BLOCK LEVEL BACKUP AND RESTORE

• US 20130080391A1
• Filed: 05/24/2012
• Published: 03/28/2013
• Est. Priority Date: 09/23/2011
• Status: Active Grant

• Current Assignee: International Business Machines Corporation
• Original Assignee: International Business Machines Corporation
• Inventors: Raichstein, Eran, Sternberg, Michael, Van Hise, David G., Wolloch, Uri
• Granted Patent: US 8,812,446 B2
• Time in Patent Office: Days
• US Class Current: 707/645
• 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 method for block level backup, comprising:

creating, using a processor of a backup server, a full image level backup of a file system from production storage at a production server to random access storage at the backup server;

performing file enumeration on a mounted image created from the full image that exposes a block level representation of the file system for files;

monitoring block level read operations that reference meta-data blocks while the files are being enumerated;

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

identifying 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.

2. The method of claim 1, further comprising:

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 method of claim 2, further comprising:

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

4. The method of claim 1, further comprising:

receiving a request to restore a file from the backup image;

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 accesses of the read operations in the file level format; and

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

5. The method of claim 1, further comprising:

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

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

6. The method of claim 1, further comprising:

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

creating a new, synthetic full image for each of the at least one full image or incremental image from relevant data blocks and meta-data blocks.

7. The method of claim 1, wherein the block level representation of the file system is presented to an operating system at the production server.

8-20. -20. (canceled)