Where to define user's desktop environment for VNC connections

[ccReynolds]

I'm having trouble figuring out where the desktop environment a user wants is defined. I have a headless workstation setup at home that is running x11vnc for the server and I connect to with TightVNC. I can log in with different users and get a unique desktop for each. However, I can't figure out where to define what environment the VNC connection uses. It always defaults to Unity. I have gnome-fallback installed and I would like to use that.

My original install was 12.04 LTS Desktop. I have made the following changes:
/etc/default/grub

GRUB_CMDLINE_LINUX_DEFAULT="text"

I have set the following in ~/.dmrc:

[Desktop]
Session=gnome-fallback
I have set the following in /etc/lightdm/lightdm.conf:

[SeatDefaults]
greeter-session=unity-greeter
user-session=gnome-fallback
~/.xsession

gnome-session --session=gnome-fallback

[slickymaster]

How to change to other desktop environment on VNC sessions (http://askubuntu.com/questions/352232/how-to-change-to-other-desktop-environment-on-vnc-sessions)

[ccReynolds]

I tried the instructions and it did not help.

I created a ~/.vnc/xstartup file as executable & added the following:


#!/bin/sh

#Uncommment this line if using Gnome and your keyboard mappings are incorrect.
#export XKL_XMODMAP_DISABLE=1

# Load X resources (if any)
if [ -r "$HOME/.Xresources" ]
then
xrdb "$HOME/.Xresources"
fi

gnome-session --session=gnome-fallback &

[steeldriver]

AFAIK the ~/.vnc/xstartup file is only used by independent VNC servers (vnc4server / tightvncserver) - x11vnc is intended as a 'desktop sharing' VNC server i.e. it doesn't start a session of its own, it just relays whatever desktop the user's 'real' X server is running on. That will be set when the user logs in via lightdm (and defaults to the user's previous session - saved via /var/lib/AccountsService/users/ I think rather than ~/.dmrc).

[ccReynolds]

Thanks for the info. That was a detail I had not picked up on. The VNC connection is not using what is set in /var/lib/AccountsService/users. That file has a different desktop and wallpaper in its config file.

I am using xvfb with x11vnc. Could that be forcing it to look somewhere else?

[ccReynolds]

I'm still baffled by where the system is looking to come up with the unity desktop. It was still trying to pull up Unity after I completely uninstalled unity-desktop. I was finally able to get the result I wanted by performing the following:

Original startup line from putty:

x11vnc -nofbpm -noxdamage -create -usepw -geometry 1280x1024 -auth ~/.Xauthority &

Started x11vnc with the previous command plus the following to clean out the previous session:

-gone 'killall Xvfb'

Closed the vnc connection. Then removed the -gone 'killall Xvfb' bit and added the following:

-env FD_PROG=/usr/bin/gnome-session-fallback

Even after this is done, if I try to restart using the original string unity tries to come up.

Got the idea for the mods to the x11vnc command here:
http://www.richud.com/wiki/Ubuntu_Fluxbox_GUI_with_x11vnc_and_Xvfb

[steeldriver]

What's the advantage of using x11vnc+Xvfb? if you install a standalone VNC server (like tightvncserver or vnc4server) you would be able to specify whatever session you want via ~/.vnc/xstartup

[ccReynolds]

I liked the fact that you had more than just one option for frame buffers e.g. Xdummy, and I liked the that it had the option to automatically close after you end your session. However, it was probably based more on the fact that I found better examples for it than any sound technical reason.


What's the advantage of using x11vnc+Xvfb? if you install a standalone VNC server (like tightvncserver or vnc4server) you would be able to specify whatever session you want via ~/.vnc/xstartup