Storage Technology Corporation

International Business Machines Corporation

Christopher James West

Michael Steven Milillo

David Grant Beal

David Glenn Hostetter

David A Serls

Scott Adam States

Robert P Eskenberry

Theresa Lynn Segura

Michael Richard Crater

Peter H Tallman

Steven Christopher Fraioli

Jennifer Johnson

Michael S Kelly

A method and system for retrieving data that is stored on a backup or secondary storage system located at a remote location to a local storage system. Restoring of backup data involves the transferring of a point-in-time copy of primary system data from a secondary storage system to the local system. The point-in-time copy is created on the secondary system using an asynchronous remote copy scheme. The point-in-time copy that is restored may be either an entire volume or portions thereof.

Storage control system for restoring a remote data copy

A cache storage system and method are provided for saving storage space in a cache, the system and method for use in a data storage system having multiple storage devices and multiple virtual addresses, each virtual address having a data object associated therewith. Each data object is stored at a storage device location having a unique identifier. The cache storage system and method include a cache for storing a data object associated with at least one virtual address. For a first virtual address, the first virtual address data object is staged into the cache. For a second virtual address, a pointer is generated for use in pointing to the first virtual address data object staged in the cache when the storage device location identifier of the second virtual address data object matches the storage device location identifier of the first virtual address data object.

Cache storage system and method

A client-directed pre-stage operation of a cache memory used to access data blocks from a mass data storage device attached to a host computer through a channel control processor is provided by a method and apparatus comprising a channel control processor for retrieving data blocks from the mass storage device to be pre-staged within the cache memory, a channel interface coupled between the channel control processor and the host computer, a mass storage device interface coupled between the channel control processor and the mass storage device, and a cache memory coupled between the channel interface and the mass storage interface; the cache memory is further coupled to the cache control processor to provide the cache control processor access to data stored within the cache memory. The cache control processor receives a cache bitmap from the host computer to specify the data blocks from the mass storage device to be pre-staged into the cache memory. Each bit within the cache bitmap corresponds to a data block within the mass storage device which may be pre-staged into the cache memory.

System and method for providing client-directed staging to improve non-sequential access performance in a caching disk storage system

System and method for restoring data from secondary volume to primary volume in a data storage system

A storage system and method for storing delta difference data indicative of the differences between new data and old data. A data transferring unit has copies of old data and new data. The data transferring unit compares the new data with the old data to determine delta difference data indicative of the differences between the new data and the old data. A target storage device having a copy of the old data receives the delta difference data from the data transferring unit. The target storage device stores the delta difference data and may then determine the new data by merging the old data with the delta difference data. The target storage device transmits the determined new data to a data receiving unit upon request. The method and system may be used with peer-to-peer remote copy (PPRC) storage system and storage area network (SAN) storage system.

Method and system of storing a main data file and deltas in a storage device for determining new data files from the main data file and the deltas

Systems and methods are provided to backup, restore and relocate compressed data images, e.g., DASD compressed tracks, associated with virtual storage volumes. A compressed track image of the data is first stored in a storage volume. The data derives from a connected host connected with a control unit that manages the storage volume. When the host data is uncompressed, the control unit compresses the data. In backup, the host reads the compressed data with a read protocol and the control unit assigns metadata to the compressed track. The compressed track is then stored in a backup device, e.g., a tape drive. In restore, the host writes the compressed track to the control unit with a write protocol. If desired, the track is relocated to a different location or to a different storage volume through the associated metadata. In decompression, a seed value is assigned to the data to ensure identification across relocation.

Systems and methods for relocation of compressed data tracks

A system and method for synchronizing a data copy include in one embodiment first and second remote copy trios, each with source, target, and secondary volumes. Source volumes store initial data files, execute write commands to generate updated data files, and generate records of the write commands. Target volumes receive copies of the initial data files and the write command records, and transmit the copies of the initial data files and data indicated by the write command records to secondary volumes. Secondary volumes store the copies of the initial data files and the data indicated by the write command records, which are available for use in generating copies of the updated data files. The target volumes transmit to the secondary volumes in series relative to each other so that consistency is maintained at all times across the source volumes.

