Patent ID: 8225132
Filing Date: 2012-07-17
Classification: G06F,H04L

Abstract:
1. A storage system, comprising: a controller; a plurality of physical storage devices; a first switching device including a first loop which is connected to said controller; and a second switching device including a second loop which is connected to said controller; and wherein: in response to a signal supplied from said controller, said first switching device connects a physical storage device to said first loop, or disconnects that physical storage device from said first loop; in response to a signal supplied from said controller, said second switching device connects a physical storage device to said second loop, or disconnects that physical storage device from said second loop; each physical storage device is endowed with a function of acquiring an address, and is either an additional storage device, which is a physical storage device which is additionally provided, or an existing storage device, which is some physical storage device other than said additional storage devices; said controller executes first diagnostics processing consisting of: (1-1) disconnecting all of the existing storage devices from said first loop; (1-2) connecting an additional storage device to said first loop; (1-3) acquiring, via said first loop from the additional storage device which was connected to said first loop by said (1-2), an address which is acquired by the additional storage device; and (1-4) performing a first suitability decision, which is a decision as to the suitability or unsuitability of said address which was acquired in (1-3) above; if the result of said first suitability decision is negative, blocks the additional storage device which acquired the address acquired in (1-3) above; and said controller: if the result of said first suitability decision in said first diagnostics processing is affirmative, and if there is an additional storage device which is not yet connected for which said (1-2) has not been performed in said first diagnostics processing, performs said (1-2) for this not yet connected physical storage device; if the result of said first decision is affirmative for all of said additional storage devices, executes second diagnostic processing consisting of: (2-1) disconnecting all of the existing storage devices from said second loop; (2-2) connecting an additional storage device to said second loop; (2-3) acquiring, via said second loop from the additional storage device which was connected to said second loop by said (2-2), an address which is acquired by the additional storage device; and (2-4) performing a second suitability decision, which is a decision as to the suitability or unsuitability of said address which was acquired in said (2-3); if the result of said second suitability decision is negative, blocks the additional storage device which acquired an address in said (2-3), while on the other hand, if the result of said second suitability decision is affirmative, if there is an additional storage device which is not yet connected for which said (2-2) has not been performed in said second diagnostics processing, performs said (2-2) for this not yet connected physical storage device; if there is some additional storage device for which either said first diagnostics processing or said second diagnostics processing has not yet been performed, performs, for that additional storage device, that one of said first diagnostics processing and said second diagnostics processing which has not yet been performed; and if there is no additional storage device for which said first diagnostics processing and said second diagnostics processing have not yet been performed, and if moreover there is no additional storage device for which the result of either said first suitability decision or said second suitability decision is negative, connects all said physical storage devices both to said first loop and to said second loop, and moreover terminates said processing for additional provision by managing all of said additional storage devices as existing storage devices.