Abstract: A host library controller employs a plurality of ports for establishing a plurality of communication paths from the host library controller to a medium changer library. The host library controller further employs a processor and a memory storing instructions for the processor to issue a command from a medium changer command set, and to select one or more of the ports for communicating the medium changer command to the medium changer library depending on a command processing status of each port.

Abstract: Methods and apparatus are provided for dynamically compressing categories in a data storage library. In one embodiment, the method includes retrieving an identification of a first category in the data storage library, the first category being a last-compressed category. Next, an identification number of a first order of the first category is retrieved, the first order being a last compressed order. Compression is resumed of orders in the first category with an order next following the first order and continued with additional orders in the first category. If a predetermined amount of time has elapsed, the identification of the first category and the identification number of the order of the first category being compressed are stored. If, however, the predetermined amount of time has not elapsed and compression of the first category is complete, compression of a second category is begun.

Abstract: A storage system or subsystem, method of locating components in the storage system and program product therefor. Storage system components have fiducial marks identifying component location. A sensor is located at an expected fiducial location and a first pass search for the fiducial is conducted along a search path. A second pass search, if needed, begins at a position located, horizontally, between the first pass start position and the system accessor home location.