Storage system and operation method of storage system

A storage system comprising:

• an external storage device including a plurality of external physical storage devices and a controller which configures an external logical volume on said external physical storage devices and controls to access said external physical storage devices according to a RAID configuration;
• and
• a plurality of virtualization storage devices coupled to said external storage device, the virtualization storage devices including a first virtualization storage device which includes a plurality of first physical storage devices and provides a first logical volume configured on said first physical storage devices and a first virtual volume which is mapped to said external logical volume, and a second virtualization storage device which includes a plurality of second physical storage devices and provides a second logical volume configured on said second physical storage devices and a second virtual volume which is mapped to said external logical volume,
• wherein said first virtualization storage device defines a first path between a host computer and said first virtual volume mapped to said external logical volume in said external storage device and said second virtualization storage device defines a second path between said host computer and said second virtual volume mapped to said external logical volume in said external storage device,
• wherein information regarding an owner right, which indicates authority to use said external logical volume, can be transferred by said first virtualization storage device to said second virtualization storage device or by said second virtualization storage device to said first virtualization storage device, while both said first path and said second path are defined,
• wherein when said first virtualization storage device has said owner right and receives a first write command to said first virtual volume through said first path, said first virtualization storage device transfers said first write command to said external logical volume mapped to said first virtual volume,
• wherein upon transferring said owner right from said first virtualization storage device to said virtualization second storage device while both said first path and said second path are defined, said second virtualization storage device, in response to receiving a second write command to said second virtual volume through said second path, transfers said second write command to said external logical volume mapped to said second virtual volume, and
• wherein when said first virtualization storage device does not have said owner right and receives said first write command through said first path, said first virtualization storage device rejects processing of said first write command to switch said first path to said second path.

A storage system comprising:

• an external storage device including a plurality of external physical storage devices and a controller which configures an external logical volume on said external physical storage devices and controls to access said external physical storage devices according to a RAID configuration;
• and
• a plurality of virtualization storage devices coupled to said external storage device and including a first virtualization storage device which includes a plurality of first physical storage devices and provides a first logical volume configured on said first physical storage devices and a first virtual volume which is mapped to said external logical volume, and a second virtualization storage device which includes a plurality of second physical storage devices and provides a second logical volume configured on said second physical storage devices and second virtual volume which is mapped to said external logical volume,
• wherein said first virtualization storage device defines a first path between a host computer and said first virtual volume mapped to said external logical volume in said external storage device and said second virtualization storage device defines a second path between said host computer and said second virtual volume mapped to said external logical volume in said external storage device,
• wherein an owner right which indicates authority to use said external logical volume is set for a selected one of said first and second virtualization storage devices which have virtual volumes mapped to said external logical volume while both said first path and said second path are defined,
• wherein when said first virtualization storage device has said owner right and receives a first write command to said first virtual volume through said first path, said first virtualization storage device transfers a third write command corresponding to said first write command to said external logical volume,
• wherein when information regarding said owner right of said first virtualization storage device is transferred by the first virtualization storage device to said second virtualization storage device while both said first path and said second path are defined, said second virtualization storage device, in response to receiving a second write command to said second virtual volume through said second path, transfers a fourth write command corresponding to said second write command to said external logical volume, and
• wherein when said first virtualization storage device does not have said owner right and receives said first write command through said first path, said first virtualization storage device rejects processing of said first write command to switch said first path to said second path.

A method performed in a storage system coupled to a host computer and having an external storage device including a plurality of external physical storage devices and a controller which configures an external logical volume on said external physical storage devices and controls to access said external physical storage devices according to a RAID configuration, and a plurality of virtualization storage devices coupled to said external storage device, said virtualization storage devices including a first virtualization storage device which includes a plurality of first physical storage devices and provides a first logical volume configured on said first physical storage devices and a first virtual volume which is mapped to said external logical volume and a second virtualization storage device which includes a plurality of second physical storage devices and provides a second logical volume configured on said second physical storage devices and a second virtual volume which is mapped to said external logical volume, the method comprising the steps of:

