Hi, We have an issue regarding live migrate old instances. On our infrastructure based on Newton, we had not well named our aggregation groups and we decided to completely change the naming conventions. We are using extra specs/metadata in flavors/aggregates and AggregateInstanceExtraSpecsFilter to select the set of hosts. After changing one of the key (lets call it 'kind') of extra spec/metadata to the new value, we are able to create new instances, but unable to live-migrate old one. This is because of stored flavor extra specs in instance_extra, which still holds the old value for the 'kind' key, and make the aggregate filter fail to match the hosts. In our opinion, it should be able to live-migrate such instance, since only the flavor metadata has changed, while other fields doesn't (vcpus, memory, disk). Is it a bug? Or maybe it is possible to change the instance flavor extra spec? -- Cheers, Roman Dobosz