Temperamental VNC

[Michael Pavling]

I've been getting an annoying problem on a new machine I've set up.
It's running Ubuntu 10.04.1 AMD64 desktop, but is "headless". If I ssh
onto it and launch VNCserver (I've installed TightVNC) I can log on
and it works fine for a time. But at some point - generally when I
click a button in VirtualBox, the VNC viewer closes on my PC, and in
my ssh window, I can see that the VNC server process has died.
Starting a new vncserver starts on a new port (as there are still
locks in /tmp from the previous process).

Any idea what's causing VNC to die? Or is there a better/different way
to administer a headless machine (I'm temporarily using remote desktop
to avoid the process terminations, but I have to be logged in on the
console for it to work, which isn't acceptable long term - I need to
be able to reboot without concern)

Cheers,