Abstract: In a storage server on a storage area network, a media unit manager manages disk space in a manner transparent to the host computers. The media unit manager uses media units corresponding to the physical storage devices on the storage area network to build higher-level media units. The higher level media units can have the attributes of being sliced, concatenated, mirrored, striped, etc. Thus, the host computers need not be aware of the specific physical storage devices themselves, reducing the management and reconfiguration burden on the host computers when storage devices are added to or removed from the storage area network.