {{{-FullColour}}} for faster but uglier access to the remote screen).

You may find the {{{thin-client-manager}}} package and the strangely named {{{student-control-panel}}} command it installs useful when managing thin clients with VNC. Run the following command on the ltsp server (NOT in the ltsp chroot):

{{{
aptitude install thin-client-manager
}}}

then launch it with:

{{{
sudo student-control-panel
}}}

and browse your connected users, view their screens, etc.
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CategoryDocumentation