RBD Layering — Ceph DocumentationRBD Layering¶ RBD layering refers to the creation of copy-on-write clones of block devices. This allows for fast image creation, for example to clone a golden master image of a virtual machine into a new instance. To simplify the semantics, you can only create a clone of a snapshot - snapshots are always read-only, so the rest of the image is unaffected, and there’s no possibility of writing to th
