[kwlug-disc] GUI Remote Access

[B.S.]

On 06/23/2017 06:35 PM, Khalid Baheyeldin wrote:
> Say you have two desktops, both running Ubuntu 16.04 with XFCE.
> 
> What are the available packages to allow on to access the other from and to
> the full GUI?
> 
> VNC was a solution some time ago. Also there was NoMachine.
> 
> What packages do I need at either end?

Assumptions:
- you will be connecting via ssh first. i.e. You aren't expecting to
native app connect across the internet via non-ssh ports, directly.
[Could easily be a net only shell-less ssh connect, too.]
- you aren't looking to create your own session that survives logoff.
e.g. screen, or 2nd X session, etc.
- you are looking to go from one desktop to another. DISPLAY=:0 on both
sides.


In /etc/kde4/kdm/Xsetup, or your appropriate place (often within /etc/xdg?):

HOME=/root /usr/bin/x11vnc -nossl -display :0 -rfbport 5900 -noipv6
-shared -forever -tightfilexfer -rfbauth /etc/passwd-vnc-full -users
+nobody -solid black -logfile /var/log/x11vnc -flag /var/log/x11vnc-port
-rmflag create:/var/log/x11vnc-pid -skip_lockkeys -clear_mods
-clear_keys -clear_all -gui simple,tray -unsafe -permitfiletransfer
-alwaysshared -ncache 10 -ncache_cr -allow <A.B.C. of your net, e.g.
'192.168.0.'> -bg > /var/log/x11vnc.log 2>&1


I have an alias 'vnc' that auto-connects to the above. Executables
fetched from http://www.tightvnc.com/download.php, I believe - TightVNC
Java Viewer.

Looks like I run 1.6.0_41 (as later versions prompt / work directly over
ssh, and I'm explicitly looking to not be prompted - if I need ssh, I
will have started it already).

The script that the vnc alias calls includes:

eval "java -jar /usr/local/src/tightvnc-jviewer.jar $@ $server $passargs
-AllowClipboardTransfer -ShareDesktop -CompressionLevel=1
-JpegImageQuality=Lossless  -LocalPointer=On -ColorDepth=8
-ScalingFactor=88 &> /dev/null &"

This all 'just works'.


In some cases I've had remotes that autossh in to me (net only), others
openvpn in. In the ssh cases I can set up auto-remote/local port
forwards, in the vpn cases they have an ip so forwards aren't needed.


More caveats:
- The above describes vnc starting up with X, so you can see the initial
login. And survive an X logout.
- I auto-login to X with auto-screenlock set. i.e. X is started and all
user initial X things completed by the time I get there. I still need to
unlock the screen, but at least all the initial stuff has run.

If you don't start X with the system, that's OK - whenever you do ssh in
and start X, vnc will come along for the ride, above.

If vnc fails along the way (usually because I've killed it for some
reason), I have an alias to start it (while ssh'ed in):

alias startvnc='x11vnc -nossl -display :0 -shared -forever
-tightfilexfer -avahi -allow A.B.C. -unsafe -q -N -rfbport 5900 -usepw
-noipv6 -bg -gui tray'


HTH. GL&HF.