Patent ID: 7360048

Claim:
A method comprising: writing a data object to a source data image at one of a plurality of controlled storage apparatus; copying by a first copy component said data object to a first target data image at one of said plurality of controlled storage apparatus responsive to a first metadata state; responsive to a second metadata state performing, by a second copy component, a step selected from a group consisting of: controlling copying of said data object to a second target data image at one of said plurality of controlled storage apparatus; and causing said first copy component to perform copying of said second target data image to said first target data image; and cascaded copying of said data object to a third target data image at one of said plurality of controlled storage apparatus by a third copy component; wherein one of said second and said third copy components is operable to control cascaded copying of a delimited subsequence of data images responsive to a third metadata state indicating currency of a grain of data in one of said second and said third target data images.