Can someone tell me whether setting positive and negative VM affinity rules will be at all possible with oVirt at some point in time, i.e. is this on the roadmap?
I need to be able to tell VM's to run on different hosts, spread them around, so to speak. For example, domain controllers would be better off running on as many different hypervisors as possible, the way I see it. That way, the failure of a single hypervisor has minimal impact on the infrastructure. I know there is a feature to pin VM's to a single hypervisor, but that's not quite the same. I would like to group the domain controllers and then tell them not to run on the same host as other members of that group as much as possible.
The other way around would be nice as well: have several VM's run on the same hardware. For example, a three tiered web application would probably perform better if the VM's are all on the same hypervisor. I know I could pin them all to the same hypervisor, but still: that's not quite the same. I want to be able to group the web app VM's and tell them to try to run on the same hypervisors as the other members of the group, so they can move to another hypervisor as a group if the need arises.
Apologies if this has been asked before or documented in some place I haven't looked yet.