Donald L Hart

US Patent:

6408310, Jun 18, 2002

Filed:

Oct 8, 1999

Appl. No.:

09/415274

Inventors:

Donald Ralph Hart - Irvine CA

Assignee:

Unisys Corporation - Blue Bell PA

International Classification:

G06F 1730

US Classification:

707201, 707202, 707204, 709248, 714 12, 714 20

Abstract:

In order to correlate or synchronize the database of a source primary host with the backup database of a remote secondary host, the present method operates to speed up the transfer of audit blocks from primary host to secondary host when an out-of-sync signal indicates the secondary host audit blocks are not on a par with the primary host audit blocks. A Catchup process utilizes multiple buffers of audit blocks at the primary host which can then be asynchronously transferred, by a sequence of Catchup tasks, on a parallel concurrent operation, over to physical files of said secondary host.

US Patent:

6430577, Aug 6, 2002

Filed:

Oct 8, 1999

Appl. No.:

09/415273

Inventors:

Donald Ralph Hart - Irvine CA

Assignee:

Unisys Corporation - Blue Bell PA

International Classification:

G06F 1730

US Classification:

707201, 707 10, 707204, 709248, 714 20

Abstract:

In order to obviate data discrepancy between a primary source database and a secondary remote backup database, a Tracker program is used to sense the lack of synchronism between a primary audit file and secondary audit file. Then, a Catch-up program operates to transfer sectioned audit files from the primary to secondary in a parallel transfer mode until the primary and secondary audit files are accurate duplicates of each other, i. e. , they are now in synchronism.

US Patent:

6446090, Sep 3, 2002

Filed:

Oct 8, 1999

Appl. No.:

09/415333

Inventors:

Donald Ralph Hart - Irvine CA

Assignee:

Unisys Corporation - Blue Bell PA

International Classification:

G06F 1730

US Classification:

707201, 714 2, 709248

Abstract:

A method for sensing and regulating the level of synchronization between a file of audit blocks generated in a primary host for transfer to a secondary host. The audit files in a primary host are divided into audit blocks which are each identified with an audit block serial number. The individual audit blocks are transmitted through a network from a primary host to a secondary host wherein a tracker mechanism monitors the difference between the number of received audit blocks and the number of generated audit blocks residing at the primary host waiting to be transferred. When the disparity between the audit blocks received and the generated audit blocks waiting to be transmitted reaches a certain critical level, the tracker mechanism will initiate an advance speed up program to expedite the transfer in order to bring the primary and secondary audit files into greater synchronism. Further, the acknowledgment level can be set to indicate the number of audit blocks received in the secondary host for information back to the primary host and the acknowledgment level can be utilized in order to preset a critical value which will indicate that the speed up transfer operation should be initiated.

US Patent:

6877016, Apr 5, 2005

Filed:

Sep 13, 2001

Appl. No.:

09/951996

Inventors:

Donald Ralph Hart - Irvine CA, US
Kung Yi Lin - Irvine CA, US

Assignee:

Unisys Corporation - Blue Bell PA

International Classification:

G06F012/00
G06F017/30

US Classification:

707201, 707204

Abstract:

An on-line primary database is momentarily QUIESCED to enable a physically consistent snapshot of the primary database to be mirrored to a secondary database as a backup while allowing the primary database to continue on servicing multiple user applications.

US Patent:

6957221, Oct 18, 2005

Filed:

Sep 5, 2002

Appl. No.:

10/235763

Inventors:

Donald Ralph Hart - Irvine CA, US

Assignee:

Unisys Corporation - Blue Bell PA

International Classification:

G06F017/30

US Classification:

707100, 707101, 7071041, 711162

Abstract:

An online primary database is automatically configured to enable a physically consistent snapshot of the primary database at the secondary database to be uniquely mirrored to a secondary remote database as backup while allowing the specialized control audit images to be created at the primary database.

US Patent:

6983295, Jan 3, 2006

Filed:

Oct 24, 2002

Appl. No.:

10/280717

Inventors:

Donald Ralph Hart - Irvine CA, US

Assignee:

Unisys Corporation - Blue Bell PA

International Classification:

G06F 17/30
G06F 12/00

US Classification:

707204, 707200

Abstract:

A rapid database recovery program uses an auxiliary database means (D) mirrored to replicate a primary active database means (D). A utility and recovery program utilizes the primary audit file (A) to update the auxiliary database (D) to make it immediately available for transaction operations.

US Patent:

7200626, Apr 3, 2007

Filed:

Jan 22, 2004

Appl. No.:

10/762723

Inventors:

Courtney Chi Hoang - Fountain Valley CA, US
Patricia Jean Keller - Westminster CA, US
Alma Navarro de Jesus - Monrovia CA, US
Donald Ralph Hart - Mission Viejo CA, US

Assignee:

Unisys Corporation - Blue Bell PA

International Classification:

G06F 17/30

US Classification:

707204, 707200, 707100, 707201

Abstract:

A method is provided to verify a database copy of a primary database which has been replicated. A secondary physically consistent copy of the primary database is put in a state of quiesce while the primary database is allowed to resume update activity. The consistent copy, in a state of quiesce, can be used for database maintenance activities or as a recovery source should the primary database be damaged, but the consistent copy is first checked for integrity by using a Verify option before such recovery source is utilized.

US Patent:

7263537, Aug 28, 2007

Filed:

Aug 26, 2004

Appl. No.:

10/927384

Inventors:

Kung Yi Lin - Irvine CA, US
Shirley Jean Ritsch - Lake Forest CA, US
Donald Ralph Hart - Mission Viejo CA, US

Assignee:

Unisys Corporation - Blue Bell PA

International Classification:

G06F 17/30

US Classification:

707204

Abstract:

A method for creating multiple QUIESCE DATABASE Copies (QDC) on a single server by mirroring a disk copy of a live database that is in a quiesced state and splitting them from their source, and then bringing the mirrored disks containing online snapshots back online to the server.