File block addressing for backups

Patent metadata

Field	Value
Publication number	US-9542397-B1
Application number	US-201313803134-A
Country	US
Kind code	B1
Filing date	Mar 14, 2013
Priority date	Mar 14, 2013
Publication date	Jan 10, 2017
Grant date	Jan 10, 2017

Abstract

Systems and methods for backing up data and for restoring at least sub-sets of the backed up data or for restoring sub-sets of data from a single file. An offset map is generated when backing up data. The offset map identifies at least starting locations of files and data records in the backup. A request for specific data is accommodated by identified the start locations of the specific data and then extracting the requested data from the backup. The requested data can then be restored independently of the entire backup.

First claim

What is claimed is:

1. A method for managing data in a computing system, the method comprising:
initiating a backup of data stored in storage of the computing system, wherein the data includes a plurality of files;
generating a backup stream that includes the backup of the data by encapsulating the plurality of files into a series of records wherein each record includes one or more blocks, wherein the backup is stored in a storage associated with a backup server;
creating an offset map for the data in the backup, wherein the offset map identifies files included in the backup and starting locations of the records included in each of the files in the backup;
storing the offset map in association with the backup; and
configuring a destination suitable for restoring the data in the backup;
issuing a request for at least a sub-set of a file to an application from a user interface associated with a backup client, wherein the application makes a request for the sub-set of the file from the destination;
intercepting the request from the application, by a filter driver, for the sub-set of the file, wherein the filter driver communicates the intercepted request to a backup client that identifies identify the records in the backup corresponding to the request using the offset map associated with the backup;
restoring at least the sub-set of the file identified in the intercepted request from the backup to the destination and providing at least the sub-set of the file in a response to the intercepted request, wherein the sub-set of the file is located using the offset map.

2. The method of claim 1 , wherein creating an offset map for the data further includes populating the offset map with one or more of backup stream offsets, file block sizes, and file block addresses.

3. The method of claim 2 , wherein populating the offset map includes populating the offset map such that a backup stream offset is included for each record in each file in the backup stream, wherein the files are arranged sequentially in the backup stream.

4. The method of claim 3 , further comprising storing the offset map in the sequential backup stream.

5. The method of claim 3 , further comprising storing the offset map separately from the sequential backup stream.

6. The method of claim 1 , wherein the offset is created during the generation of the backup or after the generation of the backup.

7. The method of claim 1 , wherein restoring only a selected sub-set of a file from the backup comprises using the offset map to identify start locations of the data records corresponding to the selected file sub-set, wherein the offset map comprises a file record that corresponds to the file whose sub-set is restored, the file record including a corresponding file offset map having a plurality of entries that each include a file block address, a file block size, and a backup stream offset, wherein the backup stream offsets each identify a location of a particular respective data record in the backed up file.

8. The method as recited in claim 1 , wherein the file sub-set includes non-contiguous data blocks.

9. The method as recited in claim 1 , wherein the backup includes multiple files that are related to each other, one of which is the file from which the file sub-set is taken, and wherein the intercepted request identifies an additional file sub-set that is associated with another of the related files.

10. The method as recited in claim 1 , wherein the file sub-set is restored without necessitating restoration of the entire file from which the file sub-set is taken.

11. The method as recited in claim 1 , wherein the file sub-set is associated with a sparsely mounted database or virtual hard disk.

12. The method as recited in claim 1 , wherein the intercepted request identifies multiple different starting locations within the file.

13. The method as recited in claim 1 , wherein the offset map is created by at least one of a backup client and a backup server.

14. The method as recited in claim 1 , wherein during generation of the backup, information concerning a relative location of each of the one or more files and each of the one or more records of each file in the sequential backup stream is obtained and incorporated into the offset map.

15. The method as recited in claim 1 , wherein the restored file sub-set is associated with a mail application.

16. The method as recited in claim 1 , further comprising restoring a selected sub-set of another file that is different from the file.

17. The method as recited in claim 1 , wherein generating the backup of the data using a streaming format comprises generating the backup of the data using a sequential streaming format.

18. A non-transitory storage medium having stored therein computer-executable instructions which, when executed by one or more hardware processors, manage data in a computing system, wherein management of data comprises:
initiating a backup of data stored in storage of the computing system, wherein the data includes a plurality of files;
generating a backup stream that includes the backup of the data by encapsulating the plurality of files into a series of records using a streaming format, wherein each record includes one or more blocks, wherein the backup is stored in a storage associated with a backup server;
creating an offset map for the data in the backup, wherein the offset map identifies files included in the backup and starting locations of the records included in the backup;
storing the offset map in association with the backup;
configuring a destination suitable for restoring the data in the backup;
issuing a request for at least a sub-set of a file to an application from a user interface associated with a backup client, wherein the application makes a request for the sub-set of the file from the destination;
intercepting the request from the application, by a filter driver, for the sub-set of the file, wherein the filter driver communicates the intercepted request to the backup client that identifies the records in the backup corresponding to the request using the offset map associated with the backup;
restoring at least the sub-set of the file identified in the intercepted request from the backup to the destination and providing at least the sub-set of the file in a response to the intercepted request.

19. A physical device, wherein the physical device comprises:
one or more hardware processors; and
the non-transitory storage medium as recited in claim 18 .

Assignees

• Emc Corp
• Emc Ip Holding Co Llc

Inventors

• Graham Debra H
• Buchman Matthew D

Classifications

• G06F11/14

  Error detection or correction of the data by redundancy in operations (error detection or correction of the data by redundancy in hardware G06F11/16) · CPC title

• G06F11/00

  Error detection; Error correction; Monitoring (error detection, correction or monitoring in information storage based on relative movement between record carrier and transducer G11B20/18; monitoring, i.e. supervising the progress of recording or reproducing G11B27/36; in static stores G11C29/00) · CPC title

• G06F3/0643

  Management of files · CPC title

• G06F3/067

  Distributed or networked storage systems, e.g. storage area networks [SAN], network attached storage [NAS] · CPC title

• G06F16/2282 Primary

  Tablespace storage structures; Management thereof · CPC title