DATA RECOVERY OPERATIONS, SUCH AS RECOVERY FROM MODIFIED NETWORK DATA MANAGEMENT PROTOCOL DATA

• US 20120084523A1
• Filed: 09/23/2011
• Published: 04/05/2012
• Est. Priority Date: 09/30/2010
• Status: Active Grant

• Current Assignee: CommVault Systems Incorporated
• Original Assignee: CommVault Systems Incorporated
• Inventors: Littlefield, Duncan A., Nallathambi, Vimal K., Chanchlani, Girish
• Granted Patent: US 9,244,779 B2
• Time in Patent Office: Days
• US Class Current: 711/162
• CPC Class Codes: G06F 11/1448 Management of the data involved in backup or backup restore
• CPC Class Codes: G06F 11/1453 using de-duplication of the data
• CPC Class Codes: G06F 11/1469 Backup restoration techniques
• CPC Class Codes: G06F 2201/84 Using snapshots, i.e. a logical point-in-time copy of the data
• CPC Class Codes: G06F 3/0619 in relation to data integrity, e.g. data losses, bit errors
• CPC Class Codes: G06F 3/0641 De-duplication techniques
• CPC Class Codes: G06F 3/065 Replication mechanisms
• CPC Class Codes: G06F 3/0665 at area level, e.g. provisioning of virtual or logical volumes
• CPC Class Codes: G06F 3/067 Distributed or networked storage systems, e.g. storage area networks [SAN], network attached storage [NAS]

Abstract

The systems and methods herein permit storage systems to correctly perform data recovery, such as direct access recovery, of Network Data Management Protocol (“NDMP”) backup data that was modified prior to being stored in secondary storage media, such as tape. For example, as described in greater detail herein, the systems and methods may permit NDMP backup data to be encrypted, compressed, deduplicated, and/or otherwise modified prior to storage. The systems and methods herein also permit a user to perform a precautionary snapshot of the current state of data (e.g., primary data) prior to reverting data to a previous state using point-in-time data.

Claims

1. A method of handling a Network Data Management Protocol (“

NDMP”

) backup or copy operation, the method comprising;

receiving an original NDMP backup data stream from a client;

modifying the received original NDMP backup data stream by performing one or more of the following modification procedures upon the original NDMP backup data stream;

deduplication, encryption, and compression,

wherein the one or more modification procedures creates a modified version of the NDMP backup data stream;

storing the modified version of the NDMP backup data stream in stored chunks,

wherein each chunk is addressable by a physical offset and a physical length,

wherein each chunk represents a modified version of a contiguous subset of the original NDMP backup data stream, and,

wherein the client associates a logical offset and a logical length with the contiguous subset of the original NDMP backup data stream that is represented by each chunk; and

,

for each stored chunk, associating the stored chunk with;

the physical offset and physical length that permits addressing of the chunk, and,

the logical offset and logical length that the client associates with the contiguous subset of the original NDMP backup data stream that is represented by the chunk.

2. The method of claim 1 further comprising:

receiving a request for a certain subset of the original NDMP backup data stream,

wherein the request includes a logical offset and a logical length;

using the received logical offset and logical length to;

identify a stored chunk that comprises a modified version of at least a portion of the requested subset of the original NDMP backup data stream, and

determine a physical offset and a physical length that permits addressing of the identified chunk;

reading at least a portion of the identified chunk using the determined physical offset and physical length;

converting the portion of the identified chunk by reversing each of the modification procedures that was previously performed upon the original NDMP backup data stream in order to create a converted version of the portion of the identified chunk; and

,

sending data from the converted version of the portion of the identified chunk that is at least a portion of the requested subset of the original NDMP backup data stream.

3. The method of claim 2, further comprising:

reading another portion of the identified chunk;

converting the other portion of the identified chunk by reversing each of the modification procedures that was previously performed upon the original NDMP backup data stream to create a converted version of the other portion of the identified chunk;

buffering data from the converted version of the other portion of the identified chunk, wherein the buffered data does not form a portion of the requested subset of the original NDMP backup data stream; and

,

responding to another request for a different subset of the original NDMP backup data stream with at least some of the buffered data.

