A first entity for backing up a data volume of a primary storage system in a secondary storage system , configured to: determine one or more operations performed on the data volume of the primary storage system , wherein the one or more operations are reversible; generate one or more sets of instructions , wherein each set of instructions is associated with a respective operation of the one or more operations , and each set of instructions is indicative of how to perform the respective operation and how to perform an inverse operation of the respective operation ; and provide the one or more sets of instructions to a second entity on the secondary storage system , wherein the first entity is further configured to: obtain a first snapshot of the data volume of the primary storage system at a time point T1; and provide the first snapshot to the second entity for creating a first backup image of the data volume at time point T1; determine a first operation performed on one or more files of the data volume after the time point T1 and before a time point T2, wherein files of the data volume other than the one or more files remain unchanged; and provide a first set of instructions associated with the first operation to the second entity for creating a second backup image of the data volume at time point T2, wherein the first set of instructions is indicative of how to perform the first operation on the one or more files to create updated one or more files, and how to perform an inverse operation of the first operation on the updated one or more files to obtain the one or more files. determine one or more operations performed on the data volume of the primary storage system , wherein the one or more operations are reversible; generate one or more sets of instructions , wherein each set of instructions is associated with a respective operation of the one or more operations , and each set of instructions is indicative of how to perform the respective operation and how to perform an inverse operation of the respective operation ; and provide the one or more sets of instructions to a second entity on the secondary storage system , wherein the first entity is further configured to: obtain a first snapshot of the data volume of the primary storage system at a time point T1; and provide the first snapshot to the second entity for creating a first backup image of the data volume at time point T1; determine a first operation performed on one or more files of the data volume after the time point T1 and before a time point T2, wherein files of the data volume other than the one or more files remain unchanged; and provide a first set of instructions associated with the first operation to the second entity for creating a second backup image of the data volume at time point T2, wherein the first set of instructions is indicative of how to perform the first operation on the one or more files to create updated one or more files, and how to perform an inverse operation of the first operation on the updated one or more files to obtain the one or more files. obtain a first snapshot of the data volume of the primary storage system at a time point T1; and provide the first snapshot to the second entity for creating a first backup image of the data volume at time point T1; determine a first operation performed on one or more files of the data volume after the time point T1 and before a time point T2, wherein files of the data volume other than the one or more files remain unchanged; and provide a first set of instructions associated with the first operation to the second entity for creating a second backup image of the data volume at time point T2, wherein the first set of instructions is indicative of how to perform the first operation on the one or more files to create updated one or more files, and how to perform an inverse operation of the first operation on the updated one or more files to obtain the one or more files. <EOS>