SINGLE INDEX TO QUERY MULTIPLE BACKUP FORMATS

• US 20140258236A1
• Filed: 03/11/2013
• Published: 09/11/2014
• Est. Priority Date: 03/11/2013
• Status: Active Grant

• Current Assignee: CommVault Systems Incorporated
• Original Assignee: CommVault Systems Incorporated
• Inventors: Vijayan, Manoj Kumar
• Granted Patent: US 9,459,968 B2
• Time in Patent Office: Days
• US Class Current: 707/639
• CPC Class Codes: G06F 11/1448 Management of the data involved in backup or backup restore
• CPC Class Codes: G06F 11/1456 Hardware arrangements for backup
• CPC Class Codes: G06F 11/1458 Management of the backup or restore process
• CPC Class Codes: G06F 16/113 Details of archiving lifecycle management in storage systems G06F3/0649; backup systems G06F11/1446
• CPC Class Codes: G06F 16/116 Details of conversion of file system types or formats
• CPC Class Codes: G06F 16/14 Details of searching files based on file metadata
• CPC Class Codes: G06F 16/148 File search processing
• CPC Class Codes: G06F 2201/84 Using snapshots, i.e. a logical point-in-time copy of the data

Abstract

The disclosed techniques include generation of a single index table when backing up data in a first backup format to a backup storage system that uses a second backup format. Using the single index table, a query for a data item can be answered by searching the single index table. The single index table avoids having to search through multiple index tables, each corresponding to a different backup format that may be used for backing up the searched data item.

Claims

1. A computer program product comprising a computer-readable storage medium having code stored thereon, the code, when executed by a processor, causing the processor to implement a data copy method, the method comprising:

performing a first copy operation to generate first copy data in a first backup format, without generating a corresponding index for browsing the first copy data in the first copy format;

performing a second copy operation on the first copy data in the first copy format to generate second copy data in a second copy format; and

generating an index table comprising entries for one or more data items from the first copy data stored in the second copy data in the second copy format,

wherein each entry includes—

first access information for a data item to allow access to the data item in the second copy data, and

second access information to allow access to the data item in the first copy data, thereby allowing direct access to the data item based on information from the index table.

2. The computer program product of claim 1, wherein the performing the first copy operation comprises:

instructing a snapshot module to create a snapshot to generate the first copy data.

3. The computer program product of claim 1, wherein the first copy operation comprises creating a snapshot and the second copy operation comprises copying the snapshot to a secondary copy device.

4. The computer program product of claim 1, wherein the one or more data items comprise a data file, and the first access information comprises physical offset information and logical offset information.

5. The computer program product recited in claim 1, wherein the first access information comprises an archive file identification from a set of pre-determined archive file identification values indicating that a corresponding archive file is storing data in the first backup format.

6. A method of enabling browsing of data items stored in a backup or archive storage system in multiple formats including a first format, the method comprising:

receiving, at a computer, a search query from a user for a data item stored in the storage system;

querying an index table for an entry corresponding to the data item, wherein the index table includes information regarding data stored in multiple, different formats;

determining, based on the entry, that the selected data item corresponds to backup or archive data of a second format;

performing, by the computer, a restoration operation to restore the data item from the first format to a third format to permit presentation of at least some of the selected data to the user.

7. The method of claim 6, wherein the entry in the index table includes an archive file identification number that is pre-associated with the second format, wherein the second format is an archive format not usable by a user computer without prior processing, wherein the prior processing includes at least one of:

decryptions, decompression or conversion from a deduplicated format.

8. The method of claim 6, wherein the storage system includes a tape drive or a disk array and wherein the second format comprises a snapshot format.

9. The method of claim 6, wherein performing the restoration operation includes a first data staging operation in which data from the first format is staged into the second format and stored at the computer and a second staging operation in which data in the second format is staged to the format for presentation to the user, and wherein the staging of the second format to the format for presentation comprises generation of a directory tree for the data item

10. The method of claim 6, wherein performing the restoration operation includes a first data staging operation in which data from the first format is staged into the second format and stored at the computer and a second staging operation in which data in the second format is staged to the format for presentation to the user.

11. A computer-implemented data copy operation, comprising:

generating a snapshot of data on a client device,

wherein the snapshot is generating without generating a corresponding snapshot index for the data;

moving the snapshot to a tape drive,

wherein moving the snapshot includes copying of the data for which the snapshot was generated but without copying the corresponding snapshot index for the data;

generating a tape index for the snapshot data,

wherein the tape index includes a master index table comprising information regarding identities and logical offsets to data files included in the snapshot; and

,

causing a media agent to store the tape index and additional information related to restoration of the snapshot.

12. The method of claim 11, wherein the master index table includes version information for data files, tape offset values for data files and a list of users authorized to access data files.

13. The method of claim 11 wherein the master index table further includes information indicating that the data files are included in a snapshot, and wherein the master index table further includes information about whether the data files can be fully recovered by themselves.

14. The method of claim 11 wherein the master index table further includes information indicating that the data files are included in a snapshot.

15. The method of claim 11, further comprising:

assigning an archive ID to the tape index, the archive ID being from a subset of all possible values, wherein the subset of all possible values indicates that the tape index includes snapshotted data files.

16. A data copy apparatus, comprising:

means for generating a snapshot of data on a client device, wherein the snapshot is generating without generating a corresponding snapshot index for the data;

means for moving the snapshot to a tape drive, wherein the moving the snapshot includes copying of the data for which snapshot was generated but without copying the corresponding snapshot index for the data;

means for generating a tape index for the snapshot data, the tape index including a master index table comprising information regarding identities and logical offsets to data files included in the snapshot;

means for causing a media agent to store the tape index and additional information related to restoration of the snapshot.

17. The apparatus of claim 31, wherein the master index table includes version information for data files, tape offset values for data files and a list of users authorized to access data files.

18. The apparatus of claim 31 wherein the master index table further includes information indicating that the data files are included in a snapshot.

19. The apparatus of claim 33, wherein the master index table further includes information about whether the data files can be fully recovered by themselves.

20. The apparatus of claim 31, further comprising:

means for assigning an archive ID to the tape index, the archive ID being from a subset of all possible values, wherein the subset of all possible values indicates that the tape index includes snapshotted data files.