A redundant disk array method includes allocating identically sized logical blocks of storage units together to form a stripe on each of several data storage devices, at least two of the logical blocks in the stripe being located on different data storage devices, generating a lookup table representing a mapping between a logical location of each logical block in the stripe and a physical location of the respective logical block on the corresponding data storage device, and writing data to the physical locations of each logical block in the stripe, the physical locations being obtained from the lookup table. In some cases, at least two of the data storage devices are heterogeneous, and at least two of the data storage devices have a different total number of logical blocks.