When using the (default) option VM_MAD:KEEP_SNAPSHOTS is off,
OpenNebula does not make a proper cleanup of the “pyhsical” qemu-img snapshot stuff - if not doing so - old qemu-img snapshot keeping old space,
which then is unvisible from OpenNebula.
(after some kind of migrations, live-migrations … the OpenNebula shapshots are gone, means not visible anymore in the gui)
The unexperienced OpenNebula admin would never be aware of that situation, that the image does occupy “unused” space.
Thx a lot for any input. i do appreciate.