System and method for managing a plurality of snapshots

• US 7,475,098 B2
• Filed: 03/19/2002
• Issued: 01/06/2009
• Est. Priority Date: 03/19/2002
• Status: Active Grant

• Current Assignee: Network Appliance Incorporated (NetApp, Inc.)
• Original Assignee: Network Appliance Incorporated (NetApp, Inc.)
• Inventors: Manley, Stephen L., Skardal, Harald I., Patterson, Hugo
• Primary Examiner(s): Wong; Don
• Assistant Examiner(s): Nguyen; Merilyn P
• Application Number:
  US10/101,901
• Publication Number:
  US 20030182301A1
• Time in Patent Office: 2,485 Days
• Field of Search: 707/1, 707/102, 707/200, 707/203, 707/204, 707/201, 711/136, 711/162, 711/302, 714/5, 714/20
• US Class Current: 1/1
• CPC Class Codes: G06F 11/1456 Hardware arrangements for backup
• 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 11/1464 for networked environments
• CPC Class Codes: G06F 11/1469 Backup restoration techniques
• CPC Class Codes: G06F 11/1471 involving logging of persistent data for recovery
• CPC Class Codes: G06F 11/2064 while ensuring consistency
• CPC Class Codes: G06F 16/00 Information retrieval; Database structures therefor; File system structures therefor
• CPC Class Codes: G06F 2201/84 Using snapshots, i.e. a logical point-in-time copy of the data
• CPC Class Codes: Y10S 707/99953 Recoverability
• CPC Class Codes: Y10S 707/99955 Archiving or backup

Abstract

A system and method for managing a plurality of snapshots as provided. A set of metadata describing a file system is contained within the file system so that a snapshot of the file system includes the associated metadata. Backup client file systems are restored to a backup server using conventional dump and restore techniques. The backup server then utilizes a user-defined snapshot management schedule to manage the set of backups associated with the backup server. Such management of snapshots can include deletion of snapshots based upon a variety of parameters including the time stamp.

Claims

1. In a network including a backup client in communication with a backup server, a method for storing data comprising:

implementing a conventional dump stream by a first client;

accepting the dump stream by a second client;

maintaining by the second client, in response to the dump stream, a complete file system of the first client;

maintaining by a backup server a backup of the second client;

creating a snapshot of the backup of the second client by the backup server, wherein the snapshot is a copy of a root inode of the file system;

requesting, by the first client, a restoration of a file;

restoring from the backup server to the second client a single file, without restoring all files of the file system, from the snapshot; and

using the file system structures to provide the restoration of the file.

2. The method according to claim 1, further comprising:

managing the snapshot and a plurality of other snapshots according to a user-defined schedule.

3. The method of claim 1, further comprises:

creating a metadata file in the file system;

storing file system information in the metadata file; and

generating a snapshot of the file system, the snapshot including the metadata file, to make a self-describing snapshot.

4. The method of claim 3 further comprising:

associating state information with the metadata file.

5. The method of claim 4 wherein the state information identifies the file system as being in a stable state.

6. The method of claim 4 wherein the state information identifies the file system as being in a transitioning state.

7. A system to store data in a network including a backup client in communication with a backup server, comprising:

a first client to implement a dump stream;

a second client to accept the dump stream;

the second client to maintain a complete file system of the first client in response to the dump stream;

a backup server to maintain a backup of the second client;

a snapshot of the backup of the second client created by the backup server, wherein the snapshot is a copy of a root inode of the file system;

the first client configured to request a restoration of a file;

the second client to restore from the backup server a single file, without restoring all files of the file system, from the snapshot; and

the file system structures used to restore the file.

8. The system of claim 7, further comprising:

to create a metadata file in the file system;

to store file system information in the metadata file; and

to generate a snapshot of the file system, the snapshot including the metadata file, to make a self-describing snapshot.

9. The system of claim 8, further comprising:

file system information that includes state information associated with the metadata file.

10. The system of claim 9, wherein the state information identifies the file system as being in a stable state.

11. The system of claim 9, wherein the state information identifies the file system as being in a transitioning state.

12. The system of claim 7, further comprising:

managing the snapshot and a plurality of other snapshots according to a user-defined schedule.

13. In a network including a backup client in communication with a backup server, a method for storing data comprising:

accepting a dump stream of a first client by a second client;

maintaining, in response to the dump stream, by a second client a complete file system of the first client;

maintaining by a backup server a backup of the second client;

creating a snapshot of the backup of the second client by the backup server, wherein the snapshot is a copy of a root inode of the file system;

requesting, by the first client, a restoration of a file;

restoring from the backup server to the second client a single file, without restoring all files of the files system, from the snapshot; and

using the file system structures to provide the restoration of the file.

14. The method of claim 13, further comprises:

creating a metadata file in the file system;

storing file system information in the metadata file; and

generating a snapshot of the file system, the snapshot including the metadata file, to make a self-describing snapshot.

15. The method of claim 14, further comprising:

associating state information with the metadata file.

16. The method of claim 15 wherein the state information identifies the file system as being in a stable state.

17. The method of claim 15 wherein the state information identifies the file system as being in a transitioning state.

18. The method according to claim 13, further comprising:

managing the snapshot and a plurality of other snapshots according to a user-defined schedule.

19. A system to store data by a first server in a network including a backup client in communication with a backup server, comprising:

the backup client to accept a dump stream from the first server;

the backup client to maintain a complete file system of the file server in response to the dump stream;

a backup server to maintain a backup of the backup client;

a snapshot of the backup of the backup client created by the backup server, wherein the snapshot is a copy of a root inode of the file system;

the file server configured to request a restoration of a file;

the backup client to restore from the backup server a single file, without restoring all the files of the file system, from the snapshot; and

the file system structures used to restore the file.

20. The system of claim 19, further comprising:

to create a metadata file in the file system;

to store file system information in the metadata file; and

to generate a snapshot of the file system, the snapshot including the metadata file, to make a self-describing snapshot.

21. The system of claim 20, further comprising:

file system information that includes state information associated with the metadata file.

22. The system of claim 21, wherein the state information identifies the file system as being in a stable state.

23. The system of claim 21, wherein the state information identifies the file system as being in a transitioning state.

24. The system of claim 19, further comprising:

managing the snapshot and a plurality of other snapshots according to a user-defined schedule.