Abstract: A method and apparatus for reducing tape dimensional changes during accessing of a tape. A profile for the tape is identified. A determination is then made as to whether a location is being accessed on the tape. Tension applied to the tape is adjusted using the location and the profile, wherein tape width dimensional changes are minimized.

Abstract: A guide rail switch for a robotic track system is provided, the robotic track system comprising at least one horizontal guide rail, at least one vertical guide rail, and at least one robot that can move along the guide rails. The switch comprises a frame coupled to the horizontal guide rail and the vertical guide rail, and a moving joint coupled to the frame, wherein the moving joint can move between a first and second position. A first rail section is coupled to the moving joint, wherein the first track section connects to the horizontal guide rail when the moving joint is in the first position. A second rail section coupled to the moving joint, wherein the second track section connects to the vertical guide rail when the moving joint is in the second position. This switch allows the robot to move between the vertical and horizontal rail depending on which position the switch is in.

Abstract: A method and apparatus in an automated data storage library for identifying a location of a robot in the automated data storage library. Signals are transmitted from a set of transmitters in the automated data storage library, wherein a location of the set of transmitters is known. The signals transmitted from the set of transmitters are received at a receiver located on the robot to form a set of received signals. The location of the robot is determined using the set of received signals and the location of the set of transmitters.

Abstract: A method and apparatus for transferring data from a first storage system to a second storage system in which the first storage system includes a first plurality of storage devices and the second storage system includes a second plurality of storage devices. Data is transferred using a pair of devices selected for transferring data for all of the storage devices. Data to be transferred from source storage devices within the first plurality of storage devices is placed or queued on a selected primary storage device within the first plurality of storage devices. The data is sent to a selected secondary storage device within the plurality of storage devices. The data is relocated from the selected secondary storage device to target storage devices within the second plurality of storage devices.

Abstract: A method for using existing internal mapping mechanisms to dynamically map data in a computer storage subsystem is provided. The invention comprises using a dynamic mapping mechanism to mark (e.g., via a D-Mark) a data location and then using pointers to direct write requests for the data location to a side file. The new data is then written in the side file and a housekeeping operation reconciles the old and new data locations.

Abstract: An apparatus and method for writing and reading data to and from a virtual volume of redundant storage devices is provided. The apparatus and method make use of metadata identifying the number of data storage devices and number of parity storage devices in the virtual volume of redundant storage devices. In addition, other metadata, such as the identity of the data storage devices and parity storage devices may be utilized. The metadata is stored with each block written to each of the storage devices. In the event of a failure of a storage device, the metadata is modified to reflect the failure and the storage device to which the data intended for the failed storage device was written. In this way, if a failure of a storage device is encountered, each block in the virtual volume of redundant storage devices has enough information in the metadata to identify where to find the data that was intended for the failed storage device. Thus, reconstruction of data using parity information is not required.