Patent ID: 7039757
Filing Date: 2006-05-02
Classification: G06F

Abstract:
1. A cluster disk subsystem comprising: a plurality of disk array units arranged in a cluster structure, each disk array unit including a plurality of disk drives, a common storage, and a controller to read and write data from and to said disk drives, said controller including a storage to store data from a host computer and a control information storage to store information to control said disk array units by said controller; and a cluster connection network for coupling said plurality of disk array units in said cluster structure, wherein logical partitioning is established through said controller of each disk array unit and said cluster connection network, wherein said controller of each disk array unit executes, for a first mode, communication between said plurality of disk array units to occur when processing among some units of said plurality of disk array units be done by referring to contents of control information storages in others of said plurality of disk array units, wherein when said cluster connection network receives a request from said host computer to disconnect a first of said disk array units from a remainder of said disk array units, then for a second mode said controller of each disk array unit prohibits communication between said plurality of disk array units other than said first disk array unit such that at least part of said common storage of said first disk array unit which is used for maintenance is kept communicating when processing in said first disk array unit be done by referring to contents of said common storage in said first disk array unit.