4. The method of claim 2, further comprising:

reading at least a portion of another chunk that represents a modified version of a contiguous subset of the original NDMP backup data stream that is adjacent to at least a portion of the requested subset of the original NDMP backup data stream;

converting the portion of the other chunk by reversing each of the modification procedures that was previously performed upon the original NDMP backup data stream to create a converted version of the portion of the other chunk;

buffering data from the converted version of the portion of the other chunk, wherein the buffered data does not form a portion of the requested subset of the original NDMP backup data stream; and

,

responding to another request for a different subset of the original NDMP backup data stream with at least some of the buffered data.

5. The method of claim 1, wherein modifying the received original NDMP backup data stream further comprises adding metadata to the data stream.

6. The method of claim 1, wherein a storage policy specifies a configuration of the backup or copy operation.

7. The method of claim 1, wherein associating a stored chunk with a physical offset, physical length, logical offset, and logical length comprises associating a chunk identifier with the physical offset, physical length, logical offset, and logical length in a chunk mapping table.

8. The method of claim 1,

wherein modifying the received original NDMP backup data stream comprises performing deduplication;

and

wherein at least one chunk corresponds to a deduplication data structure that is created by the performance of deduplication.

9. The method of claim 1,

wherein modifying the received original NDMP backup data stream comprises performing deduplication;

and

wherein at least one chunk corresponds to a logical subdivision of a deduplication data structure that is created by the performance of deduplication.

10. The method of claim 1, wherein a storage policy specifies an approximate size of the stored chunks.

11. The method of claim 1, wherein the size of stored chunks is configurable to tune performance of restore operations.

12. The method of claim 1, further comprising:

determining that one or more stored chunks are being moved to a new physical location during a storage operation; and

,

for each of the one or more moved chunks, associating the chunk and its associated logical offset and logical length with a new physical offset and new physical length that permits addressing of the chunk at its new physical location.

13. A system for handling a Network Data Management Protocol (“

NDMP”

) backup or copy operation, the system comprising;

a processor; and

,

a secondary storage computing device, coupled to the processor, configured to;

receive an original NDMP backup data stream from a client;

modify the received original NDMP backup data stream by performing one or more of the following modification procedures upon the original NDMP backup data stream;

deduplication, encryption, and compression,

wherein the one or more modification procedures create a modified version of the NDMP backup data stream;

store the modified version of the NDMP backup data stream in stored chunks,

wherein each chunk is addressable by a physical offset and a physical length,

wherein each chunk represents a modified version of a subset of the original NDMP backup data stream, and,

wherein the client associates a logical offset and a logical length with the subset of the original NDMP backup data stream that is represented by each chunk; and

,

for each stored chunk, associate the stored chunk with;

the physical offset and physical length that permits addressing of the chunk, and,

the logical offset and logical length that the client associates with the subset of the original NDMP backup data stream that is represented by the chunk.

14. The system of claim 13 wherein the secondary storage computing device is further configured to:

receive a request for a certain subset of the original NDMP backup data stream, wherein the request includes a logical offset and a logical length;

use the received logical offset and logical length to;

identify a stored chunk that comprises a modified version of at least a portion of the requested subset of the original NDMP backup data stream, and

determine a physical offset and a physical length that permits addressing of the identified chunk;

read at least a portion of the identified chunk using the determined physical offset and physical length;

convert the portion of the identified chunk by reversing each of the modification procedures that was previously performed upon the original NDMP backup data stream in order to create a converted version of the portion of the identified chunk; and

,

send data from the converted version of the portion of the identified chunk that is at least a portion of the requested subset of the original NDMP backup data stream.

