Patent ID: 8489918

Claim:
A storage system, comprising: a disk device for providing a volume for storing data to a host system; a channel adapter for writing data from the host system to the disk device via a cache memory; a disk adapter for transferring data to and from the disk device; and a plurality of processor packages each including at least one processor for controlling the channel adapter and the disk adapter, wherein, as triggered by detection of a failure in any specified processor package of the plurality of processor packages, a first processor for the specified processor package is temporarily substituted with a second processor for another processor package based on load information which indicates a performance of each of the plurality of processor packages and based on a determination that an operation ratio of the second processor for the another processor package is below a predetermined threshold, as an assignment destination of ownership, which is assigned to the first processor for the specified processor package, for accessing a retained or added resource group, thereby making the transition to an ownership-substituted state, wherein, as triggered by an event that the failure is no longer detected in the specified processor package, the second processor for the another processor package cancels the ownership-substituted state, wherein the first processor assigns pieces of ownership to be substituted at the same time as preliminary ownership that is ownership to be handled in advance, from the first processor to the second processor, so that the first processor has the second processor control the channel adapter in accordance with a command received from the host system, wherein the second processor has the first processor continue controlling the channel adapter in accordance with a command already received from the host system until the preliminary ownership is assigned, and wherein, as triggered by the completion of the entire processing of the already received command, the first processor regulates the control of the channel adapter and assigns real ownership as actual ownership to the second processor.