System and method for synchronizing a data copy using an accumulation remote copy trio consistency group

A method and system for automatically gathering information from different types of devices connected in a network when a device fails includes a network connecting a plurality of different types of devices which communicate with one another across the network. A network controller determines which devices in the network are capable of saving failure information during the time when one of the devices encounters an error. The network controller determines when one of the devices encounters an error. The network controller then gathers the failure information from the devices upon determining that one of the devices has encountered an error.

Method and system for automatically gathering information from different types of devices connected in a network when a device fails

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.

Method and apparatus for transferring data between a primary storage system and a secondary storage system using a bridge volume

A method and apparatus in a data processing system for copying data. A request is received to copy data from a first storage system to second storage system, wherein the request identifies a source volume on the first storage system and a target volume on the second storage system and wherein data is located on a first source volume in the first storage system. Data is transferred to a second source volume in the first storage system. A pair is automatically established between the second source volume and the target volume. The data for the request is copied from the second source volume to the target volume after the pair has been automatically established. The pair is terminated after the data has been copied to the target volume. The requester originating the request is notified of the result of the copy operation.

Method and apparatus for copying data from one storage system to another storage system

A method and system for transferring data from a primary storage system to a secondary storage system in which the primary storage system includes primary storage volumes and a primary bridge volume and the secondary storage system includes secondary storage volumes and a secondary bridge volume. A link between the primary bridge volume and the secondary bridge volume is established. The data to be transferred from a primary storage volume to a corresponding secondary storage volume is then copied onto the primary bridge volume by using pointers to the data of the primary storage volume (internal snapshot copy). Snapshot copied data is then transferred from the primary bridge volume to the secondary bridge volume over the link. The data is then moved from the secondary bridge volume to the secondary storage volume corresponding to the primary storage volume to put the primary storage volume and the corresponding secondary storage volume in synchronization. This process enables the use of bridge volumes to handle data synchronization responsibilities in addition to data transferring responsibilities thereby allowing the host to not have to compete for access to primary storage volumes.

Method and system for transferring data between primary storage and secondary storage using a bridge volume and an internal snapshot copy of the data being transferred

A storage control system and method for storing and retrieving data to and from a tape backup system that is located remotely from a primary host system. The primary system is coupled to a remote storage system for remote copy applications. The tape backup system is coupled to the remote storage system and operated at the remote site. Conducting control signals through the primary storage controller to the remote storage controller enables control over the tape backup system from the local or primary site. Data can be backed up to the tape system from the remote storage site which enables the local host to perform applications during the backup window. Data can also be restored from the tape system to the remote storage system and transferred back to the primary system via the communications link.

Storing and retrieving data on tape backup system located at remote storage system site

The present invention relates to a method for testing the operability of a Peer to Peer Remote Copy (PPRC) data storage system in disaster situations. A PPRC data storage system includes a host processor, a primary storage subsystem and a secondary storage subsystem where the secondary storage subsystem is coupled to the primary storage subsystem for mirroring of data therebetween. A command is sent from the host processor directing the primary storage subsystem to simulate a disaster. Upon detection of the disaster, the host establishes direct communication with the secondary storage subsystem, and validates the integrity of the system by comparing data from the secondary storage subsystem to data from the primary storage subsystem.

System and method for simulating disaster situations on peer to peer remote copy machines

A method and system for transferring difference data (delta) between new and old data from a data transferring unit to a storage device having a copy of the old data for enabling the storage device to determine the new data based on the old data and the transferred difference data and then store the new data in place of the old data. Both of the data transferring unit and the target storage device have a copy of the old data. When new data is written at the data transferring unit to modify the old data the data transferring unit compares the new data with the old data to determine the difference data. The difference data is indicative of the differences between the new data and the old data. The target storage device merges the old data with the difference data to determine the new data. Upon determining the new data the target storage device discards the old data and stores the new data. The method and system may be used with peer-to-peer remote copy (PPRC) storage systems and storage area network (SAN) storage systems.

Growing community of inventors

Boulder, CO, United States of America

Christopher James West