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:
Mar. 11, 1997
Filed:
Jul. 12, 1994
Tatsuo Matoba, Kawasaki-shi, JP;
Fujitsu Limited, , JP;
Abstract
Even if a plurality of disk units in a disk array which operate in parallel simultaneously causes faults, a system can instantaneously cope with a processing request without losing the data. For this purpose, a mirror disk unit in which two disk units are provided as one set is used as a component element of the disk array. The two disk units of the mirror disk unit are allocated to the disk unit for the present use and the disk unit for spare. Data is written into both the presently used disk unit and the spare disk unit. Data is read out from the present use disk unit. The occurrence of a fault of the disk unit is judged and the allocation is switched from the present use disk unit to the spare disk unit. In an idle state, a simulation to check the disk array is executed and fault information is collected. RAID3 or RAID5 in which a parity is stored in the mirror disk construction can be also used. Further, the present use disk unit is not constructed as a mirror disk and when the fault is judged in the present use disk unit, the data is copied to the spare disk unit, thereby dynamically realizing a mirror disk construction.