--- features: - Nova now defaults to using the glance version 2 protocol for all backend operations for all virt drivers. A ``use_glance_v1`` config option exists to revert to glance version 1 protocol if issues are seen, however that will be removed early in Ocata, and only glance version 2 protocol will be used going forward. upgrade: - It is now required that the glance environment used by Nova exposes the version 2 REST API. This API has been available for many years, but previously Nova only used the version 1 API.