Hi, In a Yoga cloud, I upgraded all the core services and 1 compute to Antelope (directly from Yoga, using a SLURP upgrade). This cloud has 4 compute servers, all using the same HW (Dell FX2/FC630 with Broadwell CPUs). After the upgrade, any attempt to live migrate a VM from a Yoga compute to the Antelope compute fails with the following error in destination/Antelope nova-compute.log: nova.exception.MigrationPreCheckError: Migration pre-check error: Unacceptable CPU info: CPU doesn't have compatibility. This looks weird. I don't see anything in the release notes related to this problem, except a mention that the API used to do the comparison has changed ("This change replaces the usage of older API, compareCPU(), with the new one, compareHypervisorCPU()."). "virsh capabilities" reports the same thing for a Yoga and an Antelope compute, except the addition of a feature 'flush-l1d' in Antelope and the addition of 2 new attributes in the '<cpu>' section: <signature family='6' model='79' stepping='1'/> <maxphysaddr mode='emulate' bits='46'/> I tend to think that additions are not a problem in general and so it doesn't seem to explain the problem I'm facing. Anybody with a similar experience? It seems to me a different problem that the one that has been faced in the past (before Nova 20 if I'm right) and described in several posts, with CPU model improperly detected (in particular Broadwell vs. Icelake). Thanks in advance for any hint/suggestion. Best regards, Michel