Patent ID: 7558916
Filing Date: 2009-07-07
Classification: G06F,H04L

Abstract:
1. A storage system in which a plurality of storage apparatuses are connected to a network and configured into a plurality of storage groups, wherein each of the storage apparatuses has a processor, a memory, a channel interface and a disk interface, wherein each storage apparatus belongs to at least one of the storage groups, retains in the memory thereof configuration information of each of storage apparatuses in said at least one storage group, a priority number representing a priority of said each storage apparatus in each of said at least one storage group to become a substitute master when a failure occurs in a master storage apparatus in said each storage group, and management information of said at least one storage group, said configuration information and management information are common among all of said storage apparatuses configured in the same storage group, wherein a first storage apparatus with the highest priority number in said each storage group is configured as said master storage apparatus whose processor performs virtualization processing of storage apparatuses in said each storage group by presenting said storage apparatuses in said each storage group as a single virtual storage apparatus to a host system, presenting volumes configured in memories of said respective storage apparatuses in said each storage group as at least primary and secondary virtual volumes of the single virtual storage apparatus to the host system, receiving data I/O processing requests designating said virtual volumes sent from the host system, and performing data I/O processing for a received data I/O processing request from the host system to said virtual storage apparatus which involves a volume configured in the memory of said master storage apparatus for data reading and writing requested by the host system, wherein a second highest priority number is given to another one of the storage apparatuses in said storage group to become the substitute master when a failure occurs in the master storage apparatus, the priority numbers are either continuous or non-continuous integer numbers, and some of the priority numbers are shared by two or more of the storage apparatuses in said storage group, and wherein a storage apparatus with the lowest priority number in an on-line storage group which directly conducts data input and output with the host system is also configured as a master storage apparatus in an archive storage group used as an archive of the on-line storage group.