Block level backup and restore

• US 8,843,451 B2
• Filed: 09/23/2011
• Issued: 09/23/2014
• Est. Priority Date: 09/23/2011
• Status: Expired due to Fees

• Current Assignee: International Business Machines SA (International Business Machines Corporation)
• Original Assignee: International Business Machines Corporation
• Inventors: Sternberg, Michael, Van Hise, David G., Wolloch, Uri, Raichstein, Eran
• Primary Examiner(s): Mofiz, Apu
• Assistant Examiner(s): Jacob, Ajith
• Application Number:
  US13/243,789
• Publication Number:
  US 20130080390A1
• Time in Patent Office: 1,096 Days
• Field of Search: 707/653
• US Class Current: 707/653
• CPC Class Codes: G06F 11/1448 Management of the data involved in backup or backup restore
• CPC Class Codes: G06F 11/1451 by selection of backup contents
• CPC Class Codes: G06F 11/1458 Management of the backup or restore process
• CPC Class Codes: G06F 11/1469 Backup restoration techniques
• CPC Class Codes: G06F 16/10 File systems; File servers
• CPC Class Codes: G06F 16/1724 Details of de-fragmentation performed by the file system saving storage space on storage systems G06F3/0608; management of blocks in storage devices G06F3/064
• 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

Abstract

For block level backup, a full image level backup is created of a file system from production storage at a production server to random access storage at a backup server. A mounted image is created from the full image that exposes a block level representation of the file system of the production server for read operations in a file level format. File enumeration is performed on the mounted image for files. Block level read operations are monitored while the files are being enumerated. During monitoring, blocks that are read for the read operations are marked as meta-data blocks. Blocks that are not marked as meta-data blocks are identified as data blocks. The data blocks are migrated to sequential storage, while leaving the meta-data blocks on the random access storage, wherein the data blocks form a backup image.

Claims

1. A computer program product for block level backup, the computer program product comprising:

a non-transitory computer readable storage medium having computer readable program code embodied therewith, wherein the computer readable program code, when executed by a processor of a backup server, is configured to perform;

while performing file enumeration on a mounted image created from a full image that exposes a block level representation of a file system for files for access by an operating system of a production server, marking blocks for read operations that reference meta-data blocks as the meta-data blocks, wherein the blocks that are not marked as the meta-data blocks are data blocks;

in response to the file enumeration completing, migrating the data blocks to sequential storage, while leaving the meta-data blocks on random access storage, wherein the data blocks form a backup image; and

in response to receiving a request to restore a file from the backup image for the production server,

retrieving relevant meta-data blocks from the random access storage that indicate where the data blocks for the file are stored in the sequential storage;

creating a new, mounted image from the relevant meta-data blocks that exposes a block level representation of the file system for access by the operating system;

performing non-data related operations against the new, mounted image; and

restoring the file by reading the data blocks for that file from the sequential storage to production storage at the production server.

2. The computer program product of claim 1, wherein the computer readable program code, when executed by the processor of the backup server, is configured to perform:

monitoring file changes on the production storage;

performing an incremental image level backup to the random access storage;

creating a new, mounted image from the incremental image that exposes a block level representation of the file system for accesses of the read operations in the file level format;

performing file enumeration on the new, mounted image for files that have changed;

monitoring block level read operations while the files that have changed are being enumerated;

during monitoring, marking blocks that are read for the read operations as meta-data blocks;

identifying the blocks that are not marked as meta-data blocks as data blocks; and

migrating the data blocks to sequential storage, while leaving the meta-data blocks on the random access storage, wherein the data blocks form a backup image.

3. The computer program product of claim 2, wherein the computer readable program code, when executed by the processor of the backup server, is configured to perform:

receiving a list of the files that have changed from a file level filter.

4. The computer program product of claim 1, wherein the computer readable program code, when executed by the processor of the backup server, is configured to perform:

identifying at least one of a full image and an incremental image that is to be retained;

deleting the data blocks and the meta-data blocks that relate to the at least one of the full image and the incremental image; and

re-creating the at least one of the full image and the incremental image for which the data blocks and the meta-data blocks were deleted.

5. The computer program product of claim 1, wherein the computer readable program code, when executed by the processor of the backup server, is configured to perform:

creating a new, synthetic full image for at least one of a full image and an incremental image that is to be retained from relevant data blocks and meta-data blocks.

6. The computer program product of claim 1, wherein the block level representation of the file system is presented to the operating system at the production server.

7. A backup server for block level backup, comprising:

a processor;

a storage device coupled to the processor;

a random access storage device coupled to the backup server;

a sequential storage device coupled to the backup server;

wherein the storage device has stored thereon a program, and

wherein the processor is configured to execute instructions of the program to perform operations, wherein the operations comprise;

while performing file enumeration on a mounted image created from a full image that exposes a block level representation of a file system, marking blocks for read operations that reference meta-data blocks as the meta-data blocks, wherein the blocks that are not marked as the meta-data blocks are data blocks;

in response to the file enumeration completing, migrating the data blocks to the sequential storage device, while leaving the meta-data blocks on random access storage device, wherein the data blocks form a backup image; and

in response to receiving a request to restore a file from the backup image for the production server,

retrieving relevant meta-data blocks from the random access storage that indicate where the data blocks for the file are stored in the sequential storage;

creating a new, mounted image from the relevant meta-data blocks that exposes a block level representation of the file system for access by the operating system;

performing non-data related operations against the new, mounted image; and

restoring the file by reading the data blocks for that file from the sequential storage to production storage at the production server.

8. The backup server of claim 7, wherein the operations further comprise:

monitoring file changes on the production storage device;

performing an incremental image level backup to the random access storage device;

creating a new, mounted image from the incremental image that exposes a block level representation of the file system for accesses of the read operations in the file level format;

performing file enumeration on the new, mounted image for files that have changed;

monitoring block level read operations while the files that have changed are being enumerated;

during monitoring, marking blocks that are read for the read operations as meta-data blocks;

identifying the blocks that are not marked as meta-data blocks as data blocks; and

migrating the data blocks to sequential storage device, while leaving the meta-data blocks

on the random access storage device, wherein the data blocks form a backup image.

9. The backup server of claim 8, wherein the operations further comprise:

receiving a list of the files that have changed from a file level filter.

10. The backup server of claim 7, wherein the operations further comprise:

identifying at least one of a full image and an incremental image that is to be retained;

deleting the data blocks and the meta-data blocks that relate to the at least one of the full image and the incremental image; and

re-creating the at least one of the full image and the incremental image for which the data blocks and the meta-data blocks were deleted.

11. The backup server of claim 7, wherein the operations further comprise:

creating a new, synthetic full image for at least one of a full image and an incremental image that is to be retained from relevant data blocks and meta-data blocks.

12. The backup server of claim 7, wherein the block level representation of the file system is presented to the operating system at the production server.