DISTRIBUTED, UNIFIED FILE SYSTEM OPERATIONS

• US 20120254140A1
• Filed: 03/31/2011
• Published: 10/04/2012
• Est. Priority Date: 03/31/2011
• Status: Active Grant

• Current Assignee: Micro Focus Software, Inc. (Open Text Corporation)
• Original Assignee: Novell Incorporated (Open Text Corporation)
• Inventors: Srinivasaraghavan, Haripriya, Madhavan, Vijai Babu
• Granted Patent: US 9,037,618 B2
• Time in Patent Office: Days
• US Class Current: 707/705
• CPC Class Codes: G06F 11/1435 using file system or storage system metadata
• CPC Class Codes: G06F 16/1844 Management specifically adapted to replicated file systems
• CPC Class Codes: G06F 16/9014 hash tables

Abstract

Apparatus, systems, and methods may operate to receive a request to access a file from a client node at one of a plurality of lookup nodes, the lookup nodes storing portions of a distributed table having lookup information associated with the file. The distributed table, which may comprise a distributed hash table, includes replicated references to virtualized and non-virtualized file elements of varied granularity in a unified file system. Additional activity may comprise forwarding the request to another one of the lookup nodes until the lookup information is located, or chaining the request to one of the plurality of lookup nodes and implementing activity that has been requested. Additional apparatus, systems, and methods are disclosed.

Claims

1. A system, comprising:

a plurality of lookup nodes to store portions of a distributed table having lookup information associated with a file, wherein the distributed table includes replicated references to virtualized and non-virtualized file elements of varied granularity in a unified file system; and

a processor within one of the lookup nodes to receive a request from a client node to access the file, and to forward the request to another one of the lookup nodes until the lookup information is located, or to chain the request to one of the plurality of lookup nodes so that activity that has been requested can be directly implemented.

2. The apparatus of claim 1, further comprising:

a user input device operating as the client node.

3. The apparatus of claim 1, wherein the lookup nodes comprise a combination of file servers and file meta-data servers.

4. The apparatus of claim 1, wherein the client node is housed together with at least one of the lookup nodes.

5. The apparatus of claim 1, further comprising:

a memory to store policies that direct a lookup path through the lookup nodes when the lookup information is not located within the one of the lookup nodes that includes the processor.

6. The apparatus of claim 1, further comprising:

a hashing module to generate a hash of a filename associated with the file or a path in a hierarchy associated with the file.

7. A processor-implemented method to execute on one or more processors that perform the method, comprising:

receiving a request to access a file from a client node at one of a plurality of lookup nodes, the lookup nodes storing portions of a distributed table having lookup information associated with the file, wherein the distributed table includes replicated references to virtualized and non-virtualized file elements of varied granularity in a unified file system; and

forwarding the request to another one of the lookup nodes until the lookup information is located, or chaining the request to one of the plurality of lookup nodes and implementing activity that has been requested.

8. The method of claim 7, further comprising:

transmitting the lookup information to the client node, wherein the lookup information permits the client node to access the file.

9. The method of claim 7, further comprising:

accessing a policy to determine a next lookup node to which the request will be forwarded.

10. The method of claim 9, wherein a reference in the table comprises a location of the lookup information, or a location of a subsequent one of the lookup nodes.

11. The method of claim 7, further comprising:

redirecting the client node to a second server node in the file system when the first server node, referenced by the lookup information, determines that the lookup information refers to one of the virtualized file elements.

12. The method of claim 7, wherein at least one of the replicated references to one of the virtualized file elements comprises one of a symbolic link or an extended attribute.

13. The method of claim 7, wherein a first subset of the replicated references are formatted according to a first protocol, and wherein a second subset of the replicated references are formatted according to a second protocol different from the first protocol.

14. A processor-implemented method to execute on one or more processors that perform the method, comprising:

receiving a request to access a file from a client node at one of a plurality of lookup nodes, the lookup nodes storing portions of a distributed hash table having lookup information associated with the file, wherein the distributed table includes replicated references to virtualized and non-virtualized file elements of varied granularity in a unified file system; and

forwarding the request to another one of the lookup nodes until the lookup information is located, or chaining the request to one of the plurality of lookup nodes to implement activity associated with the file, as indicated by the request.

15. The method of claim 14, wherein the unified file system comprises a unified single logical namespace to virtualize distributed volumes and/or individual file locations.

16. The method of claim 14, further comprising:

selecting one reference from the replicated references based on a policy.

17. The method of claim 14, further comprising:

locating the lookup information by matching a key in the hash table to a hash of a name associated with the file.

18. The method of claim 14, further comprising:

after the lookup information is located, performing activity associated with the request, on the file, by one of the lookup nodes when it is determined that the file comprises a data element directly accessible by the one of the lookup nodes.

19. The method of claim 14, further comprising:

partitioning the hash table among the plurality of lookup nodes so that some entries in the hash table in each one of the lookup nodes overlap entries in the hash table in at least one of the other lookup nodes.

20. The method of claim 14, further comprising:

adding an additional lookup node to the plurality of lookup nodes by selecting a portion of the hash table included in the additional lookup node and distributing the portion to at least one other one of the lookup nodes.