---
features:
  - When RBD is used for ephemeral disks and image storage, make
    snapshot use Ceph directly, and update Glance with the new location.
    In case of failure, it will gracefully fallback to the "generic"
    snapshot method.  This requires changing the typical permissions
    for the Nova Ceph user (if using authx) to allow writing to
    the pool where vm images are stored, and it also requires
    configuring Glance to provide a v2 endpoint with direct_url
    support enabled (there are security implications to doing this).
    See http://docs.ceph.com/docs/master/rbd/rbd-openstack/ for more
    information on configuring OpenStack with RBD.