Storage system and operation method of storage system

Abstract

The present invention is able to improve the processing performance of a storage system by respectively virtualizing the external volumes and enabling the shared use of such external volumes by a plurality of available virtualization storage devices. By virtualizing and incorporating the external volume of an external storage device, a first virtualization storage device is able to provide the volume to a host as though it is an internal volume. When the load of the first virtualization storage device increases, a second virtualization storage device 2 is newly introduced, and connected to the storage system. When a transfer direction is issued from a management terminal, the external volume relating to the selected logical volume is transferred from the first virtualization storage device to the second virtualization storage device.

1 . (canceled) 
     
     
         2 . A storage system comprising:
 at least one physical storage devices providing a logical volume;   a first virtualization device coupled to a computer and being configured to provide a first logical volume with a first identification number to the computer, wherein the first logical volume includes a first virtual storage area mapped to all or a part of a storage area of the logical volume, and   a second virtualization device coupled to the computer and a first virtualization device,   wherein the second virtualization device is configured to, in response to a request from the host:   obtain information of the first logical volume sent from the first virtualization device, and   provide a second logical volume to the computer, wherein the second logical volume includes a second virtual storage area mapped to the all or the part of the storage area, which is also mapped to the first virtual storage area in the first logical volume, of the logical volume,   wherein the second logical volume is provided to the computer with the first identification number included in the information obtained from the first virtualization device, but a port number of the second logical volume provided to the computer is different from a port number of the first logical volume provided to the computer.   
     
     
         3 . A storage system according to  claim 2 , wherein the first logical volume and the second logical volume are volumes of access targets by the computer. 
     
     
         4 . A storage system according to  claim 2 , wherein each of the first and second identification numbers is a logical unit number for identifying volumes of access targets by the computer. 
     
     
         5 . A storage system according to  claim 2 ,
 wherein the computer includes a plurality of host bus adapters,   wherein the first virtualization device includes the first port,   wherein the second virtualization device includes the second port,   wherein the first path is identified by the combination of a first host bus adapter number of identifying at least one of the host bus adapters, the first port number, and the first identification number for identifying the first logical volume, and   wherein the second path is identified by the combination of a second host bus adapter number for identifying at least one of the host bus adapters, the second port number, and the first identification number for identifying the first logical volume.   
     
     
         6 . A storage system according to  claim 2 , wherein the computer is configured to switch the first path to the second path in case that a request to the first logical volume through the first path is not processed by the first virtualization device. 
     
     
         7 . A storage system according to  claim 2 ,
 wherein information regarding an owner right, which indicates authority to use the logical volume, can be transferred by the first virtualization device to the second virtualization device, while both the first path and the second path are defined.   
     
     
         8 . A storage system according to  claim 2 ,
 wherein the storage system further includes an external storage system coupled to the first virtualization device and the second virtualization system through a storage area network, and   wherein the logical volume is in the external storage device.   
     
     
         9 . A storage system according to  claim 2 ,
 wherein the first virtualization device holds first mapping information indicating mapping between the first logical volume and the all or the part of the storage area in the logical volume, and   wherein the second virtualization device holds second mapping information indicating mapping between the second logical volume and the all or the part of the storage area in the logical volume.   
     
     
         10 . In a storage system comprising at least one physical storage devices providing a logical volume; a first virtualization device coupled to a computer and being configured to provide a first logical volume with a first identification number to the computer, wherein the first logical volume includes a first virtual storage area mapped to all or a part of a storage area of the logical volume, and a second virtualization device coupled to the computer and a first virtualization device,
 wherein the second virtualization device is configured to perform a method, in response to a request from the host, the method comprising:   obtaining information of the first logical volume sent from the first virtualization device,   providing a second logical volume to the computer, wherein the second logical volume includes a second virtual storage area mapped to the all or the part of the storage area, which is also mapped to the first virtual storage area in the first logical volume, of the logical volume, and   providing the second logical volume to the computer with the first identification number included in the information obtained from the first virtualization device, but a port number of the second logical volume provided to the computer is different from a port number of the first logical volume provided to the computer.   
     
     
         11 . A method according to  claim 10 , wherein the first logical volume and the second logical volume are volumes of access targets by the computer. 
     
     
         12 . A method according to  claim 10 , wherein each of the first and second identification numbers is a logical unit number for identifying volumes of access targets by the computer. 
     
     
         13 . A method according to  claim 10 ,
 wherein the computer includes a plurality of host bus adapters,   wherein the first virtualization device includes the first port,   wherein the second virtualization device includes the second port,   wherein the first path is identified by the combination of a first host bus adapter number of identifying at least one of the host bus adapters, the first port number, and the first identification number for identifying the first logical volume, and   wherein the second path is identified by the combination of a second host bus adapter number for identifying at least one of the host bus adapters, the second port number, and the first identification number for identifying the first logical volume.   
     
     
         14 . A method according to  claim 10 , wherein the computer is configured to switch the first path to the second path in case that a request to the first logical volume through the first path is not processed by the first virtualization device. 
     
     
         15 . A method according to  claim 10 ,
 wherein information regarding an owner right, which indicates authority to use the logical volume, can be transferred by the first virtualization device to the second virtualization device, while both the first path and the second path are defined.   
     
     
         16 . A method according to  claim 10 ,
 wherein the storage system further includes an external storage system coupled to the first virtualization device and the second virtualization system through a storage area network, and   wherein the logical volume is in the external storage device.   
     
     
         17 . A method according to  claim 10 ,
 wherein the first virtualization device holds first mapping information indicating mapping between the first logical volume and the all or the part of the storage area in the logical volume, and   wherein the second virtualization device holds second mapping information indicating mapping between the second logical volume and the all or the part of the storage area in the logical volume.