[Engine-devel] RFE: SPICE and VNC graphics at the same time

[Frantisek Kobzik]

Dear devels,

I started working on a feature that allows user to run a VM with both SPICE and VNC graphics [1]. In the engine we derive the graphics server type (SPICE/VNC) from the video device (QXL/CIRRUS), which I think is wrong. These are two different things and should be treated separately. What I suggest is to split that configuration in vm_static into two fields:
 1, (already existing) Display type with values QXL or CIRRUS
 2, (new) Graphics types - enum or comma-separated string that indicates that the VM should be run with 'spice'/'vnc'/'spice,vnc'/'auto' (the last means that the type will be derived from the video device which is current behavior.

The feature would consist of three patches:
 - vdsm - add new field in vm.conf with information about graphics types of a vm.
 - engine backend - add graphics types to VM and corresponding entities, adjust xml rpc communication.
 - engine frontend - "only" adjust the ui.

The patches would be backwards compatible with older engine/vdsm versions.

There are some things that must be taken into account, mostly it's about differences in SPICE/VNC supported features (like multimonitors, single qxl, smartcard, migration...). e.g. if you run a vm with both graphic types together the engine should probably disallow some spice features. But this is more of an implementation detail.

Feel free to reply if you have anything to say about this feature.

Cheers,
Franta.


[1]: https://bugzilla.redhat.com/show_bug.cgi?id=976044