15. The system of claim 14, wherein the secondary storage computing device is further configured to:

read another portion of the identified chunk;

convert the other portion of the identified chunk by reversing each of the modification procedures that was previously performed upon the original NDMP backup data stream to create a converted version of the other portion of the identified chunk;

buffer data from the converted version of the other portion of the identified chunk, wherein the buffered data does not form a portion of the requested subset of the original NDMP backup data stream; and

,

respond to another request for a different subset of the original NDMP backup data stream with at least some of the buffered data.

16. The system of claim 14, wherein the secondary storage computing device is further configured to:

read at least a portion of another chunk that represents a modified version of a subset of the original NDMP backup data stream that is adjacent to at least a portion of the requested subset of the original NDMP backup data stream;

convert the portion of the other chunk by reversing each of the modification procedures that was previously performed upon the original NDMP backup data stream to create a converted version of the portion of the other chunk;

buffer data from the converted version of the portion of the other chunk, wherein the buffered data does not form a portion of the requested subset of the original NDMP backup data stream; and

,

respond to another request for a different subset of the original NDMP backup data stream with at least some of the buffered data.

17. The system of claim 13,

wherein the secondary storage computing device modifies the received original NDMP backup data stream by performing deduplication;

and

wherein at least one chunk corresponds to a deduplication data structure that is created by the performance of deduplication.

18. The system of claim 13, wherein a data storage policy specifies an approximate size of the stored chunks.

19. The system of claim 13, wherein the secondary storage computing device is further configured to:

determine that one or more stored chunks are being moved to a new physical location during a storage operation; and

,

for each of the one or more moved chunks, associate the chunk and its associated logical offset and logical length with a new physical offset and new physical length that permits addressing of the chunk at its new physical location.

20. A tangible computer-readable storage medium whose contents cause a data storage system to perform an operation for recovering Network Data Management Protocol (“

NDMP”

) backup data, the operation comprising;

receiving a request for an unmodified version of NDMP data that was modified prior to being stored in secondary storage media, the request including a logical offset and a logical length; and

,

returning the requested unmodified version of NDMP data using the received logical offset and logical length.

21. The computer-readable storage medium of claim 20, wherein the NDMP data that was modified prior to being stored in secondary storage media was modified by one or more of:

deduplication, encryption, and compression.

22. The computer-readable storage medium of claim 20,

wherein returning the requested unmodified version of NDMP data using the received logical offset and logical length comprises accessing an index using the received logical offset and logical length to identify from the index a physical offset and physical length associated with a physical data storage device, and

wherein the physical offset and physical length permit addressing and accessing a stored chunk of data that represents a modified form of a portion of the requested NDMP data.

23. A data storage system for reverting data to a previous state using point-in-time data, the system comprising:

means for receiving a request from a user to revert data to an earlier state at a previous time using previously obtained point-in-time data;

means for presenting the user with an option to take a snapshot of a current state of the data;

means for determining whether the user has requested that a snapshot of the current state of the data be taken;

means for taking a snapshot of the current state of the data, when the user has requested that a snapshot of the current state of the data be taken; and

,

means for reverting the data using the previously obtained point-in-time data.

24. The system of claim 23, wherein the means for presenting the user with the option to take a snapshot of the current state of the data includes means for presenting a displayable dialog box that provides the user with:

an option to take a snapshot of the current state of the data, and,

an option to always take a precautionary snapshot before reverting data.

25. A tangible computer-readable storage medium whose contents cause a data storage system to perform an operation for reverting a set of data, the operation comprising:

performing a precautionary snapshot of a current state of a set of data, and,

reverting the set of data to a previous state using point-in-time data, wherein the precautionary snapshot is performed prior to reverting the set of data.

26. The tangible computer-readable storage medium of claim 25, wherein the operation further comprises:

receiving a user'"'"'s request to revert the set of data to a previous state using the point-in-time data;

in response to the request, automatically providing a user interface display that presents the user with the option to perform the precautionary snapshot, and,

receiving the user'"'"'s selection of the option to perform the precautionary snapshot via the user interface display.