System and method for performing an image level snapshot and for restoring partial volume data

• US 9,208,160 B2
• Filed: 10/09/2014
• Issued: 12/08/2015
• Est. Priority Date: 11/13/2003
• Status: Active Grant

• Current Assignee: CommVault Systems Incorporated
• Original Assignee: CommVault Systems Incorporated
• Inventors: Prahlad, Anand, Ngo, David, Varadharajan, Prakash, Pawar, Rahul S., Kumar, Avinash
• Primary Examiner(s): Corrielus, Jean M
• Application Number:
  US14/511,055
• Publication Number:
  US 20150095285A1
• Time in Patent Office: 425 Days
• Field of Search: 707/610, 711/162, 711/136
• US Class Current: 1/1
• CPC Class Codes: G06F 11/1435 using file system or storage system metadata
• CPC Class Codes: G06F 11/1446 Point-in-time backing up or restoration of persistent data
• CPC Class Codes: G06F 11/1448 Management of the data involved in backup or backup restore
• CPC Class Codes: G06F 11/1469 Backup restoration techniques
• CPC Class Codes: G06F 16/128 Details of file system snapshots on the file-level, e.g. snapshot creation, administration, deletion use of snapshots for error detection or correction G06F11/14, G06F11/16
• CPC Class Codes: G06F 16/178 Techniques for file synchronisation in file systems
• CPC Class Codes: G06F 16/1844 Management specifically adapted to replicated file systems
• CPC Class Codes: G06F 16/22 Indexing; Data structures therefor; Storage structures
• CPC Class Codes: G06F 16/285 Clustering or classification
• CPC Class Codes: G06F 16/86 Mapping to a database
• CPC Class Codes: G06F 2201/80 Database-specific techniques
• CPC Class Codes: G06F 2201/805 Real-time
• CPC Class Codes: G06F 2201/84 Using snapshots, i.e. a logical point-in-time copy of the data
• CPC Class Codes: Y10S 707/99944 Object-oriented database structure
• CPC Class Codes: Y10S 707/99952 Coherency, e.g. same view to multiple users
• CPC Class Codes: Y10S 707/99953 Recoverability
• CPC Class Codes: Y10S 707/99955 Archiving or backup

Abstract

The present invention relates to a method for performing an image level copy of an information store. The present invention comprises performing a snapshot of an information store that indexes the contents of the information store, retrieving data associated with the contents of the information store from a file allocation table, copying the contents of the information store to a storage device based on the snapshot, and associating the retrieved data with the copied contents to provide file system information for the copied contents.

Claims

1. A method in a computing system of creating snapshots for an information store, the method comprising:

performing a first snapshot of one or more first blocks of data stored in an information store at a first time;

obtaining file information that maps the changed blocks of data in the first snapshot to one or more file names;

performing a second snapshot of the one or more second blocks or data stored in the information store at a second time, the second time occurring after the first time;

identifying changed blocks of data in the second snapshot that changed after the first time and before the second time;

obtaining file information that maps the changed blocks of data in the second snapshot to one or more files comprising one or more file names;

storing the second snapshot in association with the file information;

automatically obtain copies of the changed blocks of data from the information store, and store the copies in association with the second snapshot and the file information;

displaying in a user interface the one or more file names in the first snapshot at the first point in time, and the one or more file names in the second snapshot at the second point in time, by accessing the file information stored in association with the first and second snapshots; and

in response to a user request to restore at least one of the file names at the second point in time, using the file information stored in association with the second snapshot to restore the one or more first blocks stored in the first snapshot and the changed blocks stored in the second snapshot.

2. The method of claim 1 wherein the file information is obtained from a file access table.

3. The method of claim 1 wherein the second snapshot identifies where the copies of the changed blocks of data are stored.

4. The method of claim 1 wherein storing of the second snapshot automatically identifies one or more previously saved snapshots where previous copies of the changed blocks were stored.

5. The method of claim 1 wherein the file information includes one or more file names associated with one or more of the changed blocks of data.

6. The method of claim 1 further comprising storing copies of each of the one or more files in association with a previous snapshot.

7. The method of claim 1 further comprising identifying a plurality of snapshots stored in association with a copy of a first cluster or file.

8. The method of claim 1 wherein identifying the changed blocks uses a block filter to identify changes.

9. The method of claim 1 further comprising identifying a plurality of snapshots stored in association with a copy of a first cluster or file, and restoring the first cluster or file at least partially by reading each of the copies of the first cluster or file.

10. The method of claim 1 wherein the one or more blocks are stored in clusters.

11. A system configured to create snapshots for an information store, the system comprising:

at least one storage manager comprising computer hardware, the storage manager directs one or more computers to perform a first snapshot of one or more first blocks of data stored in an information store at a first time, the storage manager further obtains file information that maps the first blocks of data in the first snapshot to one or more file names;

the storage manager directs performance of a second snapshot of one or second more blocks of data stored in the information store at a second time, the second time occurring after the first time;

the storage manager directs identification of changed blocks of data in the second snapshot that changed after the first time and before the second time;

the storage manager directs obtaining file information that maps the changed blocks of data to the one or more files comprising one or more file names;

the storage manager directs storage of the second snapshot in association with the file information;

the storage manager directs automatically obtaining copies of the changed blocks of data from the information store, and store the copies in association with the second snapshot and the file information; and

a user interface that displays the one or more file names in the first snapshot at the first point in time, and the one or more file names in the second snapshot at the second point in time, by accessing the file information stored in association with the first and second snapshots; and

the storage manager in response to a user request to restore at least one of the file names at the second point in time, uses the file information stored in association with the second snapshot to restore the one or more first blocks stored in the first snapshot and the changed blocks stored in second snapshot.

12. The system of claim 11 wherein the file information is obtained from a file access table.

13. The system of claim 11 wherein the second snapshot identifies where the copies of the changed blocks are stored.

14. The system of claim 11 wherein during storage of the second snapshot, the storage manager directs automatic identification of one or more previously saved snapshots where previous copies of the changed blocks were stored.

15. The system of claim 11 wherein the file information includes one or more file names associated with one or more of the changed blocks.

16. The system of claim 11 wherein the storage manager directs storage of copies of each of the one or more files in association with a previous snapshot.

17. The system of claim 11 wherein the storage manager directs identification of a plurality of snapshots stored in association with a copy of a first cluster or file.

18. The system of claim 11 wherein identification of the changed blocks uses a block filter to identify changes to the blocks of data that occur after the first snapshot.

19. The system of claim 11 the storage manager directs identification of a plurality of snapshots stored in association with a copy of a first cluster or file, and restoring the first cluster or file at least partially by reading each of the copies of the first cluster or file.

20. The system of claim 11 wherein the one or more blocks are stored in clusters.