• defining both a first path between said host computer and said first virtual volume mapped to said external logical volume in said external storage device and a second path between said host computer and said second virtual volume mapped to said external logical volume in said external storage device,
• determining a first load of said first virtualization storage device and a second load of said second virtualization storage device,
• providing an owner right, which indicates authority to use said external logical volume, to one of said first and second virtualization storage devices according to said first load of said first virtualization storage device and said second load of said second virtualization storage device,
• transferring information regarding said owner right by one of said first and second virtualization storage devices to another of said first and second virtualization storage devices while both said first path and said second path are defined based upon said determined first load and second load,
• wherein if said first virtualization storage device has said owner right and receives a first write command to said first virtual volume through said first path, said first virtualization storage device transfers a third write command corresponding to the first write command to said external logical volume,
• wherein if said first virtualization storage device does not have said owner right and receives said first write command through said first path, said first virtualization storage device rejects processing of said first write command to switch said first path to said second path,
• wherein if said second virtualization storage device has said owner right and receives a second write command to said second virtual volume through said second path, said second virtualization storage device transfers a fourth write command corresponding to the second write command to said external logical volume, and
• wherein if said second virtualization storage device does not have said owner right and receives said second write command through said second path, said second virtualization storage device rejects processing of said second write command to switch said second path to said first path.

A method performed in a storage system having an external storage device including a plurality of external physical storage devices and a controller which configures an external logical volume on said external physical storage devices and controls to access said external physical storage devices according to a RAID configuration, and a plurality of virtualization storage devices coupled to said external storage device, the virtualization storage devices including a first virtualization storage device which includes a plurality of first physical storage devices and provides a first logical volume configured on said first physical storage devices and a first virtual volume which is mapped to said external logical volume, and a second virtualization storage device which includes a plurality of second physical storage devices and provides a second logical volume configured on said second physical storage devices and a second virtual volume which is mapped to said external logical volume, the method comprising the steps of:

• defining both a first path between a host computer and said first virtual volume mapped to said external logical volume in said external storage device and a second path between said host computer and said second virtualization volume mapped to said external logical volume in said external storage device,
• determining a first load of said first virtualization storage device and a second load of said second virtualization storage device,
• transferring information regarding an owner right, which indicates authority to use said external logical volume, by one of said first and second virtualization storage devices to another of said first and second virtualization storage devices, while both said first path and said second path are defined, based upon said determined first load and second load,
• transferring by said first virtualization storage device, when said first virtualization storage device has said owner right which indicates authority to use said external logical volume and in response to receiving a first write command to said first virtual volume through said first path, a third write command to said external logical volume corresponding to said first virtual volume,
• rejecting, if said first virtualization storage device does not have said owner right and receives said first write command through said first path, processing of said first write command to switch said first path to said second path, and
• transferring by said second virtualization storage device, after said owner right is transferred to said second virtualization storage device from said first virtualization storage device while both said first path and said second path are defined and in response to receiving a second write command to said second virtual volume, a fourth write command to said external logical volume corresponding to said second virtual volume.

A method performed in a storage system having an external storage device including a plurality of external physical storage devices and a controller which configures an external logical volume on said external physical storage devices and controls to access said external physical storage devices according to a RAID configuration, a plurality of virtualization storage devices coupled to said external storage device and including a first virtualization storage device which includes a plurality of first physical storage devices and provides a first logical volume configured on said first physical storage devices and a second virtualization storage device which includes a plurality of second physical storage devices and provides a second logical volume configured on said second physical storage devices and, the method comprising the steps of:

• mapping a first virtual volume of said first virtualization storage device to said external logical volume,
• mapping a second virtual volume of said second virtualization storage device to said external logical volume,
• defining both a first path between a host computer and said first virtual volume mapped to said external logical volume in said external storage device and a second path between said host computer and said second virtual volume mapped to said external logical volume in said external storage device,
• transferring information regarding an owner right, which indicates authority to use said external logical volume, by one of said first and second virtualization storage devices to another of said first and second virtualization storage devices while both said first path and said second path are defined according to a first load of said first virtualization storage device and a second load of said second virtualization storage device,
• transferring by said first virtualization storage device, when said first virtualization storage device has said owner right and in response to receiving a first write command to said first virtual volume through said first path, a third write command to said external logical volume corresponding to said first virtual volume,
• rejecting, if said first virtualization storage device does not have said owner right and receives said first write command through said first path, processing of said first write command to switch said first path to said second path, and
• transferring by said second virtualization storage device, after said owner right is transferred to said second virtualization storage device from said first virtualization storage device while both said first path and said second path are defined and in response to receiving a second write command to said second virtualization volume through said second path, a fourth write command to said external logical volume corresponding to said second virtual volume.