Hi @UAnton ,
In short, AFAIK on CEPH you can’t delete a snapshot if it has leafs.
According to RBD Layering — Ceph Documentation
“Before cloning a snapshot, you must mark it as protected, to prevent
it from being deleted while child images refer to it:”
…
“To delete the parent, you must first mark it unprotected, which checks
that there are no children left:”
There is a feature request in the backlog to made the snapshot delete limitations that are implemented in OpenNebula as optional because there are storages that do not suffer from such limitations ;).
IMO the current implementation is suitable in the cases when you want to test something and if succeeded - revert and do it permanently. I am using it this way to test the automated installation of our addon.
Kind Regards,
Anton Todorov