Configuration to point an X tty to a separate system?

Question

Specifically, I have an Ubuntu 10.04 system with a headless Ubuntu 12.04 virtual machine, and I'm looking for a way to have it set up so pressing Ctrl+alt+F8 will take me into another X client which is connected to an X server on the VM (with gdm appropriately displayed at startup, etc.). As in, my startup script should spin up the headless machine and then immediately perform a startx pointed at the vm.

Answer 1

If you enable XDMCP in the guest's DM then you can use X :1 -query ... in the startup scripts on the host to request a XDMCP connection to the X server running in the guest. This will open :1 onto your guest, starting from the login screen. See the Xserver(1) man page for details.