Abstract: Various embodiments of a tape storage system having a physical control unit configured to support multiple logical control units are provided. Each logical control unit supports communication with a single tape drive model type up to a maximum number of drives. A customer obtains a number N of logical control units through purchase, lease or other legitimate avenues. Based on the number of tape drive model types L and the number of tape drives for each type QL, the model types are mapped to the N LCUs. In general, mapping priority is given to the newer generation model types and the model types in which the number of attached tape drives QL exceeds the capacity M of a single LCU.

Abstract: Various embodiments of a tape storage system having a physical control unit configured to support multiple logical control units are provided. Each logical control unit supports communication with a single tape drive model type up to a maximum number of drives. A customer obtains a number N of logical control units through purchase, lease or other legitimate avenues. Based on the number of tape drive model types L and the number of tape drives for each type QL, the model types are mapped to the N LCUs. In general, mapping priority is given to the newer generation model types and the model types in which the number of attached tape drives QL exceeds the capacity M of a single LCU.

Abstract: A tape storage system having a physical control unit configured to support multiple logical control units is provided. Each logical control unit supports communication with a single tape drive model type up to a maximum number of drives. A customer obtains a number N of logical control units through purchase, lease or other legitimate avenues. Based on the number of tape drive model types L and the number of tape drives for each type QL, the model types are mapped to the N LCUs. In general, mapping priority is given to the newer generation model types and the model types in which the number of attached tape drives QL exceeds the capacity M of a single LCU. An exception being that the oldest model type is ensured a mapping to an LCU. The LCUs may be reconfigured and the model types remapped on the physical CU if the customer adds different model types to the storage system or obtains a different number of LCUs.

Abstract: In one embodiment, a product includes a magnetic medium having written thereon data in a data track. The data includes encrypted data written over unencrypted data. An indicator of a physical position on the magnetic medium that corresponds to an end of the encrypted data is stored on the product. A product according to another embodiment includes a magnetic medium having written thereon data in a data track. The data includes encrypted data written over unencrypted data. A portion of the unencrypted data is located before the encrypted data on the medium. An indicator of a physical position on the magnetic medium that corresponds to a beginning of the encrypted data is stored on the product.

Abstract: A tape storage system having a physical control unit configured to support multiple logical control units is provided. Each logical control unit supports communication with a single tape drive model type up to a maximum number of drives. A customer obtains a number N of logical control units through purchase, lease or other legitimate avenues. Based on the number of tape drive model types L and the number of tape drives for each type QL, the model types are mapped to the N LCUs. In general, mapping priority is given to the newer generation model types and the model types in which the number of attached tape drives QL exceeds the capacity M of a single LCU. An exception being that the oldest model type is ensured a mapping to an LCU. The LCUs may be reconfigured and the model types remapped on the physical CU if the customer adds different model types to the storage system or obtains a different number of LCUs.

Abstract: In one embodiment, a product includes a magnetic medium having written thereon data in a data track. The data includes encrypted data written over unencrypted data. An indicator of a physical position on the magnetic medium that corresponds to an end of the encrypted data is stored on the product. A product according to another embodiment includes a magnetic medium having written thereon data in a data track. The data includes encrypted data written over unencrypted data. A portion of the unencrypted data is located before the encrypted data on the medium. An indicator of a physical position on the magnetic medium that corresponds to a beginning of the encrypted data is stored on the product.

Abstract: In one embodiment, a system includes a processor and logic integrated with and/or executable by the processor, the logic being configured to: determine a physical position on a magnetic medium that corresponds to an end of an encrypted data set; store an indicator of the physical position on the magnetic medium and/or a memory coupled thereto; and cause obscuring of an unencrypted data set positioned after the physical position without overwriting the encrypted data set. In another embodiment, a computer program product includes a computer readable storage medium and program instructions embodied therewith, the program instructions readable and/or executable by the processor to cause the processor to: read an indicator of a physical position on a magnetic medium that corresponds to an end of an encrypted data set; and cause obscuring of an unencrypted data set positioned after the physical position without overwriting the encrypted data set.

Abstract: Method embodiments for facilitating configuration of a physical control unit to support multiple logical control units are provided. Each logical control unit supports communication with a single tape drive model type up to a maximum number of drives. A customer obtains a number N of logical control units through purchase, lease or other legitimate avenues. Based on the number of tape drive model types L and the number of tape drives for each type QL, the model types are mapped to the N LCUs. In general, mapping priority is given to the newer generation model types and the model types in which the number of attached tape drives QL exceeds the capacity M of a single LCU. An exception being that the oldest model type is ensured a mapping to an LCU. The LCUs may be reconfigured and the model types remapped on the physical CU if the customer adds different model types to the storage system or obtains a different number of LCUs.

Abstract: A method according to one embodiment includes outputting a first alert when a cache free space size is less than a first threshold and entering into a warning state, and outputting a second alert when the cache free space size is less than a second threshold and entering into a critical state. At least one scratch volume is deleted when in the critical state, the scratch volume chosen based on at least one of: a length of time the scratch volume has been designated scratch, a priority level of the information stored on the scratch volume, and a scratch delay value associated with the scratch volume.

Abstract: A method according to one embodiment includes outputting a first alert when a cache free space size is less than a first threshold and entering into a warning state, and outputting a second alert when the cache free space size is less than a second threshold and entering into a critical state. At least one scratch volume is deleted when in the critical state, the scratch volume chosen based on at least one of: a length of time the scratch volume has been designated scratch, a priority level of the information stored on the scratch volume, and a scratch delay value associated with the scratch volume.

