STORAGE SYSTEM AND METHOD OF TAKING OVER LOGICAL UNIT IN STORAGE SYSTEM

• US 20110296130A1
• Filed: 04/04/2011
• Published: 12/01/2011
• Est. Priority Date: 03/21/2008
• Status: Active Grant

• Current Assignee: Tetsuya Abe, Tetsuya Shirogane
• Original Assignee: Tetsuya Abe, Tetsuya Shirogane
• Inventors: ABE, Tetsuya, Shirogane, Tetsuya
• Granted Patent: US 8,209,505 B2
• Time in Patent Office: Days
• US Class Current: 711/165
• CPC Class Codes: G06F 3/0607 by facilitating the process of upgrading existing storage systems, e.g. for improving compatibility between host and storage device
• CPC Class Codes: G06F 3/0631 by allocating resources to storage systems
• CPC Class Codes: G06F 3/0635 by changing the path, e.g. traffic rerouting, path reconfiguration
• CPC Class Codes: G06F 3/0647 Migration mechanisms
• CPC Class Codes: G06F 3/067 Distributed or networked storage systems, e.g. storage area networks [SAN], network attached storage [NAS]

Abstract

A storage apparatus includes a drive unit in which a logical unit is formed, and a controller unit for accessing the logical unit by controlling the drive unit according to an access request sent from a host apparatus. The storage apparatus issues a logical unit takeover request to the other storage apparatuses, allocates a logical unit of another storage apparatus that will accept the transfer of the logical volume to its own logical unit according to a takeover approval sent from other storage apparatuses in response to the takeover request, and thereafter migrates data of the own logical unit to a logical unit of another storage apparatus. Subsequently, the path is switched so that the access request from the host apparatus is given to one of the other storage apparatuses.

Claims

1-11. -11. (canceled)

12. A storage system comprising:

a drive unit in which at least one logical unit is formed; and

a controller unit configured to access the at least one logical unit by controlling the drive unit in accordance with an access request sent from a host apparatus,

wherein the controller unit includes;

a virtual volume request unit configured to issue a virtual volume request to effect a virtual volume as the at least one logical unit, to a plurality of other storage apparatuses other than the drive unit;

a data replication unit configured to replicate data in each of the plurality of other storage apparatuses that will provide a virtual volume portion of the virtual volume, according to a virtual volume approval sent each from the plurality of other storage apparatuses in response to the virtual volume request;

an external storage configuration unit configured to allocate the virtual volume as the at least one logical unit of the drive unit, where said virtual volume is compilation of virtual volume portions which were provided in the plurality of other storage apparatuses in response to the virtual volume request sent from the virtual volume request unit; and

a path request unit configured to issue an access request for the virtual volume to the drive unit allocated with the virtual volume, to have the drive unit route the access request to a target storage apparatus of the plurality of other storage apparatuses providing the virtual volume.

13. A method for providing a drive unit having at least one logical unit in a storage system, the method comprising:

issuing a virtual volume request to effect a virtual volume as the at least one logical unit, to a plurality of other storage apparatuses other than the drive unit;

replicating data in each of the plurality of other storage apparatuses that will provide a virtual volume portion of the virtual volume, according to a virtual volume approval sent each from the plurality of other storage apparatuses in response to the virtual volume request;

allocating the virtual volume as the at least one logical unit of the drive unit, where said virtual volume is compilation of virtual volume portions which were provided in the plurality of other storage apparatuses in response to the virtual volume request; and

issuing an access request for the virtual volume to the drive unit allocated with the virtual volume, to have the drive unit route the access request to a target storage apparatus of the plurality of other storage apparatuses providing the virtual volume.

14. A portal apparatus adapted for deployment within a storage system, the portal apparatus comprising:

a drive unit in which at least one logical unit is formed; and

a controller unit configured to access the at least one logical unit by controlling the drive unit in accordance with an access request sent from a host apparatus,

wherein the controller unit includes;

a virtual volume request unit configured to issue a virtual volume request to effect a virtual volume as the at least one logical unit, to a plurality of other storage apparatuses other than the drive unit;

a data replication unit configured to effect replication of data in each of the plurality of other storage apparatuses that will provide a virtual volume portion of the virtual volume, according to a virtual volume approval sent each from the plurality of other storage apparatuses in response to the virtual volume request;

an external storage configuration unit configured to allocate the virtual volume as the at least one logical unit of the drive unit, where said virtual volume is compilation of virtual volume portions which were provided in the plurality of other storage apparatuses in response to the virtual volume request sent from the virtual volume request unit; and

a path request unit configured to process an access request for the virtual volume, to route the access request to a target storage apparatus of the plurality of other storage apparatuses providing the virtual volume.