SYSTEMS AND METHODS TO PROCESS BLOCK-LEVEL BACKUP FOR SELECTIVE FILE RESTORATION FOR VIRTUAL MACHINES

• US 20140201152A1
• Filed: 12/06/2013
• Published: 07/17/2014
• Est. Priority Date: 01/11/2013
• Status: Active Grant

• Current Assignee: CommVault Systems Incorporated
• Original Assignee: CommVault Systems Incorporated
• Inventors: Kumarasamy, Paramasivam, Pawar, Rahul S., Mitkar, Amit, Kilaru, Satish Chandra
• Granted Patent: US 9,495,404 B2
• Time in Patent Office: Days
• US Class Current: 707/647
• CPC Class Codes: G06F 11/1458 Management of the backup or restore process
• CPC Class Codes: G06F 11/1461 Backup scheduling policy
• CPC Class Codes: G06F 11/1469 Backup restoration techniques
• CPC Class Codes: G06F 16/13 File access structures, e.g. distributed indices arrangements of input from, or output to, record carriers G06F3/06
• CPC Class Codes: G06F 16/168 Details of user interfaces specifically adapted to file systems, e.g. browsing and visualisation, 2d or 3d GUIs query results presentation G06F16/156
• CPC Class Codes: G06F 16/188 Virtual file systems
• CPC Class Codes: G06F 16/23 Updating
• CPC Class Codes: G06F 2009/45583 Memory management, e.g. access or allocation
• CPC Class Codes: G06F 2201/815 Virtual
• CPC Class Codes: G06F 2201/84 Using snapshots, i.e. a logical point-in-time copy of the data
• CPC Class Codes: G06F 9/45558 Hypervisor-specific management and integration aspects

Abstract

A data storage system protects virtual machines using block-level backup operations and restores the data at a file level. The system accesses the virtual machine file information from the file allocation table of the host system underlying the virtualization layer. A file index associates this virtual machine file information with the related protected blocks in a secondary storage device during the block-level backup. Using the file index, the system can identify the specific blocks in the secondary storage device associated with a selected restore file. As a result, file level granularity for restore operations is possible for virtual machine data protected by block-level backup operations without restoring more than the selected file blocks from the block-level backup data.

Claims

1. A method to process block-level data protection of virtual machine files for selective file-level restoration in a data management system, the method comprising:

automatically identifying with computer hardware an information store comprising virtual files associated with a virtual machine, wherein the virtual machine is associated with a media agent and a host operating system having a file allocation table (FAT) comprising file location information for each virtual file within the information store, wherein the media agent accesses the FAT during a block-level backup of the virtual machine;

automatically transferring with the computer hardware blocks of data comprising virtual files to be backed up from the information store to a secondary storage device to create transferred blocks of data in the secondary storage device;

automatically updating with the computer hardware a file index associating a location of each block of data in the information store with a location of a corresponding transferred block of data in the secondary storage device; and

automatically associating in the file index with the computer hardware the file location information for the virtual files to be backed up in each block of data with the location of the corresponding transferred block of data in the secondary storage device.

2. The method of claim 1 further comprising automatically retrieving with the computer hardware the file location information from the FAT by the media agent.

3. The method of claim 1 wherein the file location information comprises, for each virtual file, a linked list of one or more clusters across which the virtual file is stored on the information store.

4. The method of claim 1 wherein a storage manager instructs the media agent to attach to the host operating system underlying the virtual machine.

5. The method of claim 1 wherein a storage manager instructs the host operating system underlying the virtual machine to attach the media agent.

6. The method of claim 1 wherein a storage manager instructs the media agent to perform the block-level backup of the virtual machine and to create the file index by determining which blocks of data relate to which virtual files based at least in part on the file location information stored in the FAT of the host operating system.

7. The method of claim 1 wherein the media agent comprises a media agent index and the file index is associated with the media agent index.

8. The method of claim 1 wherein the media agent comprises a media agent index which incorporates the file index.

9. The method of claim 1 further comprising:

automatically querying with the computer hardware the media agent for an address of a virtual machine disk associated with the virtual machine, wherein the media agent looks up the address in a media agent index associated with the media agent; and

automatically receiving with the computer hardware the address in the information store of the virtual machine disk from the media agent.

10. The method of claim 1 further comprising creating with the computer hardware a second virtual machine comprising the media agent in virtual machine management software.

11. A system to process block-level data protection of virtual machine files for selective file-level restoration in a data management system, the system comprising:

computer hardware; and

computer-readable storage comprising computer-readable instructions that, when executed by the computer hardware, cause the computer hardware to perform operations defined by the computer-readable instructions, the computer-readable instructions configured to;

automatically identify an information store comprising virtual files associated with a virtual machine, wherein the virtual machine is associated with a media agent and a host operating system having a file allocation table (FAT) comprising file location information for each virtual file within the information store, wherein the media agent accesses the FAT during a block-level backup of the virtual machine;

automatically transfer blocks of data comprising virtual files to be backed up from the information store to a secondary storage device to create transferred blocks of data in the secondary storage device;

automatically update a file index associating a location of each block of data in the information store with a location of a corresponding transferred block of data in the secondary storage device; and

automatically associate in the file index the file location information for the virtual files to be backed up in each block of data with the location of the corresponding transferred block of data in the secondary storage device.

12. The system of claim 11 wherein the computer-readable instructions are further configured to automatically retrieve the file location information from the FAT.

13. The system of claim 11 wherein the file location information comprises, for each virtual file, a linked list of one or more clusters across which the virtual file is stored on the information store.

14. The system of claim 11 wherein a storage manager instructs the media agent to attach to the host operating system underlying the virtual machine.

15. The system of claim 11 wherein a storage manager instructs the host operating system underlying the virtual machine to attach the media agent.

16. The system of claim 11 wherein a storage manager instructs the media agent to perform the block-level backup of the virtual machine and to create the file index by determining which blocks of data relate to which virtual files based at least in part on the file location information stored in the FAT of the host operating system.

17. The system of claim 11 wherein the media agent comprises a media agent index and the file index is associated with the media agent index.

18. The system of claim 11 wherein the media agent comprises a media agent index which incorporates the file index.

19. The system of claim 11 wherein the computer-readable instructions are further configured to:

automatically query the media agent for an address of a virtual machine disk associated with the virtual machine, wherein the media agent looks up the address in a media agent index associated with the media agent; and

automatically receive the address in the information store of the virtual machine disk from the media agent.

20. The system of claim 11 wherein the computer-readable instructions are further configured to create a second virtual machine comprising the media agent in virtual machine management software.