Comment 3 for bug 1077817

You can use different pools within a single ceph cluster to do that. Pools may share any number of osds, from 0, some, to all, depending on your crush rules (see http://ceph.com/docs/master/cluster-ops/crush-map/). So you could have one pool with ssds, and another with sata disks. Currently this would require two instances of nova-volume or cinder-volume, one for each pool.