Method and apparatus for performing bulk file system attribute retrieval

• US 20070179934A1
• Filed: 01/27/2006
• Published: 08/02/2007
• Est. Priority Date: 01/27/2006
• Status: Active Grant

• Current Assignee: Emc IP Holding Company LLC (Dell Technologies Inc.)
• Original Assignee: EMC Corporation (Dell Technologies Inc.)
• Inventors: Zheng, Jiannan, Jiang, Xiaoye, Fridella, Stephen, Zimran, Eyal, Gupta, Uday, Stacey, Christopher, Chuba, Christian, Basov, Ivan
• Granted Patent: US 8,560,569 B2
• Time in Patent Office: Days
• US Class Current: 1/1
• CPC Class Codes: G06F 16/2272 Management thereof
• CPC Class Codes: G06F 16/244 Grouping and aggregation
• CPC Class Codes: G06F 16/24556 Aggregation; Duplicate elimination

Abstract

Accordingly a method and interface allows an attribute data base used by an Information Manager to be quickly populated and accurately maintained. A single Bulk Attribute Retrieval Request triggers the primary storage device to collect object attribute information. The method allows for selective collection of objects and attributes by providing filters and attribute lists in the Requests. The Request may be used to provide an incremental scan with appropriate time stamp filtering. In addition, the size of the results can be controlled by the IM by eliminating attributes that are not of interest to the IM. The Request is advantageously issued over a FileMover interface, which is an HTTP connection, and encoded in XML, allowing the IM to easily customize the Request as desired.

Claims

1. A method of collecting file system object attributes in response to a Bulk Attribute Retrieval (BAR) request includes the step of:

decoding the BAR request to identify a file system tree;

identifying file system objects associated with the file system tree and retrieving attributes of the identified file objects; and

selectively storing the retrieved attributes of each identified object in a result file.

2. The method of claim 1, wherein the retrieved attributes are selected from a group including all attributes of each identified object.

3. The method of claim 2, wherein the group of all attributes includes attributes associated with different network protocols.

4. The method of claim 3, wherein the different network protocols include Network Attached Storage (NAS) protocols.

5. The method of claim 1, wherein the BAR request identifies a filtering attribute and a filtering attribute condition for use in filtering identified objects, and wherein the step of selectively storing discards identified objects having values for the filtering attribute that do not satisfy the filtering attribute condition.

6. The method according to claim 5, wherein the filtering attribute is a timestamp.

7. The method according to claim 6, wherein the timestamp is selected from a group including a modify time stamp, and access time stamp and a change time stamp.

8. The method according to claim 6, further including the step of providing an incremental scan of the file system by:

retrieving a checkpoint associated with the time stamp;

identifying inode blocks in the file system that have been modified since the checkpoint;

and wherein the step of identifying objects examines only objects associated with changed inode blocks.

9. The method according to claim 5, wherein the filtering attribute is one of an offline and online status.

10. The method according to claim 5, wherein the filtering attribute is a file size.

11. The method according to claim 5, wherein the filtering attribute is a file type.

12. The method of claim 1, wherein the BAR request includes an attribute list, and wherein the step of selectively storing the retrieved attributes discards attribute types that are not included on the attribute list.

13. The method of claim 12, wherein the attribute list includes at least one attribute selected from a group of modification time, access control list, off-line status, permission bits, file type, WORM status, access time, change time, owner, group, DOS read-only bit, DOS archive bit, link count, file size, directory size, DOS name, Unix name, Win32 name, or extended attributes.

14. A method of collecting file system object attributes includes the step of:

encoding a Bulk Attribute Retrieval (BAR) request including a file system root and an output file name;

forwarding the BAR request to a storage system to retrieve attributes associated with objects in the file system;

receiving a response indicating that a collection of attributes has completed; and

retrieving an output file having the output file name from the storage system.

15. The method of claim 14, wherein the BAR request includes a filter attribute and a filter attribute condition to be applied against a corresponding attribute of each object in the file system to determine whether the attributes of the object are returned in the output file.

16. The method according to claim 15, wherein the filtering attribute is a timestamp.

17. The method according to claim 16, wherein the timestamp is selected from a group including a modify time stamp, and access time stamp and a change time stamp.

18. The method according to claim 15, further including the step of requesting an incremental scan of the file system by forwarding the time stamp associated with a last scan in the BAR request.

19. The method according to claim 15, wherein the filtering attribute is an offline status.

20. The method according to claim 15, wherein the filtering attribute is a file size.

21. The method according to claim 15, wherein the filtering attribute is a file type.

22. The method of claim 14, wherein the BAR request includes an attribute list to limit the types of attributes that are returned in the output file.

23. The method of claim 22, wherein the attribute list includes at least one attribute selected from a group including offline status, permission bits, access control lists, file type, WORM status, access time, change time, owner, group, DOS read-only bit, DOS archive bit, link count, file size, directory size, DOS name, Unix name, Win32 name, or extended attributes.

24. An apparatus for generating a Bulk Attribute Retrieval (BAR) result including attributes associated with file system objects includes:

decode logic for decoding a BAR Request to determine a file system root;

a file system, stored on a computer readable medium, the file system including a plurality of objects, each object having a plurality of attributes;

means for searching the file system to identifying file system objects associated with the file system root and for retrieving attributes of the identified file objects;

a data store; and

means for selectively storing the retrieved attributes of each identified object in a result file in the data store.

25. The apparatus of claim 24, wherein the means for selectively storing includes a filter for selectively discarding retrieved attributes in response to at least one field of the BAR Request.

26. The apparatus of claim 25, wherein the at least one field includes a filter attribute field, a filter attribute value field, and a filter attribute comparison field.

27. The apparatus of claim 25, wherein the at least one field includes an attribute list field.

28. The apparatus of claim 26, further comprising:

checkpoint logic for obtaining periodic snapshots of file system contents;

comparison logic for identifying blocks that have been modified between checkpoints; and

wherein the means for searching the file system examines only those objects having identified modified blocks.

29. The apparatus of claim 24, further comprising an HTTP interface, and wherein the BAR Request is received at the HTTP interface from an HTTP connection with an Information Manager.

30. The apparatus of claim 24, wherein the apparatus further includes a network interface, and wherein the output file is forwarded to an Information Manager over the network interface.

31. The apparatus of claim 30, wherein the network interface operates according to the Hyper-Text Transfer Protocol (HTTP), and wherein the output file is streamed to a host device over an HTTP connection on the network interface.

32. The apparatus of claim 24, wherein the network interface operates according to a Network Attached Storage (NAS) Protocol.

33. An application programming interface, stored in a computer readable medium of a file server, includes:

program code operable when executed in response to a Bulk Attribute Retrieval (BAR) request to;

decode the BAR request to identify a file system root;

identify file system objects associated with the file system tree and retrieve attributes of the identified file objects; and

selectively store the retrieved attributes of each identified object in a result file.

34. A file server comprising a computer readable medium having program code stored thereon, the program code including:

a Bulk Attribute Retrieval (BAR) instruction, the BAR instruction comprising a file system path name and an output file name, the BAR instruction operable, when executed, to cause the file server to selectively collect attributes of objects in the file system associated with the file system path name for placement into an output file matching the output file name.

35. The file server of claim 34, wherein the BAR instruction includes one or more filters, and wherein the instruction is operable when executed to limit the attributes that are provided in the output file in accordance with the filters.

36. The file server of claim 34, wherein the filters include attribute value filters.

37. The file server of claim 34, wherein the filters include attribute type filters.