Abstract: In one embodiment, a system includes a processor and logic integrated with and/or executable by the processor, the logic being configured to: determine a physical position on a magnetic medium that corresponds to an end of an encrypted data set; store an indicator of the physical position on the magnetic medium and/or a memory coupled thereto; and cause obscuring of an unencrypted data set positioned after the physical position without overwriting the encrypted data set. In another embodiment, a computer program product includes a computer readable storage medium and program instructions embodied therewith, the program instructions readable and/or executable by the processor to cause the processor to: read an indicator of a physical position on a magnetic medium that corresponds to an end of an encrypted data set; and cause obscuring of an unencrypted data set positioned after the physical position without overwriting the encrypted data set.

Abstract: According to one embodiment, a system includes a virtual tape library having a cache, a virtual tape controller (VTC) coupled to the virtual tape library, and an interface for coupling multiple hosts to the VTC. The cache is shared by the multiple hosts, and a common view of a cache state, a virtual library state, and a number of write requests pending is provided to the hosts by the VTC. In another embodiment, a method includes receiving data from at least one host using a VTC, storing data received from all the hosts to a cache using the VTC, sending an alert to all the hosts when free space is low and entering into a warning state, sending another alert to all the hosts when free space is critically low and entering into a critical state while allowing previously mounted virtual drives to continue normally.

Abstract: According to one embodiment, a method for managing cache space in a virtual tape controller includes receiving data from at least one host using the virtual tape controller; storing data received from the at least one host to a cache using the virtual tape controller; sending a first alert to the at least one host when a cache free space size is less than a first threshold and entering into a warning state using the virtual tape controller; sending a second alert to the at least one host when the cache free space size is less than a second threshold and entering into a critical state using the virtual tape controller; and allowing previously mounted virtual drives to continue normal writing activity when in the critical state.

Abstract: In one embodiment, a system includes a processor, logic in the processor and/or memory configured to determine a physical position on a magnetic medium that corresponds to an end of encrypted data written over residual unencrypted data, and logic configured to store an indicator of the physical position on at least one of the magnetic medium and a memory coupled thereto. In another embodiment, a method includes determining a physical position on a magnetic medium that corresponds to an end of encrypted data written over residual unencrypted data, storing an indicator of the physical position on at least one of the magnetic medium and a memory coupled thereto.

Abstract: Method embodiments for facilitating configuration of a physical control unit to support multiple logical control units are provided. Each logical control unit supports communication with a single tape drive model type up to a maximum number of drives. A customer obtains a number N of logical control units through purchase, lease or other legitimate avenues. Based on the number of tape drive model types L and the number of tape drives for each type QL, the model types are mapped to the N LCUs. In general, mapping priority is given to the newer generation model types and the model types in which the number of attached tape drives QL exceeds the capacity M of a single LCU. An exception being that the oldest model type is ensured a mapping to an LCU. The LCUs may be reconfigured and the model types remapped on the physical CU if the customer adds different model types to the storage system or obtains a different number of LCUs.

Abstract: According to one embodiment, a system includes a virtual tape library having a cache, a virtual tape controller (VTC) coupled to the virtual tape library, and an interface for coupling multiple hosts to the VTC. The cache is shared by the multiple hosts, and a common view of a cache state, a virtual library state, and a number of write requests pending is provided to the hosts by the VTC. In another embodiment, a method includes receiving data from at least one host using a VTC, storing data received from all the hosts to a cache using the VTC, sending an alert to all the hosts when free space is low and entering into a warning state, sending another alert to all the hosts when free space is critically low and entering into a critical state while allowing previously mounted virtual drives to continue normally.

Abstract: According to one embodiment, a system includes a virtual tape library having a cache, a virtual tape controller (VTC) coupled to the virtual tape library, and an interface for coupling at least one host to the VTC. The cache is shared by all the hosts, and a common view of a cache state, a virtual library state, and a number of write requests pending is provided to all the hosts by the VTC.

Abstract: A system according to one embodiment includes a processor; logic in the processor and/or a memory configured to determine a furthest physical position on a magnetic medium that unobscured data has been written to; and logic configured to store an indicator of the furthest physical position on at least one of the magnetic medium and a memory coupled thereto. A system according to another embodiment includes a processor; logic in the processor and/or a memory configured to receive an instruction to obscure data on a magnetic medium; logic configured to read an indicator of a furthest physical position on the magnetic medium that unobscured data has been written to; and logic configured to cause obscuring of the unobscured data on the magnetic medium, and terminating the obscuring upon reaching the physical position in the indicator.

Abstract: In one embodiment, a system includes a processor, logic in the processor and/or memory configured to determine a physical position on a magnetic medium that corresponds to an end of encrypted data written over residual unencrypted data, and logic configured to store an indicator of the physical position on at least one of the magnetic medium and a memory coupled thereto. In another embodiment, a method includes determining a physical position on a magnetic medium that corresponds to an end of encrypted data written over residual unencrypted data, storing an indicator of the physical position on at least one of the magnetic medium and a memory coupled thereto.

Abstract: A system according to one embodiment includes a processor; logic in the processor and/or a memory configured to determine a furthest physical position on a magnetic medium that unobscured data has been written to; and logic configured to store an indicator of the furthest physical position on at least one of the magnetic medium and a memory coupled thereto. A system according to another embodiment includes a processor; logic in the processor and/or a memory configured to receive an instruction to obscure data on a magnetic medium; logic configured to read an indicator of a furthest physical position on the magnetic medium that unobscured data has been written to; and logic configured to cause obscuring of the unobscured data on the magnetic medium, and terminating the obscuring upon reaching the physical position in the indicator.