Abstract: Protection against data overwrite of a rewritable non-WORM data storage cartridge is provided by a data storage drive operating cartridge data overwrite protection procedures independent of, or not withstanding, the absence of cartridge controls relating to data overwrite protection. Also for the non-WORM cartridge, the drive responds to an allow data overwrite command to allow an immediately subsequent write type command to write to the cartridge even if the write command overwrites existing data. The overwrite protection procedures and data overwrite procedures may be configured and enabled for the data storage drive.

Abstract: Timing based servo bursts of servo frames, in which the frames are arranged to be symmetric with the same number of servo stripes in each burst of a frame, are synchronized by shifting selected bits. For example, servo frames are arranged with four servo bursts with an equal number of servo stripes in each burst, the servo frames comprising two symmetric sub-frames, each sub-frame comprising two bursts of servo stripes that are parallel to each other within a burst, and the bursts are non-parallel with respect to each other; each servo burst is arranged to comprise at least one reference servo stripe; and each servo burst is arranged to comprise at least one shifted servo stripe, wherein the shift is in the same longitudinal direction with respect to at least one reference servo stripe for each burst of a frame and the opposite longitudinal direction for bursts of sequentially adjacent frames.

Abstract: A tape head and bearing assembly comprises an air bearing structure having a tape bearing surface with a plurality of openings therein configured to provide a continuous air bearing of pressurized air to support a linear tape moving along a path, the air bearing being provided on only one side of the linear tape. A head slider assembly, such as an HDD-type assembly, is positioned at the opposite side of the linear tape from the tape bearing surface and is configured to be in contact with the linear tape.

Abstract: A servo detection system for detecting servo tracks of a longitudinal tape. In a read/write head, two servo read heads are spaced laterally on a first head module, and a servo read head is on a second head module spaced longitudinally from the first module. A method comprises initially sensing a tape servo track with one servo read head of the first module and the servo read head of the second module to determine skew misalignment of the servo track. A zero reference value is stored representing the determined skew misalignment. The detection system switches from the one servo read head of each module, to the two servo read heads of the first module, and employs the stored value to position the read/write head in the zero skew position. The two servo read heads are then employed to read two servo tracks to identify the data band and to control skew.

Abstract: Reuse of partially expired physical tape volumes reuse is attained in a longitudinal tape data storage drive, wherein data is stored as a sequence of serpentine wraps, a wrap comprising a first linear path traced on a longitudinal tape; and another linear path, laterally spaced from the first linear path, traced on the longitudinal tape; the linear paths extending from one end of the longitudinal tape to the opposite end and arranged in opposite directions. One embodiment of a method comprises identifying expired portions of stored data on the longitudinal tape; determining whether data of a complete linear path of the longitudinal tape has been expired; and allowing reuse of any determined complete linear path for storage of data.

Abstract: Methods, servo systems, and data storage drives follow the lateral shift excursions of longitudinal tape, for example, from flangeless tape guides. A servo sensor is configured to sense lateral position of a tape head with respect to longitudinal servo tracks of the tape, a fine actuator is configured to translate the head laterally, and a coarse actuator is configured to translate the fine actuator laterally. Position error is determined between the head and a desired position related to the servo track, and the fine actuator operated to translate the head laterally to reduce the position error. In the embodiment, lateral shift excursion is sensed from the position error, and the coarse actuator is positioned substantially at a midpoint of the lateral shift excursion. Thus, the fine actuator follows the lateral shift excursions, while the coarse actuator remains at the midpoint.

Abstract: Common sample timing control for sample timing of multiple read channels, wherein the signal clocking of the signals received by the multiple read channels are correlated, for example from parallel tracks of magnetic tape that have been written simultaneously. In one embodiment, a common sample timing control comprises multiple phase error inputs, each indicating phase error of one of the read channels. Logic responsive to the multiple phase error inputs is configured to weight and crosscouple the phase error indication of each phase error input with the phase error indication of each other phase error input, and to apply gain related to the variance of noise of the phase error indications. Feedback logic is responsive to the crosscoupling and is configured to provide a sample timing phase estimate for each read channel.

Abstract: As the result of a tape stick condition of magnetic tape with respect to a tape head, the supply reel and the take-up reel apply a base tension to the magnetic tape therebetween of substantially less than a full tension that occurs when the tape is running, and one reel varies the applied tension greater than and less than the base tension by an amount less than the base tension. The variation of the applied tension comprises first applying the greater tension and in succession, second, applying the less tension, comprising a whip effect. The whip effect may be in accordance with a sine wave. The varied tension is less than the base tension to maintain positive tension.

Abstract: A method, system and program are disclosed for efficiently processing host data which comprises encrypted and non-encrypted data and is to be written to a storage medium. The encrypted data is written to the storage medium in encrypted form. The non-encrypted data is encrypted by a storage device using a well known encryption key and written to the storage medium. In this way, the data that is processed by the storage device to and from the storage medium can always be processed through a single encryption engine.

Abstract: A data storage enclosure management system of a plurality of service processors is configured to communicate externally via a pair of FC-AL loops. Lead and subsidiary service processors are defined and lead service processors connect to ones of the FC-AL loops with an FC-AL address, and the lead and subsidiary service processors are connected by a secondary communication link. The lead service processor(s) employ an identifier unassociated with the FC-AL address to differentiate communications of the lead service processor from communications of an associated subsidiary service processor, the lead service processor serving as a proxy for the associated subsidiary service processor with respect to the FC-AL address and communicating with the associated subsidiary service processor via the secondary communication link.

