Controlling data consistency guarantees in storage apparatus

• US 20060015507A1
• Filed: 07/14/2005
• Published: 01/19/2006
• Est. Priority Date: 07/17/2004
• Status: Active Grant

• Current Assignee: International Business Machines Corporation
• Original Assignee: International Business Machines Corporation
• Inventors: Fuente, Carlos F., Butterworth, Henry E.
• Granted Patent: US 8,341,458 B2
• Time in Patent Office: Days
• US Class Current: 1/1
• CPC Class Codes: G06F 11/2064 while ensuring consistency
• CPC Class Codes: G06F 11/2071 using a plurality of controllers
• CPC Class Codes: G06F 2201/82 Solving problems relating to consistency ensuring consistency in mirrored systems G06F11/2064
• CPC Class Codes: G06F 2201/835 Timestamp

Abstract

An apparatus, method and computer program operable in a network controls consistency guarantees of a plurality of data copies in a storage apparatus, and includes: a lease control component for extending a lease to the storage apparatus; and a consistency freeze/thaw component responsive to a failure indication for initiating a consistency freeze action at the storage apparatus prior to expiration of the current group lease period. It may further include a timer component for waiting the apparatus for a predetermined period after the consistency freeze action, where the consistency freeze/thaw component is operable to initiate a thaw action at the storage apparatus.

Claims

1. An apparatus operable in a network for controlling consistency guarantees of a plurality of data copies in a storage apparatus, comprising:

a lease control component for extending a lease to the storage apparatus; and

,

a consistency freeze/thaw component responsive to a failure indication for initiating a consistency freeze action at the storage apparatus prior to expiration of a current group lease period.

2. The apparatus of claim 1, further comprising:

a timer component for waiting for a predetermined period after the consistency freeze action,

wherein the consistency freeze/thaw component is operable to initiate a thaw action at the storage apparatus.

3. The apparatus of claim 1, wherein the lease control component operates lease heartbeat communications in the network.

4. The apparatus of claim 1, wherein the lease control component and another lease control component cooperate to maintain operation in response to a single failure and to signal failure to the consistency freeze component in response to a multiple failure.

5. The apparatus of claim 1, wherein the lease component comprises a group lease component.

6. The apparatus of claim 1, wherein the network is a storage area network.

7. The apparatus of claim 1, wherein the lease control component is located in the storage apparatus.

8. A storage area network comprising:

a storage apparatus;

a lease control component for extending a lease to the storage apparatus; and

,

a consistency freeze/thaw component responsive to a failure indication for initiating a consistency freeze action at the storage apparatus prior to expiration of a current group lease period.

9. The storage area network of claim 8, further comprising:

a timer component for waiting for a predetermined period after the consistency freeze action,

wherein the consistency freeze/thaw component is operable to initiate a thaw action at the storage apparatus.

10. The storage area network of claim 8, further comprising another lease control component, the lease control component and the other lease control component to cooperate to maintain operation in response to a single failure and to signal failure to the consistency freeze component in response to a multiple failure.

11. A method of operating an apparatus in a network for controlling consistency guarantees of a plurality of data copies in a storage apparatus, comprising:

extending, by a lease control component, a lease to the storage apparatus; and

in response to a failure indication, initiating, by a consistency freeze/thaw component, a consistency freeze action at the storage apparatus prior to expiration of a current group lease period.

12. The method of claim 11, further comprising:

waiting the apparatus, by a timer component, for a predetermined period after the consistency freeze action; and

,

initiating, by the consistency freeze/thaw component, a thaw action at the storage apparatus.

13. The method of claim 11, wherein the lease control component operates lease heartbeat communications in the network.

14. The method of claim 11, wherein the lease control component and another lease control component cooperate to maintain operation in response to a single failure and to signal failure to the consistency freeze component in response to a multiple failure.

15. The method of claim 11, wherein the lease component comprises a group lease component.

16. The method of claim 11, wherein the network is a storage area network.

17. The method of claim 11, wherein the lease control component is located in the storage apparatus.

18. An article of manufacture comprising:

a computer-readable medium; and

,

means in the medium for extending a lease to a storage apparatus, and in response to a failure indication, initiating a consistency freeze action at the storage apparatus prior to expiration of a current group lease period.

19. The article of claim 18, wherein the means is further for waiting for a predetermined period after the consistency freeze action.

20. The article of claim 19, wherein the means is further for initiating a thaw action at the storage apparatus.