Patent ID: 9239680
Filing Date: 2016-01-19
CPC Classification: G06F

Claim Text:
1. A first storage system coupled to a computer and a second storage system, the first storage system comprising: a controller; a first virtual volume provided to the computer, the first virtual volume being mapped with a first external volume in the second storage system; a second virtual volume provided to the computer; and a storage pool associated with a second external volume in the second storage system, wherein, upon receiving a first write request to the first virtual volume, the controller forwards the first write request to the first external volume, wherein, upon receiving a second write request to the second virtual volume, the controller allocates, to the second virtual volume, at least one storage area of the storage pool associated with the second external volume, wherein, upon receiving a request to allocate another second external volume to the storage pool, the controller acquires a device status of another second external volume, and rejects the request to allocate the another second external volume to the storage pool on the basis of the device status of the another second external volume, if the device status of the another second external volume is blocked or being formatted, the controller determines whether the another second external volume is available by determining whether the another second external volume is already in use, the another second external volume being determined to be in use if a path has already been defined for the another second external volume, a storage function is using the another second external volume or the another second external volume has been reserved to store a copy of data, wherein, if the another second external volume is determined to be in use, the controller allocates the another second external volume to the storage pool when available, and rejects the request to allocate the another second external volume when unavailable, and wherein the storage function is a copy function.