Abstract: Non volatile storage may be employed to temporarily store data which is destaged to data storage drives. The non volatile storage is configured to preserve the data through a power outage. Some data may be preserved, but is not needed, such as the result of a failover to another non volatile storage. This unneeded data is tested to verify the non volatile storage by indicating whether the data survived the power cycle from full power to self refresh mode battery power to full power, without risking the loss of data that is needed.

Abstract: Methods, magnetic tape data storage drives, data storage systems, and magnetic tape data storage cartridges. A system having at least one magnetic tape data storage drive is configured to handle a magnetic tape cartridge comprising a magnetic tape data storage media and accompanying cartridge memory. The magnetic tape media comprises a plurality of longitudinal servo bands, the servo bands separated by data bands. Two servo bands, each at opposite sides of a data band are sensed. In response to at least one servo detection error signal of one of the two servo bands, an edge stress signal is set to the cartridge memory of the magnetic tape cartridge. Then, for example, after reloading the cartridge, the cartridge memory is inspected for a set edge stress signal; and, if the edge stress signal is set, only read operations are allowed with respect to the inspected magnetic tape data storage cartridge.

Abstract: Consistency for replicating data storage subsystem configurations in accordance with a “golden” configuration file. A data storage subsystem comprises a blade system configured to support a plurality of blades and a storage system, each arranged in a predetermined slot of the blade system, and at least one zoneable switch whose zoning is disabled at power on. A management module operates the blade system to power on all slots. The storage system, in accordance with a “golden” configuration file, transfers port enablement sequencing to the switch, and the switch enables and zones ports in sequence to allow the server blades to see the storage system in accordance with the port enablement sequence. The storage system is configured with the “golden” configuration file to log on the server blades in accordance with the port enablement sequence to logically configure the server blades in accordance with the “golden” configuration file.

Abstract: A data storage cartridge comprises data storage media configured to store data for read and/or write access, wherein the data may be arranged in a plurality of partitions; and a plurality of cartridge memories. A control system, for example of a data storage drive, is configured to allocate at least portions of capacity of the data storage media to cartridge memories of the data storage cartridge; and to provide information defining the allocated portions of capacity to the cartridge memories. Each of the cartridge memories may have a separate user and thus provide access for that user to separate partitions.

Abstract: A data storage cartridge comprises data storage media configured to store data for read and/or write access, wherein the data may be arranged in a plurality of partitions; and a plurality of cartridge memories. A control system, for example of a data storage drive, is configured to allocate at least portions of capacity of the data storage media to cartridge memories of the data storage cartridge; and to provide information defining the allocated portions of capacity to the cartridge memories. Each of the cartridge memories may have a separate user and thus provide access for that user to separate partitions.

Abstract: A computer program product for operating an automated data storage library with storage shelves, data storage drive(s), a bus bar; and a robot accessor with a drive system for moving the robot accessor, an accessor communication interface, a bus bar relay configured to engage and disengage the bus bar; a robot control configured to operate the drive system to move the robot accessor, to operate the picker, to operate the bus bar relay to engage the bus bar when the robot accessor is stationary; and a power storage system configured to receive power via the bus bar relay when the bus bar relay engages the bus bar, to store the received power, and to deliver the stored power to the robot accessor at least when the bus bar relay is disengaged.

Abstract: A computer program product for operating an automated data storage library with storage shelves, data storage drive(s), a bus bar; and a robot accessor with a drive system for moving the robot accessor, an accessor communication interface, a bus bar relay configured to engage and disengage the bus bar; and a robot control configured to operate the drive system to move the robot accessor, to operate a picker, and to operate the bus bar relay to engage the bus bar when the robot accessor is stationary, to provide communication capability with a library communication interface via the bus bar relay and the bus bar when the bus bar relay engages the bus bar. Additionally, a second communication system may be provided between the robot accessor and the automated data storage library, which is operable at least when the robot accessor is moving.

Abstract: Consistency for replicating data storage subsystem configurations in accordance with a “golden” configuration file. A data storage subsystem comprises a blade system with a plurality of slots, the blade system configured to support a plurality of blades and a storage system, each arranged in a predetermined slot of the blade system. A management module operates the blade system to first power on the storage system, and subsequently to power on the plurality of server blades in a sequential order that matches a blade system natural boot sequence order, skipping the storage system, and the storage system is configured with the “golden” configuration file to log on the server blades in accordance with the power on sequence to logically configure the server blades in accordance with the “golden” configuration file.

Abstract: A tape head and bearing assembly comprises an air bearing structure having a tape bearing surface with a plurality of openings therein configured to provide a continuous air bearing of pressurized air to support a linear tape moving along a path, the air bearing being provided on only one side of the linear tape. A head slider assembly, such as an HDD-type assembly, is positioned at the opposite side of the linear tape from the tape bearing surface and is configured to be in contact with the linear tape.

Abstract: Consistency for replicating data storage subsystem configurations in accordance with a “golden” configuration file. A data storage subsystem comprises a blade system with a plurality of slots, the blade system configured to support a plurality of blades and a storage system, each arranged in a predetermined slot of the blade system. A management module operates the blade system to first power on the storage system. In accordance with a “golden” configuration file, the storage system passes sequence information to the management module. The management module powers on the plurality of server blades in accordance with the sequence information. The storage system is configured with the “golden” configuration file to log on the server blades in accordance with the power on sequence to logically configure the server blades in accordance with the “golden” configuration file.