Patent ID: 7281072

Claim:
A computer system comprising: a host entity for issuing IO requests; a redundant external storage virtualization controller (SVC) pair for performing IO operations in response to IO requests issued by the host entity comprising a first and a second external storage virtualization controller coupled to the host entity; and a set of at least one physical storage device for providing storage to the computer system, with at least one member of said set of at least one physical storage device comprising a PSD coupled to the said redundant storage virtualization controller pair through a point-to-point serial signal interconnect; wherein when one storage virtualization controller in the said redundant SVC pair is not on line or goes off line after being on line, the other storage virtualization controller in the said redundant SVC pair will automatically take over the functionality originally performed by the said one storage virtualization controller in the redundant SVC pair; and wherein in the redundant storage virtualization controller pair, each of the storage virtualization controllers further comprises: a central processing circuitry for performing the IO operations in response to IO requests of said host entity; at least one IO device interconnect controller coupled to said central processing circuitry; at least one host-side IO device interconnect port provided in a said at least one IO device interconnect controller for coupling to said host entity; and at least one device-side IO device interconnect port provided in a said at least one IO device interconnect controller coupled to said at least one physical storage device through said point-to-point serial-signal interconnect.