Patent ID: 7975101

Claim:
A storage medium storing a set of program instructions executable on a data processing device that is configured to be connected to a peripheral device having a plurality of storage units, the data processing device having an operating system that manages the plurality of storage units, the set of program instructions comprising: acquiring a number of at least one virtual unit with which at least one of the plurality of storage units is associated, the number of at least one virtual unit being set smaller than a total number of the plurality of storage units; receiving, from the operating system, a first command including a first logical unit number that specifies one of the at least one virtual unit; registering, as an accessible storage unit for a second logical unit number, a single storage unit from among the at least one of the plurality of storage units that is associated with the one of the at least one virtual unit specified by the first command, the single storage unit being in condition for communicating data with the data processing device; modifying the first command including the first logical unit number to a second command including the second logical unit number that specifies the accessible storage unit; and outputting the second command to the peripheral device so as to execute data communication with the accessible storage unit.