Systems and methods for retaining and using data block signatures in data protection operations

Abstract

A system according to certain embodiments associates a signature value corresponding to a data block with one or more data blocks and a reference to the data block to form a signature/data word corresponding to the data block. The system further logically organizes the signature/data words into a plurality of files each comprising at least one signature/data word such that the signature values are embedded in the respective file. The system according to certain embodiments reads a previously stored signature value corresponding to a respective data block for sending from a backup storage system having at least one memory device to a secondary storage system. Based on an indication as to whether the data block is already stored on the secondary storage system, the system reads the data block from the at least one memory device for sending to the secondary storage system if the data block does not exist on the secondary storage system, wherein the signature value and not the data block is read from the at least one memory device if the data block exists on the secondary storage system.

What is claimed is: 
     
         1 . A method of performing an auxiliary copy operation from a backup storage system to a secondary storage system, the method comprising:
 in response to instructions to copy at least some of a plurality of backed up data blocks from a backup storage system comprising at least one memory device to a secondary storage system, for each of the at least some data blocks:
 reading, with one or more processors, a previously stored signature value corresponding to the respective data block for sending from the backup storage system to the secondary storage system; and 
 based on an indication as to whether the data block is already stored on the secondary storage system, reading the data block from the at least one memory device for sending to the secondary storage system if the data block does not exist on the secondary storage system, wherein the signature value and not the data block is read from the at least one memory device if the data block exists on the secondary storage system.