Patent ID: 6757792
Filing Date: 2004-06-29
Classification: G06F

Abstract:
A storage system (allowing a host computer to make accesses to disc storages and) comprising one or more storage controllers and storages, and allowing a host computer to make accesses to said storages without suspending the operation of the storage system even while the configuration of the storage system is being changed by adding or removing a storage controller from the said storage system, wherein:each of said storage controllers includes: a channel interface connected to said host computer; an interface connected to said storages; and a management-information memory for storing management information of said storage system; wherein if said storage system includes a plurality of said storage controllers, then said management-information memories employed in said storage controllers are connected to each other by a management-information-memory switch having a switch-internal management-information memory module; if said storage system includes only one said storage controller, then said management-information memory of said storage controller has a controller-internal management-information memory controller and a controller-internal management-information memory module; if said storage system includes a plurality of said storage controllers, then said management-information memories employed in said storage controllers each have said controller-internal management-information memory controller; if said storage system includes only one said storage controller, then said controller-internal management-information memory controller makes an access to said controller-internal management-information memory module inside said storage controller; and if said storage system includes a plurality of said storage controllers, then said controller-internal management-information memory controllers make accesses to said switch-internal management-information memory module inside said management-information-memory switch.