Method and apparatus for performing logical duplication of backup data in
a computer system including a host computer, a storage device storing data for
the host computer, and at least one computer-readable backup storage medium storing
backup data copied from the storage device, is disclosed. In one embodiment, a
method copies only a subset of the backup data onto at least one computer-readable
duplicate backup storage medium as duplicate backup data so that the duplicate
backup storage medium is not an exact duplicate of the at least one backup storage
medium. For example, in one embodiment, in which the backup data includes a plurality
of work items, a subset of the work items are copied onto the at least one duplicate
backup storage medium. Method and apparatus for restoring backup data of interest
from duplicate backup storage media are also disclosed.