Patent ID: 8195902
Filing Date: 2012-06-05
Classification: G06F

Abstract:
1. A storage system, comprising: a plurality of host computers; at least one storage subsystem; and a management computer, wherein each storage subsystem includes volumes storing data requested by the host computers to be written, the volumes including primary volumes from which data is copied, and secondary volumes to which data is copied, wherein the primary volumes and the secondary volumes form copy pairs, wherein the management computer is configured to: (A) obtain a plurality of copy pair definition information from each of the plurality of host computers, the plurality of copy pair definition information indicating associations between the primary volumes and the secondary volumes, and hold the plurality of copy pair definition information among a plurality of copy group definition tables in the management computer; and; (B) remove at least one duplicate copy pair definition information from the plurality of copy pair definition information obtained from the plurality of host computers by executing to: (B1) pick up a certain copy pair definition information from one of the copy group definition tables from the plurality of copy pair definition information obtained from the plurality of host computers, and register the certain copy pair definition information in a count table, (B2) repeat picking up the certain copy pair definition information from each of the copy group definition tables from the plurality of copy pair definition information obtained from the plurality of host computers to register in the count table how many times the certain copy pair definition information is stored in the plurality of copy group definition tables; (B3) repeat steps (B1) and (B2) for a next copy pair definition information from each of the copy group definition tables until each piece of copy pair definition information stored in the plurality of copy group definition tables has been registered in the count table; and (B4) remove any copy group definition table which is determined from the count table to be unnecessary because the copy pair definition information contained therein duplicates copy pair definition information stored in the other ones of the copy group definition table; and (C) collect copy pair statuses of the copy pairs from the at least one storage subsystem via each of the host computers, based on the copy pair definition information registered in the remaining copy group definition table or tables, to avoid obtaining copy pair status of the same copy pair more than once.