Patent ID: 7127557
Filing Date: 2006-10-24
Classification: G06F

Abstract:
1. A RAID apparatus for separating data according to a RAID configuration definition and reading/writing the data from/to a plurality of physical disk devices in parallel, comprising: a control unit for accessing said plurality of physical disk devices according to RLU (RAID logical unit) mapping based on said RAID configuration definition upon an I/O request from a host device; a table for storing old RAID configuration definition information which defines at least an old RAID level and a number of old logical devices, and new RAID configuration definition information which defines at least a new RAID level and a number of new logical devices; and a cache memory for temporarily storing data for changing the old RAID configuration to the new RAID configuration, wherein said control unit reads out the data from said plurality of physical disk devices to said cache memory according to the RAID logical unit mapping based on said old RAID configuration definition of said table, and writes the data which was read out to said cache memory to said plurality of physical disk devices according to the RAID logical unit mapping based on said new RAID configuration definition of said table in an active status.