Stored data reverification management system and method

• US 7,613,748 B2
• Filed: 12/19/2005
• Issued: 11/03/2009
• Est. Priority Date: 11/13/2003
• Status: Active Grant

• Current Assignee: CommVault Systems Incorporated
• Original Assignee: CommVault Systems Incorporated
• Inventors: Gokhale, Parag, Brockway, Brian, Lu, Jun
• Primary Examiner(s): Vo; Tim T.
• Assistant Examiner(s): MENG, JAU SHYA
• Application Number:
  US11/313,226
• Publication Number:
  US 20060242489A1
• Time in Patent Office: 1,415 Days
• Field of Search: None
• US Class Current: 1/1
• CPC Class Codes: G06F 11/14 Error detection or correction of the data by redundancy in operation G06F11/16 takes precedence
• CPC Class Codes: G06F 11/1448 Management of the data involved in backup or backup restore
• CPC Class Codes: G06F 16/219 Managing data history or versioning querying versioned data G06F16/2474; querying temporal data G06F16/2477
• CPC Class Codes: G06F 7/00 Methods or arrangements for processing data by operating upon the order or content of the data handled logic circuits H03K19/00
• CPC Class Codes: G11C 2029/0409 Online test
• CPC Class Codes: Y10S 707/99955 Archiving or backup

Abstract

A system and method are provided for verifying data copies and reverifying the copies over the life span of media according to a verification policy. Characteristics of media and use of media are tracked to provide metrics which may be used to dynamically reevaluate and reassign verification policies to optimize media usage. Copies that fail verification operations may be repaired by repeating a storage operation for recent copies or by substituting a close temporal copy of the failed copy.

Claims

1. A method for reverifying data, the method comprising:

receiving an indication to perform a first storage operation;

identifying a plurality of files stored on a first media device that are associated with the first storage operation;

organizing the plurality of files with one or more computer processors into at least a first data package of first data with a header, wherein the header of the first data package comprises first metadata, the first metadata comprising at least a first archive file identifier and a first sequence number;

performing the first storage operation on the first data stored on the first media device by transferring the first data package to a second media device with lower performance than the first media device to generate second data wherein the second data comprises at least a second data package with a second header, wherein the second header comprises second metadata comprising at least a second archive file identifier and a second sequence number;

verifying that the second data is an accurate copy of the first data by comparing the first metadata of the first data with second metadata associated with the second data;

updating a verification table to indicate results of the verification of the second data;

accessing a verification policy indicating a first reverification time period associated with reverifying the second data stored on the second media device, the first reverification time period being based at least on a life expectancy of the second media device;

initiating at least one reverification operation of the second data according to the first reverification time period;

accessing a usage history of the second media device, wherein the usage history comprises at least a number of storage operations performed on the second media data and, when the number of storage operations exceed exceeds a threshold amount, establishing a second reverification time period for the second data stored on the second media device, the second reverification time period being more frequent than the first reverification time period; and

initiating at least one reverification operation of the second data according to the second reverification time period.

2. The method of claim 1, wherein the outcome of the reverification operation and at least one physical storage characteristic are tracked to generate a metric, wherein the metric is applied to evaluate the verification policy.

3. The method of claim 2, wherein the metric applied to evaluate the verification policy comprises predicting media use to perform a storage operation according to a storage policy.

4. The method of claim 1, wherein when the reverification operation outcome fails, further comprising:

identifying a third media device; and

evaluating the verification policy of the third media device.

5. The method of claim 4, wherein said evaluating the verification policy of the third media device comprises modifying a third reverification time period for third data stored on the third media device.

6. The method of claim 1, wherein the at least one physical characteristic of the second media device comprises at least one of a storage media type and an environmental condition of the second media device.

7. The method of claim 1, wherein the at least one physical characteristic of the second media device comprises at least one of an amount of data written to the second media device and an average amount of data per storage operation on the second media device.

8. The method of claim 1, wherein the first reverification time period is further based on a data type of the second data.

9. A method for repairing reverified data, the method comprising:

identifying a plurality of files stored on a first media device that are associated with a first storage operation;

organizing the plurality of the files with one or more computer processors into a data package of first data for transfer to a second media device, wherein the first data comprises at least the plurality of the files;

performing the first storage operation on the first data by transferring the first data to the second media device wherein storing the first data on the second media generates a data copy;

verifying whether the data copy on the second media device is an accurate copy of the first data;

determining a first reverification time period specified by a verification policy, the first reverification time period being based at least on an anticipated life span of the second media device;

initiating at least one reverification operation for the data copy on the second media device according to the first reverification time period;

determining a second reverification time period based on at least one of a usage of the second media device and a history of past verification failures of data stored on the second media device;

initiating at least one reverification operation for the data copy according to the earlier of the first reverification time period and the second reverification time period; and

when the data copy fails the reverification operation, repairing the data copy, wherein repairing the data copy comprises identifying a close temporal copy, and updating the data copy with the close temporal copy.

10. The method of claim 9 wherein the close temporal copy is identified by consulting an index.

11. The method of claim 9 wherein the close temporal copy is a copy of data that is the same application type as the data copy.

12. The method of claim 9 wherein the close temporal copy is a copy of data from a time period similar to the data copy.

13. The method of claim 9 wherein the close temporal copy is identified according to user preferences.

14. The method of claim 9, further comprising, following said failure of the reverification operation:

identifying at least one storage characteristic of the second media device;

identifying at least one other media device sharing the at least one storage characteristic; and

modifying a second reverification policy associated with data stored on the at least one other media device.

15. The method of claim 14, wherein the at least one storage characteristic comprises an amount of storage operation transactions associated with the particular media device.

16. The method of claim 14, wherein the at least one storage characteristic comprises information associated with the second media device and the at least one other media device.