A method involves synchronization of one or more secondary backup copies with a primary backup copy. The synchronization does not require additional reading of the original data, as the primary backup copy serves as a source of data. The synchronization process identifies difference between the primary backup copy and the secondary backup copy, so that only differential data is transferred and stored during the synchronization, eliminating the need to repeatedly transfer an entire copy to a secondary location. The method can leverage data compression and de-duplication for more efficient resource utilization.