The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Sep. 24, 1991
Filed:
Nov. 19, 1990
Blaine H Berger, Longmont, CO (US);
Bret P Smith, Longmont, CO (US);
International Business Machines Corporation, Armonk, NY (US);
Abstract
A technique is described for managing data storage devices and the data stored on them. A pair of data storage devices are maintained as identical copies. The dual copy function is provided without changing any current system or application software on the host. A set of status information is maintained for each record on the data storage devices. This status information includes information which allows only the changed records to be copied to a secondary device of the dual copy. This technique also provides high availability of data storage devices by swapping a failing data storage device with a good data storage device without host intervention. A joint array structure is used for routing host requests for information to and from the correct data storage device and keeping status information concerning the data storage devices.