This data storage subsystem creates multiple virtual storage devices on demand, which are available to any and all of the system's host data processors. The subsystem utilizes a plurality of tape devices and automated tape libraries with the tape devices connected to a plurality of data processors via a high-speed network. A set of software components, the Network Storage Manager (NSM) controls all system operations. Depending upon the requested storage performance, one or more tape devices are assigned to a virtual device. Data stripping across multiple tape devices allows the storage bandwidth of a virtual device to be changed on demand. The overall capacity and performance of the subsystem is scalable by adding or removing storage devices. The NSM system controller contains a plurality of software elements including: Resource Allocation, Resource Configuration, Resource Management, and Security Management modules. The use of a networked storage manager enables the storage devices to be managed as a pool and yet be attached directly to the network as individual resources. The NSM also provides the mechanism for the enterprise management to control tape device allocation and configuration as well as other functions, such as tape cartridge movement, data migration and data security.

Network attached virtual tape data storage subsystem

A modular computer storage system and method is provided for managing and directing data archiving functions, which is scalable and comprehends various storage media as well as diverse operating systems on a plurality of client devices. A client component is associated with one or more client devices for generating archival request. A file processor directs one or more storage devices, through one or more media components, which control the actual physical level backup on various storage devices. Each media component creates a library indexing system for locating stored data. A management component coordinates the archival functions between the various client components and the file processor, including setting scheduling policies, aging policies, index pruning policies, drive cleaning policies, configuration information, and keeping track of running and waiting jobs.

Modular backup and retrieval system used in conjunction with a storage area network

A method for enabling access to a data resource, which is held on a file server (25) on a first local area network (LAN) (21a), by a client (28) on a second LAN (21b). A proxy receiver (48) on the second LAN (21b) intercepts a request for the data resource submitted by the client (28) and transmits a message via a wide area network (WAN) (29) to a proxy transmitter (52) on the first LAN (21a), requesting the data resource. The proxy transmitter (52) retrieves a replica of the data resource from the file server (25) and conveys the replica of the data resource over the WAN (29) to the proxy receiver (48), which serves the replica of the data resource from the proxy receiver (48) to the client (28) over the second LAN (21b).

Virtual file-sharing network

A method for enabling access to a data resource, which is held on a file server ( 25 ) on a first local area network (LAN) ( 21 a ), by a client ( 28 ) on a second LAN ( 21 b ). A proxy receiver ( 48 ) on the second LAN ( 21 b ) intercepts a request for the data resource submitted by the client ( 28 ) and transmits a message via a wide area network (WAN) ( 29 ) to a proxy transmitter ( 52 ) on the first LAN ( 21 a ), requesting the data resource. The proxy transmitter ( 52 ) retrieves a replica of the data resource from the file server ( 25 ) and conveys the replica of the data resource over the WAN ( 29 ) to the proxy receiver ( 48 ), which serves the replica of the data resource from the proxy receiver ( 48 ) to the client ( 28 ) over the second LAN ( 21 b ).

Double-proxy remote data access system

The invention relates generally to archiving data items in an information store. More particularly, the invention provides a computerized method for identifying, in a first information store, a first data item satisfying retention criteria; copying the first data item to a second information store; creating, in the first information store, a second data item containing a subset of the data of the first data item selected based on the data type of the first data item; and replacing the first data item, in the first information store, with the second data item.

System and method for archiving objects in an information store

A method and system for efficiently importing/exporting a removable storage volume having a number of data files from a first virtual storage system to a second virtual storage system. The method includes writing a table of contents to the end of the removable storage volume in the first virtual storage system. The table of contents uniquely identifies the data files residing in the removable storage volume. Next, the removable storage volume is transferred to the second virtual storage system. Upon receipt of the removable storage volume, the second virtual storage system updates a database in the second virtual storage system utilizing the information contained in the table of contents without having to read each of the data files in the removable storage volume. In a related embodiment, for each of the data file in the removable storage volume, the table of contents includes a filename, starting record on the removable storage volume and number of records in the data file.

Method and system for efficiently importing/exporting removable storage volumes between virtual storage systems

A virtual data storage system provides a method and apparatus for adaptively throttling transfers into a cache storage to prevent an overrun in the cache storage. The virtual data storage system includes a storage interface appearing as a set of addressable, virtual storage devices, a cache storage for initially storing host-originated data files, storage devices for eventually storing the data files on a set of storage volumes, and a storage manager for directing the data files between the cache storage and the storage devices. An amount of available space in the cache storage, or a cache free space, is monitored against an adjustable cache space threshold. A storage throttle is computed when the cache free space drops below the cache space threshold. Additionally, a recall throttle is computed based on the cache free space and a number of storage devices reserved for recalling data files from the set of storage volumes. A maximum value of the storage throttle and the recall throttle is used to delay the storing of data files and the recalling of data files into the cache storage and to prevent overrunning the cache storage by completely depleting the cache free space.

Virtual data storage system with an overrun-resistant cache using an adaptive throttle based upon the amount of cache free space

Virtual data storage cartridges are created on a data storage subsystem to/from which volume writes and reads are directed. When a number of data volumes have been written, the controller may migrate them to the tape drive, a much faster process than writing directly to tape and enabling multiple logical volumes to be written to a single physical tape. With the present invention, virtual scratch cartridges are virtually premounted in a virtual drive loader while the virtual drive is accessing another virtual cartridge. When the host calls for a new scratch cartridge, it can be mounted in the virtual drive almost immediately, having already been virtually pre-loaded.

Virtual integrated cartridge loader for virtual tape storage system

A transaction processing system that continues to process incoming transactions during the failure and recovery of either of two duplicate databases. One of the two duplicate databases is assigned “active” status and the other is maintained with “redundant” status. All incoming queries are sent only to the active database and all incoming updates are sent to both active and redundant databases. When one database fails, the other is immediately reassigned active status if not already active and continues to process incoming queries and updates during the failure. When the failed database is repaired and restarted, all records are flushed therefrom and the failed database is reconstructed using interleaved copy and update operations in a single pass through the active database. Incoming transaction and copy operations are interleaved according to a queue thresholding method for throttling copy operations responsive to increased numbers of incoming transactions. The transaction processing system remains operational both during the failure and during the recovery activities and reaches full recovery without downtime.

Redundant database recovery through concurrent update and copy procedures

A portion of digital data records are stored on a direct access storage device (DASD) in emulation of sequential-access media when the parent digital data records are transferred to a sequential-access media. The efficiency of storage and access to the data portion is improved by random-access recall of the data in the data portion, and by constructing a data portion trailer containing various statistics about the records for referencing the digital data and advancing to target data. The volume data portion trailer is constructed as read forward and forward space block operations are performed. Data is preferably stored in logically assembled records. Interspersed with the records, there may be one or more marker codes, which function like tape marks among the various data records. The volume trailer may contain pointers to each record, a record count and marker codes for the data portion. Statistics contained in the data portion trailer enable substantially more efficient access of the data by a DASD.

Wayne Charles Carlson

Papers

Method and system for efficiently importing/exporting removable storage volumes between virtual storage systems

Virtual data storage system with an overrun-resistant cache using an adaptive throttle based upon the amount of cache free space

Virtual integrated cartridge loader for virtual tape storage system

Redundant database recovery through concurrent update and copy procedures

Storage and access to scratch mounts in VTS system