Patent ID: 8412905

Claim:
A method of backing up a data store comprising: in a storage system having a controller, the data store operative to interface with a host device and the host device operative to communicate with a primary removable data store, the controller: receiving a notification originating from the host device of deletion of first data from a primary removable data store, the primary removable data store configured to be coupled to and uncoupled from the host device as a removable storage device; wherein when the primary removable data store is coupled with the host: determining whether sufficient free space exists in a deleted data store to store therein the first data, wherein the deleted data store is configured to store data deleted from the primary removable data store, and wherein the deleted data store is separate and apart from the primary removable data store so as to maximize storage space for non-deleted data in the primary removable data store; if sufficient free space exists in the deleted data store to store therein the first data, storing the first data in the deleted data store so as to provide recoverable deleted data storage for the primary removable data store; if sufficient free space does not exist in the deleted data store to store therein the first data, (a) removing data from the deleted data store in accordance with a criterion, thereby increasing an amount of free space in the deleted data store, in order to accommodate the first data in the deleted data store, and (b) storing the first data in the deleted data store; and determining whether sufficient free space exists in a secondary data store to store therein the first data, the secondary data store configured to mirror data in the primary removable data store.