--- upgrade: - | The libvirt driver's RBD imagebackend no longer supports setting force_raw_images to False. Setting force_raw_images = False and images_type = rbd in nova.conf will cause the nova compute service to refuse to start. To fix this, set force_raw_images = True. This change was required to fix the `bug 1816686`_. Note that non-raw cache image files will be removed if you set force_raw_images = True and images_type = rbd now. .. _bug 1816686: https://bugs.launchpad.net/nova/+bug/1816686