Patent ID: 7383395
Filing Date: 2008-06-03
Classification: G06F

Abstract:
1. A disk device, comprising: multiple disk controllers containing channel adapters, cache memories and disk adapters, a disk array containing a shared volume capable of being commonly accessed from the multiple disk controllers, and a switch for switching connections between the multiple disk controllers and the disk array, wherein the switch performs exclusive access control of the multiple disk controllers' writing on the shared volume, and performs control to match data other than modified data among the cache memories within the multiple disk controllers for keeping coherency, wherein when the switch receives a write access from one of the disk controllers to write on the shared volume, the switch temporarily stores write data in the memory inside the switch, and also sends the write data to other disk controllers not accessing the shared volume, and the disk controllers that received the write data, rewrite data other than modified data in the cache memory corresponding to the shared volume.