Patent ID: 8521707

Claim:
An article of manufacture comprising a computer readable storage device including code executed to communicate with a memory and storage locations and to perform: maintaining an image of data in a memory, wherein the image in the memory includes a generation number for the image; writing the image in the memory to at least two copies of the image to storage locations in response to a first event, wherein the generation number for the image in the memory is stored in the storage locations having the copies; setting check generation numbers for the copies of the image to the generation number of the image in the memory; loading the image from at least one of the copies of the image in one of the storage locations to the memory in response to a second event; incrementing the generation number for the image loaded into the memory from the at least one of the copies of the image; incrementing the check generation numbers for the copies of the image in response to the second event; and using the generation numbers for the copies of the image in the storage locations and the check generation numbers of the copies of the image to validate the copies of the image.