Patent ID: 8572340

Claim:
A method for performing an auxiliary copy operation, comprising: for each data block of a plurality of data blocks involved in a backup storage operation, with one or more processors comprising computer hardware, associating a signature value corresponding to the data block with one or more of a copy of the data block and a reference to a copy of the data block to form a signature/data word corresponding to the data block, wherein at least some of the signature/data words include the signature value corresponding to the data block and a reference to a copy of the data block that is stored in another signature/data word, but do not include a copy of the data block; logically organizing the signature/data words into a plurality of files, each file of the plurality of files comprising at least one signature/data word such that the signature values are embedded in the file; storing the plurality of files comprising the embedded signatures in at least one first storage device; with one or more processors comprising computer hardware, in response to an instruction to perform an auxiliary copy of at least one file of the plurality of files from the first storage device to at least one second storage device, and for each signature/data word in the at least one file: reading the embedded signature value corresponding to the signature/data word from the first storage device; transmitting the signature value; subsequent to said transmitting the signature value, receiving an indication as to whether a copy of the data block corresponding to the signature value exists at the second storage device; and reading a copy of the data block corresponding to the signature value from the first storage device if a copy of the data block does not exist at the second storage device, wherein a copy of the data block is not read from the first storage device if a copy of the data block does exist at the second storage device.