Get CEPH backup
It is great when you have a backup or you don't destroy your network under an erasure-coded pool.
rbd export -p pool volume-ad0ceef0-64ef-4050-afd6-3a12c13dd6be ./volume-ad0ceef0-64ef-4050-afd6-3a12c13dd6be.bac
Restore CEPH from backup
rbd rm pool volume-ad0ceef0-64ef-4050-afd6-3a12c13dd6be
rbd import ./volume-ad0ceef0-64ef-4050-afd6-3a12c13dd6be.bac pool/volume-ad0ceef0-64ef-4050-afd6-3a12c13dd6be
Manipulate CEPH block storage (VM disk)
From time to time, you need to do some artwork inside VM. To do so, you first need to be able to mount RBD.
rbd export <pool>/<volume> /tmp/<uuid> #backup if needed
dev=$(rbd map <pool>/<volume> )
sgdisk --print ${dev} #record current layout
rbd showmapped
rbd unmap ${dev}