Abstract: The present invention is a system and method which allows for a VTL system that supports thin provisioning to implicitly unmap unused storage. Such unmap operations may occur even though the VTL system does not receive any explicit unmap requests from its initiators. For example, if a system administrator knows that once a virtual tape drive of the VTL system has been partially overwritten, all previously written data sets on that virtual tape drive will never again be accessed, the system administrator may configure the VTL system so that it unmaps the entire remainder of the virtual tape drive on the first data overwrite.

Abstract: A method for communication between an initiator system and a block storage cluster may include receiving a first command at a first storage system included in a plurality of storage systems of the block storage cluster. The method may also include transmitting a referral response from the first storage system to the initiator system when at least a portion of the data associated in the first command is stored by a second storage system. The method may further include obtaining a segment start value and a corresponding port identifier based on the referral response, and directing a second command to at least a second storage system included in the plurality of storage systems of the block cluster.

Abstract: A system and method for root booting includes a plurality of computing devices that each boot from a read-only base volume of an attached storage device that includes data common to the computing devices. The attached storage device also includes a plurality of volumes, each dedicated to one of the computing devices, which are redirect on write snapshots of the read-only base volume including unique items for the respective computing device. The read-only base volume may be stored in one or more solid state drives which may be configured as a RAID (redundant array of independent disks) and/or mirrored with one or more other storage drives. The plurality of volumes may each be stored in one or more hard disk drives which may be configured as a RAID. The attached storage device may be operable to add common data to the read-only base volume.

Abstract: A method for communication between an initiator system and a block storage cluster may include receiving a first input/output (I/O) request from the initiator system. The method may also include sending a referral response from a first storage system included in a plurality of storage systems of the block storage cluster to the initiator system when data associated with the first I/O request is stored in more than one storage system of the plurality of storage systems of the block storage cluster. Additionally, the method may include directing a referral I/O to the first storage system and the second storage system for transferring data to or transferring data from the first storage system and the second storage system, and transferring data associated with the referral I/O to or transferring data associated with the referral I/O from the first storage system and the second storage system.

Abstract: The present invention is a method for drive management and data placement in an archival storage system having a set of drives. The method includes mapping redundant data stripes onto the drives. A first active data stripe, located on a first subset of the drives, is then selected from the mapped data stripes. The first subset is placed into a normal power state and a second subset of the drives is placed into a low power state. Data is then written to the first active data stripe. Before the first active data stripe is fully used, the method includes selecting a next active/second active data stripe from the mapped data stripes, the second active data stripe being at least partially located on the second subset. The method may be performed by a system which implements MAID techniques for drive management and CRUSH for data placement.

Abstract: The present invention is a system and method which allows for a VTL system that supports thin provisioning to implicitly unmap unused storage. Such unmap operations may occur even though the VTL system does not receive any explicit unmap requests from its initiators. For example, if a system administrator knows that once a virtual tape drive of the VTL system has been partially overwritten, all previously written data sets on that virtual tape drive will never again be accessed, the system administrator may configure the VTL system so that it unmaps the entire remainder of the virtual tape drive on the first data overwrite.

Abstract: The present invention is a method for drive management and data placement in an archival storage system having a set of drives. The method includes mapping redundant data stripes onto the drives. A first active data stripe, located on a first subset of the drives, is then selected from the mapped data stripes. The first subset is placed into a normal power state and a second subset of the drives is placed into a low power state. Data is then written to the first active data stripe. Before the first active data stripe is fully used, the method includes selecting a next active/second active data stripe from the mapped data stripes, the second active data stripe being at least partially located on the second subset. The method may be performed by a system which implements MAID techniques for drive management and CRUSH for data placement.

Abstract: The present invention is a method for utilizing mirroring in a data storage system to promote improved data accessibility and improved system efficiency. The method includes establishing a first set of drives of the system in active mode and a second set of drives of the system in passive mode (ex.—a lower power mode). The method further includes writing a first portion of data to a first drive of the first drive set, and writing a copy of the first portion of data to a second drive of the first drive set. A third drive (ex.—from the second drive set), may be activated from passive mode to active mode. The method may further include writing a second copy of the first data portion to the third drive, re-establishing the third drive in passive mode, and deleting the copy of the first data portion from the second drive.

Abstract: A method for communication between an initiator system and a block storage cluster may include receiving a first command at a first storage system included in a plurality of storage systems of the block storage cluster. The method may also include transmitting a referral response from the first storage system to the initiator system when at least a portion of the data associated in the first command is stored by a second storage system. The method may further include obtaining a segment start value and a corresponding port identifier based on the referral response, and directing a second command to at least a second storage system included in the plurality of storage systems of the block cluster.

Abstract: A method for communication between an initiator system and a block storage cluster may include receiving a first input/output (I/O) request from the initiator system. The method may also include sending a referral response from a first storage system included in a plurality of storage systems of the block storage cluster to the initiator system when data associated with the first I/O request is stored in more than one storage system of the plurality of storage systems of the block storage cluster. Additionally, the method may include directing a referral I/O to the first storage system and the second storage system for transferring data to or transferring data from the first storage system and the second storage system, and transferring data associated with the referral I/O to or transferring data associated with the referral I/O from the first storage system and the second storage system.

Abstract: The present invention is a method for storing data. The method includes the step of dividing data into a plurality of uniformly-sized segments. The method further includes storing said uniformly-sized segments on a plurality of storage mechanisms. The method includes the steps of monitoring access to the uniformly-sized segments stored on the plurality of storage mechanisms to determine an access pattern; monitoring access patterns between the plurality of disks and monitoring performance characteristics of the plurality of storage mechanisms to determine a performance requirement for the plurality of storage mechanisms. Finally, the method includes the step of migrating at least one segment of the plurality of uniformly-sized segments from a first storage mechanism of the plurality of storage mechanisms to a second storage mechanism of the plurality of storage mechanisms in response to at least one of the access patterns or the performance requirements.

Abstract: A system and method for root booting includes a plurality of computing devices that each boot from a read-only base volume of an attached storage device that includes data common to the computing devices. The attached storage device also includes a plurality of volumes, each dedicated to one of the computing devices, which are redirect on write snapshots of the read-only base volume including unique items for the respective computing device. The read-only base volume may be stored in one or more solid state drives which may be configured as a RAID (redundant array of independent disks) and/or mirrored with one or more other storage drives. The plurality of volumes may each be stored in one or more hard disk drives which may be configured as a RAID. The attached storage device may be operable to add common data to the read-only base volume.

Abstract: A system and method for communication amongst a device and multiple controllers. A controller may use a direct communication path to the device or may route the communication to another controller that has a faster communication path to the device. Such a system and method is particularly useful when the device takes a long time to switch from a communication path with the second controller to a communication path with the first controller.