STORAGE CONTROLLER, STORAGE SYSTEM, AND CONTROL METHOD

• US 20150234709A1
• Filed: 12/03/2014
• Published: 08/20/2015
• Est. Priority Date: 02/20/2014
• Status: Active Grant

• Current Assignee: Fujitsu Limited
• Original Assignee: Fujitsu Limited
• Inventors: Koarashi, Hiroshi
• Granted Patent: US 9,697,087 B2
• Time in Patent Office: Days
• US Class Current: 1/1
• CPC Class Codes: G06F 11/1088 Reconstruction on already foreseen single or plurality of spare disks
• CPC Class Codes: G06F 11/1092 Rebuilding, e.g. when physically replacing a failing disk
• CPC Class Codes: G06F 11/1451 by selection of backup contents
• CPC Class Codes: G06F 11/2056 by mirroring
• CPC Class Codes: G06F 11/2069 Management of state, configuration or failover
• CPC Class Codes: G06F 11/2082 Data synchronisation
• CPC Class Codes: G06F 11/2087 with a common controller
• CPC Class Codes: G06F 11/2094 Redundant storage or storage space G06F11/2056 takes precedence
• CPC Class Codes: G06F 2201/84 Using snapshots, i.e. a logical point-in-time copy of the data

Abstract

A storage controller includes a reconstruction unit that reconstructs data of a storage device to be restored among the plurality of storage devices by using data read from redundant storage devices other than the storage device to be restored among the plurality of storage devices, and stores the reconstructed data into a first backup storage device among the plurality of backup storage devices, and a copy unit that copies the data read from the redundant storage devices into second backup storage devices assigned to the redundant storage devices from among the plurality of backup storage devices during reconstruction by the reconstruction unit.

Claims

1. A storage controller communicably connected to a plurality of storage devices having a redundant configuration and a plurality of backup storage devices through a communication path, the storage controller comprising:

a reconstruction unit that;

reconstructs data of a storage device to be restored among the plurality of storage devices by using data read from redundant storage devices other than the storage device to be restored among the plurality of storage devices, and

stores the reconstructed data into a first backup storage device among the plurality of backup storage devices; and

a copy unit that;

copies the data read from the redundant storage devices into second backup storage devices assigned to the redundant storage devices from among the plurality of backup storage devices during reconstruction by the reconstruction unit.

2. The storage controller according to claim 1, further comprising:

an IO control unit that reads data from both the redundant storage devices and the second backup storage devices having data of the redundant storage devices stored therein, when receiving a read request from a host device.

3. The storage controller according to claim 2, wherein the IO control unit writes data into both the redundant storage devices and the second backup storage devices having data of the redundant storage devices stored therein, when receiving a write request from the host device.

4. The storage controller according to claim 1, further comprising:

an assigning unit that assigns the plurality of backup storage devices to the plurality of the storage devices, wherein the copy unit stores the data read from the redundant storage devices into the second backup storage devices assigned by the assigning unit.

5. The storage controller according to claim 4, wherein

when a number of the plurality of backup storage devices assignable to the plurality of storage devices is smaller than a number of the plurality of storage devices, the assigning unit assigns the plurality of backup storage devices preferentially to a storage device with low stability among the plurality of storage devices.

6. The storage controller according to claim 1, further comprising:

a redundant configuration change unit configured to change the redundant configuration by replacing a storage device with low stability among the plurality of storage devices with a backup storage device having a copy of the storage device with low stability, after the reconstruction by the reconstruction unit is completed.

7. A storage system comprising:

a plurality of storage devices having a redundant configuration;

a plurality of backup storage devices;

a reconstruction unit that;

reconstructs data of a storage device to be restored among the plurality of storage devices by using data read from redundant storage devices other than the storage device to be restored among the plurality of storage devices, and

stores the reconstructed data into a first backup storage device among the plurality of backup storage devices; and

a copy unit that;

copies the data read from the redundant storage devices into second backup storage devices assigned to the redundant storage devices from among the plurality of backup storage devices during reconstruction by the reconstruction unit.

8. The storage system according to claim 7, further comprising:

an IO control unit that reads data from both the redundant storage devices and the second backup storage devices having data of the redundant storage devices stored therein, when receiving a read request from a host device.

9. The storage system according to claim 7, wherein the IO control unit writes data into both the redundant storage devices and the second backup storage devices having data of the redundant storage devices stored therein, when receiving a write request from the host device.

10. The storage system according to claim 7, further comprising:

an assigning unit that assigns the plurality of backup storage devices to the plurality of the storage devices, wherein the copy unit stores the data read from the redundant storage devices into the second backup storage devices assigned by the assigning unit.

11. The storage controller according to claim 10, wherein

when a number of the plurality of backup storage devices assignable to the plurality of storage devices is smaller than a number of the plurality of storage devices, the assigning unit assigns the plurality of backup storage devices preferentially to a storage device with low stability among the plurality of storage devices.

12. The storage system according to claim 7, further comprising:

a redundant configuration change unit configured to change the redundant configuration by replacing a storage device with low stability among the plurality of storage devices with a backup storage device having a copy of the storage device with low stability, after the reconstruction by the reconstruction unit is completed.

13. A control method for a storage apparatus with a plurality of storage devices having a redundant configuration and a plurality of backup storage devices, the method comprising:

reconstructing, using a computer, data of a storage device to be restored among the plurality of storage devices by using data read from redundant storage devices other than the storage device to be restored among the plurality of storage devices, and

storing, using a computer, the reconstructed data into a first backup storage device among the plurality of backup storage devices; and

copying, using a computer, the data read from the redundant storage devices into second backup storage devices assigned to the redundant storage devices from among the plurality of backup storage devices during reconstruction by the reconstruction unit.