On 10/01, Dan Smith wrote:
Good to know that it is not necessary for nova to go through ALL intermediate releases and perform db-sync The question is if this is true for ALL openstack services (in our deployment the controller node is used for all services and not only for nova)
Actually, Sean is wrong here - we do expect you to go through each release on the controller, it's just that it's rare that it's actually a problem. We have had blocker migrations at times in the past where we have had to ensure that data is migrated before changing or dropping items of schema. We also recently did a schema compaction, which wouldn't tolerate moving across the releases without the (correct) intermediate step.
We definitely should fix the problem related to compute records being old and causing the controllers to start. However, at the moment, you should still assume that each intermediate release needs to be db-sync'd unless you've tested that a particular source and target release works. I expect the same requirement for most other projects.
--Dan
Hi, Unrelated to this Nova issue, but related to why intermediate releases cannot be skipped in OpenStack, the Cinder project requires that the db sync and the online data migrations are run on each intermediate release. You may be lucky and everything may run fine, but it might as well blow up in your face and lose database data. Cheers, Gorka.