--- prelude: | Nova 13.0.0 release is including a lot of new features and bugfixes. It can be extremely hard to mention all the changes we introduced during that release but we beg you to read at least the upgrade section which describes the required modifications that you need to do for upgrading your cloud from 12.0.0 (Liberty) to 13.0.0 (Mitaka). That said, a few major changes are worth to notice here. This is not an exhaustive list of things to notice, rather just important things you need to know : - Latest API microversion supported for Mitaka is v2.25 - Nova now requires a second database (called 'API DB'). - A new nova-manage script allows you to perform all online DB migrations once you upgrade your cloud - EC2 API support is fully removed.