[Engine-devel] oVirt upstream meeting : VM Version

[Eli Mesika]

Hi

We had discussed today the Stable Device Addresses feature
One of the questions arose from the meeting (and actually defined as an open issue in the feature wiki) is:
What happens to a 3.1 VM running on 3.1 Cluster when it is moved to a 3.0 cluster.
We encountered that VM may lose some configuration data but also may be corrupted.
>From that point we got to the conclusion that we have somehow to maintain a VM Version that will allow us to 
block moving VM if it's version is not fully supported compatible with the target Cluster.
One idea for getting the VM version is the OVF which actually holds inside its header OvfVersion.
The question is , is the OVF good enough for all our needs or should we persist that else (for example in DB)
Also, any other issues/difficulties we may encounter implementing and storing VM version.

Keep in mind that this is a new feature that impacts the Stable Device Addresses feature but may be useful/relevant
for other features as well.

Thanks

Eli