Method and system for performing recovery in a storage system

Patent metadata

Field	Value
Publication number	US-8954789-B2
Application number	US-201313913054-A
Country	US
Kind code	B2
Filing date	Jun 7, 2013
Priority date	Feb 25, 2010
Publication date	Feb 10, 2015
Grant date	Feb 10, 2015

Abstract

Method and system for performing recovery for a replicated copy of a storage space presented as a logical object is provided. An attribute associated with the logical object for enabling the recovery is set and when the storage space is replicated the attribute is stored as metadata for the replicated copy of the storage space. Based on the attribute, a clone of the logical object is presented as a writable option to write to the first replicated copy. After the write operation where information is written to the clone, a second replicated copy with the clone information is created. The clone is deleted after the second copy is generated.

First claim

What is Claimed is:

1. A system, comprising:
a storage system managing a storage space; and
a processor executable module for setting a recovery indicator for selecting between a first clone type and a second clone type for a recovery operation performed for maintaining consistency between information stored at a read-only copy of a storage space and information stored at the storage space after the read-only copy is created;
wherein the recovery indicator is set as an attribute of a logical object representing the storage space; and
wherein the storage space and the recovery indicator are replicated by generating a first read-only copy of the storage space and based on the recovery indicator and a selected clone type, a clone of the logical object is created after the first read-only copy is generated for the recovery operation.

2. The system of claim 1 , wherein a second read-only copy of the storage space is generated for capturing information written to the clone of the logical object.

3. The system of claim 2 , wherein the clone of the logical object is deleted, after the second read-only copy is generated.

4. The system of claim 1 , wherein the logical object for representing the storage space is a logical unit number (LUN).

5. The system of claim 4 , wherein prior to generating the first read-only copy, the processor executable module that manages the replication operation sets a LUN attribute as the recovery indicator indicating that recovery is needed for the LUN.

6. The system of claim 5 , wherein the LUN attribute is stored with the first read-only copy.

7. The system of claim 6 , wherein the first clone type is a LUN clone that is an image of the LUN that is replicated in the first read-only copy.

8. The system of claim 7 , wherein the LUN clone is deleted after the second read-only copy is generated.

9. The system of claim 2 , wherein for generating the second read-only copy, if the LUN attribute for recovery is set, a LUN clone name is modified by using a same name as the LUN that is replicated in the first read-only copy and the LUN name is modified such that the modified LUN name is different from the modified LUN clone name.

10. The system of claim 9 , wherein after the second read-only copy is generated, the modified LUN name and the modified LUN clone name are reversed to their original names.

11. The system of claim 1 , wherein recovery is performed for a virtual environment comprising of a plurality of virtual machines having access to the storage space.

12. A system, comprising:
a storage system managing a storage space represented as a logical unit number (LUN); and
a processor executable module for generating a LUN attribute for selecting between a first clone type and a second clone type for a recovery operation;
wherein the LUN attribute is stored with a first read-only copy of the LUN; and the first clone type is used for the recovery operation, where the first clone type is a copy of the LUN that is created after the first read-only copy is generated and to which an application is allowed to write.

13. The system of claim 12 , wherein the first clone type is a LUN clone.

14. The system of claim 13 , wherein a second read-only copy is generated by capturing information stored at the LUN clone including information added after the first read-only copy is generated; and the LUN clone is deleted after generating the second read-only copy.

15. The system of claim 14 , wherein the second read-only copy is generated after a LUN clone name is modified by using a same name for the LUN and the LUN name is modified such that the modified LUN name is different from the modified LUN clone name.

16. The system of claim 15 , wherein the modified LUN name and the modified LUN clone name are reversed to their original names after the second read-only copy is generated.

17. The system of claim 12 , wherein recovery is performed for a virtual environment with a plurality of virtual machines executed by a computing system, where the plurality of virtual machines have access to the storage space.

18. A system, comprising:
a storage system presenting a storage space as a logical object; and
a processor executable module for storing a recovery indicator with a first replicated read-only copy of information stored at the storage space; where the recovery indicator is used for selecting between a first clone type and a second clone type for a recovery operation; based on the recovery indicator, a clone of the storage space is provided as a writable option to write data to the storage space, after the first replicated read-only copy is created; and after writing to the clone, an original name of the logical object is used for renaming the clone of the storage space.

19. The system of claim 18 , wherein a second replicated read-only copy is generated for capturing changes to the clone of the storage space after the first replicated read-only copy is created.

20. The system of claim 18 , wherein a computing system executes the processor executable module for interfacing with the storage system and detecting when recovery for the LUN is needed, based on the recovery indicator.

21. The system of claim 20 , wherein the clone is a LUN clone presented by the processor executable module as a writable option.

22. The system of claim 21 , wherein the LUN clone is deleted after generating the second replicated read-only copy.

Assignees

• Netapp Inc

Inventors

• Rangachari Muralidharan
• Barve Anagha
• Karinta Vineeth

Classifications

• G06F11/1662 Primary

  the resynchronized component or unit being a persistent storage device (re-synchronization of failed mirror storage G06F11/2082; rebuild or reconstruction of parity RAID storage G06F11/1008) · CPC title

• G06F11/2094

  Redundant storage or storage space (G06F11/2056 takes precedence) · CPC title

• G06F3/065 Primary

  Replication mechanisms · CPC title