[libvirt] about ceph+qcow2+qemu(snapshot) support issue ?

Hi , Could you pls help me ask one question , now we are testing a fuction , about Ceph+ qcow2+(qemu(snapshot) tec, now we are running this command print this error : virsh snapshot-create-as --domain win08q2 --name snapwin08q2 --description "test ucsm+qcow2"error: operation failed: Error -5 while writing VM so we want to confirm that the ceph rbd if support qemu qcow2 format oneline snapshot , thanks a lot!