Description of problem: Running a fully-virt HVM domain with VNC results by default in a VNC port being opened on port 5900+$DOMAINID. This is unscalable past the first 100 domains created on a host, beyond which point the port will clash with the primary X server port. This default is good for developers who constantly reboot but not suitable for production. Version-Release number of selected component (if applicable): xen-3.0.2-23 How reproducible: 100% Additional info: The domain ID is available from xenstore and there is a xen option in current upstream, "vncunused=1", to let it choose the first free port. This probably wants to be enabled by default.
We need to ensure whatever we do here is consistent for paravirt guests as well
There's support for vncunused for both PV and FV guests that can be set both in the xen config and with libvirt (and xenguest-install)