Netapp, Inc.

Network Appliance, Inc.

Legato Systems, Inc.

Emc Corporation

Celio Corporation

Randall C Johnson

Roger Keith Stager

Craig Anthony Johnston

Pawan Saxena

Rico Blaser

Yafen Peggy Chang

Donald Alvin Trimmer

Richard S Ohran

Dan Price

Don Alvin Trimmer

Donald T Saxby

Colin Nb Cook

In a mobile device with a mobile device video driver that can be interdicted, such as a display telephone or PDA, a method and system for display on a remote video display device is provided involving forming an enhanced display image in an enhanced video frame buffer and reconstructing the display image in a duplicate enhanced video frame buffer in the remote video display device.

Method and apparatus for providing enhanced resolution display for display telephones and PDAs

A system for synchronizing a secondary volume with a primary volume in a continuous data protection system includes scanning means for scanning a region of the primary volume; comparing means for comparing the scanned region with a corresponding region of the secondary volume; storing means for storing an identification of the scanned region in a compare delta map when the comparing means returns a discrepancy between the scanned region and the corresponding region; copying means for copying data from the primary volume to the secondary volume, using the compare delta map as a guide to locate the data to copy; and revising means for revising the compare delta map by removing any changes made to the primary volume during a scan interval, which is a period of time required to scan the primary volume.

Method and system for restoring a volume in a continuous data protection system

A method for tracking changes on a primary volume in a continuous data protection system writes data to the primary volume. A copy of the data is written to a secondary volume, the secondary volume including all writes made to the primary volume. Each write made to the secondary volume is mapped in a data structure, such that the data structure tracks changes on the primary volume between two different points in time.

Method and system for storing data using a continuous data protection system

A method for synchronizing a secondary volume with a primary volume in a continuous data protection system begins by scanning a region of the primary volume, which is then compared with a corresponding region of the secondary volume. An identification of the scanned region is stored in a compare delta map when the comparison results in a discrepancy between the scanned region and the corresponding region. Data is copied from the primary volume to the secondary volume, using the compare delta map as a guide to locate the data to copy. If the data protection system has failed just prior to the restore process being initiated, it is termed a re-baseline, and the entire primary volume is scanned. If the data protection system is active prior to the restore process being initiated, it is termed a re-synchronization, and is optimized by scanning only select regions of the primary volume.

Method and system for synchronizing volumes in a continuous data protection system

A method and system where data is maintained in a continuous data protection system is disclosed. A primary volume may be protected according to an any-point-in-time (APIT) window wherein restores may be performed at any time as desired. The APIT window may be of any time duration as desired. Outside of the APIT window, a retention policy for phasing out data may be established as desired.

Method and system for maintaining data in a continuous data protection system

In a continuous data protection system having a primary volume and a secondary volume, a method for data recovery begins by selecting a snapshot of the primary volume to be recovered and a location on which the snapshot is to be loaded. A point in time (PIT) map is created for the selected snapshot, and the selected snapshot is loaded at the selected location. A data block from the PIT map is resolved to determine which block on the secondary volume is presented as being part of the snapshot. The snapshot is accessed via a host computer as if the snapshot was the primary volume at an earlier point in time, corresponding to the time of the selected snapshot.

Method and system for data recovery in a continuous data protection system

A method and system wherein data is structured so that writes may be continuously duplicated and a protected volume may be restored to a particular point in time as desired. Writes are continuously duplicated on a secondary volume and organized into delta maps. The delta maps indicate which memory blocks were written to during a particular time frame.

Recovering mirrored data after the failure of a computer using write requests stored in a delta queue of an associated computer without transmitting all of the mirrored data. A write request at a primary computer is stored in a delay buffer. A copy of the write request is transmitted to a backup computer and stored in a delta queue. The backup computer executes the copy of the write request and transmits acknowledgement of the receipt of the write request to the primary computer. In response to the acknowledgement, the primary computer executes the write request stored in the delay buffer. The computers then exchange subsequent acknowledgements of the write request execution, enabling the computers to delete the write requests. If the primary computer fails, the primary computer recovers data by receiving only the copies of write requests that remain stored in the delta queue of the backup computer.

Recovery of data using write request copies in delta queue

Obtaining mirrored data so that the original data can be recovered after failure without transmitting the entire mirrored data between computers. A write request at a primary computer is stored in a delay buffer and a copy is transmitted to a backup computer, where it is stored in a delta queue. The backup computer executes the copy of the write request to the mirrored data and transmits an acknowledgement to the primary computer that the copy of the write request has been received. In response to the acknowledgement, the primary computer executes the write request stored in the delay buffer. The computers send to each other subsequent acknowledgements of the write request execution, enabling the computers to delete the write requests. If the primary computer fails, the primary computer can recover the original data by receiving only the copies of write requests that remain stored in the delta queue.

Performing acknowledged operations on original and mirrored copies of data

A primary computer system and a backup computer system each have an associated memory. For each write request, a copy of the request is forwarded to a delay buffer and memory queue associated with the primary computer system, and a copy is forwarded to a memory queue of the backup computer system. The backup computer system transmits an acknowledgement signal to the primary computer system when the backup computer system receives its copy of the request. The write request in the delay buffer of the primary computer system is executed in the primary memory only upon receipt of this acknowledgement signal. Thus, the backup computer system knows of every request executed in the primary memory. The write request is executed in the backup memory at any time after the backup computer system receives the write request. The write requests are deleted from the memory queues (primary and backup) when the associated computer system confirms that the write request was executed in the memory of the opposite computer system. Should the primary (or backup) computer system shut down, the requests are accumulated in the opposite backup (or primary) memory queue. When the primary (or backup) computer system becomes operational again, the requests in the opposite backup (or primary) memory queue are executed in the primary (or backup) memory. Thus, no memory is lost when the primary (or backup) computer system shuts down and complete remirroring of data is not required.

Growing community of inventors

Pleasant Grove, UT, United States of America

Randall C Johnson