Abstract: There is provided a method of resynchronising a previous duplication, started at a first time, of a source logical drive on a destination logical drive. The method comprises tracking changes to the data on said source logical drive since said first time and starting a resynchronisation operation at a second time later than said first time. The resynchronisation operation comprises copying data from said source logical drive to said destination logical drive by copying only data which has changed since said first time. By providing such a method, the need to copy data which has not changed since the previous duplication operation is alleviated. This reduces the time and processing required to perform the resynchronisation operation by eliminating unnecessary transfer of data which has not changed since the earlier duplication.

Abstract: There is provided a method of resynchronising a previous duplication, started at a first time, of a source logical drive on a destination logical drive. The method comprises tracking changes to the data on said source logical drive since said first time and starting a resynchronisation operation at a second time later than said first time. The resynchronisation operation comprises copying data from said source logical drive to said destination logical drive by copying only data which has changed since said first time. By providing such a method, the need to copy data which has not changed since the previous duplication operation is alleviated. This reduces the time and processing required to perform the resynchronisation operation by eliminating unnecessary transfer of data which has not changed since the earlier duplication.

Abstract: There is provided a method of, and apparatus for, duplicating a logical drive. The method includes sequentially copying data from a source logical drive to a destination logical drive, and determining whether a write request to the source logical drive is received during the sequential copying. If so, the step of copying data in the write-requested data area to an additional storage area is carried out prior to executing the write request. It is further specified that the data in the write-requested data area is to be ignored and not copied during the sequential copying. The method further includes copying, upon completion of the sequential copying, data from the additional storage area to the destination logical drive.