Open Stack

Phillip Pao wrote:

> "it would be nice for cinder to have a concept of a read-only volume that could be attached to multiple instances"

Or to be more precise, to be able to create thin volumes that overlayed a read-only base, where multiple instances
could each reference their own overlay of the common read-only base.

Further, we should allow that reference image to be replicated, so as to allow the cloning to be done as close to the
working VM as possible.