When the media ask whether cloud computing is ready for prime time, the key topics are resilience and security. Back-up and restore capabilities play an important role for resilience. The ability to recover from adverse events, whether natural disasters, sabotage, disk failures, or other, needs to be broader and more granular than it typically is for on-premises customers. The reasons for this include the concentration of a high number of users being served from one data center and the multi-tenant nature of the system. This means we need the ability to restore not just the whole data center, but also individual companies, individual servers, or individual users, depending on what parts of the system were affected by the disaster. If a limited disaster has rendered an individual company or user 'corrupted', we don't want to have to do a system level restore affecting all users and/or all companies in order to recover those who were corrupted. Rather, we want to be able to perform a restore operation for only the affected companies, servers, or users. Per tenant back-up and restore capability is similarly an important idea unique to multi-tenant cloud environments, though not generally implemented and automated.