Configuration management apparatus and method

A configuration defining method in a computer system including a host computer and a storage device having disk drives configured as at least one data volume for storing data and a cache area which temporarily holds data, and a virtualization device for providing a virtual volume to the host computer, the virtual volume related to the data volume, comprising:

• setting, in said virtualization device, an amount of resource corresponding to an amount of cache area that is assigned to the data volume from the storage device, said setting including:
• obtaining assignment information which indicates the amount of the cache area that has been assigned to the data volume from the storage device,
• obtaining a relationship between the data volume and the virtual volume from the virtualization device,
• determining whether or not a resource, related to the virtual volume, for holding data for the virtual volume can be assigned to the virtual volume in the virtualization device or not based on the amount of the cache area that has been assigned to the data volume related to the virtual volume, and
• if the resource, related to the virtual volume, can be assigned to the virtual volume, then defining an amount of the resource, related to the virtual volume, to be assigned to the virtual volume.

A virtualization device for use in a computer system including a host computer, a storage device having disk drives configured to have at least one data volume for storing data and a cache area for temporarily holding the data, said virtualization device for providing a virtual volume to the host computer, the virtual volume related to the data volume, and a network interconnecting the host computer, storage device and virtualization device to each other, said virtualization device comprising:

• a network interface to be coupled to the network;
• and
• a processor coupled to the network interface,
• wherein the processor conducts setting, in said virtualization device, an amount of resource corresponding to an amount of cache area that has been assigned to the data volume from the storage device, said setting including obtaining assignment information which indicates an amount of cache area that has been assigned to the data volume from the storage device via the network interface, obtaining a relationship between the data volume and the virtual volume via the network interface, determining whether a resource, related to the virtual volume, for holding data for the virtual volume can be assigned to the virtualization device or not based on the amount of cache area that has been assigned to the data volume related to the virtual volume, and if the resource can be assigned to the virtualization device, then defining an amount of the resource to be assigned to the virtual volume, and setting the defined information to the virtualization device.